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1.
J Vis Exp ; (197)2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37590509

RESUMO

Tui Na or massage therapy alleviates symptoms related to intervertebral disc degeneration (IDD). However, precise, repeatable, standardized instructions for Tuina manipulation are lacking. This study establishes IDD model rabbits induced by fibrous ring puncture, creates targeted Tuina stimulation protocols at the acupuncture points in the lumbar region, and describes in detail the operation methods and requirements of kneading, pointing, and flicking. New Zealand male white rabbits (n = 15) were selected and randomly divided into a blank group, a model group, and a Tuina group. The rabbits in the model group and the Tuina group were molded by fibrous ring puncture; the rabbits in the model group were only immobilized on the operating table without treatment. In contrast, the Tuina group used the "8N/10N, 30 cycles/min" prescription for kneading, pointing, and flicking to perform the intervention, using tactile sensory aids to monitor and regulate the intensity of the Tuina operation. Imaging diagnosis and pathological tests were used to assess the effect of Tuina in rabbits, and the results showed improved imaging features and significantly lowered pathology scores of lumbar disc degeneration in the Tuina group compared to the model group (P < 0.01). Targeted Tuina in the lumbar region may be beneficial in the alleviation of lumbar disc degeneration, but further verification is needed. By regularly performing Tuina and recording the mechanical information involved enables reproducible manipulation prescriptions and helps to observe the basic features of the underlying mechanism of Tuina for IDD.


Assuntos
Terapia por Acupuntura , Degeneração do Disco Intervertebral , Animais , Masculino , Coelhos , Degeneração do Disco Intervertebral/terapia , Região Lombossacral , Massagem , Punção Espinal
2.
Adv Sci (Weinh) ; 10(27): e2207108, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37469011

RESUMO

Systemic lupus erythematosus (SLE) is a complex autoimmune disease with abnormal activation of the immune system. Recent attention is increasing about how aberrant lipid and cholesterol metabolism is linked together with type I interferon (IFN-I) signaling in the regulation of the pathogenesis of SLE. Here, a metabonomic analysis is performed and increased plasma concentrations of oxysterols, especially 7α, 25-dihydroxycholesterol (7α, 25-OHC), are identified in SLE patients. The authors find that 7α, 25-OHC binding to its receptor Epstein-Barr virus-induced gene 2 (EBI2) in macrophages can suppress STAT activation and the production of IFN-ß, chemokines, and cytokines. Importantly, monocytes/macrophages from SLE patients and mice show significantly reduced EBI2 expression, which can be triggered by IFN-γ produced in activated T cells. Previous findings suggest that EBI2 enhances immune cell migration. Opposite to this effect, the authors demonstrate that EBI2-deficient macrophages produce higher levels of chemokines and cytokines, which recruits and activates myeloid cells,T and B lymphocytes to exacerbate tetramethylpentadecane-induced SLE. Together, via sensing the oxysterol 7α, 25-OHC, EBI2 in macrophages can modulate innate and adaptive immune responses, which may be used as a potential diagnostic marker and therapeutic target for SLE.


Assuntos
Infecções por Vírus Epstein-Barr , Lúpus Eritematoso Sistêmico , Oxisteróis , Animais , Humanos , Camundongos , Imunidade Adaptativa , Citocinas/metabolismo , Herpesvirus Humano 4 , Hidroxicolesteróis/metabolismo , Hidroxicolesteróis/farmacologia , Receptores Acoplados a Proteínas G/genética
3.
Cell Rep ; 42(5): 112489, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37167063

RESUMO

Upon recognizing danger signals produced by virally infected neurons, macrophages in the central nervous system (CNS) secrete multiple inflammatory cytokines to accelerate neuron apoptosis. The understanding is limited about which key effectors regulate macrophage-neuron crosstalk upon infection. We have used neurotropic-virus-infected murine models to identify that vascular endothelial growth factor receptor 3 (VEGFR-3) is upregulated in the CNS macrophages and that virally infected neurons secrete the ligand VEGF-C. When cultured with VEGF-C-containing supernatants from virally infected neurons, VEGFR-3+ macrophages suppress tumor necrosis factor α (TNF-α) secretion to reduce neuron apoptosis. Vegfr-3ΔLBD/ΔLBD (deletion of ligand-binding domain in myeloid cells) mice or mice treated with the VEGFR-3 kinase inhibitor exacerbate the severity of encephalitis, TNF-α production, and neuron apoptosis post Japanese encephalitis virus (JEV) infection. Activating VEGFR-3 or blocking TNF-α can reduce encephalitis and neuronal damage upon JEV infection. Altogether, we show that the inducible VEGF-C/VEGFR-3 module generates protective crosstalk between neurons and macrophages to alleviate CNS viral infection.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Camundongos , Animais , Fator de Necrose Tumoral alfa/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Fator C de Crescimento do Endotélio Vascular/metabolismo , Ligantes , Fator A de Crescimento do Endotélio Vascular/metabolismo , Encefalite Japonesa/metabolismo , Encefalite Japonesa/patologia , Vírus da Encefalite Japonesa (Espécie)/metabolismo , Neurônios/metabolismo , Macrófagos/metabolismo
4.
Phytother Res ; 37(5): 1771-1786, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36444395

RESUMO

Triple-negative breast cancer (TNBC) accounts for 10-20% of all human ductal adenocarcinomas and has a poor prognosis relative to other subtypes because of its high propensity to develop metastases. Here, the anticancer effects of asiaticoside (AC) against TNBC and the possible underlying mechanism were examined. We found that AC inhibited the TGF-ß1 expression and the SMAD2/3 phosphorylation in TNBC cells, thereby impairing the TGF-ß/SMAD signaling. AC inhibited the migration, invasion, and epithelial-mesenchymal transition (EMT) of TNBC cells by suppressing the TGF-ß/SMAD signaling. Meanwhile, AC inhibited the lung metastasis of TNBC cells in vivo and the expression of p-SMAD2/3 and vimentin, and increased the expression of E-cadherin and ZO-1 in the lung. Peroxisome proliferator activated receptor gamma (PPARG) was identified as a potential target of AC. AC increased PPARG expression, while PPARG knockdown attenuated the therapeutic effect of AC. AC-mediated PPARG overexpression suppressed the transcription of P2X purinoceptor 7 (P2RX7). The restoration of P2RX7 reversed the therapeutic effect of AC. These results suggested that AC blocked P2RX7-mediated TGF-ß/SMAD signaling by increasing PPARG expression, thereby suppressing EMT in TNBC.


Assuntos
PPAR gama , Neoplasias de Mama Triplo Negativas , Humanos , PPAR gama/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Transição Epitelial-Mesenquimal , Linhagem Celular Tumoral , Receptores Purinérgicos P2X7/uso terapêutico
5.
Front Oncol ; 12: 949058, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36237316

RESUMO

Objectives: Clear cell renal cell carcinoma (ccRCC) is highly prevalent, prone to metastasis, and has a poor prognosis after metastasis. Therefore, this study aimed to develop a prognostic model to predict the individualized prognosis of patients with metastatic clear cell renal cell carcinoma (mccRCC). Patients and Methods: Data of 1790 patients with mccRCC, registered from 2010 to 2015, were extracted from the Surveillance, Epidemiology and End Results (SEER) database. The included patients were randomly divided into a training set (n = 1253) and a validation set (n = 537) based on the ratio of 7:3. The univariate and multivariate Cox regression analyses were used to identify the important independent prognostic factors. A nomogram was then constructed to predict cancer specific survival (CSS). The performance of the nomogram was internally validated by using the concordance index (C-index), calibration plots, receiver operating characteristic curves, net reclassification improvement (NRI), integrated discrimination improvement (IDI), and decision curve analysis (DCA). We compared the nomogram with the TNM staging system. Kaplan-Meier survival analysis was applied to validate the application of the risk stratification system. Results: Diagnostic age, T-stage, N-stage, bone metastases, brain metastases, liver metastases, lung metastases, chemotherapy, radiotherapy, surgery, and histological grade were identified as independent predictors of CSS. The C-index of training and validation sets are 0.707 and 0.650 respectively. In the training set, the AUC of CSS predicted by nomogram in patients with mccRCC at 1-, 3- and 5-years were 0.770, 0.758, and 0.757, respectively. And that in the validation set were 0.717, 0.700, and 0.700 respectively. Calibration plots also showed great prediction accuracy. Compared with the TNM staging system, NRI and IDI results showed that the predictive ability of the nomogram was greatly improved, and DCA showed that patients obtained clinical benefits. The risk stratification system can significantly distinguish the patients with different survival risks. Conclusion: In this study, we developed and validated a nomogram to predict the CSS rate in patients with mccRCC. It showed consistent reliability and clinical applicability. Nomogram may assist clinicians in evaluating the risk factors of patients and formulating an optimal individualized treatment strategy.

6.
Front Neurosci ; 16: 1098311, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36711149

RESUMO

Background: Most previous studies on acupuncture in the treatment of knee osteoarthritis (KOA) have focused on improving functional efficacy and safety, while related mechanisms have not been systematically reviewed. Acupuncture modulates cytokines to attenuate cartilage extracellular matrix degradation and apoptosis, key to the pathogenesis of KOA, but the mechanisms are complex. Objectives: The purpose of this study is to assess the efficacy of acupuncture quantitatively and summarily in animal studies of KOA. Methods: Nine databases including PubMed, Embase, Web of Science (including Medline), Cochrane library, Scopus, CNKI, Wan Fang, and VIP were searched to retrieve animal studies on acupuncture interventions in KOA published since the inception of the journal. Relevant literature was screened, and information extracted. Meta-analysis was performed using Revman 5.4 and Stata 17.0 software. Results: The 35 included studies involved 247 animals, half of which were in acupuncture groups and half in model groups. The mean quality level was 6.7, indicating moderate quality. Meta-analysis showed that acupuncture had the following significant effects on cytokine levels in p38MAPK and mitochondrial pathways: (1) p38MAPK pathway: It significantly inhibits p38MAPK, interleukin-1beta (IL-1ß), tumor necrosis factor alpha (TNF-α), phosphorylated (p)-p38MAPK, matrix metalloproteinase-13 (MMP-13), MMP-1, a disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMST-5) expression, and significantly increased the expression of collagen II and aggrecan. (2) mitochondrial pathway: It significantly inhibited the expression of Bcl-2-associated X protein (Bax), cysteine protease-3 (caspase-3), caspase-9, and Cytochrome-c (Cyt-c). And significantly increased the expression of B cell lymphocytoma-2 (Bcl-2). In addition, acupuncture significantly reduced chondrocyte apoptosis, Mankin's score (a measure of cartilage damage), and improved cartilage morphometric characteristics. Conclusion: Acupuncture may inhibit cytokine expression in the p38MAPK pathway to attenuate cartilage extracellular matrix degradation, regulate cytokines in the mitochondrial pathway to inhibit chondrocyte apoptosis, and improve cartilage tissue-related phenotypes to delay cartilage degeneration. These findings provide possible explanations for the therapeutic mechanisms and clinical benefits of acupuncture for KOA. Systematic review registration: https://inplasy.com, identifier INPLASY20 2290125.

7.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34244427

RESUMO

Although inflammation is critical for the clearance of pathogens, uncontrolled inflammation also contributes to the development of multiple diseases such as cancer and sepsis. Since NF-κB-mediated transactivation in the nucleus is pivotal downstream of various stimuli to induce inflammation, searching the nuclear-localized targets specifically regulating NF-κB activation will provide important therapeutic application. Here, we have identified that homeodomain-interacting protein kinase 2 (HIPK2), a nuclear serine/threonine kinase, increases its expression in inflammatory macrophages. Importantly, HIPK2 deficiency or overexpression could enhance or inhibit inflammatory responses in LPS-stimulated macrophages, respectively. HIPK2-deficient mice were more susceptible to LPS-induced endotoxemia and CLP-induced sepsis. Adoptive transfer of Hipk2+/- bone marrow cells (BMs) also aggravated AOM/DSS-induced colorectal cancer. Mechanistically, HIPK2 bound and phosphorylated histone deacetylase 3 (HDAC3) at serine 374 to inhibit its enzymatic activity, thus reducing the deacetylation of p65 at lysine 218 to suppress NF-κB activation. Notably, the HDAC3 inhibitors protected wild-type or Hipk2-/- BMs-reconstituted mice from LPS-induced endotoxemia. Our findings suggest that the HIPK2-HDAC3-p65 module in macrophages restrains excessive inflammation, which may represent a new layer of therapeutic mechanism for colitis-associated colorectal cancer and sepsis.


Assuntos
Colite/complicações , Neoplasias Colorretais/etiologia , Histona Desacetilases/metabolismo , NF-kappa B/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Sepse/etiologia , Acetilação , Animais , Ceco/patologia , Neoplasias Colorretais/metabolismo , Citocinas/biossíntese , Endotoxemia/complicações , Inibidores de Histona Desacetilases/farmacologia , Humanos , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Ligadura , Lipopolissacarídeos , Lisina/metabolismo , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Fosforilação/efeitos dos fármacos , Fosfosserina/metabolismo , Punções , Sepse/metabolismo , Receptor 4 Toll-Like/metabolismo , Receptor Toll-Like 9/metabolismo , Fator de Transcrição RelA/metabolismo , Regulação para Cima
8.
Opt Express ; 28(17): 24550-24559, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32906994

RESUMO

Soliton buildup dynamics in ultrafast fiber lasers are one of the most significant topics in both the fundamental and industrial fields. In this work, by using the dispersive Fourier transformation technique, the real-time spectral evolution of soliton buildup dynamics were investigated in the all-polarization-maintaining Yb-doped fiber laser, which is mode-locked by nonlinear polarization evolution technique through the cross splicing method. It was experimentally confirmed that the same stable soliton state could be achieved through different soliton starting processes because of the initial random noises. In one case, the maximum pulse energy during the soliton starting process could reach ∼15 times the stable pulse energy, which results in the spectral chaotic state and temporal shift. We also provide another soliton buildup case with the same cavity parameters, which illustrates more moderate evolution. It involves smaller energy variation and no complex transition state. These results would deepen our understanding of soliton buildup dynamics and be beneficial for the applications of ultrafast fiber lasers.

9.
ACS Omega ; 5(25): 15353-15361, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32637809

RESUMO

Four deep eutectic solvents (DESs) were synthesized, and 5-30% polyethylenimine (PEI) was added to make functional DESs (FDESs) for dynamic absorption experiments of hydrogen sulfide. The synthesized FDESs were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and nuclear magnetic resonance. The results demonstrated the successful synthesis of FDESs. The interaction between H2S and the FDESs was discussed at a molecular level via the quantum chemical calculations. It was noticed that FDESs prefer chemisorption on H2S. In this work, the 25% PEI/FDES@EG showed the highest desulfurization performance. The effects of H2S concentration and temperature on the desulfurization performance were investigated. It was found that a relatively low temperature (30 °C) was favorable for the absorption of H2S. The 25% PEI/FDES@EG could remove H2S efficiently over a low H2S concentration. Moisture played an important role in the FDES desulfurization system. The absorption/desorption cycle experiment indicated that the FDESs retain their good regeneration performance for at least five times.

10.
Sensors (Basel) ; 19(24)2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31847492

RESUMO

Lunar surface temperature is one of the fundamental thermophysical parameters of the lunar regolith, which is of great significance to the interpretation of remote-sensing thermal data. In this study, a daytime surface temperature model is established focusing on the lunar superficial layer with high spatial-temporal resolution. The physical parameters at the time of interest are adopted, including effective solar irradiance, lunar libration, large-scale topographic shading, and surrounding diffuse reflection. Thereafter, the 1/64° temperature distributions at five local times are quantitatively generated and analyzed in Sinus Iridum. Also, combined with Chang'E-2 microwave radiometer (CELMS) data and Diviner thermal infrared (TIR) data, the spectral emissivity distributions are estimated as a potential geological application of the simulated surface temperature. The results are as follows: (1) daytime surface temperature in Sinus Iridum is significantly affected by the local topography and observation time, and the influence of diffuse reflection energy is obvious; (2) the emissivity distributions provide a new way to understand the thermophysical properties difference of lunar regolith at different depths; (3) the influence of lunar orbiting revolution and precession on surface temperature should be analyzed carefully, which shows the importance of using the parameters at the time of interest.

11.
AMB Express ; 8(1): 103, 2018 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-29936673

RESUMO

The slpB gene of Lactobacillus acidophilus NCFM, which differs from the slpA gene and is silent under normal conditions, was successfully amplified and ligated to the corresponding available sites on a recombinant pET-28a vector. Then the pET-28a-slpB vector was transformed into Escherichia coli DH (DE3) and the fusion His-slpB protein was expressed by induction with 1 mM IPTG for 14 h at 37 °C. The resulting His-slpB protein (SB) had a relative molecular weight of 48 kDa. It was purified using a Ni-NTA column and was confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western blot contrastive analysis. The slpA protein (SA) from L. acidophilus NCFM was extracted and purified. It had a relative molecular weight of 46 kDa. Circular dichroism measurements suggested that the two S-layer proteins had a high ß-sheet content and a low α-helix structure content. In an adhesion experiment, SA displayed higher adhesive capability towards Caco-2 cells than did SB. The results suggest that these two S-layer proteins could have biotechnological applications.

12.
Can J Microbiol ; 63(3): 228-237, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28177802

RESUMO

The Jerusalem artichoke (JA; Helianthus tuberosus), known to be tolerant to saline-alkaline soil conditions, has been cultivated for many years in the Yellow River delta, Shandong Province coastal zone, in China. The aim of our study was to isolate nitrogen-fixing bacteria colonizing the rhizosphere of JA and to characterize other plant growth promotion properties. The ultimate goal was to identify isolates that could be used as inoculants benefiting an economic crop, in particular for improving wheat growth production in the Yellow River delta. Bacterial strains were isolated from the rhizosphere soil of JA on the basis of growth on nitrogen-free Ashby medium. Identification and phylogenetic analysis was performed after nucleotide sequencing of 16S rRNA gene. Plant-growth-promoting traits, such as nitrogen fixation activity, phosphate solubilization activity, indole-3-acetic acid production, were determined using conventional methods. Eleven strains were isolated and 6 of them were further examined for their level of salt tolerance and their effect on plant growth promotion. Inoculation of Enterobacter sp. strain N10 on JA and wheat led to significant increases in both root and shoot dry mass and shoot height. Enterobacter sp. strain N10 appeared to be the best plant-growth-promoting rhizobacteria to increase wheat productivity in future field applications.


Assuntos
Bactérias/isolamento & purificação , Helianthus/microbiologia , Triticum/crescimento & desenvolvimento , Bactérias/classificação , Bactérias/metabolismo , China , Ácidos Indolacéticos/metabolismo , Nitrogênio , Fixação de Nitrogênio , Filogenia , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Rizosfera , Tolerância ao Sal , Cloreto de Sódio , Microbiologia do Solo , Triticum/genética
13.
Int J Syst Evol Microbiol ; 66(12): 5294-5300, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27653171

RESUMO

A group of Sesbania cannabina rhizobia belonging to four recA genotypes of a novel group was further characterized in comparison with the related Ensifer species. They showed 98.2 to 99.9 % similarities among themselves and 92.9 to 93.3 % similarities with the most related strain Ensifer sojae CCBAU 05684T in multilocus sequence analysis of recA, atpD and glnII. The genome average nucleotide identity values between representative strain YIC4027T and the type strains of its closely related species were 81.6 to 88.9 %. Identical symbiotic gene (nodA, nodC and nifH) sequences highly similar with those in other Sesbania-nodulating strains (Rhizobium sp. SIN-1, Neorhizobium huautlense S02T, Ensifer saheli ORS609T and Rhizobium sp. IRBG74) were detected. The representative strain YIC4027T could form effective nodules on its original host Sesbaniacannabina, but not on Sophora flavescens, Trifolium repens, Glycine max, Glycyrrhiza uralensis, Phaseolus vulgaris or Medicago sativa. The use of lactulose as sole carbon source, possession of C13 : 0 2-OH, C13 : 1 at 12-13, C15 : 1 iso ω9c, C17 : 0 anteiso and C18 : 0 iso and absence of C14 : 0 anteiso, C15 : 0 anteiso and C18 : 0 3-OH in fatty acids distinguished the strain YIC4027T from the type strains of its closely related species. Based on all the analyses mentioned above, we propose a novel species Ensifer alkalisoli sp. nov. and designate YIC4027T (=HAMBI 3655T=LMG 29286T) as the type strain. The genome size of YIC4027T is 5.97 Mbp, comprising 5588 predicted genes, and the DNA G+C content is 62.2 mol%.


Assuntos
Filogenia , Rhizobiaceae/classificação , Nódulos Radiculares de Plantas/microbiologia , Sesbania/microbiologia , Álcalis , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Rhizobiaceae/genética , Rhizobiaceae/isolamento & purificação , Salinidade , Análise de Sequência de DNA , Solo/química , Simbiose
14.
Syst Appl Microbiol ; 39(6): 384-90, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27480059

RESUMO

Beach pea [Lathyrus maritimus Bigelow, or Lathyrus japonicus subsp. maritimus (L.) P.W. Ball] is a wild legume distributed on the seashore line, and the rhizobia nodulating with this plant have been reported only rarely. In order to reveal the diversity of beach pea rhizobia on the seashore line of Shandong Peninsula, China, a total of 124 bacterial strains were isolated from the root nodules of beach pea plants collected from five sites. All the isolates were divided into five recA types after screening by recA gene sequence analysis and they consisted of Rhizobium anhuiense covering 122 symbiotic isolates in three recA types, as well as two single isolates Rhizobium sp. and Rhizobium lusitanum representing distinct recA types. The recA genotype III of R. anhuiense (103 isolates) represented by strain YIC11270 was dominant at all five sampling sites. Identical symbiotic genes (nodC and nifH) were detected in the three recA genotypes of R. anhuiense isolates that were closely related to those of the pea and faba rhizobia. This study clarified that R. anhuiense was the main symbiont for beach pea rhizobia on the seashore line of Shandong Peninsula. The low level genetic diversity of beach pea rhizobia revealed by both MLSA and the symbiotic genes might be related to the strong selection pressure produced by the saline-alkaline environment and the host plants.


Assuntos
Técnicas de Tipagem Bacteriana , Lathyrus/microbiologia , Tipagem de Sequências Multilocus , Rhizobium/classificação , Rhizobium/genética , Nódulos Radiculares de Plantas/microbiologia , Proteínas de Bactérias/genética , Sequência de Bases , China , DNA Bacteriano/genética , Variação Genética/genética , N-Acetilglucosaminiltransferases/genética , Oxirredutases/genética , RNA Ribossômico 16S/genética , Recombinases Rec A/genética , Rhizobium/isolamento & purificação , Análise de Sequência de DNA , Microbiologia do Solo , Simbiose , Fatores de Transcrição/genética
15.
Syst Appl Microbiol ; 39(3): 195-202, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27061259

RESUMO

Sesbania cannabina is a plant that grows naturally along the seashores in Rudong County, China (RDC) and it has been introduced into the Yellow River Delta (YRD) as a pioneer plant to improve the saline-alkaline soils. In order to investigate the diversity of S. cannabina rhizobia in these soils, a total of 198 rhizobial isolates were characterized and phylogenetic trees were constructed based on data from multilocus sequence analysis (MLSA) of the housekeeping genes recA, atpD and glnII, as well as 16S rRNA. Symbiotic features were also studied by establishing the phylogeny of the symbiotic genes nodA and nifH, and by performing nodulation assays. The isolates had highly conserved symbiotic genes and were classified into nine genospecies belonging to the genera Ensifer, Agrobacterium, Neorhizobium and Rhizobium. A unique community structure was detected in the rhizobia associated with S. cannabina in the saline-alkaline soils that was characterized by five novel genospecies and four defined species. In addition, Ensifer sp. I was the predominant rhizobia in YRD, whereas Ensifer meliloti and Neorhizobium huautlense were the dominant species in RDC. Therefore, the study demonstrated for the first time that this plant strongly selected the symbiotic gene background but not the genomic background of its microsymbionts. In addition, biogeographic patterns existed in the rhizobial populations associated with S. cannabina, which were mainly correlated with pH and salinity, as well as the mineral nutrient contents. This study provided novel information concerning the interaction between soil conditions, host plant and rhizobia, in addition to revealing the diversity of S. cannabina rhizobia in saline-alkaline soils.


Assuntos
Agrobacterium/classificação , Agrobacterium/isolamento & purificação , Rhizobium/classificação , Rhizobium/isolamento & purificação , Nódulos Radiculares de Plantas/microbiologia , Sesbania/microbiologia , Aciltransferases/genética , Agrobacterium/genética , Proteínas de Bactérias/genética , China , DNA Bacteriano/genética , Variação Genética/genética , Tipagem de Sequências Multilocus , Oxirredutases/genética , RNA Ribossômico 16S/genética , Recombinases Rec A/genética , Rhizobium/genética , Solo/química , Microbiologia do Solo , Simbiose/genética , Fatores de Transcrição/genética
16.
Wei Sheng Wu Xue Bao ; 55(9): 1105-16, 2015 Sep 04.
Artigo em Chinês | MEDLINE | ID: mdl-26762023

RESUMO

OBJECTIVE: To study the genetic diversity and phylogeny of Rhizobia isolated from Sesbania cannabina growing on the tidal flat in Rudong County and screen high-efficient growth-promoting strains as Rhizobia inoculator to S. cannabina. METHODS: Phylogenetic analyses were based on 16S rRNA gene, housekeeping genes (recA, atpD, glnII) and symbiotic genes (nodA, nifH). The growth-promoting efficiency was tested by plant inoculation assay on S. cannabina in greenhouse. RESULTS: The 32 isolates belonged to Ensifer, Neorhizobium, Rhizobium, and most closely related to E. meliloti, N. huautlense, R. pusense. The phylogenies of nodA and nifH were congruent, and most closely related to E. saheli. The 7 representative isolates were resistant to high concentration of NaCl (5%, W/V), and YIC5082 grew well in TY medium with 6% NaCl. In plant inoculation assay, all the 7 representative isolates were effective on symbiotic nitrogen fixation, and 6 out of the 7 isolates significantly enhanced the fresh weight and height of plants. CONCLUSION: Rhizobia isolated from S. cannabina growing on the tidal flat in Rudong County showed rich genetic diversity. N. huautlense and E. meliloti were the dominant species. Most of the isolates showed fine growth-promoting efficiency and salt tolerance. YIC5077 showed the best growth-promoting efficiency, good nodulation and nitrogen fixation abilities, which has promising potential applications as Rhizobia inoculator to S. cannabina.


Assuntos
Variação Genética , Rhizobiaceae/genética , Rhizobiaceae/isolamento & purificação , Sesbania/crescimento & desenvolvimento , Sesbania/microbiologia , Proteínas de Bactérias/genética , China , DNA Bacteriano/genética , DNA Ribossômico/genética , Dados de Sequência Molecular , Fixação de Nitrogênio , Filogenia , Polimorfismo de Fragmento de Restrição , Rhizobiaceae/classificação , Rhizobiaceae/metabolismo , Cloreto de Sódio/metabolismo
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