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1.
Environ Sci Pollut Res Int ; 31(28): 41059-41068, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38842777

RESUMO

Lead (Pb) can be deposited in aquatic environments that are especially subject to pollution due to wastewater and sewage disposal. This study aimed to evaluate the tolerance of Echinodorus grandiflorus (Cham. & Schltr.) Micheli to Pb and changes in growth, gas exchange, and leaf anatomy. Experiments were conducted with E. grandiflorus plants exposed to the following Pb concentrations in nutrient solution: [0; 0.75; 1.5; 3.0 and 9.0 µM Pb (NO 3)2] in a greenhouse for 60 days. At the end of the experiment, the lead concentration, growth, leaf gas exchange, and changes in leaf anatomy were evaluated. There was no mortality of E. grandiflorus plants, and they accumulated higher concentrations of Pb proportional to the concentration of the pollutant in the solution. Pb did not cause significant changes in growth, stomatal conductance, transpiration, and Ci/Ca rate but reduced the photosynthesis in E. grandiflorus. The leaf anatomy showed significant changes in the presence of Pb, reducing the epidermis and chlorophyll parenchyma. E. grandiflorus demonstrated tolerance to Pb, surviving and growing under contamination; however, it negatively modified its leaf anatomy and photosynthesis in the presence of the metal.


Assuntos
Chumbo , Folhas de Planta , Folhas de Planta/anatomia & histologia , Folhas de Planta/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Alismataceae/anatomia & histologia
2.
Appl Microbiol Biotechnol ; 107(23): 7231-7250, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37741937

RESUMO

Staphylococcus aureus is one of the most relevant mastitis pathogens in dairy cattle, and the acquisition of antimicrobial resistance genes presents a significant health issue in both veterinary and human fields. Among the different strategies to tackle S. aureus infection in livestock, bacteriophages have been thoroughly investigated in the last decades; however, few specimens of the so-called jumbo phages capable of infecting S. aureus have been described. Herein, we report the biological, genomic, and structural proteomic features of the jumbo phage vB_SauM-UFV_DC4 (DC4). DC4 exhibited a remarkable killing activity against S. aureus isolated from the veterinary environment and stability at alkaline conditions (pH 4 to 12). The complete genome of DC4 is 263,185 bp (GC content: 25%), encodes 263 predicted CDSs (80% without an assigned function), 1 tRNA (Phe-tRNA), multisubunit RNA polymerase, and an RNA-dependent DNA polymerase. Moreover, comparative analysis revealed that DC4 can be considered a new viral species belonging to a new genus DC4 and showed a similar set of lytic proteins and depolymerase activity with closely related jumbo phages. The characterization of a new S. aureus jumbo phage increases our understanding of the diversity of this group and provides insights into the biotechnological potential of these viruses. KEY POINTS: • vB_SauM-UFV_DC4 is a new viral species belonging to a new genus within the class Caudoviricetes. • vB_SauM-UFV_DC4 carries a set of RNA polymerase subunits and an RNA-directed DNA polymerase. • vB_SauM-UFV_DC4 and closely related jumbo phages showed a similar set of lytic proteins.


Assuntos
Bacteriófagos , Fagos de Staphylococcus , Animais , Bovinos , Feminino , Humanos , Fagos de Staphylococcus/genética , Staphylococcus aureus/genética , Proteômica , Genoma Viral , Genômica , Bacteriófagos/genética , RNA Polimerases Dirigidas por DNA/genética , RNA de Transferência
3.
J Plant Res ; 136(4): 535-548, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37103629

RESUMO

The objective of this study was to evaluate the relationship between intercellular spaces and leaf gas exchange and the effect of total intercellular space on the growth of maize and sorghum under water restriction. The experiments were conducted in a greenhouse in a 2 × 3 factorial arrangement (two plant types and three water conditions: field capacity (FC = 100%), 75%FC, and 50%FC) with 10 replicates. The lack of water was a limiting factor for maize because it showed reductions in leaf area, leaf thickness, biomass, and gas exchange parameters, while sorghum remained unchanged, maintaining its water-use efficiency. This maintenance was correlated with the growth of intercellular spaces in sorghum leaves because the increased internal volume led to better CO2 control and prevented excessive water loss under drought stress. In addition, sorghum had more stomata than maize. These characteristics contributed to the drought tolerance of sorghum, while maize could not make the same adjustments. Therefore, changes in intercellular spaces promoted adjustments to avoid water loss and may have improved CO2 diffusion, characteristics that are important for drought-tolerant plants.


Assuntos
Sorghum , Água , Fotossíntese , Espaço Extracelular , Dióxido de Carbono , Folhas de Planta , Secas
4.
Foods ; 12(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36900609

RESUMO

Gut microbiota imbalance is associated with the occurrence of metabolic diseases such as obesity. Thus, its modulation is a promising strategy to restore gut microbiota and improve intestinal health in the obese. This paper examines the role of probiotics, antimicrobials, and diet in modulating gut microbiota and improving intestinal health. Accordingly, obesity was induced in C57BL/6J mice, after which they were redistributed and fed with an obesogenic diet (intervention A) or standard AIN-93 diet (intervention B). Concomitantly, all the groups underwent a treatment phase with Lactobacillus gasseri LG-G12, ceftriaxone, or ceftriaxone followed by L. gasseri LG-G12. At the end of the experimental period, the following analysis was conducted: metataxonomic analysis, functional profiling of gut microbiota, intestinal permeability, and caecal concentration of short-chain fatty acids. High-fat diet impaired bacterial diversity/richness, which was counteracted in association with L. gasseri LG-G12 and the AIN-93 diet. Additionally, SCFA-producing bacteria were negatively correlated with high intestinal permeability parameters, which was further confirmed via functional profile prediction of the gut microbiota. A novel perspective on anti-obesity probiotics is presented by these findings based on the improvement of intestinal health irrespective of undergoing antimicrobial therapy or not.

5.
Nutrients ; 14(24)2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36558393

RESUMO

The Western diet can negatively affect the gut microbiota and is associated with metabolic disorders. Kombucha, a tea fermented by a symbiotic culture of bacteria and yeast (SCOBY), is known for its bioactive properties and has become popular in the last years. In this study, we evaluated the effects of regular kombucha consumption on the gut microbiota and on outcomes related to the intestinal health of Wistar rats fed a high-fat high-fructose diet. After eight weeks receiving a standard diet (AIN-93M) (n = 10) or a high-fat and high-fructose diet (HFHF) (n = 30) to induce metabolic disorders, the animals were subdivided into four groups: AIN-93M (n = 10); HFHF (n = 10); GTK (HFHF + green tea kombucha (n = 10); and BTK (HFHF + black tea kombucha; n = 10) for 10 weeks. Although body composition did not differ among the groups, the HFHF diet was associated with metabolic alterations, and stimulated the growth of gram-negative bacteria such as Proteobacteria and Bacteroides. Kombucha ingestion could somewhat modulate the gut microbiota, attenuating the effects of a Western diet by increasing propionate production and favoring the growth of beneficial bacteria, such as Adlercreutzia in the GTK group. Our results suggest that regular kombucha consumption may be beneficial to intestinal health, which can be mostly attributed to its high content and diversity of phenolic compounds.


Assuntos
Camellia sinensis , Microbioma Gastrointestinal , Ratos , Animais , Chá/microbiologia , Ratos Wistar , Frutose/farmacologia , Polifenóis/farmacologia , Dieta Hiperlipídica/efeitos adversos
6.
Foods ; 11(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35159437

RESUMO

We hypothesized that the consumption of chia (Salvia hispanica L.) flour (CF) and chia oil (CO) improves metabolic disorders in the liver of Wistar rats (Rattus norvegicus domestica) fed a high-fat and high-fructose (HFHF) diet. The animals were fed a HFHF diet (n = 30) or AIN93-M standard diet (n = 10) for eight weeks. After this period, the animals fed HFHF were divided into three groups (n = 10): HFHF diet, HFHF plus 14.7% of CF, and HFHF plus 4% of CO. Histological and biochemical analyses, gene expression, protein levels related to inflammation, and oxidative stress were evaluated in the liver. The HFHF diet caused lipogenesis, liver steatosis, oxidative stress, and inflammation in the animals. The CF and CO intake increased the liver total antioxidant capacity and superoxide dismutase, decreased nitric oxide levels and liver steatosis. Furthermore, the CF and CO led to the upregulation of Cpt1a and Adipor2, respectively, whereas CF downregulated Srebf1. CO intake decreased blood glucose, triglycerides, and the animals' body weight. Chia did not show effects on mitigating liver pro-inflammatory status, which it may indicate occurs later. The addition of chia into an unbalanced diet is a good and relevant strategy to reduce liver metabolic disorders caused by the high consumption of fructose and saturated fat.

7.
Environ Sci Pollut Res Int ; 29(13): 19878-19889, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35080729

RESUMO

Typha domingensis Pers. is a plant that grows in marshy environments, where cadmium (Cd) accumulates. The root is the first organ that comes into contact with the metal. The aim of this study was to evaluate the effect of Cd on the roots of T. domingensis. The experiment was conducted in a greenhouse using different Cd concentrations: (1) 0 µM (control), (2) 10 µM, and (3) 50 µM, with 10 replicates for 90 days. The plants were placed in plastic containers containing 5 L of nutrient solution modified with the different Cd concentrations. At the end of the experiment, the roots were measured, sampled, fixed, and subjected to usual plant microtechniques. The slides were observed and photographed under light microscopy and analyzed in ImageJ software. To measure Cd absorption, atomic-absorption spectrometry was used. The data were subjected to analysis of variance and comparison of means by the Scott-Knott test at P < 0.05. When exposed to 50 µM of Cd, the roots accumulated 99.35% of the Cd. At this concentration, there was a reduction in the exodermis but there was an increase in the diameter of the cortical cells and in the proportion of aerenchyma in the cortex. There was an increase in the root cap, which guaranteed the protection of the primary meristems. Therefore, T. domingensis adjusts its root anatomy improving the Cd tolerance and shows potential for phytoremediation purposes.


Assuntos
Typhaceae , Biodegradação Ambiental , Cádmio/análise , Raízes de Plantas/química , Plantas , Áreas Alagadas
8.
Protoplasma ; 259(4): 1081-1097, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34755230

RESUMO

This work aimed to evaluate the effects of lower water levels on leaf intercellular spaces and to assess their relations with the gas exchange, anatomy, and growth of Sorghum bicolor. Experiments were conducted in a greenhouse, in which plants were subjected to three water conditions (ten replicates, n = 30): well-irrigated, decreased irrigation, and limited irrigation. Lower water levels had no significant effect on the growth of S. bicolor but increased the biomass of the roots. Moreover, the number of leaves, leaf area, and leaf size as well as the chlorophyll content were not affected by lower water levels, and no significant changes were detected for whole plant photosynthesis, transpiration, or stomatal conductance. The water content of the plants and the water potential remained unchanged. However, compared with other treatments, the decreased irrigation decreased water loss and increased the water retention. Lower water levels increased the intercellular CO2 percentage, mesophyll area, and proportion of stomatal cavities and promoted minor changes in leaf tissue and stomatal traits. The increased stomatal cavities provided higher CO2 uptake and prevented excessive water loss. Thus, modifications to the intercellular spaces promoted conditions to avoid excessive water loss while concurrently improving CO2 uptake, which are important traits for drought-tolerant plants.


Assuntos
Sorghum , Dióxido de Carbono/farmacologia , Fotossíntese , Folhas de Planta , Transpiração Vegetal , Água
9.
Ciênc. rural (Online) ; 52(6): e20210277, 2022. ilus, graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1350580

RESUMO

In vitro tests are performed to evaluate the efficacy of antimycotoxins additives (AMAs); nevertheless, such assays show a low correlation with in vivo trials, which are also required to determine AMAs' efficacy. In search of an alternative method, the current study investigated the use of an ex vivo technique. Six AMAs (AMA1 to AMA6) had their ability to reduce intestinal absorption of aflatoxin B1 (AFB1) evaluated. Jejunal explants were obtained from broilers and subjected to two treatments per AMA in Ussing chambers: T1 (control) - 2.8 mg/L AFB1, and T2 - 2.8 mg/L AFB1 + 0.5% AMA. AMAs were also tested in vitro to assess adsorption of AFB1 in artificial intestinal fluid. In the ex vivo studies, AMA1 to AMA6 decreased intestinal absorption of AFB1 by 67.11%, 73.82%, 80.70%, 85.86%, 86.28% and 82.32%, respectively. As for the in vitro results, AMA1 to AMA6 presented an adsorption of 99.72%, 99.37%, 99.67%, 99.53%, 99.04% and 99.15%, respectively. The evaluated ex vivo model proved useful in the assessment of AMAs. No correlation was reported between ex vivo and in vitro findings. Further studies are needed to elucidate the correlation between ex vivo and in vivo results seeking to reduce animal testing.


Testes in vitro são realizados para avaliar a eficácia de aditivos antimicotoxinas (AAMs); entretanto, tais experimentos apresentam uma baixa correlação com ensaios in vivo, que também são exigidos para determinar a eficácia de AAMs. Em busca de um método alternativo, o presente estudo investigou o uso de uma técnica ex vivo. A capacidade de seis AAMs (AAM1 a AAM6) de reduzir a absorção intestinal de aflatoxina B1 (AFB1) foi avaliada. Explantes jejunais foram coletados de frangos de corte e submetidos a dois tratamentos por AAM em câmaras de Ussing: T1 (controle) - 2,8 mg/L AFB1, e T2 - 2.8 mg/L AFB1 + 0,5% AAM. Os AAMs também foram testados in vitro para verificar a adsorção de AFB1 em fluido intestinal artificial. Nos ensaios ex vivo, AAM1 ao AAM6 diminuíram a absorção intestinal de AFB1 em 67,11%, 73,82%, 80,70%, 85,86%, 86,28% e 82,32%, respectivamente. Quanto aos achados in vitro, AAM1 ao AAM6 apresentaram adsorção de 99,72%, 99,37%, 99,67%, 99,53%, 99,04% e 99,15%, respectivamente. O modelo ex vivo avaliado mostrou-se eficiente na avaliação de AAMs. Não houve correlação entre os resultados ex vivo e in vitro. Estudos adicionais são necessários para definir a correlação entre achados ex vivo e in vivo na tentativa de reduzir os testes em animais.


Assuntos
Animais , Antitoxinas/análise , Galinhas , Aflatoxina B1/toxicidade , Jejuno , Técnicas In Vitro
10.
Physiol Plant ; 173(4): 2323-2333, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34625976

RESUMO

The present study aimed to evaluate root cortical aerenchyma formation in response to Cd-driven hydrogen peroxide (H2 O2 ) production and the role of nitric oxide (NO) in the alleviation of Cd oxidative stress in maize roots and its effects on aerenchyma development. Maize plants were subjected to continuous flooding for 30 days, and the following treatments were applied weekly: Cd(NO3 )2 at 0, 10, and 50 µM and Na2 [Fe(CN)5 NO]·2H2 O (an NO donor) at 0.5, 0.1, and 0.2 µM. The root biometrics; oxidative stress indicators H2 O2 and malondialdehyde (MDA); and activities of catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX) were analyzed. The root dry and fresh masses decreased at higher concentrations of NO and Cd. H2 O2 also decreased at higher NO concentrations; however, MDA increased only at higher Cd levels. SOD activity decreased at higher concentrations of NO, but CAT activity increased. Aerenchyma development decreased in response to NO. Consequently, NO acts as an antagonist to Cd, decreasing the concentration of H2 O2 by reducing SOD activity and increasing CAT activity. Although H2 O2 is directly linked to aerenchyma formation, increased H2 O2 concentrations are necessary for root cortical aerenchyma development.


Assuntos
Cádmio , Óxido Nítrico , Antioxidantes , Ascorbato Peroxidases/metabolismo , Cádmio/toxicidade , Catalase/metabolismo , Peróxido de Hidrogênio , Estresse Oxidativo , Espécies Reativas de Oxigênio , Superóxido Dismutase/metabolismo
11.
Toxicon ; 200: 102-109, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34217749

RESUMO

The impact of deoxynivalenol (DON) upon intestinal tissue of broilers was assessed by using jejunal explants in Ussing chambers and analyzing histopathological and immunohistochemical parameters; this system was also applied to evaluate the efficacy of an antimycotoxins additive (AMA). The explants were subjected to the following treatments within each experiment for 120 min: Experiment 1) T1 (control) - buffer solution, and T2 - 10 mg/L DON; and Experiment 2) T1 (control) - buffer solution, T2 - 10 mg/L DON, T3 - AMA (0.5%), and T4 - 10 mg/L DON + 0.5% AMA. In Experiment 1, DON triggered a reduction in the size of enterocytes as well as of their nuclei, an increase in cytoplasmic vacuolization and apical denudation of villi. Apoptotic cells count was also greater in DON-exposed explants. In Experiment 2, the AMA mitigated DON harmful effects; cytoplasmic vacuolization of enterocytes was reduced and the size of their nuclei was preserved. The additive also promoted a partial decrease in microvillus integrity, in size of enterocytes and in apoptotic cells count. The tested ex vivo model demonstrated the impact of DON upon the intestine as well as the efficacy of the AMA against its damaging effects.


Assuntos
Galinhas , Tricotecenos , Ração Animal/análise , Animais , Intestinos , Jejuno , Tricotecenos/toxicidade
12.
Protoplasma ; 258(4): 765-777, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33404920

RESUMO

Radial oxygen loss is a physical phenomenon that occurs naturally in aquatic plants. Typha domingensis was chosen as a model plant because it possesses basic morphological characteristics, such as a stem (rhizome) that produces leaves and adventitious roots, which are present in many aquatic plants. This study aimed to evaluate the following: the relevance of the anatomy of T. domingensis on gas diffusion among organs; the influence of plant parts on radial oxygen loss; the role of catalase in radial oxygen loss; and the proposition of a novel explanation for the downward diffusion of oxygen through the organs of this aquatic macrophyte and into the environment. Typha domingensis plants were cultivated in a greenhouse under different conditions: plants with intact leaves, plants with leaves cut in half, and plants without leaves. Furthermore, we evaluated the percentage of aerenchyma in different vegetative organs, the minimum pressure required for radial oxygen loss, the daily variations of dissolved oxygen, and the roots' catalase activity. The results demonstrated that certain cellular features contributed to decreased oxygen diffusion among the organs, specifically, those found in the leaf-rhizome and root-rhizome interfaces as well as the suberin and lignin layers in these regions. Additionally, our experiments with a catalase activator and inhibitor validated that a significant amount of the oxygen released in radial oxygen loss could not, in fact, be exclusively supplied by the atmosphere. Thus, a complementary model is proposed in which catalase activity is an important component of radial oxygen loss.


Assuntos
Typhaceae , Catalase , Oxigênio , Folhas de Planta , Raízes de Plantas
13.
FEMS Microbiol Lett ; 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33270833

RESUMO

The teaching-learning process becomes more attractive when practical classes are used as part of methodological tools. Aiming (i) to stimulate the interest of high school students in the microbiological world and (ii) to provide didactic experience for microbiology graduate students, practical classes were undertaken. These classes were carried out during the years 2016 and 2017, using the infrastructure held at Universidade Federal de Viçosa. Briefly, laboratory classes were prepared and taught by microbiology graduate students and an evaluation questionnaire was answered by the participants after the classes. Approximately 95% of the high school students, from both years, evaluated the experience outside of the school routine as very good and good. A total of 90.09% (2016) and 100% (2017) of graduate students evaluated this experience as very good and good. The relationship between high school and graduate students also increased the curiosity of the former regarding the university environment. Accordingly, the information retention regarding the 'microbiology world' was verified after one year and the students were able to remember important terms related to the microbiology class. In addition, this work allowed graduate students and high school students to build a closer relationship and created an excellent teaching-learning strategy for both.

14.
BMC Surg ; 20(1): 260, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33126885

RESUMO

BACKGROUND: Minimally invasive liver resections (MILRs) have been increasingly performed in recent years. However, the majority of MILRs are actually minor or limited resections of peripheral lesions. Due to the technical complexity major hepatectomies remain challenging for minimally invasive surgery. The aim of this study was to compare the short and long-term outcomes of patients undergoing minimally invasive right hepatectomies (MIRHs) with contemporary patients undergoing open right hepatectomies (ORHs) METHODS: Consecutive patients submitted to anatomic right hepatectomies between January 2013 and December 2018 in two tertiary referral centers were studied. Study groups were compared on an intention-to-treat basis after propensity score matching (PSM). Overall survival (OS) analyses were performed for the entire cohort and specific etiologies subgroups RESULTS: During study period 178 right hepatectomies were performed. After matching, 37 patients were included in MIRH group and 60 in ORH group. The groups were homogenous for all baseline characteristics. MIRHs had significant lower blood loss (400 ml vs. 500 ml, P = 0.01), lower rate of minor complications (13.5% vs. 35%, P = 0.03) and larger resection margins (10 mm vs. 5 mm, P = 0.03) when compared to ORHs. Additionally, a non-significant decrease in hospital stay (ORH 9 days vs. MIRH 7 days, P = 0.09) was observed. No differences regarding the use of Pringle's maneuver, operative time, overall morbidity or perioperative mortality were observed. OS was similar between the groups (P = 0.13). Similarly, no difference in OS was found in subgroups of patients with primary liver tumors (P = 0.09) and liver metastasis (P = 0.80). CONCLUSIONS: MIRHs are feasible and safe in experienced hands. Minimally invasive approach was associated with less blood loss, a significant reduction in minor perioperative complications, and did not negatively affect long-term outcomes.


Assuntos
Hepatectomia , Laparoscopia , Neoplasias Hepáticas , Feminino , Humanos , Tempo de Internação , Neoplasias Hepáticas/cirurgia , Masculino , Duração da Cirurgia , Complicações Pós-Operatórias/epidemiologia , Pontuação de Propensão , Estudos Retrospectivos , Resultado do Tratamento
15.
Appl Microbiol Biotechnol ; 104(20): 8837-8857, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32902682

RESUMO

Colorectal cancer is a public health problem, with dysbiosis being one of the risk factors due to its role in intestinal inflammation. Probiotics and synbiotics have been used in order to restore the microbiota balance and to prevent colorectal carcinogenesis. We aimed to investigate the effects of the probiotic VSL#3® alone or in combination with a yacon-based prebiotic concentrate on the microbiota modulation and its influence on colorectal carcinogenesis in an animal model. C57BL/6J mice were divided into three groups: control (control diet), probiotic (control diet + VSL#3®), and synbiotic (yacon diet + VSL#3®). The diets were provided for 13 weeks and, from the third one, all animals were subjected to induction of colorectal cancer precursor lesions. Stool samples were collected to evaluate organic acids, feces pH, ß-glucuronidase activity, and microbiota composition. The colon was used to count pre-neoplastic lesions and to determine the cytokines. The microbiota composition was influenced by the use of probiotic and synbiotic. Modifications were also observed in the abundance of bacterial genera with respect to the control group, which confirms the interference of carcinogenesis in the microbiota. Pre-neoplastic lesions were reduced by the use of the synbiotic, but not with the probiotic. The protection provided by the synbiotic can be attributed to the modulation of the intestinal inflammatory response, to the inhibition of a pro-carcinogenic enzyme, and to the production of organic acids. The modulation of the composition and activity of the microbiota contributed to beneficial changes in the intestinal microenvironment, which led to a reduction in carcinogenesis. KEY POINTS: • Synbiotic reduces the incidence of colorectal cancer precursor lesions. • Synbiotic modulates the composition and activity of intestinal microbiota. • Synbiotic increases the abundance of butyrate-producing bacteria.


Assuntos
Neoplasias Colorretais , Microbioma Gastrointestinal , Probióticos , Simbióticos , Animais , Carcinogênese , Neoplasias Colorretais/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Microambiente Tumoral
16.
Sci Rep ; 10(1): 5520, 2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-32218514

RESUMO

Brazil has the second-largest dairy cattle herd in the world, and bovine mastitis still can cause significant losses for dairy farmers. Despite this fact, little information is available about milk microbial composition of Brazilian dairy cows, as well as the potential use of bacteriophages in the control of S. aureus. Here, we investigated milk bacterial composition of 28 Holstein Fresian cows (109 teats), selected in the dry-off period, using 16S rRNA analysis. Furthermore, a representative S. aureus strain (UFV2030RH1) was obtained at drying-off for isolation of a bacteriophage (vB_SauM-UFV_DC4, UFV_DC4) and bacterial genomic comparison purposes. Our outcomes revealed that Staphylococcus was the third most prevalent genus and positively correlated with subclinical mastitis events. As a major finding, genomic analyses showed the presence of adhesive matrix molecules that recognize microbial surface components (MSCRAMM) in UFV2030RH1 and might indicate great biofilm formation capability. A minimum inhibitory concentration (MIC) assay showed that resistance to ampicillin was the highest among the antibiotic tested in S. aureus 3059 and UFV2030RH1, displaying values four and sixteen times greater than MIC resistance breakpoint, respectively. Together, our results suggest that Staphylococcus is highly prevalent in dairy cows at drying-off and the use of the phage UFV_DC4 as a biocontrol agent must be investigated in future studies.


Assuntos
Mastite Bovina/microbiologia , Leite/microbiologia , RNA Ribossômico 16S/genética , Fagos de Staphylococcus/fisiologia , Staphylococcus aureus/classificação , Resistência a Ampicilina , Animais , Antibacterianos/farmacologia , Bovinos , DNA Bacteriano/genética , DNA Ribossômico/genética , Feminino , Genômica , Mastite Bovina/prevenção & controle , Filogenia , Análise de Sequência de DNA , Fagos de Staphylococcus/isolamento & purificação , Staphylococcus aureus/genética , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/virologia
18.
Rev Soc Bras Med Trop ; 52: e20180121, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30994793

RESUMO

INTRODUCTION: This study aimed to analyze the survival of septic patients and to assess prognostic factors. METHODS: Patients with sepsis, severe sepsis, and septic shock were followed up and clinical and laboratory data were collected. The sepsis-related organ failure assessment (SOFA) score was calculated. RESULTS: The overall 30-day survival rates of patients with sepsis, severe sepsis, and septic shock were 86.3%, 72.5%, and 20%, respectively. Mortality was related to old age, septic shock, coagulopathy, lactate level, and high SOFA score among other factors. CONCLUSIONS: Identification of prognostic variables may reduce sepsis-related mortality.


Assuntos
Sepse/mortalidade , Brasil/epidemiologia , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
19.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;52: e20180121, 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1041601

RESUMO

Abstract INTRODUCTION: This study aimed to analyze the survival of septic patients and to assess prognostic factors. METHODS: Patients with sepsis, severe sepsis, and septic shock were followed up and clinical and laboratory data were collected. The sepsis-related organ failure assessment (SOFA) score was calculated. RESULTS: The overall 30-day survival rates of patients with sepsis, severe sepsis, and septic shock were 86.3%, 72.5%, and 20%, respectively. Mortality was related to old age, septic shock, coagulopathy, lactate level, and high SOFA score among other factors. CONCLUSIONS: Identification of prognostic variables may reduce sepsis-related mortality.


Assuntos
Humanos , Masculino , Feminino , Sepse/mortalidade , Prognóstico , Brasil/epidemiologia , Métodos Epidemiológicos , Pessoa de Meia-Idade
20.
Viruses ; 11(1)2018 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-30583530

RESUMO

Streptococcus thermophilus is considered one of the most important species for the dairy industry. Due to their diffusion in dairy environments, bacteriophages can represent a threat to this widely used bacterial species. Despite the presence of a CRISPR-Cas system in the S. thermophilus genome, some lysogenic strains harbor cryptic prophages that can increase the phage-host resistance defense. This characteristic was identified in the dairy strain S. thermophilus M17PTZA496, which contains two integrated prophages 51.8 and 28.3 Kb long, respectively. In the present study, defense mechanisms, such as a lipoprotein-encoding gene and Siphovirus Gp157, the last associated to the presence of a noncoding viral DNA element, were identified in the prophage M17PTZA496 genome. The ability to overexpress genes involved in these defense mechanisms under specific stressful conditions, such as phage attack, has been demonstrated. Despite the addition of increasing amounts of Mitomycin C, M17PTZA496 was found to be non-inducible. However, the transcriptional activity of the phage terminase large subunit was detected in the presence of the antagonist phage vB_SthS-VA460 and of Mitomycin C. The discovery of an additional immune mechanism, associated with bacteriophage-insensitive strains, is of utmost importance, for technological applications and industrial processes. To our knowledge, this is the first study reporting the capability of a prophage integrated into the S. thermophilus genome expressing different phage defense mechanisms. Bacteriophages are widespread entities that constantly threaten starter cultures in the dairy industry. In cheese and yogurt manufacturing, the lysis of Streptococcus thermophilus cultures by viral attacks can lead to huge economic losses. Nowadays S. thermophilus is considered a well-stablished model organism for the study of natural adaptive immunity (CRISPR-Cas) against phage and plasmids, however, the identification of novel bacteriophage-resistance mechanisms, in this species, is strongly desirable. Here, we demonstrated that the presence of a non-inducible prophage confers phage-immunity to an S. thermophilus strain, by the presence of ltp and a viral noncoding region. S. thermophilus M17PTZA496 arises as an unconventional model to study phage resistance and potentially represents an alternative starter strain for dairy productions.


Assuntos
Genoma Viral , Prófagos/imunologia , Streptococcus thermophilus/imunologia , Streptococcus thermophilus/virologia , Integração Viral , Genoma Bacteriano/genética , Lipoproteínas/genética , Mitomicina/farmacologia , Inibidores da Síntese de Ácido Nucleico/farmacologia , RNA não Traduzido/genética , Streptococcus thermophilus/efeitos dos fármacos
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