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1.
J Nanosci Nanotechnol ; 20(5): 3105-3116, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31635654

RESUMO

The Z-scheme Bi2WO6/NaBiO3 nanocomposites were first fabricated by a facile hydrothermal method, and were then characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, energy dispersive spectrometer, Fourier-transform-infrared spectroscopy, X-ray photoelectron spectroscopy and N2 adsorption-desorption. The as-prepared Bi2WO6/NaBiO3 nanocomposites exhibit outstanding photocatalytic activity and recyclability. A 98.4% photodegradation of 2,3-dichlorophenol (50 mg·L-1) was attained in the presence of Bi2WO6/NaBiO3 (1:10) under the visible-light irradiation in 30 min. In particular, the photocatalytic mechanism has been discussed in detail, based on four aspects: (1) oxidative species, (2) photoelectrochemical performance, (3) conduction band and valence band energy levels and (4) possible transition states and reactions. In conclusion, O-2 is the main active oxidative species in the Bi2WO6/NaBiO3 nanocomposite. The material has higher photocurrent and visible light adsorption but lower electron-hole pairs recombination, which contributes to distinguished photocatalytic efficiency. The Z-scheme photocatalytic path was proposed and the possible degradation process and routes have been summarized.

2.
Histol Histopathol ; : 18186, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31745968

RESUMO

Gallbladder cancer (GBC) is a malignant tumor of the biliary tract. The main problem affecting the treatment of gallbladder cancer is late diagnosis and poor prognosis. EIF5A2 is one of two isoforms of the EIF5A family and is reported to be a new oncogenic protein in many human cancers. In this study, our results showed for the first time that EIF5A2 was overexpressed in GBC samples compared with non-tumor tissue. Overexpression of EIF5A2 was associated with lymph node metastasis, tumor differentiation, UICC (Union for International Cancer Control) staging, histological type, metastasis, and tumor size. Overexpression of EIF5A2 in gallbladder carcinoma tissues is also associated with poor prognosis in patients. The interference of EIF5A2 significantly inhibited the proliferation, cell cycle, migration and colony formation of GBC-SD cells in vitro. Our results suggest that EIF5A2 is a target oncogene and may be an important prognostic biomarker in the pathogenesis of gallbladder cancer.

3.
Molecules ; 24(9)2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31086098

RESUMO

Natural daphnane diterpenoids, mainly distributed in plants of the Thymelaeaceae and Euphorbiaceae families, usually include a 5/7/6-tricyclic ring system with poly-hydroxyl groups located at C-3, C-4, C-5, C-9, C-13, C-14, or C-20, while some special types have a characteristic orthoester motif triaxially connectedat C-9, C-13, and C-14. The daphnane-type diterpenoids can be classified into five types: 6-epoxy daphnane diterpenoids, resiniferonoids, genkwanines, 1-alkyldaphnanes and rediocides, based on the oxygen-containing functions at rings B and C, as well as the substitution pattern of ring A. Up to now, nearly 200 daphnane-type diterpenoids have been isolated and elucidated from the Thymelaeaceae and Euphorbiaceae families. In-vitro and in-vivo experiments of these compounds have shown that they possess a wide range of biological activities, including anti-HIV, anti-cancer, anti-leukemic, neurotrophic, pesticidal and cytotoxic effects. A comprehensive account of the structural diversity is given in this review, along with the cytotoxic activities of daphnane-type diterpenoids, up to April 2019.


Assuntos
Diterpenos/química , Euphorbiaceae/química , Thymelaeaceae/química , Animais , Fármacos Anti-HIV/química , Antineoplásicos/química , Humanos , Estrutura Molecular
4.
New Phytol ; 223(3): 1388-1406, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31050354

RESUMO

The translation initiation factor eIF4E-binding protein-mediated regulation of protein translation by interfering with assembly of mRNA cap-binding complex eIF4F is well described in mammalian and yeast cells. However, it remains unknown whether a signaling regulator or pathway interacts directly with any translation initiation factor to modulate assembly of eIF4F in plant cells. Here, we report that the two isoforms of Arabidopsis eIF4G, eIFiso4G1 and eIFiso4G2, interact with a cytoplasmic-nuclear dual-localized pentatricopeptide repeat protein SOAR1 to regulate abscisic acid (ABA) signaling. SOAR1 inhibits interactions of eIFiso4E, eIF4Es, eIF4A1, eIF4B2 and poly(A)-binding protein PAB6 with eIFiso4G1 and eIFiso4G2, thereby inhibiting eIFiso4F/mixed eIF4F assembly and repressing translation initiation. SOAR1 binds mRNA of a key ABA-responsive gene ABI5 and cooperates with eIFiso4G1/2 to repress translation of ABI5. The binding of SOAR1 to ABI5 mRNA is likely to inhibit the interaction of SOAR1 with eIFiso4G1/2, suggesting a regulatory loop. Our findings identify a novel translation initiation repressor interfering with cap-binding complex assembly, and establish a link between cap-binding complex assembly and ABA signaling.

5.
Zootaxa ; 4544(4): 598-600, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30647262

RESUMO

The genus Haplotropis Saussure, 1888 belongs to family Pamphagidae, superfamily Acridioidea. It contains three species: Haplotropis brunneriana Saussure, 1888; Haplotropis xiai Ye, Shi Li 2016 and Haplotropis zhuoluensis Ye, Shi Li 2016 distributed mainly in Amur River region of Asia and China only (Saussure, 1888; Bey-Bienko et Mishchenko, 1951; Otte, 1994; Yin, Shi et Yin, 1996; Storozhenko Paik, 2011; Yin et al, 2014, Dong et al, 2015; Ye et al, 2016; Zhang et al, 2017; Cigliano et al, 2018). A new species Haplotropis aqiensis sp. nov. is described in this paper. The new species is similar to H. xiai Ye et al., 2016, but differs from latter by tegmina of male extending over the hind margin of first abdominal tergite slightly, length of tegmina 1.7 times width, cover 2/3 tympanum; frontal ridge of male not widened at median ocellus; length interspace of mesosternum in male equal narrowest width; apical half part of cercus suddenly tapering in male and lower margin of epiphallus without projection in the middle. Type specimen is deposited in the College of Plant Protection, Shandong Agricultural University, Taian, Shandong, China.


Assuntos
Ortópteros , Distribuição Animal , Estruturas Animais , Animais , Ásia , Tamanho Corporal , China , Masculino , Tamanho do Órgão
6.
Infect Dis Poverty ; 7(1): 123, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30509315

RESUMO

BACKGROUND: In an era when HIV transmission has been on the rise among men who have sex with men (MSM), transgender women may play a considerable role in China's current HIV epidemic as a potential "bridge" of HIV transmission between homosexual and heterosexual populations. We sought to understand the risk behaviours and factors associated with HIV infection among transgender women in two cities in China. METHODS: From January to December 2016, we recruited transgender women with the help of community-based organizations (CBOs) through a wide range of methods, including snowball sampling. After recruitment, we asked participants to fill out a structured questionnaire including questions about socio-demographics, sexual behaviours, condom use, substance use and uptake of health care services. HIV infection status was determined by using two different rapid testing reagents. RESULTS: Among 498 subjects enrolled in this study, 233 were from Shanghai and 265 were from Tianjin. The median age was 30 years (range: 18-68; IQR: 24-33). Of them, 337 (67.7%) preferred feminine dress, 13 (2.6%) had undergone transsexual operation and 68 (13.7%) had used hormones for transition purposes. Nearly half (45.6%) reported having regular partners, and 351 (70.5%) had casual partners. Regarding condom use, 81.5% reported not always using condoms with stable partners, and 70.9% reported not using condoms with casual partners. Twenty-five (5.0%) had a history of buying sex and fifty-one (10.2%) had a history of selling sex in the past three months. A total of 200 (40.2%) participants had used at least one kind of controlled substance in the past six months. The most commonly used substances were amyl nitrates (rush popper) (99.5%) and 5-MeO-DiPT (20.0%). Among rush popper users, 170 (85.4%) reported always having sex while on the drug, and 177 (88.9%) reported increased sexual pleasure after using the drug. The HIV infection risk factors identified in our study were being located in Shanghai (aOR = 9.35, 95% CI = 3.89-22.49), selling sex in the past three months (aOR = 3.44, 95% CI = 1.31-9.01), and substance use in the past six months (aOR = 5.71, 95% CI = 2.63-12.41). CONCLUSIONS: Transgender women bear a high HIV burden in the two Chinese cities. Those involved in commercial sex tended to have inconsistent condom use, leading to high risk of HIV infection. Substance use was an independent risk factor of HIV infection by increasing sexual activities and unprotected sex, which indicated an aggravated and complex situation with possible interacting syndemic factors that could cumulatively facilitate sexual risk behaviours and HIV infection in transgender women. There is an urgent need for innovative and appropriate HIV prevention programmes targeting this unique population. Efforts should be made to provide them with tailored services including persuasive communication on consistent condom use, substance use counselling and related referral services, all with the goal of reducing HIV epidemic among transgender women.

7.
Zootaxa ; 4455(3): 593-596, 2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-30314207

RESUMO

The genus Xya Latreille, 1808 obtains 56 known species in the world, among them 20 species distributed in Asia and 7 species in China only i.e. Xya japonica (Haan, 1842); Xya nitobei (Shiraki, 1911); Xya manchurei Shiraki, 1936; Xya apicicornis (Chopard, 1928); Xya riparia (Saussure, 1877); Xya leshanensis Cao et al, 2017 and Xya sichuanensis Cao et al, 2018, [Haan, 1844; Walker, 1871; Saussure, 1877, 1896; Brunner von Wattenwyl. 1893; Bolivar, 1900(1899); Shiraki, 1911, 1936; Chopard, 1928, 1936, 1968; Bey-Bienko, 1967; Günther, 1974. 1980; Ingrisch, 1987; Yin et al, 1996; Murai, 2005; Yin et al, 2013; Heads Hollier, 2016; Kuravova Kocarek, 2016; Zhang et al, 2017; Cao et al, 2017; Cao et al, 2018; Cigliano et al, 2018]. In the present paper, we describe a new species of the genus from Junan county, Shandong province, China. The new species Xya shandongensis sp. nov. is similar to Xya japonica (Haan, 1842), but differs from latter by antennae near moniliform, length of segment 1.2 times maximum width, median and lateral ocelli placed median part of eyes, pronotum with larger yellow stripe on hind apical part of both sides, hind femur black, upper side with a yellowish-white spot at the base of 1/3 place, hind wing long, reaching the base of epiproct. Type specimens are deposited in the College of Plant Protection, Shandong Agricultural University, Taian, Shandong 271018, China.

8.
Med Sci Monit ; 24: 5064-5070, 2018 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-30030914

RESUMO

BACKGROUND Long noncoding RNAs (lncRNAs) recently have been implicated in the pathological processes of cardiovascular diseases. In this study, LncRNADisease database and PubMed database were used to screen myocardial infraction (MI)-related lncRNAs and to investigate the diagnostic role of lncRNAs in ST-segment elevation myocardial infraction (STEMI). MATERIAL AND METHODS Forty-six patients with STEMI and 40 healthy controls were included in the study. Venous blood samples acquired at different time points and the expression levels of lncRNAs in plasma were measured by qRT-PCR. In addition, other blood samples were collected before and after percutaneous coronary intervention (PCI). Correlation analysis and receiver operating characteristic (ROC) curve were used to assess the diagnosis value of the markers. All included patients were followed up for 12±1 months. RESULTS Nine MI-related lncRNAs were selected from the database. The qRT-PCR results showed that the expression of hypoxia inducible factor 1A antisense RNA 2 (aHIF), member 1 opposite strand/antisense transcript 1 (KCNQ1OT1), and mitochondrial long noncoding RNA uc022bqs.1 (LIPCAR) were significantly increased in patients with STEMI compared to the control patients. The ROC curve showed that LIPCAR (AUC=0.782, 95% CI: 0.707-0.0.894) had better diagnostic accuracy. Moreover, correlation analysis indicated that LIPCAR were positively correlated with myocardial enzymes and negatively correlated with left ventricular ejection fraction. The level of LIPCAR in STEMI patients after PCI was lower (P<0.05). Multivariate regression analysis indicated that higher levels of LIPCAR were independent predictors of major adverse cardiovascular events in patients with STEMI (HR=5.93; 95% CI, 1.46-9.77; P=0.001). CONCLUSIONS Highly expressed LIPCAR in plasma may serve as a warning sign for the diagnosis of STEMI.


Assuntos
Infarto do Miocárdio/genética , Intervenção Coronária Percutânea , RNA Longo não Codificante/sangue , Infarto do Miocárdio com Supradesnível do Segmento ST/genética , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estudos de Casos e Controles , Ácidos Nucleicos Livres/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Valor Preditivo dos Testes , Curva ROC , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia
9.
Medicine (Baltimore) ; 97(27): e11444, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29979445

RESUMO

BACKGROUND: Dexmedetomidine can inhibit the perioperative stress response, which plays an important role in postoperative hypercoagulability. This study aimed to investigate whether dexmedetomidine could attenuate the activation of postoperative coagulation. METHODS: Patients undergoing open radical gastrectomy under total intravenous anesthesia were randomly allocated to the control group (group Con) and the dexmedetomidine group (group Dex). Dexmedetomidine was intravenously infused at 0.5 µg/kg over 10 minutes before anesthesia induction and then infused at a rate of 0.5 µg/kg/h until peritoneal closure in group Dex, whereas saline was administered in group Con. Blood samples were collected for thrombelastograph (TEG) analysis [reaction time (R time), clot formation time (K time), and clot formation rate (α angle)] and laboratory coagulation testing before dexmedetomidine administration and at the end of surgery. RESULTS: Coagulation was activated after radical gastrectomy, as indicated by TEG analysis and the increased concentrations of plasma fibrin (fibrinogen) degradation product (FDP) and thrombin-antithrombin complex (TAT). The R and K times were significantly prolonged and α angle was significantly decreased in group Dex compared with that in group Con at the end of surgery (P < .05). The concentrations of plasma TAT and FDP in group Dex were significantly lower than those in group Con at the end of surgery (P < .05 or .01). CONCLUSION: Adjunctive dexmedetomidine with general anesthesia attenuates the activation of coagulation following radical gastrectomy.


Assuntos
Anestesia Geral/efeitos adversos , Dexmedetomidina/uso terapêutico , Gastrectomia/efeitos adversos , Hipnóticos e Sedativos/uso terapêutico , Trombofilia/prevenção & controle , Idoso , Período de Recuperação da Anestesia , Coagulação Sanguínea/efeitos dos fármacos , Testes de Coagulação Sanguínea/métodos , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/tratamento farmacológico , Estudos Prospectivos , Tromboelastografia/efeitos dos fármacos , Tromboelastografia/métodos , Trombofilia/etiologia
10.
Biomed Pharmacother ; 103: 1664-1668, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29864956

RESUMO

A capsule of Qili Jiegu, a traditional Chinese medicine with numerous biological activities, may exert a protective eff ;ect against postmenopausal bone loss. However, it remains unclear whether Qili Jiegu-containing serum regulates the osteogenic diff ;erentiation of bone marrow stromal cells (BMSCs) in vitro. In this study, BMSCs were treated with medium and Qili Jiegu-containing serum over a 14-day period. We found that Qili Jiegu-containing serum promoted the BMSC proliferation and alkaline phosphatase (ALP) activities, as well as stimulated the expression of osteogenic markers and Wnt/ß-catenin pathway-related genes, i.e., runt-related transcription factor 2 (Runx2), osteocalcin (OCN), ß-catenin and Wnt4a, in BMSCs. Finally, we found that Qili Jiegu-containing serum activated the Wnt/ß-catenin pathway. An addition of Dickkopf-related protein-1 (an inhibitor of the Wnt/ß-catenin signaling pathway) to the Qili Jiegu-containing serum could decrease the stimulatory osteogenic effect of Qili Jiegu-containing serum on BMSCs. Therefore, Qili Jiegu-containing serum could promote the osteogenic diff ;erentiation of BMSCs, and the potential mechanism may involve regulation of Wnt/ß-catenin signaling.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Animais , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células , Feminino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Transporte Proteico/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , beta Catenina/metabolismo
11.
J Geriatr Cardiol ; 15(3): 229-234, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29721002

RESUMO

Hypertension has been found to be increased a risk of stroke in atrial fibrillation (AF). Both the European and U.S. guidelines advocate the use of the CHA2DS2-VASc (congestive heart failure, hypertension, age > 75 years, diabetes mellitus, stroke/transient ischemic attack, vascular disease, age 65-74 years, sex category) scheme for risk stratification. Although vitamin K antagonists is more effective than acetylsalicylic acid at preventing ischaemic stroke, its benefit is offs by an increased haemorrhage risk. The risk of ischemic stroke in patients with AF and a CHA2DS2-VASc score of 1 are considered to be low risk and may be not expected to benefit from anticoagulation therapy. Hypertension carries an increased risk of ischemic stroke, however, it is also a clear risk factor for hemorrhage in AF. Therefore, the optimal antithrombotic management is highlighted in patients with AF with only one risk factor especially hypertension.

12.
J Thorac Dis ; 9(9): 2898-2903, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29221261

RESUMO

Background: This study aims to investigate the clinical and angiographic features in patients with acute myocardial infarction (AMI) induced by coronary artery embolism. Methods: Clinical data of five patients with AMI induced by coronary artery embolism were analyzed retrospectively. Results: One patient had left atrial myxoma, one patient had non-valvular atrial fibrillation, and three patients had rheumatic heart disease. Furthermore, one patient had mitral mechanical valve prostheses, two patients had atrial fibrillation. Coronary angiography showed the absence of significant atherosclerostic lesions in the coronary arteries except infarct related artery in five patients. Angiography suggested the presence of IRA occlusion caused by embolism. Conclusions: The status for AMI due to coronary artery embolism usually expresses embolic material originating from the left heart chambers. Rheumatic heart disease and atrial fibrillation are the common reasons for coronary artery embolism. Coronary artery occlusion is the common performance in the results of primary coronary artery angiography. Sometimes it expresses visible signs of embolism.

13.
Plant Mol Biol ; 95(4-5): 425-439, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28924726

RESUMO

Nuclear factor Y (NF-Y) family proteins are involved in many developmental processes and responses to environmental cues in plants, but whether and how they regulate phytohormone abscisic acid (ABA) signaling need further studies. In the present study, we showed that over-expression of the NF-YC9 gene confers ABA hypersensitivity in both the early seedling growth and stomatal response, while down-regulation of NF-YC9 does not affect ABA response in these processes. We also showed that over-expression of the NF-YC9 gene confers salt and osmotic hypersensitivity in early seedling growth, which is likely to be directly associated with the ABA hypersensitivity. Further, we observed that NF-YC9 physically interacts with the ABA-responsive bZIP transcription factor ABA-INSENSITIVE5 (ABI5), and facilitates the function of ABI5 to bind and activate the promoter of a target gene EM6. Additionally, NF-YC9 up-regulates expression of the ABI5 gene in response to ABA. These findings show that NF-YC9 may be involved in ABA signaling as a positive regulator and likely functions redundantly together with other NF-YC members, and support the model that the NF-YC9 mediates ABA signaling via targeting to and aiding the ABA-responsive transcription factors such as ABI5.


Assuntos
Ácido Abscísico/farmacologia , Arabidopsis/genética , Fator de Ligação a CCAAT/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Transdução de Sinais , Arabidopsis/efeitos dos fármacos , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fator de Ligação a CCAAT/genética , Expressão Gênica , Fenótipo , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/genética , Estômatos de Plantas/fisiologia , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Protoplastos , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/fisiologia , Tabaco/efeitos dos fármacos , Tabaco/genética , Tabaco/fisiologia
14.
Infect Dis Poverty ; 5(1): 74, 2016 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-27491387

RESUMO

BACKGROUND: The Ebola virus disease spread rapidly in West Africa in 2014, leading to the loss of thousands of lives. Community engagement was one of the key strategies to interrupt Ebola transmission, and practical community level measures needed to be explored in the field and tailored to the specific context of communities. METHODS: First, community-level education on Ebola virus disease (EVD) prevention was launched for the community's social mobilizers in six districts in Sierra Leone beginning in November 2014. Then, from January to May of 2015, in three pilot communities, local trained community members were organized to engage in implementation of EVD prevention and transmission interruption measures, by involving them in alert case report, contact tracing, and social mobilization. The epidemiological indicators of transmission interruption in three study communities were evaluated. RESULTS: A total of 6 016 community social mobilizers from 185 wards were trained by holding 279 workshops in the six districts, and EVD message reached an estimated 631 680 residents. In three pilot communities, 72 EVD alert cases were reported, with 70.8 % of them detected by trained local community members, and 14 EVD cases were finally identified. Contact tracing detected 64.3 % of EVD cases. The median duration of community infectivity for the cases was 1 day. The secondary attack rate was 4.2 %, and no third generation of infection was triggered. No health worker was infected, and no unsafe burial and noncompliance to EVD control measures were recorded. The community-based measures were modeled to reduce 77 EVD cases, and the EVD-free goal was achieved four months earlier in study communities than whole country of Sierra Leone. CONCLUSIONS: The community-based strategy of social mobilization and community engagement was effective in case detection and reducing the extent of Ebola transmission in a country with weak health system. The successfully practical experience to reduce the risk of Ebola transmission in the community with poor resources would potentially be helpful for the global community to fight against the EVD and the other diseases in the future.


Assuntos
Surtos de Doenças/prevenção & controle , Ebolavirus/fisiologia , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/prevenção & controle , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Doença pelo Vírus Ebola/transmissão , Doença pelo Vírus Ebola/virologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Serra Leoa/epidemiologia , Adulto Jovem
15.
J Exp Bot ; 67(17): 5009-27, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27406784

RESUMO

Receptor-like kinases (RLKs) have been reported to regulate many developmental and defense process, but only a few members have been functionally characterized. In the present study, our observations suggest that one of the RLKs, a membrane-localized cysteine-rich receptor-like protein kinase, CRK5, is involved in abscisic acid (ABA) signaling in Arabidopsis thaliana Overexpression of CRK5 increases ABA sensitivity in ABA-induced early seedling growth arrest and promotion of stomatal closure and inhibition of stomatal opening. Interestingly, and importantly, overexpression of CRK5 enhances plant drought tolerance without affecting plant growth at the mature stages and plant productivity. Transgenic lines overexpressing a mutated form of CRK5, CRK5 (K372E) with the change of the 372nd conserved amino acid residue from lysine to glutamic acid in its kinase domain, result in wild-type ABA and drought responses, supporting the role of CRK5 in ABA signaling. The loss-of-function mutation of the CRK5 gene does not affect the ABA response, while overexpression of two homologs of CRK5, CRK4 and CRK19, confers ABA responses, suggesting that these CRK members function redundantly. We further showed that WRKY18, WRKY40 and WRKY60 transcription factors repress the expression of CRK5, and that CRK5 likely functions upstream of ABI2 in ABA signaling. These findings help in understanding the complex ABA signaling network.


Assuntos
Ácido Abscísico/fisiologia , Proteínas de Arabidopsis/fisiologia , Arabidopsis/metabolismo , Reguladores de Crescimento de Planta/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Receptores de Superfície Celular/fisiologia , Arabidopsis/fisiologia , Desidratação/metabolismo , Desidratação/fisiopatologia , Ensaio de Desvio de Mobilidade Eletroforética , Escherichia coli , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase em Tempo Real , Tabaco , Técnicas do Sistema de Duplo-Híbrido
16.
Singapore Med J ; 57(7): 396-400, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27439434

RESUMO

INTRODUCTION: Acute myocardial infarction (AMI) due to unprotected left main coronary artery (ULMCA) disease is clinically catastrophic although it has a low incidence. Studies on the long-term prognosis of these patients are rare. METHODS: From January 1999 to September 2013, 55 patients whose infarct-related artery was the ULMCA were enrolled. Clinical, angiographic and interventional data was collected. Short-term and long-term clinical follow-up results as well as prognostic determinants during hospitalisation and follow-up were analysed. RESULTS: Cardiogenic shock (CS) occurred in 30 (54.5%) patients. During hospitalisation, 22 (40.0%) patients died. Multivariate logistic regression analysis showed that CS (odds ratio [OR] 5.86; p = 0.03), collateral circulation of Grade 2 or 3 (OR 0.14; p = 0.02) and final flow of thrombolysis in myocardial infarction (TIMI) Grade 3 (OR 0.05; p = 0.03) correlated with death during hospitalisation. 33 patients survived to discharge; another seven patients died during the follow-up period of 44.6 ± 31.3 (median 60, range 0.67-117.00) months. The overall mortality rate was 52.7% (n = 29). Kaplan-Meier analysis showed that the total cumulative survival rate was 30.7%. Cox multivariate regression analysis showed that CS during hospitalisation was the only predictor of overall mortality (hazard ratio 4.07, 95% confidence interval 1.40-11.83; p = 0.01). CONCLUSION: AMI caused by ULMCA lesions is complicated by high incidence of CS and mortality. CS, poor collateral blood flow and failure to restore final flow of TIMI Grade 3 correlated with death during hospitalisation. CS is the only predictor of long-term overall mortality.


Assuntos
Doença da Artéria Coronariana/terapia , Vasos Coronários/patologia , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/terapia , Adulto , Idoso , Angiografia , Angioplastia Coronária com Balão , Doença da Artéria Coronariana/patologia , Feminino , Seguimentos , Hospitalização , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Intervenção Coronária Percutânea , Prognóstico , Modelos de Riscos Proporcionais , Análise de Regressão , Estudos Retrospectivos , Choque Cardiogênico , Adulto Jovem
17.
Plant Mol Biol ; 90(3): 267-79, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26646286

RESUMO

Although a lot of genes have been revealed to participate in abscisic acid (ABA) signaling, many of the additional components involved in ABA signaling remain to be discovered. Here we report that overexpression of MYB37, a R2R3 MYB subgroup 14 transcription factor in Arabidopsis thaliana, confers hypersensitive phenotypes to exogenous ABA in all the major ABA responses, including ABA-induced inhibition of seed germination, cotyledon greening and early seedling growth, and ABA-induced stomatal closure and inhibition of stomatal opening. Interestingly and importantly, MYB37-overexpression improves plant tolerance to drought, enhances growth of mature plants and seed productivity, thought it delays flowering, which suggests that this gene may be used for improving crop adaptability to drought environment and productivity. However, a myb37-1 knockout mutant displays wild-type ABA responses most likely due to a functional redundancy of the multiple MYB members. Real-time PCR analysis shows that upregulation of the MYB37 expression changes expression of a subset of ABA-responsive genes. Together, these findings suggest that the MYB37 transcription factor plays an important, positive role in plant response to ABA and drought stress, and meanwhile, it plays a positive role in the regulation of seed production.


Assuntos
Ácido Abscísico/farmacologia , Proteínas de Arabidopsis/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Secas , Flores/efeitos dos fármacos , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Germinação/efeitos dos fármacos , Germinação/genética , Sementes/efeitos dos fármacos , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Fatores de Transcrição/genética
18.
PLoS One ; 10(10): e0139741, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26430770

RESUMO

The dengue virus (DENV) envelope protein domain III (ED3) has been suggested to contain receptor recognition sites and the critical neutralizing epitopes. Up to date, relatively little work has been done on fine mapping of neutralizing epitopes on ED3 for DENV4. In this study, a novel mouse type-specific neutralizing antibody 1G6 against DENV4 was obtained with both prophylactic and therapeutic effects. The epitope was mapped to residues 387-390 of DENV4 envelope protein. Furthermore, site-directed mutagenesis assay identified two critical residues (T388 and H390). The epitope is variable among different DENV serotypes but is highly conserved among four DENV4 genotypes. Affinity measurement showed that naturally occurring variations in ED3 outside the epitope region did not alter the binding of mAb 1G6. These findings expand our understanding of the interactions between neutralizing antibodies and the DENV4 and may be valuable for rational design of DENV vaccines and antiviral drugs.


Assuntos
Vírus da Dengue/imunologia , Epitopos/imunologia , Testes de Neutralização , Animais , Linhagem Celular , Cricetinae , Proteínas do Envelope Viral/imunologia
19.
J Exp Bot ; 66(20): 6355-69, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26175350

RESUMO

Magnesium-chelatase H subunit [CHLH/putative abscisic acid (ABA) receptor ABAR] positively regulates guard cell signalling in response to ABA, but the molecular mechanism remains largely unknown. A member of the sucrose nonfermenting 1 (SNF1)-related protein kinase 2 family, SnRK2.6/open stomata 1 (OST1)/SRK2E, which plays a critical role in ABA signalling in Arabidopsis guard cells, interacts with ABAR/CHLH. Neither mutation nor over-expression of the ABAR gene affects significantly ABA-insensitive phenotypes of stomatal movement in the OST1 knockout mutant allele srk2e. However, OST1 over-expression suppresses ABA-insensitive phenotypes of the ABAR mutant allele cch in stomatal movement. These genetic data support that OST1 functions downstream of ABAR in ABA signalling in guard cells. Consistent with this, ABAR protein is phosphorylated, but independently of the OST1 protein kinase. Two ABAR mutant alleles, cch and rtl1, show ABA insensitivity in ABA-induced reactive oxygen species and nitric oxide production, as well as in ABA-activated phosphorylation of a K(+) inward channel KAT1 in guard cells, which is consistent with that observed in the pyr1 pyl1 pyl2 pyl4 quadruple mutant of the well-characterized ABA receptor PYR/PYL/RCAR family acting upstream of OST1. These findings suggest that ABAR shares, at least in part, downstream signalling components with PYR/PYL/RCAR receptors for ABA in guard cells; though cch and rtl1 show strong ABA-insensitive phenotypes in both ABA-induced stomatal closure and inhibition of stomatal opening, while the pyr1 pyl1 pyl2 pyl4 quadruple mutant shows strong ABA insensitivity only in ABA-induced stomatal closure. These data establish a link between ABAR/CHLH and SnRK2.6/OST1 in guard cell signalling in response to ABA.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/fisiologia , Liases/genética , Estômatos de Plantas/fisiologia , Proteínas Quinases/genética , Ácido Abscísico/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Liases/metabolismo , Mutação , Óxido Nítrico/metabolismo , Fosforilação , Estômatos de Plantas/genética , Proteínas Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
20.
Plant Mol Biol ; 88(4-5): 369-85, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26093896

RESUMO

Whereas several mitochondrial/chloroplast pentatricopeptide repeat (PPR) proteins have been reported to regulate plant responses to abiotic stresses, no nucleus-localized PPR protein has been found to play role in these processes. In the present experiment, we provide evidence that a cytosol-nucleus dual-localized PPR protein SOAR1, functioning to negatively regulate abscisic acid (ABA) signaling in seed germination and postgermination growth, is a crucial, positive regulator of plant response to abiotic stresses. Downregulation of SOAR1 expression reduces, but upregulation of SOAR1 expression enhances, ABA sensitivity in ABA-induced promotion of stomatal closure and inhibition of stomatal opening, and plant tolerance to multiple, major abiotic stresses including drought, high salinity and low temperature. Interestingly and importantly, the SOAR1-overexpression lines display strong abilities to tolerate drought, salt and cold stresses, with surprisingly high resistance to salt stress in germination and postgermination growth of seeds that are able to potentially germinate in seawater, while no negative effect on plant growth and development was observed. So, the SOAR1 gene is likely useful for improvement of crops by transgenic manipulation to enhance crop productivity in stressful conditions. Further experimental data suggest that SOAR1 likely regulates plant stress responses at least partly by integrating ABA-dependent and independent signaling pathways, which is different from the ABI2/ABI1 type 2C protein phosphatase-mediated ABA signaling. These findings help to understand highly complicated stress and ABA signalling network.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/fisiologia , Arabidopsis/genética , Arabidopsis/fisiologia , Ácido Abscísico/fisiologia , Aclimatação/genética , Aclimatação/fisiologia , Arabidopsis/crescimento & desenvolvimento , Temperatura Baixa/efeitos adversos , Secas , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Germinação/genética , Germinação/fisiologia , Pressão Osmótica , Reguladores de Crescimento de Planta/fisiologia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase em Tempo Real , Salinidade , Transdução de Sinais , Estresse Fisiológico/genética
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