烧伤病人创面感染气单胞菌的研究

从521份气单胞菌所致烧伤病人创面感染的创面标本中,经生化反应分析、毒素测定,检出气单胞菌42株(80.06％),其菌种为亲水气单胞菌24株(57.14％),温合气单胞17株(40.5％),豚鼠气单胞菌1株(2.36％)。在42株气单胞菌感染中,单一菌种感染15株(35.7％),多种菌感染27株(64.3％)。     

弧菌,气单胞菌及邻单胞菌编码鉴定研究

采用编码技术对医学常见的弧菌属、气单胞菌属及邻单胞菌属的１２ 个菌种进行编码,建立了７ 位数编码鉴定法。并用此法鉴定了２０８ 株标准菌株,与常规鉴定法比较,两法无显著统计学意义（χ２ ＝０－４４ ,Ｐ＞０－０５）,符合率为９５－６７％ 。此鉴定法快捷、可靠、操作简便、判定结果简单、适合于临床、卫生及基层微生物实验室推广应用。     

嗜水气单胞菌TaqMan实时PCR检测方法的建立

Objective To develop a TaqMan real-time PCR for the detection of aeromonas hydrophila. Methods The conserved region of major adhesion gene of aeromonas hydrophila (aha) was used to design primers and TaqMan probe. A total of six concentration gradients for forward and reverse primers ranging from 200 -700 nmol/L were chosen, and four concentration gradients for probe ranging from I00 -400 nmol/L were chosen. And then the concentration of primers and probe were optimized by ANOVA of completely randomized design respectively. The specificity of the established method was evaluated by using bacteria as contrast, including 45 strains Vibrio cholerae,20 strains Vibrio parahemolyticus, 10 strains Vibrio fluvialis,4 strains Vibrio mimicus,5 strains Vibrio vulnificus, 1 strain Vibrio aiginoayticns, 1 strain Vibrio furnissii, 5 strains Salmonella, 10 strains Shigella and 2 strains Piesiomonas shigelloides. The sensitivity, bacterial sensitivity and DNA sensitivity included,were evaluated. The stool of healthy people was contaminated by aeromonas hydrephila artificially, and the ability of the established TaqMan real-time PCR system for detection of aeromonas hydrophila was also evaluated. Results The cycle threshold (Ct) value deserved from 6 groups of primers concentration gradient was (x±s) :20.69±0.33,20.72±0.21,20.81±0. 12,20.74±0.12,20.51±0. 16 and 20.69±0. 11, respectively, and the concentration of forward primer and reverse primer was determined to be 200 nmol/L (F=1.33, P=0. 28). The Ct value deserved from 4 groups of probe concentration gradient was (x±s) : 20.56±0. 08,20.82±0.05,20. 82±0. 11 and 20.93±0.09,respectively,and the concentration of probe was determined to be 100 nmol/L(F =5.26,P =O. 01 ). The bacterial sensitivity and DNA sensitivity were 80 CFU/ml and 100 fg/μl respectively,and the sensitivity to detect aeromonas hydrophila from stool was 8 × 103 CFU/ml, which might be 8 CFU/ml after 8 hours' enrichment. No amplification was observed in the templates of other bacterial. Conclusion The TaqMan real-time PCR method targeting the aha gene of aeromonas hydrophila had a high sensitivity and specificity and might be used to detect aeromonas hydrophila from pure bacterial and stool rapidly.     

Immunomodulatory effect of Aegle marmelos leaf extract on freshwater fish Cyprinus carpio infected by bacterial pathogen Aeromonas hydrophila

Context: Aquatic organisms (especially fish) require potent defense mechanisms to protect themselves against pathogen invasion and disease formation. The use of immunostimulants in fish culture can prevent the diseases through augmentation of both specific and non-specific immunity.

Objective: A study was conducted to investigate the efficacy of different dietary doses of Aegle marmelos (Linn.) Corr. Serr. (Rutaceae) leaf extract for the immune response and the disease resistance of the freshwater fish, Cyprinus carpio Linn. (Cyprinidae) infected by Aeromonas hydrophila Chester (Aeromonadaceae).

Materials and Methodology: Hematological, specific immune response, non-specific immune response and enzyme assay studies were performed on fish and were scrutinized after 50 days of feeding trial.

Results: Fish were challenged with Aeromonas hydrophila at a dose of 1.5?×?10⁴ cells/mL through intraperitoneal injection, and the hematological changes, the immune response, the enzyme activity and the disease resistance of Cyprinus carpio against the pathogen were also studied for 20 days at 5-day intervals.

Discussion: The results obtained from the study demonstrated that the fish fed with leaf extract of Aegle marmelos incorporated into feed significantly enhanced the red blood cell count, white blood cell count, hemoglobin, phagocytic activity, nitroblue tetrazolium chloride assay, lysozyme, pathogen clearance and enzyme activity compared with the control group. The survivability was higher in the fish which consumed leaf extract-incorporated feed, and the fish group fed with 5?g diet showed highest percentage survival of the fish.

Conclusion: These results indicate that Aegle marmelos stimulates the immunity and makes the freshwater fish Cyprinus carpio more resistant to Aeromonas hydrophila.     

1例急性白血病并发气单胞菌化脓性骨髓炎患者的护理

总结1例急性白血病并发左下肢气单胞菌化脓性骨髓炎患者的护理经验。护理要点包括:采取针对性医院感染防控措施;积极预防及处理感染性休克、贫血、出血、深静脉血栓、肢体功能障碍等并发症;保持营养支持和血糖控制之间的平衡;加强出院宣教,提高患者治疗和随访依从性。经过30 d的治疗和护理,患者骨髓炎好转后出院。患者出院后2个月随访骨髓炎未复发,手术切口愈合良好,顺利接受异基因造血干细胞移植。     

肠道内、外感染气单胞菌的菌种分布特征及毒力基因分析

目的了解肠道内、外分离气单胞菌菌种分布及毒力基因谱的差异,探究该菌致病性与感染部位的关系。方法收集2013年5月至2015年9月急性腹泻患者及肠道外标本来源的气单胞菌156株,采用PCR方法检测其18种毒力基因hlyA、aerA、act、alt、ast、aexT、ascV、aopP、asc F-G、gcat、tapA、fla、Ser、exu、ahyB、epr CAI、lip、laf,并统计分析肠道内、外来源气单胞菌毒力基因谱的差异。结果 156株气单胞菌中肠道内气单胞菌79株,以豚鼠气单胞菌为主(51.9%);肠道外气单胞菌77株,主要为嗜水气单胞菌(48.1%)和豚鼠气单胞菌(39.0%)。gcat、act、fla、ahyB、exu、lip基因在肠道内、外气单胞菌中的检出率较高(45.57%),而aexT、aopP、asc F-G、ascV则较低(20.78%);gcat、ahyB、laf、ast、exu、lip、hlyA、aerA在肠道内气单胞菌中的检出率显著低于肠道外(P0.05);嗜水气单胞菌gcat、ahyB、exu、lip、epr CAI、hlyA在肠道外的检出率显著高于肠道内(P0.05);豚鼠气单胞菌lip、hlyA在肠道外的检出率显著高于肠道内(P0.05),而aopP反之;维氏气单胞菌毒力基因在肠道内、外的检出率差异无统计学意义。结论肠道内、外气单胞菌感染的菌种分布及携带的毒力基因谱存在差异,临床需区别对待。     

气单胞菌研究概况

气单胞菌在自然界分布广泛,除引发鱼类疫病外也可导致人体不同部位的感染,东南亚国家是腹泻病相对高发的地区,对肝胆外科术后病例有较高的机会性感染和疾病负担;全球耐药特征呈上升趋势,多重耐药（MDR）和超广谱-内酰胺酶（ESBLs）菌株与水产养殖业的抗生素过度使用后环境污染有关;不同地域气单胞菌的毒力因子存在差异。有关部门应制定措施控制水源、食品与养殖环境,降低肠道和非肠道感染的疾病负担。     

耐药嗜水气单胞菌毒力与六类抗菌药物耐药元件基因研究

目的 了解嗜水气单胞菌毒力基因与耐药基因的分布情况,为嗜水气单胞菌感染的治疗提供参考依据。方法 分离自2014年1月至2017年10月本院内科住院病人的10株嗜水气单胞菌;采用PCR法,对10株嗜水气单胞菌检测3种毒力基因与54种耐药基因,并对检测结果作样本聚类分析。结果 10株耐药嗜水气单胞菌3种重要的毒力基因检测结果,hlyA基因检出率为100.00%,aerA基因检出率为20.00%, rtxA基因无检出。10株耐药嗜水气单胞菌6种β-内酰胺酶基因, blaAQU与blaMOX基因表达AmpC型β-内酰胺酶,10株中有5株同时检出blaAQU与blaMOX基因,1株仅检出blaMOX基因, 6株AmpC酶三维试验均呈阳性。对10株耐药嗜水气单胞菌和1株敏感嗜水气单胞菌3种毒力基因与6类抗菌药物54种耐药元件基因检测结果作UPGMA法样本聚类分析, 10株耐药嗜水气单胞菌和1株敏感嗜水气单胞菌可分为A与B二个群。结论 10株耐药嗜水气单胞菌共检出β-内酰胺类、氨基糖苷类、喹诺酮类、磺胺类、氯霉素类等5类抗菌药物17种获得性耐药基因。7种可移动遗传元件标记基因,有5株检出1~3种可移动遗传元件标记基因。10株耐药嗜水气单胞菌3种毒力基因与54种耐药元件基因同步检测显示,每株至少检出1种毒力基因和2种耐药基因,嗜水气单胞菌对抗菌药物的耐药率上升必须严密监测。     

Variations in the expressed antimicrobial peptide repertoire of northern leopard frog (Rana pipiens) populations suggest intraspecies differences in resistance to pathogens

The northern leopard frog (Rana pipiens or Lithobates pipiens) is historically found in most of the provinces of Canada and the northern and southwest states of the United States. In the last 50 years, populations have suffered significant losses, especially in the western regions of the species range. Using a peptidomics approach, we show that the pattern of expressed antimicrobial skin peptides of frogs from three geographically separated populations are distinct, and we report the presence of four peptides (brevinin-1Pg, brevinin-1Pl, ranatuerin-2Pb, and ranatuerin-2Pc) that have not previously been found in skin secretions. The differences in expressed peptides reflect differences in the distribution of alleles for the newly described Brevinin1.1 locus in the three populations. When enriched peptide mixtures were tested for their ability to inhibit growth of the pathogenic amphibian chytrid (Batrachochytrium dendrobatidis), peptides from Minnesota or Vermont frogs were more effective that peptides from Michigan frogs. Four of the purified peptides were tested for their ability to inhibit growth of two bacterial pathogens (Aeromonas hydrophila and Staphylococcus epidermidis) and B. dendrobatidis. Three of the four were effective inhibitors of B. dendrobatidis and S. epidermidis, but none inhibited A. hydrophila. We interpret these differences in expression and activity of antimicrobial peptides as evidence to suggest that each population may have been selected to express a suite of peptides that reflects current and past encounters with skin microbes.     

自发性气单胞菌腹膜炎

自发性气单胞菌腹膜炎的发生在肝硬化腹水患者中并不罕见。本文就如何诊断及预防自发性气单胞菌腹膜炎,提高患者预后综述如下。