Screening Of Faecal Samples Research Articles

Fecal metabolomic profiles: A comparative study of patients with colorectal cancer vs adenomatous polyps.

BACKGROUNDColorectal cancer (CRC), the third most common cause of death in both males and females worldwide, shows a positive response to therapy and usually a better prognosis when detected at an early stage. However, the survival rate declines when the diagnosis is late and the tumor spreads to other organs. Currently, the measures widely used in the clinic are fecal occult blood test and evaluation of serum tumor markers, but the lack of sensitivity and specificity of these markers restricts their use for CRC diagnosis. Due to its high sensitivity and precision, colonoscopy is currently the gold-standard screening technique for CRC, but it is a costly and invasive procedure. Therefore, the implementation of custom-made methodologies including those with minimal invasiveness, protection, and reproducibility is highly desirable. With regard to other screening methods, the screening of fecal samples has several benefits, and metabolomics is a successful method to classify the metabolite shift in living systems as a reaction to pathophysiological influences, genetic modifications, and environmental factors.AIMTo characterize the variation groups and potentially recognize some diagnostic markers, we compared with healthy controls (HCs) the fecal nuclear magnetic resonance (NMR) metabolomic profiles of patients with CRC or adenomatous polyposis (AP).METHODSProton nuclear magnetic resonance spectroscopy was used in combination with multivariate and univariate statistical approaches, to define the fecal metabolic profiles of 32 CRC patients, 16 AP patients, and 38 HCs well matched in age, sex, and body mass index.RESULTSNMR metabolomic analyses revealed that fecal sample profiles differed among CRC patients, AP patients, and HCs, and some discriminatory metabolites including acetate, butyrate, propionate, 3-hydroxyphenylacetic acid, valine, tyrosine and leucine were identified.CONCLUSIONIn conclusion, we are confident that our data can be a forerunner for future studies on CRC management, especially the diagnosis and evaluation of the effectiveness of treatments.

First Insights Into Within Host Translocation of the Bacillus cereus Toxin Cereulide Using a Porcine Model.

Bacillus cereus is a gram-positive pathogen mainly known to evoke two types of foodborne poisonings. The diarrheal syndrome is caused by enterotoxins produced during growth in the intestine. In contrast, the emetic type is caused by the dodecadepsipeptide cereulide pre-formed in food. Usually, both diseases are self-limiting but occasionally more severe forms, including fatal ones, are reported. Since the mechanisms of cereulide toxin uptake and translocation within the body as well as the mechanism of its toxic action are still unknown, we used a porcine model to investigate the uptake, routes of excretion and distribution of cereulide within the host. Pigs were orally challenged with cereulide using single doses of 10–150 μg cereulide kg-1 body weight to study acute effects or using daily doses of 10 μg cereulide kg-1 body weight administered for 7 days to investigate effects of longtime, chronic exposure. Our study showed that part of cereulide ingested with food is rapidly excreted with feces while part of the cereulide toxin is absorbed, passes through membranes and is distributed within the body. Results from the chronic trial indicate bioaccumulation of cereulide in certain tissues and organs, such as kidney, liver, muscles and fat tissues. Beside its detection in various tissues and organs, our study also demonstrated that cereulide is able to cross the blood–brain–barrier, which may partially explain the cerebral effects reported from human intoxication cases. The neurobehavioral symptoms, such as seizures and lethargy, observed in our porcine model resemble those reported from human food borne intoxications. The rapid onset of these symptoms indicates direct effects of cereulide on the central nervous system (CNS), which warrant further research. The porcine model presented here might be useful to study the specific neurobiological effect in detail. Furthermore, our study revealed that typical diagnostic specimens used in human medicine, such as blood samples and urine, are not suitable for diagnostics of food borne cereulide intoxications. Instead, screening of fecal samples by SIDA-LC-MS may represent a simple and non-invasive method for detection of cereulide intoxications in clinical settings as well as in foodborne outbreak situations.

Salivirus infection in children with diarrhea, Thailand.

A new member of the Picornaviridae family named salivirus, and also known as klassevirus, was identified recently from the feces of children with gastroenteritis. At present, it remains unclear whether salivirus is associated with gastroenteritis in humans and epidemiological data are very limited. To investigate the prevalence of salivirus in Thailand, we performed molecular screening of fecal samples from children hospitalized with acute gastroenteritis in Chiang Mai, Thailand during 2015-2016 through theapplication of RT-nested PCR. Salivirus was detected in 1 out of 229 (0.44%) fecal samples tested and it belonged to genotype A1, based on nucleotide sequences of the 5'UTR, VP1, and 3D regions. This is the first report of salivirus infection in young children with acute diarrhea in Thailand.

High proportion of ESBL-carriers among neonates in a tertiary hospital in Ecuador

Study design A prospective, descriptive study. The setting was a NICU in a third level hospital in Ecuador. From January to April 2011, stool specimens were collected, every two weeks, from all neonates hospitalized. The screening of fecal samples for ESBL producing Enterobacteriaceae, was performed on MacConkey agar containing cefotaxime and ceftazidime 1 mg/L. Antimicrobial susceptibility testing was performed following Clinical and Laboratory Standards Institute guidelines, and phenotypic confirmation was performed using the disk diffusion method on Muller-Hinton agar plates with disks containing ceftazidime and cefotaxime with and without clavulanic acid. Aim

Emergence of Escherichia coli sequence type 410 (ST410) with KPC-2 β-lactamase

Fifteen carbapenem-non-susceptible Escherichia coli isolates obtained during the period May 2010 to April 2011 in a hospital and a long-term care facility (LTCF) in Larissa (Central Greece) were investigated. Minimum inhibitory concentrations (MICs) to various antimicrobial agents were determined by Etest. Carriage of bla genes, including blaKPC-2 and blaCTX-M, was documented by polymerase chain reaction (PCR) and sequencing. Production of β-lactamases was confirmed by isoelectric focusing. Transfer of resistance was carried out by conjugation. Plasmid incompatibility groups were determined by PCR-based replicon typing and replicon sequence typing. Isolates were genotyped by multilocus sequence typing. Ten E. coli isolates with KPC-2 were derived from seven patients in the University Hospital of Larissa. Six patients had previously been treated for prolonged time periods in a LTCF located in the same city. The remaining isolate was from a patient previously treated in an Athens hospital. Screening of faecal samples from 20 randomly selected LTCF patients yielded eight enterobacteria with KPC-2, of which five were E. coli, showing the wide spread of KPC-2-producers in this institution and confirming that it was the focus of the outbreak. Fourteen of the isolates were classified as sequence type 410 (ST410); the remaining isolate belonged to a novel ST (ST2281). All 15 isolates carried a KPC-2-encoding plasmid of the Inc group FIIK. Additional plasmids encoding enzymes of the CTX-M-1 family were identified in 11 isolates. The blaKPC-2-carrying plasmid IncFIIK, widespread amongst Klebsiella pneumoniae in Greece, has probably been acquired by E. coli ST410 known to be associated with CTX-M production. Diffusion of blaKPC-2 in common pathogens such as E. coli is of concern.

Occurrence of water-borne enteric viruses in two settlements based in Eastern Chad: analysis of hepatitis E virus, hepatitis A virus and human adenovirus in water sources

Hepatitis E virus (HEV) is a common cause of water-borne acute hepatitis in areas with poor sanitation. In 2004 an outbreak of HEV infection affected around 2,000 people in Eastern Chad (Dar Sila). This paper describes the decrease in the incidence of acute jaundice syndrome (AJS) from 2004 until 2009 when a mean incidence of 0.48 cases/1,000 people/year was recorded in the region. Outbreaks of AJS were identified in some of the camps in 2007 and 2008. Moreover, water samples from drinking water sources were screened for human adenoviruses considered as viral indicators and for hepatitis A virus and HEV. Screening of faecal samples from donkeys for HEV gave negative results. Some of the samples were also analysed for faecal coliforms showing values before disinfection treatment between 3 and >50 colony forming units per 100 mL. All water samples tested were negative for HEV and HAV; however, the presence of low levels of human adenoviruses in 4 out of 16 samples analysed indicates possible human faecal contamination of groundwater. Consequently, breakdowns in the treatment of drinking water and/or increased excretion of hepatitis viruses, which could be related to the arrival of a new population, could spread future outbreaks through drinking water.

Nucleic acid-based analyses of non-group A rotaviruses.

Simple genome profile studies on polyacrylamide gels allow all non-group A rotaviruses isolated so far to be recognized by the absence of the tight triplet (7-9) of RNA segments seen in all group A viruses. However, reliance solely on genome profile studies for rotavirus grouping can be misleading and, for virus group definition, additional corroborating nucleic acid and serological studies are essential. Terminal fingerprint analysis was the first generation of nucleic acid-based assays that allowed discrimination between the various rotavirus groups. By means of this technique the clear definition of five rotavirus groups (A-E), correlating exactly with those found by a serological assay, has been possible, with preliminary evidence for at least two additional groups. The technical sophistication of fingerprinting techniques prevents their widespread use in epidemiological studies; the development of a second generation of nucleic acid-based assays is therefore under way. These employ molecularly cloned cDNA probes to the genomes of non-group A viruses which can be widely distributed for use in 'dot-blot' screening of faecal samples and, if expressed as protein in Escherichia coli, should provide a ready source of viral antigen for use in surveying viral prevalence through the screening of serum antibody levels.