Signals triggering prophage induction in the gut microbiota.

Compared to bacteria of the gut microbiota, bacteriophages are still poorly characterised, and their physiological importance is far less known. Temperate phages are probably a major actor in the gut, as it is estimated that 80% of intestinal bacteria are lysogens, meaning that they are carrying prophages. In addition, prophage induction rates are higher in the gut than in vitro. However, studies on the signals leading to prophage induction have essentially focused on genotoxic agents with poor relevance for this environment. In this review, we sum up recent findings about signals able to trigger prophage induction in the gut. Three categories of signals are at play: those originating from interactions between intestinal microbes, those from the human or animal host physiology and those from external intakes. These recent results highlight the diversity of factors influencing prophage induction in the gut, and start to unveil ways by which microbiota composition may be modulated.

Citrus limon phytocompounds decorated nanoparticles control poultry pathogens.

Antibiotic resistance poses a significant threat to the global health, food security, and environment. In poultry and livestock, antibiotics are beneficial since they improve poultry performance and are economically effective. Therefore, it is crucial to search for alternatives that can be environmentally safe and successful in treating these infections. In this study, we employed molecular docking to evaluate lemon peel phytochemical's protein binding capability against various poultry pathogens. The nanoparticles (LP AgNPs) obtained from the lemon peel were characterized and tested for their antibacterial activity against more poultry pathogens. LP AgNPs were characterized by using UV-Visible absorption spectra, which revealed an absorption peak at a wavelength of 420-440 nm. The FT-IR analysis demonstrated that flavonoids and phenolic acids acted as capping, reducing, and stabilizing agents during the biosynthesis of AgNPs. EDAX showed a strong peak was observed at 3 keV which revealed the absorption of metallic silver nanoparticles. The mean diameter was from 2 to 20 nm through HRTEM. Zeta potential of the LP AgNps at - 17.2 mV showed the high stability of the green synthesized AgNps. Maximum inhibitory concentrations of LP AgNps against the isolated poultry pathogens were 50 µg/ml concentration. The toxicity tests were performed in the Vigna radiata seedlings and Artemia nauplii, which showed less toxic effects and eco-friendly nature of the LP AgNps. LP AgNps have the potential to treat antibiotic resistant poultry pathogens, thereby paving the way for the development of value-added novel products incorporated with nanoparticles for treating various infection caused by antibiotic-resistant poultry pathogens.

Maribacter litopenaei sp. nov., isolated from the intestinal tract of the Pacific white shrimp Litopenaeus vannamei.

A Gram-stain-negative, aerobic, rod-shaped bacterial strain, designated HL-LV01T, was isolated from the intestinal tract content of the Pacific white shrimp Litopenaeus vannamei. The 16S rRNA gene sequence of strain HL-LV01T showed that the strain was clearly a member of the genus Maribacter. According to the phylogenetic analyses, strain HL-LV01T was most closely related to the species Maribacter flavus KCTC 42508T with 98.2 % sequence similarity. The average nucleotide identity and digital DNA-DNA hybridization values between strain HL-LV01T and M. flavus KCTC 42508T were 80.6 % and 23.0 %, respectively, indicating different genomic species in the genus Maribacter. Strain HL-LV01T showed optimal growth at 35 °C, pH 7.0, and 2.5 % (w/v) sea salts. The major cellular fatty acids were iso-C15 : 0 (32.5 %), iso-C17 : 0 3-OH (22.3 %), and iso-C15 : 1 G (15.5 %). The major respiratory quinone was menaquinone-6. The polar lipids consisted of phosphatidylethanolamine, three unidentified aminolipids, and seven unidentified lipids. The genomic DNA G+C content of the strain was 39.8 mol%. The comprehensive phylogenetic, genomic, phenotypic, and chemotaxonomic results indicate that strain HL-LV01T is distinct from validly published species of the genus Maribacter. Hence, we propose strain HL-LV01T as a novel species belonging to the genus Maribacter, for which the name Maribacter litopenaei sp. nov. is proposed. The type strain is HL-LV01T (= KCCM 90498T = JCM 35709T).

Effect of magnetized water on blood indices and histomorphometric parameters of intestinal sections of Japanese quail.

A two-way experimental design was used to demonstrate the physiological effects of magnetized water and sex on blood indices and histomorphometric parameters of Japanese quail intestine sections. Red blood cell count (RBCs), packed cell volume (PCV), hemoglobin concentration (Hb), thrombocytes, white blood cell count (WBCs), and WBC differentiation were investigated. A total of 450 unsexed Japanese quail were randomized into three groups (45/replicate; 3 replicates; 135/group). As a monitoring group, the first group was given untreated tap water to drink. The two others were consumed magnetized water that were subjected to an electrical magnetic field with a power of 1 Tesla (10,000 Gauss) and 2 Tesla (20,000 Gauss), respectively. The treatments had a significant (p ≤ 0.05) effect on thrombocytes and Hb. Sex showed significant (p ≤ 0.05) differences for RBCs and PCV at 42 days of age. At different ages, significant effects were observed on histomorphometric parameters of the Japanese quail intestinal tract. It may be inferred that the influence of magnetized water, up to 1 Tesla, was positive on the haematological and histomorphometric parameters of the Japanese quail intestinal tract by augmenting the haematological measurements, which were within a normal range and increasing the surface area of the villus.

The potential role of molecular mimicry by the anaerobic microbiota in the aetiology of autoimmune disease.

Autoimmune diseases are thought to develop as a consequence of various environmental and genetic factors, each of which contributes to dysfunctional immune responses and/or a breakdown in immunological tolerance towards native structures. Molecular mimicry by microbial components is among the environmental factors thought to promote a breakdown in immune tolerance, particularly through the presence of cross-reactive epitopes shared with the human host. While resident members of the microbiota are essential promoters of human health through immunomodulation, defence against pathogenic colonisation and conversion of dietary fibre into nutritional resources for host tissues, there may be an underappreciated role of these microbes in the aetiology and/or progression of autoimmune disease. An increasing number of molecular mimics are being identified amongst the anaerobic microbiota which structurally resemble endogenous components and, in some cases, for example the human ubiquitin mimic of Bacteroides fragilis and DNA methyltransferase of Roseburia intestinalis, have been associated with promoting antibody profiles characteristic of autoimmune diseases. The persistent exposure of molecular mimics from the microbiota to the human immune system is likely to be involved in autoantibody production that contributes to the pathologies associated with immune-mediated inflammatory disorders. Here-in, examples of molecular mimics that have been identified among resident members of the human microbiota and their ability to induce autoimmune disease through cross-reactive autoantibody production are discussed. Improved awareness of the molecular mimics that exist among human colonisers will help elucidate the mechanisms involved in the breakdown of immune tolerance that ultimately lead to chronic inflammation and downstream disease.

Comparison study of protective effects of porcine bile acids and sheep bile acids against heat stress in chickens.

BACKGROUND: Heat stress (HS) is known to exert negative effects on the poultry and breeding industry, resulting in severe economic losses. Bile acids (BAs), an important component of bile, play a crucial role in improving the production performance of livestock and poultry, alleviating stress injury, and ensuring the health of livestock and poultry. At present, porcine BAs are widely used because of their therapeutic effects on HS; however, it remains unclear whether the same effects are exerted by sheep BAs, which are different from porcine BAs and have different compositions. In this study, we compared the anti-HS effects of porcine BAs and sheep BAs in the diet by establishing an HS model of chicks and investigating the chicken performance, HS-related genes' expression, oxidative stress markers, jejunal histoarchitecture, inflammatory cytokines' expression, jejunal secreted immunoglobulin A concentration, and cecal bacterial flora. RESULTS: The results showed that the addition of sheep BAs to the diet increased the average daily weight gain and the feed conversion ratio of chicks. Under HS, sheep BAs were more effective than porcine BAs in improving the activities of lactate dehydrogenase and glutamic pyruvic transaminase in serum and the content/activity of malondialdehyde, superoxide dismutase, and reduced glutathione in serum and tissue, in reducing the messenger RNA (mRNA) expression of heat shock proteins (HSP60, HSP70, and HSP90) in the liver and jejunum, and in improving the histological structure and the expression of tight junction proteins (occludin and zonula occludens-1) and enriching intestinal bacterial flora. However, porcine BAs were significantly inferior to sheep BAs in reducing the mRNA expression of inflammatory factors (interleukin-6, interleukin-1ß, and tumor necrosis factor-α). CONCLUSION: The effect of sheep BAs was more significant than porcine BAs was in alleviating HS injury in chicks, suggesting that sheep BAs have great potential as new feed nutrition and health additive to improve poultry production performance and prevent HS. © 2023 Society of Chemical Industry.

Effects of different dietary protein levels on intestinal aquaporins in weaned piglets.

This study was conducted to investigate the relationship between changes in intestinal aquaporins (AQPs) in piglets fed diets with different protein levels and nutritional diarrhoea in piglets. Briefly, 96 weaned piglets were randomly divided into four groups fed diets with crude protein (CP) levels of 18%, 20%, 22% and 24%. The small intestines and colons of the weaned piglets were collected, and several experiments were conducted. In the small intestine, AQP4 protein expression was higher in weaned piglets fed the higher-CP diets (22% and 24% CP) than in those fed the 20% CP diet except at 72 h (p < 0.01). At 72 h, the AQP4 protein expression in the small intestine was lower in the 18% group than in the other three groups (p < 0.01). Under 20% CP feeding, AQP2, AQP4 and AQP9 protein expression in the colons of piglets peaked at certain time points. The AQP2 and AQP4 mRNA levels in the colon and the AQP4 and AQP4 mRNA levels in the distal colon were approximately consistent with the protein expression levels. However, the AQP9 mRNA content in the colon was highest in the 18% group, and the AQP2 mRNA content in the distal colon was significantly higher in the 24% group than in the 20% group. AQP2 and AQP4 were expressed mainly around columnar cells in the upper part of the smooth colonic intestinal villi, and AQP9 was expressed mainly on columnar cells and goblet cells in the colonic mucosa. In conclusion, 20% CP is beneficial to the normal expression of AQP4 in the small intestine, AQP2, AQP4 and AQP9 in the colon of weaned piglets, which in turn maintains the balance of intestinal water absorption and secretion in piglets.

Dissemination of Leptospira into the intestinal tract resulting in fecal excretion in a hamster model of subcutaneous infection with Leptospirainterrogans.

Leptospirosis, caused by pathogenic Leptospira, is one of the most common zoonotic diseases in the world. It is transmitted to humans through the skin and mucous membranes by contact with water or soil contaminated with urine excreted from infected animals. In human infections, gastrointestinal symptoms such as abdominal pain, vomiting, and diarrhea have been frequently observed, but there have been no reports analyzing gastrointestinal lesions in leptospirosis, and the pathological mechanism of gastrointestinal symptoms in leptospirosis remains unclear. In this study, we investigated the pathological changes and the distribution of leptospires in the intestinal wall, and the presence of leptospires in the intestinal contents and feces, of hamsters subcutaneously infected with Leptospira interrogans. Results showed that infected hamsters had macroscopic redness in the jejunum and ileum. Submucosal hemorrhage was observed histologically, and there was no infiltration of inflammatory cells such as neutrophils. There were no obvious changes in the colon, either macroscopically or histologically, and the feces were normal (solid stools). Leptospira was isolated from all the intestinal walls from the small intestine to the colon, the intestinal contents, and the feces. These findings suggest that the invasion of leptospires into the intestinal wall and the associated submucosal hemorrhage may be the cause of the gastrointestinal symptoms observed in leptospirosis. Furthermore, not only the urine of infected animals but also the feces could be a source of infection.

Ghrelin as a prominent endocrine factor in stress-induced obesity.

Objectives: Ghrelin acts on a variety of central- and peripheral organs causing an orexigenic effect, conclusively followed by increased caloric intake. Recent studies have indicated that ghrelin's function as an orexigenic agent does not entirely reflect the full functional properties of the peptide. Specifically, ghrelin regulates stress-hormone synthesis and secretion therewith affecting the stress-axis. The role of stress in the development of obesity has been extensively studied. However, the orexigenic and underlying stress-regulatory effect of ghrelin has not yet been further considered in the development of stress-induced obesity.Methods: Therefore, this review aims to accentuate the potential of ghrelin as a factor in the pathological development of stress-induced obesity.Results: In this review we discuss (1) the ghrelin-mediated intracellular cascades and elucidate the overall bioactivation of the peptide, and (2) the mechanisms of ghrelin signalling and regulation within the central nervous system and the gastro-intestinal system.Discussion: These biological processes will be ultimately discussed in relation to the pathogenesis of stress-induced obesity.

Factors affecting the fate of ß-carotene in the human gastrointestinal tract: A narrative review.

Carotenoids and their metabolites play crucial roles in human health such as in immunity, cell differentiation, embryonic development, maintenance of plasma membrane integrity, and gastrointestinal functions, in addition to counteracting night blindness and other eye-related diseases. However, carotenoid bioavailability is highly variable and often low. The bioavailability of ß-carotene, among the most frequently consumed carotenoid from the diet, is determined by food matrix related factors such as carotenoid dose, its location in food the matrix, the physical state in food, the presence of other food compounds in the matrix such as dietary fiber, dietary lipids, other micronutrients present such as minerals, and food processing, influencing also the size of food particles, and the presence of absorption inhibitors (fat replacers and anti-obesity drugs) or enhancers (nano-/micro-formulations). However, also host-related factors such as physiochemical interactions by gastrointestinal secretions (enzyme and salts) and other host-related factors such as surgery, age, disease, obesity, and genetic variations have shown to play a role. This review contributes to the knowledge regarding factors affecting the bioavailability of ß-carotene (food and host-relegated), as well as highlights in vitro models employed to evaluate ß-carotene bioavailability aspects.

A guide to oral vaccination: Highlighting electrospraying as a promising manufacturing technique toward a successful oral vaccine development.

Most vaccines approved by regulatory bodies are administered via intramuscular or subcutaneous injections and have shortcomings, such as the risk of needle-associated blood infections, pain and swelling at the injection site. Orally administered vaccines are of interest, as they elicit both systemic and mucosal immunities, in which mucosal immunity would neutralize the mucosa invading pathogen before the onset of an infection. Hence, oral vaccination can eliminate the injection associated adverse effects and enhance the person's compliance. Conventional approaches to manufacturing oral vaccines, such as coacervation, spray drying, and membrane emulsification, tend to alter the structural proteins in vaccines that result from high temperature, organic and toxic solvents during production. Electrohydrodynamic processes, specifically electrospraying, could solve these challenges, as it also modulates antigen release and has a high loading efficiency. This review will highlight the mucosal immunity and biological basis of the gastrointestinal immune system, different oral vaccine delivery approaches, and the application of electrospraying in vaccines development.

[Preliminary study on time-dependent changes of intestinal tract and brain-gut axis in mice model of Parkinson's disease induced by paraquat].

Objective: To observe the intestinal time-dependent changes in Parkinson's disease (PD) mouse model constructed by intraperitoneal injection of paraquat (PQ) and to establish the brain-gut axis connection initially. Methods: In October 2019, 48 mice were randomly divided into treated group and control groups: treated 4-week (P-4) group, treated 6-week (P-6) group, treated 8-week (P-8) group, control 4-week (C-4) group, control 6-week (C-6) group, and control 8-week (C-8) group. The treated group was injected with 15 mg/kg PQ solution and the control group was injected with 0.9% saline (0.2 ml/20 g) by intraperitoneal injection twice a week. After the initial state (0 weeks) and the treatment at the end of 4, 6 and 8 weeks, the mood changes and motor functions of mice were assessed by neurobehavioral tests (open field test, pole climbing test, tail suspension test and elevated plus maze test) . And the number of fecal pellets for 1 h and water content were calculated to assess the functional status of the gastrointestinal tract. Western blotting experiments were performed to detect the expression levels of α-synuclein (α-syn) and tyrosine hydroxylase (TH) in the nigrostriatal region of the mouse brain, the tight junction markers zonula occludens-1 (ZO-1) and Occludin, the inflammatory markers of integrin αM subunit (CD11b) , inducible nitric oxide synthase (iNOS) , high mobility group box 1 (HMGB1) , interleukin-1ß (IL-1ß) , and the neuronal markers ßⅢ-tubulin and α-syn protein in the colon.Immunohistochemical staining was performed to detect the expression levels of colonic tight junction proteins ZO-1 and Occludin. Immunofluorescence staining was performed to detect the expression levels of TH in the substantia nigra region of the midbrain, and the co-localization of colonic intestine neuronal marker (ßⅢ-tubulin) and Ser129 α-syn in the colonic. Results: Compared with the initial state (0 weeks) and C-8 group, mice in the P-8 group had significantly higher pole climbing test scores and resting time, and significantly lower total active distance, mean active speed, percentage of open arm entry and 1 h fecal instances (P<0.05) . After poisoning, the 1 h fecal water content of model mice first increased and then decreased, the P-4 and P-6 groups were significantly higher than the simultaneous point control group, and the P-8 groups were significantly lower than the initial state (P<0.05) . Compared with control, P-4 and P-6 groups, the expression levels of ZO-1 and Occludin in the P-8 group were significantly decreased (P<0.05) . Compared with control group, the expression levels of CD11b and IL-1ß in the P-4 group were significantly increased (P<0.05) . Compared with control and P-4 group, the expression levels of CD11b, iNOS, HMGB1 and IL-1ß in the P-6 and P-8 groups were significantly increased (P<0.05) . Compared with the control and P-4 groups, the expression levels of ßⅢ-tubulin in the colon of mice in the P-8 group were significantly decreased, and the expression levels of α-syn and Ser129 α-syn were significantly increased (P<0.05) . The expression level of Ser129 α-syn in the colon of model mice was negatively correlated with the expression level of ßⅢ-tubulin (r(s)=-0.9149, 95%CI: -0.9771--0.7085, P<0.001) . Ser129 α-syn and ßⅢ-tubulin co-localization in the colonic intermuscular plexus region increased gradually with the time of exposure. Compared with the control, P-4 and P-6 groups, the expression level of TH in the nigrostriatal region of the brain was significantly decreased, and the expression levels of α-syn and Ser129 α-syn were significantly increased in the P-8 group (P<0.05) . Correlation analysis showed that the relative expression level of Ser129 α-syn in the nigrostriatal region of the brain was negatively correlated with the expression level of TH in the model mice (r(s)=-0.9716, 95% CI: -0.9925--0.8953, P<0.001) . Conclusion: The PD mouse model is successfully established by PQ, and the intestinal function of the model mice is reduced in a time-dependent manner. And on this basis, it is preliminary determined that the abnormal aggregation of α-syn may be an important substance connecting the brain-gut axis.

A prospective on multiple biological activities of lactoferrin contributing to piglet welfare.

Piglets, especially weaning piglets, show a lower level of immunity and higher morbidity and mortality, owing to their rapid growth, physiological immaturity, and gradual reduction of maternal antibodies, which seriously affects their growth and thus, value. It is important that piglets adapt to nutrient digestion and absorption and develop sound intestinal function and colonization with gut microbiota as soon as possible during their early life stage. Lactoferrin is a natural glycoprotein polypeptide that is part of the transferrin family. It is widely found in mucosal secretions such as saliva and tears, and most highly in milk and colostrum. As a multifunctional bioactive protein and a recommended food additive, lactoferrin is a potential alternative therapy to antibiotics and health promoting additive for piglet nutrition and development. It is expected that lactoferrin, as a natural food additive, could play an important role in maintaining pig health and development. This review examines the following known beneficial effects of lactoferrin: improves the digestion and capacity for absorption in the intestinal tract; promotes the absorption of iron and reduces the incidence of iron deficiency anemia; regulates intestinal function and helps to balance the microbial biota; and enhances the resistance to disease of the piglets via modulating and enhancing the immune system.

Alleviation effects of Bifidobacterium breve on DSS-induced colitis depends on intestinal tract barrier maintenance and gut microbiota modulation.

PURPOSE: The study aimed to investigate the discrepancy and potential mechanisms of different CLA-producing B. breve on dextran sulphate sodium (DSS)-induced colitis. METHODS: Colitis was induced in C57BL/6 J mice using DSS. Disease activity index (DAI), histopathological changes, epithelial barrier integrity and epithelial apoptosis were determined. Gut microbiota were gauged to evaluate the systemic effects of CLA-producing B. breve. RESULTS: Oral administration of different B. breve showed different effects, in which B. breve M1 and B. breve M2 alleviated the inflammation induced by DSS as well as significantly increased the concentration of mucin2 (MUC2) and goblet cells, but neither B. breve M3 nor B. breve M4 had those protective effects. Meanwhile, B. breve M1 and B. breve M2 treatments significantly up-regulated the tight junction (TJ) proteins and ameliorated the epithelial apoptosis lead by DSS challenge. Moreover, inflammatory cytokines (TNF-α, IL-6) were modulated by B. breve M1 and B. breve M2, neither B. breve M3 nor B. breve M4. Furthermore, B. breve M1 and B. breve M2 reduced the abundance of Bacteroides and increased the abundance of Odoribacter, then rebalanced the damaged gut microbiota. Colonic CLA concentrations in mice fed with B. breve M1, B. breve M2, B. breve M3 and B. breve M4 decreased successively, which showed significant positive correlation with the effectiveness of relieving colitis. CONCLUSIONS: Bifidobacterium breve M1 and B. breve M2 alleviated DSS-induced colitis by producing CLA, inhibiting the inflammatory cytokines, maintaining of the intestinal epithelial barrier and regulating the gut microbiota.

Protective effect of Lactobacillus reuteri Lb11 from chicken intestinal tract against Salmonella Enteritidis SE05 in vitro.

Salmonella infections in eggs with increasing morbidity and mortality exhibit worldwide prevalence. The present study intends to evaluate the efficacy of Lactobacillus reuteri Lb11 (L. reuteri Lb11, isolated from chicken intestinal tract) in inhibiting the growth of multi-drug resistant (MDR) Salmonella Enteritidis SE05 (obtained from egg content). The cell-free cell lysates (CFCL) of L. reuteri Lb11 obtained by the agar spot test performed well on inhibition of the MDR (Multi-Drug Resistant) Salmonella Enteritidis SE05, The heat-inactivated (HI) fraction of L. reuteri Lb11 showed no inhibition activity. By co-culturing with L. reuteri Lb11 in vitro, the growth of S. Enteritidis SE05 decreased along with time, while, the pH value decreased significantly. Furthermore, In order to evaluate the mechanism of action of CFCL of L.reuteri Lb11, the genes related to the transcription level of AcrAB-TolC efflux pump, outer membrane protein OMPs genes and drug resistance genes have been quantified by real-time PCR, when the S. Enteritidis was SE05 exposed to the CFCL of L. reuteri Lb11 (1 × 1012 CFU/mL). Almost all of the AcrAB-TolC efflux pump genes, outer membrane protein genes and antibiotic resistance genes were down-regulated. Especially, the level of ramA, tetA and tetB genes were down-regulated -20.77, -15.85 and -12.42 folds, respectively. L. reuteri Lb11 can effectively prevent the formation of efflux pump to inhibit the production of multidrug-resistant Salmonella Enteritidis in eggs.

Janus Kinase Inhibitors Ameliorated Gastrointestinal Amyloidosis and Hypoalbuminemia in Persistent Dermatitis Mouse Model.

Malnutrition is not only regarded as a complication of rheumatoid arthritis and inflammatory bowel disease but also that of inflammatory skin disease; however, the mechanisms and efficacy of its treatment have not been elucidated. Using a mouse model of dermatitis, we investigated the pathophysiology of malnutrition in inflammatory skin conditions and efficacy of its treatment. We employed spontaneous skin inflammation mice models overexpressing human caspase-1 in the epidermal keratinocytes. Body weight, nutrition level, and α1-antitrypsin fecal concentration were measured. The gastrointestinal tract was histologically and functionally investigated. Fluorescein isothiocyanate (FITC)-dextran was forcibly fed on an empty stomach, and plasma FITC-dextran was measured. The treatment efficacy of antibodies against tumor necrosis factor-α (TNF-α) and interleukin (IL)-α/ß as well as Janus kinase (JAK) inhibitors was investigated. Compared with wild-type littermates, the inflammatory skin mice models showed a lowered body weight, reduction of serum albumin level, amyloid deposition in the stomach, small intestine, and large intestine, and increased α1-antitrypsin fecal concentration. However, the plasma FITC-dextran was unchanged between the dermatitis models and wild-type littermates. The over-produced serum amyloid A1 in the liver was detected in the plasma in the dermatitis model. Antibodies against TNF-α and IL-α/ß showed partial effects on amyloid deposition; however, JAK inhibitors improved gastrointestinal amyloidosis with the improvement of skin symptoms. Chronic dermatitis is closely related to secondary amyloidosis in the gastrointestinal tract, resulting in hypoalbuminemia. Therefore, active control of skin inflammation is essential for preventing gastrointestinal complications.

Evaluation of recreational risks due to exposure of antibiotic-resistance bacteria from environmental water: A proposed framework.

This research provides a framework for the human health risk assessment due to exposure of AR (antibiotic resistance) E. coli from recreational water (swimming activity). Literature-based epidemiological studies were used for f-value formulation (i.e., AR E. coli/total number of E. coli isolates) and the theoretical calculation of AR and non-AR E. coli concentrations. Risk was estimated using calculated values by considering four different dose-response (D-R) scenarios with known characteristics due to current lack of availability of D-R for AR bacteria. f-values ranged between 0.14 and 0.59 and the order of calculated theoretical values of maximum AR E. coli are as follows: ampicillin or amoxicillin (38 CFU/dip) > co-trimoxazole (19 CFU/dip) ~ tetracycline (18 CFU/dip) > ceftriaxone or cefotaxime or ceftazidime (10 CFU/dip) ~ ciprofloxacin or ofloxacin (9 CFU/dip). The risk of infection was considerably high for theoretical calculated concentration values regardless of the chosen D-R model (annual risk of infection (95th percentile) = 1, Spearman's rank correlation coefficient = -0.06 to 0.94), under the conditions studied. Further, AR levels of human gastrointestinal-tract were determined using literature-reported data in stool samples and indicated that the resistance level was very high in healthy human (range: 3.7 × 107-8.4 × 107 CFU/g of wet lumen content). The maximum allowable concentration values for AR E. coli and non-ARB (0.0075 CFU/dip and 2.56 CFU/dip) were found to be smaller than the USEPA recreational water quality guidelines (≤126 CFU/100 mL), which can help the USEPA and other regulatory bodies in revisiting the current guidelines. So based on the noted results, we can conclude that the maintenance of inventory of actual measured concentration of ARB in the recreational water sites is needed to prevent unwanted complication related to the treatment of infectious sustained by resistant microbes.

ß-Glucan Extracted from Highland Barley Alleviates Dextran Sulfate Sodium-Induced Ulcerative Colitis in C57BL/6J Mice.

Inflammatory bowel disease (IBD), which significantly affects human health, has two primary presentations: Crohn's disease and ulcerative colitis (UC). Highland barley is the most common food crop for Tibetans and contains much more ß-glucan than any other crop. Highland barley ß-glucan (HBBG) can relieve the gastrointestinal dysfunction and promote intestines health. This study aimed to evaluate whether HBBG can relieve UC in mice. A mouse model of UC was established by adding 2% dextran sulfate sodium (DSS) to drinking water for 1 week. UC was alleviated after the introduction of the HBBG diet, as indicated by reductions in the disease activity index (DAI) score, histopathological damage, and the concentration of colonic myeloperoxidase (MPO), along with an improvement in colonic atrophy. Furthermore, we found that HBBG can increase the relative transcriptional levels of genes encoding ZO-1, claudin-1, occludin, and mucin2 (MUC2), thereby reducing intestinal permeability. Additionally, HBBG maintained the balance of proinflammatory and anti-inflammatory cytokines and modulated the structure of the intestinal flora.

Surgical resection of voluminous epiphrenic diverticula.

A 52-year-old male and 55-year-old female underwent surgical resection of a voluminous symptomatic epiphrenic diverticulum via a right thoracotomy. A formal myotomy of the distal esophagus was not performed. The first patient had an uncomplicated recovery whilst the other patient still suffers from an esophageal-cutaneous fistula and repetitive abscesses, treated by intravenous antibiotics and percutaneous drainage. The authors discuss the indication for resection, surgical techniques and complications.

Nanocrystals for Improving Oral Bioavailability of Drugs: Intestinal Transport Mechanisms and Influencing Factors.

With the limitation of solubility and dissolution rate of insoluble drugs, following oral administration, they would rifely prove poor and volatile bioavailability, which may fail to realize its therapeutic value. The drug nanocrystals are perceived as effective tactic for oral administration of insoluble drugs attributes to possess many prominent properties such as elevating dissolution rate and saturation solubility, high drug loading capacity, and improving oral bioavailability. Based on these advantages, the application of nanocrystals in oral drug delivery has acquired significant achievement, and so far more than 20 products of drug nanocrystals have been confirmed in the market. However, the oral absorption of drug nanocrystals is still facing huge challenges due to the limitation of many factors. Intrinsic properties of the drugs and complex physiological environment of the intestinal tract are the two most important factors affecting the oral bioavailability of drugs. In addition, the research on the multi-aspect mechanisms of nanocrystals promoting gastrointestinal absorption and bioavailability has been gradually deepened. In this review, we summarized recent advances of the nanocrystals delivered orally, and provided an overview to the research progress for crossing the intestinal tract transport mechanisms of the nanocrystals by some new research techniques. Meanwhile, the factors relevant to the transport of drug nanocrystals were also elaborated in detail. Graphical Abstract.