With the growing appreciation for the influence of the intestinal microbiota on human health, there is increasing motivation to design and refine interventions to promote favorable shifts in the microbiota and their interactions with the host. Technological advances have improved our understanding and ability to measure this indigenous population and the impact of such interventions. However, the rapid growth and evolution of the field, as well as the diversity of methods used, parameters measured and populations studied, make it difficult to interpret the significance of the findings and translate their outcomes to the wider population. This can prevent comparisons across studies and hinder the drawing of appropriate conclusions. This review outlines considerations to facilitate the design, implementation and interpretation of human gut microbiota intervention studies relating to foods based upon our current understanding of the intestinal microbiota, its functionality and interactions with the human host. This includes parameters associated with study design, eligibility criteria, statistical considerations, characterization of products and the measurement of compliance. Methodologies and markers to assess compositional and functional changes in the microbiota, following interventions are discussed in addition to approaches to assess changes in microbiota-host interactions and host responses. Last, EU legislative aspects in relation to foods and health claims are presented. While it is appreciated that the field of gastrointestinal microbiology is rapidly evolving, such guidance will assist in the design and interpretation of human gut microbiota interventional studies relating to foods. ; Peer reviewed
With the growing appreciation for the influence of the intestinal microbiota on human health, there is increasing motivation to design and refine interventions to promote favorable shifts in the microbiota and their interactions with the host. Technological advances have improved our understanding and ability to measure this indigenous population and the impact of such interventions. However, the rapid growth and evolution of the field, as well as the diversity of methods used, parameters measured and populations studied, make it difficult to interpret the significance of the findings and translate their outcomes to the wider population. This can prevent comparisons across studies and hinder the drawing of appropriate conclusions. This review outlines considerations to facilitate the design, implementation and interpretation of human gut microbiota intervention studies relating to foods based upon our current understanding of the intestinal microbiota, its functionality and interactions with the human host. This includes parameters associated with study design, eligibility criteria, statistical considerations, characterization of products and the measurement of compliance. Methodologies and markers to assess compositional and functional changes in the microbiota, following interventions are discussed in addition to approaches to assess changes in microbiota–host interactions and host responses. Last, EU legislative aspects in relation to foods and health claims are presented. While it is appreciated that the field of gastrointestinal microbiology is rapidly evolving, such guidance will assist in the design and interpretation of human gut microbiota interventional studies relating to foods.
Background:Klebsiellapneumoniae colonizesskin,nasopharynx,gastro-intestinal tract,and oropharynx of hospitalized individuals.KlebsiellacausesPneumonia,Meningitis(neonates),Urinarytractinfections,Intra-abdominal infections,Skin and Soft tissue infections in both community and health-caresettings.It became a challenge to the ID(Infectious Disease) physicians to treat Klebsiella infections due to increasing resistance to various antibiotics which led to significant morbidity and mortality. This study was done to know the change in the trend of antibiotic susceptibility pattern of K. pneumoniae for a period of 2 years and to identify Extended Spectrum β-lactamase and AmpCβ-lactamase producing organisms. Materials and Methods:This is a prospective study done in the Department of Microbiology,Siddhartha Medical College,Vijayawada for a period of 2 years(August 2019- July 2021).Blood,pus, andurine specimens received from both Out-patients and In-patients of Government General Hospital,Vijayawada during the study period weresubjected to culture according to CLSI guidelines.Antibioticsusceptibility testing was done by modified Kirby-Bauer disc diffusion method on Muller-Hinton agar.ESBL and AmpC β-lactamase producing organisms were identified using Cefotaxime(30µg), Ceftazidime + Clavulanic acid (30µg/10µg) and Cefoxitin(30µg) discs respectively. Results: Out of the 3021 and 3558 samples received during period 1(August 2019 – July 2020) and period 2(August 2020 to July 2021),254 and 320 K.pneumoniae were isolated respectively.167(65%) isolates toPiperacillin-Tazobactam(PIT), 13(5.1%)isolates to Amikacin(AK)and 6(2.36%)isolates to Meropenem(MR) were resistant during period 1.240(75%)isolates to PIT,40(12.5%)isolatesto AK and 28(8.75%)isolates to MR were resistant during period 2.More than 50% resistance was observed toCefoxitin,Co-trimoxazole, and Ciprofloxacin during both periods 1 and 2.57 ESBL,8 AmpC β-lactamase producing organisms were identified during period 1 and 108 ESBL,25AmpCβ-lactamaseproducing ...
GD and AWW receive core funding support from the Scottish Government's Rural and Environmental Science and Analytical Services (RESAS) Division. JW was funded by the Wellcome Trust [Grant No. 098051]. JVL is funded by MRC New Investigator Grant (MR/P002536/1) and ERC Starting Grant (715662). JK is funded by NIHR: II-OL-1116-10027, NIH: R01-CA204403-01A1, Horizon H2020: ITN GROWTH. Imperial Biomedical Research Centre, SAGES research grant. Infrastructure support for this research was provided by the NIHR Imperial biomedical Research Centre (BRC). Microbiota analyses were carried out using the Maxwell computer cluster at the University of Aberdeen. We thank the Illumina MiSeq team at the Wellcome Sanger Institute for their assistance. This work was partially described in the Ph.D. thesis of KD (Retrieved 2020, Pediatric inflammatory bowel disease Monitoring, nutrition and surgery, https://pure.uva.nl/ws/files/23176012/Thesis_complete_.pdf). ; Peer reviewed ; Publisher PDF
El control de residuos de sustancias antimicrobianas en productos de origen animal como la carne bovina, es de gran importancia porque los residuos pueden generar en las personas que los consumen problemas de salud como alergias, cambios en la flora intestinal y resistencia antimicrobiana en bacterias. En Colombia, la vigilancia del cumplimiento de los Límites Máximos de Residuos LMRs de antimicrobianos veterinarios en carne bovina es limitada, debido a que la capacidad analítica es insuficiente para monitorear un gran número de muestras y un amplio rango de antibióticos. Uno de los métodos de elección para la detección de residuos, es el bioensayo microbiológico descrito en la Guía de Laboratorio de Microbiología MLG 34.02, desarrollado por la agencia de salud pública FSIS del Departamento de Agricultura de Estados Unidos USDA, para la detección, identificación y semi-cuantificación de residuos antimicrobianos. Éste documento presenta la evaluación preliminar que se realizó del bioensayo por primera vez en Colombia, para la determinación de residuos de cuatro antimicrobianos en músculo diafragmático de bovinos machos y hembras de varias edades y procedencias, sacrificados en la planta de beneficio ubicada en Bogotá D.C. "Frigorífico Guadalupe EFEGE", como contribución al sistema de gestión de inocuidad en el marco del Acuerdo sobre la aplicación de Medidas Sanitarias y Fitosanitarias. El protocolo de estandarización del bioensayo usó tejidos provenientes de animales no tratados con medicamentos veterinarios, las matrices se fortificaron con diferentes concentraciones de penicilina G potásica, oxitetraciclina, eritromicina y estreptomicina, como representantes de cuatro familias de antimicrobianos de uso veterinario, y se establecieron preliminarmente criterios de funcionamiento del método bajo algunos lineamientos de la guía de la Decisión Europea 2002/657/CE. El bioensayo mostró excelente especificidad (ningún falso-positivo); los límites de detección se determinaron para los cuatro antibióticos en relación con sus respectivos límites máximos de residuos: Betalactámicos (penicilina G =LMR), tetraciclinas (oxitetraciclina=LMR), macrólidos (eritromicina =LMR) y aminoglucósidos (estreptomicina 4 LMR); sin embargo, la sensibilidad del bioensayo para este último no fue satisfactoria. La exactitud relativa calculada para los límites de detección de los cuatro antimicrobianos fue satisfactoria; la estabilidad de los analitos en la matriz fortificada al límite de detección, resultó adecuada durante el período de tiempo evaluado. Una vez estandarizado el bioensayo, se evaluaron ciento cuatro muestras de músculo bovino tomadas en la planta de beneficio, no detectando residuos que violaran los límites permitidos por el Codex Alimentarius. De manera paralela, las muestras fueron procesadas y analizadas mediante los métodos microbiológicos del hisopo y la prueba comercial Premi® Test, determinando resultados concordantes en todas las pruebas. Adicionalmente, se analizaron tejidos de un bovino dosificado con un antibiótico compuesto de penicilina y estreptomicina. Los tejidos probados presentaron residuos violatorios de penicilina, pero resultaron negativos para el caso de estreptomicina, corroborando la baja sensibilidad del método para la detección del aminoglucósido. La evaluación preliminar del bioensayo, mejoró la capacidad analítica del laboratorio oficial (Laboratorio Nacional de Insumos Pecuarios-LANIP) en su calidad de autoridad sanitaria responsable de la inocuidad de los alimentos en Colombia, contribuyendo a la implementación del "Programa de Control de Residuos de Medicamentos Veterinarios" para el país, orientado a garantizar la inocuidad alimentaria para mejorar las condiciones de competitividad y cumplir los requisitos del comercio internacional de alimentos de origen animal. ; Abstract. The control of antimicrobial residues in cattle meat is important, since these residues can generate in people who consume health problems like allergies, changes in the intestinal flora and antimicrobial resistance. In Colombia, the vigilance of the Maximum Residue Limits MRLs of veterinary antimicrobials in cattle meat is limited, because the analytical capacity is insufficient to monitor a large number of samples and a wide range of antibiotics. One of the methods of choice for the detection of residues microbiological bioassay is described in the Microbiology Laboratory Guide MLG 34.02 that is a microbiological method developed by the health public agency of the United States Department of Agriculture (USDA) for the detection, identification and semi-quantification of antimicrobial residues. This paper shows the preliminary evaluation of bioassay was performed for the first time in Colombia, for the detection of four antimicrobials in diaphragm muscle of bovine males and females of various ages and backgrounds, slaughtered in the processing plant located in Bogota DC "Frigorífico Guadalupe EFEGE", as contribution to the safety management system under the Agreement on the Application of Sanitary and Phytosanitary Measures. The standardization protocol of bioassay used tissues from animals not treated with veterinary drugs, the matrix were fortified with varying concentrations of penicillin G potassium, oxytetracycline, erythromycin and streptomycin, as representatives of the four most important families of antibiotics used in veterinary, and it was preliminarily established the method performance criteria under some guidelines of the European Decision 2002/657/. The test showed excellent specificity (no false positive); detection limits were determined for the four antibiotics in relation to their respective Maximum Residue Limit MRLs: Beta-lactams (penicillin G =MRL), tetracyclines (oxytetracycline =MRL) and macrolides (erythromycin =LMR), the detection limits meet with the LMRs in bovine muscle according to national legislation. However, the sensitivity of the bioassay aminoglycosides (streptomycin 4 MRL); however, the sensitivity of bioassay for the last one was unsatisfactory. The relative accuracy for limits of detection of antimicrobial four was satisfactory. Stability of the analytes in the matrix was adequate during the period evaluated. With the standardized bioassay method, it were evaluated one hundred four bovine muscle samples taken at the processing plant, not detecting residues breaking out the permit limits allowed by the Codex Alimentarius. In parallel, samples were processed and analyzed by swab microbiological methods and the commercial test Premi ® Test, determining concordant results among all tests. Additionally, incurred tissues with a product containing penicillin and streptomycin were evaluated. Muscle samples analyzed by bioassay showed penicillin violated residues, but were negative for streptomycin, which confirms the low sensitivity of the method for detection of aminoclycoside. The preliminary assessment of the microbiological bioassay analytical method made, improved analytical capability official laboratory (Laboratorio Nacional de Insumos Pecuarios-LANIP) in his capacity as health authority responsible for food safety in Colombia, will support the implementation of the "Programme for Control of Veterinary Drugs" in our country, contributing to ensure food safety to enhance the competitiveness and meet the requirements of international trade in food of animal origin. ; Maestría
Bacillus cereus sensu lato comprises Gram-positive spore-forming bacteria producing toxins associated with foodborne diseases. Three pore-forming enterotoxins, nonhemolytic enterotoxin (Nhe), hemolysin BL (Hbl), and cytotoxin K (CytK), are considered the primary factors in B. cereus sensu lato diarrhea. The aim of this study was to determine the potential risk of enterotoxicity among soil B. cereus sensu lato isolates representing diverse phylogroups and originated from different geographic locations with various climates (Burkina Faso, Kenya, Argentina, Kazakhstan, and Poland). While nheA- and hblA-positive isolates were present among all B. cereus sensu lato populations and distributed across all phylogenetic groups, cytK-2-positive strains predominated in geographic regions with an arid hot climate (Africa) and clustered together on a phylogenetic tree mainly within mesophilic groups III and IV. The highest in vitro cytotoxicity to Caco-2 and HeLa cells was demonstrated by the strains clustered within phylogroups II and IV. Overall, our results suggest that B. cereus sensu lato pathogenicity is a comprehensive process conditioned by many intracellular factors and diverse environmental conditions. ; Izabela Święcicka - izabelas@uwb.edu.pl ; Justyna Drewnowska - Department of Microbiology, Faculty of Biology, University of Bialystok, Bialystok, Poland ; Natalia Stefańska - Department of Microbiology, Faculty of Biology, University of Bialystok, Bialystok, Poland ; Magdalena Czerniecka - Department of Cytobiochemistry, Faculty of Biology, University of Bialystok, Bialystok, Poland; Laboratory of Tissue Culture, Faculty of Biology, University of Bialystok, Bialystok, Poland ; Grzegorz Zambrowski - Laboratory of Applied Microbiology, University of Bialystok, Bialystok, Poland ; Izabela Święcicka - Department of Microbiology, Faculty of Biology, University of Bialystok, Bialystok, Poland; Laboratory of Applied Microbiology, University of Bialystok, Bialystok, Poland ; Mock M, Fouet A. 2001. Anthrax. 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Salmonella enterica serovar Typhimurium DT 104 is the major pathogen for salmonellosis outbreaks in Europe. We tested if the probiotic bacterium Enterococcus faecium NCIMB 10415 can prevent or alleviate salmonellosis. Therefore, piglets of the German Landrace breed that were treated with E. faecium (n=16) as a feed additive and untreated controls (n=16) were challenged with S. Typhimurium 10 days after weaning. The presence of salmonellae in feces and selected organs, as well as the immune response, were investigated. Piglets treated with E. faecium gained less weight than control piglets (P=0.05). The feeding of E. faecium had no effect on the fecal shedding of salmonellae and resulted in a higher abundance of the pathogen in tonsils of all challenged animals. The specific (anti-Salmonella IgG) and nonspecific (haptoglobin) humoral immune responses as well as the cellular immune response (T helper cells, cytotoxic T cells, regulatory T cells, +¦+¦ T cells, and B cells) in the lymph nodes, Peyer's patches of different segments of the intestine (jejunal and ileocecal), the ileal papilla, and in the blood were affected in the course of time after infection (P < 0.05) but not by the E. faecium treatment. These results led to the conclusion that E. faecium may not have beneficial effects on the performance of weaned piglets in the case of S. Typhimurium infection. Therefore, we suggest a critical discussion and reconsideration of E. faecium NCIMB 10415 administration as a probiotic for pigs.
