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1.
J Virol Methods ; : 113795, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31809783

RESUMO

Two reverse-transcription loop-mediated isothermal amplification (RT-LAMP) assays were developed for the detection of areca palm necrotic ringspot virus (ANRSV) and areca palm necrotic spindle-spot virus (ANSSV), respectively. These two emerging viruses both induce necrotic symptoms in areca palms. The coat protein (CP) gene of ANRSV and the 9 K gene of ANSSV were used to design the respective RT-LAMP primers for the assays. Each set of four primers designed for each of these viruses was found to be highly specific in the detection of the respective targeted virus. The optimal incubation conditions for the RT-LAMP assays were 63 °C for 40 min for ANRSV and at 61 °C for 40 min for ANSSV. The sensitivity of the RT-LAMP method for each of these viruses was 10-fold greater than that of the corresponding conventional reverse-transcription polymerase chain reaction (RT-PCR). The RT-LAMP assays may be useful for the rapid early detection of ANSSV and ANRSV in commercial areca palm production.

2.
BMC Public Health ; 16: 335, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-27079376

RESUMO

BACKGROUND: Burnout is a psychosomatic syndrome characterized by three dimensions (emotional exhaustion [EE], feelings of depersonalization [DP], and reduced personal accomplishment [PA]). We determined the prevalence of burnout and mental health status between HIV/AIDS healthcare workers and other healthcare workers, and determined the factors associated with burnout of HIV/AIDS healthcare workers. METHODS: All participants were asked to complete a self-administered questionnaire. The participants were recruited from the departments of infectious diseases in four hospitals which treated HIV/AIDS. The questionnaire included demographics, the Maslach Burnout Inventory-General Survey (MBI-GS), the Symptom Checklist 90 (SCL-90), the Eysenck Personality Questionnaire (EPQ), and the Trait Coping Style Questionnaire (TCSQ). RESULTS: A total of 512 questionnaires were distributed; 501 questionnaires were completed and collected (the response rate was 97.9 %). After eliminating nine invalid questionnaires (1.80 %), 264 physicians and nurses caring for HIV/AIDS and 228 physicians and nurses caring for other infectious diseases provided valid responses (98.2 %). The HIV/AIDS healthcare workers' scores on the emotional exhaustion (F = 6.350, p = 0.012) and depersonalization dimensions (F = 8.533, p = 0.004) were significantly higher than other healthcare workers. The HIV/AIDS healthcare workers had higher total scores and positive items on the Symptom Checklist 90 (SCL-90) compared with other healthcare workers. Low job satisfaction, serious somatization, interpersonal sensitivity, poor quality of sleep, high psychoticism scores, and use of negative coping styles were frequently associated with burnout. CONCLUSIONS: Burnout was shown to be highly prevalent in HIV/AIDS healthcare workers, 76.9 % of whom met the accepted criteria for burnout. In addition, compared with other healthcare workers, HIV/AIDS healthcare workers experienced lower levels of psychological health. Interventions should be targeted at reducing the occurrence of burnout and alleviating psychological pressure amongst HIV/AIDS healthcare workers.


Assuntos
Esgotamento Profissional/epidemiologia , Infecções por HIV/terapia , Enfermeiras e Enfermeiros/psicologia , Médicos/psicologia , Síndrome de Imunodeficiência Adquirida/terapia , Adulto , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros/estatística & dados numéricos , Médicos/estatística & dados numéricos , Prevalência , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
3.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 32(2): 440-5, 2015 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-26211268

RESUMO

The real-time monitoring of cerebral hemorrhage can reduce its disability and fatality rates greatly. On the basis of magnetic induction phase shift, we in this study used filter and amplifier hardware module, NI-PXI data-acquisition system and LabVIEW software to set up an experiment system. We used Band-pass sample method and correlation phase demodulation algorithm in the system. In order to test and evaluate the performance of the system, we carried out saline simulation experiments of brain hemorrhage. We also carried out rabbit cerebral hemorrhage experiments. The results of both saline simulation and animal experiments suggested that our monitoring system had a high phase detection precision, and it needed only about 0.030 4s to finish a single phase shift measurement, and the change of phase shift was directly proportional to the volume of saline or blood. The experimental results were consistent with theory. As a result, this system has the ability of real-time monitoring the progression of cerebral hemorrhage precisely, with many distinguished features, such as low cost, high phase detection precision, high sensitivity of response so that it has showed a good application prospect.


Assuntos
Hemorragia Cerebral/diagnóstico , Magnetismo , Algoritmos , Animais , Sistemas de Computação , Coelhos , Software
4.
Analyst ; 139(24): 6406-13, 2014 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-25325612

RESUMO

In this study, we developed a novel biomimetic electrochemical sensor sensitized with a Fe3O4@carboxyl-functionalized multiwalled carbon nanotube/chitosan nanocomposite layer using a molecularly imprinted film as a recognition element for the rapid detection of acephate and trichlorfon. The performance of the imprinted sensor was investigated using cyclic voltammetry and differential pulse voltammetry, and the results indicated that the sensor exhibited fast responses to both acephate and trichlorfon. The imprinted sensor had good linear current responses to acephate and trichlorfon concentrations in the ranges from 1.0 × 10(-4) to 1.0 × 10(-10) M and 1.0 × 10(-5) to 1.0 × 10(-11) M, respectively. Under optimal conditions, the imprinted sensor had low limits of detection (signal to noise ratio, S/N = 3) of 6.81 × 10(-11) M for acephate and 8.94 × 10(-12) M for trichlorfon. The developed method was successfully applied to detect acephate and trichlorfon spiked in fortified kidney bean and cucumber samples with good recoveries ranging from 85.7% to 94.9% and relative standard deviations of 3.46-5.18%.


Assuntos
Técnicas Eletroquímicas/instrumentação , Inseticidas/análise , Impressão Molecular , Nanocompostos/química , Compostos Organotiofosforados/análise , Triclorfon/análise , Verduras/química , Desenho de Equipamento , Compostos Férricos/química , Limite de Detecção , Nanocompostos/administração & dosagem , Nanotubos de Carbono/química , Fosforamidas
5.
Wei Sheng Wu Xue Bao ; 54(5): 487-97, 2014 May 04.
Artigo em Chinês | MEDLINE | ID: mdl-25199247

RESUMO

Most members of the Burkholderia cepacia complex (Bcc) are important human opportunistic pathogens. Although progress has been achieved on the taxonomy and molecular identification of these bacteria, the molecular mechanisms of Bcc pathogenicity remain unclear and little development is made for new therapeutic agents. As Bcc is resistant to many common clinically-relevant antibiotics, revealing its virulence determinants is therefore very important to develop novel antibiotics or alternative anti-infective therapies. In this review, we summarize current advances in principal virulence determinants, limitations and genetic tools for studies of pathogenesis of Bcc. We primarily focus on key pathogenicity factors, including innate resistance to antibiotics, protein secretion system, and quorum-sensing systems.


Assuntos
Infecções por Burkholderia/microbiologia , Complexo Burkholderia cepacia/patogenicidade , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Complexo Burkholderia cepacia/efeitos dos fármacos , Complexo Burkholderia cepacia/genética , Complexo Burkholderia cepacia/metabolismo , Humanos , Virulência , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
6.
J Sep Sci ; 37(7): 820-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24470377

RESUMO

In this study, γ-Fe2 O3 /chitosan magnetic microspheres were synthesized and evaluated by X-ray diffraction, SEM, thermogravimetric analysis, and static and kinetic adsorption experiments. Results showed that the magnetic microspheres exhibited good adsorption ability, and offered fast kinetics for the adsorption of trichlorfon, methamidophos, malathion, methyl parathion, dimethoate, omethoate, phosphamidon, phorate, isocarbophos, and chlorpyrifos. Based on magnetic separation, a simple method of magnetic SPE coupled to GC for the simultaneous determination of ten trace organophosphate pesticide residues was developed. Under the optimal conditions, the enrichment factor for ten organophosphorus pesticides was 10.1-364.7 and linear range was 0.001-10.0 mg/L. The LOD (S/N = 3) of the method for the ten pesticides was 0.31-3.59 µg/kg. The RSD for three replicate extractions of spiked samples was between 2.5 and 6.3%. The pear and apple samples spiked with ten organophosphate pesticides at 20 and 200 µg/kg levels were extracted and determined by this method with good recoveries ranging from 79.9 to 98.7%. Moreover, the method has been successfully applied for the determination of the ten organophosphate pesticide residues in peach samples.


Assuntos
Quitosana/química , Compostos Férricos/química , Frutas/química , Organofosfatos/análise , Resíduos de Praguicidas/análise , Cromatografia Gasosa , Fenômenos Magnéticos , Microesferas , Estrutura Molecular
7.
J Sci Food Agric ; 94(7): 1409-15, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24122545

RESUMO

BACKGROUND: Organophosphate pesticide residues are harmful to human health because of their potential mutagenic and carcinogenic properties. Therefore, it is of great importance to development an accurate and reliable analytical method to prevent their uncontrolled effects on environmental pollution and human health. RESULTS: This study reports a new method of molecularly imprinted solid-phase extraction coupled with high-performance liquid chromatography (MISPE-HPLC) for simultaneous determination of two organophosphate pesticides residues. Two types of molecularly imprinted polymers (MIPs) were prepared using the trichlorfon and monocrotophos as the template molecule, respectively, methacrylic acid as the functional monomer, and ethylene glycol dimethacrylate as the cross-linker. The recognition ability and adsorption-desorption dynamic of each imprinted polymer toward the trichlorfon or monocrotophos were characterised. Using the mixture of trichlorfon-MIP and monocrotophos-MIP (20:80, wt/wt) as solid-phase extraction sorbent, the factors affecting the pre-concentration on the analytes and the sensitivity of the MISPE-HPLC method were optimised. Under optimal condition, the linear range was 0.005-1.0 mg L⁻¹. The limit of detection was 4.2 µg g⁻¹ for trichlorfon, and 1.2 ng g⁻¹ for monocrotophos. The peak area precision [Relative standard deviation (RSD)] for three replicates was 2.9-4.5%. The blank rape and cauliflower samples spiked with trichlorfon and monocrotophos at 0.05 and 0.005 µg g⁻¹ levels were extracted and determined by this method with recoveries ranging from 88.5% to 94.2%. Moreover, this method was successfully applied to the quantitative detection of the trichlorfon and monocrotophos residues in leek samples. CONCLUSION: With good properties of high sensitivity, simple pre-treatment and low cost, this MISPE-HPLC method could provide a new tool for the rapid determination of multi-pesticide residues in the complicated food samples.


Assuntos
Contaminação de Alimentos , Inspeção de Alimentos/métodos , Inseticidas/análise , Monocrotofós/análise , Resíduos de Praguicidas/análise , Triclorfon/análise , Verduras/química , Brassica/química , Brassica rapa/química , Carcinógenos Ambientais/análise , China , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Impressão Molecular , Mutagênicos/análise , Cebolas/química , Reprodutibilidade dos Testes , Extração em Fase Sólida
8.
Biosens Bioelectron ; 52: 374-8, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24084165

RESUMO

Cerebral hemorrhage, which is an important clinical problem, is often monitored and studied using expensive devices, such as magnetic resonance imaging (MRI) and positron emission tomography (PET) that are unavailable in economically underdeveloped regions. Magnetic induction tomography (MIT) is a new type of non-contact, non-invasive, and low-cost detection technology, and exhibits prospects for wide application, especially for the detection of brain diseases. However, the previous studies on MIT have focused on laboratory models and rarely on in vivo applications because the induced signals produced by biological tissues are notably weak. Based on the symmetry between the two brain hemispheres and the fact that a local brain hemorrhage will not affect the contra-lateral hemisphere, a symmetric cancellation-type sensor detection system, which is characterized by one excitation coil and two receiving coils, was designed to improve the detection sensitivity of MIT. This method was subsequently used to detect the occurrence of cerebral hematomas in rabbits. The average phase drift induced by a 3-ml injection of autologous blood was 1.885°, which is a fivefold improvement compared with the traditional single excitation coil and single receiving coil method. The results indicate that this system has high sensitivity and anti-interference ability and high practical value.


Assuntos
Hemorragia Cerebral/diagnóstico por imagem , Magnetismo/métodos , Tomografia/métodos , Animais , Técnicas Biossensoriais , Hemorragia Cerebral/patologia , Humanos , Imagem por Ressonância Magnética , Magnetismo/instrumentação , Coelhos , Radiografia , Software
9.
Bioresour Technol ; 149: 420-4, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24128405

RESUMO

Novel biosorbent materials (RH-2 and RH-3) obtained from agricultural waste materials rice husks (RH-1) were successfully developed through fast and facile esterification reactions with hydroxylethylidenediphosphonic acid and nitrilotrimethylenetriphosphonic acid, respectively. The present paper reported the feasibility of using RH-1, RH-2 and RH-3 for removal of heavy metals from simulated wastewater, the results revealed that the adsorption property of functionalized rice husks with organotriphosphonic acid RH-3 for Au(III) was very excellent, especially for gold ions. The combined effect of initial solution pH, RH-3 dosage and initial Au(III) concentration was investigated using response surface methodology (RSM), the results showed that initial Au(III) concentration exerted stronger influence on Au(III) uptake than initial pH and biomass dosage. The analysis of variance (ANOVA) of the quadratic model demonstrated that the model was highly significant, and under the optimum process conditions, the maximum adsorption capacity could reach 3.25 ± 0.07 mmol/g that is higher than other reported adsorbents.


Assuntos
Metais Pesados/isolamento & purificação , Oryza/química , Ácidos Fosforosos/química , Resíduos/análise , Purificação da Água/economia , Purificação da Água/métodos , Adsorção , Análise de Variância , Custos e Análise de Custo , Ouro , Íons/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Bioresour Technol ; 140: 146-51, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23688666

RESUMO

An efficient bifunctional catalyst lipase/organophosphonic acid-functionalized silica (SG-T-P-LS) has been successfully developed, and biodiesel production of fatty acid ethyl ester (FAEE) from free fatty acid (FFA) oleic acid with short-chain alcohol ethanol catalyzed by SG-T-P-LS was investigated. The process optimization using response surface methodology (RSM) was performed and the interactions between the operational variables were elucidated, and it was found that the molar ratio of alcohol to acid was the most significant factor. The optimum values for maximum conversion ratio can be obtained by using a Box-Behnken center-united design, and the conversion ratio could reach 89.94 ± 0.42% under the conditions that ethanol/acid molar ratio was 1.05:1 and SG-T-P-LS to FFA weight ratio was 14.9 wt.% at 28.6°C. The research results show that SG-T-P and LS-20 could work cooperatively to promote the esterification reaction, and the bifunctional catalyst SG-T-P-LS is a potential catalyst for biodiesel production.


Assuntos
Biocatálise , Biocombustíveis , Biotecnologia/métodos , Etanol/química , Lipase/metabolismo , Ácido Oleico/química , Organofosfonatos/química , Análise de Variância , Esterificação , Microscopia Eletrônica de Varredura , Modelos Teóricos , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Mol Plant Microbe Interact ; 23(4): 425-35, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20192830

RESUMO

At least 12 avirulence genes have been genetically identified and mapped in Phytophthora sojae, an oomycete pathogen causing root and stem rot of soybean. Previously, the Avr4 and Avr6 genes of P. sojae were genetically mapped within a 24 kb interval of the genome. Here, we identify Avr4 and Avr6 and show that they are actually a single gene, Avr4/6, located near the 24-kb region. Avr4/6 encodes a secreted protein of 123 amino acids with an RXLR-dEER protein translocation motif. Transient expression of Avr4/6 in soybean leaves revealed that its gene product could trigger a hypersensitive response (HR) in the presence of either Rps4 or Rps6. Silencing Avr4/6 in P. sojae stable transformants abolished the avirulence phenotype exhibited on both Rps4 and Rps6 soybean cultivars. The N terminus of Avr4/6, including the dEER motif, is sufficient to trigger Rps4-dependent HR while its C terminus is sufficient to trigger Rps6-mediated HR. Compared with alleles from avirulent races, alleles of Avr4/6 from virulent races possess nucleotide substitutions in the 5' untranslated region of the gene but not in the protein-coding region.


Assuntos
Phytophthora/metabolismo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Soja/genética , Alelos , Sequência de Bases , Morte Celular , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Dados de Sequência Molecular , Phytophthora/genética , Phytophthora/patogenicidade , Polimorfismo Genético , Soja/metabolismo , Transcrição Genética , Virulência
12.
Plant Dis ; 94(7): 881-884, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30743553

RESUMO

Phytophthora sojae causes root and stem rot, one of the most devastating diseases of soybean worldwide. In Heilongjiang and Fujian provinces in China, serious cases of Phytophthora stem and root rot have occurred and caused heavy losses in the past several years. To determine the current population status of this pathogen, we investigated the pathogen's distribution, pathotypes, and metalaxyl sensitivity in both provinces. P. sojae was baited and isolated from 258 soil samples in both provinces using the soybean leaf bait method. The pathotypes of all isolates were characterized on 13 differential soybean cultivars using the hypocotyl slit inoculation method, and the sensitivity of all isolates to metalaxyl was tested in vitro. In all, 75 isolates were recovered from 75 fields in 33 counties; of these, 31 counties were in Heilongjiang Province and 2 counties were in Fujian Province. Thirty-five new pathotypes were identified compared with the previously defined races. Less than 5% of the isolates were virulent to cultivars with individual Rps genes 1a, 1c, or 1k. No metalaxyl-resistant isolates were found; the half maximal effective concentration values of all isolates ranged from 0.04 to 0.22 µg ml-1. These results suggest that effective management of the disease in both provinces can be accomplished through the use of resistant cultivars with Rps genes 1a, 1c, or 1k and the fungicide metalaxyl.

13.
Cytotechnology ; 54(2): 97-105, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19003024

RESUMO

The relation between autophagy and apoptosis has not been clearly elucidated. Here, we reported that apoptosis followed autophagy in insect Spodoptera litura cells (Sl) undergoing glucose starvation. Sl cells have been adapted to Leibovitz-15 medium supplemented with glucose (1.0 g/l) and 5% fetal bovine serum (FBS), used for mammalian cell cultures. If glucose (1 g/l) or glutamine (1.6 g/l) had not been supplemented in L-15 medium with 5% FBS, Sl cells began to form many vacuoles and these vacuoles gradually enlarged in the cytoplasm, which were autophagic vacuoles. However, these large vacuoles began to disappear gradually after 48 h of glucose starvation, accompanied with remarkable apoptosis without apoptotic bodies, which was demonstrated by DNA fragmentation and activation of caspase-3-like. During glucose starvation, Sl cell ATP concentrations gradually decreased. Interestingly, if the conditioned L-15 medium without glucose was replaced with fresh L-15 medium supplemented with glucose or glutamine after the cultures had been starved seriously for 48 h or longer, the formation of apoptotic bodies was initiated. These data suggested that the partial depletion of cell ATP triggered apoptosis following autophagy in glucose-starved Sl cells and the formation of apoptotic bodies required higher level of ATP than DNA fragmentation and activation of caspase-3-like activity. Additionally, the disappearance of autophagic vacuoles, negative staining of neutral red, green staining of acridine orange and diffusion of acid phosphatase activity in Sl cells at the late stage of starvation (over 48 h) suggested that the dysfunction of lysosome was more likely to involve in apoptosis. The facts that Actinomycin D-induced apoptosis was partially inhibited and cyclosporin A, blocking the opening of mitochondrial permeability transition (MPT) pores, inhibited partially apoptosis in glucose-starved Sl cells, suggested the pathway of glucose starvation-induced apoptosis seemed to be different from that induced by actinomycin D and the opening of MPT pores on mitochondria probably involved in apoptosis triggered by glucose starvation, respectively.

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