Winter weather versus group thermoregulation: what determines survival in hibernating mammals?

For socially hibernating mammals, the effectiveness of huddling as a means of energy conservation should increase with group size. However, group size has only been linked to increased survival in a few hibernating species, and the relative importance of social structure versus winter conditions during hibernation remains uncertain. We studied the influence of winter weather conditions, social group composition, age-structure, and other environmental factors and individual attributes on the overwinter survival of hoary marmots (Marmota caligata) in the Yukon Territory, Canada. Juvenile hoary marmot survival was negatively correlated with the mean winter (November to May) Pacific Decadal Oscillation (PDO) index. Survival in older age-classes was negatively correlated with PDO lagged by 1 year. Social group size and structure were weakly correlated with survival in comparison to PDO. The relationship between winter PDO and survival was most likely due to the importance of snowpack as insulation during hibernation. The apparent response of hoary marmots to changing winter conditions contrasted sharply with those of other marmot species and other mammalian alpine herbivores. In conclusion, the severity of winter weather may constrain the effectiveness of group thermoregulation in socially hibernating mammals.

Novel use of epidural catheter: Air injection for neuroprotection during radiofrequency ablation of spinal osteoid osteoma.

Osteoid osteoma (OO) is a benign bone tumor, with a male-female ratio of approximately 2:1 and mainly affecting long bones. Ten percent of the lesions occur in the spine, mostly within the posterior elements. Treatment options for OO include surgical excision and percutaneous imaging-guided radiofrequency ablation (RFA). Lesions within the spine have an inherent risk of thermal damage to the vital structure because of proximity to the neural elements. We report a novel use of the epidural catheter for air injection for the neuroprotection of nerves close to the OO of the spine. A 12-year-old and 30 kg male child with an OO of the L3 vertebra was taken up for RFA. His preoperative examinations were within normal limits. The OO was very close to the L3 nerve root. Under general anesthesia, lumbar epidural catheter was placed in the L3-L4 space under imaging guidance. Ten ml of aliquots of air was injected under imaging guidance to avoid injury to the neural structures due to RFA. The air created a gap between neural elements and the tumor and served as an insulating material thereby protecting the neural elements from damage due to the RFA. Postoperatively, the patient did not develop any neurological deficit.

Study of magnesium, glycosylated hemoglobin and lipid profile in diabetic retinopathy.

The present study was undertaken in 100 subjects, 30 diabetics without complication (group I), 40 diabetics with retinopathy (group II) and 30 non diabetic as normal control group (group III). Blood sugar levels, magnesium, cholesterol and triglyceride were analyzed from plasma and serum. The results were correlated with degree of diabetic control from the levels of glycosylated hemoglobin. Serum magnesium levels in group II were found to be significantly lowered than in group I. There was also significant difference in magnesium levels of group I and group III. We found a significant correlation between the glycosylated hemoglobin and magnesium levels in our study.The results also indicate that the patients with diabetic retinopathy showed significant rise in serum cholesterol and triglyceride. Probably hypomagnesemia and increased serum cholesterol and triglyceride levels are responsible for microvascular changes in diabetes leading to retinopathy. The purpose of this study was thus to gather information about the degree of control of diabetes and magnesium status.

Awareness, attitude and action about family planning in villages in Maharashtra.

PIP: A study undertaken in a randomly selected village with a population of 695, a majority of whom were agriculturalists or laborers living in huts or mud houses. All couples in the reproductive age group (125) were interviewed in their homes, husbands and wives separately. Couples belonged to Hindu, Muslim, and Scheduled Caste groups. Of the 250 respondents, 120 were literate. About 96% were aware that births could be prevented, with vasectomy and tubectomy the best known methods. Nearly all the respondents gave friends and relatives as the source of their information; family planning workers and posters were given as the source by less than 1/2. 86% of thoce aware of contraceptive methods found family planning acceptable, most expressing the idea that a small family was easier to raise. All of the 14% opposed to family planning were Muslims whose opposiition stemmed from their religious beliefs. 44 of the couples had adopted family planning -- 24 husbands having had vasectomies and 20 of the wives tubectomies. The reasons most often given for not accepting family planning were desire for more chidlren and fear of complications. Of the sterilized respondents, a large number of the men complained of side effects, and 5 of the women complained of excessive bleeding. All of those who expressed complaints said they would not recommend the operation. It is concluded that while awareness of family planning is at an acceptable level, the problem is to make family planning itself acceptable. 1 recommendation is that sterilized couples should receive special medical attention to make their experiences more positive.^ieng

Iodine induced thyrotoxicosis following povidine-iodine dressings: a case report.

A 40-year-old woman was admitted to the intensive care unit after a radical resection of a recurrent abdominal malignancy. Her postoperative course was complicated by sepsis requiring numerous abdominal operations with the abdomen being left open for drainage and dressings. Use of povidone-iodine soaked abdominal packs to reduce secondary infection led to development of thyrotoxicosis, which resolved following the cessation of the iodine dressings. A high index of suspicion is needed for the diagnosis of this condition in intensive care patients as the usual haemodynamic signs of thyrotoxicosis may be misinterpreted as being caused by sepsis.