It is well known that cadmium chloride administered as single, subcutaneous, sub-toxic doses selectively damages the rat testis, producing irreversible injury of the germinal epithelium and temporary damage to the interstitial tissue. Studies reported here demonstrate that: (1) this injury represents an ischemic necrosis secondary to rapid production of intertubular edema ( 4 to 6 hours), increased intratesticular pressure, with or without associated hemorrhage, and ultimate interference with testicular blood supply and drainage -not unlike injury following testicular artery ligation; ( 2 ) as dosage is progressively reduced to approximately one-sixth that employed by most investigators, interstitial tissue is unaffected and ischemic necrosis is supplanted by a non-necrotic degeneration of the germinal epithelium closely resembling, in its histopathology and irreparability, that occurring after vitamin E deficiency; (3) oral administration of vitamin E has no protective effect, and testes of rats critically depleted of E show no increased susceptibility to cadmium.Observations on the nature and distribution of tubular injury, and on the vasculature of the testis and epididymis, suggest that the unusual sensitivity of the testis to cadmium is related to unique features of its vasculature; namely, the pulseless, semistagnant flow of blood in the intratesticular course of the testicular artery, which permits cadmium to alter capillary endothelium permeability, causing edema and pressure effects leading to acute anoxia at higher levels of dosage, and diminishing degrees of anoxia with decreasing dosage levels. Comparable morphological features of the proximal segment of the caput epididymis make it likewise susceptible to cadmium injury.

We provide an overview of general competencies and specialty specific recommendations to serve as a foundation for medical schools to develop robust 4th-year curricula and for medical students to plan their 4th-year schedules.

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Percutaneous femoral artery closure devices are being used routinely after cardiac catheterizations. The use of these devices has been advocated to decrease length of stay, promote early ambulation, and prevent bleeding. We reviewed the use of these devices in our institution and report three cases of infectious complications (two pseudoaneurysms and one infected hematoma). Reports of infected pseudoaneurysms after cardiac catheterization before the implementation of these devices are rare. The use of these devices may be associated with an increased incidence of infected femoral pseudo-aneurysms.

Serum and tissue samples were obtained during surgery from four diabetics with neuropathy who underwent debridement or amputation for foot infections while receiving clindamycin 600 or 900 mg iv. Clindamycin concentrations were assayed by radioimmunoassay. Clindamycin was detected in all serum and tissue samples (range: 0.04-2.8 mg/kg in tissues and 1.1-11.1 mg/L in serum). In nine of the eleven tissue samples the clindamycin concentration exceeded the MICs reported for many pathogens commonly involved in such infections. In only a single instance was the ratio of tissue to serum concentration < 0.13.