Recognition of group B streptococci in dip-slide cultures of urine. One hundred strains of group B streptococci isolated from human infections were tested for growth on dip-slides available for the culture of urine. All grew on CLED agar, and none grew on MacConkey agar. The colonies were barely or not at all visible to the naked eye after overnight incubation (diameter, around 0.1 mm). The colony size increased eith prolonged incubation, but not if the inoculum density exceeded 10(6)/ml. Differences were found between lots of dip-slides. Poor growth on dip-slides may explain why group B streptococci have received little attention as pathogens of the urinary tract. The dip-slide screening personnel of one laboratory were informed of the experimental findings, and they started the practice of frequent subculture and prolonged incubation. The proportion of group B streptococci in significant bacteriuria increased from 0 to about 2% of positive cultures, whereas there was no conmitant increase of group B streptococci in dip-slides screened in several other laboratories serving as controls.


Clinical laboratory evaluation of automated microbial detection/identification system in analysis of clinical urine specimens. More than 4,000 clinical urine specimens were evaluated with an automated microbial detection/identification system compared to a standarized manual analysis and the routine modalities used in five peer-group laboratories. The comparison indicates that the automated system recognizes the nine groups of significant microorganisms in urinary tract infections in hospitalized patients with the same efficiency as a standarized manual method. The automated system's ability to enumerate the bacterial populations in the original clinical specimen attained a high degree of accuracy.


Application of the Fortner principle to isolation of Campylobacter from stools. A simple biological technique for reducing oxygen tension which does not necessitate the use of conventional anaerobic equipment is described. We successfully applied this method to the isolation of campylobacters from stools.


Modified inoculum for the enteric Minitek system from positive blood cultures. A modified Minitek inoculum procedure for the identification of Enterobacteriaceae from positive blood cultures was shown to be reliable. The method consisted of inoculating the Minitek enteric and nonfermenter broth with blood culture fluid and incubating the inoculum for 4 h before use.


Formalinized Chlamydia trachomatis organisms as antigen in the micro-immunofluorescence test. Chlamydia trachomatis organisms grown in HeLa 229 cell cultures were purified and formalinized for use in the micro-immunofluorescence test. As test antigens, they were stable when stored unfrozen at 4 degrees C for a long period of time without loss of type specificity and sensitivity.


Identification of viridans streptococci on the Minitek Miniaturised Differentiation System. A total of 227 strains of viridans streptococci were simultaneously identified on the Minitek Miniaturised System (BBL) and by a conventional method according to Colman and Williams. The Minitek discs were each overlaid with a drop of sterile liquid paraffin, and the trays were incubated in GaSPak jars (BBL) with CO2 generator envelopes. Identification was possible three to four days earlier than with the conventional method. The results were found to be in agreement with the conventional method. Compared to the identification schemes of Cowan and Steel and of Facklam, the results were also in good agreement. Minor differences were found in the number of positive and negative results in those reactions that are variable in all three schemes.


Cerebral malaria in the United Kingdom.

Cerebral malaria in the United Kingdom. Four fatal cases of cerebral Plasmodium falciparum malaria in English travellers returning from Africa have been seen in the last 13 years. The haemorrhages, accumulations of microglia, and destruction of cerebral white matter around small veins as a result of blockage of cortical capillaries by parasitised red blood corpuscles resemble the effect of fat embolism. Microglia in the lesions is demonstrated by special neuropathological techniques. Attention is drawn to the need for a prompt recognition of malaria since appropriate treatment can be successful.


Pneumocystis carinii pneumonitis: a serological study. Sera from 23 proven or clinically suspected cases of Pneumocystis carinii pneumonitis (PCP) in immunosuppressed patients predominantly with acute lymphoblastic leukaemia, and from 91 normal people, were examined for antibody to P. carinii by indirect immunofluorescence. Low levels of antibody were found in 51 of 91 normal people and elevated or rising titres of antibody in 18 out of 21 cases from whom paired or serial convalescent sera could be obtained.


Anti-cartilage antibody.

Anti-cartilage antibody. Antibody to cartilage has been demonstrated by indirect immunofluorescence on rat trachea in the serum of about 3% of 1126 patients with rheumatoid arthritis. Titres ranged from 1:20 to 1:640. The antibody was not found in 284 patients with primary or secondary osteoarthritis or in 1825 blood donors, nor, with the exception of two weak reactors, in 1314 paraplegic patients. In most cases the antibody appears to be specific for native type II collagen. Using this as an antigen in a haemagglutination test 94% of anti-cartilage sera were positive, whereas among 100 rheumatoid control sera there were only three weak positives. More than 80% of patients with antibody had some erosion of articular cartilage, but there was no correlation with age, sex, duration of disease, nor any recognisable clinical event or change.


Bone aluminium in haemodialysed patients and in rats injected with aluminium chloride: relationship to impaired bone mineralisation. Iliac bone aluminium was determined by neutron activation analysis in 34 patients with chronic renal failure and in eight control subjects. In 17 patients treated by haemodialysis there was a significant increase in the amount of aluminium (mean +/- SE = 152 +/- 30 ppm bone ash). In eight patients treated by haemodialysis and subsequent renal transplantation, bone aluminium was still significantly increased (92 +/- 4.5 ppm bone ash) but was less than in the haemodialysed patients. In some patients aluminium persisted in bone for many years after successful renal transplantation. There was no relationship between hyperparathyroidism and bone aluminium. Although no statistically significant relationship was found between the mineralisation status of bone and bone aluminium, patients dialysed for the longest periods tended to be those with the highest levels of aluminium, osteomalacia, and dialysis encephalopathy. In 20 rats given daily intraperitoneal injections of aluminium chloride for periods of up to three months, there was accumulation of aluminium in bone (163 +/- 9 ppm ash) to levels comparable to those obtained in the dialysis patients, and after about eight weeks osteomalacia developed. The increased bone aluminium and osteomalacia persisted after injections had been stopped for up to 49 days, although endochondral ossification was restored to normal. As a working hypothesis it is suggested that aluminium retained in the bone of the dialysis patients and the experimental animals interferes with normal mineralisation.


Biotypes of Klebsiella pneumoniae (sensu lato) and Enterobacter aerogenes characterised by differential substrate metabolism: application of the technique. A biochemical typing method is described for Klebsiella pneumoniae (sensu lato) and Enterobacter aerogenes. The technique depends on differences in metabolism of five carbon substrates--glycerol, inositol, lactose, glucose, and xylose--at two concentrations. Reproducibility is satisfactory and is monitored by the incorporation of control klebsiellae of known biotype. The method has been used for 12 months in the surveillance of urinary tract colonisation in this hospital. Gut carriage of klebsiellae, implicated by several workers as a source of infection, was common among staff and new admissions. Many biotypes were represented which were sensitive to most antibiotic except ampicillin. Klebsiellae, all multiply resistant, were isolated most frequently from urine specimens in two orthopaedic wards. In a longitudinal study in these wards, a sequential dominance in urinary tract colonisation by two klebsiella biotypes was shown, which suggested the presence of cross infection or an environmental reservoir. Confirmatory evidence was obtained from capsular serotypes and R-factor studies.


Ultrastructural localization of immunoglobulin and fibrin in lichen planus. To demonstrate the exact localization of immunoglobulin and fibrin deposits in skin lesions of lichen planus, we employed the peroxidase-antiperoxidase technique, both light and electron microscopically. IgM is shown to be deposited preferentially in and on the cytoid bodies all over their cut surface in a typical stippled pattern, partly obscuring the characteristic fibrillar substructure. All other structures such as the basal lamina are devoid of IgM deposits. Fibrin (F) is also present in cytoid bodies but in a lesser amount; it is characteristically deposited on and along the basal lamina and its reduplications in the uppermost strata of the dermis. Our results indicate that IgM deposition in cytoid bodies occurs at a very early stage during the formation of these structures and that fibrinogen exhibits a specific affinity not only to cytoid bodies but also to basal lamina material.


Inflammatory macular atrophy: immunofluorescent and ultrastructural findings. In a patient with primary inflammatory macular atrophy, immunofluorescence studies disclosed both C'3 and IgM in a granular and fibrillar pattern in the dermis between the coagen fibers and at the basement membrane zone. Localization of C'3 to autofluorescent elastic fibers was demonstrated. Ultrastructural examination showed the presence of activated macrophages enveloping fragmented elastic fibers. Immunologic mechanisms may play a participatory role in some forms of macular atrophy.


Computed tomography of ancient Egyptian mummies. This first report of the application of computed tomography (CT) to the study of ancient mummies, the desiccated brain of a boy and the body of a young woman within her cartonnage, shows that CT is uniquely suitable for the study of such antiquities, a study that does not necessitate destruction of the mummy or its cartonnage. Exquisite images result that are of great paleoanatomical, paleopathological, and archeological significance.


Abnormal gonadothrophin secretion in children with chronic renal failure. LH and FSH response to intravenous injection of GnRH was evaluated in a group of patients with chronic renal failure on intermittent haemodialysis and in two children with successful renal transplant. Basal plasma LH was elevated in children with chronic renal failure as compared to control, and significantly increased following GnRH injection in most of the children. Basal plasma FSH was higher than in the control group, and slightly increased after GnRH. These data suggest an abnormal response to GnRH in chronic renal failure and an involvement of hypothalamus and pituitary in chronic renal disease. The role of abnormal gonadotrophin secretion in growth retardation and pubertal delay of these children is still not well understood.


The effect of renal transplantation on plasma protein binding. The in vitro plasma protein binding was determined in nine maintenance hemodialysis patients who later underwent renal transplantation. The organic acid fluorescein (10 micrograms/ml) or the organic base quinidine (5 micrograms/ml) was added to the pre and post transplant serum of these patients. Drug concentrations were measured spectrophotofluorometrically after equilibrium dialysis. The results were compared with the plasma protein binding of eight normal volunteers. The patients on maintenance hemodialysis had lower plasma protein binding of fluorescein than normals (78 +/- 5% vs 89 +/- 4, p less than 0.001). Plasma protein binding improved significantly after renal transplantation (85 +/- 3, p less than 0.01) but was still lower than in normals (p 0.05). Plasma protein binding of quinidine was not significantly different than in normal volunteers (77 +/- 8%) either prior to (72 +/- 10%) or after (73 +/- 12%) kidney transplantation. Plasma protein binding of quinidine remains unaffected by renal transplantation. However, the abnormal plasma protein binding or organic acids in chronic renal failure may be significantly improved by renal transplantation.


Immunofluorescent detection of actin and myosin in healing gingival epithelium. Indirect immunofluorescent labeling shows a sequential increase in detectable epithelial cell actin and myosin during wound repair migration and maturation. While actin shows a substantial increase between pre-wound and migration levels, the relative detectable myosin is omnipresent at apparently high levels, and it increases only slightly during active migration.


Ridit analysis in dental clinical studies. Ridit analysis is presented as an appropriate method of analyzing dental clinical data which fall somewhere between the purely categorical (e.g., improved vs. not improved) and the bona fide quantitative (e.g., mg % salivary calcium) scales of measurement. The key feature of the method is the estimation of the probability that a randomly-selected patient from one treatment group is "better-off" than a randomly-selected patient from another. Methods are presented for testing statistical significance and constructing confidence intervals. The method is illustrated on data from a comparative clinical trial of ibuprofen, aspirin and placebo in the relief of post-extraction pain. There were no significant differences in efficacy among the active treatments, but each was significantly superior to placebo.


Phase changes in base metal alloys along metal-porcelain interfaces. Five commercial, base metal alloys used with porcelain were investigated. After oxidizing heat treatments and the porcelain bake, phase changes occurred in some alloys near the porcelain interface. These changes were due to the depletion of the matrix in alloying elements as a result of the oxidizing treatments.


Fit of porcelain fused-to-metal crown and bridge castings. The dimensional accuracy of porcelain fused to metal crown and bridge castings was determined on truncated cone-shaped steel dies. Ni-Cr castings produced in manufacturers' laboratories were consistently undersize, while precious metal castings were consistently oversize. Ni-Cr castings, produced in NBS laboratories using a modified investing technique, were routinely oversize.


Transmission and control of dentinal pain: resin impregnation for the desensitization of dentin. With the exception of direct electrical stimulation, it seems that all procedures known to produce dentinal pain may mechanically distort the structure of pain-sensitive nerves in the pulp and predentinal area and that this effect is mediated by a hydrodynamic link. Nature may contribute to insensitive dentin by: production of irregular, atubular dentin at the pulpal wall; obliteration of dentinal tubules by sclerosis; and mineralization of a superficial layer, pellicle or plaque, at the exposed surface. Few clinical methods are capable of accelerating these mechanisms. A technique of resin impregnation for the desensitization of exposed dentin has been presented. After proper pretreatment, that includes drying the dentin surface, resin tags can be obtained in the outer part of the dentinal tubules and may immediately and permanently relieve dentinal pain. This technique seems to be a good alternative to other methods, especially for patients with occlusal or incisal exposures caused by abrasion, grinding, or fracture, in which other methods cannot provide immediate and long-lasting desensitization.


Effectiveness of a pit and fissure sealant in the prevention of caries: three-year clinical results. With use of the half-mouth technique, a pit and fissure sealant was applied to the permanent first molars of 200 children between 6 and 8 years of age in a community with fluoridated water in Colombia, South America. Complete retention of sealant at 12, 24, and 36 months after application was 91.6%, 88.9%, and 87.5%, respectively. Partial retention of sealant was 5.8%, 7.1%, and 8.5% at the same intervals. The incidence of caries in all sealant-treated teeth at 36 months was 8% vs 53% in untreated paired teeth. Of the 238 teeth that completely retained sealant, only one tooth had occlusal caries at 36 months. No statistically significant difference in complete retention between maxillary and mandibular molars was noticed at any examination. The study confirms that this cold-cured pit and fissure sealant is effective in protecting the occlusal surfaces of teeth against caries for at least three years.


Extensive caries in early man circa 110,000 years before present. The example of Rhodesian man, who was approximately 35 years at time of death, had severe caries but physiologically adaptive attrition and periodontal status. Hypoplasia was not evident. Extensive caries seems to have occurred in the absence of modern bacterial strains and refined carbohydrates. It is suggested that the dentition was highly susceptible to caries because of a deficiency in elemental composition. Of the teeth examined, only the central incisors were free of caries and apparently resistant to disease. It is postulated that, as dental disease progressed, the Rhodesian man's diet changed and his techniques and abilities in processing food developed.


Reducing marginal leakage: a review of materials and techniques. Although significant progress has been made with the advent of composite restorative materials and associated techniques, the problem of marginal leakage has been lessened but not solved. The primary aim of future work must still be directed toward preventing the formation of a gap between the restoration and the tooth.


Vitamin E content of foods.

Vitamin E content of foods. Tables showing representative values for the vitamin E content of human foods have been developed from all the available reliable information. These tables cover animal products, plant products, fats and oils, baked products, infant foods, and mixed dishes. The effects on vitamin E content are discussed for heating and storage of dairy products, grains, vegetables, and plant oils; for the refining of plant oils; and for the processing and baking of grain products. Causes of variation in vitamin E levels are presented and the distribution of the different forms of vitamin E in foods is shown. The biologic activities of these forms are used to calculate approximate vitamin activity values of representative foods.


Studies of immunoreactivity to human lacrimal gland fractions in patients with ophthalmic Graves' disease. In vitro evidence for immunoreactivity against human lacrimal gland fractions was sought in patients with ophthalmic Graves' disease. There was no significant increase in interstitial lymphoid tissue on lacrimal gland biopsy. Serum antibodies against lacrimal fractions were not detected using the indirect immunofluorescent technique. Using the tanned cell hemagglutination test with lacrimal antigen, antibodies were detected in 2 of 15 patients with eye disease, 2 of 15 hyperthyroid patients without eye disease, and 2 of 20 normal subjects. Macrophage inhibitory factor (MIF) production in response to human lacrimal extract was not demonstrated in any of 11 patients with eye disease tested. On the other hand, MIF was demonstrated in 2 of 10 patients with Graves' disease selected for absence of eye disease. Significant peripheral blood lymphocyte transformation in response to human lacrimal extract, or a soluble or membrane fraction, was demonstrated in 9 of 22 patients tested; in 6 of 21 patients to extract, in 3 of 21 patients to a soluble fraction and in 7 of 10 patients to a membrane fraction. The possible significance of lacrimal gland inflammation and role(s) in the pathogenesis of ophthalmic Graves' disease are discussed.


Immunofluorescent localization of pea storage proteins in glycol methacrylate embedded tissue. Improved immunofluorescent techniques have been developed for the high resolution light microscopic localization of intracellular antigens in plant tissue. Thin sections of pea cotyledon tissue which had been fixed in paraformaldehyde and embedded in glycol methacrylate were reacted with mono-specific antibodies to the storage proteins legumin and vicilin. These antibodies were raised in sheep, purified by affinity chromatography and tested by immunoelectrophoresis and immunodiffusion. Using the indirect technique, rhodamine-labeled antibodies permitted specific fluorescent localization of the legumin and vicilin to small (ca. 1 micrometer) cytoplasmic organelles in near mature tissue. Subsequent histochemical staining verified the proteinaceous nature of these organelles. Parameters affecting staining specificity and background fluorescence are discussed.


An immunoferritin labeling study of H-2 antigens on dissociated epithelial cells. This report describes an immunoferritin labeling study of mouse H-2 histocompatibility antigens on epithelial cells dissociated from stomach, duodenum-jejunum, ileum, trachea, diestrus uterus, gall bladder, and vas deferens. Before cell dissociation, most of the organs were prefixed in periodate-lysine-paraformaldehyde to preserve the shape of the cells and to immobilize H-2 antigens in their native positions. Five kinds of epithelial cells expressed H-2 antigens on lateral and basal membranes but not on apical membranes. These were the lining cells of the upper intestine, ileum, gall gladder, uterus, and the tracheal brush cell. The antigens were continuously distributed on the lateral and basal membranes of these cells and appeared to be absent from the apical membranes, rather than masked by the fuzzy coat. On four other epithelial cell types H-2 antigens could not be detected. These were the lining cells of the vas deferens, parietal and chief cells from the stomach, and ciliated tracheal cells. It does not seem to be uncommon for normal nucleated cells to lack H-2 antigens. On fixed and labeled epithelial cells from the upper intestine the zonula occludens membranes were unlabeled, while the zonula adherens and desmosome membranes were labeled as densely as the remainder of the lateral membranes. The zonula occludens membrane thus constituted the boundary betewen the unlabeled apical membrane and the labeled lateral membrane of these cells. Intestinal epithelial cells dissociated without prefixation showed a patchy distribution of H-2 antigens on their lateral membranes after indirect labeling, indicating antigen mobility in this membrane. On the same unfixed dissociated cells the antigens were able to migrate from lateral to apical membranes, a movement which appears to be prevented in the intact epithelial layer by the occluding junction. The absence of H-2 antigens from apical membranes and their inability to migrate through an intact zonula occludens suggest that these molecules must reach the lateral membranes of epithelial cells by a pathway which is distinct from that followed by apical membrane components.


A method for enumeration ot T and B lymphocytes in tissues. A method for the identification of T and B lymphocytes in tissue specimens is described. A sonication technique results in viable relatively pure lymphocyte populations which are easily classified by their surface markers. This readily reproducible method can become a standard laboratory procedure in the evaluation of disease states which require such information related to the classification of lymphocyte cell origin.


Peroxisomes in disease.

Peroxisomes in disease. Cytochemical, biochemical and morphological changes in peroxisomes have been described in human metabolic disorders, in experimental models of disease and in response to drugs and toxins. These include the cerebrohepatorenal syndromes, in which peroxisomes can not be detected and mitochondrial respiration is inhibited, atherosclerosis, alcoholic cardiomyopathy, and tolerance to oxygen toxicity. Although information on the role of peroxisomes in disease is limited, increased awareness of their widespread distribution and the availability of an improved cytochemical procedure for staining peroxisomes in human specimens should provide new insights into their function.


Somatostatin-immunoreactive nerve cell bodies and fibers in the medulla oblongata et spinalis. Complete serial sectioning of the medulla oblongata in monkey, cat, guinea pig, and japanese dancing mouse and incubation for somatostatin-immunoreaction was carried out. Numerous regions of the medulla oblongata such as the nucleus reticularis gigantocellularis, nucleus cuneatus et gracillis, nucleus raphe magnus, nucleus tractus solitarius, nucleus vestibularis, and parts of the oliva contain dense networks of somatostatin-immunoreactive nerve fibers. Cell bodies were seen in the nucleus reticularis medullae oblongatae. In the spinal cord the sections from each segment were analyzed, showing the highest concentrations of somatostatinergic fibers in the substantia gelantinosa of the columna dorsalis. Cell bodies were seen in the zona intermedia centralis, especially in the upper cervical segments. Many positive fibers were also seen in the entire zona intermedia and the columna ventralis. Especially prominent was the immunoreactivity in the zona intermediolateralis of the thoracic segments and the columna ventralis of the lower lumbar and sacral segments.


Further studies on the sources of Klebsiella aerogenes in hospital patients. We report an investigation into faecal carriage of Klebsiella aerogenes and the distribution of this organism in the environment of three wards. In all three wards faecal carriage rates were high (60-70%). The faecal carriage rate increased with antibiotic administration and with length of in-patient stay. K. aerogenes was widely distributed in the ward environment and was found on the hands of nursing staff. Clusters of isolations of K. aerogenes of the same serotype were demonstrated indicating either patient-to-patient transfer or a common source of infection. The results indicate that even under conditions in which there are no outbreaks of K. aerogenes infection, there is a large reservoir of this organism both in the bowel of patients and in the ward environment.


Salmonella isolation from hospital areas. Evidence of the presence of salmonellas in a paediatric ward, a special care baby unit, a maternity unit and a hospital kitchen was obtained by culture of sewer swabs, faeces and food samples. The survey was designed to cause as little administrative interference as possible. The technical aspects of the survey did not strain laboratory facilities. Minimal secondary spread of salmonella infection was experienced.


Stool viruses in babies in Glasgow. 3. Community studies. Twenty-seven babies from one deprived housing area in Glasgow were followed-up regularly, for periods varying between 2 months and 11 months (mean 7 months), in a prospective study of the viruses to be found in their stools by electron microscopy. Weekly stool specimens were collected in the home together with a history of the baby's health. Additional stool specimens were obtained, up to a maximum of one per day, during admissions to hospital. Over 500 specimens were obtained at home and another 320 in hospital. A wide variety of viruses (over 200 recognizates) were detected and it has been possible to plot their temporal relation to disease episodes. It became apparent that virus excretion was frequently unaccompanied by evidence of illness and it has not been possible to describe a typical illness syndrome associated with any of the morphological types of virus observed. The results suggest that, in one area of Glasgow at least, patterns of virus excretion in young babies are complex and will need further elucidation before the need for a vaccine to prevent infantile diarrhoea could be defined.


The effect of an intramammary infusion of endotoxin on experimentally induced mycoplasmal mastitis. The infusion of 10 microgram of endotoxin lipopolysaccharide from Escherichia coli into the mammary gland of four cows 16 h before inoculation with ureaplasmas did not prevent, or even diminish, the subsequent ureaplasmal mastitis. There was no reduction in the severity or duration of the inflammatory cell response in milk or in the clinical appearance of the resulting mastitis. Also, the excretion of ureaplasmas was not reduced. A similar experiment with Mycoplasma dispar in two cows demonstrated that endotoxin was again ineffective in preventing the mastitis. Furthermore, there was some indication that the proliferation and excretion of this mycoplasma was enhanced in endotoxin-treated quarters.


The occurrence of plasmids carrying genes for both enterotoxin production and drug resistance in Escherichia coli of human origin. Twenty-three of 89 enterotoxigenic strains of Escherichia coli were resistant to one or more antimicrobial agents. Eleven strains transferred resistance directly and five transferred resistance after mobilization. In three cases a resistant recipient was enterotoxigenic. One of these strains contained a conjugative plasmid carrying genes for both drug resistance and enterotoxin production. In the two other strains genes for drug resistance and enterotoxin production were carried on separate co-transferable plasmids.


Nephelometric detection of circulating immune complexes using monoclonal rheumatoid factor. A nephelometric technique for the estimation of immune complexes (IC) in serum was developed using purified monoclonal rheumatoid factor from a human patient (mRhF) specific for complexed IgG. Standardisation of the assay was carried out with heat aggregated normal human IgG as a model complex and with IC composed in vitro from ovalbumin and rabbit antisera to ovalbumin. The nephelometric method was compared with [125I]Clq radioimmunoassay (C1q RIA). The lower limits of detection by the two methods were similar for both aggregated IgG and performed ovalbumin/rabbit anti-ovalbumin IC. However, recognition of IC by the two methods differed with different ratios of antigen and antibody. When IC were formed at 10 times antigen excess the nephelometric technique was more sensitive than when IC were formed at equivalence or 10 times antibody excess. The Cuq RIA method was most sensitive in detection of IC in antibody excess but failed to detect IC in antigen excess. Complexes formed in antigen excess also showed potentiated light scattering when 1.5% polyethylene glycol was used in the nephelometric system. The incidence of IC detected by the mRhF in sera from patients with rheumatoid arthritis and systemic lupus erythematosus was lower than with C1q RIA suggesting that the IC in these patients contain antibodies not detected by the mRhF used. IC in the sera of patients with melanoma were detected more frequently by the mRhF assay which may indicate the IC in these sera were in antigen excess. Detection of IC by mRhF nephelometry was rapid, technically simple and yielded results which complemented those of the established C1q RIA method. This assay system is a useful addition to methods currently available for detection of IC and the similar use of rheumatoid factors against different classes of antibody should extend its usefulness.


A technique for the purification of immune complexes using rheumatoid factor. A method for the purification of immune complexes (IC) from human serum is described, using as a model complexes of tetanus toxoid with human antitoxoid antibodies (TAT). The technique is based on the ability of IC to bind to tubes coated with rheumatoid factor (RF). Small amounts of TAT IC were added to human serum and the mixtures were rotated overnight in tubes coated with RF. The tubes were then washed and the bound material was eluted with sodium dodecyl sulphate and iodinated with 125I. Analysis of the labeled preparation by electrophoresis in polyacrylamide gels revealed the presence of the toxoid component. The technique should be useful in isolating small amounts of IC for analytical purposes.


A novel technique for detecting IgA coated potentially pathogenic microorganisms in the human intestine. This paper describes a novel method for detecting immunoglobulin A (IgA) coated potentially pathogenic microorganisms (PPMs) in the human intestine. Essentially, the technique consists of 2 phases: one in which IgA coated bacteria are detected by immunofluorescence and a second in which these bacteria are subcultured in situ and subsequently identified. In this way transient bacteria are differentiated from resident bacteria. These results show that the resident bacteria are coated with IgA. Resident microorganisms are always highly concentrated in the digestive tract. These results strengthen the hypothesis that only the high antigen concentrations achieved by a large number of resident bacteria are capable of IgA induction.


Observations on the validation of immunochemical assays of monoclonal immunoglobulins. Assays of specific immunoglobulins by immunochemical methods are subject to a well-documented discrepancy when the test sample contains a monoclonal immunoglobulin of the class under assay. Demonstration of parallelism of the polyclonal standard and test sample log dose-response curves if proposed as an essential step in the validation of such assays, but theoretical considerations suggest that the mechanism underlying the observed discrepancy is unlikely to be associated with non-parallelism. The examination of 50 samples containing monoclonal immunoglobulins provides no evidence for rejecting the theoretical conclusions. It is shown here that demonstration of parallelism is of no value in establishing the validity of monoclonal immunoglobulin assays by immunochemical methods. The observation of relative changes in paraprotein concentration using an initial myeloma serum from the same subject as an arbitrary reference point is criticised.


T-lymphocyte rosette inhibition titering of antisera by direct microassay. A 60-sample micro-rosette inhibition assay for determining the 100% rosette inhibitory titers of heterologous antisera is described. The assay is performed in histocompatibility trays, under oil, using frozen-thawed thymocytes or peripheral blood lymphocytes for an appropriate period, either with or without added complement; SRBC are inoculated into each well, and rosettes formed by centrifugation of the trays at 200 x g. following centrifugation, glutaraldehyde is added to each well to fix rosettes to the well bottom and the plates inverted to allow unbound SRBC to fall away. One hundred percent rosette inhibition is determined by low power microscopic examination of the inverted wells. Highly reproducible in-assay (+/-4% average standard error) and between-assay (+/-9%) inhibition values are obtained which correlated well (r = 0.99) with values calculated by more conventional methodology.


Aggregated human immunoglobulin G stabilized by albumin: a standard for immune complex detection. Stabilized preparations of heat-aggregated human immunoglobulin G (A-IgG) of restricted size were made by separating A-IgG by sucrose density gradient ultracentrifugation in the presence of bovine serum albumin (BSA). Periodic recentrifugation of stored fractions of the radiolabelled A-IgG indicated that the initial sedimentation characteristics were preserved. Pooled fractions of A-IgG stored for up to 16 months had the same functional activity as freshly prepared A-IgG of corresponding size when assessed by activation of the first component of complement and consumption of C4 and CH50 in normal human serum. It was also found that the reactivity of A-IgG in the C1q binding assay (C1Q-BA) and the conglutinin binding assay (Con-BA) was not altered by long-term storage of these A-IgG. Testing different batches of [125I]C1q and conglutinin with the same batch of stabilized A-IgG showed variations due to the instability of both [125I]C1q and conglutinin. The influence of these variations on the quantification of the levels of immune complexes in sera was reduced by using stable A-IgG as a reference. The assays were compared to determine the effect of the size of the aggregate. The C1Q-BA detected preferentially A-IgG of large size, while size had no influence in the Con-BA. These results suggest that the stability of A-IgG in BSA is such that this preparation may be used as a reliable standard for immune complex assays.


Uncovered skin grafts in mice.

Uncovered skin grafts in mice. A technique for suturing ear skin on the lateral thoracic area of recipient mice is described. Using this technique the graft was visible from the day of grafting until rejection was complete and mice were not burdened by circumferential body dressings. Consistent mean survival times were observed in a donor-recipient combination over 1 year's time and technical failures could be recognized. This technique was useful to accurately assess accelerated rejection responses in normal mice that occur 4-8 days after grafting as a result of passively transferred effector cells.


A simple method for the detection and assay of C1. A simple method is described for the production of human serum deficient in the complement component C1. This C1-deficient serum can be used for the assay of C1. If the amount of C1 is expressed in terms of its subcomponent C1q, the method can detect C1 when the C1q subcomponent content is only 10 pg.


Control of excitation in the fluorescence microscope. In fluorescence microscopy image brightness and contrast and the rate of fading depend upon the intensity of illumination of the specimen. An iris diaphragm or neutral density filters may be used to reduce fluorescence excitation. Also the excitation bandwidth may be varied by using a broad band exciter filter with a set of interchangeable yellow glass filters at the lamphouse.


Demonstration of the complement regulating protein, beta 1H, in skin biopsies from patients with bullous pemphigoid. beta 1H-globulin is a recently characterized plasma protein which regulates the biologic activities of the major fragment of the third complement component, C3b. The major function of this protein is to act as a co-factor for C3b Inactivator (C3bINA) in the cleavage of C3b to an intermediate molecule, C3b', consisting of an intact beta-chain covalently bound by disulfide bridges to 2 alpha-chain fragments of 40,000 and 67,000 daltons. Final cleavage of C3b' to the C3c and C3d fragments requires an additional protease such as plasmin or elastase. Additionally, beta 1H interferes with the activity of the alternative pathway convertases, C3bBb and C3bBbP, by displacing or competing with the binding of factor B. In this study, perilesional skin biopsies from 10 patients with active bullous pemphigoid were examined for the presence of beta 1H at the dermal-epidermal junction by immunofluorescent methods. The protein was found in 8 of 9 biopsies in which C3 also was deposited. In a single case where C3 was not found, beta 1H was not seen. These findings suggest that beta 1H plays a role in the in vivo control of C3b and provides additional evidence for the participation of the complement system in the pathogenesis of bullous pemphigoid.


Diagnosis of bacterial meningitis by gas-liquid chromatography. I. Chemotyping studies of Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, Staphylococcus aureus, and Escherichia coli. With the use of gas-liquid chromatographic techniques, the chemical characteristics of Streptococcus pneumoniae type 3, Escherichia coli, group B Neisseria meningitidis, Haemophilus influenzae type b, and Staphylococcus aureus, organisms that commonly cause bacterial meningitis, were identified. The combination of lipid, carbohydrate, and lipopolysaccharide components provided discriminating markers for chemotyping these bacteria. E. coli had a high content of 17- and 19-carbon cyclopropane fatty acids, whereas none of the other organisms tested revealed any cyclic acids, apart from a possible trace amount in S. pneumoniae. The content of isomethyl branching fatty acids clearly distinguished S. pneumoniae and S. aureus. N. meningitidis and H. influenzae were somewhat similar in their overall fatty acid compositions, but the presence of galactose without rhamnose in extracts of N. meningitidis readily distinguished N. meningitidis from H. influenzae. Only extracts from E. coli contained mannose; erythrose was an exclusive marker in extracts of S. pneumoniae. These data suggest that these differences in chemotype might be useful in developing a gas-liquid chromatographic assay of spinal fluid for the rapid laboratory diagnosis of bacterial meningitis.


Meningitis caused by Haemophilus influenzae in infant rats: protective immunity and antibody priming by gastrointestinal colonization with Escherichia coli. Infant rats aged five to seven days were fed Escherichia coli O75:K100:H5, E. coli O13:K92:H4, or saline and five weeks later were inoculated with Haemophilus influenzae type b. The incidence of bacteremia and meningitis was significantly less (P less than 0.05) for rats fed E. coli that possessed K100 capsular antigen (cross-reactive with type b capsular antigen) than for rats fed E. coli K92 or saline. Antibody to capsular antigen was not detectable in sera obtained from rats prior to challenge with H. influenzae type b, but five days after challenge, antibody levels were significantly higher (P less than 0.001) in rats colonized with E. coli K100 than in controls. These results, together with data from passive-immunization studies, suggested that the protection against infection with H. influenzae type b was due to priming or serum anticapsular antibody, although a protective role for cell-mediated immunity and/or secretory antibody could not be ruled out. E. coli K100 primed rats vaccinated with purified H. influenzae type b antigen for a significantly increased, although transient, anticapsular antibody response.


Identification of patients with increased risk of infection with herpes simplex virus after renal transplantation. Forty-nine recipients of renal allografts were studied for infection with herpes simplex virus (HSV) before and at sequential intervals after transplantation. Forty-four (90%) of the patients studied were initially seropositive for neutralizing antibody to HSV type 1. HSV was not shed prior to transplantation nor by any of the five seronegative recipients after transplantation. Twenty-nine (66%) of the 44 seropositive patients shed virus postoperatively: 23 in saliva, three in urine, and three in both sites. Twenty (63%) of 32 seropositive patients examined developed herpetic mucocutaneous lesions. Both viral shedding and lesions were most prevalent during the first four weeks after transplantation. Twenty-nine (85%) of 34 patients with antibody titers of 1:256-1:4,096 and zero of 10 with titers of 1:8-1:128 shed HSV postoperatively (P less than 0.0001). The group with high antibody titers before transplantation were also more likely to develop lesions after transplantation (P = 0.002) as were those with a positive history (P = 0.017). The ability to predict symptomatic HSV recurrences in renal transplant patients could be a valuable aid in identifying individuals with which to evaluate antiviral compounds.


Host defense in cryptococcosis. III. Protection of nude mice by thymus transplantation. Congenitally athymic (nude) BALB/c mice, which are homozygous for the nu gene, are extremely susceptible to challenge with Cryptococcus neoformans. Groups of nude mice received transplants of thymus tissue obtained from either heterozygous (nu/+) mice or normal BALB/c mice not carrying the nu gene. Survival and delayed-type hypersensitivity were measured after challenge with cryptococci. Mice that received thymus tissue from a heterozygous (nu/+) or normal BALB/c mouse donor had markedly prolonged survival after challenge. In addition, mice that received thymus tissue from normal BALB/c mice developed delayed-type hypersensitivity to cryptococcal antigens following challenge. These studies indicate that transplantation of thymus tissue effectively increases host immune resistance against C. neoformans.


Effect of antibiotics on the adherence of enterobacteriaceae to human buccal cells. Antibiotics at bacteriostatic concentrations (four times the minimal inhibitory concentration) decreased the attachment of Enterobacteriaceae to human buccal cells in vitro and augmented the reversibility of such adherence. These actions of antibiotics may influence colonization by nosocomial bacteria and the subsequent infection that they cause.


Evidence for enterotoxin production by a classic enteropathogenic serotype of Escherichia coli. Isolates of classic enteropathogenic Escherichia coli O:128 that had been implicated in an outbreak of diarrhea in a hospital nursery were found to produce heat-stable enterotoxin after storage for six years. This finding indicated that enteropathogenicity and the ability to produce enterotoxin may coincide in E. coli, and further study of enteropathogenic strains that produce enterotoxin may help in elucidation of the relationship between enteropathogenic and enterotoxigenic E. coli.


Comparison of techniques for measurement of in vitro antibiotic synergism. The methods and criteria for testing for synergy were compared with use of 22 strains of Klebsiella pneumoniae and a combination of cephalothin and gentamicin. With the checkerboard technique, the frequency of synergy varied depending on the criterion employed. When the rate of killing of bacteria by antibiotics was measured, results varied depending on the size of inoculum. When the checkerboard and killing-curve techniques were compared, there was poor correlation in terms of the frequency of strains showing synergy. Because clinical observations suggest that treatment of serious infections with combinations of antibiotics found to be synergistic in vitro may enhance survival, standardization of the methods and criteria used to test for synergy should be undertaken.


Transmission and scanning electron microscopic studies of rhinoscleroma. Using both types of electron microscope, combined transmission and scanning electron microscopic studies were done on 6 patients with rhinoscleroma. The present work suggests the possibility of two types of organisms causing the disease: one type--being in the majority--was a rod-shaped bacillus measuring about 3 micrometers; the other type was a short, stout bacillus with terminal spiral cilia. The ultrastructure of these bacilli has been described. The advantages and limitations of each type of electron microscopy in the investigation of rhinoscleroma have been discussed.


Electrocardiography in myocardial infarction. Electrocardiography is an evolving clinical diagnostic modality for detection of acute myocardial infarction. Animal studies and electrocardiographic-clinical-pathological correlations have provided experience currently used for detection and rough localization of myocardial infarcts. Additions to the conventional 12 electrocardiographic leads have been utilized to increase the diagnostic sensitivity of the ECG in the setting of myocardial infarction. Mapping of ST-segment elevation an QRS complex from several chest wall loci have been employed for purposes of quantitating serially myocardial ischemic injury and eventual necrosis. These multiple lead electrocardiographic systems have also been utilized in assessing therapeutic interventions in the Coronary Care Unit. Usefulness of standard and multiple-lead recording systems is enhanced by awareness of their limitations when applied to patients with acute myocardial infarction.


I. V. Zavadskii and the beginnings of behavioral pharmacology: an historical note and translation. I. V. Zavadskii, who worked in Pavlov's laboratory between 1907 and 1909, performed a study that has many of the characteristics of modern behavioral pharmacology. He studied the effects of alcohol, morphine, cocaine and caffeine on the conditioned salivary reflex. A translation of his paper and some brief comments on his life are presented.


A comparative survey of the function, mechanism and control of cellular oscillators. This review attempts to survey in a uniform manner the available evidence concerning the generation and behaviour of several well-investigated cellular oscillators. Members of two broad classifications are contrasted: (i) cytoplasmic oscillations, where the periodic phenomena is generated by an instability pathway and (ii) membrane oscillators in which a membrane potential rhythm is generated at the membrane. Interactions between the cytoplasmic and membrane compartments are considered and the effects of these interactions on oscillatory behaviour is discussed. Because of their biological importance and the greater body of experimental results, particular attention is directed to a study of membrane potential oscillations. These systems can be approximately classified in two groups: (i) systems in which a periodic potential results from oscillatory changes in permeability and (ii) systems in which potential oscillations result from the periodic activity of an electrogenic pump. The examples considered include the glycolytic oscillator, oscillations in vein contraction in the slime mould Physarum polycephalum, rhythmic aggregation in Dictyostelium discoideum, neural oscillators, the periodic potential in Purkinje fibres and the sino-atrial node and rhythmic behaviour in smooth muscle. Questions considered include the generation of periodic activity, the modulation of the oscillation by drugs and other metabolic and membrane effectors and the question of the functional role of these oscillations.


Dynamic oscillations in the membrane potential of pancreatic islet cells. Glucose and other metabolizable sugars which elicit insulin release from the beta-cell of the pancreatic islet induce repetitive oscillations in the beta-cell transmembrane potential. Upon each phasic depolarization are superimposed rapid fluctuations in potentials, i.e. 'action potentials' or 'spikes' which occur as bursts of electrical activity; the duration and frequency of each burst is a function of glucose concentration. These established electrophysiological features of glucose-islet cell interaction are described in detail together with a consideration of their possible molecular and ionic basis. Based on these observations, a dynamic mathematical computer model of the beta-cell membrane electrical behaviour is presented which utilizes the Goldman equation extended to include divalent ions. The model illustrates how the ionic mechanisms deduced from experimental observations can account for the electrical patterns produced by the beta-cells in the presence of D-glucose; it also allows systematic changes to be made in a number of state variables in order to assess their relative importance and possible contribution to the integrated processes actually observed. Finally, distinction is made between aspects of the model which are well supported by experimental results and those areas which require further analysis.


Human immune response to immunization with a structurally defined polypeptide fragment of streptococcal M protein. We tested the ability of pepsin-extracted, highly purified M protein to induce type-specific immunity in experimental animals and humans. M protein was prepared from limited peptic digests of whole group A type 24 streptococci and was purified to chemical homogeneity as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, quantitative amino acid analysis, and Edman degradation. For vaccination, the lyophilized M24 protein preparation (pep M24) was precipitated in aluminum hydroxide. When injected into laboratory animals, alum-precipitated pep M24 produced type-specific protective antibodies and was free of non-type-specific immunoreactivity. In man, skin tests with 1-microgram doses of pep M24 were negative in all 37 adults tested. 12 adult human volunteers received two-four subcutaneous injections of 100-200 micrograms of alum-precipitated pep M24 at intervals of at least 2 wk. The immune response to pep M24 was measured by a variety of assays designed to detect (a) type-specific humoral antibodies (opsonophagocytic, long chain, and mouse protection tests); (b) total humoral antibodies (complement fixation and enzyme-linked immunosorbent assay); (c) cellular immunity (skin tests); and (d) heart cross-reactive antibodies (immunofluorescence). Type-specific opsonic antibodies developed in 10 of the 12 vaccinees, and positive delayed-type skin tests developed in 11. Immune sera from two of the vaccinees were effective in mouse-protection tests against challenge with M24 but not M6 streptococci. None of the volunteers developed heart-reactive antibodies or antibodies to non-type-specific M protein antigens. Alum-precipitated pep M24 was well-tolerated in man, and no serious local or systemic reactions were observed. Thus, pep M24 induces type-specific, protective antibodies in doses that are well-tolerated in man.


A hemolytic plaque assay for activated murine T cells. In an earlier report, it was shown that murine spleen cells cultured with concanavalin A (Con A) released into the culture supernatants helper and suppressor substances for antibody production. The present communication describes the production of rabbit antisera against culture supernates from Con A-activated spleen cells and their use in a plaque assay for mitogen-activated T cells. The plaque assay, utilizing SRBC to which Staphylococcal protein A had been coupled, the developing anti-supernatant antiserum and guinea pig complement, readily detected secreting T cells. The T-cell nature of the plaque-forming cells (PFC) was established principally by the following: (a) the majority of lymphocytes in the centers of plaques were Thy-1-positive by fluroescence; (b) spleen cells depleted of B cells by incubation in plastic dishes coated with rabbit anti-mouse Ig antibody gave greatly enriched PFC responses; (c) anti-Thy-1 and anti-Lyt-2.2 treatment of spleen cells almost completely depleted PFC; (d) T-cell mitogens (Con A and phytohemagglutinin) but not B-cell mitogens (lipopolysaccharides) induced PFC responses; (e) T cells maintained in culture for 10 d with Con A and T-cell growth factor yielded PFC. Kinetic and dose response studies showed that high doses of mitogen induced rapidly appearing T-PFC and the responses peaked at day 1--2 of culture. Lower doses of mitogen-induced PFC required longer periods of incubation for detection, indicating that cell activation and secretion may be different dose-dependent activities of mitogens. Another noteworthy finding was that the antiserum reacted with surface antigens of T-PFC, indicating that secreted products are expressed on the membranes of T cells, offering the possibility of isolating populations of cells with specific secretory potential. Although the precise nature of the T-cell products detected by the antiserum used in this assay are unresolved, 10% of the target-cell-adherent population from spleen cells of BALB/c mice sensitized to L929 cells formed plaques. This suggests that the antiserum has significant activity against the products of cytotoxic T cells, a finding which accords with the activity of anti-Lyt-2.2 serum against mitogen-induced T-PFC. The method clearly offers new possibilities for the analysis of T cells and their products and should provide an important approach to the clonal analysis of lymphokine production.


Interactions between human eosinophils and schistosomula of Schistosoma mansoni. II. The mechanism of irreversible eosinophil adherence. Previous work (1)(1) has shown that normal human eosinophils show a preferential capacity, in comparison with neutrophils, to bind to antibody- coated schistosomula of Schistosoma mansoni. This effect is attributable to a temperature-dependent function of the eosinophil which renders its binding stable and irreversible by aggregated gamma globulin or Staphylococcus aureus protein A. In contrast, the binding of neutrophils is readily reversible by these agents. It has now been shown that the differences observed between eosinophils and neutrophils is a property of their interaction with living schistosomula. When dead or artificially damaged schistosomula were tested, neutrophils showed a markedly enhanced capacity to adhere, in both the presence and absence of anti-chistosomular serum. Subsequent experiments were designed to test the hypothesis that the strong, stable binding of eosinophils was attributable to degranulation, with release of granule contents which would then serve as ligands to bind the cell to the organism. First, an enhanced adherence both of eosinophils and of neutrophils could be demonstrated in the presence of eosinophil major basic protein (MBP) or of protamine, a high molecular weight cation. Second, the binding of eosinophils induced by concanavalin A (Con A) was found to differ markedly from that induced by antischistosomular serum. Con A-mediated binding of eosinophils was fully reversible by alpha-methyl-mannoside, was not associated with damage to the organism, and did not lead to degranulation of the cell, as estimated by measuring the release of MBP into the culture supernate. However, induction of degranulation of concanavalin A-bound eosinophils, but not of neutrophils, with the calcium ionophore A23187 converted the reaction into one which was no longer reversible by alpha- methylmannoside and in which damage to the organism now did occur. These findings support the hypothesis that the stable binding of eosinophils is associated with degranulation, a process which may contribute to the preferential capacity of this cell to mediate antibody-dependent damage to schistosomula.


Characterization and localization of the enzymatic deacylation of lipoteichoic acid in group A streptococci. Protoplasts of a group A streptococcal strain were shown to contain enzymatic activity capable of converting lipoteichoic acid (LTA) to deacylated lipoteichoic acid (dLTA). The enzyme(s) appear to be located mainly in the membrane, although activity was also found in the cytoplasm. Determination of the sites of cleavage within the LTA molecule was approached by comparing the chemical composition of LTA and native dLTA. Native dLTA, as distinguished from chemically deacylated LTA, was isolated from buffer in which live streptococci had been resuspended and incubated. The chemical data suggest that the enzyme(s) was(were) lipolytic in nature; that is, the conversion of LTA to dLTA was the result of cleavage of the ester linkages between the fatty acids and the remainder of the LTA molecule.


Concentrations of phenobarbital, flurazepam, and flurazepam metabolites in autopsy cases. In five cases of death resulting from acute intoxication with phenobarbital and flurazepam, the blood, urine, brain, lung, liver,  and kidney levels of these drugs as well as the levels of N-1 hydroxyethyl, N-1 desalkyl, and N-1 desalkyl-3-hydroxy flurazepam metabolites were determined. Concentration of flurazepam and its metabolites was determined by using new gas chromatographic conditions employing a selective detector for nitrogen-containing substances and a column of 1% SP-1000. In addition, the EMIT technique was also employed on blood and urine samples and the results compared with GLC data.


Recurrent mutation and selection for increased penicillin titre in Aspergillus nidulans. Recurrent mutation and selection has been used to increase penicillin titre in two closely related strains of Aspergillus nidulans. A selection programme was initiated from each of the two strains (programmes A and B) and continued through six cycles of mutation and selection. Near-ultraviolet light in conjuction with 8-methoxypsoralen was employed as the sole mutagen throughout programme A and ethyl methanesulphonate as the sole mutagen throughout programme B. Excluding the first cycle of A, where only 50 strains were assayed, the selection programmes were identical. In each programme, 100 survivors were assayed for penicillin titre after each mutagenic treatment and, on the basis of a single yield test, the best five strains were picked and carried forward to the next cycle. In both selection programmes, a near 300% increase in penicillin titre was achieved. This yield advance illustrates the effectiveness for strain development of experimental designs involving successive cycles of mutagenesis with a single-stage screen and the selection of the top few percent survivors in each cycle.


Mapping of a new hem gene in Escherichia coli K12. A new type of haem-deficient mutant was isolated in Escherichia coli K12 by neomycin selection. The mutant, designated SASX38, accumulated uroporphyrin, coproporphyrin and protoporphyrin. Since it possessed normal ferrochelatase activity, it was assumed to be deficient in protoporphyrinogen oxidase activity. The gene affected in the mutant was designated hemG. Mapping of the hemG gene by phage P1-mediated transduction showed that it was located very close to the chlB gene (frequency of cotransduction 78.7%), between the metE and rha markers. This location is distinct from the other known hem loci in E. coli K12.


Microbial determinations by flow cytometry. Recent improvements in the optics and electronics of flow cytometry systems, as well as in staining techniques, permit the assay of such minute cellular constituents as the DNA and protein contents of micro-organisms. To assess the usefulness of this technique, DNA and protein content distributions were determined in Escherichia coli, Lactobacillus brevis, Lactobacillus casei, Chlorella kessleri 8k, Saccharomyces cerevisiae, Candida utilis, Schizosaccharomyces pombe and Euglena gracilis. Investigations of the DNA content distributions of polyploid strains of Saccharomyces cerevisiae indicated that the method can be used to determine ploidy. The rapidity of flow cytometry measurements allows accurate determinations in large populations.


Specific proline accumulation in an acrA mutant of Escherichia coli K12 grown in salt-hypertonic medium. Free proline is specifically accumulated in an acrA mutant of Escherichia coli K12 when cultured in a medium containing excess NaCl.


Specific heavy metal labeling of the 3-'terminus of phosphorothioate modified yeast tRNAPhe. Yeast tRNAPhe containing a phosphorothioate modified -CS-CS-A terminus binds two moles of chloroterpyridineplatinum(II). This result was determined by titrating the tRNA with [3H](terpy)PtCl] Cl, removing excess platinum by cation exchange chromatography, and determining the amount of bound platinum by radiocounting techniques. It has thus been established that adjacent phosphorothioate modified nucleotides can be labeled with an electron dense stain, a necessary requirement for electronmicroscopic sequencing of polynucleotides to become practical.


Creutzfeldt-Jakob disease treated with amantadine. A case of Creutzfeldt-Jakob disease treated with amantadine showed considerable initial improvement, followed by a period of almost five years during which the patient remained in a relatively stable condition until he died accidentally. The diagnosis was confirmed histologically.


Some neurological observations on Leonardo da Vinci's handwriting. The present study concerns neuropsychological aspects of the handwriting of Leonardo da Vinci. The evidence for Leonardo's left handedness is considered, and a critical appraisal of his mirror writing and its underlying mechanism is presented. The relationship between Leonardo's sinistrality, mirror writing and certain aspects of localisation of cerebral function are discussed. From these considerations and from new evidence obtained from contemporary historical sources, it is proposed that Leonardo's language skills were lateralised to the more unusual right hemisphere.


Familial Creutzfeldt-Jakob disease.

Familial Creutzfeldt-Jakob disease. A Finnish family is described with 9 cases of presenile dementia in 3 generations. The mean age at onset was 52 years (range 46--62 years). Progressive dementia, upper motor neuron signs, muscular rigidity, and twitching, irregular tremors were consistent features in the 6 clinically investigated patients and were associated with spongiform change in the cerebral cortex of one autopsy and two brain biopsy cases. The EEG showed progressive slowing without the occurrence of repetitive high-voltage complexes at any stage of the disease. The average duration of the disease (21 months, range 11--36 months) was longer than in the sporadic form of CJD. The occurrence of CJD within this family follows a pattern consistent with an autosomal dominant mode of inheritance, suggesting the possibility of vertical transmission of the presumptive causative agent for example by genomic integration or transplacental passage. However, the occurrence of the disease only through the paternal line of relationships and the presence of a discordant twin pair argue strongly against transplacental passage or transmission via mother's milk. Simple contact infection also seems unlikely, as conjugal cases were not found among the 7 married patients. The interval between the death of the last affected member in generation IV and the time of onset of the disease in the first affected member of generation V was 10 years. Thus setting a minimum incubation period if case-to-case transmission were occurring. To evaluate the role of a genetically determined susceptibility to infection studies on the HLA antigens and other genetic markers are in progress.


Kuru plaques in the brain of two cases with Creutzfeldt-Jakob disease. A common origin for the two diseases? We present two patients aged 66 and 69, with a rapidly progressive disease (10 and 15 months' duration) in which the presenting symptom was instability of gait. Later dementia was also a prominent feature. One case had myoclonus. Repeated EEGs showed symmetrical slowing in one case and periodic generalised bursts of triphasic waves at 1 cps superimposed upon a slow (3-4 cps) background activity in the other. The pathological findings consisted of classical Creutzfeld-Jakob disease (CJD), Kuru plaques (KP) were disseminated in the brain, but were more numerous in the cerebellum, putamen and thalamus. Neurons with large vacuoles in the cytoplasm were numerous in the putamen, thalamus and anterior horns. Stress is laid upon the common findings in both CJD and Kuru (K) (clinical features, pathological data, lack of antibody response, transmissibility, change in pattern on transmission). The possibility of a common origin of the two diseases is discussed.


A search for antibodies against glial cells in the serum and cerebrospinal fluid of patients with multiple sclerosis and Guillain-Barré syndrome. We have used indirect immunofluorescence to examine the binding of immunoglobulin in sera from patients with multiple sclerosis, Guillain-Barré syndrome, other neurological diseases, and normal subjects to marker-identified glial cells in dissociated primary cell cultures of neonatal rat corpus callosum and sciatic nerve. In corpus callosum cultures all the sera tested showed weak surface staining of oligodendrocytes and of a small percentage of astrocytes and bright staining of fibroblasts. The cerebrospinal fluid from one patient with multiple sclerosis showed the same pattern of staining while the cerebrospinal fluid from other patients with multiple sclerosis and pathological controls only showed weak staining of fibroblasts. None of the sera stained the cytoplasm of oligodendrocytes in frozen sections of adult rat optic nerve. In sciatic nerve cultures all sera showed weak staining of Schwann cells and fibroblasts. Thus we were unable to distinguish patients with demyelinating diseases from normal individuals or from patients with other neurological diseases in terms of serum or cerebrospinal fluid anti-glial cell antibodies.


Rate of regeneration of sensory axons in transected rat sciatic nerve repaired with epineurial sutures. Rat sciatic nerves were cut and the ends were rejoined using epineurial sutures. The most rapidly regenerating sensory axons, as measured by the pinch test, grew at a rate of 3.2 +/- 0.2 (SE) mm/day after a delay of 4.0 +/- 0.3 (SE) days. Regenerating axons began to grow beyond the site of injury about 2 days later in sutured nerves than in crushed nerves; this difference provides an estimate of the scar delay in sutured nerves. The rate of axonal outgrowth was slower in sutured nerves than in crushed nerves throughout the distal stump.


An improved method for the concentration of cerebrospinal fluid cells by suction tip and sedimentation chamber. To concentrate cells from cerebrospinal fluid, a new method was developed. The technique is a modification of the cell sedimentation method of Sayk. The fluid is absorbed after passing through a Nuclepore filter, pore size 0.4 micron. With the aid of simple utensils it is possible to obtain a cell preparation of high quality using only 0.3 ml of cerebrospinal fluid. The cytomorphology is as good as that achieved by Sayk's sedimentation technique. The cell yield was determined using an accurate and precise method to estimate the number of cells present in the cerebrospinal fluid. The average cell yield is 90%, and all staining methods are applicable. The system is easily modified, and can be suited to many other fluids and purposes.


Surface ultrastructure of the tegument of Clonorchis sinensis newly excysted juveniles and adult worms. The tegumental structures of newly excysted juveniles and adult worms of Clonorchis sinensis were studied using scanning and transmission electron microscopy. After excystation the juvenile's tegumental surface is characterized by knoblike protuberances and is armed almost entirely with numerous rows of small spines encircling the body. These spines are double- or triple-pointed on the anterior portion of the body and become single-pointed posteriorly. Four types of presumed sensory structures were observed as follow: A) ciliated knoblike papillae and B) nonciliated platelike papillae, both of which are arranged in rougly a bilaterally symmetrical pattern dorsally, ventrally, and laterally; C) rounded swellings of nonciliated papillae on the lips of the ventral and oral suckers, which are characterized in the transmission electron microscope by a rounded dense body in the apical bulb; and D) a sensory receptor with a bulbous projection having the appearance of a modified cilium, which was not found with SEM likely owing to its being enclosed by an extension of the tegument. In full-grown adult worms, the tegumental surface is knobbed or lobulated in various forms without surface spines. The tegumental structures in the adults appear to be clearly differentiated from those in the juveniles. Upraised, buttonlike papillae, each topped by a short cilium, which are similar to the Type A papillae in the juveniles, are distributed thickly around the oral and ventral suckers, and are rather randomly scattered over the remainder of the body. Some nonciliated swollen papillae were found on the lip of the ventral sucker.


Use of immunologic techniques to detect chemotherapeutic success in infections with Fasciola hepatica. II. The enzyme linked immunosorbent assay in infected rats and rabbits. An enzyme-linked immunosorbent assay (ELISA) was developed using microtiter plates for the immunodiagnosis of fascioliasis in rats and rabbits using extracts of adult worms partially purified by gel filtration chromatography using Sephacryl S-200. Partial purification was necessary to eliminate cross-reactivity with antisera having antibodies to schistosomes. Soft polyvinyl plates clearly gave superior results over hard polystyrine plates. Titers rose by 4 weeks of infection in rats with fascioliasis, by 6 weeks in the case of rabbits, and remained high through at least 12 and 28 weeks, respectively. Titers drop rapidly when animals are successfully treated with a fasciolicidal drug at 4--6 weeks of infection. The results show that the ELISA can be employed for the serodiagnosis of fascioliasis in rats and rabbits and is useful for the prediction of chemotherapeutic success.


Renal homotransplantation in children.

Renal homotransplantation in children. Ninety-six renal transplants in 77 pediatric patients are reported with follow-up as long as 12 1/2 years. Thirteen of the first 14 patients are living with a functioning kidney after eight to 12 1/2 years. The patient survival for the entire group is 78%. Sixty-four percent are living with a functioning transplanted kidney. Splenectomy was initially performed at the time of transplant but has been discontinued because of concern that splenectomy in the immunosuppressed patient was related to an increased occurrence of septic complications. Anencephalic newborn infants have been found to be a satisfactory source of cadaver donor kidneys. Growth and development have been satisfactory when the transplant is performed prior to 12 years of age, if it functions well, and if an alternate-day regimen of steroid administration is followed. Both boys and girls have now passed through puberty with their transplanted kidneys, have married, become parents, and are leading essentially normal lives. A plea is made for earlier transplantation in small children with irreversible progressive renal failure before they develop severe stunting of growth and before the need for prolonged dialysis.


Disposition of valproic acid in the rat: dose-dependent metabolism, distribution, enterohepatic recirculation and choleretic effect. A specific gas chromatographic assay has been developed for measurement of valproic acid (VPA) and its major conjugated metabolites. In rats given single intravenous doses, the decline in blood concentration of VPA was dose-dependent and followed first-order kinetics only at the lowest dose. The time required for the maximum concentration of VPA, after completion of the brief distribution phase, to decline by 50% was 11.7, 41 and 125 min at doses of 15, 150 and 600 mg of NaVPA per kg, respectively. A secondary increase in drug concentration, abolished by exteriorization of the bile, was observed in all intact rats with all doses. Some 45 to 55% of the dose appeared in the bile in 5 hr as VPA glucuronide. Urinary excretion of VPA glucuronide in intact animals accounted for 23 and 51% of the 15 and 150 mg/kg doses, respectively. Tissue distribution studies in rats sacrificed 20 and 90 min after dosage with [14C] NaVPA (150 mg/kg) showed that the drug concentration was highest in blood, moderate in liver, kidney, heart and lung and low in brain, fat, testis and skeletal muscle. During this interval the drug concentration declined in all tissues, whereas the total conjugated metabolites in the small intestine increased from 7 to 28% of the administered dose. The large intestine contained 30 times as much free drug as conjugate. Reabsorption of free VPA, released by hydrolysis of conjugate in the large bowel, accounted for the secondary rise in concentration of VPA observed in blood after single doses. The major urinary metabolites, VPA-glucuronide and 2-n-propylgutaric acid, were identified by gas chromatography/chemical ionization mass spectrometry. Sodium VPA caused a dose-dependent stimulation of bile flow, the magnitude and duration of which closely followed the blood concentration of VPA.


Peripheral electrosense physiology: a review of recent findings. Advances, since 1974, in understanding the physiology of electroreceptors are reviewed. In brief: 1. In fish that produce a weak electric discharge with electric organs, the tuberous electroreceptors are generally most sensitive to stimulus frequencies near the species', individual's, and even local, waveform of the electric organ discharge; there is a good match between receptor sensitivity and the normal stimulus. 2. The ability of tuberous electroreceptors to detect field distortions produced by reasonably sized objects is limited; an object must be closer than a body-length to be detected, and the afferent response is a negative power function of object distance. 3. The second major electroreceptor class, the ampullary electroreceptors, is sensitive to low frequency, low intensity electric fields, and this acute sensitivity results in the ability of the receptors in marine species to detect magnetic fields on the order of the Earth's. 4. The calcium ion is essential for normal functioning of ampullary electroreceptors.


Central nervous system physiology of electroreception, a review. There are several reasons why one can expect that the study of electric fish may prove instructive about general mechanisms of sensory processing and neuronal integration. These reasons include the following: the simplicity of the electrical signals which are the normal input and output; the availability of a variety of stereotyped behaviors to characterize the system as a whole; the case with which individual receptors or primary afferents can be activated; the demonstrated presence of corollary discharge and reafference mechanisms for motor control over sensory input; the presence of highly specialized CNS structures which have evolved to meet the unusual demands of the electrosensory system. Work relating to these and other aspects of the electrosensory systems is discussed with an emphasis on the potential which these systems offer.


Penetrating keratoplasty in children.

Penetrating keratoplasty in children. Sixteen penetrating keratoplasties were performed in 14 patients less than 16 years old. Clear corneas were obtained in 62.5% of eyes with significantly improved vision in 56.2% of cases. The problems of postoperative treatments, complications, and amblyopia were found to be manageable. The visual benefits of corneal transplantation in selected cases in children appear to outweigh the difficulties and problems engendered by this procedure.


The gingival response to well-finished composite resin restorations. Within the limits of this study, the following conclusions are made: 1. Well-finished and contoured composite resin restorations do not adversely affect the health of the gingiva. 2. The gingiva exhibits less inflammatory response to a well-finished and contoured composite resin restoration than to an open carious lesion. 3. The gingival inflammatory changes which do occur are independent of the presence of well-finished and contoured composite resin restorations. 4. Observation over an extended period of time is necessary to determine if composite resin restorations ultimately become gingival irritants.


Post and core fabrication beneath an existing crown. A technique has been described for constructing a post and core for a tooth fractured prior to insertion of a fixed partial denture. In selected patients, this method of repair offers an acceptable alternative to a more costly and time-consuming refabrication of a fixed prosthesis.


Stabilized occlusion rims for small interarch spaces. This article describes three methods for fabricating stabilized occlusion rims for close interarch spaces. To utilize these methods, the dentist must anticipate the lack of space and request that the rims be fabricated by one of the methods outlined prior to the maxillomandibular relations appointment.


A method of correcting the posterior palatal seal area of a maxillary complete denture. A processing technique for correcting the posterior palatal seal area of a maxillary denture has been described. The proper extension and displacement necessary for peripheral seal is reestablished without creating changes in occlusion or esthetics. Since the technique involves heat processing, the same acrylic resin present in the original base may be used, which makes the correction virtually impossible to detect.


Mode of action of delta-9-tetrahydrocannabinol on hypothalamo-pituitary function in adult female rats. Administration of delta-9-tetrahydrocannabinol (delta 9-THC) to pro-oestrous rats (5 mg/kg and 10 mg/kg, i.p. for 10 days) decreased the hypothalamic LH-RH content. Serum prolactin levels were reduced but serum LH and FSH and pituitary hormone content were similar to values in dioestrous rats. It is suggested that delta 9-THC acts primarily on the hypothalamus.


Plasma concentrations of FSH and LH in entire and castrated prepubertal bull calves treated with Gn-RH. In bulls there was no increase in plasma FSH and only a small increase in LH over the first 14 weeks of age. In steers (castrated) plasma LH and FSH were unchanged for the first 3 weeks but increased significantly at 7 and 14 weeks. After 100 micrograms Gn-RH, LH release in bulls was minimal until 7 and 14 weeks and there was no comparable rise for FSH. LH and FSH responded to Gn-RH throughout the trial in the steers. The neonatal calf testes selectively inhibited the release of FSH from the pituitary even when challenged with Gn-RH.


Pregnancy blockage and the memory of the stud male in the vole (Microtus agrestis). When female voles were allowed contact with the stud male for only 1 h at the time of mating, 55% exhibited pregnancy failure when exposed to a strange male 48 h later. When females were made psuedopregnant by hormone treatment and vaginal stimulation (i.e. no stud male involved), 87% exhibited luteal failure when exposed to a strange male. It is suggested that the characteristics of the stud male are rapidly imprinted upon the female at the time of mating and that this imprinting is important in preventing the female showing a blocking response to this male upon any subsequent exposure.


Evidence for a coitally induced 'mnemonic' involved in luteal function in the vole (Microtus agrestis). The development of luteal function in the vole is dependent on a neuroendocrine reflex which is initially activated by mating. Bromocriptine was used to destroy the CL initially induced by mating and fresh CL were induced by hormone treatment. The fate of such newly formed CL suggested that the luteotrophic effect of mating continued for about 10 days after mating, despite the destruction of the original mating-induced CL. The luteotrophic effect of mating therefore seems to be 'remembered'. A study of the fate of hormonally induced CL in females in which pregnancy had been blocked by exposure to a strange male suggested that the strange male may cause pregnancy failure by inhibiting or suppressing the luteotrophic 'mnemonic' activated by the stud mating.


Pituitary uptake of 125I-D-Leu6, Des-Gly N2(10) LH-RH-ethylamide in ovariectomized rats pretreated with oestradiol-17 beta. The objective of this study was to determine if pretreatment of ovariectomized rats with oestradiol-17 beta affects the anterior pituitary uptake of 125I-D-Leu6, Des-Gly NH2(10)-LH-RH-ethylamide (125I-D-Leu6-LH-RH). Oestradiol-17 beta (0.5 microgram/0.5 ml oil) or oil was administered to ovariectomized rats at 2, 4, 8, 12, 16, 20 or 24 h before death, and at 30 min before death, 5 ng 125I-D-Leu6-LH-RH were injected intravenously. The serum LH response to analogue administration in oil-treated rats did not change over time, but that in oestradiol-treated rats was depressed for 4 h and restored 8-24 h after oestradiol treatment, with the greatest response being at 16 h. However, the pituitary (adrenal, CNS cortex and thyroid) uptake of 125I-D-Leu6-LH-RH in oestradiol-treated and control rats did not change over the 24-h time period. These data suggest that oestradiol-17 beta does not affect pituitary responsiveness to 125I-D-Leu6-LH-RH by inhibiting or facilitating the uptake of this analogue by the anterior pituitary.


A simple method for removing the luminal epithelium of the mouse uterus for biochemical studies. The luminal epithelium of the mouse uterus was removed simply and rapidly by opening the uterine horns longitudinally and 'vortexing' them in buffer with glass balls. This procedure, which requires no specialized apparatus, was developed for use with uteri in different hormonal states, and 2 uterine horns/tube, 5 glass balls and vortexing for 2 min are suggested for routine use. Under these conditions, 79--100% of the cells were removed, yielding epithelial fractions of 65--90% purity. The suspension of cell constituents recovered contained intact nuclei which could be further purified. Extensive histological examination demonstrated that the other uterine tissues were minimally damaged.


Delayed implantation in lactating bank voles, Clethrionomys glareolus. The time of blastocyst implantation in lactating and non-lactating female bank voles was studied. In primiparous females implantation started 4 days and 9-11 h after mating. A delayed implantation of at least 1 1/2 days was found in lactating, multiparous females when compared to non-lactating, multiparous and primiparous females.


In vivo inhibitors of Escherichia coli phenylalanyl-tRNA synthetase. N-Benzyl-D-amphetamine is a potent in vitro and in vivo inhibitor of phenylalanyl-tRNA synthetase of Escherichia coli. The concentration of this inhibitor necessary for the in vivo inhibition is approximately 100-fold greater than that necessary for inhibition of the purified enzyme. Treatment of rel+ strains of E. coli with the inhibitor results in a decreased percentage of tRNA Phe which is charged, guanosine tetraphosphate formation, cessation of RNA synthesis, and growth arrest. Evidence is presented which demonstrates that the primary and perhaps sole mode of action of N-benzyl-D-amphetamine is inhibition of phenylalanyl-tRNA synthetase.


The sex ratio in spina bifida.

The sex ratio in spina bifida. Published reports on the sex ratio of spina bifida have been reviewed. With one exception, there seems to be no evidence of variation in the sex ratio of spina bifida. In particular, unlike anencephaly, the sex ratio of spina bifida seems to be unrelated to the prevalence of the malformation: this (M/(M+F)) is of the order of 0.44 in respect of all spina bifida births (liveborn and stillborn). The sex ratio of spina bifida in Negroes does not seem to differ from that in whites (though the data on this point are not numerous). The exception noted above concerns spina bifida occurrring in twins: these cases are disproportionately often female. The point stands in need of explanation.


Production of a bacteriocine-like substance by group-A streptococci of M-type 4 and T-pattern 4. A unique and characteristic bacteriocine-like inhibitor elaborated by M-type 4, T-pattern 4, group-A streptococci was isolated and partially purified. This inhibitor was found to be produced optimally in Todd-Hewitt broth; after extraction and concentration, was shown to be protein in nature, and to have a m.w. of c. 8000. It was extremely heat stable and acid tolerant, but was quickly inactivated in alkaline conditions. It could be demonstrated in cell-bound form, but 99.5% was found in culture supernates. It was specifically adsorbed by viable sensitive cells, and its mode of action was bacteristatic.


Spore antigens in the classification of some clostridia. The spore antigens of Clostridium sporogenes, C. histolyticum, C. bifermentans and the butyric group were compared. By spore agglutination and fluorescent-antibody technique (FAT) the 69 strains of C. histolyticum were divided into two types: serum raised against type I (66 strains) reacted with all strains of this species but showed no cross reaction with any of the three types of C. sporogenes; serum raised against type II (three strains) did not react with strains of C. histolyticum type I but showed cross reaction with all the 66 strains of C. sporogenes type I. Thus, by antigenic analysis, spores of C. histolyticum type I were found to possess two components designated E and F; E was a type-specific component whilst F was shared by strains of type II. In addition, strains of C. histolyticum type II possessed a second component, G, which was shared by strains of C. sporogenes type I. There was no cross reaction between the precipitinogens of the spores of the two species. Five strains of C. bifermentans formed a homogeneous group as judged by spore agglutination, FAT and precipitation reactions. There was no cross reaction with any of the other proteolytic species studied. Five butyric strains also formed a homogeneous group. Two antigenic components were therefore assigned to the spore antigens of the two groups: J, for C. bifermentans and K, for the butyric strains.


Phagocytosis measured as inhibition of uridine uptake: a method that distinguishes between surface adherence and ingestion. Polymorphonuclear leucocytes selectively inhibited the incorporation of 14C-uridine by intracellular staphylococci. Within specified limits, the amount of radiolabel incorporated by extracellular staphylococci was related to bacterial concentration. The incorporation of labelled uridine can thus be exploited to assay the extent to which association between staphylococci and polymorphonuclear leucocytes reflects surface adherence as opposed to ingestion. A comparison of the new method with a conventional viable-count determination of leucocyte-associated bacteria shows it to be comparable in efficiency when non-immune serum is used as opsonin and superior when specific opsonin is used.


Biotyping of Escherichia coli.

Biotyping of Escherichia coli. We examined the results of tests with 22 substrates for their ability to discriminate a series of 917 strains of Escherichia coli collected from different sources. The tests with three of the substrates were discarded because of difficulties in performance or interpretation, and another nine substrates because they provided little discrimination. The tests used to obtain biotype profiles for strains were those for the fermentation of dulcitol, D-raffinose or sucrose or both, L-rhamnose and L-sorbose, the decarboxylation of L-lysine and L-ornithine, the hydrolysis of aesculin, motility, and prototrophy. Observations on several series of cultures from different sources showed that biotype characters were stable in vivo and after storage on non-selective medium. The biotype profiles obtained were as reliable as partial O serotyping for the routine subtyping of strains of E. coli isolated from the urine of patients with long-term urinary-tract infections and those from other sources in different patients. Biotyping and O serotyping used in conjuction offered a very fine degree of strain discrimination.


The ability of cholestyramine resin and other adsorbents to bind Escherichia coli enterotoxins. Several adsorbent materials were evaluated for their ability to bind Escherichia coli enterotoxins. Cholestyramine, a strong anion-exchange resin, bound the heat-labile and the heat-stable types of enterotoxin and reduced significantly their effects in some animal models. However, its efficacy in the treatment of diarrhoeic piglets appeared to be adversely affected by the presence of milk in the alimentary tract.


Active immunisation of mice against muscle damage mediated by Candida albicans. The effect of active immunisation on muscle damage after systemic infection with Candida albicans was examined in a murine model. Mice were successfully immunised against acute muscle damage by vaccines of viable, nonviable, or disrupted C. albicans. In addition, markedly enhanced survival of immunised mice was demonstrated over a 4-week interval. There was protection against muscle damage in immunised mice without a reduction in the number of organisms present in cardiac tissue. The data indirectly implicate the role of humoral immunity in the protection afforded by immunisation.


Experimental infection of calves, piglets and lambs with mixtures of invasive and enteropathogenic strains of Escherichia coli. Mixtures of mutant organisms of an invasive (IN) strain, a strain enteropathogenic (EP) for calves, lambs and piglets, and a non-pathogenic (NP) strain of Escherichia coli, that could be differentiated from each other by their antibiotic resistances, were given orally to an immunoglobulin-negative (IG-) and an immunoglobulin-positive (IG+) calf, lamb and piglet. By the use of appropriate antibiotic-containing culture media, the concentrations of organisms of each of the three strains in the contents of the alimentary tracts and tissues (liver, spleen, kidney, blood and mesenteric lymph glands) of the animals were estimated when they were killed. In the three IG- animals, the IN strain proliferated in the tissues and the EP strain proliferated in the small intestines; in general, the concentrations of the IN strain in the small intestines and the EP strain in the tissues, apart from the mesenteric lymph glands, were as low as those of the NP strain in these sites. The only strain that proliferated in the small intestine of the IG+ animals was the EP strain, which proliferated in the small intestine of the calf and piglet; no organisms of either strain were isolated from the tissues of these three animals, except from their mesenteric lymph glands.


Treatment of self-injurious behaviour with a GABA (gamma-aminobutyric acid) analogue. Self-injurious behaviour (SIB) is not uncommon in the severely subnormal. Corbett (1975) found the incidence in several reported series to vary between 3.5 per cent and almost 40 per cent, and Van Velzen (1973), in a survey of ten institutions in the Netherlands, found it present in 584 patients out of almost 2,000 (30.3 per cent). Treatment is notoriously difficult and many kinds have been tried including physical restraint, drug regimes, and electric shock aversion therapy. An account is given here of a drug trial using baclofen, a gamma-aminobutyric acid (GABA) analogue that crosses the blood brain barrier. GABA, in addition to being a muscle relaxant, is also a major inhibitor in many areas of the brain, including the cortex and basal ganglia (Callingham, 1972) andit was presumed by the author that some severely subnormal defectives have damage in these areas and hence might be deficient in this inhibitor. The trial commenced with a preliminary period during which the reactions of patients to the drug at different dose levels were observed. This was followed by a double-blind cross-over trial in patients who had already shown improvement.


Evolutionary diversification of structure and function in the family of intracellular calcium-binding proteins. The maximum parsimony method was used to reconstruct the genealogical history of the family of intracellular calcium-binding proteins represented by six major present-day lineages, three of which--calcium dependent modulator protein, heart and skeletal muscle troponin Cs, and alkali light chains of myosin--were found to share a closer kinship with one another than with the other lineages. Similarly, parvalbumins and regulatory light chains of myosin were depicted as more closely related, whereas the branch of intestinal calcium-binding protein proved to have the most distant separation. The computer-generated amino acid sequence for the common ancestor of these six lineages described a four domain protein in which each domain of approximately 40 amino acid residues had a mid-region. 12 residue segment that bound calcium and had properties most resembling those of the calcium dependent modulator protein. It could then be deduced that parvalbumins evolved by deletion of domain I, inactivation of calcium-binding properties in domain II, and acquisition of increased affinity for Ca++ and Mg++ in domains III and IV. Regulatory light chains of myosin lost the cation binding property from three domains, retaining it in I, whereas alkali light chains of myosin lost this ability from each of the four domains. In skeletal muscle troponin C all domains retained their calcium-binding activity; however, like parvalbumins, domains III and IV acquired high affinity properties. Cardiac troponin C lost its binding activity from domain I but otherwise resembled the skeletal muscle form. Finally, intestinal calcium-binding protein evolved by deletion of domains III and IV. Positive selection could be implicated in these evolutionary changes in that the rate of fixation of mutations substantially increased in the mid portions of those domains which were loosing calcium-binding activity. Likewise, when the cation binding sites were changing from low to high affinity, an accelerated rate of fixed mutations was observed. Once this new functional parameter was selected these regions showed a remarkable conservatism, as did those binding sites which were maintaining the lower affinity. Moreover even in sequence regions not directly involved in cation binding, the lineage of troponin C because very conservative over the past 300 million years, perhaps becuase of the necessity for maintaining specific interfaces in order for the molecule to interact with troponin I and T in a functional thin myofilament. A similar phenomenon was observed in domain II of the regulatory light chains of the myosin lineage suggesting a possible binding site with the heavy chain of myosin.


Immediate reconstruction of gunshot injuries to the face. In the past, severe traumatic injuries to the face resulting from shotgun injuries have been managed by primary wound healing followed by little or late reconstruction. This would involve a long period of convalescence by the patient, followed by years of living with his deformity. With recent demands to minimize the patient's suffering and disabilities and to lessen hospitalization costs, a method of immediate reconstruction of such crippling facial injuries using a partially de-epithelialized skin flap has been devised and successfully applied to the patient presented here.


Host transcription in bacteriophage P22-infected  Salmonella typhimurium. The kinetics of host RNA synthesis, as measured by pulse-label kinetics and RNA-DNA hybridization, is inhibited 10-fold shortly after infection with bacteriophage P22. This early inhibition lasts through the first 6 min of infection and affects not only RNA synthesis but several other energy-requiring cellular functions. In lysogenic infections, the rate of bacterial transcription rapidly recovers to the value of uninfected controls. In lytic infections, the rate of host transcription increases only to about 20 to 25% of the original level, indicating a second mechanism for the inhibition of RNA synthesis in the lytic response. The early inhibition is multiplicity dependent, bhloramphenicol insensitive, and independent of phage gene 24. The lytic inhibition is dependent upon the expression of gene 24 but independent of gene 23.