Intestinal epithelial cells apically express glycans, especially α1,2-fucosyl linkages, which work as a biological interface for the host-microbe interaction. Emerging studies have shown that ...epithelial α1,2-fucosylation is regulated by microbes and by group 3 innate lymphoid cells (ILC3s). Dysregulation of the gene (FUT2) encoding fucosyltransferase 2, an enzyme governing epithelial α1,2-fucosylation, is associated with various human disorders, including infection and chronic inflammatory diseases. This suggests a critical role for an interaction between microbes, epithelial cells and ILC3s mediated via glycan residues. In this Review, using α1,2-fucose and Fut2 gene expression as an example, we describe how epithelial glycosylation is controlled by immune cells and luminal microbes. We also address the pathophysiological contribution of epithelial α1,2-fucosylation to pathogenic and commensal microbes as well as the potential of α1,2-fucose and its regulatory pathway as previously unexploited targets in the development of new therapeutic approaches for human diseases.
To estimate the global burden of nontyphoidal Salmonella gastroenteritis, we synthesized existing data from laboratory-based surveillance and special studies, with a hierarchical preference to (1) ...prospective population-based studies, (2) dquo;multiplier studies, dquo; (3) disease notifications, (4) returning traveler data, and (5) extrapolation. We applied incidence estimates to population projections for the 21 Global Burden of Disease regions to calculate regional numbers of cases, which were summed to provide a global number of cases. Uncertainty calculations were performed using Monte Carlo simulation. We estimated that 93.8 million cases (5th to 95th percentile, 61.8–131.6 million) of gastroenteritis due to Salmonella species occur globally each year, with 155,000 deaths (5th to 95th percentile, 39,000–303,000 deaths). Of these, we estimated 80.3 million cases were foodborne. Salmonella infection represents a considerable burden in both developing and developed countries. Efforts to reduce transmission of salmonellae by food and other routes must be implemented on a global scale.
During October-December 2016, the number of norovirus outbreaks in China increased sharply from the same period during the previous 4 years. We identified a recombinant norovirus strain, ...GII.P16-GII.2, as the cause of 44 (79%) of the 56 outbreaks, signaling that this strain could replace the predominant GII.4 viruses.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In 2006, routine immunization of US infants against rotavirus was initiated. We assessed national, regional, and local trends in rotavirus testing and detection before and after vaccine introduction.
...We examined data for July 2000 through June 2008 from a national network of approximately 70 US laboratories to compare geographical and temporal aspects of rotavirus season timing and peak activity. To assess trends in rotavirus testing and detection, we restricted the analyses to 33 laboratories that reported for >or=26 weeks per season from 2000 to 2008.
Nationally, the onset and peak of the 2007-2008 rotavirus season were delayed 15 and 8 weeks, respectively, compared with prevaccine seasons from 2000-2006. Delays were observed in each region. The 2007-2008 rotavirus season lasted 14 weeks compared with a median of 26 weeks during the prevaccine era. Of 33 laboratories, 32 reported fewer positive results and a lower proportion of positive test results in 2007-2008 compared with the median in 2000-2006, with a 67% decline in the number and a 69% decline in the proportion of rotavirus-positive test results. The proportion of positive test results in 2007-2008 compared with the median in 2000-2006 declined >50% in 79% of the laboratories and >75% in 39% of the laboratories.
The 2007-2008 US rotavirus season seems substantially delayed, shorter, and diminished in magnitude compared with seasons before vaccine implementation. The extent of change seems greater than expected on the basis of estimated vaccine coverage, suggesting indirect benefits to unvaccinated individuals. Monitoring in future seasons is needed to confirm these trends.
Recent years have seen extremely fast development of new viral nanovaccines and diagnostic agents using nanostructures prepared by biological and chemical synthesis. We used spherical gold ...nanoparticles (average diameter, 15 nm) as a platform for the antigen for swine transmissible gastroenteritis virus (TGEV). The literature data demonstrate that immunization of animals with the TGEV antigen coupled to gold nanoparticles (GNPs) not only activates antigen-presenting cells but also increases the proliferative activity of splenic lymphoid (antibody-forming) cells. The contents of γ-IFN, IL-1β, and IL-6 in animals immunized with GNP-antigen conjugates were found to be higher than those in intact animals or in animals given the antigen alone. The increased concentration of IL-1β in the immunized animals directly correlated with the activity of macrophages and stimulated B cells, which produce this cytokine when activated. The increased concentration of IL-6 indicates that the injected preparations are stimulatory to cellular immunity. Immunization with the TGEV antigen conjugated to GNPs as a carrier activates the respiratory activity of lymphoid cells and peritoneal macrophages, which is directly related to their transforming activity and to the activation of antibody generation. Furthermore, the use of this conjugate allows marked improvement of the structure of the animals’ immune organs and restores the morphological–functional state of these organs. The microanatomical changes (increased number of follicles) indicate the activation of the B-dependent zone of the spleen and, consequently, the development of a humoral-type immunological reaction. The degradative processes observed in the animals immunized with TGEV antigen alone are evidence of weak resistance to pathogen attack. These results can be used to develop vaccines against this infection by employing TGEV antigen coupled to gold nanoparticles as a carrier.
The intestinal barrier is formed by enterocyte membranes, tight junctions, secreted mucus, and immunologic factors, such as tissue macrophages. Dysfunction of this barrier can be caused by different ...types of stress (e.g., physiological, pathological, psychological, pharmacological) and can lead to increased intestinal permeability. Increased permeability to endotoxin, a component of the walls of gram-negative bacteria, causes local or systemic inflammatory reactions, or both. The immune response(s) can then promote more serious conditions. Exertional heat stroke is an example of such a condition. During severe exercise-heat stress, possibly combined with other stresses, reductions in intestinal blood flow, direct thermal damage to the intestinal mucosa, or both, can cause intestinal barrier disruption and endotoxemia. The resulting inflammatory response is believed to be involved in altered thermoregulation and multiple-organ dysfunction. Possible means for preventing or attenuating, or both, many stress-induced intestinal barrier problems include environmental, pharmaceutical, or nutritional approaches, or a combination of these.
A wide range of enteric pathogens can cause infectious gastroenteritis. Conventional diagnostic algorithms are time-consuming and often lack sensitivity and specificity. Advances in molecular ...technology have provided new clinical diagnostic tools. Multiplex polymerase chain reaction (PCR)-based testing has been used in gastroenterology diagnostics in recent years. This article presents a review of recent laboratory-developed multiplex PCR tests and current commercial multiplex gastrointestinal pathogen tests. It focuses on two commercial syndromic multiplex tests: Luminex xTAG Gastrointestinal Pathogen Panel and BioFire FilmArray gastrointestinal test. Multiplex PCR tests have shown superior sensitivity to conventional methods for detection of most pathogens.
Acute gastroenteritis is a substantial cause of hospitalization in children. Shigella, Salmonella, Campylobacter, Yersinia, enterotoxigenic Escherichia coli (ETEC), Giardia and Cryptosporidium are ...gastrointestinal pathogens that are notifiable in New Zealand (NZ). The impact of these infections in the pediatric population has not yet been analyzed. The aim of this study was to describe the epidemiological trends in disease notifications and hospital admissions due to non-viral gastroenteritis in NZ children.
In this population-based descriptive study, age-specific and age-standardized notification and hospital admission rates were analyzed from 1997-to-2015 for Shigella, Salmonella, Campylobacter, Yersinia, ETEC, Giardia and Cryptosporidium infections in children < 15 years of age. Variations in disease by gender, age, ethnicity and geography were described.
From 1997-to-2015 there were 74,454 notifications (57.6% male) and 3192 hospitalizations (56.4% male) due to non-viral gastroenteritis in NZ children aged < 15 years. There was an overall trend towards a reduction in disease notifications and hospitalizations, however each disease showed a unique pattern of change over time. Campylobacter was the pathogen most frequently notified, accounting for 51.7% of notifications and 43.4% of hospitalizations. The hospitalization-to-notification ratios were, from highest to lowest, Salmonella typhi (1:1.09), Shigella (1:4.0), ETEC (1:7.81), nontyphoidal Salmonella (1:13.1), Campylobacter (1:27.8), Yersinia (1:29.2), Cryptosporidium (1,33.4), and Giardia (1,72.5). Compared to females, male notification rates were approximately 40% higher for Campylobacter, 25% higher for Giardia and Yersinia, and 15% higher for Cryptosporidium and nontyphoidal Salmonella (p < 0.001). Notification rates were highest in children 1-4 years, with the exceptions of nontyphoidal Salmonella, Salmonella typhi and Yersinia. Notification rates for nontyphoidal Salmonella and Yersinia were highest in children < 1 year, and for Salmonella typhi those aged 5-9 years. Children < 1 year were most likely to be hospitalized.
The incidence of non-viral gastroenteritis in NZ children reduced during the 19-year period considered. The burden of disease was highest in the community, with only a small percentage of cases requiring hospitalization. This study provides important insight into the non-viral causes of gastroenteritis in NZ children and how environmental influences and changes in food safety practices may have helped to reduce the burden of these diseases in children.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background. Noroviruses (NoVs) are the most common cause of epidemic gastroenteritis; however, the relative impacts of individual factors underlying severe illness are poorly understood. This report ...reviews published NoV outbreak reports to quantify hospitalization and mortality rates and assess their relationship with outbreak setting, transmission route, and strain. Methods. Using a string of terms related to "norovirus" and "outbreak," we 2435 nonduplicate articles identified in PubMed, EMBASE, and Web of Knowledge published between January 1993 and June 2011. Inclusion criteria included outbreaks with a minimum of 2 ill persons with a common exposure and at least 1 reversetranscription polymerase chain reaction-confirmed case of NoV disease. Univariate analyses were performed, and multivariable models were fitted to estimate the independent effect of each factor. Results. We analyzed 843 NoV outbreaks reported in 233 published articles from 45 countries. Based upon 71 724 illnesses, 501 hospitalizations, and 45 deaths, overall hospitalization and mortality rates were 0.54% and 0.06%, respectively. In multivariate analysis, genogroup 2 genotype 4 (GII.4) NoV strains were associated with higher hospitalization (incidence rate ratio IRR, 9.4; 95% confidence interval CI, 6.1-14.4; P < .001) and mortality rates (IRR, 3.1; 95% CI, 1.3-7.6; P = .01). Deaths were much more likely to occur in outbreaks occurring in healthcare facilities (IRR, 60; 95% CI, 6-109; P = .01). Conclusions. Our review suggests that hospitalizations and deaths were more likely in outbreaks associated with GII.4 viruses, independent of other factors, and underscores the importance of developing vaccines against GII.4 viruses to prevent severe disease outcomes.
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