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1.
Sci Rep ; 13(1): 13991, 2023 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-37634024

RESUMEN

Climatic changes and elevated ambient temperature are significant environmental stressors with a negative impact on birds' physiological, immunological, and behavioral status, increasing their susceptibility to stressors and immunosuppression and consequently increasing intestinal permeability (leaky gut). Prebiotics have been utilized to stop or diminish the harmful effects of stress in chickens. We aimed to evaluate the role of mannan-oligosaccharides, and beta-D-glucan prebiotics supplements in drinking water against experimentally induced heat stress (HS) on broiler chickens and study their impact on birds' performance, gut microbiome, and immune response. A total of 120 1-day-old Ross broiler chicks were allocated into four groups (30 birds/group), and each group was subdivided into triplicates (10 birds each). The experimental groups were classified as follows; the 1st (G1) control birds, the 2nd (G2) birds exposed experimentally to HS, the 3rd (G3) birds administered prebiotics in drinking water without exposure to HS, and the 4th (G4) birds exposed to HS and administered prebiotics in drinking water. After each vaccination, blood samples and serum samples were collected to evaluate the birds' immune status. Fecal samples were also collected for the molecular evaluation of the gut microbiome based on the genetic analyses and sequencing of 16S rRNA gene. The results showed that HS has reduced the birds' performance and badly affected the birds' immune response and gut microbiome. However, the addition of prebiotics to drinking water, with or without stress, enhanced the growth rate, maintained a normal gut microbiome, and improved immune parameters. Moreover, the usage of prebiotics improved the chicken gut microbiome and alleviated the negative effect of heat stress. Administering prebiotics significantly (p < 0.05) increased the relative abundance of beneficial bacteria and eradicated pathogenic ones in the birds' gut microbiome. Prebiotics showed a positive effect on the gut microbiome and the immune status of chickens under HS in addition to their efficacy as a growth promoter.


Asunto(s)
Agua Potable , Microbioma Gastrointestinal , Trastornos de Estrés por Calor , Animales , Pollos , Prebióticos , ARN Ribosómico 16S/genética , Fiebre , Inmunidad
2.
Genes (Basel) ; 13(6)2022 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-35741753

RESUMEN

Mycobacterium tuberculosis complex (MTBC) Lineage 3 (L3) strains are abundant in world regions with the highest tuberculosis burden. To investigate the population structure and the global diversity of this major lineage, we analyzed a dataset comprising 2682 L3 strains from 38 countries over 5 continents, by employing 24-loci mycobacterial interspersed repetitive unit-variable number of tandem repeats genotyping (MIRU-VNTR) and drug susceptibility testing. We further combined whole-genome sequencing (WGS) and phylogeographic analysis for 373 strains representing the global L3 genetic diversity. Ancestral state reconstruction confirmed that the origin of L3 strains is located in Southern Asia and further revealed multiple independent introduction events into North-East and East Africa. This study provides a systematic understanding of the global diversity of L3 strains and reports phylogenetic variations that could inform clinical trials which evaluate the effectivity of new drugs/regimens or vaccine candidates.


Asunto(s)
Mycobacterium tuberculosis , Genotipo , Pruebas de Sensibilidad Microbiana , Repeticiones de Minisatélite , Mycobacterium tuberculosis/genética , Filogenia
3.
Toxicon ; 195: 7-16, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33610638

RESUMEN

Aflatoxins are carcinogenic compounds produced by certain Aspergillus spp and naturally contaminate poultry rations. Exposure to low levels of Aflatoxin B1 (AFB1) in poultry feeds is the second most threatening issue facing the poultry industry in Egypt; it can cause a reduction in growth, egg production, and compromised immune functions, resulting in significant economic loss. Hence, a safe, effective and eco-friendly detoxification method is strongly required. Biological decontamination is a promising approach to reduce aflatoxin levels within threshold limits. This study explores the biodegradation capacity of bacteria isolated from the moldy feed, soil and poultry feces in various poultry farms against AFB1 (100 ppb), G1 (100 ppb), B2 (30 ppb), G2 (30 ppb). Sixty-five bacterial isolates were initially screened using coumarin media with a concentration of (0.01%-0.5%) coumarin. Only one soil isolate (SZ1) grew at the highest concentration (0.5%). Coumarin and Aflatoxin degradation rates of ten promising isolates were measured using spectrophotometry and HPLC. Six isolates reduced AFG1 by more than 90% in the liquid medium, five reduced AFB2 while only four did the same with AFB1& AFG2. Impressively, isolate SZ1 (identified as Pseudomonas fluorescens) exhibited the best degradation capacity to both coumarin and aflatoxin with 100% degradation of AFG1 and 99% degradation of AFB1, AFB2 and AFG2. Biochemical and molecular identification of the ten isolates revealed that they belong to four genera; Bacillus (6), Pseudomonas (2), Enterococcus (1) and Stenotrophomonas (1). Factors affecting Pseudomonas fluorescens SZ1 degradation activity was further investigated. Optimum temperature, time and pH for maximum aflatoxin degradation were at 37 °C, 72 h and 7, respectively. Treatment with proteinase K reduced the degradation activity of G1 (31% ± 1.438), B1 (42% ± 1.438), G2 (19% ± 1.097), and B2 (25% ± 1.732), suggesting that the effective component in aflatoxin degradation may be protein in nature. Our study suggests the biocontrol potential of several different species isolated from poultry farms; B. haynesii, B. licheniformis, B. tequilensis, B. subtilis, B. amyloliquefaciens, Pseudomonas fluorescens, Enterococcus casseliflavus, and Stenotrophomonas maltophilia. The results proposed Pseudomonas fluorescens SZ1 as an excellent candidate for bioremediation and decontamination of aflatoxin in feed matrices. To the best of our knowledge, this is the first report identifying B. haynesii, Enterococcus casseliflavus, B. tequilensis and B. amyloliquefaciens with aflatoxin degradation activity.


Asunto(s)
Aflatoxinas/metabolismo , Biodegradación Ambiental , Aflatoxina B1/análisis , Aflatoxinas/análisis , Animales , Egipto , Enterococcus , Granjas , Aves de Corral
4.
Int J Mycobacteriol ; 8(3): 211-217, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31512595

RESUMEN

Background: This study explored the genetic diversity of Mycobacterium tuberculosis isolates in Egypt by spoligotyping in combination with pncA gene sequencing, spoNC. Methods: First, isolates were selected from 400 isolates positive for M. tuberculosis that referred to Central Labs Ministry of Health and then were subjected to the study analyses. Results: Twenty one isolates were found to be multidrug resistant (MDR) and 29 isolates were sensitive for isonizide (INH) and rifampicine (RIF) after testing by phenotypic drug susceptibility testing (DST) and Mycobacteria Growth Indicator Tube (MGIT). Spoligotyping yielded 45 patterns belonging to seven families that previously reported in neighboring countries such as Iraq, Syria, Iran, and Turkey. While four isolates were orphans. Conclusion: Application of spoNC on obtained spoligotype patterns enhances to reduce the clustering rate. Bejing family the predominant (34%) were subdivided by pncA sequence into three sensitive DST pncA wild type, three MDR-DST isolates showing cys14Arg mutation in pncA, two sensitive DST isolates with pncA Gly97Asp mutation, and three sensitive DST pncAVal128Gly mutation. The next most common CASI_DELHI family (16%) were subdivided by pncA sequencing into CASI_DELHI (st 381, MDR) including two pncA silent mutation ser65ser (tcc > tct) and CASI_DELHI (st26, sensitive) which included six pncA (wild-type) results, and Latin-American-Mediterranean 6 family (6%) all had PncA Gly97Asp mutation. We concluded that spoNC provides good snap shot for MDR surveillance and its country origin and performs early identification of outbreaks in Egypt.


Asunto(s)
Amidohidrolasas/genética , Mutación , Mycobacterium tuberculosis/genética , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Adolescente , Adulto , Anciano , Antituberculosos/farmacología , Técnicas de Tipificación Bacteriana , Egipto , Monitoreo Epidemiológico , Femenino , Variación Genética , Genotipo , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Mycobacterium tuberculosis/efectos de los fármacos , Estudios Prospectivos , Pirazinamida/farmacología , Rifampin/farmacología , Análisis de Secuencia de ADN , Esputo/microbiología , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Adulto Joven
5.
Artículo en Inglés | MEDLINE | ID: mdl-30559939

RESUMEN

Background: Since the time of Hippocrates, dress of the care-giver has been known to influence patient's perception about the physician. Objectives: To explore patient's preference about physician's dress in Saudi primary healthcare, and how it influences their perception, regarding professionalism, competence, and confidence in the physician. Methods: A cross sectional study conducted in primary care clinics in Riyadh, enrolling 443 patients, who filled a self-administered Arabic questionnaire, enquiring about physician clothes such as white coat, scrubs and 'thob (white-robe) shomagh (head cover)' for males, 'veil-skirt' for females, and shoes. Patients' preferences about physicians' dresses were explored and influence of favorable dress on professionalism and trustworthiness were explored, using Chi-sq, Mann Whitney, with p ≤ .05 as significant. Principle component analysis was used to search themes in attire commonly used. Results: Over 80% of patients visiting Saudi primary care, liked seeing their physician in white coat. Traditional dress 'thob and shomagh' was approved by 47% whereas 'veil and skirt' got acceptance of 62%. Dress of physician was significantly (p < .005) more important to patients, who were male (Chi-sq 14.95), working (Chi-sq 9.39), educated (Chi-sq 9.84), urbanites (Chi-sq 18.34) and married (Chi-sq 7.89). Patients who valued physician attire (70%) perceived it positively influencing doctor-patient relationship: Mann Whitney U score = 6879, p-value <0.001. Four dress-themes emerged: 'Professional modest', 'Expensive modern', 'Traditional formal' and 'Casual shoes'. Conclusion: Patients preferred white coats for their doctors. Half of participants accepted traditional dresses. Majority valued physician's attire as a positive influence.

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