双歧杆菌对早产儿食道pH值的影响及临床意义

目的为探讨双歧杆菌对早产儿食道pH值的影响，及其对早产儿易发生的消化道疾病的防治意义。方法我们采用便携式24hpH值自动记录仪，对61例早产儿进行了食道pH值的动态监测。结果口服双歧杆菌活菌制剂组的30例早产儿，食道pH值明显高于未服药的对照组，t=2．4093，P＜0．05。总pH值＜4的时间占总观察时间的百分比显著小于对照组。并且治疗组发生消化道疾患的人数也较对照组少。结论早产儿口服双歧杆菌活菌制剂可以减少胃食道反流等消化道疾病的发生。     

口服转内皮抑素基因双歧杆菌制剂对肺癌的疗效

目的：探讨转人内皮抑素基因双歧杆菌口服制剂对肺癌的治疗效果。方法：选择肺癌患者118例,比较服用转内皮抑素基因双歧杆菌口服制剂前后患者症状和体征,影像学检查（X线、CT,MRI）,细胞学检查,纤维支气管镜检查及病理活检、免疫学检查（CEA）和生活质量等方面的变化。结果：服用转内皮抑素基因双歧杆菌口服制剂后患者症状和体征及生活质量等较服用前均有好转或明显好转,肺癌细胞生长被明显抑制。结论：转内皮抑素基因双歧杆菌口服制剂对肺癌有较好的治疗效果。     

匹维溴铵联合双歧三联活菌治疗肠易激综合征

目的:比较匹维溴铵联合双歧三联活菌与单剂匹维溴铵治疗肠易激综合征的疗效.方法:将84例肠易激综合征患者随机分成2组,治疗组44例,应用匹维溴铵50 mg,po,tid,加双歧三联活菌胶囊2颗,po,tid;对照组40例,应用单剂匹维溴铵50 mg,po,tid.疗程均为4周.结果:治疗组有效率97.7%,对照组有效率80.0%(P＜0.05),治疗组对缓解腹痛、腹胀、腹泻、便秘、粘液便优于对照组.结论:匹维溴铵联合双歧三联活菌是治疗肠易激综合征的有效方法.     

Expression of EspA in Lactococcus lactis NZ9000 and the detection of its immune effect in vivo and vitro

Enterhemorrhagic Escherichia coli (EPEC), an important cause of severe infantile diarrheal disease in many parts of the developing world, produced several recently described virulence determinations. Several of its virulence factors are secreted by type III secretion including EspA, which forms filamentous structures on bacterial surface bridging to the host cell’s surface. These structures on bacterial surfaces may deliver other virulence factors directly into the host cell from EHEC. In this study, EspA was expressed in Lactococcus lactis NZ9000 (L. lactis NZ9000). BALB/C mice were immunized by recombinant EspA, and mice sera were assayed for the disruption of E. coli O157:H7 interaction with the host cell. BALB/C mice which were immunized with recombinant EspA produced specific antibody titers, and the difference between the control group and the immune group is marked (P<0.05). The polyclonal mice antisera blocked E. coli O157:H7-induced host cell actin rearrangement and could label E. coli O157:H7 EspA filaments in vitro. Our present findings suggest that L. lactis may be a good candidate to produce oral vaccine, and thus entertains the possibility of developing EspA-oral vaccine in the defense of E. coli O157:H7 infection.     

Study on the additive protective effect of PGLYRP3 and Bifidobacterium adolescentis Reuter 1963 on severity of DSS-induced colitis in Pglyrp3 knockout (Pglyrp3 −/−) and wild-type (WT) mice

Background and AimsPglyrp3 is a bactericidal innate immunity protein known to sustain the habitual gut microbiome and protect against experimental colitis. Intestinal inflammation and metaflammation are commonly associated with a marked reduction of commensal bifidobacteria. Whether Pglyrp3 and bifidobacteria interact synergistically or additively to alleviate metaflammation is unknown. We investigated the extent to which Pglyrp3 and bifidobacteria regulate metaflammation and gut bacterial dysbiosis in DSS-induced mouse models of intestinal inflammation.Material & Methods8–10 weeks old male mice were used. In both WT and Pglyrp3 ?/? experiments, the mice were randomly divided into three groups of 16 mice per group: (1) a control group receiving sterile tap water, (2) an experimental group receiving sterile tap water supplemented with only 5% DSS, and (3) an experimental group receiving sterile tap water supplemented with 5% DSS and 1 × 10⁹ CFU/ml of Bifidobacterium adolescentis (B.a.) for 7 days. Wild-type (WT) littermates of the respective gene (i.e. Pglyrp3) were used as controls throughout the study. Clinical signs of general health and inflammation were monitored daily. Faecal pellet samples were analysed by qRT-PCR for microbial composition. Histology of relevant organs was carried out on day 8. Metabolic parameters and liver inflammation were determined in serum samples.ResultsIntestinal inflammation in mice of group 2 were significantly increased compared to those of control group 1. There was a significant difference in mean scores for inflammation severity between DSS-treated WT and DSS-treated Pglyrp3 ?/? mice. Buildup of key serum metabolic markers (cholesterol, triglyceride and glucose) was set off by colonic inflammation. qRT-PCR quantification showed that DSS significantly decreased the Clostridium coccoides and Bifidobacterium cell counts while increasing those of Bacteroides group in both WT and Pglyrp3 ?/? mice. These manifestations of DSS-induced dysbiosis were significantly attenuated by feeding B.a. Both the local and systemic ill-being of the mice alleviated when they received B.a.DiscussionThis study shows that Pglyrp3 facilitates recognition of bifidobacterial cell wall-derived peptidoglycan, thus leading additively to a reduction of metaflammation through an increase in the number of bifidobacteria, which were able to mitigate intestinal immunopathology in the context of Pglyrp3 blockade.     

Recombinant Lactococcus Expressing a Novel Variant of Infectious Bursal Disease Virus VP2 Protein Can Induce Unique Specific Neutralizing Antibodies in Chickens and Provide Complete Protection

Recent reports of infectious bursal disease virus (IBDV) infections in China, Japan, and North America have indicated the presence of variant, and the current conventional IBDV vaccine cannot completely protect against variant IBDV. In this study, we constructed recombinant Lactococcus lactis (r-L. lactis) expressing a novel variant of IBDV VP2 (avVP2) protein along with the Salmonella resistance to complement killing (RCK) protein, and Western blotting analysis confirmed that r-L. lactis successfully expressed avVP2-RCK fusion protein. We immunized chickens with this vaccine and subsequently challenged them with the very virulent IBDV (vvIBDV) and a novel variant wild IBDV (avIBDV) to evaluate the immune effect of the vaccine. The results show that the r-L. lactis-avVP2-RCK-immunized group exhibited a 100% protection rate when challenged with avIBDV and 100% survival rate to vvIBDV. Furthermore, this immunization resulted in the production of unique neutralizing antibodies that cannot be detected by conventional ELISA. These results indicate that r-L. lactis-avVP2-RCK is a promising candidate vaccine against IBDV infections, which can produce unique neutralizing antibodies that cannot be produced by other vaccines and protect against IBDV infection, especially against the variant strain.     

弓形虫P30基因-乳酸乳球菌重组质粒的构建及其表达

目的构建表达弓形虫昆山分离株P30基因的乳酸乳球菌表达载体L2-Ps-P30-T,并在乳酸乳球菌中表达P30蛋白。方法用BamHⅠ/XhoⅠ将P30从质粒pSK-P30中切出并克隆至质粒pSK-PsT,构建pSK-Ps-P30-T质粒;用PvuⅡ将表达元件-Ps-P30-T-从pSK-Ps-P30-T质粒中切出,以相同的酶切位点导入大肠埃希菌与乳酸乳球菌穿梭质粒pTRKL2,构建L2-Ps-P30-T质粒;通过电转化将L2-Ps-P30-T导入乳酸乳球菌中,以Western blot鉴定P30蛋白的表达。结果酶切及PCR鉴定质粒L2-Ps-P30-T构建正确,并在乳酸乳球菌中表达能被弓形虫病患者血清识别的分子质量单位为30ku的蛋白。结论重组载体L2-Ps-P30-T构建正确,电转化入乳酸乳球菌后能表达具有反应原性的P30蛋白。     

Impact of Infectious Disease after Lactococcus lactis Strain Plasma Intake in Vietnamese Schoolchildren: A Randomized,Placebo-Controlled,Double-Blind Study

Lactococcus lactis strain Plasma (LC-Plasma) is reported to have anti-viral effects via direct activation of plasmacytoid dendritic cells, which upregulate the production of type I and III interferons. A randomized, placebo-controlled, double-blind, parallel group study was designed for elementary schoolchildren, grades 1 to 3, in Vietnam. LC-Plasma or a control were administered to schoolchildren as a beverage (1.0 × 10¹¹ count LC-Plasma/day/person). The primary endpoint was to determine the efficacy of LC-Plasma in reducing the cumulative days absent from school due to upper respiratory disease (URID) and gastrointestinal disease (GID), and the secondary endpoint was to evaluate the potency of LC-Plasma on URID/GID symptoms and general well-being scores. LC-Plasma intake significantly reduced the cumulative days absent from school due to URID/GID (Odds ratio (OR) = 0.57, p = 0.004) and URID alone (OR = 0.56, p = 0.005); LC-Plasma also significantly reduced the number of cumulative fever positive days during the first 4 weeks of intervention (OR = 0.58, p = 0.001) and cumulative days with diarrhea during the last 4 weeks of the intervention period (OR = 0.78, p = 0.01). The number of positive general wellbeing days was significantly improved in the LC-Plasma group compared with the control throughout the intervention period (OR = 0.93, 0.93, p = 0.03, 0.04 in the first and last 4 weeks of the intervention, respectively). These data suggest that LC-Plasma seems to improve the health condition of elementary schoolchildren and reduces school absenteeism due to infectious disease, especially URID.     

乳酸乳球菌表达弓形虫棒状体蛋白1(ROP1)

目的　在乳酸乳球菌中表达ROP1抗原蛋白。方法　从质粒 psk -ROP1中以BamHⅠ和SalⅠ双酶切出ROP1基因 ,置换构建好的大肠杆菌 -乳酸乳球菌穿梭表达质粒L2 -PsP30T中的P30基因 ,电转化感受态乳酸乳球菌 ,以Westernblotting鉴定ROP1在乳酸乳球菌中的表达。结果　表达产物中有一约 4 3kDa的蛋白带能被弓形虫病人血清识别。结论　ROP1在乳酸乳球菌中得到了表达