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1.
Fa Yi Xue Za Zhi ; 40(1): 64-69, 2024 Feb 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38500463

RESUMO

Biological evidence is relatively common evidence in criminal cases, and it has strong probative power because it carries DNA information for individual identification. At the scene of fire-related cases, the complex thermal environment, the escape of trapped people, the firefighting and rescue operations, and the deliberate destruction of criminal suspects will all affect the biological evidence in the fire scene. Scholars at home and abroad have explored and studied the effectiveness of biological evidence identification in fire scenes, and found that the blood stains, semen stains, bones, etc. are the main biological evidence which can be easily recovered with DNA in fire scenes. In order to analyze the research status and development trend of biological evidence in fire scenes, this paper systematically sorts out the relevant research, mainly including the soot removal technology, appearance method of typical biological evidence, and possibility of identifying other biological evidence. This paper also prospects the next step of research direction, in order to provide reference for the identification of biological evidence and improve the value of biological evidence in fire scenes.


Assuntos
Manchas de Sangue , Líquidos Corporais , Incêndios , Humanos , Sêmen , DNA/genética
2.
Nat Commun ; 14(1): 7356, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37963860

RESUMO

The timely onset of female parturition is a critical determinant for pregnancy success. The highly heterogenous maternal decidua has been increasingly recognized as a vital factor in setting the timing of labor. Despite the cell type specific roles in parturition, the role of the uterine epithelium in the decidua remains poorly understood. This study uncovers the critical role of epithelial SHP2 in parturition initiation via COX1 and COX2 derived PGF2α leveraging epithelial specific Shp2 knockout mice, whose disruption contributes to delayed parturition initiation, dystocia and fetal deaths. Additionally, we also show that there are distinct types of epithelium in the decidua approaching parturition at single cell resolution accompanied with profound epithelium reformation via proliferation. Meanwhile, the epithelium maintains the microenvironment by communicating with stromal cells and macrophages. The epithelial microenvironment is maintained by a close interaction among epithelial, stromal and macrophage cells of uterine stromal cells. In brief, this study provides a previously unappreciated role of the epithelium in parturition preparation and sheds lights on the prevention of preterm birth.


Assuntos
Fenômenos Bioquímicos , Trabalho de Parto , Nascimento Prematuro , Animais , Feminino , Humanos , Recém-Nascido , Camundongos , Gravidez , Parto , Útero
3.
Artigo em Inglês | MEDLINE | ID: mdl-38000290

RESUMO

Natural products provide a new opportunity for the discovery of neuraminidase (NA)inhibitors. In this study, an affinity ultrafiltration (AUF) coupled with HPLC-MS/MS method was firstly developed and optimized for screening of NA inhibitors from natural products. The critical factors influencing the interaction of enzyme-ligand (including sample concentration, enzyme concentration, incubation time and temperature, pH of the buffer, and dissociation solvents and time) were investigated and optimized by a one-factor-at-a-time design. The method was then applied to discover NA inhibitory compounds in stems and leaves of Baphicacanthus cusia. As a result, five active alkaloids were screened out and identifiedas 2,4(1H,3H)-quinazolinedione (1), 4(3H)-quinazolinone (2), 2(3H)-benzoxazolone (3), tryptanthrin (4), and indirubin (5) through analysis of their DAD profiles, MS/MS fragments, and comparison with reference substances. These active compounds were further evaluated for their NA inhibitory activity using a fluorescence-based NA inhibition assay. The result from the fluorescent assay revealed that all the five compounds(1-5) showed pronounced NA inhibitory activities with IC50values of 98.98, 64.69, 40.16, 69.44, and 144.73 µM, respectively. Finally, molecular docking of these five alkaloids with NA showed that hydrogen bond and π-cation interactions dominated within the binding sites with binding energies ranging between -5.7 to -7.9 kcal/mol, which was supported by the results of the AUF and the fluorescence-based enzyme assay. The developed AUF method is simple and efficient for screening potential NA inhibitors from stems and leaves of B. cusia.


Assuntos
Alcaloides , Espectrometria de Massas em Tandem , Simulação de Acoplamento Molecular , Neuraminidase , Ultrafiltração/métodos , Inibidores Enzimáticos/análise , Extratos Vegetais/química , Corantes
4.
J Phys Condens Matter ; 35(26)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36990098

RESUMO

The amorphous selenium (a-Se) was studied via x-ray diffraction (XRD) under pressures ranging from ambient pressure up to 30 GPa at room temperature to study its high-pressure behavior. Two compressional experiments on a-Se samples, with and without heat treatment, respectively, were conducted. Contrary to the previous reports that a-Se crystallized abruptly at around 12 GPa, in this work we report an early partially crystallized state at 4.9 GPa before completing the crystallization at around 9.5 GPa based onin-situhigh pressure XRD measurements on the a-Se with 70 °C heat treatment. In comparison, crystallization pressure on another a-Se sample without thermal treatment history was observed to be 12.7 GPa, consistent with the previously reported crystallization pressure. Thus, it is proposed in this work that prior heat treatment of a-Se can result in an earlier crystallization under high pressure, which helps to understand the possible mechanism caused by the previous controversial reports on pressure induced crystallization behavior in a-Se.

5.
Int J Biol Macromol ; 229: 909-930, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36608864

RESUMO

The genus Polygonatum is gaining increasing attention from nutrition experts as well as health-conscious consumers because of its excellent performance in providing nutrients. Among these plants, Polygonatum sibiricum and Polygonatum odoratum have been selected for inclusion in China's Medicinal Food Directory due to their high safety profile. Polysaccharides are considered the main functional component and one of the main active ingredients of the plant. In addition, polysaccharides from genus Polygonatum have a variety of nutritional, biological and health-promoting properties, such as immunomodulatory, anti-inflammatory, cardiovascular protective, neuroprotective, antitumor, antidiabetic, antiosteoporosis, and hepatoprotective properties. This paper reviews the origin, extraction, purification, structural characteristics, biological activity, safety, toxicological evaluation, and structure-activity relationship of polysaccharides from the genus Polygonatum. Ultimately, we hope that this work can provide a more useful reference for understanding the polysaccharide structure and developing of new functional foods from polysaccharides of the genus Polygonatum.


Assuntos
Polygonatum , Polygonatum/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Antioxidantes/química , Imunomodulação , Hipoglicemiantes
6.
PLoS Genet ; 18(1): e1010018, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35025868

RESUMO

Approximately 75% of failed pregnancies are considered to be due to embryo implantation failure or defects. Nevertheless, the explicit signaling mechanisms governing this process have not yet been elucidated. Here, we found that conditional deletion of the Shp2 gene in mouse uterine stromal cells deferred embryo implantation and inhibited the decidualization of stromal cells, which led to embryonic developmental delay and to the death of numerous embryos mid-gestation, ultimately reducing female fertility. The absence of Shp2 in stromal cells increased the proliferation of endometrial epithelial cells, thereby disturbing endometrial epithelial remodeling. However, Shp2 deletion impaired the proliferation and polyploidization of stromal cells, which are distinct characteristics of decidualization. In human endometrial stromal cells (hESCs), Shp2 expression gradually increased during the decidualization process. Knockout of Shp2 blocked the decidual differentiation of hESCs, while Shp2 overexpression had the opposite effect. Shp2 knockout inhibited the proliferation of hESCs during decidualization. Whole gene expression profiling analysis of hESCs during the decidualization process showed that Shp2 deficiency disrupted many signaling transduction pathways and gene expression. Analyses of hESCs and mouse uterine tissues confirmed that the signaling pathways extracellular regulated protein kinases (ERK), protein kinase B (AKT), signal transducer and activator of transcription 3 (STAT3) and their downstream transcription factors CCAAT/enhancer binding protein ß (C/EBPß) and Forkhead box transcription factor O1 (FOXO-1) were involved in the Shp2 regulation of decidualization. In summary, these results demonstrate that Shp2 plays a crucial role in stromal decidualization by mediating and coordinating multiple signaling pathways in uterine stromal cells. Our discovery possibly provides a novel key regulator of embryo implantation and novel therapeutic target for pregnancy failure.


Assuntos
Decídua/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Útero/citologia , Animais , Linhagem Celular , Proliferação de Células , Implantação do Embrião , Feminino , Deleção de Genes , Perfilação da Expressão Gênica , Humanos , Camundongos , Gravidez , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Transdução de Sinais , Células Estromais/citologia , Células Estromais/metabolismo , Útero/metabolismo
7.
Blood Adv ; 4(18): 4538-4549, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32956453

RESUMO

B-cell maturation antigen (BCMA), a member of the tumor necrosis factor family of receptors, is predominantly expressed on the surface of terminally differentiated B cells. BCMA is highly expressed on plasmablasts and plasma cells from multiple myeloma (MM) patient samples. We developed a BCMAxCD3 bispecific antibody (teclistamab [JNJ-64007957]) to recruit and activate T cells to kill BCMA-expressing MM cells. Teclistamab induced cytotoxicity of BCMA+ MM cell lines in vitro (H929 cells, 50% effective concentration [EC50] = 0.15 nM; MM.1R cells, EC50 = 0.06 nM; RPMI 8226 cells, EC50 = 0.45 nM) with concomitant T-cell activation (H929 cells, EC50 = 0.21 nM; MM.1R cells, EC50 = 0.1 nM; RPMI 8226 cells, EC50 = 0.28 nM) and cytokine release. This activity was further increased in the presence of a γ-secretase inhibitor (LY-411575). Teclistamab also depleted BCMA+ cells in bone marrow samples from MM patients in an ex vivo assay with an average EC50 value of 1.7 nM. Under more physiological conditions using healthy human whole blood, teclistamab mediated dose-dependent lysis of H929 cells and activation of T cells. Antitumor activity of teclistamab was also observed in 2 BCMA+ MM murine xenograft models inoculated with human T cells (tumor inhibition with H929 model and tumor regression with the RPMI 8226 model) compared with vehicle and antibody controls. The specific and potent activity of teclistamab against BCMA-expressing cells from MM cell lines, patient samples, and MM xenograft models warrant further evaluation of this bispecific antibody for the treatment of MM. Phase 1 clinical trials (monotherapy, #NCT03145181; combination therapy, #NCT04108195) are ongoing for patients with relapsed/refractory MM.


Assuntos
Anticorpos Biespecíficos , Mieloma Múltiplo , Animais , Anticorpos Biespecíficos/farmacologia , Antígeno de Maturação de Linfócitos B , Humanos , Ativação Linfocitária , Camundongos , Mieloma Múltiplo/tratamento farmacológico , Linfócitos T
8.
Front Microbiol ; 11: 1411, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32793125

RESUMO

The use of plant allelopathy to control weeds in the field has been generally recognized as a win-win strategy because it is an environmentally friendly and resource-saving method. The mechanism of this natural weed-control method relies on allelochemicals, the rhizosphere microbiome, and their bio-interaction, and exploring the link between allelochemicals and specific microbes helps accelerate the application of allelopathic characteristics in farming. In this study, we used allelopathic rice PI312777 (PI), its genetically modified OsPAL2-1 repression (PR) or overexpression (PO) lines, and non-allelopathic rice Lemont (Le) as donor plants to reveal the bio-interaction between rice allelochemicals and rhizosphere specific microorganisms. The results showed a higher content of phenolic acid exudation from the roots of PI than those of Le, which resulted in a significantly increased population of Myxococcus in the rhizosphere soil. Transgenic PO lines exhibited increasing exudation of phenolic acid, which led to the population of Myxococcus xanthus in the rhizosphere soil of PO to be significantly increased, while PR showed the opposite result in comparison with wild type PI. Exogenous application of phenolic acid induced the growth of M. xanthus, and the expressions of chemotaxis-related genes were up-regulated in M. xanthus. In addition, quercetin was identified in the culture medium; according to the bioassay determination, a quercetin concentration of 0.53 mM inhibited the root length by 60.59%. Our study indicates that OsPAL2-1 is among the efficient genes that regulate rice allelopathy by controlling the synthesis of phenolic acid allelochemicals, and phenolic acid (ferulic acid, FA) induces the chemotactic aggregation of M. xanthus, which promoted the proliferation and aggregation of this microbe. The potential allelochemical, quercetin was generated from the FA-induced M. xanthus cultured medium.

9.
BMC Plant Biol ; 20(1): 265, 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32517652

RESUMO

BACKGROUND: Identification of the allelopathy-interrelated metabolites from the allelopathic rice rhizosphere is crucial to understand the allelopathic mechanism of rice, which in turn can promote its applications to farming. In this study, the metabolites from the rhizosphere soil of five different rice lines, including allelopathic rice accession PI312777 (PI) and non-allelopathic rice accession Lemont (Le) as well as their genetic derivatives (e.g., phenylalanine ammonia-lyase (PAL) gene overexpression transgenic lines of PI and Le, namely, PO and LO respectively, and PAL RNA interference line of PI, namely, PR) were identified and comparatively analyzed to explore the positive compounds that are involved in the process of rice allelopathy. RESULTS: The results showed that 21 non-polar compounds and 21 polar compounds differed in content in the rhizosphere soil of PI and Le, which include several volatile fatty acids and long-chain fatty acids. The relative contents of fatty acids also differed between PAL overexpressing or RNA interference (RNAi)-silenced line and their wild-type respectively. Acetic acid content also differed among groups, i.e., it is higher in the high allelopathic potential rice. Further analysis showed that different metabolites from the ADS8 resin-extracted phase were more abundant than that those from the ADS21 resin-extracted phase, suggesting that the allelochemicals in root exudates of allelopathic rice are mainly non-polar substances. KEGG annotation of these differential metabolites revealed that these compounds were related to nutrient metabolism, secondary metabolite synthesis, signaling substance synthesis, and toxin degradation. CONCLUSIONS: Rice allelochemicals deposited in the ADS8 resin-extracted phase were more abundant than those in the ADS21 resin-extracted phase. Allelochemicals in root exudates of allelopathic rice are mainly non-polar substances, and long-chain fatty acids are considered as allelopathy interrelated metabolites.


Assuntos
Alelopatia , Oryza/metabolismo , Rizosfera , Alelopatia/genética , Produção Agrícola , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Oryza/genética , Plantas Geneticamente Modificadas , Solo/química
10.
Blood Cancer J ; 10(6): 65, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483120

RESUMO

Redirecting T cells to specifically kill malignant cells has been validated as an effective anti-cancer strategy in the clinic with the approval of blinatumomab for acute lymphoblastic leukemia. However, the immunosuppressive nature of the tumor microenvironment potentially poses a significant hurdle to T cell therapies. In hematological malignancies, the bone marrow (BM) niche is protective to leukemic stem cells and has minimized the efficacy of several anti-cancer drugs. In this study, we investigated the impact of the BM microenvironment on T cell redirection. Using bispecific antibodies targeting specific tumor antigens (CD123 and BCMA) and CD3, we observed that co-culture of acute myeloid leukemia or multiple myeloma cells with BM stromal cells protected tumor cells from bispecific antibody-T cell-mediated lysis in vitro and in vivo. Impaired CD3 redirection cytotoxicity was correlated with reduced T cell effector responses and cell-cell contact with stromal cells was implicated in reducing T cell activation and conferring protection of cancer cells. Finally, blocking the VLA4 adhesion pathway in combination with CD3 redirection reduced the stromal-mediated inhibition of cytotoxicity and T cell activation. Our results lend support to inhibiting VLA4 interactions along with administering CD3 redirection therapeutics as a novel combinatorial regimen for robust anti-cancer responses.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Medula Óssea/efeitos dos fármacos , Complexo CD3/imunologia , Integrina alfa4beta1/antagonistas & inibidores , Leucemia Mieloide Aguda/tratamento farmacológico , Mieloma Múltiplo/tratamento farmacológico , Animais , Anticorpos Biespecíficos/farmacologia , Anticorpos Biespecíficos/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Antígeno de Maturação de Linfócitos B/antagonistas & inibidores , Antígeno de Maturação de Linfócitos B/imunologia , Medula Óssea/imunologia , Medula Óssea/patologia , Complexo CD3/antagonistas & inibidores , Linhagem Celular Tumoral , Feminino , Humanos , Integrina alfa4beta1/imunologia , Subunidade alfa de Receptor de Interleucina-3/antagonistas & inibidores , Subunidade alfa de Receptor de Interleucina-3/imunologia , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/patologia , Camundongos , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/patologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/patologia , Microambiente Tumoral/efeitos dos fármacos
11.
J Hazard Mater ; 395: 122665, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32315795

RESUMO

The existence of heavy metals in wastewater has obtained more attention due to its high toxicity and non-degradability. In this study, we investigated the changes of anaerobic ammonium oxidation (Anammox) system under long-term invasion of Hg(Ⅱ). The results indicated that the total nitrogen removal efficiency (TNRE) dropped to around 55 % as Hg(Ⅱ) concentration went up to 20 mg L-1. But the functional bacteria rapidly developed some resistant abilities and maintained a stable TNRE of 65 % till the end of test. The maximum relative expression fold change of merA, merB, merD and merR were 468.8476, 23.7383, 5.0321 and 15.2514 times, respectively. The high positive correlation between the expression abundance of metal resistance genes and the concentrations of Hg(Ⅱ) revealed the resistant mechanisms of microorganisms to heavy metals. Moreover, the protective strategy based on extracellular polymeric substances also contributed to the stability of Anammox system.


Assuntos
Compostos de Amônio , Mercúrio , Microbiota , Anaerobiose , Biofilmes , Reatores Biológicos , Desnitrificação , Mercúrio/toxicidade , Nitrogênio/análise , Oxirredução , Esgotos
12.
Blood ; 135(15): 1232-1243, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32040549

RESUMO

T-cell-mediated approaches have shown promise in myeloma treatment. However, there are currently a limited number of specific myeloma antigens that can be targeted, and multiple myeloma (MM) remains an incurable disease. G-protein-coupled receptor class 5 member D (GPRC5D) is expressed in MM and smoldering MM patient plasma cells. Here, we demonstrate that GPRC5D protein is present on the surface of MM cells and describe JNJ-64407564, a GPRC5DxCD3 bispecific antibody that recruits CD3+ T cells to GPRC5D+ MM cells and induces killing of GPRC5D+ cells. In vitro, JNJ-64407564 induced specific cytotoxicity of GPRC5D+ cells with concomitant T-cell activation and also killed plasma cells in MM patient samples ex vivo. JNJ-64407564 can recruit T cells and induce tumor regression in GPRC5D+ MM murine models, which coincide with T-cell infiltration at the tumor site. This antibody is also able to induce cytotoxicity of patient primary MM cells from bone marrow, which is the natural site of this disease. GPRC5D is a promising surface antigen for MM immunotherapy, and JNJ-64407564 is currently being evaluated in a phase 1 clinical trial in patients with relapsed or refractory MM (NCT03399799).


Assuntos
Anticorpos Biespecíficos/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Mieloma Múltiplo/terapia , Receptores Acoplados a Proteínas G/imunologia , Linfócitos T/efeitos dos fármacos , Animais , Anticorpos Biespecíficos/imunologia , Antineoplásicos Imunológicos/imunologia , Linhagem Celular Tumoral , Citotoxicidade Imunológica/efeitos dos fármacos , Feminino , Humanos , Imunoterapia , Camundongos Endogâmicos BALB C , Mieloma Múltiplo/imunologia , Linfócitos T/imunologia
13.
RSC Adv ; 10(65): 39712-39721, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-35515382

RESUMO

In this investigation, aramid pulp (AP) was introduced into acrylonitrile-butadiene rubber (NBR)-based composites in various amounts by two different introduction methods. An AP/NBR predispersion was applied to improve the AP dispersion in the matrix, and its effects on the characteristics and properties of the composites were studied. The results showed that the optimum curing time of the compounds was affected by the AP introduction method due to heat generation at different mixing stages. The addition of AP affected the swelling properties and significantly improved the hardness, modulus and tear strength. The tensile strength decreased and then increased with increasing AP content. The AP predispersion obviously further improved the tensile strength of the composites with AP content above 7.5 phr owing to better fiber network formation inside the rubber matrix during the stretching process. The dynamic mechanical properties were not sensitive to the AP introduction method. The addition of AP was conducive to the wear resistance, and the dispersion improvement could further enhance the uniformity of the worn surface and mitigate crack generation.

14.
J Exp Bot ; 71(6): 2127-2141, 2020 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-31811717

RESUMO

Rice allelopathy is a natural method of weed control that is regarded as an eco-friendly practice in agroecology. The allelopathic potential of rice is regulated by various genes, including those that encode transcription factors. Our study characterized a MYB transcription factor, OsMYB57, to explore its role in the regulation of rice allelopathy. Increasing the expression of OsMYB57 in rice using the transcription activator VP64 resulted in increased inhibitory ratios against barnyardgrass. The gene expression levels of OsPAL, OsC4H, OsOMT, and OsCAD from the phenylpropanoid pathway were also up-regulated, and the content of l-phenylalanine increased. Chromatin immunoprecipitation incorporated with HiSeq demonstrated that OsMYB57 transcriptionally regulated a mitogen-activated protein kinase (OsMAPK11); in addition, OsMAPK11 interacted with OsPAL2;3. The expression of OsPAL2;3was higher in the allelopathic rice PI312777 than in the non-allelopathic rice Lemont, and OsPAL2;3 was negatively regulated by Whirly transcription factors. Moreover, microbes with weed-suppression potential, including Penicillium spp. and Bacillus spp., were assembled in the rhizosphere of the rice accession Kitaake with increased expression of OsMYB57, and were responsible for phenolic acid induction. Our findings suggest that OsMYB57 positively regulates rice allelopathy, providing an option for the improvement of rice allelopathic traits through genetic modification.


Assuntos
Echinochloa , Oryza , Alelopatia , Oryza/genética , Rizosfera
15.
RSC Adv ; 9(60): 34744-34753, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-35530704

RESUMO

In this study, the effects of water ageing on characteristics and properties of basalt fibre (BF)/acrylonitrile-butadiene rubber (NBR) composites were investigated, and the tribological behaviours of the composites that slide against the stainless-steel counterpart under water lubrication at 30-70 °C were the main focus. Results showed that with the water temperature increase, the hardness and tear strength of the water-aged samples decreased. Furthermore, both the friction coefficient (COF) and specific wear rate (W s) of the composites increased with the temperature. The content and the orientation of BFs had no obvious effect on the COF, whereas the parallel-aligned BFs were effective at improving the wear resistance of the composites at both 30 °C and 70 °C.

16.
J Hazard Mater ; 367: 182-187, 2019 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-30594718

RESUMO

Long-term impacts of two antibiotics-norfloxacin (NOR) and erythromycin (ERY) in trace concentration (1ug L-1) on Anammox biofilm were investigated. The specific Anammox activity (SAA) and dehydrogenase activity (DHA) of Anammox biofilm were detected by batch experiments, the microbial diversity was analyzed using high-throughput sequencing technology and the antibiotic resistance genes (ARGs) were measured by qPCR. Results showed that long-term NOR feeding decreased 30% SAA and 39.6% DHA, and also decreased the abundance of the OTUs related to autotrophic nitrogen removal, while ERY had slight impact on Anammox. Only two ARGs targeted to ERY (ermB, mphA) were detected in the two Anammox systems while those targeted to NOR (qnrA, qnrB, qnrD, and qnrS) were not detected. The relative expression of ermB to 16S rRNA increased from 2.08±0.32×10-4 to 3.53±1.18×10-4, and that of mphA increased to 5.00±0.48×10-4 from 4.48±1.32×10-5. The induced ARGs in the Anammox system help it resist the ERY shock.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Reatores Biológicos , Resistência Microbiana a Medicamentos/genética , Eritromicina/farmacologia , Norfloxacino/farmacologia , Poluentes Químicos da Água/farmacologia , Proteínas de Bactérias/metabolismo , Genes Bacterianos , Oxirredutases/metabolismo , RNA Ribossômico 16S , Eliminação de Resíduos Líquidos , Águas Residuárias
17.
Plant Sci ; 262: 115-126, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28716407

RESUMO

Frequent cold spells in late spring can damage early rice seedlings. However, overexpression of the silicon-uptake gene Lsi1 (Lsi1-OX) in cold-sensitive rice (Oryza sativa L., accession: Dular) notably enhances its chilling resistance. In this study, we found that continual chilling led to chlorophyll and RNA degradation in wild-type Dular leaves, whereas leaves from a Lsi1-OX line exhibited no obvious changes. A comparison of the global mRNA expression between the two rice lines showed that genes encoding photosynthesis-antenna proteins were downregulated and those encoding the proteasome were upregulated in the wild-type organism. Moreover, the differential responses of the two rice lines to chilling stress were found to correlate with the transcription factor OsWRKY53, which was predicted target of the respective microRNA (miRNA) novel-m0586-5p. In addition, miRNAs that targeted genes involved in the process of reactive oxygen species (ROS) metabolism were differentially expressed in the two rice lines after chilling stress, when comparative analysis of the outcomes of RNA sequencing on the two rice lines. Our results suggest that when overexpressed Lsi1 in cold-sensitive rice, it possibility regulates the transcription factor OsWRKY53 in addition to the genes involved in the ROS metabolism, thus mediating resistance to chilling stress.


Assuntos
Oryza/metabolismo , Oryza/fisiologia , Proteínas de Plantas/metabolismo , Temperatura Baixa , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Oryza/genética , Fotossíntese/genética , Fotossíntese/fisiologia , Proteínas de Plantas/genética , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
18.
Sci Rep ; 6: 34569, 2016 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-27694845

RESUMO

UVB radiation causes cyclobutane pyrimidine dimers (CPDs) to form on the DNA of living organisms. This study found that overexpression of the silicon absorbance gene Lsi1 reduced the accumulation of CPDs in rice, which profited from the reactivation by photolyase. The transcript abundance of deoxyribodipyrimidine photolyase (Os10g0167600) was generally correlated with the silicon content of the rice, and the up-regulation of Os10g0167600 was found to be highest in the UVB-treated Lsi1-overexpressed (Lsi1-OX) rice. A trans-acting factor, methyl-CpG binding domain protein (OsMeCP), was found to interact with the cis-element of Os10g0167600. The nucleic location of OsMeCP effectively enabled the transcriptional regulation. Compared with the WT, the level of OsMeCP was lower in the Lsi1-OX rice but higher in the Lsi1-RNAi line. Rice cultured in a high silicate-concentration solution also exhibited less OsMeCP abundance. Overexpression of OsMeCP led to lower Os10g0167600 transcript levels and a higher CPD content than in the WT, but the reverse was true in the OsMeCP-RNAi line. These findings indicate that OsMeCP acts as a negative regulator of silicon, and can mediate the repression of the transcription from Os10g0167600, which inhibits the photoreactivation of the photolyase involved in the repair of CPDs.


Assuntos
Reparo do DNA , DNA de Plantas , Proteínas de Ligação a DNA , Oryza , Proteínas de Plantas , Dímeros de Pirimidina , Raios Ultravioleta , DNA de Plantas/genética , DNA de Plantas/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Desoxirribodipirimidina Fotoliase/genética , Desoxirribodipirimidina Fotoliase/metabolismo , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Dímeros de Pirimidina/genética , Dímeros de Pirimidina/metabolismo
19.
Plant Cell Environ ; 38(7): 1368-81, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25438645

RESUMO

Rice allelopathy is a hot topic in the field of allelopathy, and behaviour of donor allelopathic rice has been well documented. However, few study addresses response of receiver barnyardgrass (BYG). We found that expression of miRNAs relevant to plant hormone signal transduction, nucleotide excision repair and the peroxisome proliferator-activated receptor and p53 signalling pathways was enhanced in BYG co-cultured with the allelopathic rice cultivar PI312777, the expression levels of these miRNAs in BYG plants were positively correlated with allelopathic potential of the co-cultured rice varieties. Treatment of BYG plants with rice-produced phenolic acids also increased miRNA expression in BYG, while treatment with rice-produced terpenoids had no obvious effect on miRNA expression. In the hydroponic system, the largest number of Myxococcus sp. was found in the growth medium containing rice with the highest allelopathic potential. The addition of phenolic acids in the hydroponic medium also increased the number of Myxococcus sp. More interestingly, inoculation with Myxococcus xanthus significantly increased miRNA expression in the treated BYG. Jointed treatments of ferulic acid and M. xanthus led to strongest growth inhibition of BYG. The results suggest that there exist involvement of Myxococcus sp. and mediation of miRNA expression in rice allelopathy against BYG.


Assuntos
Alelopatia , Echinochloa/genética , MicroRNAs/genética , Myxococcus xanthus/fisiologia , Oryza/química , Ácidos Cumáricos/farmacologia , Echinochloa/efeitos dos fármacos , Echinochloa/crescimento & desenvolvimento , Echinochloa/fisiologia , Hidroponia , Hidroxibenzoatos/farmacologia , Ácidos Indolacéticos/metabolismo , MicroRNAs/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/fisiologia , Plantas Geneticamente Modificadas , Análise de Sequência de RNA , Transdução de Sinais , Terpenos/farmacologia
20.
J Chem Ecol ; 39(2): 204-12, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23385369

RESUMO

Gene expression of phenylalanine ammonia-lyase (PAL) in allelopathic rice PI312777 was inhibited by RNA interference (RNAi). Transgenic rice showed lower levels of PAL gene expression and PAL activity than wild type rice (WT). The concentrations of phenolic compounds were lower in the root tissues and root exudates of transgenic rice than in those of wild type plants. When barndyardgrass (BYG) was used as the receiver plant, the allelopathic potential of transgenic rice was reduced. The sizes of the bacterial and fungal populations in rice rhizospheric soil at the 3-, 5-, and 7-leaf stages were estimated by using quantitative PCR (qPCR), which showed a decrease in both populations at all stages of leaf development analyzed. However, PI312777 had a larger microbial population than transgenic rice. In addition, in T-RFLP studies, 14 different groups of bacteria were detected in WT and only 6 were detected in transgenic rice. This indicates that there was less rhizospheric bacterial diversity associated with transgenic rice than with WT. These findings collectively suggest that PAL functions as a positive regulator of rice allelopathic potential.


Assuntos
Oryza/genética , Oryza/metabolismo , Fenilalanina Amônia-Liase/genética , Feromônios/metabolismo , Raízes de Plantas/metabolismo , Interferência de RNA , Echinochloa/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Fenóis/metabolismo , Raízes de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Rizosfera , Controle de Plantas Daninhas
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