乳杆菌对致病性大肠杆菌K88和O138体外存活抑制的动力学研究

研究了一株分离自断奶仔猪小肠黏膜的肠乳杆菌L1(Lactobacillus intestinalis)体外发酵特性,及其代谢产物对病原性大肠杆菌Escherichia coli K88和O138存活的影响。体外发酵结果表明:发酵12h后,L1菌液pH值迅速降至3.90,并产生大量乳酸,为104.08mmol/L。L1菌株代谢产物对K88和O138体外生长抑制的动力学研究表明:L1菌株代谢产物对K88和O138存活具有很强的抑制作用;L1菌株发酵液与含相同浓度乳酸的自制培养液比较结果表明:乳酸在L1菌株代谢物对K88和O138存活抑制中发挥了主要作用;K88和O138对pH4.5的MRS培养液具有一定的耐受能力。

双歧杆菌、肠球菌、乳杆菌和芽孢杆菌四联活菌肠溶胶囊治疗慢性腹泻的临床效果

目的观察分析双歧杆菌、肠球菌、乳杆菌和芽孢杆菌四联活菌肠溶胶囊治疗慢性腹泻的临床效果。方法采用随机数字表法将我院60例慢性腹泻的患者分为两组,其中对照组采用常规治疗慢性腹泻,实验组采用双歧杆菌、肠球菌、乳杆菌和芽孢杆菌四联活菌肠溶胶囊治疗慢性腹泻,观察并比较两组患者经过治疗后的临床效果。结果两组患者经过治疗后,实验组总有效率(96.67%)明显高于对照组总有效率(70.00%),统计学上有意义(P<0.05)。结论采用双歧杆菌、肠球菌、乳杆菌和芽孢杆菌四联活菌肠溶胶囊治疗慢性腹泻临床总有效率高,安全,有效,应该在临床上广泛应用。

人免疫球蛋白联合双歧杆菌乳杆菌三联活菌肠溶胶囊治疗重症手足口病对患儿细胞免疫功能的影响

目的分析人免疫球蛋白联合双歧杆菌乳杆菌三联活菌肠溶胶囊治疗重症手足口病患儿对其免疫功能的影响.方法选择2017年1月—2019年12月于惠州市第一妇幼保健院就诊的120例重症手足口病患儿为研究对象,按随机数字表法分为试验组(n=60)与对照组(n=60),2组均按指南给予基础对症治疗,试验组患儿采用人免疫球蛋白联合双歧杆菌乳杆菌三联活菌肠溶胶囊,对照组患儿采用人免疫球蛋白常规治疗.观察记录2组患儿治疗前后血清C反应蛋白(CRP)、白细胞介素-17(IL-17)、免疫球蛋白G(IgG)、免疫球蛋白M(IgM)的变化,记录口腔溃疡愈合时间、体温恢复时间以及皮疹消退时间,观察患儿症状改善情况.结果试验组体温恢复、皮疹消退时间短于对照组,CRP、IL-17与免疫球蛋白IgG优于对照组,病情加重率低于对照组(P<0.05).结论人免疫球蛋白联合双歧杆菌乳杆菌三联活菌肠溶胶囊治疗重症手足口病疗效显著,对促进患儿免疫功能恢复有重要意义.

Probiotics for gastrointestinal disorders: Proposed recommendations for children of the Asia-Pacific region

Recommendations for probiotics are available in several regions. This paper proposes recommendations for probiotics in pediatric gastrointestinal diseases in the Asia-Pacific region. Epidemiology and clinical patterns of intestinal diseases in Asia-Pacific countries were discussed. Evidence-based recommendations and randomized controlled trials in the region were revised. Cultural aspects,health management issues and economic factors were also considered. Final recommendations were approved by applying the Likert scale and rated using the GRADE system. Saccharomyces boulardii CNCM I-745(Sb) and Lactobacillus rhamnosus GG(LGG) were strongly recommended as adjunct treatment to oral rehydration therapy for gastroenteritis. Lactobacillus reuteri could also be considered. Probiotics may be considered for prevention of(with the indicated strains): antibiotic-associated diarrhea(LGG or Sb); Clostridium difficile-induced diarrhea(Sb); nosocomial diarrhea(LGG); infantile colic(L reuteri) and as adjunct treatment of Helicobacter pylori(Sb and others). Specific probiotics with a history of safe use in preterm and term infants may be considered in infants for prevention of necrotizing enterocolitis. There is insufficient evidence for recommendations in other conditions. Despite a diversity of epidemiological,socioeconomical and health system conditions,similar recommendations apply well to Asia pacific countries. These need to be validated with local randomized-controlled trials.

Probiotic bacteria change Escherichia coli-induced gene expression in cultured colonocytes:Implications in intestinal pathophysiology

AIM: To investigate the change in eukaryotic gene expression profile in Caco-2 cells after infection with strains of Escherichia coli and commensal probiotic bacteria. METHODS: A 19 200 gene/expressed sequence tag gene chip was used to examine expression of genes after infection of Caco-2 cells with strains of normal flora E. coli,Lactobacillus plantarum,and a combination of the two. RESULTS: The cDNA microarray revealed up-regulation of 155 and down-regulation of 177 genes by E. coli . L. plantarum up-regulated 45 and down-regulated 36 genes. During mixed infection,27 genes were up-regulated and 59 were down-regulated,with nullification of stimulatory/inhibitory effects on most of the genes. Expression of several new genes was noted in this group. CONCLUSION: The commensal bacterial strains used in this study induced the expression of a large number of genes in colonocyte-like cultured cells and changed the expression of several genes involved in important cellular processes such as regulation of transcription,protein biosynthesis,metabolism,cell adhesion,ubiquitination,and apoptosis. Such changes induced by the presence of probiotic bacteria may shape the physiologic and pathologic responses they trigger in the host.

Lactobacillus crispatus M206119 exacerbates murine DSS-colitis by interfering with inflammatory responses

AIM： TO investigate the role of Lactobacillus crispatus （L. crispatus） strain China Center for Type Culture Col- lection （CCTCC） M206119 in intestinal inflammation.METHODS： Forty 8-wk-old Balb/c mice （20± 2 g） were divided into four groups of 10 mice each. Three groups that had received dextran sulfate sodium （DSS） were administered normal saline, sulfasalazine or CCTCC M206119 strain, and the fourth group received none of these. We assessed the severity of colitis using a disease activity index, measured the colon length and weight, collected stools and mesenteric lymph nodes for bacterial microflora analysis. One centimeter of the proximal colon, middle colon and distal colon were collected and fixed in 10% buffered formalin, dehydrated in ethanol, and embedded in paraffin. Interleukin （IL）- 1β, IL-6 and tumor necrosis factor （TNF）-α expression was detected using reverse transcription polymerase chain reaction. Protective factors zonula occludens （ZO）-1 and β-defensin 2 were detected by immunoblot-ting. The features of CCTCC M206119 strain were identified based on morphology, biochemical profile, and 16S RNA sequencing.RESULTS： DSS-colitis animals treated with CCTCC M206119 had markedly more severe disease, with greater weight loss, diarrhea, fecal bleeding, and shortened colon length. In addition, the CCTCC-M206119- treated group had comparatively higher histologi- cal scores and more neutrophil infiltration than the controls. Expression of protective factors ZO-1 and β-defensin 2 was downregulated due to destruction of the mucosal barrier after CCTCC M206119 strain treatment. An in vitro assay demonstrated that CCTCC M206119 strain increased the nuclear translocation of nuclear factor-κB in epithelial cells. Intestinal proinflam- matory or anti-inflammatory cytokine responses were evaluated. Proinflammatory colonic cytokine （IL-Iβ, IL-6 and TNF-α） levels were clearly increased in CCTCC- M206119-treated animals, whereas anti-inflammatory colonic cytokine （IL-10） level was lowered compared with saline or 5-aminosalicylic-acid-treated DSS-colitis mice. Next, CCTCC M206119 strain was characterized as 1. crispatus by microscopic morphology, biochemical tests and 16S rRNA gene level.CONCLUSION： Not all lactobacilli are beneficial for in- testinal inflammation, and L. crispatus CCTCC M206119 strain is involved in exacerbation of intestinal inflamma- tion in DSS-colitis mice.

Effects of Lactobacillus plantarum on gut barrier function in experimental obstructive jaundice

AIM:To investigate the mechanisms of Lactobacillus plantarum(L.plantarum)action on gut barrier in preoperative and postoperative experimental obstructive jaundice in rats.METHODS:Forty rats were randomly divided into groups of sham-operation,bile duct ligation(BDL),BDL +L.plantarum,BDL+internal biliary drainage(IBD),and BDL+IBD+L.plantarum.Ten days after L.plantarum administration,blood and ileal samples were collected from the rats for morphological examination,and intestinal barrier function,liver function,intestinal oxidative stress and protein kinase C(PKC)activity measurement.The distribution and expression of the PKC and tight junction(TJ)proteins,such as occludin,zonula occludens-1,claudin-1,claudin-4,junction adhesion molecule-A and F-actin,were examined by confocal laser scanning microscopy,immunohistochemistry,Western blotting,real-time fluorescent quantitative polymerase chain reaction assay.RESULTS:L.plantarum administration substantially restored gut barrier,decreased enterocyte apoptosis,improved intestinal oxidative stress,promoted the activity and expression of protein kinase(BDL vs BDL+L.plantarum,0.295±0.007 vs 0.349±0.003,P<0.05;BDL+IBD vs BDL+IBD+L.plantarum,0.407±0.046 vs 0.465±0.135,P<0.05),and particularly enhanced the expression and phosphorylation of TJ proteins in the experimental obstructive jaundice(BDL vs BDL+L.plantarum,0.266±0.118 vs 0.326±0.009,P<0.05).The protective effect of L.plantarum was more prominent after internal biliary drainage(BDL+IBD vs BDL +IBD+L.plantarum,0.415±0.105 vs 0.494±0.145,P<0.05).CONCLUSION:L.plantarum can decrease intestinal epithelial cell apoptosis,reduce oxidative stress,and prevent TJ disruption in biliary obstruction by activating the PKC pathway.

Behavioral interactions between a coexisting rodent Micaelamys namaquensis and macroscelid Elephantulus myurus

A number of mechanisms are known to influence coexistence in small mammal communities. However, the role ofbehavioral interactions in promoting species coexistence is under-represented in the literature. We studied the behavioral interactionsof two coexisting small mammals, the Namaqua rock mouse Micaelamys namaquensis (Rodentia) and the Rock sengi Elephantulusmyurus (Macroscelidae), which have high dietary and microhabitat overlap. Using wild-caught individuals, intra- andinterspecific dyadic encounters were staged in tanks on a neutral rocky outcrop. Interspecific dyads displayed significantly moreactive avoidance behavior. There was no support for the prediction that the larger, more specialist species, E. myurus, is behaviorallydominant over M. namaquensis. Intraspecific encounters of E. myurus showed significantly more passive avoidance andamicable behavior, whereas the behavior of M. namaquensis did not differ between intra- and inter-specific encounters, both ofwhich were characterized by low levels of aggression and amicability. Thus, due to the lack of aggression, direct competition appearsweak and instead mutual avoidance may reduce or minimize interspecific interactions, potentially promoting coexistence.

Enzymatic Activity of Escherichia Coil Lactate Dehydrogenase and Cytochrome c Oxidase

The catalytic activity of two common bacterial enzymes, lactate dehydrogenase （LDH） and cytochrome c oxidase （COX） from Escherichia coli was examined following bacterial exposure to microwave （MW） radiation under well-defined experimental conditions. The experiments were conducted in a specialized microwave processing apparatus, with an exposure frequency of 18 GHz, and a temperature profile that was restricted to below 40℃ to avoid thermal degradation of the bacteria. The absorbed power was calculated to be 1,500 kW/m3 and the electric field was determined to be 300 Wm. Both values were theoretically confirmed using Computer Simulation Technology （CST） Microwave Studio 3D Electromagnetic Stimulation Software. Results showed that the activity of both enzymes was increased following MW radiation compared to negative controls and thermally treated samples subjected to similar temperature profiles. It is suggested that the increase in COX and LDH enzyme activity could not be explained by conventional heating alone, but was rather a result of micro-thermal effects that incorporated ＇undetectable＇ thermal mechanisms.

Moxibustion at Front-Mu Point of Abdomen for Intestinal Dysbacteriosis in Rats

Objective：To study the moxibustion at Guanyuan（CV 4）and Tianshu（ST 25）on intestinal dvsbacteriosis in rats.Methods：Fifty Wistar rats,clearing grade,were randomly divided into 5 groups,a normal group,a model group,a medical group,and a Guanyuan（CV 4）group and a Tianshu（ST 25）group,with 10 rats in each group.The rats were treated with Lincomycin Hydrochloride via intragastric administration for developing models.The model rats were treated with medicine and moxibustion respectively.0.1 g fresh rat feces in each group were cultured on the selective culture medium of bifidobacterium species（BS）,lactobacillus（LBS）,enterobactefiaceae（EB）and enterococcus（EC）.The growth and quantity of the bacterial colony were tested by biochemical identification tubes and turbidimetry.Results：Moxibustion at Guanyuan（CV 4）increased BS and LBS while moxibustion at Tianshu（ST 25）improved EB and EC.Conclusion：Moxibustion at Front-Mu points Of different body parts selectively regulated advantaged probiotics for treating intestinal dysbactenosis.

Oral administration of Lactobacillus rhamnosus GG to newborn piglets augments gut barrier function in pre-weaning piglets

To understand the effects of Lactobacillus rhamnosus GG(ATCC 53103)on intestinal barrier function in pre-weaning piglets under normal conditions,twenty-four newborn littermate piglets were randomly divided into two groups.Piglets in the control group were orally administered with 2 mL 0.1 g/mL sterilized skim milk while the treatment group was administered the same volume of sterilized skim milk with the addition of viable L.rhamnosus at the 1st,3rd,and 5th days after birth.The feeding trial was conducted for 25 d.Results showed that piglets in the L.rhamnosus group exhibited increased weaning weight and average daily weight gain,whereas diarrhea incidence was decreased.The bacterial abundance and composition of cecal contents,especially Firmicutes,Bacteroidetes,and Fusobacteria,were altered by probiotic treatment.In addition,L.rhamnosus increased the jejunal permeability and promoted the immunologic barrier through regulating antimicrobial peptides,cytokines,and chemokines via Toll-like receptors.Our findings indicate that oral administration of L.rhamnosus GG to newborn piglets is beneficial for intestinal health of pre-weaning piglets by improving the biological,physical,and immunologic barriers of intestinal mucosa.