Indiscriminate use of antibiotics has led to an increas- ing incidence of antibiotic resistance among strains of enterobacteriaceae, worldwide (French, 2010; Hiramatsu et al., 1997). In the last two decades, ESbLs have emerged as a major contributor of drug resistance. In this study a total of 69 isolates of entericbacteria were isolated from 50 sam- ples of hospital wastewater in the vicinity of Aligarh city, India. On the basis of morphological, cultural and biochem- ical characteristics, these isolates were grouped into four different genera, Escherichia (18 isolates), Citrobacter (07), Shigella (11), and Klebsiella (04). Other twenty nine isolates could not be differentiated on the basis of biochem- ical tests and grouped as unidentified (miscellaneous) en- teric bacteria. These characteristics of entericbacteria were similar to those reported in literature (Ananthnarayan and Paniker, 1986). Further molecular characterization of these isolates is needed to explore their genetic linkages. The findings revealed that the wastewater discharged from hos- pital is heavily loaded with multiple drug resistant entericbacteria and can be a plausible source for contamination to the other natural water bodies.
The aim of this study was to evaluate the occurrence of yeasts, pseudomonads and entericbacteria in the oral cavity of patients undergoing radiotherapy (RT) for treatment of head and neck cancer. Fifty patients receiving RT were examined before, during and 30 days after RT. Saliva, mucosa, and biofilm samples were collected and microorganisms were detected by culture and polymerase chain reaction (PCR). The most prevalent yeasts in patients submitted to RT were Candida albicans, C. tropicalis, C. krusei, C. glabrata and C. parapsilosis. Citrobacter, Enterobacter, Enterococcus, Klebsiella, Proteus, and Pseudomonas were the most frequently cultivated bacteria. Before RT, targeted bacteria were cultivated from 22.2% of edentulous patients and 16.6% of dentate patients; 30 days after RT, these microorganisms were recovered from 77.8% edentulous and 46.8% dentate patients. By PCR, these microorganisms were detected from all edentulous patients, 78.1% of dentate patients. The presence of Gram-negative enteric roads and fungi was particularly frequent in patients presenting mucositis level III or IV. Modifications in the oral environment due to RT treatment seem to facilitate the colonization of oral cavity by members of family Enterobacteriaceae, genera Enterococcus and Candida.
Because the weaker metabolic activity of bacteria under starving conditions could alter the infectivity and the induced signal [34,35], we tested the detection of E. coli TD2158 in non ster- ilized and non-filtered sea water samples. Furthermore, the photosynthetic plankton naturally present in sea water emits autofluorescence and could provoke false positive results. Water samples were loaded with 2x10 6 bacteria.ml -1 then they were incubated at 20°C for 20 h to mimic contamination by entericbacteria. Thus, E. coli TD2158 cells should be in the same met- abolic state than Enterobacteria present during an accidental contamination of water. Under such conditions, Enterobacteria such as TD2158 should not grow. To test that, we spiked a sea water sample with fluorescent bacteria (LCB6139) and measured the number of cells by flow cytometry before and after incubation in sea water for 20 h at 20°C. We observed that for an initial bacterial load of 4.98 x 10 6 bacteria.ml -1 , the cell count measured after incubation was 2.93 x 10 6 bacteria.ml -1 . Therefore, the cells did not divide under such conditions, but around 50% are rather dying, probably due to predators (protozoa) naturally occurring in non treated sea water samples. Consequently, for each experiment, we measured the number of cfu after incubation, and these numbers were set as references for the dilution assays. Fig 4A shows that infected bacteria emitted strong green fluorescence intensity after resuspension into LB medium and infection at 30°C for 1 h. The region representing the target population was desig- nated TD. By contrast, no bacteria was present in the TD region either when cells were not infected with HK620::PrrnB-gfp or when non spiked sample was infected with phages (Fig 4A). These controls confirmed that the detection was specific to E. coli TD2158 cells infected with HK620::PrrnB-gfp. Moreover, the multiparametric data obtained by using flow cytometry allowed to discriminate green fluorescent bacteria from autofluorescent bacteria present in sea water such as Synechococcus. This microorganism presents a specific fluorescence profile due to its pigment content, essentially chlorophyll and phycoerythrin, which emits red and orange fluorescence, respectively. Due to overlapping spectra, orange fluorescence was detected using the green fluorescence channel allowing Synechococcus population detection on dot-plots of red fluorescence intensity versus green fluorescence intensity (Fig 4A). Under starving condi- tions, reactivation of the metabolism was slower, and therefore spiked samples had to be resus- pended in rich medium (see Materials and Methods). Flow cytometry analysis decreased the false positive risk because naturally autofluorescent bacteria were discriminated from target
Since the detection of Salmonella sp., V. cholerae and V. alginolyticus was not quantitative, the results were expressed as isolation percentage using the presence or absence of these bacteria in each sample. Coliforms at 45 °C, Escherichia coli, V. parahaemolyticus, and V. vulnificus were expressed as isolation percentage and as MPN enumeration. The results for the V. parahaemolyticus and V. vulnificus isolation were then statistically analyzed to observe any correlation between the presence of vibrios and water temperature. Differences in the incidence of the Vibrio spp. in oysters in different seasons of the year were evaluated by ANOVA (p < 0.05), and mean differences were evaluated using Tukey`s test. Statistical analyses of the data were performed with the Statistica® 6.0 software.
Table 1 shows the concentrations of the extracts of guava leaves which were tested against strains of Staphylococcus aureus, Salmonella and Escherichia coli isolated from seabob shrimp. The inhibition haloes seen surrounding discs soaked in the extracts varied from 7.00 mm to 11.25 mm with all the bacteria being sensitive to at least one of the extracts. The methanol extract inhibited bacterial growth more than hexane and ethyl acetate. The solvents, without plant extract, were used as negative controls and did not inhibit bacterial growth.
Figure 1. Anthrax LT causes intestinal damage in C57BL/6J and BALB/c mice. (A) C57BL/6J and BALB/c mice were injected intravenously with anthrax LT or the PBS vehicle alone. Intestines obtained from moribund (LT-treated) or control (PBS-treated) animals were photographed and assessed for gross pathological changes. Arrowheads indicate areas of hemorrhage. Areas of edema are marked by the letter ‘‘E’’. (B and C) C57BL/6J and BALB/c mice were injected intravenously with anthrax LT (n = 34 and n = 14, respectively) or the PBS vehicle alone (n = 15 and n = 10, respectively). LT-treated mice were sacrificed when they became moribund; PBS-treated mice were sacrificed simultaneously as controls. Shown are representative H&E sections from the small intestines of LT- and PBS-treated C57BL/6J mice (B, n = 34), and BALB/c mice (C, n = 14). All mice within each strain displayed similar histological findings. Arrows indicate mucosal erosions/ulcerations, and arrowheads identify areas of hemorrhage. Aperio ScanScope-acquired images are shown at 56. (D) Shown are adjacent sections from a typical ulcer in a moribund LT-treated C57BL/6J mouse stained with H&E (left panels) or Brown & Brenn (right panels). High magnification reveals the submucosal penetration of bacteria. Aperio ScanScope-acquired images are shown at 26 or 206.
Human norovirus (HNoV), is a common source of contamination (Wang et al. 2012), but there is still not totally established an in vitro cell culture system for the detection of infectious wild type norovirus due to the cellular tropism of human NoVs (HuNoVs) and also for the absence of stimulatory carbohydrate molecules because HuNoVs are well known to bind histo-blood group antigens (HBGAs) which are expressed by the host. ¬-Recently Jones et al., (2015) demonstrated a biologically substantial role for entericbacteria during NoV infection leading to the development of an in vitro infection model for human noroviruses.
Y. enterocolitica is a species of gram-negative coccobacillus-shaped bacteria, belonging to the family Enterobacteriaceae. It infects many animal species and it is resistant to the external environment (Wang et al., 2010). It has been isolated from feces of healthy dogs and cats. Domestic animals excrete Y. enterocolitica in their feces for many weeks and may be a source of infection for humans. In a survey in China from 2004 to 2008, 326 strains of Y. enterocolitica were isolated from people with diarrhea and it was demonstrated that there is a close relationship between strains of domestic dogs and of humans’ strains (Wang et al., 2010). Nevertheless, the direct zoonotic transmission of Y. enterocolitica has not been proven until now (Robins-Browne, 1997). However, people who have come into contact with infected animals suffered from enterocolitis, indicating possible zoonotic transmission (Wang et al., 2010).
CARVALHO, R.F. Essential oils as rumen fermentation modifier for enteric methane mitigation in ruminants. [Óleos essenciais como modificadores da fermentação ruminal para mitigação de metano entérico em ruminantes]. 2018. 95 f. Tese (Doutorado em Ciências) – Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, 2018. The search for natural products which can increase animal productivity and reduce environmental impact has been intensified. Some plant extracts, such as essential oils, are used as feed additives able of improving ruminal fermentation by modulating the production of short chain fatty acids and inhibiting methanogenesis. The objective of this study was to evaluate the production of enteric and feces methane, as well as feeding behaviour, ruminal fermentation and kinetics of dairy and beef cattle fed with different essential oils. Eight non-pregnant, non-lactating and ruminally canullated cows were used: four were the dairy breed Holstein, and four were the beef breed Nellore. The diet was composed of 70% of roughage (corn silage) and 30% of concentrate (corn grain and soybean meal), the treatments differed only in relation to the essential oil added: CNT, a diet without any additive; EEO, a diet with 500 mg/kg of DM of eucalyptus (Eucalyptus citriodora) essential oil; PEO, a diet with 500 mg/kg of DM of Brazilian peppertree (Schinus terebinthifolius Raddi) essential oil, and LEO, a diet with 500 mg/kg of DM of lemongrass (Cymbopogon citratus Stapf) essential oil. The experimental design was the 4x4 contemporary latin square in a 2x4 factorial arrangement (referring to two specialized cattle breeds and four additives). The evaluation of the CH4 production of the manure was performed through experimental batch anaerobic digesters, in a completely randomized design. The beef cattle had lower DMI (P = 0.0413), they spent more time consuming, ruminating or chewing 1 kg of DM or NDF (min/kg), also had higher values for acetate, butyrate or total SCFA production than dairy cattle. The manure from dairy cattle had higher biogas production (L/gVS add) or CO2 (liters, percentage and L/gVS add) than the manure of beef cattle. The treatments with essential oils had on average 23% more rumination events per day than the control treatment (P = 0.0201). Diet containing essential oils decreased N2O production of feces from dairy cattle. The essential oils in the dosage used did not affect rumen fermentation and kinetics, as well as the emission of enteric methane and feces.
The enteric health of growing poultry is imperative to success of the production. The basic role of poultry production is turning feed stuffs into meat. Any changes in this turning process, due to mechanical, chemical or biological disturbance of digestive system (enteric disorders) is mostly accompanied with high economic losses due to poor performance, increased mortality rates and increased medication costs. The severity of clinical signs and course of the disorders are influenced by several factors such as management, nutrition and the involved agent(s). Several pathogens (viruses, bacteria and parasites) are incriminated as possible cause of enteric disorders either alone (mono-causal), in synergy with other micro-organisms (multi-causal), or with non-infectious causes such as feed and /or management related factors. In addition, excessive levels of mycotoxins and biogenic amines in feed lead to enteric disorders. Also factors such as high stocking density, poor litter conditions, poor hygiene and high ammonia level and other stressful situation may reduce the resistance of the birds and increases their susceptibility to infections. Under field conditions, however, it is difficult to determine whether the true cause of enteric disorders, is of infectious or non-infectious origin. In recent years and since the ban of use of antimicrobial growth promoters in several countries the incidence of intestinal disorders especially those caused by clostridial infection was drastically increased. The present review described in general the several factors involved in enteric disorders and summarized the available literatures about Clostridium perfringens infection in poultry.
The above study shows that prevalence of enteric fever was found to be high and most commonly observed in adult age group 82%. Enteric fever is a common health problem in developing countries like India, Bangladesh, Sri Lanka, Nepal, and others where water supplies and sanitation are sub- standard. Large number of bacterial organisms and Salmonella species is excreted in urine and faeces specimen. During the diseases, an infection is caused by the entry of the Salmonella species through contaminated food or water or directly from faeces and contaminated fingers. Prevention of enteric fever is mainly by personal and domestic hygiene.
first century, primarily due to the increased emissions of greenhouse gases in the atmosphere. With over 21 times more heat per molecule than carbon dioxide (CO 2 ), meth- ane (CH 4 ) is a particularly potent greenhouse gas and accounts for 16 % of total global greenhouse gas emis- sions. The CH 4 formation is a microbial-driven process, mainly dominated by methanogens, which are members of the Archaea domain and inhabit certain anaerobic environments, such as freshwater sediments abundant in organic matter, swamps and waterlogged soils, sew- age treatment plants as well as the rumen of ruminants (Woese et al., 1978). Nowadays, ruminants can produce globally more than 80 million tons of CH 4, which annu- ally, accounts for 28 % of anthropomorphic emissions, and has drawn attention to the contribution of animal agriculture to global warming (Beauchemin et al., 2008). In ruminants, enteric CH 4 emissions not only contribute to global climate warming, but also account for 2 ~ 12 % of the ingested energy. In particular, for high-produc- ing lactating animals, at least 6 % of gross energy intake is lost by way of CH 4 emissions. Therefore, mitigating CH 4 emissions in ruminants will not only assist in the achievement of international commitments under the Kyoto Protocol but also in the improvement of energy utilization efficiency and the performance of the host animal. Any mitigation option should be undertaken on the basis of a clear understanding of the mechanism of
Higher organisms are continuously exposed to a myriad of foreign components and microorganisms that may threaten their normal function. Mucosal tissues are the main route of microbial invasion, requiring a specialized immune system than maintains its integrity and enables effective protection against these insults. The enteric immune system harbours diffuse lymphocytes that reside in the lamina propria and T cells embedded in the basolateral sides of epithelial cells (ECs). The latter, called intraepithelial lymphocytes (IELs), are key components of the first-line defence against luminal pathogens 2 . The intestinal lamina propria harbours
Rotavirus A and adenovirus are among the most commonly recognized causes of epidemic viral acute gastroenteritis worldwide (Wu et al., 2008). Rotavirus A are considered the major etiological agents of acute diarrhoea in infants and young children (Andreasi et al., 2007). It is a nonenveloped double-stranded RNA virus (Dey et al., 2009b). Rotavirus A infection displays a tendency for seasonality in temperate areas where peaks occur predominantly in winter, but their infection occurs throughout the year in tropical areas (Tiemessen et al., 1989; Inouye et al., 2000). Adenovirus is considered a very significant enteric virus. They are gastroenteritis-associated emerging virus, responsible for a higher number of outbreaks in nurseries, schools and hospitals (Chiba et al., 1983; Van et al., 1992; Mulholland, 2004; Akihara et al., 2005; Muscillo et al., 2008). Human adenovirus belong to the Adenoviridae family and are nonenveloped double-stranded DNA virus. To date more than 51 human adenovirus serotypes have been identified, and classified into six species (A to F) based on biophysical and biochemical criteria (Benkö and Harrach, 2003b; Davison et al., 2003). Adenovirus is associated with gastroenteritis in children, namely the species F (serotypes 40 and 41) and species A (serotypes 12, 18 and 31). Serotypes 40 and 41 are the first responsible for gastroenteritis, being the most frequent serotypes detected in hospitalized children (Uhnoo et al., 1984; Aminu et al., 2007; Shimizu et al., 2007).
at a high frequency in both the diarrheic or nondiarrheic foals. This result is not surprising because this organism is part of the normal enteric microflora of livestock . Despite the recognized pathogenicity of E. coli to humans  and livestock  the major virulence factors of E. coli involved in enteric infections of foals remain unclear . Selected virulence factors of E. coli were assessed in 99 E. coli strains from the foals; three strains from diarrheic foals were positive for Shiga-like toxin genes and another isolate was positive for STb and LT, whereas one strain from a nondiarrheic foal was positive for STb. In addition, eight isolates from diarrheic foals were positive for the eae gene. These findings demonstrate the presence of potentially virulent strains . In the current study, the absence of F4 (k88), F5 (k99), and F41 fimbriae and LT, STa, and STb enterotoxins among the E. coli strains isolated from diarrheic and nondiarrheic foals indi- cates that this organism has little influence on the pathogenic- ity of enteric infections in neonatal foals, despite the fact that F4 and F5 fimbriae are classically involved in enterotoxigenic infections in calves and pigs and have been identified sporad- ically  or at low levels in enteric infections of foals . Other virulence factors related to enteric and/or extraenteric infections in domestic animals, such as the cnf-1 and cnf-2 cytotoxins, papG, sfaC/D, and afaB/C fimbriae and iucD (aer- obactin) and hly genes , were not detected in the 32 E. coli strains assessed in this study, indicating that E. coli may not be
cation Kit (QIAGEN, CA, USA) and then subjected to sequencing. Both strands of DNA in PCR amplicons were sequenced using an ABI Prism 3100 Genetic Ana- lyzer with the Big Dye Terminator Cycle Sequencing Kit v.3.1 (Applied Biosystem, CA, USA). Centri-Sep col- umns (Princeton Separations, CA, USA) were used to purify sequencing reaction products prior to analysis in the genetic analyser. A neighbour-joining phylogenetic tree was constructed from the sequences using MEGA 5 software; 1,000 pseudo replicate data sets were used to achieve a Bootstrap value above 70%. The nucleotide sequences reported in this study are listed in the Gen- Bank database under the accession numbers KM099402 - KM099407. Although non-enteric HAdVs are not rou- tinely screened by RRRL-LVCA, nucleotide sequence analysis can be used to identify these viruses in stool samples from patients with diarrhoea.
onto acetyl-CoA in the lysine fermentation pathway (see above) (Kreimeyer et al. 2007). Construction of a phylogenetic tree of DUF849 also showed that the Pfam DUF849 proteins of lysine fermenters all clustered in a single branch of the tree. Moreover, most members of the Pfam DUF849 family are present in bacteria which do not ferment lysine. We thus hypothesized a generic cleavage reaction conserved within the family and applied on representatives, structural and modeling investigations (based on ASMC), analysis of genomic and metabolic context and ended with high-throughput enzymatic screening. This approach unearthed 14 potential new enzymatic activities, leading to the designation of these proteins as beta-keto acid cleavage enzymes. We propose an in vivo role for four enzymatic activities and suggest key residues for guiding further functional annotation. Our results illustrate also how the functional diversity within a family may be largely underestimated (Bastard et al. 2014).
Table 3 shows the results for enteric viruses detected in naturally contaminated sewage sludge samples using two concentration methods. Method 2 (beef extract elution based method) was better for detecting HAdV, RV-A and NoV when compared with method 1. HAV was only de- tected in one sample by the ultracentrifugation method (Ta- ble 3). The total frequency of detection, independently of used methods, demonstrated that HAdV was the most de- tected (91%) (range: 1.8 x 10 4 to 1.1 x 10 5 GC L -1 ) , fol- lowed by RV-A (range: 8 x 10 3 to 8 x 10 5 GC L -1 ), NoV (range: 1.6 x 10 4 to 4.9 x 10 5 GC L -1 ) (both 50%) and HAV (8%) (8.6 x 10 6 GC L -1 ).
BACTERIA BIOSURFACTANTS PRODUCTION KINETIC EVALUATION. Biosurfactants present advantages in relation to the synthetic surfactants, as the biodegradability and low toxicity, and can be applied in the food industry, in pharmaceutical products, cosmetics and in the petroleum recovery. This paper aimed at selecting bacteria for biosurfactant production, evaluating the surface tension and the emulsifying activity and studying the fermentation process kinetics. The pure culture of Corynebacterium aquaticum showed capacity to promote emulsions formation and presented the smallest surface tension (28.8 mN m -1 ), and, in general, larger
Since its first design in 1986 as an exploratory device, the Atomic Force Microscopy (AFM) has evolved as an instrument for investigating biological materials with variable complexity such as tissues, yeasts, bacteria and their components, providing real-time in situ quantitative morphological information (7, 11). The AFM’s versatility combines high resolution (less than 1 nm) on a sample in native conditions, i.e., the ability to generate detailed images in air and even in liquid, with no conductive coating or staining applications (23). The AFM principle is relatively simple: the object to be scanned is positioned under a fine tip held by a flexible spring