Exposure to 1-bromopropane causes degeneration of noradrenergic axons in the rat brain

1-Bromopropane (1-BP) has been used as an alternative to ozone-depleting solvents. Previous studies showed that 1-BP is neurotoxic in animals and humans. In humans, exposure to 1-BP caused various neurological and neurobehavioral symptoms or signs including depressive or irritated mood. However, the neurobiological changes underlying the depressive symptoms induced by 1-BP remain to be determined. The depressive symptoms are thought to be associated with degeneration of axons containing noradrenaline and serotonin. Based on this hypothesis, the present study examined the effects of repeated exposure to 1-BP on serotonergic and noradrenergic axons. Exposure to 1-BP induced dose-dependent decreases in the density of noradrenergic axons in the rat prefrontal cortex, but no apparent change in the density of serotonergic axons. The results suggest that depressive symptoms in workers exposed to 1-BP are due, at least in part, to the degeneration of noradrenergic axons in the brain.     

Long-term follow-up of 111In-capromab pendetide (ProstaScint) scan as pretreatment assessment in patients who undergo salvage radiotherapy for rising prostate-specific antigen after radical prostatectomy for prostate cancer

PURPOSE: To evaluate the long-term failure patterns in patients who underwent an (111)In-capromab pendetide (ProstaScint) scan as part of their pretreatment assessment for a rising prostate-specific antigen (PSA) level after prostatectomy and subsequently received local radiotherapy (RT) to the prostate bed. METHODS: Fifty-eight patients were referred for evaluation of a rising PSA level after radical prostatectomy. All patients had negative findings for metastatic disease after abdominal/pelvis imaging with CT and isotope bone scans. All patients underwent a capromab pendetide scan, and the sites of uptake were noted. All patients were treated with local prostate bed RT (median dose 66.6 Gy). RESULTS: Of the 58 patients, 20 had biochemical failure (post-RT PSA level >0.2 ng/mL or a rise to greater than the nadir PSA), including 6 patients with positive uptake outside the bed (positive elsewhere). The 4-year biochemical relapse-free survival (bRFS) rates for patients with negative (53%), positive in the prostate bed alone (45%), or positive elsewhere (74%) scan findings did not differ significantly (p = 0.51). The positive predictive value of the capromab pendetide scan in detecting disease outside the bed was 27%. The capromab pendetide scan status had no effect on bRFS. Those with a pre-RT PSA level of <1 ng/mL had improved bRFS (p = 0.003). CONCLUSION: The capromab pendetide scan has a low positive predictive value in patients with positive elsewhere uptake and the 4-year bRFS was similar to that for those who did not exhibit positive elsewhere uptake. Therefore, patients with a postprostatectomy rising PSA level should considered for local RT on the basis of clinicopathologic factors.     

Pelvic examination training for interns: a randomized controlled trial.

PURPOSE: To evaluate the effectiveness of pelvic examination training for internal medicine interns conducted by instructors who also serve as models for the examination. METHOD: In 2001, 80 interns from three university internal medicine residencies completed questionnaires about their experiences with pelvic examinations. Interns who were available for training underwent baseline assessment of their pelvic examination skills and were randomized to training or to a control group that received only educational literature. Skills were assessed with a 29-item checklist at baseline and at follow-up by evaluators blinded to group assignment, and interrater agreement was estimated by review of audiotapes. RESULTS: Seventy-two interns were randomized and underwent baseline skills assessment. Seventy interns returned for follow-up assessment after approximately 14 weeks (range, 10-17 weeks). The 39 interns randomized to training and 33 randomized to the control group did not differ with respect to age, gender, or prior pelvic examination training. In both groups there was substantial variability in skills at baseline, with graduates of U.S. medical schools scoring significantly higher than did graduates of non-U.S. medical schools (0.66 versus 0.41, p < 10(-5)). Interns randomized to training had significantly higher scores at follow-up than did interns in the control group (0.79 versus 0.57, p < 10(-6)). For seven items verifiable by audiotape, interrater agreement was good (overall kappa, 0.54; range among items, 0.3-0.85). CONCLUSION: Specialized trainers can reliably evaluate and improve the pelvic examination skills of interns, and improvements are demonstrable three months after training. Further research is needed to ascertain whether training efficiency can be improved and to measure the impact of training on patient satisfaction and clinical outcomes.     

Retinal nerve fibre layer thickness measurements in normal Indian population by optical coherence tomography

PURPOSE: To obtain retinal nerve fibre layer thickness measurements by optical coherence tomography (OCT) in normal Indian population. MATERIALS AND METHODS: Total of 118 randomly selected eyes of 118 normal Indian subjects of both sex and various age groups underwent retinal nerve fiber layer thickness analysis by Stratus OCT 3000 V 4.0.1. The results were evaluated and compared to determine the normal retinal nerve fiber layer thickness measurements and its variations with sex and age. RESULTS: Mean +/- standard deviation retinal nerve fiber layer thickness for various quadrants of superior, inferior, nasal, temporal and along the entire circumference around the optic nerve head were 138.2 +/- 21.74, 129.1 +/- 25.67, 85.71 +/- 21, 66.38 +/- 17.37 and 104.8 +/- 38.81 microm, respectively. There was no significant difference in the measurements between males and females and no significant correlation with respect to age. CONCLUSION: Our results provide the normal retinal nerve fiber layer thickness measurements and its variations with age and sex in Indian population.