表达LTB乳酸杆菌提高艰难梭菌类毒素疫苗黏膜免疫效应的研究

目的 通过构建大肠埃希菌热敏性肠毒素B亚单位 (heat labile enterotoxin B subunit, LTB) 乳酸杆菌表达载体,研究其对艰难梭菌类毒素疫苗的黏膜免疫保护效应。方法 克隆LTB基因,制备pSIP411-LTB重组质粒,电转化到乳酸杆菌中,制备乳酸杆菌表达LTB载体;通过透析和层析等技术纯化艰难梭菌A毒素和B毒素,经甲醛处理获得的艰难梭菌A毒素和B毒素的类毒素作为疫苗候选抗原;在第0 d、第14 d和第28 d皮下接种小鼠艰难梭菌类毒素和口服乳酸杆菌表达LTB载体;在初次接种后第0 d、10 d、24 d和38 d检测抗A毒素和B毒素的血清IgG和粪便IgA;第34 d,小鼠经口感染艰难梭菌,观察疫苗保护效果。结果 成功构建了LTB乳酸杆菌佐剂表达载体和制备了艰难梭菌A毒素和B毒素的内毒素;各疫苗组和疫苗+LTB佐剂组小鼠在感染艰难梭菌后,均无腹泻、体重减轻和死亡现象,而对照组老鼠腹泻发病率为100%,死亡率42.86%,5 d体重下降0.83 g;在初次接种后的10 d、24 d和38 d,与空白组比较,各疫苗组抗A毒素或B毒素的血清IgG及粪便IgA显著升高(F=284.93,1 037.05,696.82,74,184.07,166.95,P<0.01);与疫苗组比较,接种疫苗+LTB佐剂组的血清IgG及粪便IgA显著升高(F=21.88,27.22,8.31,56.49,63.76,101.78,P<0.05)。结论 艰难梭菌A毒素和B毒素的类毒素作为疫苗的候选抗原对艰难梭菌的感染具有很好的保护效应,LTB乳酸杆菌载体表达佐剂能够提高免疫动物的抗体效价,增强黏膜免疫效应。     

Effect of Probiotic Supplement on Cytokine Levels in HIV-Infected Individuals: A Preliminary Study

Inflammation persists in patients infected with HIV. Reduction of inflammatory cytokines and microbial translocation might be one way that this could be managed. Purpose: The anti-inflammatory properties of certain probiotic strains prompted us to investigate whether a probiotic could reduce the inflammatory index of HIV-infected patients. Methods: The study involved 30 HIV+ males on antiretroviral therapy, who were given one bottle of fermented milk Yakult Light^® containing Lactobacillus casei Shirota (LcS) twice a day for four weeks. Results: The probiotic LcS was associated with an increase of T lymphocytes and a significant increase of CD56+ cells (p = 0.04). There was also a significant decrease of mRNA levels of TGFβ, IL-10 and IL-12 (p < 0.001) and IL-1β expression (p < 0.001) and an increase of serum IL-23 (p = 0.03). In addition, decreased inflammation and cardiovascular risk were observed, as shown by a reduction of cystatin C (p < 0.001). Conclusions: These data provide preliminary evidence that probiotic supplementation may modulate certain immunological parameters and some of the cytokines that were analyzed. Thus, we propose that LcS may be an inexpensive and practical strategy to support the immune function of HIV+ patients.     

Antimicrobial activity of selected synbiotics targeted for the elderly against pathogenic Escherichia coli strains

The aim of the present study was to evaluate the antimicrobial activity of two synbiotic combinations, Lactobacillus fermentum with short-chain fructooligosaccharides (FOS-LF) and Bifidobacterium longum with isomaltooligosaccharides (IMO-BL), against enterohaemorrhagic Escherichia coli O157:H7 and enteropathogenic E. coli O86. Antimicrobial activity was determined (1) by co-culturing the synbiotics and pathogens in batch cultures, and (2) with the three-stage continuous culture system (gut model), inoculated with faecal slurry from an elderly donor. In the co-culture experiments, IMO-BL was significantly inhibitory to both E. coli strains, while FOS-LF was slightly inhibitory or not inhibitory. Factors other than acid production appeared to play a role in the inhibition. In the gut models, both synbiotics effectively inhibited E. coli O157 in the first vessel, but not in vessels 2 and 3. E. coli O86 was not significantly inhibited.     

Effects of a synbiotic on symptoms,and daily functioning in attention deficit hyperactivity disorder – A double-blind randomized controlled trial

Some prebiotics and probiotics have been proposed to improve psychiatric symptoms in children with autism. However, few studies were placebo-controlled, and there is no study on persons with an attention deficit hyperactivity disorder (ADHD) diagnosis. Our aim was to study effects of Synbiotic 2000 on psychiatric symptoms and functioning in children and adults with ADHD without an autism diagnosis. Children and adults (n = 182) with an ADHD diagnosis completed the nine weeks randomized double-blind parallel placebo-controlled trial examining effects of Synbiotic 2000 on the primary endpoints ADHD symptoms, autism symptoms and daily functioning, and the secondary endpoint emotion regulation, measured using the questionnaires SNAP-IV, ASRS, WFIRS, SCQ, AQ and DERS-16. Levels at baseline of plasma C-reactive protein and soluble vascular cell adhesion molecule-1 (sVCAM-1), central to leukocyte-endothelial cell adhesion facilitating inflammatory responses in tissues, were measured using Meso Scale Discovery. Synbiotic 2000 and placebo improved ADHD symptoms equally well, and neither active treatment nor placebo had any statistically significant effect on functioning or sub-diagnostic autism symptoms. However, Synbiotic 2000, specifically, reduced sub-diagnostic autism symptoms in the domain restricted, repetitive and stereotyped behaviors in children, and improved emotion regulation in the domain of goal-directed behavior in adults. In children with elevated sVCAM-1 levels at baseline as well as in children without ADHD medication, Synbiotic 2000 reduced both the total score of autism symptoms, and the restricted, repetitive and stereotyped behaviors. In adults with elevated sVCAM-1 at baseline, Synbiotic 2000 significantly improved emotion regulation, both the total score and four of the five subdomains. To conclude, while no definite Synbiotic 2000-specific effect was detected, the analysis of those with elevated plasma sVCAM-1 levels proposed a reduction of autism symptoms in children and an improvement of emotion regulation in adults with ADHD.Trial registration number: ISRCTN57795429.     

阴道微生态菌群与宫颈疾病相关性的研究进展

宫颈疾病包括宫颈炎症、宫颈鳞状上皮内病变及宫颈癌,近年研究发现阴道微生物菌群产生的细胞因子及局部免疫系统与宫颈疾病的发生、发展有关。正常女性的阴道微生态环境由多种微生物构成,其中乳杆菌对维持阴道微生态平衡发挥着重要作用。宫颈癌在女性恶性肿瘤中发生率位居第一,其发生与人乳头瘤病毒(HPV)持续感染密切相关,但并非所有感染HPV者均患宫颈癌,其病因为多因素综合作用。因乳杆菌变化导致的阴道疾病与HPV感染相互作用,共同参与宫颈疾病的发生、进展,系统有效的阴道微生态环境检测对及时调节阴道微生态平衡非常重要。阴道微生物菌群与宫颈疾病之间的关系成为许多学者的研究热点,综述阴道微生态与宫颈疾病发生、发展的相关性,为宫颈疾病尤其是宫颈癌的预防、治疗及预后提供理论依据。     

Catalase-mimetic gold nanoparticles inhibit the antagonistic action of Lactobacillus gasseri toward foodborne enteric pathogens in associative cultures

Gold nanoparticles (AuNPs) have been previously shown to induce gut dysbiosis during colitis in mice, but the underlying mechanism is not clear yet. Here, we evaluated the effects of AuNPs (5?nm diameter, coated with tannic acid, polyvinylpyrrolidone or citrate) on H₂O₂ accumulation and pathogen antagonization by an intestinal strain of Lactobacillus gasseri under aerobic cultural conditions. AuNPs (0.65?μg/mL) reduced over 50% of H₂O₂ accumulation by L. gasseri, and significantly inhibited the antagonistic action of L. gasseri on growth of four foodborne enteric pathogens, i.e. Salmonella enterica serovar Typhimurium, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus in associative cultures.     

乳酸杆菌活菌联合特比萘芬治疗念珠菌性阴道炎的疗效观察

目的观察乳酸杆菌活菌联合特比萘芬治疗念珠菌性阴道炎的临床疗效。方法选取2016年1月—2016年12月在中国人民解放军第四五七医院就诊的念珠菌性阴道炎患者106例,随机分为对照组和治疗组,每组各53例。对照组口服盐酸特比萘芬片,0.25 mg/次,1次/d;治疗组在对照组基础上阴道深部放入阴道用乳杆菌活菌胶囊,1粒/次,1次/晚。两组患者均治疗12周。观察两组患者临床疗效,比较治疗前后两组患者临床症状评分和临床症状体征改善时间。结果治疗后,对照组临床总有效率为79.25%,显著低于治疗组的92.45%。两组比较差异具有统计学意义(P0.05)。治疗后,两组患者外阴瘙痒和灼痛感评分均明显降低(P0.05);且治疗组上述临床症状评分比对照组更低(P0.05)。治疗组患者临床症状体征开始改善时间明显短于对照组,两组比较差异具有统计学意义(P0.05)。结论乳酸杆菌活菌联合特比萘芬治疗念珠菌性阴道炎疗效显著,可明显改善患者临床症状,不良反应较少,具有一定的临床推广应用价值。     

妇肤康喷雾剂联合乳杆菌活菌胶囊治疗产后阴道炎的疗效观察

目的探讨妇肤康喷雾剂联合乳杆菌活菌胶囊治疗产后阴道炎的临床疗效。方法选取2015年1月—2017年1月郑州市第二人民医院收治的产后阴道炎患者78例,随机分为对照组和治疗组,每组各39例。对照组患者阴道深部放入阴道用乳杆菌活菌胶囊,1粒/次,1次/d。治疗组患者在对照组基础上外阴喷洒妇肤康喷雾剂,3~5揿/次,2次/d。两组均持续治疗10 d。评价两组患者临床疗效,同时比较治疗前后两组患者阴道症状、阴道p H值和复发情况。结果治疗后,对照组和治疗组的临床有效率分别为76.92%和94.87%,两组比较差异具有统计学意义(P0.05)。治疗后,两组患者p H值和阴道炎症评分较治疗前显著降低,阴道健康状况评分明显提高,同组治疗前后比较差异具有统计学意义(P0.05);且治疗后治疗组p H值和阴道炎症评分显著低于对照组,阴道健康状况评分高于对照组,两组比较差异具有统计学意义(P0.05)。治疗后,治疗组总复发率为5.13%,显著低于对照组的12.82%,两组比较差异具有统计学意义(P0.05)。结论妇肤康喷雾剂联合乳杆菌活菌胶囊治疗产后阴道炎可改善阴道局部微环境,降低复发率,具有一定的临床推广应用价值。     

In vitro and in silico characterisation of Lactobacillus paraplantarum D2-1, a starter culture for soymilk fermentation

Soymilk contains several functional nutrients and is thus a promising ingredient for production of functional foods. The present research aimed to study starter properties, functional characteristics and safety of Lactobacillus paraplantarum D2-1, a promising starter culture for soymilk fermentation. Strain D2-1 actively fermented soymilk within 24?h but had weak activity of additional acid production after 7 d. Succinate and acetoin, which could be linked to flavour and taste, were accumulated in fermented soymilk. In vitro study revealed that the organism has several beneficial properties, including high survival ability in artificial gastric juice, high abilities of mucus adhesion and biofilm formation and production of γ-aminobutyric acid and conjugated linoleic acid, without any significant risks for consumption. Genome sequencing supported the desirable metabolic properties of the strain. These results indicate that L. paraplantarum D2-1 is a suitable starter for soymilk fermentation and is a promising probiotic candidate that can be used safely.