Role of dietary fatty acids and acute hyperglycemia in modulating cardiac cell death.

OBJECTIVE: We examined the effect of dietary manipulation of palmitic acid (20% [w/w] palm oil [PO]) on cardiomyocyte apoptosis in the rat heart under normoglycemic and hyperglycemic conditions in vivo. We used 20% (w/w) sunflower oil (SO; a diet rich in omega-6 polyunsaturated fatty acids) as an isocaloric control. METHODS: Adult male Wistar rats were fed experimental diets containing normal laboratory chow (5% corn oil) or a high fat diet (AIN-76A with PO or SO) for 4 wk. Subsequently, to induce diabetes, rats were injected with streptozotocin (55 mg/kg, intravenously). After 4 d of diabetes, hearts were tested for evidence of lipotoxicity and cell death, and the serum for its related markers. RESULTS: Feeding PO and SO magnified palmitic and linoleic acid contents within lipoproteins and hearts respectively. Compared with SO, PO diabetic hearts demonstrated significantly higher levels of apoptosis, with an altered Bax:Bcl-2 ratio, augmented lipid peroxidation, and protein modification by formation of nitrotyrosine. Interestingly, SO-fed diabetic animals demonstrated an increase in serum lactate dehydrogenase and myocardial necrotic changes. CONCLUSION: In marked contrast to results obtained in vitro, PO feeding led to only a minor fraction of cardiomyocytes undergoing apoptosis and suggests that, in the intact heart, protective mechanisms could be triggered that dampen excessive apoptosis. Of greater clinical significance was the observation that "heart-friendly" vegetable oils such as SO, rich in omega-6 polyunsaturated fatty acids, could precipitate cardiac necrosis, and questions its beneficial role in the cardiovascular system, especially following diabetes.

Functional assessment in the rat by ground reaction forces.

Although the rat sciatic nerve model is used extensively in the investigation of repair techniques, and a variety of evaluation methods utilized to assess the results, a means to measure directly and accurately the return of function in these animals is absent. Histologic, histomorphometric, and electrophysiologic methods can be reliable indicators of nerve regeneration but do not correlate to functional recovery. The purposes of this study were to develop apparatus to continuously measure ground reaction forces (GRF) and use GRF parameters in the assessment of gait parameters in normal rats preoperatively and following peripheral nerve severance and repair. Three neurorrhaphy methods: direct sciatic nerve repair, direct tibial nerve repair and double sciatic nerve repair simulating autograft, as well as a non-repaired tibial nerve transection were evaluated. The testing apparatus was designed to measure the spontaneous and voluntary effort of the rat with objective data. Three orthogonal components - vertical, craniocaudal (braking and propulsion), and mediolateral - of the ground reaction force were measured. Preoperative data showed that vertical forces were comparable among the four limbs but propulsion and braking forces displayed significant differences. At 12 weeks, functional recovery was most evident in the direct tibial nerve repair group and absent in the non-repaired tibial defect group. Direct sciatic nerve repairs and sciatic nerve grafts resulted in lesser degrees of improvement. Results indicated that the propulsive force is the optimal GRF parameter for evaluating recovery of useful function.

Sex differences in professional help seeking among adult black Americans.

This paper provides baseline data on sex differences in the use of professional help for serious personal problems in a nationally representative sample of adult black Americans. Bivariate analyses revealed that women had higher levels of psychological distress and were significantly more likely to seek professional help than were men. They were also more likely to utilize physicians and social service agencies. The relationship of gender to these help resources remained significant even when the effects of problem severity and differential problem definition were taken into account. Controlling for income, however, eliminated the sex difference for social services use but not for physician use.

Reactive synovitis after silicone arthroplasty.

A number of patients with silicone rubber implants performed by us and other surgeons initially had excellent results; however, they returned with swelling and discomfort. We studied 18 patients ranging in age from 16 years to 57 years who presented 8 to 78 months (average, 31.7 months) after silicone arthroplasty (four scaphoid, six lunate, one scapholunate, four finger, two wrist, one trapezium, and one ulnar head for metacarpal hemiarthroplasty). Erosive osteolysis was seen on x-ray films, with progressive destruction evident in patients followed serially. None of the patients' conditions responded to conservative care. The severity of the proliferative, inflammatory synovitis and the foreign material in the multinucleated giant cells correlated with the interval since arthroplasty. Implant surface analysis by scanning electron microscope and x-ray spectrometer showed that silicone microparticles were the result of implant degeneration and erosion. All joint cultures were negative. Silicone particulate synovitis and destruction were arrested by the removal of the implant, a synovectomy, and curettage of the lytic lesions at salvage (resection arthroplasty or arthrodesis). Patients who have had silicone arthroplasties should be followed indefinitely, at regular intervals, by x-ray films and clinical examination.

Absorbable versus nonabsorbable suture for microneurorrhaphy.

The results of epineural microneurorrhaphy with use of 10/0 monofilament absorbable (Vicryl and Dexon) and nonabsorbable ( Dermalon , Ethilon, and Prolene) microsuture were compared in 150 isogeneic male Sprague-Dawley rats. After sciatic nerve transection and epineural repair, the animals were observed clinically and reexplored before death at intervals from 2 days to 20 weeks. Half of the animals were randomly selected for electrodiagnostic studies at 6, 12, and 20 weeks before sacrificed. We found no significant clinical, electrodiagnostic, or histologic differences affecting axonal regeneration that were attributable to any of the suture types used. All sutures incited moderate zones of localized inflammation acutely. After dissolution, the absorbable group was essentially free of inflammation, whereas the nonabsorbable sutures persisted in small local granulomas. A possible advantage may be suggested in the use of monofilament absorbable sutures for microneural repairs in certain situations.

Black unwed adolescent fathers: a comparative study of their problems and help-seeking behavior.

THIS RESEARCH EXAMINES THE KINDS OF PROBLEMS THESE YOUNG FATHERS ARE LIKELY TO SEEK HELP FOR AND ADDRESSES ITSELF TO THE QUESTION: Is there a difference in the help-seeking behavior of unwed adolescent fathers who reside in different cities? Despite the complexity and diversity of their difficulties, it was clear from the analyses that the young fathers were likely to have emotional as well as concrete needs. Additionally, it was found that the unmarried adolescent fathers in this research were more similar than they were different in their help-seeking behavior.

Help-seeking behavior among select populations of black unmarried adolescent fathers: implications for human service agencies.

This study was undertaken to provide additional information on what are appropriate roles for agencies in relation to unmarried adolescent fathers. The findings indicate that such appropriate roles for agencies would include the provision of psychosocial counseling, vocational guidance, and parenting education. It was concluded that agency personnel would have to reach out assertively to unmarried adolescent fathers in order to serve them more effectively. (Am J Public Health 1981;71:733-735.)