Pioneer in public health education: Roscoe Conkling Brown

In order to study the influence of ageing on the hormonal function of the endothelium in man, plasma endothelin levels were measured in 11 normal young persons (mean aged 25.7 +/- 1.8 years) and in 16 apparently healthy elderly subjects (mean 87.5 +/- 5.4 years) without anamnestic or clinical signs of symptomatic atherosclerosis. The mean plasma level +/- SD of endothelin was 2.72 +/- 0.61 pg/ml in elderly subjects and 2.09 +/- 0.66 in young subjects. The difference was statistically significant (p < 0.05). Various humoral or local age-related environmental factors may be responsible for this result. In particular increased vascular production of endothelin may be the response to endothelial cell damage caused by an asymptomatic atherosclerotic process. Studies still need to define whether enhanced plasma endothelin levels in elderly subjects not suffering from symptomatic atherosclerosis are the consequence of ageing alone or an ongoing but clinically silent atherosclerotic process.     

Neisserial porins inhibit human neutrophil actin polymerization, degranulation, opsonin receptor expression, and phagocytosis but prime the neutrophils to increase their oxidative burst

Porins are trimeric proteins that constitute water-filled pores that allow transmembrane diffusion of small solutes through the outer membrane layer of gram-negative bacteria. The porins are capable of inserting into the membranes of eucaryotic cells, and in the present study we have examined the in vitro effects on neutrophil functions of the following purified porins: meningococcal outer membrane protein classes 1 and 3 and gonococcal outer membrane protein 1B (P1B). The neisserial porins inhibited human neutrophil chemoattractant-induced actin polymerization and degranulation of both primary and secondary granules. The neutrophil expression of immunoglobulin G (IgG) Fc receptors II (Fc gamma RII; CDw32) and III (Fc gamma RIII; CD16), as well as the activation-dependent downregulation of Fc gamma RIII, were reduced by the meningococcal and gonococcal porins. The neisserial porins impaired the upregulation of complement receptors 1 (CD35) and 3 (CD11b) and inhibited the phagocytic capacity of neutrophils, as evaluated by the uptake of meningococci (strain 44/76) in the presence of patient serum containing known amounts of IgG against meningococcal porins. The porins also primed neutrophils to increase their intracellular hydrogen peroxide production in response to FMLP, whereas no such priming was observed if the neutrophil protein kinase C was stimulated directly with phorbol myristate acetate. The neisserial porins influenced neutrophil functions in a time- and concentration-dependent manner. The meningococcal class 1 outer membrane protein and the gonococcal P1B tended to alter neutrophil functions more than the meningococcal class 3 protein. Thus, the neisserial porins inhibited human neutrophil actin polymerization, degranulation, opsonin receptor expression, and phagocytosis but primed the neutrophils to increase their oxidative burst. It remains to be determined whether these in vitro observations reflect mechanisms that may be of importance for the interaction between neutrophils and Neisseria species in vivo.     

Effect of the sulfonylurea glyburide on glycogen synthesis in alloxan-induced diabetic rat hepatocytes

1. The effect of glyburide (glibenclamide) treatment on the liver glycogen levels of diabetic rats have been studied. 2. 3 weeks treatment with glyburide (5 mg/kg, orally) increased liver glycogen and decreased blood glucose levels. 3. The results of this study demonstrated that the sulfonylurea, glyburide is capable of exerting direct insulin-like effects on liver glycogen values in vivo.     

酒店热水与空调系统联合供应解决方案探讨

本文介绍酒店热水与空调系统联合供应的几个优化方案,涉及到太阳能和热泵技术的应用原理与系统,应用中充分考虑两者的结合,选择最优的方案,做到最大限度地节能。     

HIPS/EVOH高阻隔复合材料的加工工艺

本文介绍了高阻隔EVOH树脂的性能特点和应用情况。探讨了开发硬包装用EVOH复合材料的必要性。结合实际开发经验,介绍了HIPS/EVOH复合材料的成型设备和加工工艺,分析了影响复合材料性能的关键问题和解决方案。     

食品安全的现状分析

通过近几年对市场随机抽查的结果汇总分析,分析目前的食品安全状况、产生问题的主要原因和特点。提出尽快完善统一全面的食品安全标准、在食品生产企业中进一步推广建立食品安全管理体系、运用风险性分析框架管理食品安全,建立和完善的食品安全风险评估评价体系和建立食品安全信息监测、通报和发布的网络体系的建议。