Inflammatory pain is also blunted by endogenous opioid peptides activating peripheral opioid receptors. Lesioning the amygdala causes blunted affect responses to both positive and negative stimuli. Sharp pointed toenails can be blunted by simply filing the point. They resemble a pair of scissors with the blade replaced by a blunted grip. Most tooth crowns had slightly blunted points, or were somewhat worn. Its first offensive failed disastrously as German Field Marshal Erwin Rommel blunted the thrust. The pharmacological effects of adenosine may be blunted in individuals taking large quantities of methylxanthines. The bilateral midbrain is also activated in individuals with schizophrenia diagnosed with blunted affect. The RAIR was shown to be absent or blunted. These fragments are blunted using endonuclease, and are ligated to produce hybrid genes. A blunted fourth metacarpal, with normal fifth metacarpal, can signify Turner syndrome. Shallow affect has equivalent meaning to blunted affect. This region is different in individuals with schizophrenia with blunted affect. The fourth and fifth metacarpal bones are commonly "blunted" or shortened, in pseudohypoparathyroidism and pseudopseudohypoparathyroidism. Their ability to recognize pain may be blunted by illness or the use of medication.