植物凝集素(PHA)对小鼠白细胞及血清乳酸脱氢酶同工酶的影响

本文就 PHA 在不同时间内对小鼠白细胞及血清 LDH,同工酶的影响进行了观察,结果表明,PHA 对小鼠白细胞及血清的 LDH 酶活性有一定的影响,24h,48h,72h 三个不同时间组均与对照组有显著性差异(P<0.01),其中以48h 组酶活性最强,同时淋巴细胞的酶活性明显高于粒细胞;血清同工酶谱也有明显的变化,LDH_(1-4)均低于正常(P<0.01),LDH_5明显增高(P<0.01),同时出现了 LDH_5(?)亚带.     

The effect of 4-week streptozotocin-induced diabetes on responses to endothelin-1 in rat isolated atria

The effect of endothelin-1 has been examined on isolated spontaneously beating right atria and electrically driven left atria from diabetic rats and age-matched controls. Diabetes was induced by a single i.v. injection of streptozotocin (65 mg/kg) 4–5 weeks before the experiments. Endothelin-1 (0.01–100 nM) caused concentration-dependent increases in atrial rate and force; the increases were not different between atria from diabetic and control rats. The ability of endothelin-1 to reduce chronotropic and inotropic responses to noradrenaline was also not different between the two groups. Endothelin-1 (10 nM) decreased the chronotropic response to sympathetic nerve stimulation (2 Hz, 10 s) in atria from control rats by 68 ± 5% (n = 8), but this decrease was slightly smaller (45 ± 6%, N = 8) in atria from diabetic rats.

The results provide no evidence to suggest that the diabetic state markedly alters cardiac responses to endothelin-1.     

Anti-ultraviolet radiation effects of Coptis chinensis and Phellodendron amurense glycans by immunomodulating and inhibiting oxidative injury

HPLC analysis proved that Coptis chinensis glycan contained Ara, Man, and Gal. The monosaccharide constituents of Phellodendron amurense glycan were determined by HPLC analysis. HPLC analysis proved that P. amurense glycan contained Ara, Xyl, Glu, and Gal. FT-IR spectrum of C. chinensis glycan and P. amurense glycan showed the characteristic absorption peaks of carbohydrate polymers. Exposure of the human skin to ultraviolet radiation (UVR) leads to depletion of cutaneous antioxidants, regulation of gene expression and ultimately to the development of skin diseases. In the present study, free radical scavenging activity of C. chinensis and P. amurense glycan were evaluated. The photoprotective effect of C. chinensis and P. amurense glycan against UV-induced oxidative damage was also investigated in skin. At the concentration range employed, the two glycans showed strong free radical scavenging activity. Ultraviolet radiation reduced skin antioxidant enzyme and immunity activities in animals. Administration of C. chinensis and P. amurense glycans dose-dependently significantly increased skin antioxidant enzyme and immunity activities in animals. In conclusion, C. chinensis and P. amurense glycans present photoprotective properties, which can be attributed to molecules, such as flavonoids and carotenoids, which act as UV-absorbing molecules and as antioxidants, as well as stimulate immunity activities in animals.     

Evaluation of the Microcirculation in a Rabbit Hemorrhagic Shock Model Using Laser Doppler Imaging

The aim of this study is to evaluate the feasibility of Laser Doppler imaging (LDI) for noninvasive and dynamic assessment of hemorrhagic shock in a rabbit model. A rabbit model of hemorrhagic shock was generated and LDI of the microcirculation in the rabbit ears was performed before and at 0, 30, 60, and 90 min after hemorrhage. The CCD (Charge Coupled Device) image of the ears, the mean arterial pressure (MAP) and the heart rate (HR) were monitored. The mean LDI flux was calculated. The HR of rabbits was significantly (p < 0.05) elevated and the MAP was decreased after hemorrhage, compared to the pre-hemorrhage level. Within the initial 30 min after hemorrhage, the perfusion flux lineally dropped down. In contrast, the MAP values did not differ significantly between the time points of 0 and 30 after hemorrhage (p > 0.05). Both the flux numbers and the red-to-blue color changes on LDI imaging showed the reduction of the microcirculation. LDI imaging is a noninvasive and non-contact approach to evaluate the microcirculation and may offer benefits in the diagnosis and treatment of hemorrhage shock. Further studies are needed to confirm its effectiveness in clinical practice.     

Insights into IL‐29: Emerging role in inflammatory autoimmune diseases

Interleukin‐29 (IL‐29) is a newly discovered member of type III interferon. It mediates signal transduction via binding to its receptor complex and activates downstream signalling pathways, and therefore induces the generation of inflammatory components. Recent studies reported that expression of IL‐29 is dysregulated in inflammatory autoimmune diseases, such as rheumatoid arthritis, systemic lupus erythematosus, osteoarthritis, Sjögren's syndrome, psoriasis and systemic sclerosis. Furthermore, functional analysis revealed that IL‐29 may involve in the pathogenesis of the inflammatory autoimmune disorders. In this review, we will systematically review the current knowledge about IL‐29. The information collected revealed the regulatory role of IL‐29 and may give important implications for its potential in clinical treatment.     

Crystal structure of peptidoglycan recognition protein SA in Apis mellifera (Hymenoptera: Apidae)

Peptidoglycan recognition protein SA (PGRP‐SA) is a key pattern recognition receptor in the insect innate immune system. PGRP‐SA can bind to bacterial PGN and activate the Toll pathway, which triggers the expression and release of antimicrobial peptides to prevent bacterial infection. Here, we report the first structure of Apis mellifera PGRP‐SA from Hymenoptera at 1.86 Å resolution. The overall architecture of Am‐PGRP‐SA was similar to the Drosophila PGRP‐SA; however, the residues involved in PGN binding groove were not conserved, and the binding pocket was narrower. This structure gives insight into PGN binding characteristics in honeybees.     

急进高海拔时健康人夜间睡眠、呼吸状态和血氧饱和度的变化

在海拔2300m选择健康成年男性5人,急进抵海拔4660m,用多导监测仪分别在两地连续7h监测夜间睡眠、呼吸状态和血氧饱和度变化,进行自身对比。结果发现:(1)急进高海拔后,总睡眠时间、有效睡眠指数、Ⅲ～Ⅳ期深睡眠均较中度高原减少(p<0.01);总觉醒时间、Ⅰ～Ⅱ期浅睡眠高海拔较中度高原增多(p<0.05):(2)急进高海拔后,有3名健康人出现周期性呼吸,其中1名健康者出现周期性呼吸119次,伴有中枢性睡眠呼吸暂停,最低Sao_2为78％;(3)同海拔高度夜间睡眠时与清醒时Sao_2相比较,中度高原下降4.2％,高海拔下降11.2％(p<0.01);高海拔与中度高原夜间清醒时Sao_2相比较下降7.4％,睡眠时下降14.4％(p<0.001)。结果提示:(1)睡眠加重了高原人原有的低氧血症;(2)低氧血症导致睡眠结构的紊乱和睡眠质量的降低;(3)睡眠中出现的周期性呼吸,应视为机体的一种自我保护机制;(4)频发的周期性呼吸或睡眠呼吸暂停将影响大脑机能。