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1.
Mol Cell ; 81(14): 2887-2900.e5, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34171298

RESUMO

WhiB7 represents a distinct subclass of transcription factors in the WhiB-Like (Wbl) family, a unique group of iron-sulfur (4Fe-4S] cluster-containing proteins exclusive to the phylum of Actinobacteria. In Mycobacterium tuberculosis (Mtb), WhiB7 interacts with domain 4 of the primary sigma factor (σA4) in the RNA polymerase holoenzyme and activates genes involved in multiple drug resistance and redox homeostasis. Here, we report crystal structures of the WhiB7:σA4 complex alone and bound to its target promoter DNA at 1.55-Å and 2.6-Å resolution, respectively. These structures show how WhiB7 regulates gene expression by interacting with both σA4 and the AT-rich sequence upstream of the -35 promoter DNA via its C-terminal DNA-binding motif, the AT-hook. By combining comparative structural analysis of the two high-resolution σA4-bound Wbl structures with molecular and biochemical approaches, we identify the structural basis of the functional divergence between the two distinct subclasses of Wbl proteins in Mtb.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas Ferro-Enxofre/metabolismo , Mycobacterium tuberculosis/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica/genética , Proteínas Ferro-Enxofre/genética , Mycobacterium tuberculosis/genética , Regiões Promotoras Genéticas/genética , Fator sigma/genética , Fator sigma/metabolismo , Fatores de Transcrição/genética
2.
J Environ Manage ; 355: 120504, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38447513

RESUMO

Ammonia-oxidation process directly contribute to soil nitrous oxide (N2O) emissions in agricultural soils. However, taxonomy of the key nitrifiers (within ammonia oxidising bacteria (AOB), archaea (AOA) and complete ammonia oxidisers (comammox Nitrospira)) responsible for substantial N2O emissions in agricultural soils is unknown, as is their regulation by soil biotic and abiotic factors. In this study, cumulative N2O emissions, nitrification rates, abundance and community structure of nitrifiers were investigated in 16 agricultural soils from major crop production regions of China using microcosm experiments with amended nitrogen (N) supplemented or not with a nitrification inhibitor (nitrapyrin). Key nitrifier groups involved in N2O emissions were identified by comparative analyses of the different treatments, combining sequencing and random forest analyses. Soil cumulative N2O emissions significantly increased with soil pH in all agricultural soils. However, they decreased with soil organic carbon (SOC) in alkaline soils. Nitrapyrin significantly inhibited soil cumulative N2O emissions and AOB growth, with a significant inhibition of the AOB Nitrosospira cluster 3a.2 (D11) abundance. One Nitrosospira multiformis-like OTU phylotype (OTU34), which was classified within the AOB Nitrosospira cluster 3a.2 (D11), had the greatest importance on cumulative N2O emissions and its growth significantly depended on soil pH and SOC contents, with higher growth at high pH and low SOC conditions. Collectively, our results demonstrate that alkaline soils with low SOC contents have high N2O emissions, which were mainly driven by AOB Nitrosospira cluster 3a.2 (D11). Nitrapyrin can efficiently reduce nitrification-related N2O emissions by inhibiting the activity of AOB Nitrosospira cluster 3a.2 (D11). This study advances our understanding of key nitrifiers responsible for high N2O emissions in agricultural soils and their controlling factors, and provides vital knowledge for N2O emission mitigation in agricultural ecosystems.


Assuntos
Ecossistema , Solo , Solo/química , Amônia/química , Carbono , Oxirredução , Archaea , Nitrificação , Microbiologia do Solo
3.
Cell Mol Neurobiol ; 43(6): 2557-2566, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36952071

RESUMO

Chronic cerebral ischaemia (CCI) is a high-incidence cardiovascular and cerebrovascular disease that is very common in clinical practice. Although many pathogenic mechanisms have been explored, there is still great controversy among neuroscientists regarding the pathogenesis of CCI. Therefore, it is important to elucidate the mechanisms of CCI occurrence and progression for the prevention and treatment of ischaemic cerebrovascular disorders. Autophagy and inflammation play vital roles in CCI, but the relationship between these two processes in this disease remains unknown. Here, we review the progression and discuss the functions, actions and pathways of autophagy and inflammation in CCI, including a comprehensive view of the transition from acute disease to CCI through ischaemic repair mechanisms. This review may provide a reference for future research and treatment of CCI. Schematic diagram of the interplay between autophagy and inflammation in CCI. CCI lead to serious, life-threatening complications. This review summarizes two factors in CCI, including autophagy and inflammation, which have been focused for the mechanisms of CCI. In short, the possible points of intersection are shown in the illustration. CCI, Chronic cerebral ischaemia; ER stress, Endoplasmic reticulum stress; ROS, Reactive oxygen species.


Assuntos
Isquemia Encefálica , Estresse do Retículo Endoplasmático , Humanos , Isquemia Encefálica/complicações , Inflamação/patologia , Autofagia , Isquemia
4.
J Asian Nat Prod Res ; 25(9): 842-848, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36562123

RESUMO

Further investigation on the roots of Aconitum weixiense led to the isolation of two new bis-diterpenoid alkaloids, named as weisaconitines E and F (1-2), which were elucidated by IR, HR-ESI-MS, 1D- and 2D-NMR analyses. Their structures are characterized as denudatine-atisine-type bis-diterpenoid alkaloids.


Assuntos
Aconitum , Alcaloides , Diterpenos , Medicamentos de Ervas Chinesas , Aconitum/química , Estrutura Molecular , Alcaloides/química , Medicamentos de Ervas Chinesas/química , Diterpenos/química , Raízes de Plantas/química
5.
New Phytol ; 234(6): 1977-1986, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34921429

RESUMO

Plants form complex interaction networks with diverse microbiomes in the environment, and the intricate interplay between plants and their associated microbiomes can greatly influence ecosystem processes and functions. The phyllosphere, the aerial part of the plant, provides a unique habitat for diverse microbes, and in return the phyllosphere microbiome greatly affects plant performance. As an open system, the phyllosphere is subjected to environmental perturbations, including global change, which will impact the crosstalk between plants and their microbiomes. In this review, we aim to provide a synthesis of current knowledge of the complex interactions between plants and the phyllosphere microbiome under global changes and to identify future priority areas of research on this topic.


Assuntos
Microbiota , Plantas
6.
Cell Biol Int ; 46(12): 2207-2219, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36153644

RESUMO

Sepsis is a life-threatening condition, and treatment for sepsis in clinic is often not available, partially due to insufficient understanding of the pathogenesis of sepsis. Extensive study to elucidate the pathogenesis is required to improve the clinical management and outcome of sepsis. In this study, we investigated the pathogenesis of sepsis using peripheral blood mononuclear cells (PBMCs) from septic patients and studied the underlying mechanism of miR-16-5p on aerobic glycolysis in lipopolysaccharide (LPS)-treated THP1 and Raw264.7 cells. The levels of RNA and protein were determined by real-time quantitative PCR and immunoblotting assay, respectively. The production of high mobility group box 1 (HMGB1) was measured by enzyme-linked immunosorbent assay. The levels of succinate and lactate were determined using colorimetric kits. The extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) were measured by extracellular flux analyzer. The results showed that the expression of miR-16-5p was elevated, while sirtuin 3 (SIRT3) was decreased in PBMCs from septic patients and LPS-treated cells, along with accumulation of acetylated succinate dehydrogenase complex, subunit A. Concomitantly, an increase in HMGB1, succinate, lactate, as well as ECAR and a decrease in OCR were observed. Knockdown of miR-16-5p upregulated SIRT3 expression, facilitated SDHA deacetylation, and attenuated sepsis-related aerobic glycolysis. Further study identified that SIRT3 is targeted by miR-16-5p, and overexpression of SIRT3 rescued LPS-induced responses via deacetylation of SDHA. Our findings revealed a novel miR-16-5p-regulated SIRT3-SDHA axis in sepsis and provided novel insights for sepsis treatment.


Assuntos
Proteína HMGB1 , MicroRNAs , Sepse , Sirtuína 3 , Humanos , Sirtuína 3/genética , Sirtuína 3/metabolismo , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Leucócitos Mononucleares/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Sepse/genética , Glicólise , Lactatos , Succinatos , Apoptose , Complexo II de Transporte de Elétrons/metabolismo
7.
Neuroimmunomodulation ; 29(4): 468-475, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35760053

RESUMO

PURPOSE: We report two cases diagnosed as acute necrotizing encephalopathy (ANE) with acute onset and various clinical manifestations. METHODS: The patients' data were obtained from the medical records of the Binzhou Medical University Hospital in Binzhou, China. The clinical symptoms, laboratory examination, neuroimaging, treatment, and prognosis of the 2 patients were collected and analyzed. RESULTS: We report 2 adult ANE patients with acute onset. The first symptom was fever, followed by symptoms and signs of damage to the central nervous system. The patients were infected with herpes simplex virus and influenza virus, respectively. The main manifestation on brain magnetic resonance imaging was a mixed-signal of a "three-layer structure" in the bilateral thalamus. The first patient died. Based on the experience of the diagnosis and treatment of the first patient, combined with a review of the literature, the second patient was immediately treated with glucocorticoid pulse therapy combined with gamma globulin injection. This patient's condition was controlled, and the prognosis was good. CONCLUSIONS: This study describes the clinical symptoms, laboratory examination, neuroimaging evidence, and treatment experience of ANE in adults. We believe that the progress of the disease may be controlled, and the prognosis may be improved if glucocorticoid pulse therapy combined with gamma globulin injection is used as soon as possible.


Assuntos
Encefalopatias , Glucocorticoides , Humanos , Adulto , Encefalopatias/diagnóstico , Encefalopatias/patologia , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , gama-Globulinas
8.
Environ Microbiol ; 23(2): 588-599, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32249528

RESUMO

Viruses can affect microbial dynamics, metabolism and biogeochemical cycles in aquatic ecosystems. However, viral diversity and functions in agricultural soils are poorly known, especially in the rhizosphere. We used virome analysis of eight rhizosphere and bulk soils to study viral diversity and potential biogeochemical impacts in an agro-ecosystem. The order Caudovirales was the predominant viral type in agricultural soils, with Siphoviridae being the most abundant family. Phylogenetic analysis of the terminase large subunit of Caudovirales identified high viral diversity and three novel groups. Viral community composition differed significantly between bulk and rhizosphere soils. Soil pH was the main environmental driver of the viral community structure. Remarkably, abundant auxiliary carbohydrate-active enzyme (CAZyme) genes were detected in viromes, including glycoside hydrolases, carbohydrate esterases and carbohydrate-binding modules. These results demonstrate that virus-encoded putative auxiliary metabolic genes or metabolic genes that may change bacterial metabolism and indirectly contribute to biogeochemical cycling, especially carbon cycling, in agricultural soil.


Assuntos
Biodiversidade , Microbiologia do Solo , Vírus/isolamento & purificação , Agricultura , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Ecossistema , Concentração de Íons de Hidrogênio , Filogenia , Rizosfera , Solo/química , Vírus/classificação , Vírus/genética
9.
Environ Microbiol ; 23(4): 1907-1924, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32996254

RESUMO

Plants harbour highly diverse mycobiomes which sustain essential functions for host health and productivity. However, ecological processes that govern the plant-mycobiome assembly, interactions and their impact on ecosystem functions remain poorly known. Here we characterized the ecological role and community assembly of both abundant and rare fungal taxa along the soil-plant continuums (rhizosphere, phyllosphere and endosphere) in the maize-wheat/barley rotation system under different fertilization practices at two contrasting sites. Our results indicate that mycobiome assembly is shaped predominantly by compartment niche and host species rather than by environmental factors. Moreover, crop-associated fungal communities are dominated by few abundant taxa mainly belonging to Sordariomycetes and Dothideomycetes, while the majority of diversity within mycobiomes are represented by rare taxa. For plant compartments, the abundant sub-community is mainly determined by stochastic processes. In contrast, the rare sub-community is more sensitive to host selection and mainly governed by deterministic processes. Furthermore, our results demonstrate that rare taxa play an important role in fungal co-occurrence network and ecosystem functioning like crop yield and soil enzyme activities. These results significantly advance our understanding of crop mycobiome assembly and highlight the key role of rare taxa in sustaining the stability of crop mycobiomes and ecosystem functions.


Assuntos
Produtos Agrícolas/microbiologia , Micobioma , Ecossistema , Fungos/genética , Rizosfera , Microbiologia do Solo
10.
New Phytol ; 229(2): 1091-1104, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32852792

RESUMO

Plant microbiomes are essential to host health and productivity but the ecological processes that govern crop microbiome assembly are not fully known. Here we examined bacterial communities across 684 samples from soils (rhizosphere and bulk soil) and multiple compartment niches (rhizoplane, root endosphere, phylloplane, and leaf endosphere) in maize (Zea mays)-wheat (Triticum aestivum)/barley (Hordeum vulgare) rotation system under different fertilization practices at two contrasting sites. Our results demonstrate that microbiome assembly along the soil-plant continuum is shaped predominantly by compartment niche and host species rather than by site or fertilization practice. From soils to epiphytes to endophytes, host selection pressure sequentially increased and bacterial diversity and network complexity consequently reduced, with the strongest host effect in leaf endosphere. Source tracking indicates that crop microbiome is mainly derived from soils and gradually enriched and filtered at different plant compartment niches. Moreover, crop microbiomes were dominated by a few dominant taxa (c. 0.5% of bacterial phylotypes), with bacilli identified as the important biomarker taxa for wheat and barley and Methylobacteriaceae for maize. Our work provides comprehensive empirical evidence on host selection, potential sources and enrichment processes for crop microbiome assembly, and has important implications for future crop management and manipulation of crop microbiome for sustainable agriculture.


Assuntos
Microbiota , Microbiologia do Solo , Bactérias , Raízes de Plantas , Rizosfera
11.
Neoplasma ; 68(3): 602-612, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33780265

RESUMO

CCAAT enhancer-binding protein alpha (CEBPA, also known as C/EBPα) is a transcription factor that plays an essential role in regulating terminal differentiation and cell proliferation of many tissues. The objective of this study was to explore the potential function of CEBPA in ovarian cancer. The expression of CEBPA in ovarian cancer samples and adjacent normal tissues was evaluated by qRT-PCR. The putative role of CEBPA in ovarian cancer cells was evaluated by immunohistochemistry, western blot, cell viability assay, BrdU incorporation assay, soft agar colony formation assay, Transwell cell migration and invasion assay, tumor xenograft formation, and lung metastasis model. We found that CEBPA was downregulated in ovarian cancer samples and predicted a poor prognosis. CRISPR/Cas9-mediated CEBPA knockout promoted proliferation, anchorage-independent growth, migration, invasion, and EMT of ovarian cancer cells, while enforced CEPBA expression suppressed proliferation, anchorage-independent growth, migration, invasion, EMT, tumor xenograft growth, and lung metastasis of ovarian cancer cells. Furthermore, we found that the knockout of CEBPA activated Wnt/ß-catenin signaling in ovarian cancer cells, while CEBPA overexpression suppressed Wnt/ß-catenin activation. Our data indicated that CEBPA acted as a tumor suppressor in ovarian cancer, and might be a potential prognostic marker for ovarian cancer treatment.


Assuntos
Transição Epitelial-Mesenquimal , Neoplasias Ovarianas , Proteína alfa Estimuladora de Ligação a CCAAT , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Ovarianas/genética , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismo
12.
BMC Public Health ; 20(1): 957, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32552712

RESUMO

BACKGROUND: The comorbid presence of tuberculosis and diabetes mellitus has become an increasingly important public health threat to the prevention and control of both diseases. Thus, household contact investigation may serve a dual purpose of screening for both tuberculosis and diabetes mellitus among household contacts. We therefore aimed to evaluate the coverage of screening for tuberculosis and diabetes mellitus among household contacts of tuberculosis index cases and to determine predictors of tuberculosis screening. METHODS: A household-based survey was conducted in February 2019 in Muang district of Phatthalung Province, Thailand where 95 index tuberculosis patients were newly diagnosed with pulmonary or pleural tuberculosis between October 2017 and September 2018. Household contacts of the index patients were interviewed using a structured questionnaire to ascertain their past-year history of tuberculosis screening and, if appropriate, diabetes mellitus screening. For children, the household head or an adult household member was interviewed as a proxy. Coverage of tuberculosis screening at the household level was regarded as households having all contacts screened for tuberculosis. Logistic regression and mixed-effects logistic regression models were used to determine predictors of tuberculosis screening at the household and individual levels, respectively, with the strengths of association presented as adjusted odds ratios (AOR) and 95% confidence intervals (CI). RESULTS: Of 61 responding households (64%), complete coverage of tuberculosis screening at the household level was 34.4% and among the 174 household contacts was 46.6%. About 20% of contacts did not receive any recommendation for tuberculosis screening. Households were more likely to have all members screened for tuberculosis if they were advised to be screened by a healthcare professional rather than someone else. At the individual level, contacts aged ≥35 years (AOR: 30.6, 95% CI: 2.0-466.0), being an employee (AOR: 0.1, 95% CI: 0.0-0.8) and those who had lived more than 5 years in the same household (AOR: 0.1, 95% CI: 0.0-0.8) were independent predictors for tuberculosis screening. Coverage of diabetes mellitus screening was 80.6% with lack of awareness being the main reason for not being screened. CONCLUSIONS: Compared to diabetes screening, the coverage of tuberculosis screening was low. A better strategy to improve coverage of tuberculosis contact screening is needed.


Assuntos
Busca de Comunicante/estatística & dados numéricos , Diabetes Mellitus/diagnóstico , Características da Família , Programas de Rastreamento/estatística & dados numéricos , Tuberculose/diagnóstico , Adolescente , Adulto , Idoso , Criança , Estudos Transversais , Diabetes Mellitus/prevenção & controle , Feminino , Humanos , Lactente , Modelos Logísticos , Masculino , Razão de Chances , Avaliação de Processos e Resultados em Cuidados de Saúde , Fatores de Risco , Inquéritos e Questionários , Tailândia , Tuberculose/prevenção & controle
13.
Sheng Li Xue Bao ; 72(4): 449-454, 2020 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-32820307

RESUMO

The paper was aimed to explore the role of serum exosomes induced by hepatic ischemia/reperfusion (I/R) injury in the damage of hippocampus and cerebral cortex of rats. The male Sprague-Dawley (SD) rats were randomly divided into 4 groups: sham operation group (S), hepatic I/R injury group (I/R), serum exosomes from S group treatment group (ES) and serum exosomes from I/R group treatment group (EI). In ES group and EI group, 100 µL serum exosomes from S group and I/R group were injected into the normal rats through tail vein respectively. Another three normal rats were injected intravenously with serum exosomes labeled with PKH26 red fluorescence, and then the expression of fluorescence in the brain tissues was observed by immunofluorescence microscope. The morphology and size of exosomes were observed by transmission electron microscope, the expression of exosomes markers CD63 and CD9 was detected by Western blot, and the damage of liver and brain, levels of apoptosis and oxidative stress response in hippocampus and cerebral cortex were observed by serological and histological indexes. The results showed that the exosomes were a group of round or ovoid membranous vesicles, sized in 30-100 nm. Compared with that in S group, the content of serum exosomes in I/R group was increased (P < 0.05). Moreover, serum exosomes could go through the blood-brain barrier and enter the brain tissue freely through blood circulation. The index of liver function in I/R group was significantly higher than that in S group (P < 0.05). There was no significance in the degree of brain damage, apoptosis and oxidative stress in hippocampus and cerebral cortex between S group and ES group. Compared with those in S group and ES group, the serum levels of brain injury markers, apoptosis index (AI) and oxidative stress in hippocampus and cerebral cortex increased in I/R group and EI group (P < 0.05). Whereas, compared with those in I/R group, the above indicators in EI group decreased (P < 0.05). Therefore, hepatic I/R injury can lead to the damage of hippocampus and cerebral cortex, and the increased serum exosomes induced by hepatic I/R plays an important role.


Assuntos
Isquemia Encefálica , Exossomos , Traumatismo por Reperfusão , Animais , Hipocampo , Fígado , Masculino , Ratos , Ratos Sprague-Dawley
14.
Small ; 15(21): e1804651, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30990971

RESUMO

Fabricating a strain sensor that can detect large deformation over a curved object with a high sensitivity is crucial in wearable electronics, human/machine interfaces, and soft robotics. Herein, an ionogel nanocomposite is presented for this purpose. Tuning the composition of the ionogel nanocomposites allows the attainment of the best features, such as excellent self-healing (>95% healing efficiency), strong adhesion (347.3 N m-1 ), high stretchability (2000%), and more than ten times change in resistance under stretching. Furthermore, the ionogel nanocomposite-based sensor exhibits good reliability and excellent durability after 500 cycles, as well as a large gauge factor of 20 when it is stretched under a strain of 800-1400%. Moreover, the nanocomposite can self-heal under arduous conditions, such as a temperature as low as -20 °C and a temperature as high as 60 °C. All these merits are achieved mainly due to the integration of dynamic metal coordination bonds inside a loosely cross-linked network of ionogel nanocomposite doped with Fe3 O4 nanoparticles.

15.
J Environ Manage ; 237: 552-559, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30826636

RESUMO

Bioremediation programs of cadmium (Cd) by microorganisms have being proposed, but the underlying mechanism of the remediation ion remains unexplored. Here, the sorption efficiency and subcellular fraction distribution of Cd in three selected microbial species were investigated. Our results showed that both species of the microorganisms and initial Cd concentrations strongly affected the Cd sorption capacity. In the three microbial species, the Cd removal efficiency increased with decreased Cd concentrations. Specifically, Hansenula anomala removed the highest Cd ions in low concentration of 0.05 mg L-1; while in medium concentration of 0.5 mg L-1 and high concentration of 5 mg L-1, Bacillus subtilis removed the highest Cd ions. The subcellular fractionation allocation showed that Cd was mainly allocated on cell wall (mantle and inner wall) in Pseudomonas stutzeri and B. subtilis, while cell cytomembrane accumulated similar amount of Cd compared to the cell wall of H. anomala at concentration of 0.5 mg L-1. Meanwhile, the Cd distributions on cell subcellular fractionation of the three species changed along the contact times, suggesting varied migration models during the biosorption process. Moreover, the functional groups involved in biosorption differed among the species based on Fourier Transform Infrared (FTIR) analysis. Our results have important implications for developing and improving Cd remediation by microorganisms, which is a low-cost and environmentally friendly bioremediation strategy of Cd pollution in environments.


Assuntos
Cádmio , Poluentes Químicos da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética
16.
Zhongguo Zhong Yao Za Zhi ; 44(4): 774-780, 2019 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30989891

RESUMO

In this experiment,the antioxidant capacity of raspberry extract and the protective effect on liver injury induced by ConA in mice were investigated. Balb/C male mice were randomly divided into six groups: normal group,model group,bicyclol control group( 200 mg·kg~(-1)),low-dose raspberry extract group( 200 mg·kg~(-1)),middle-dose raspberry extract group( 400 mg·kg~(-1)),and highdose raspberry extract group( 800 mg·kg~(-1)). Each group was intragastrically administered with drugs according to the body weight once a day. Seven days later,all of the groups except for the normal group were treated with ConA( 20 mg·kg~(-1)) through tail vein injection to establish the acute liver injury model. The mice were put to death 8 hours later. The organ indexes were calculated. These rum levels of ALT,AST and LDH and the activities of SOD,CAT,GSH and MDA in liver tissue were detected. HE staining was used to observe the pathological changes of liver tissue in mice. Western blot was used to detect the expressions of Bax,Bcl-2,Nrf2 and Keap-1. The antioxidant capacity of raspberry extract was measured by CAA assay. The results showed that,raspberry extract had a strong antioxidant capacity. Simultaneously,compared with the model group,raspberry extract can significantly improve the pathological conditions of liver,and significantly reduce ALT,AST and LDH activities in serum of liver injury mice( P<0. 01). The activities of SOD,CAT in liver homogenate supernatant were significantly increased in the high-dose group,the content of GSH increased,while the content of MDA was sharply declined in the high-dose group( P<0. 01). Meanwhile,raspberry extract down-regulated the expressions of Bax and Keap-1 and up-regulated the expressions of Bcl-2 and Nrf2. CAA showed that the compound raspberry extract had a strong antioxidant capacity. Therefore,raspberry extract has an obvious protective effect on acute liver injury induced by ConA in mice.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Rubus , Animais , Antioxidantes , Fígado , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Substâncias Protetoras
17.
Environ Microbiol ; 20(8): 2834-2853, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29687546

RESUMO

Terrestrial-marine boundaries are significant sites of biogeochemical activity with delineated gradients from land to sea. While niche differentiation of ammonia-oxidizing archaea (AOA) and bacteria (AOB) driven by pH and nitrogen is well known, the patterns and environmental drivers of AOA and AOB community structure and activity across soil-sediment boundaries have not yet been determined. In this study, nitrification potential rate, community composition and transcriptional activity of AOA and AOB in soil, soil/sediment interface and sediments of two coastal Bays were characterized using a combination of field investigations and microcosm incubations. At DNA level, amoA gene abundances of AOA were significantly greater than AOB in soil, while in sediments AOB were significantly more abundant than AOA, but at the soil/sediment interface there were equal numbers of AOA and AOB amoA genes. Microcosm incubations provided further evidence, through qPCR and DGGE-sequencing analysis of amoA transcripts, that AOA were active in soil, AOB in sediment and both AOA and AOB were active at the soil/sediment interface. The AOA and AOB community composition shifted across the coastal soil-interface-sediment gradient with salinity and pH identified as major environmental drivers.


Assuntos
Amônia/metabolismo , Archaea/metabolismo , Bactérias/metabolismo , Baías , Microbiologia do Solo , Archaea/genética , Bactérias/genética , Ecossistema , Nitrificação , Nitrogênio/análise , Oxirredução , Salinidade , Solo/química
18.
Microb Ecol ; 75(2): 375-386, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28825127

RESUMO

A substantial gap remains in our understanding of the abundance, diversity, and ecology of viruses in soil although some advances have been achieved in recent years. In this study, four soil samples according to the salinity gradient from shore to inland in East China have been characterized. Results showed that spherical virus particles represented the largest viral component in all of the four samples. The viromes had remarkably different taxonomic compositions, and most of the sequences were derived from single-stranded DNA viruses, especially from families Microviridae and Circoviridae. Compared with viromes from other aquatic and sediment samples, the community compositions of our four soil viromes resembled each other, meanwhile coastal sample virome closely congregated with sediment and hypersaline viromes, and high salinity paddy soil sample virome was similar with surface sediment virome. Phylogenetic analysis of functional genes showed that four viromes have high diversity of the subfamily Gokushovirinae in family Microviridae and most of Circoviridae replicase protein sequences grouped within the CRESS-DNA viruses. This work provided an initial outline of the viral communities in marine-terrestrial ecotone and will improve our understanding of the ecological functions of soil viruses.


Assuntos
Biodiversidade , Vírus de DNA/isolamento & purificação , Microbiologia do Solo , China , Vírus de DNA/classificação , Vírus de DNA/genética , Ecossistema , Filogenia , Salinidade , Solo/química
19.
Microb Ecol ; 75(4): 1009-1023, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29124311

RESUMO

Climate change is projected to have impacts on precipitation and temperature regimes in drylands of high elevation regions, with especially large effects in the Qinghai-Tibetan Plateau. However, there was limited information about how the projected climate change will impact on the soil microbial community and their activity in the region. Here, we present results from a study conducted across 72 soil samples from 24 different sites along a temperature and precipitation gradient (substituted by aridity index ranging from 0.079 to 0.89) of the Plateau, to assess how changes in aridity affect the abundance, community composition, and diversity of bacteria, ammonia-oxidizers, and denitrifers (nirK/S and nosZ genes-containing communities) as well as nitrogen (N) turnover enzyme activities. We found V-shaped or inverted V-shaped relationships between the aridity index (AI) and soil microbial parameters (gene abundance, community structures, microbial diversity, and N turnover enzyme activities) with a threshold at AI = 0.27. The increasing or decreasing rates of the microbial parameters were higher in areas with AI < 0.27 (alpine steppes) than in mesic areas with 0.27 < AI < 0.89 (alpine meadow and swamp meadow). The results indicated that the projected warming and wetting have a strong impact on soil microbial communities in the alpine steppes.


Assuntos
Mudança Climática , Pradaria , Microbiota/genética , Microbiota/fisiologia , Microbiologia do Solo , Solo/química , Amônia/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Proteínas de Bactérias/genética , Biodiversidade , DNA Bacteriano/genética , Desnitrificação/genética , Monitoramento Ambiental , Ativação Enzimática , Ensaios Enzimáticos , Genes Bacterianos/genética , Nitrificação/genética , Nitrogênio/metabolismo , Ciclo do Nitrogênio , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Temperatura , Tibet
20.
J Clin Lab Anal ; 31(2)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27500554

RESUMO

BACKGROUND: We aimed to investigate the correlations between ACE2 polymorphisms and type 2 diabetes mellitus (T2DM) combined with cerebral stroke (CS). METHODS: A total of 346 patients treated or hospitalized in our hospital were enrolled, including 181 cases without cerebrovascular complications (T2DM group) and 165 cases combined with CS (T2DM + CS group); 284 healthy individuals were selected as the control group. PCR-RFLP and ELISA were used to analyze ACE2 G8790A polymorphisms and serum ACE2 levels, respectively. RESULTS: Significant differences were observed in the genotype/allele frequency of ACE2 G8790A between the T2DM + CS and control groups, and the T2DM and T2DM + CS groups, and in the genotype frequency of ACE2 G8790A between the T2DM and the control groups. The A allele may increase the risk of T2DM combined with CS. The AA genotype may also increase the risk of T2DM combined with CS (OR = 3.733, 95%CI = 2.069-6.738; OR = 3.597, 95%CI = 1.884-6.867). Serum ACE2 levels showed statistically significant differences among the groups. Systolic pressure and diastolic pressure were protective factors of T2DM combined with CS. CONCLUSION: The ACE2 G8790A polymorphism in T2DM patients was correlated with CS, and the A allele might be a risk factor of T2DM combined with CS.


Assuntos
Diabetes Mellitus Tipo 2/genética , Peptidil Dipeptidase A/sangue , Peptidil Dipeptidase A/genética , Polimorfismo de Nucleotídeo Único/genética , Acidente Vascular Cerebral/genética , Enzima de Conversão de Angiotensina 2 , Pressão Sanguínea , Diabetes Mellitus Tipo 2/sangue , Ensaio de Imunoadsorção Enzimática , Frequência do Gene/genética , Genótipo , Humanos , Polimorfismo de Fragmento de Restrição , Fatores de Risco , Acidente Vascular Cerebral/sangue
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