Effect of configuration of muramyl dipeptide glycoside bond and structure of glycoside aglycon on their capacity to stimulate production of interleukin-1 and tumor necrosis factor by macrophages

Effects of 11 original glycoside derivatives of muramyl dipeptide on the production of interleukin-1 and tumor necrosis factor by mouse peritoneal macrophages were studied. The relationship between macrophage activation evaluated by induction of these cytokines and configuration of glycoside bond and aglycon structure of MDP was revealed.     

Solar heat load: heat balance during exercise in clothed subjects

Summary Six subjects exercised for 60 min on a cycle ergometer. Their backs were exposed to an artificial sun with a spectral distribution similar to sunlight and an intensity of 724 W m^–2. Each subject took part in four experiments in random order: wearing suits of polyester (insulation value = 0.5 clo), white (WP) or black (BP), or cotton (0.6 clo), white (WC) or black (BC). Measured by partitional calorimetry, the calculated heat losses and gains for the four conditions balanced within less than 10%. The differences between the short-wave radiation gains of subjects in white or black garments were small. This is due to the transparency of the white materials, which allows a larger percentage of the radiation to penetrate the clothing. The surface temperatures of the sun-exposed areas were very high, especially in the black suits. This promotes dry heat loss. Therefore the sweat loss in the black suits and the differences between the black and white clothes became relatively small. The physiological strain in steady-state exercise, as expressed by average heart rates, was 142 (WP), 154 (BP), 151 (WC), and 160 (BC) beats min^–1; the sweat losses were 649 (WP), 666 (BP), 704 (WC), and 808 (BC) g. For both of these measures values for white polyester were significantly less than those for black cotton.     

Cytokine regulation of Group II phospholipase A2 expression in glomerular mesangial cells

Phospholipase A₂ (PLA₂) is believed to play an essential role in inflammatory processes by releasing arachidonic acid from membrane phospholipids for synthesis of important lipid mediators, such as prostaglandins, leukotrienes and platelet activating factor.We have used glomerular mesangial cells as a model system to study the regulation of PLA₂ under inflammatory conditions. Potent pro-inflammatory cytokines, such as interleukin 1 (IL-1) and tumour necrosis factor (TNF), as well as agents that increase cellular cAMP levels have been found to increase Group II PLA₂ gene expression in a time- and dose-dependent manner.     

Tumor Necrosis Factor Gene Polymorphism in Chronic Sinusitis

Objectives It is likely that genetic factors play a role in the etiology of chronic sinusitis, and airway inflammation is an important pathological feature in chronic sinusitis. We hypothesized that individuals with greater inflammatory responses may be more likely to acquire the disease. Polymorphisms of the tumor necrosis factor (TNF) genes have been described, and certain inflammatory diseases are reportedly associated with certain alleles of TNF genes. The purpose of this study is to examine whether there is an association between some alleles of TNF genes and chronic sinusitis. Study Design Thirty‐eight Japanese patients with intractable chronic sinusitis were selected on the basis of the following criteria: 1) persistent mucous or mucopurulent nasal discharge and/or postnasal dripping for longer than 3 years and 2) opacification in bilateral maxillary sinuses and ethmoid cells on plain radiographic films. Methods Both tumor necrosis factor‐α (TNF‐α) and tumor necrosis factor‐β (TNF‐β) gene polymorphisms were analyzed by polymerase chain reaction (PCR) with restriction fragment length polymorphisms in these patients and 35 healthy control subjects. Results A significantly higher frequency (P < .05) of TNFB*2 allele of TNF‐β gene polymorphism was observed in patients with chronic sinusitis (74%) compared with control subjects (56%). There was no association between alleles of TNF‐α and chronic sinusitis. Conclusion We concluded that TNF‐β gene polymorphism may form a component of the genetic predisposition to chronic sinusitis in Japanese patients.     

Effect of superantigen on ion electrophysiology and permeability in rabbit maxillary sinus epithelia

Objective Superantigens are potent inflammatory stimuli which derive from pathogenic microbes such as bacteria, viruses and protozoa. The aim of this study was to investigate the role of superantigens on the function of rabbit maxillary sinus epithelium. Methods Twenty New Zealand white rabbits were divided into 4 groups. Rabbit sinus mucosa was separated under a surgical microscope and mounted in Ussing chambers to record short circuit current, conductance and permeability to horseradish peroxidase (HRP). Group A was used as normal control. Group B was stimulated with an injection of superantigen into the sinus for 4 hours. The sinus mucosa of Group C was stimulated by the addition of tumor necrosis factor α (TNF-α) into Ussing chambers. Group D sinus mucosa was stimulated by superantigen after pretreatment with anti-TNF-α antibody. Results Superantigen evoked increases in sinus epithelial cell baseline short circuit current, conductance and permeability to HRP stimulated by the addition of TNF-α into Ussing chambers. These were similar to results from superantigen stimulation in vivo. The effect of superantigen on sinus epithelial cells could be blocked by pretreatment with anti-TNF-α antibody. Conclusions Superantigen affected the function of sinus epithelial cells, including the capability of epithelial defensive barrier, which might be mediated by TNF-α.     

重度蒸汽吸入性损伤犬伤后肿瘤坏死因子水平的改变及其意义

目的研究蒸汽吸人性损伤犬伤后血浆肿瘤坏死因子水平的改变及其与吸入性损伤呼吸循环功能受损程度的关系.方法取犬15条,以蒸汽致重度吸入性损伤,分别于伤前、伤后1h、2h、3h、4h观察有呼气相气道阻力(RE)、心率(HR)、心输出量(CO)、动脉血氧分压(PaO2)、血浆TNF水平;伤后4h致死动物,取肺做病理检查.结果伤后1hTNF、RE升高,HR、CO、PaO2下降;TNF与RE正相关(r=O.965,P<O.01),与CO负相关(r=-0.824,P<O.05).结论严重蒸汽吸入性损伤激发TNF分泌,这是诱发肺损伤及循环系统甚至全身器官功能障碍的重要原因.     

双极人工股骨头置换术治疗高龄股骨颈骨折

目的 通过对６６例７０岁以上老年人股骨颈骨折临床分析,探讨其手术可行性、术式选择。方法 回顾分析患者的术前并存症、术前准备、术式选择、麻醉方式、术中情况、术后处理及随诊情况。结果 本组无术中死亡病例,平均住院２８天,平均随访２６个月。良好率６３．６％。结论 ７０岁以上老人股骨颈骨折行双极股骨头置换术治疗是可行的。     

临产时初产妇胎头浮动对分娩的影响

目的 了解临产时初产妇胎头浮动发生因素及对分娩的影响,探讨产时如何采取合理措施,有利分娩。方法 采用回顾性资料分析方法,对１９９９年１月至２０００年４月在我院分娩的临产时初产妇胎头浮动孕妇１５０例的临床资料进行分析。并与随机抽样同期分娩单胎头位初产妇临产时胎头入盆１７０例孕妇进行比较。结果 临产时初产妇胎头浮动的原因除可知因素外,另有许多病例未查出明显原因。其手术产率较入盆组明显升高。结论 临产时     

头高位倾斜时心血管反应的仿真

仿真头高位倾斜时心血管系统的反应,进一步研究有关立位应激的生理机制。方法以仿真下体负压时心血管反应的模型为基础,在血液重新分配子模中引入了重力致血液重新转移的环节,在压力反射控制子模型中考虑了心水平与颈动脉压力感受器间的流体静压差。