Presence of Bacillus coagulans spores and vegetative cells in rat intestine and feces and their physiological effects

ABSTRACT

This study was aimed to investigate the presence of Bacillus coagulans vegetative cells in the intestine and fecal samples in rats fed B. coagulans spores as well as to estimate the ratios of spores and vegetative cells in these samples. A two-step process has been developed to enumerate B. coagulans in different mixed bacterial samples, specifically (1) observation of yellow ring formation on modified GYEA medium upon incubation at 55°C, (2) microscopic examination of spore formation after 7 d of incubation. Our results have demonstrated the presence of vegetative cells in the intestinal and fecal samples in rats fed B. coagulans spores. The ratios of B. coagulans spores and vegetative cells in cecal fluid, colonic content, and feces were approximately 2:8, 2:8, and 4:6, respectively. The existence of B. coagulans vegetative cells improved the intestinal milieu through an elevated short-chain fatty acid concentrations, higher fecal moisture, and lower fecal pH.     

Saikosaponin-d,a novel SERCA inhibitor,induces autophagic cell death in apoptosis-defective cells

Autophagy is an important cellular process that controls cells in a normal homeostatic state by recycling nutrients to maintain cellular energy levels for cell survival via the turnover of proteins and damaged organelles. However, persistent activation of autophagy can lead to excessive depletion of cellular organelles and essential proteins, leading to caspase-independent autophagic cell death. As such, inducing cell death through this autophagic mechanism could be an alternative approach to the treatment of cancers. Recently, we have identified a novel autophagic inducer, saikosaponin-d (Ssd), from a medicinal plant that induces autophagy in various types of cancer cells through the formation of autophagosomes as measured by GFP-LC3 puncta formation. By computational virtual docking analysis, biochemical assays and advanced live-cell imaging techniques, Ssd was shown to increase cytosolic calcium level via direct inhibition of sarcoplasmic/endoplasmic reticulum Ca²⁺ ATPase pump, leading to autophagy induction through the activation of the Ca²⁺/calmodulin-dependent kinase kinase–AMP-activated protein kinase–mammalian target of rapamycin pathway. In addition, Ssd treatment causes the disruption of calcium homeostasis, which induces endoplasmic reticulum stress as well as the unfolded protein responses pathway. Ssd also proved to be a potent cytotoxic agent in apoptosis-defective or apoptosis-resistant mouse embryonic fibroblast cells, which either lack caspases 3, 7 or 8 or had the Bax-Bak double knockout. These results provide a detailed understanding of the mechanism of action of Ssd, as a novel autophagic inducer, which has the potential of being developed into an anti-cancer agent for targeting apoptosis-resistant cancer cells.     

Associations between Extending Access to Primary Care and Emergency Department Visits: A Difference-In-Differences Analysis

BackgroundHealth services across the world increasingly face pressures on the use of expensive hospital services. Better organisation and delivery of primary care has the potential to manage demand and reduce costs for hospital services, but routine primary care services are not open during evenings and weekends.Extended access (evening and weekend opening) is hypothesized to reduce pressure on hospital services from emergency department visits. However, the existing evidence-base is weak, largely focused on emergency out-of-hours services, and analysed using a before-and after-methodology without effective comparators.ConclusionsThe study found that extending access was associated with a reduction in emergency department visits in the first 12 months. The results of the research have already informed the decision by National Health Service England to extend primary care access across Greater Manchester from 2016. However, further evidence is needed to understand whether extending primary care access is cost-effective and sustainable.     

Decoupled genomic elements and the evolution of partner quality in nitrogen‐fixing rhizobia

Understanding how mutualisms evolve in response to a changing environment will be critical for predicting the long‐term impacts of global changes, such as increased N (nitrogen) deposition. Bacterial mutualists in particular might evolve quickly, thanks to short generation times and the potential for independent evolution of plasmids through recombination and/or HGT (horizontal gene transfer). In a previous work using the legume/rhizobia mutualism, we demonstrated that long‐term nitrogen fertilization caused the evolution of less‐mutualistic rhizobia. Here, we use our 63 previously isolated rhizobium strains in comparative phylogenetic and quantitative genetic analyses to determine the degree to which variation in partner quality is attributable to phylogenetic relationships among strains versus recent genetic changes in response to N fertilization. We find evidence of distinct evolutionary relationships between chromosomal and pSym genes, and broad similarity between pSym genes. We also find that nifD has a unique evolutionary history that explains much of the variation in partner quality, and suggest MoFe subunit interaction sites in the evolution of less‐mutualistic rhizobia. These results provide insight into the mechanisms behind the evolutionary response of rhizobia to long‐term N fertilization, and we discuss the implications of our results for the evolution of the mutualism.     

Acceptability of Voluntary Medical Male Circumcision (VMMC) among Male Sexually Transmitted Diseases Patients (MSTDP) in China

Voluntary Medical Male circumcision (VMMC) is an evidence-based, yet under-utilized biomedical HIV intervention in China. No study has investigated acceptability of VMMC among male sexually transmitted diseases patients (MSTDP) who are at high risk of HIV transmission. A cross-sectional survey interviewed 350 HIV negative heterosexual MSTDP in Shenzhen, China; 12.0% (n = 42) of them were circumcised at the time of survey. When the uncircumcised participants (n = 308) were informed that VMMC could reduce the risk of HIV infection via heterosexual intercourse by 50%, the prevalence of acceptability of VMMC in the next six months was 46.1%. Adjusted for significant background variables, significant factors of acceptability of VMMC included: 1) emotional variables: the Emotional Representation Subscale (adjusted odds ratios, AOR = 1.13, 95%CI: 1.06–1.18), 2) cognitive variables derived from Health Belief Model (HBM): perceived some chance of having sex with HIV positive women in the next 12 months (AOR = 2.48, 95%CI: 1.15–5.33) (perceived susceptibility), perceived severity of STD infection (AOR = 1.06, 95%CI: 1.02–1.10), perceived benefit of VMMC in risk reduction (AOR = 1.29, 95%CI: 1.16–1.42) and sexual performance (AOR = 1.45, 95%CI: 1.26–1.71), perceived barriers against taking up VMMC (AOR = 0.88, 95%CI: 0.81–0.95), and perceived cue to action (AOR = 1.41, 95%CI: 1.23–1.61) and self-efficacy (AOR = 1.38, 95%CI: 1.26–1.35) related to taking up VMMC. The association between perceived severity of STD infection and acceptability was fully mediated by emotional representation of STD infection. The relatively low prevalence of circumcision and high acceptability suggested that the situation was favorable for implementing VMMC as a means of HIV intervention among MSTDP in China. HBM is a potential suitable framework to guide the design of future VMMC promotion. Future implementation programs should be conducted in STD clinic settings, taking the important findings of this study into account.