影响杏黄兜兰种子萌发的因素

通过在不同条件下杏黄兜兰 (Paphiopedilumarmeniacum)种子萌发的观察 ,对影响其萌发的诸因子报道如下 :1)果实的生长期与种子的萌发率有关。实验表明种子采自生长期为 6 0d的果实 ,发芽率为 3 5 % ,采自 12 0d的果实 ,发芽率为 4 0 % ,采自 180d的果实 ,发芽率为 18 3%。 2 )培养基也会影响到种子的萌发 ,种子在 1 5MS内培养 ,萌发率明显高于培养于MS ,RE和改良HyponexNo 1内的种子。 3)培养基 (1 5MS)掺入添加物也会影响到种子的萌发率 ,如掺入 10 %椰子水会促使种子的萌发率达到很高的水平 ,掺入马铃薯泥 (5 0g L)或胰化胨 (2g L) ,种子的萌发率会达到较高的水平 ,而掺入香蕉泥则会对种子的萌发率产生负面影响 ,掺入活性炭 (2g L)会促使种子萌发和幼苗发育。 4 )与固态培养基相比 ,种子在液体悬浮培养基内的萌发速度更快 ,幼苗更为整齐划一。     

The effects of Escherichia coli capsule, O-antigen, host neutrophils, and complement in a rat model of Gram-negative pneumonia

Gram-negative enteric bacilli are agents of life-threatening pneumonia. The role of the bacterial capsule and O-antigen moiety of lipopolysaccharide in the pathogenesis of Gram-negative pneumonia was assessed. In a rat model of pneumonia the LD(50) of a wild-type extraintestinal pathogenic Escherichia coli strain (CP9) was significantly less than its isogenic derivatives deficient in capsule (CP9.137), O-antigen (CP921) or both capsule and O-antigen (CP923) (P< or =0.003). Studies using complement depleted or neutropenic animals established that both neutrophils and complement are important for the pulmonary clearance of E. coli. Data from these studies also support that capsule and O-antigen serve, at least in part, to counter the complement and neutrophil components of the pulmonary host defense response. Lastly, the contribution of E. coli versus neutrophils in causing lung injury was examined. Findings suggest that E. coli virulence factors and/or non-neutrophil host factors are more important mediators of lung injury than neutrophils. These findings extend our understanding of Gram-negative pneumonia and have treatment implications.     

Role of capsule in Klebsiella pneumoniae virulence: lack of correlation between in vitro and in vivo studies

In vitro and in vivo models were used to investigate the role of capsule on the virulence of Klebsiella pneumoniae. We showed that capsule expression reduces dramatically the ability of the K. pneumoniae to bind to epithelial cells when compared to its non-capsulated variant. The presence/absence of capsule had no effect on the colonization of the gastrointestinal tract, while in the urinary tract we established that capsule is an important virulence factor. Our study demonstrates the caution needed when extrapolating from results of in vitro studies and emphasizes the necessity of in vivo models in studies of bacterial virulence.     

盆炎净胶囊的成型工艺研究

目的:降低盆炎净制剂的辅料用量,提高其制剂水平。方法:比较制粒工艺,考察选定制粒工艺颗粒的休止角、堆密度、临界相对湿度,选择胶囊型号,计算所需淀粉辅料的比例。结果:选择干法制粒工艺,测定所制颗粒的休止角为33.24°,堆密度为0.834g/ml,临界相对湿度为48%,选定0号胶囊,算得所需淀粉辅料所占的比例为7.27%。结论:所研制的盆炎净胶囊制剂,降低了辅料用量,提高了原有制剂水平。     

Comprehensive molecular,genomic and phenotypic analysis of a major clone of Enterococcus faecalis MLST ST40

Background

Enterococcus faecalis is a multifaceted microorganism known to act as a beneficial intestinal commensal bacterium. It is also a dreaded nosocomial pathogen causing life-threatening infections in hospitalised patients. Isolates of a distinct MLST type ST40 represent the most frequent strain type of this species, distributed worldwide and originating from various sources (animal, human, environmental) and different conditions (colonisation/infection). Since enterococci are known to be highly recombinogenic we determined to analyse the microevolution and niche adaptation of this highly distributed clonal type.

Results

We compared a set of 42 ST40 isolates by assessing key molecular determinants, performing whole genome sequencing (WGS) and a number of phenotypic assays including resistance profiling, formation of biofilm and utilisation of carbon sources. We generated the first circular closed reference genome of an E. faecalis isolate D32 of animal origin and compared it with the genomes of other reference strains. D32 was used as a template for detailed WGS comparisons of high-quality draft genomes of 14 ST40 isolates. Genomic and phylogenetic analyses suggest a high level of similarity regarding the core genome, also demonstrated by similar carbon utilisation patterns. Distribution of known and putative virulence-associated genes did not differentiate between ST40 strains from a commensal and clinical background or an animal or human source. Further analyses of mobile genetic elements (MGE) revealed genomic diversity owed to: (1) a modularly structured pathogenicity island; (2) a site-specifically integrated and previously unknown genomic island of 138 kb in two strains putatively involved in exopolysaccharide synthesis; and (3) isolate-specific plasmid and phage patterns. Moreover, we used different cell-biological and animal experiments to compare the isolate D32 with a closely related ST40 endocarditis isolate whose draft genome sequence was also generated. D32 generally showed a greater capacity of adherence to human cell lines and an increased pathogenic potential in various animal models in combination with an even faster growth in vivo (not in vitro).

Conclusion

Molecular, genomic and phenotypic analysis of representative isolates of a major clone of E. faecalis MLST ST40 revealed new insights into the microbiology of a commensal bacterium which can turn into a conditional pathogen.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1367-x) contains supplementary material, which is available to authorized users.     

不同剂量瑞舒伐他汀联合通心络胶囊治疗冠心病合并高脂血症患者的疗效观察

目的:探讨不同剂量瑞舒伐他汀联合通心络胶囊治疗冠心病合并高脂血症患者的疗效。方法:按照随机数字表法将2017年4月至2018年5月内蒙古医科大学附属医院接诊的120例冠心病合并高脂血症患者分为低剂量联合组(5 mg瑞舒伐他汀+通心络胶囊)、中剂量联合组(10 mg瑞舒伐他汀+通心络胶囊)、高剂量联合组(20 mg瑞舒伐他汀+通心络胶囊),每组各40例,三组均治疗12周。比较三组患者的血脂指标、治疗效果、血清炎症因子水平,观察三组患者用药期间不良反应发生情况。结果:高剂量联合组、中剂量联合组治疗总有效率高于低剂量联合组(P0.05)。治疗后,高剂量联合组、中剂量联合组的总胆固醇(TC)、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)水平低于低剂量联合组,高密度脂蛋白胆固醇(HDL-C)水平高于低剂量联合组(P0.05)。治疗后三组患者的血清超敏C反应蛋白(hs-CRP)、肿瘤坏死因子-α(TNF-α)、干扰素-γ(IFN-γ)水平随着剂量的升高而降低(P0.05)。低、中、高剂量联合组不良反应发生率比较无统计学差异(P0.05)。结论:采用10 mg和20 mg的瑞舒伐他汀联合通心络胶囊治疗冠心病合并高脂血症疗效确切,可有效改善患者血脂水平,无严重不良反应发生,且对炎症因子的改善效果成剂量依赖性,医师可根据临床实际选择用药剂量。     

Non-invasive Assessment of the Efficacy of New Therapeutics for Intestinal Pathologies Using Serial Endoscopic Imaging of Live Mice

Animal models of inflammatory bowel disease (IBD) and colorectal cancer (CRC) have provided significant insight into the cell intrinsic and extrinsic mechanisms that contribute to the onset and progression of intestinal diseases. The identification of new molecules that promote these pathologies has led to a flurry of activity focused on the development of potential new therapies to inhibit their function. As a result, various pre-clinical mouse models with an intact immune system and stromal microenvironment are now heavily used. Here we describe three experimental protocols to test the efficacy of new therapeutics in pre-clinical models of (1) acute mucosal damage, (2) chronic colitis and/or colitis-associated colon cancer, and (3) sporadic colorectal cancer. We also outline procedures for serial endoscopic examination that can be used to document the therapeutic response of an individual tumor and to monitor the health of individual mice. These protocols provide complementary experimental platforms to test the effectiveness of therapeutic compounds shown to be well tolerated by mice.     

The capsule biosynthetic locus of Pasteurella multocida A:1

Pasteurella multocida is the aetiological agent of fowl cholera, bovine haemorrhagic septicaemia and atrophie rhinitis in pigs. Many strains of P. multocida express a capsule on their surface. However, nothing is known about the capsule biosynthetic locus in P. multocida although the capsule has been implicated as a virulence factor. The entire capsule locus of P. multocida A:1 was cloned and sequenced. The locus is divided into three regions. Region 1 comprises four ORFs which are involved in the transport of the capsule polysaccharide to the surface. Region 2 comprises five ORFs whose postulated protein products are involved in the biosynthesis of the polysaccharide capsule. Region 3 comprises two ORFs whose postulated products show similarity to proteins that are involved in the phospholipid substitution of the polysaccharide capsule.