Cardiovascular Response to Acute Cold Stress in Non-Obese and Obese Healthy Adults

Background

Obesity is a global epidemic with important health care and financial implications. The cold pressor test (CPT) which is considered to be a sympathy-excitatory manoeuvre is a simple, noninvasive and validated test. The objective of this study was to assess and compare the cardiovascular response to cold pressor test in non-obese and obese healthy adults.

Methods

The study included 400 subjects, of which the study group included 200 adults who had body mass index (BMI) of more than 30 Kg/m,² and 200 non-obese adults were enrolled as controls with BMI less than 25 kg/m². The study was conducted for a period of two months. CPT was used to assess cardiac response to acute cold exposure in the present study. Baseline systolic and diastolic blood pressure recording was done using mercury sphygmomanometer during resting condition and following cold pressor test. The results were expressed as mean, standard deviation, and data were analyzed using ANOVA test. P < 0.05 was considered statistically significant.

Results

The mean change in systolic blood pressure before and after cold pressor test (CPT) was less in obese (7.12 ± 5.28) as compared to non-obese subjects (10.38 ±6.35). This was statistically significant which indicates impaired sympathetic function in otherwise healthy obese.

Conclusion

The study concluded that blood pressure response to cold pressor test was reduced in obese compared to non-obese subjects indicating reduced sympathetic activity in healthy obese adults.     

5-Fluoro-uracil and low molecular weight heparin in the management of proliferative vitreo-retinopathy

Background: Proliferative vitreo-retinopathy (PVR) is the most common cause of failed repair of a primary rhegmatogenous retinal detachment (RRD). The success rates for the surgery of complicated RRD has doubled with improved vitreous techniques from 35-40% to approximately 65-75% at six months. However, despite these advances, recurrent vitreo-retinal traction leads to re-detachment in more than one-fourths of the initially successful cases. The use of adjunctive treatments to prevent cellular proliferation holds promise for the prevention of PVR or recurrences after surgery. One focus has been on the use of intra-vitreal antimetabolites to prevent the occurrence of PVR.     

Decreased levels of p26-Bcl-2, but not p30 phosphorylated Bcl-2, precede TGFbeta1-induced apoptosis in colorectal adenoma cells

Bcl-2 expression is confined to the base of the colonic crypt, whereas transforming growth factor beta (TGFbeta) is expressed in the upper crypt, as are the apoptotic death promoters, Bak and Bax. In colonic adenoma cells, TGFbeta induces a growth arrest. In some adenoma cell lines, this is accompanied by apoptosis and in others it is not. In this study, we used two human colonic adenoma cell lines: RG/C2, in which TGFbeta induces a G1 arrest without apoptosis, and BH/C1, in which TGFbeta induces both a G1 arrest and apoptosis. TGFbeta does not induce apoptosis in RG/C2 cells even if hydrocortisone and insulin are removed from the culture medium. In BH/C1 cells, TGFbeta induces apoptosis in the presence of insulin and hydrocortisone. Apoptosis induced by TGFbeta is preceded by a reduction in p26-Bcl-2 protein levels. There was no change in the levels of the p30 phosphorylated form of Bcl-2 or in levels of the proapoptotic proteins Bax or Bak. RG/C2 cells did not show decreased Bcl-2 levels in response to TGFbeta- induced growth inhibition. Therefore, TGFbeta regulates Bcl-2 expression in colonic adenoma cells which undergo apoptosis in response to TGFbeta, but not in those which are growth inhibited, but resistant to TGFbeta-induced apoptosis. TGFbeta may play an important role in the colonic epithelium, not only in the inhibition of cell proliferation, but also in the regulation of apoptosis.      

DERMAL NEUROVASCULAR DYSFUNCTION IN TYPE 2 DIABETES

The present article summarizes recent observations obtained in our laboratory which clearly indicate that sex steroids exert relevant effects on the peripheral nervous system. In particular, the following important points have emerged: (1) Steroids exert stimulatory actions on the synthesis of the proteins proper of the peripheral myelin (e.g., glycoprotein Po and peripheral myelin protein 22) in vivo and on the Schwann cells in culture; (2) in many cases the actions of hormonal steroids are not due to their native molecular forms but rather to their metabolites (e.g., dihydroprogesterone and tetrahydroprogesterone in the case of progesterone; dihydrotestosterone and 5 alpha-androstane-3 alpha,17 beta -diol in the case of testosterone); (3) the mechanism of action of the various steroidal molecules may involve both classical (progesterone and androgen receptors) and nonclassical steroid receptors (GABA, receptor); and finally, (4) the stimulatory action of steroid hormones on the proteins of the peripheral myelin might have clinical significance in cases in which the rebuilding of myelin is needed (e.g., aging, peripheral injury, demyelinating diseases, and diabetic neuropathy).     

用电化学检测器的高效液相色谱法测定血清及尿中速尿的含量

本文报告了用电化学检测器的高效液相色谱法测定血清及尿中速尿含量的方法。样品予处理方法:血清用乙腈除蛋白,尿用蒸馏水稀释50倍。采用作者合成的FD-Val-OH作为内标物。色谱条件为:反相柱,以含35%乙醇的5mmol/L四丁基铵水溶液为流动相(pH7.50),流速1.0ml/min;用电化学检测器,检测电压0.90V:速尿及内标物的保留时间分别为10和15min。通过计算速尿对内标物的峰高比求得速尿含量。血清及尿中的最低检测浓度分别为16和9ng/ml。标准曲线在0.25～5ng/μl(血清)、0.5～10ng/μl(尿)的浓度范围内呈线性关系。血清及尿中回收率分别为100.5%和100.6%。变异系数在4.6%以下。