Impact of a multistrain probiotic formulation with high bifidobacterial content on the fecal bacterial community and short-chain fatty acid levels of healthy adults

The consumption of probiotic products is continually increasing, supported by growing scientific evidence of their efficacy. Considering that probiotics may primarily affect health (either positively or negatively) through gut microbiota modulation, the first aspect that should be evaluated is their impact on the intestinal microbial ecosystem. In this study, we longitudinally analyzed the bacterial taxonomic composition and organic acid levels in four fecal samples collected over the course of four weeks from 19 healthy adults who ingested one capsule a day for two weeks of a formulation containing at least 70 billion colony-forming units, consisting of 25% lactobacilli and 75% Bifidobacterium animalis subsp. lactis. We found that 16S rRNA gene profiling showed that probiotic intake only induced an increase in a single operational taxonomic unit ascribed to B. animalis, plausibly corresponding to the ingested bifidobacterial strain. Furthermore, liquid chromatography/mass spectrometry revealed a significant increase in the lactate and acetate/butyrate ratio and a trend toward a decrease in succinate following probiotic administration. The presented results indicate that the investigated probiotic formulation did not alter the intestinal bacterial ecosystem of healthy adults and suggest its potential ability to promote colonization resistance in the gut through a transient increase in fecal bifidobacteria, lactic acid, and the acetate/butyrate ratio

Risk factors and consequent outcomes of placenta previa: Report from a referral center

Because of an unknown factor, the frequency of complicated pregnancy with placenta previa has been raised during past decade. This study was designed to deepen our understanding of risk factors and outcomes of placenta previa in our country. This study investigated 694 cases of placenta previa comparing with 600 healthy pregnant women with not overlie placenta in two referral and tertiary Obstetrics and Gynecological Hospital in Iran on the basis of the clinical and para-clinical analysis, in order to find the probable risk factors for occurrence of placenta previa and its effect on maternal and neonatal complications. The most important risk factor for the occurrence of placenta previa was advanced maternal age (P<0.001) and history of stillbirth (OR=117.2, CI=58.3-236.0). In the other hand, the most substantial outcome of this disorder was a reduction of gestational age (P<0.001) and low birth weight neonatally (P<0.001). The conservative follow-up should be programmed for women with placenta previa based on the type of risk factors which can provide the best possible management to decrease the morbidity and mortality of their related complications. © 2016 Tehran University of Medical Sciences. All rights reserved

Statistical approach to identify the discharge source in MV cables and accessories

Partial discharge (PD) analysis is a reliable tool to assess the integrity of electrical insulation. Representation and interpretation of the data, obtained from e.g. online PD monitoring, are key issues to reveal the discharge source, i.e. defect type, as well as the physical phenomena behind the occurrence. Analyses of various PD patterns such as discharge height distribution presented in this work provide useful statistical parameters to identify the discharge source. Research shows that the 2-parameter Weibull distribution is a reliable model to quantify the characteristics of the patterns of the defect. The model fits well to the charge-height distribution. In addition, trends in the discharge density pattern that occur over long times, can be used as complementary information to discover the discharge nature. It alerts for a possible failure and therefore assists in taking corrective measures to prevent failure. This paper presents the application of such statistical modeling to the area of on-line power cable diagnostics. Data obtained from laboratory experiments as well as field data have been studied

Characterization of airborne viromes in cheese production plants

Aims To characterize airborne virus like particles isolated from two cheese production plants in order to reveal their complexity in terms of viral communities and microbial genes potentially mobilized by viruses. Methods and results Airborne virus like particles have been isolated from Grana Padano and Gorgonzola PDO cheese production plants and ripening cellars. A shotgun metagenomics analysis of the isolated viromes highlighted a high complexity of the viral communities both in terms of viral taxonomy and phage\u2010host associations. Bacterial reads in each of the viromes were confirmed to be abundant and their taxonomy appeared to be associated to the environmental parameters and the technological processes that characterize the sampling area. Antibiotic resistance genes have been identified in each virome thus confirming that phages could be involved in the mobilization of antimicrobial resistances among bacterial populations. Interestingly human viruses were also identified even if the contamination source was not revealed. Conclusions The environmental conditions, which are imposed by the technology of the dairy process, seams to shape the viral populations as a consequence of the adaptation of microbial taxa to those environments. The identification of sequences belonging to Legionella pneumophila and to the human papillomavirus, raised some considerations about the safety of cheese ripening cellars. Significance and impact of the study In conclusion, the analysis of the dairy airborne viromes, has revealed a high complexity of the viral communities even if the environments where the samples were collected were confined environments. Metagenomics of airborne viral population could be a promising monitoring tool for the biological characterization of dairy environments

Effect of oral consumption of capsules containing Lactobacillus paracasei LPC-S01 on the vaginal microbiota of healthy adult women: a randomized, placebo-controlled, double-blind crossover study

Oral consumption of probiotics is practical and can be an effective solution to preserve vaginal eubiosis. Here, we studied the ability of orally administered Lactobacillus paracasei LPC-S01 (DSM 26760) to affect the composition of the vaginal microbiota and colonize the vaginal mucosa in nondiseased adult women. A total of 40 volunteers took oral probiotic (24 billion CFU) or placebo capsules daily for 4 weeks, and after a 4-week washout, they switched to placebo or probiotic capsules according to the crossover design. A total of 23 volunteers completed the study according to the protocol. Before and after capsule ingestion, vaginal swabs were collected for qPCR quantification to detect L. paracasei LPC-S01 and for 16S rRNA gene sequencing. Vaginal swabs were grouped according to their bacterial taxonomic structure into nine community state types (CSTs), four of which were dominated by lactobacilli. Lactobacillus paracasei LPC-S01 was detected in the vagina of two participants. Statistical modeling (including linear mixed-effects model analysis) demonstrated that daily intake of probiotic capsules reduced the relative abundance of Gardnerella spp. Quantitative PCR with Gardnerella vaginalis primers confirmed this result. Considering the pathogenic nature of G. vaginalis, these results suggest a potential positive effect of this probiotic capsule on the vaginal microbial ecosystem

Evidence of dysbiosis in the intestinal microbial ecosystem of children and adolescents with primary hyperlipidemia and the potential role of regular hazelnut intake

Hyperlipidemia starts at a pediatric age and represents an unquestionable risk factor for cardiovascular disease. Modulation of the intestinal microbial ecosystem (IME), in principle, can ameliorate lipid profiles. In this study, we characterized the IME of children and adolescents with primary hyperlipidemia by analyzing fecal samples through 16S rRNA gene profiling (n\ua0=\ua015) and short chain fatty acid (SCFA) quantification (n\ua0=\ua032). The same analyses were also carried out on age-matched normolipidemic controls (n\ua0=\ua015). Moreover, we evaluated the modulatory effect of regular hazelnut intake (approximately 0.43 g of hazelnuts with skin per kg of body weight) on the IME of 15 children and adolescents with hyperlipidemia for eight weeks. We found alterations of numerous operational taxonomic units potentially associated with SCFA-producing bacteria and reductions in the fecal levels of acetate, butyrate and propionate in hyperlipidemic subjects. Furthermore, we observed that an eight-week hazelnut intervention may induce limited changes in fecal microbiota composition but can significantly modulate the fecal levels of predominant intestinal SCFAs, such as acetate. Finally, correlation analyses indicated that changes in lipidemic parameters are linked to modifications of the abundance of specific bacterial taxa, such as the families Lachnospiraceae and Ruminococcaceae and the genera Akkermansia, Bacteroides, Roseburia, and Faecalibacterium. This study suggests that children and adolescents with primary hyperlipidemia possess an altered IME. The promising results presented here support the need for future dietary interventions aimed at positively modulating the IME of hyperlipidemic subjects

Enrichment of intestinal Lactobacillus by enhanced secretory IgA coating alters glucose homeostasis in P2rx7 &#8722;/&#8722; mice

The secretory immunoglobulin A (SIgA) in mammalian gut protects the organism from infections and contributes to host physiology by shaping microbiota composition. The mechanisms regulating the adaptive SIgA response towards gut microbes are poorly defined. Deletion of P2rx7, encoding for the ATP-gated ionotropic P2X7 receptor, leads to T follicular helper (Tfh) cells expansion in the Peyer\u2019s patches (PPs) of the small intestine, enhanced germinal centre (GC) reaction and IgA secretion; the resulting alterations of the gut microbiota in turn affects host metabolism. Here, we define gut microbiota modifications that correlate with deregulated SIgA secretion and metabolic alterations in P2rx7 12/ 12 mice. In particular, Lactobacillus shows enhanced SIgA coating in P2rx7 12/ 12 with respect to wild-type (WT) mice. The abundance of SIgA-coated lactobacilli positively correlates with Tfh cells number and body weight, suggesting Lactobacillus-specific SIgA response conditions host metabolism. Accordingly, oral administration of intestinal Lactobacillus isolates from P2rx7 12/ 12 mice to WT animals results in altered glucose homeostasis and fat deposition. Thus, enhanced SIgA production by P2X7 insufficiency promotes Lactobacillus colonization that interferes with systemic metabolic homeostasis. These data indicate that P2X7 receptor-mediated regulation of commensals coating by SIgA is important in tuning the selection of bacterial taxa, which condition host metabolism

Surface Layer of Lactobacillus helveticus MIMLh5 Promotes Endocytosis by Dendritic Cells

Surface layers (S-layers) are proteinaceous arrays covering the cell walls of numerous bacteria. Their suggested properties, such as interactions with the host immune system, have been only poorly described. Here, we aimed to elucidate the role of the S-layer from the probiotic bacterial strain Lactobacillus helveticus MIMLh5 in the stimulation of murine bone-marrow-derived dendritic cells (DCs). MIMLh5 induced greater production of interferon beta (IFN-\u3b2), interleukin 10 (IL-10), and IL-12p70, compared to S-layer-depleted MIMLh5 (naked MIMLh5 [n-MIMLh5]), whereas the isolated S-layer was a poor immunostimulator. No differences in the production of tumor necrosis factor alpha (TNF-\u3b1) or IL-1\u3b2 were found. Inhibition of the mitogen-activated protein kinases JNK1/2, p38, and ERK1/2 modified IL-12p70 production similarly in MIMLh5 and n-MIMLh5, suggesting the induction of the same signaling pathways by the two bacterial preparations. Treatment of DCs with cytochalasin D to inhibit endocytosis before the addition of fluorescently labeled MIMLh5 cells led to a dramatic reduction in the proportion of fluorescence-positive DCs and decreased IL-12 production. Endocytosis and IL-12 production were only marginally affected by cytochalasin D pretreatment when fluorescently labeled n-MIMLh5 was used. Treatment of DCs with fluorescently labeled S-layer-coated polystyrene beads (Sl-beads) resulted in much greater uptake of beads, compared to noncoated beads. Prestimulation of DCs with cytochalasin D reduced the uptake of Sl-beads more than plain beads. These findings indicate that the S-layer plays a role in the endocytosis of MIMLh5 by DCs. In conclusion, this study provides evidence that the S-layer of L. helveticus MIMLh5 is involved in endocytosis of the bacterium, which is important for strong Th1-inducing cytokine production.IMPORTANCE Beneficial microbes may positively affect host physiology at various levels, e.g., by participating in immune system maturation and modulation, boosting defenses and dampening reactions, thus affecting the whole homeostasis. As a consequence, the use of probiotics is increasingly regarded as suitable for more extended applications for health maintenance, not only microbiota balancing. This implies a deep knowledge of the mechanisms and molecules involved in host-microbe interactions, for the final purpose of fine tuning the choice of a probiotic strain for a specific outcome. With this aim, studies targeted to the description of strain-related immunomodulatory effects and the identification of bacterial molecules responsible for specific responses are indispensable. This study provides new insights in the characterization of the food-origin probiotic bacterium L. helveticus MIMLh5 and its S-layer protein as a driver for the cross-talk with DCs

Viromes as genetic reservoir for the microbial communities in aquatic environments : a focus on antimicrobial-resistance genes

Despite studies of viromes isolated from aquatic environments are becoming increasingly frequent, most of them are limited to the characterization of viral taxonomy. Bacterial reads in viromes are abundant but the extent to which this genetic material is playing a role in the ecology of aquatic microbiology remains unclear. To this aim, we developed of a useful approach for the characterization of viral and microbial communities of aquatic environments with a particular focus on the identification of microbial genes harbored in the viromes. Virus-like particles were isolated from water samples collected across the Lambro River, from the spring to the high urbanized Milan area. The derived viromes were analyzed by shotgun metagenomic sequencing looking for the presence, relative abundance of bacterial genes with particular focus on those genes involved in antimicrobial resistance mechanisms. Antibiotic and heavy metal resistance genes have been identified in all virome samples together with a high abundance of reads assigned to cellular processes and signaling. Virome data compared to those identified in the microbiome isolated from the same sample revealed differences in terms of functional categories and their relative abundance. To verify the role of aquatic viral population in bacterial gene transfer, water-based mesocosms were perturbed or not perturbed with a low dose of tetracycline. The results obtained by qPCR assays revealed variation in abundance of tet genes in the virome and microbiome highlighting a relevant role of viral populations in microbial gene mobilization