No effect of oral treatment with an intestinal bacterial strain, Lactobacillus rhamnosus (ATCC 53103), on birch-pollen allergy: a placebo-controlled double-blind study

BACKGROUND: Oral probiotic bacteriotherapy with Lactobacillus rhamnosus has given promising results in small children with food allergy. We studied the effects of similar therapy in teenagers and young adults, who were allergic to birch pollen and apple food and had intermittent symptoms of atopic allergy and/or mild asthma. METHODS: We conducted a double-blind, placebo-controlled study, in which respiratory and eye symptoms and use of medications in two groups were compared. Open oral challenge tests with a slice of apple were performed trice: before, during and after the birch-pollen season. There were 18 patients in each group. They used Lactobacillus rhamnosus for 5.5 months; 2.5 months before the pollen season, 1 month during the season (May), and 2 months after. RESULTS: The results were negative. The treatment did not alleviate the symptoms of the patients or reduce their use of medication during the birch-pollen season or the subsequent 2 months. The treatment did not significantly affect the symptoms caused by apple in the oral challenge tests. CONCLUSIONS: We found no indication of a beneficial treatment effect in our patients. As the number of patients was relatively small, conclusions should be drawn with caution.     

Effect of spermicides on Lactobacillus acidophilus in vitro-nonoxynol-9 vs. Sapindus saponins

Saponins extracted from the fruit pericarp of Sapindus mukorosii were tested for their bactericidal/bacteriostatic property against Lactobacillus acidophilus. Nonoxynol-9 was used as a reference compound for the comparison of activity. Lactobacillus colonies were grown on specific medium (Rogosa SL agar) containing different concentrations of saponins and nonoxynol-9 in an atmosphere of 5% CO2/95% air at 37 degrees C for 72 h. The number and size of colonies were recorded at the end of the experiment and compared with controls. Results indicated that nearly 90% of Lactobacillus colonies with minor reduction in size thrived at 0.05% concentration of saponins whereas only 18% of colonies with approximately 75% reduction in size grew in dishes containing 0.05% nonoxynol-9. At higher concentrations of saponins, there was a gradual, dose-dependent reduction in the number and size of colonies and at 2.5% concentration there was an approximately 55% reduction in the number and 60% reduction in the size of surviving colonies. No lactobacillus colonies, however, grew in dishes containing 0.1% and higher concentrations of nonoxynol-9. The studies indicate that Sapindus saponins as compared to nonoxynol-9 are far less toxic to lactobacillus species and therefore saponins containing spermicidal preparations are likely to be more vaginal-friendly than equivalent nonoxynol-9 preparations.     

Non-Viable Lactobacillus reuteri DSMZ 17648 (Pylopass?) as a New Approach to Helicobacter pylori Control in Humans

Prevalence of infections by Helicobacter pylori, a pathogen involved in a number of gastrointestinal diseases, remains high in developing countries. Management of infections by eradication is not always an option. Lactobacillus reuteri (L. reuteri) DSMZ17648 (Pylopass™/Lonza) specifically co-aggregates H. pylori in vitro and was shown to reduce ¹³C urea breath test in vivo. In this pilot study, we tried to replicate previous findings in an independent sample and to evaluate effects of spray-drying vs. freeze-drying of cultures. A single-blinded, placebo-controlled study was done in 22 H. pylori positive, asymptomatic adults. H. pylori levels were determined by ¹³C-urea-breath method after 14 days of supplementation, as well as after 6, 12, and 24 weeks follow-up. In the test group, but not in the placebo group, a significant reduction of H. pylori was observed. For the first time, spray-dried cells of L. reuteri DSMZ17648 have been used in a human study and results are in line with the first study results, supplementing with freeze-dried material. This is of special interest as spray-drying results in dead cell material, meaning that the effect of L. reuteri must be independent of its probiotic activity. These results confirm the potential of Pylopass™ as a novel way to reduce the load of H. pylori.     

PROBIOTICS

The term “probiotic” was first used in 1965, by Lilly and Stillwell, to describe substances secreted by one organism which stimulate the growth of another. The use of antibiotics, immunosuppressive therapy and irradiation, amongst other means of treatment, may cause alterations in the composition and have an effect on the GIT flora. Therefore, the introduction of beneficial bacterial species to GI tract may be a very attractive option to re-establish the microbial equilibrium and prevent disease. Prebiotic is a non-digestible food ingredient that confers benefits on the host by selectively stimulating one bacterium or a group of bacteria in the colon with probiotic properties. Both probiotics and prebiotics are together called as Synbiotics. Various bacterial genera most commonly used in probiotic preparations are Lactobacillus, Bifidobacterium, Escherichia, Enterococcus, Bacillus and Streptococcus. Some fungal strains belonging to Saccharomyces have also been used. Probiotics have been shown to be effective in varied clinical conditions-ranging from infantile diarrhoea, necrotizing enterocolitis, antibiotic-associated diarrhoea, relapsing Clostridium difficle colitis, Helicobacter pylori infections, inflammatory bowel disease to cancer, female uro-genital infection and surgical infections. Lactobacillus rhamnosus strain GG has proven beneficial affects on intestinal immunity. It increases the number of IgA and other immunoglobulins secreting cells in the intestinal mucosa. It also stimulates local release of interferons. It facilitates antigen transport to underlying lymphoid cells, which serves to increase antigen uptake in Peyer’s patches. Probiotics are live microorganisms, so it is possible that they may result in infection in the host. The risk and morbidity of sepsis due to probiotic bacteria should be weighed against the potential for sepsis due to more pathological bacteria and the morbidity of diseases for which probiotic bacteria are being used as therapeutic agents. Also, future, well-designed placebo controlled studies with validated results are required for ascertaining the true health benefits of probiotics The important point in this regard is careful selection of the probiotic agent, its dose standardization and a thorough knowledge of its beneficial effects.     

The intestinal microflora in allergic Estonian and Swedish 2-year-old children

BACKGROUND: The prevalence of allergic diseases seems to have increased particularly over the past 35-40 years. Furthermore, allergic disease is less common among children in the formerly socialist countries of central and Eastern Europe as compared with Western Europe. It has been suggested that a reduced microbial stimulation during infancy and early childhood would result in a slower postnatal maturation of the immune system and development of an optimal balance between TH1- and TH2-like immunity. AIMS: To test the hypothesis that allergic disease among children may be associated with differences in their intestinal microflora in two countries with a low (Estonia) and a high (Sweden) prevalence of allergy. METHODS: From a prospective study of the development of allergy in relation to environmental factors, 29 Estonian and 33 Swedish 2-year-old children were selected. They were either nonallergic (n = 36) or had a confirmed diagnosis of allergy (n = 27) as verified by typical history and at least one positive skin prick test to egg or cow's milk. Weighed samples of faeces were serially diluted (10-2-10-9) and grown under anaerobic conditions. The counts of the various genera and species were calculated for each child. In addition, the relative amounts of the particular microbes were expressed as a proportion of the total count. RESULTS: The allergic children in Estonia and Sweden were less often colonized with lactobacilli (P < 0.01), as compared with the nonallergic children in the two countries. In contrast, the allergic children harboured higher counts of aerobic micro-organisms (P < 0. 05), particularly coliforms (P < 0.01) and Staphylococcus aureus (P < 0.05). The proportions of aerobic bacteria of the intestinal flora were also higher in the allergic children (P < 0.05), while the opposite was true for anaerobes (P < 0.05). Similarly, in the allergic children the proportions of coliforms were higher (P < 0. 05) and bacteroides lower (P < 0.05) than in the nonallergic children. CONCLUSIONS: Differences in the indigenous intestinal flora might affect the development and priming of the immune system in early childhood, similar to what has been shown in rodents. The role of intestinal microflora in relation to the development of infant immunity and the possible consequences for allergic diseases later in life requires further study, particularly as it would be readily available for intervention as a means for primary prevention of allergy by the administration of probiotic bacteria.     

乳酸菌对肠粘膜通透性及中小分子尿毒素清除的影响

目的研究乳酸菌对慢性肾衰竭大鼠的肠粘膜通透性及中小分子尿毒素清除的影响。方法40只SD大鼠分为正常对照组（10只）行假手术,30只作5/6肾切除后分为肾衰竭病理对照组、双歧杆菌治疗组和乳酸杆菌治疗组。喂养1周后处死动物留取血粪标本。用紫外线吸收法测定血/粪中分子物质（MMS）。尿素（UN）和肌酐（Cr）;用酶偶联紫外分光度法检测血D-乳酸。结果病理对照组血、粪MMS和UN、Cr均升高（P〈0.01）;血浆D-乳酸含量增高（P〈0.01）。双歧杆菌治疗组和乳酸杆菌治疗组较病理对照组的血浆D-乳酸含量降低（P〈0.01）;BUN、SCr均降低（P〈0.01）;而粪UN、Cr均增加（P〈0.01）。结论双歧杆菌和乳酸杆菌均可维持慢性肾衰竭大鼠肠粘膜正常通透性,加速肠道清除MMS,分解肠道内尿素和肌酐降低其血中的浓度。     

Safety evaluation of Lactobacillus pentosus strain b240

Lactobacillus pentosus has a long history of use in cooked and uncooked fermented foods. Viable and heat-killed nonviable preparations of L. pentosus strain b240 were evaluated for short term and subchronic toxicity and genotoxic potential. Dose levels were determined through acute oral toxicity tests with viable (LD₅₀ > 2500 mg/kg) and nonviable (LD₅₀ > 2000 mg/kg) b240. In the short term study, rats received 2500 mg/kg/day (∼1.7 × 10¹¹ cfu/kg/day) viable b240 for 28 days. In the subchronic study, rats received 500, 1000 or 2000 mg/kg/day (up to ∼3.0 × 10¹² cfu equivalents/kg/day) nonviable b240 for 91 days followed by a 28-day recovery. No mortalities occurred. No treatment-related effects were identified for general condition, body weight, food-water consumption, ophthalmology, urinalysis, hematology, blood chemistry, organ weights, histopathology and gross pathology. Although statistically significant effects were noted for several endpoints in the short term and subchronic studies, none were related to the test materials. The NOAEL for nonviable b240 was 2000 mg/kg/day, the highest dose tested. Additionally, nonviable b240 (?5000 μg/plate) was not mutagenic in Salmonella typhimurium or Escherichia coli tester strains nor did nonviable b240 orally administered to rats at levels ? 2000 mg/kg/day for two days, induce a clastogenic response.     

高效表达幽门螺杆菌黏附素Hp0410的嗜酸乳杆菌重组菌株的构建

目的构建高效表达幽门螺杆菌黏附素Hp0410的嗜酸乳杆菌重组菌株。方法从幽门螺杆菌标准株NCTC11639中扩增出幽门螺杆菌黏附素基因Hp0410,克隆入穿梭质粒pMG36e中,通过电穿孔将重组质粒转入嗜酸乳杆菌,表达的目的蛋白经SDS聚丙烯酰胺凝胶电泳与硝酸银染色及Western blotting鉴定,并检测重组质粒的稳定性。结果扩增的黏附素Hp0410基因与基因库公布的一致,构建的重组质粒成功转入嗜酸乳杆菌中,表达出分子量约34kD的目的蛋白,Western blotting证实该蛋白可被幽门螺杆菌感染患者血清所识别。重组质粒pMG36e-Hp0410在含有红霉素和不含有红霉素的环境下均稳定。结论成功构建了高效组成型表达幽门螺杆菌黏附素Hp0410的重组嗜酸乳杆菌菌株。     

鼠李糖乳杆菌对感染人轮状病毒乳鼠空肠黏膜上皮细胞的保护作用

目的观察鼠李糖乳杆菌(Lactobacillus rhamnosus GG,LGG)对感染人轮状病毒(human rotavirus,HRV)乳鼠空肠黏膜上皮细胞的保护作用。方法将60只昆明种乳鼠均分为4组:灌服HRV作为感染组;灌服HRV前和后灌服LGG作为预处理组和治疗组;正常对照组灌服细胞培养液。从第4天开始,连续5d观察各组乳鼠的临床症状,每天2次检测乳鼠大便HRV抗原。在实验的第9天随机处死每组中的8只乳鼠,取出空肠段苏木精-伊红染色,利用Image-Pro Plus 5.1图像软件分析各组乳鼠空肠黏膜厚度、绒毛高度和隐窝深度。利用光学显微镜和透射电子显微镜观察乳鼠空肠黏膜上皮细胞的病理变化。结果至第9天,对照组乳鼠无腹泻、无死亡。HRV感染组、预处理组、治疗组乳鼠腹泻率和死亡率分别为100.00%、46.67%,13.33%、0%,26.66%、6.67%。对照组、HRV感染组、预处理组、治疗组乳鼠空肠黏膜隐窝深度分别为(35.2±2.4)、(45.9±3.6)、(35.8±5.6)和(38.9±2.9)μm,HRV感染组明显高于其它3组(均P<0.01)。病理检测发现HRV感染组乳鼠空肠黏膜上皮细胞出现广泛的空泡样变性,而预处理组和治疗组乳鼠空肠黏膜上皮细胞空泡样变性的情况均有减少。预处理组与治疗组相比,前者对乳鼠空肠黏膜上皮细胞的保护效果更好。结论 LGG对感染HRV的乳鼠空肠黏膜上皮细胞有一定的保护作用,感染前灌服LGG的保护效果好于感染后灌服。     

金双歧、蒙脱石散联合儿宝颗粒治疗婴幼儿腹泻疗效观察

目的:探讨金双歧、蒙脱石散联合儿宝颗粒治疗婴幼儿腹泻的临床疗效和安全性。方法:将50例患儿随机分为2组,对照组口服金双歧及蒙脱石散,治疗组在对照组治疗基础上加用儿宝颗粒。结果:对照组总有效率68.18%,治疗组总有效率92.86%,2组比较差异有统计意义(P0.05),且治疗期间均无任何不良反应。结论:金双歧、蒙脱石散联合儿宝颗粒治疗婴幼儿腹泻能提高临床治愈率,且安全,无不良反应。