The response of the peroneal muscles to sudden inversion of the ankle during standing was investigated. The variation of the inversion angle with time was measured by means of a potentiometer attached to a specially designed test apparatus. During the tests, volunteers were subjected to sudden and unexpected inversion of their ankle, during which the surface EMG of the peroneal muscles was also recorded. Two groups were tested, one of normal subjects and one consisting of subjects with recurrent ankle sprains. There were 8 females and 3 males in each group. The subjects in the second group, who suffered from recurrent ankle sprains, had been asymptomatic during the last 2 months prior to the tests. For each subject in the two groups, both ankles were tested. The results indicated a latency time ranging from 60 to 80 ms for both groups. It was concluded that the reflex contraction of the peroneal muscles due to a sudden stretch inversion motion has no role in protecting the ankle joint during sprain and that this protection is mainly provided by the passive tissues.
Nonmelanoma skin cancer (NMSC) is the most common type of human cancer. Solar ultraviolet radiation (UVR) is the main causative factor in the development of NMSC. UVR plays a variety of roles in the induction of skin cancers. It can serve as a complete carcinogen or as a promoter of carcinogenesis. The typical UV-induced DNA damage is the generation of dimeric photoproducts between adjacent pyrimidine bases. Tumor suppressor gene p53 is a common target of UVR-induced mutations. There is a proliferative advantage of p53 mutant keratinocytes over normal keratinocytes that eventuates in neoplastic transformation. While UVB causes considerable DNA damage in the skin, UVA has only recently been shown to induce pyrimidine dimers and oxygen and nitrogen reactive species which damage DNA, proteins and lipids. The immunosuppressive effect of UVR contributes to its carcinogenic activity. Finally, any one of these effects of UVR may contribute to the induction of skin cancers by other agents such as X-rays, viruses, or chemical carcinogens. The mechanism by which UVR leads to cutaneous malignant melanoma is less clear and it may be a cofactor rather than an initiator of this tumor. Primary prevention of UVR exposure is the most effective means of reducing UVR carcinogenesis. Systemic retinoids may influence the appearance of new tumors in patient populations at increased risk of developing NMSC such as xeroderma pigmentosum and organ transplant recipients, but their efficacy is hindered by their side effects.
Milk quality data on a month-by-month basis from March 1999 to December 2000 were studied from five of the largest milk plants operating in New York State. The analyses focused on bulk tank somatic cell count (SCC), bacterial counts in the form of plate loop count (PLC), and antibiotic residue violations in the pool of milk of New York State, their mutual relation, and the influence of farm size. The average SCC was 363,000 cells/ml, the average PLC was 24,400 bacteria/ml, and the average number of antibiotic residue violations in the pool of milk was 3.9 per 1000 producers. Each month between 72 and 88% of the milk pool had SCC levels in compliance with the European Union (EU) requirements (SCC < 400,000 cells/ml). The findings in this study suggest that larger farms had lower SCC and PLC but more antibiotic violations. However, the larger farms contribute most to the SCC and PLC of the total pool of milk. Farms with high SCC also had higher PLC and more antibiotic violations. Measurable improvements in overall quality of the pool of milk in New York state would most likely occur by targeting incentives, education, and training programs for any farms with very high SCC and for larger farms with SCC between 400,000 and 750,000 cells/ml.
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