Activation of the Hog1p kinase in Isc1p-deficient yeast cells is associated with mitochondrial dysfunction, oxidative stress sensitivity and premature aging

The Saccharomyces cerevisiae Isc1p, an orthologue of mammalian neutral sphingomyelinase 2, plays a key role in mitochondrial function, oxidative stress resistance and chronological lifespan. Isc1p functions upstream of the ceramide-activated protein phosphatase Sit4p through the modulation of ceramide levels. Here, we show that both ceramide and loss of Isc1p lead to the activation of Hog1p, the MAPK of the high osmolarity glycerol (HOG) pathway that is functionally related to mammalian p38 and JNK. The hydrogen peroxide sensitivity and premature aging of isc1Δ cells was partially suppressed by HOG1 deletion. Notably, Hog1p activation mediated the mitochondrial dysfunction and catalase A deficiency associated with oxidative stress sensitivity and premature aging of isc1Δ cells. Downstream of Hog1p, Isc1p deficiency activated the cell wall integrity (CWI) pathway. Deletion of the SLT2 gene, which encodes for the MAPK of the CWI pathway, was lethal in isc1Δ cells and this mutant strain was hypersensitive to cell wall stress. However, the phenotypes of isc1Δ cells were not associated with cell wall defects. Our findings support a role for Hog1p in the regulation of mitochondrial function and suggest that constitutive activation of Hog1p is deleterious for isc1Δ cells under oxidative stress conditions and during chronological aging.     

选择性激光小梁成形术联合药物治疗激素性青光眼

目的观察选择性激光小梁成形术（Selective laser trabeculoplasty,SLT）治疗激素性青光眼的疗效和安全性。方法激素性青光眼患者15例26只眼,行360°全周小梁网SLT治疗。激光治疗光斑直径400μm,脉冲时间3 ns,能量0.6-1.0 mJ。术后随访1-12个月,观察眼压、视力及并发症等。结果 6只眼术前平均眼压（29.5±4.3）mmHg,随访末次眼压（19.0±2.6）mmHg,术后各个时间点的眼压较术前显著下降,差异具有显著意义（P〈0.05）。结论 SLT治疗激素性青光眼是一种安全有效的方法。     

志贺样毒素的研究进展

志贺样毒素（ＳＬＴ）是Ｏ１５７∶Ｈ７等出血性大肠杆菌的主要致病因子。其名称还有Ｖｅｒｏ毒素（ＶＴ）和Ｓｔｘ，包括一类结构功能相似的毒素。ＳＬＴ通过抑制蛋白合成对细胞产生效应，其主要靶细胞可能是内皮细胞，其他细胞在毒素转运或调节效应方面起作用。ＳＬＴ对细胞的效应也通过细胞凋亡实现。ＳＬＴ研究的理想动物有待于建立。目前已有多种方法用于ＳＬＴ的检测，快速简便和敏感特异是各类方法的评价标准。对于ＳＬＴ引起的疾病的治疗，有待进一步研究，预防制剂将对这类疾病的控制起重要作用     

喉癌与喉咽癌患者的SE—SLT含量检测及其意义

采用定量ELISA法对19例正常人、35例喉癌及喉咽癌患者(其中15例为术后患者)进行血浆可溶性E-选择素(SE-SLT)含量检测.结果发现,正常对照组及喉癌、喉咽癌组的SE-SLT含量分别为29.82±4.88μg/L、49.66±8.16μg/L,喉癌、喉咽癌组的血浆SE-SLT含量明显高于正常对照组(P＜0.01);喉癌、喉咽癌I、Ⅱ期组及Ⅲ、Ⅳ期组的SE-SLT含量分别为42.50±6.10μg/L、54.11±6.20μg/L,I、Ⅱ期组明显低于Ⅲ、Ⅳ期组(P＜0.01);15例手术前后测血浆SE-SLT含量分别为45.12±7.09μg/L、38.85±6.40μg/L,术后SE-SLT值明显低于术前(P＜0.01).认为喉癌、喉咽癌患者血浆SE-SLT含量与病情严重程度有关,可作为疗效观察、肿瘤转移情况的参考指标.     

Feasibility of laser trabeculoplasty in angle closure glaucoma: a review of favourable histopathological findings in narrow angles

Selective laser trabeculoplasty (SLT) has been indicated as a safe and efficient treatment for primary open‐angle glaucoma; however, recent studies have also shown positive results with the use of SLT in some clinical conditions related to primary angle‐closure glaucoma (PACG). Despite the potential benefits of SLT in selected cases of PACG, the mechanisms underlying the modifications in the trabecular meshwork tissue of patients with PACG are poorly understood. This narrative review approached both the current, limited knowledge about the histological changes observed in different forms of PACG and the clinical results of SLT treatment for PACG. Favourable outcomes of SLT in patients with PACG, specifically in areas of non‐occluded angle, need further substantiation through large controlled clinical trials. A deeper understanding of the biomolecular changes of those areas is essential to improve both laser technical details and the clinical efficacy of SLT therapy.