Comparison of the effects of prostaglandin E1 on platelet aggregation in normal and essential fatty acid deficient rats

The inhibition of the collagen-induced platelet aggregation by PGE₁ is considerably reduced in the plasma of EFA-deficient rats.     

Peritoneal macrophages from patients on continuous ambulatory peritoneal dialysis show a differential secretion of prostanoids and interleukin-1 beta.

In vitro secretion of the prostanoids PGE2 and PGI2 and of the cytokine IL-1 beta by peritoneal macrophages obtained from CAPD patients during episodes of peritonitis and infection free periods, was determined, after culturing with or without 5 micrograms/ml of LPS. The release of PGE2 and PGI2 as measured by its stable metabolite 6-keto-PGF alpha was determined in 10 episodes of peritonitis and 10 infection free periods. IL-1 beta release was determined in 14 episodes of peritonitis and 20 infection free periods. PGI2 release from macrophages declined sharply during peritonitis both in the absence and presence of LPS in the culture medium (p less than 0.005). A tendency to decreased PGE2 release was found during peritonitis, when macrophages were cultured in the absence of LPS. In the presence of LPS, the same amounts of PGE2 were released during peritonitis and during an infection free period. On the other hand, peritoneal macrophages released significantly more IL-1 beta during peritonitis as compared to an infection free period, provided that the cells were in vitro stimulated with LPS. In view of the interregulatory effects between prostanoids and macrophage cytokines in their production, these findings may indicate that the impaired release of PGI2 during peritonitis has allowed the macrophages to secrete more IL-1 beta after in vitro stimulation with LPS. This implies that PGI2 and PGE2 may play a distinct role in the regulation of cytokine secretion by these cells.     

苔藓-蓝藻共生体关系与固氮能力研究进展

苔藓-蓝藻共生体(BCS)能固氮, 是养分贫瘠地区森林氮输入的不可忽视的来源。BCS关系与固氮能力研究为科学认识生态系统氮输入与氮循环过程和机理提供了新的视角和有效途径, 具有重要的理论价值。然而, BCS关系、固氮作用与机理的研究迄今未受到足够关注, 报道较少, 认识仍然是零星而片段化的。基于系统查阅的相关文献, 该文综述了BCS的种类组成与共生关系类型、固氮能力及所固定氮的去向及其影响因素和作用机理, 指出了存在的问题及需要深入关注和亟待突破的4个研究方向。     

GABAB 受体变构剂药学研究进展

Y-氨基丁酸B受体(GABAB receptor,GABABR)是最具有药理学意义的药物靶点之一,具有复杂而精细的激活机制.传统的GABABR靶点药物开发集中于激动剂和拮抗剂,这类药物受到多种因素的制约,包括较强的副作用、药物代谢困难、机体耐药性明显等.变构剂结合于正构位点之外,能够调节GABABR异源二聚体亚基或结构域间的相互作用.正向变构剂(positive allosteric modulators,PAMs)和负向变构剂(negative allosteric modulators,NAMs)分别可以提高或降低GABABR的活性,并具有较高的特异性和药物安全性,同时还能够保持GABABR信号在时间和空间上的可控性.变构剂为GABABR靶点药物开发提供了新思路.     

胆道镜结合微爆破碎石治疗复杂性胆道结石

目的：探讨微爆破碎石用于治疗复杂胆道结石的治疗体会。方法：在胆道镜直视下,分别在术中和术后对158例复杂的胆道结石患者进行微爆破碎石,然后用取石网取出碎石,泥沙状结石随液体流出或让其自行流入肠道。结果：158例患者156例取石成功。取石成功率98.73%。明显提高了胆道取石的成功率。无1例出现胆道穿孔、瘘道穿孔及胆道出血等严重并发症。结论：在胆道镜下,采用微爆破碎石术治疗复杂的胆道结石是一种安全、可靠、高效的方法,可以明显提高结石的取净率。     

GABAB受体变构剂药学研究进展

Y-氨基丁酸B受体(GABAB receptor,GABABR)是最具有药理学意义的药物靶点之一,具有复杂而精细的激活机制.传统的GABABR靶点药物开发集中于激动剂和拮抗剂,这类药物受到多种因素的制约,包括较强的副作用、药物代谢困难、机体耐药性明显等.变构剂结合于正构位点之外,能够调节GABABR异源二聚体亚基或结构域间的相互作用.正向变构剂(positive allosteric modulators,PAMs)和负向变构剂(negative allosteric modulators,NAMs)分别可以提高或降低GABABR的活性,并具有较高的特异性和药物安全性,同时还能够保持GABABR信号在时间和空间上的可控性.变构剂为GABABR靶点药物开发提供了新思路.     

Collagen metabolism and phenotype after prostaglandin E2 treatment of granuloma: direct and macrophage-modulated effects

Local administration of PGE₂ (2 μg) to polyether sponges, implanted s.c. in rats, inhibited hydroxyproline and total protein accumulation, without altering relative amounts of collagen, when administered early during granuloma development. In contrast, while DNA as well as total protein accumulation was inhibited by local PGE₂ treatment of established granuloma, hydroxyproline accumulation and the relative amounts of collagen were enhanced. This PGE₂-induced collagen enhancement was associated with an increased type III : type I collagen ratio, possibly due to differential intracellular breakdown of newly synthesized collagen. The solubility of granuloma collagen was unaffected by PGE₂. Impregnation of sponges with carrageenan before implantation, thereby giving macrophage-dominated granuloma, did not affect the changes in protein and DNA induced by later treatment with PGE₂, but did reverse the PGE₂-induced accumulation of hydroxyproline. This latter effect probably reflects macrophage-mediated, PGE₂ enhancement of collagenolytic activity.     

Nonneural components in the response of fresh human airways to electric field stimulation

Fresh human bronchi, obtained at thoracotomy and maintained at 37 degrees C, were studied in vitro to investigate their response to electric field stimulation (EFS). We found complex responses that were not only composed of a rapid initial nerve-mediated cholinergic contraction and a non-adrenergic nerve-mediated relaxation, but, in 80% of preparations, also of a tonic contraction with a sustained time course. This sustained phase was not blocked by the nervous conductance blocker tetrodotoxin (TTX) and was therefore not neurally mediated. Controlled transient cooling to 4 degrees C in the organ bath reduced this sustained phase selectively for several hours. The leukotriene (LT) antagonist FPL 55712, dexamethasone, which inhibits phospholipase A2, and the antiasthmatic drug cromolyn all reduced the sustained phase significantly. In 20% of strips, an additional TTX-resistant contraction was seen directly after the cholinergic phase. This contraction could be inhibited by indomethacin. A similar small peak sometimes appeared after selective blocking of either the cholinergic or the sustained phases. Experiments in which the epithelium was removed from the strips suggested that this indomethacin-sensitive response, but not the sustained phase, was dependent on the presence of epithelium. These results show that EFS of fresh human bronchi stimulated cholinergic and nonadrenergic inhibitory nerves and gave rise to a partly epithelium-dependent synthesis of arachidonic acid metabolites, which caused contractile responses that interfered with the neurally mediated responses.     

MiR-21在结缔组织病并间质性肺病患者外周血中的表达及临床意义

目的:探讨miR-21在结缔组织病(Connective tissue disease, CTD)并间质性肺病(Interstitial lung disease, ILD)患者外周单个核细胞中的表达及临床意义。方法:选择2015年1月-2018年6月我院收治的202例CTD患者,将其分为CTD-ILD组(n=58)和CTD无ILD组(n=152),对CTD-ILD患者的临床资料进行归纳分析,对不同结缔组织病合并间质性肺疾病组间的临床表现、胸部影像表现进行比较分析。收集两组外周血分离其外周血单个核细胞并采用实时荧光定量PCR法检测各组外周血单个核细胞中miR-21的表达水平,分析CTD-ILD组miR-21与患者临床特征的关系。结果:CTD-ILD的影像学表现多种多样:网格影在SSc、RA、PM/DM患者中多见;蜂窝影多见于SSc的患者;实变影多见于SLE、PM/DM的患者。CTD-ILD组外周单个核细胞中miR-21表达水平较对照组增高,并与肺功能DLCO呈负相关。结论:不同CTD-ILD的发病率不同,临床特点及影像学也各有差异。miR-21对评估CTD-ILD的病变严重程度具有一定价值,可作为诊断CTD-ILD的血清标志物辅助ILD早期诊断与病变程度评估。