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1.
Plant Dis ; 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37700470

RESUMO

Ficus hirta Vahl. is a Moraceae plant, named for its palm-like leaves. It is a widely used traditional medicinal material with definite curative effect. At the same time, it is also a commonly used soup material among the folk in South China. In March 2022, a serious leaf spot disease with symptoms similar to anthracnose was observed on F. hirta in several plantations in Qinzhou and Zhanjiang City of China, with an incidence of 32~65%. The early symptoms of infected leaves were small, round, yellow spots that further expanded into larger, brown, irregular, necrotic lesions surrounded by dark brown edges, which eventually led to leaf wilt. Twenty symptomatic leaves were collected from three plantations with a total area of about 10 hm2. Fragments (2×2 mm) from the 20 infected leaves were surface sterilized, plated on potato dextrose agar (PDA) and incubated at 28°C. After 3 days, isolates with similar cultural morphology were obtained and three representative isolates (WZMT-1, WZMT-3 and WZMT-8) were randomly selected for following study. The colonies by single-spore purification on PDA were initially cottony, pale white and became grayish green with age. The conidia were hyaline, abundant, cylindrical, with rounded ends, 14.4~18.2 µm×4.6~6.0 µm (av. 16.2 µm×5.4 µm, n=100). Conidiogenous cells hyaline, cylindrical or ampulliform, 6.2~22.7 µm × 2.7~5.0 µm (av. 12.9 µm×3.8 µm, n=50). Appressoria were brown to dark brown, ovoid to clavate, elliptical or irregular, 7.9~13.4 µm × 5.6~9.2 µm (av. 10.6 µm×7.9 µm, n=50). The morphology of the fungus resembled Colletotrichum fructicola (Prihastuti et al. 2009). For molecular identification, the internal transcribed spacer (ITS) regions, glyceraldehyde-3-phosphatedehydrogenase (GAPDH), actin (ACT), beta-tubulin 2 (TUB2), calmodulin (CAL), partial manganese superoxide dismutase (sod2), partial Apn2-Mat1-2 intergenic spacer and partial mating type (Mat1-2) (ApMat) genes were amplified from genomic DNA for the isolates using the primers described by Silva et al. (2012) and Weir et al. (2012). The sequences of the above seven loci of the three isolates (accession nos. OQ121661 to OQ121663 and OQ133400 to OQ133417) were obtained and showed over 99% identity with the existing sequences of ex-type culture ICMP 18581 of Colletotrichum fructicola (Weir et al. 2012). A multilocus phylogenetic analysis of the seven loci concatenated sequences using the maximum likelihood method revealed that the isolates belong to C. fructicola. To confirm pathogenicity, five 3-month-old potted plants were used for inoculation with each representative isolate. Tested plants were sprayed with 10 ml of a conidial suspension (1 × 108 conidia/ml) , and the controls plants were sprayed with sterile water. All the plants were incubated in a growth chamber at 26 ± 2°C with 95% relative humidity. After 10 days, typical lesions like those observed on the field plants appeared on all inoculated plants, while the control remained healthy. The same fungal pathogen was reisolated and the identity was confirmed by morphological characterization and molecular analysis, confirming Koch's postulates. The pathogen has been reported as the causal agent of anthracnose on a wide range of plant hosts worldwide (Marquez-Zequera et al. 2018; Horfer et al. 2021; Jiang et al. 2022; Li et al. 2023). To our knowledge, this is the first report of anthracnose on F. hirta caused by C. fructicola in southern China.

2.
Plant Dis ; 107(12): 3674-3686, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37272043

RESUMO

Vetiver grass (Chrysopogon zizanioides) has been widely used in recent years for ecological environment management, restoration of degraded ecosystems, and essential oil extraction. In 2019, a leaf streak disease of C. zizanioides was observed in Zhanjiang, Guangdong Province, China. The disease appeared as large streak lesions on the leaves, on which conidiomata were formed. A pathogenicity test with the fungus isolated from these lesions confirmed Koch's postulates and thus the fungus as the causal agent of this disease. A morphological resemblance of the pathogen to Stenocarpella was noted upon microscopic examination. Phylogenetic trees inferred from both individual and combined ITS, LSU, and tef1 sequences confirmed the pathogen as a species of the Diaporthaceae and revealed it to be closely related to Phaeocytostroma and Stenocarpella species. As morphological characters clearly placed the pathogen in the genus Stenocarpella, it was described as S. chrysopogonis.


Assuntos
Ascomicetos , Vetiveria , Ecossistema , Filogenia , China
3.
Polymers (Basel) ; 14(13)2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35808762

RESUMO

CF4 has a global warming potential of 6500 and possesses a lifetime of 50,000 years. In this study, we modified the HZSM-5 catalyst with Ce and sulfuric acid treatment. The S/Ce/HZSM-5 catalyst achieves 41% of CF4 conversion at 500 °C, which is four times higher than that over Ce/HZSM-5, while the HZSM-5 exhibits no catalytic activity. The effects of modification were studied by using NH3-TPD, FT-IR of pyridine adsorption, and XPS methods. The results indicated that the modification, especially the sulfuric acid treatment, strongly increased the Lewis acidic sites, strong acidic sites, and moderate acidic sites on catalysts, which are the main active centers for CF4 decomposition. The mechanism of acidic sites increases by modification and CF4 decomposition is clarified. The results of this work will help the development of more effective catalysts for CF4 decomposition.

4.
J Healthc Eng ; 2022: 1960030, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35444777

RESUMO

Diabetes and hypertension are the most common diseases and often coexist. Currently, hypertension is the most widespread chronic disease in China. To explore the value of three-dimensional team management in improving the effect of the management of primary diabetes and hypertension in patients in the medical community model, the expert team at the Department of Cardiology and Endocrinology of Anji County People's Hospital is selected to train 59 community general practitioners in the medical community model (the study group adopts the three-dimensional team management model in the medical community model), and another 59 community medical general practitioners adopts the conventional training method (the control group). The two groups of doctors managed patients with diabetes and hypertension who are registered in the jurisdiction (200 patients per group) as per the respective training methods. The three-dimensional management of the team under the medical community model significantly improves the diagnostic and treatment capabilities of grassroot general practitioners to better control patients' diabetes and hypertension levels.


Assuntos
Cardiologia , Diabetes Mellitus , Endocrinologia , Hipertensão , Médicos , Diabetes Mellitus/terapia , Humanos , Hipertensão/terapia
5.
Nonlinear Dyn ; 101(3): 1527-1543, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32836818

RESUMO

COVID-19 was declared as a pandemic by the World Health Organization on March 11, 2020. Here, the dynamics of this epidemic is studied by using a generalized logistic function model and extended compartmental models with and without delays. For a chosen population, it is shown as to how forecasting may be done on the spreading of the infection by using a generalized logistic function model, which can be interpreted as a basic compartmental model. In an extended compartmental model, which is a modified form of the SEIQR model, the population is divided into susceptible, exposed, infectious, quarantined, and removed (recovered or dead) compartments, and a set of delay integral equations is used to describe the system dynamics. Time-varying infection rates are allowed in the model to capture the responses to control measures taken, and distributed delay distributions are used to capture variability in individual responses to an infection. The constructed extended compartmental model is a nonlinear dynamical system with distributed delays and time-varying parameters. The critical role of data is elucidated, and it is discussed as to how the compartmental model can be used to capture responses to various measures including quarantining. Data for different parts of the world are considered, and comparisons are also made in terms of the reproductive number. The obtained results can be useful for furthering the understanding of disease dynamics as well as for planning purposes.

6.
Environ Sci Pollut Res Int ; 27(32): 40504-40511, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32666441

RESUMO

Hydroxyl radical (•OH)-based advanced oxidation technologies (AOTs) is an effective and clean way to remove sulfonamide antibiotics in water at ambient temperature and pressure. In this study, we systematically investigated the degradation kinetics of sulfamethazine (SMT) by •OH with a combination of experimental and theoretical approaches. The second-order rate constant (k) of SMT with •OH was experimentally determined to be 5.27 ± 0.06 × 109 M-1 s-1 at pH 4.5. We also calculated the thermodynamic and kinetic behaviors for the reactions by density functional theory (DFT) using the B3LYP/6-31G*. The results revealed that •OH addition pathways at the methylene (C4) site on the pyridine ring and the ortho sites (C12 and C14) of the amino group on the benzene ring dominate the reaction, especially C14 site on the benzene ring accounted for 43.95% of SMT degradation kinetics. The theoretical k value which was calculated by conventional transition state theory is 3.96 × 109 M-1 s-1, indicating that experimental observation (5.27 ± 0.06 × 109) is correct. These results could further help AOTs design in treating sulfonamide during wastewater treatment processes.


Assuntos
Radical Hidroxila , Poluentes Químicos da Água , Peróxido de Hidrogênio , Cinética , Modelos Teóricos , Oxirredução , Sulfametazina
7.
Emerg Med J ; 37(4): 232-239, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31836584

RESUMO

OBJECTIVES: To carry out a meta-analysis to examine the prognostic performance of the Mortality in Emergency Department Sepsis (MEDS) score in predicting mortality among emergency department patients with a suspected infection. METHODS: Electronic databases-PubMed, Embase, Scopus, EBSCO and the Cochrane Library-were searched for eligible articles from their respective inception through February 2019. Sensitivity, specificity, likelihood ratios and receiver operator characteristic area under the curve were calculated. Subgroup analyses were performed to explore the prognostic performance of MEDS in selected populations. RESULTS: We identified 24 studies involving 21 246 participants. The pooled sensitivity of MEDS to predict mortality was 79% (95% CI 72% to 84%); specificity was 74% (95% CI 68% to 80%); positive likelihood ratio 3.07 (95% CI 2.47 to 3.82); negative likelihood ratio 0.29 (95% CI 0.22 to 0.37) and area under the curve 0.83 (95% CI 0.80 to 0.86). Significant heterogeneity was seen among included studies. Meta-regression analyses showed that the time at which the MEDS score was measured and the cut-off value used were important sources of heterogeneity. CONCLUSION: The MEDS score has moderate accuracy in predicting mortality among emergency department patients with a suspected infection. A study comparison MEDS and qSOFA in the same population is needed.


Assuntos
Infecções/mortalidade , Índice de Gravidade de Doença , Área Sob a Curva , Regras de Decisão Clínica , Serviço Hospitalar de Emergência/organização & administração , Humanos , Infecções/diagnóstico , Escores de Disfunção Orgânica , Curva ROC
8.
J Anal Methods Chem ; 2016: 4515673, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27069713

RESUMO

The spatial variation and distribution features of the metals tested in the surface runoff in Xikuangshan Bao Daxing miming area were analyzed by combining statistical methods with a geographic information system (GIS). The results showed that the maximum concentrations of those five kinds of the metals (Sb, Zn, Cu, Pb, and Cd) in the surface runoff of the antimony mining area were lower than the standard value except the concentration of metal Ni. Their concentrations were 497.1, 2.0, 1.8, 22.2, and 22.1 times larger than the standard value, respectively. This metal pollution was mainly concentrated in local areas, which were seriously polluted. The variation coefficient of Sb, Zn, Cu, Ni, Pb, and Cd was between 0.4 to 0.6, wherein the Sb's spatial variability coefficient is 50.56%, indicating a strong variability. Variation coefficients of the rest of metals were less than 50%, suggesting a moderate variability. The spatial structure analysis showed that the squared correlation coefficient (R (2)) of the models fitting for Sb, Zn, Cu, Ni, Pb, and Cd was between 0.721 and 0.976; the ratio of the nugget value (C 0) to the abutment value (C + C 0) was between 0.0767 and 0.559; the semivariogram of Sb, Zn, Ni, and Pb was in agreement with a spherical model, while semivariogram of Cu and Cd was in agreement with Gaussian model, and both had a strong spatial correlation. The trend and spatial distribution indicated that those pollution distributions resulting from Ni, Pb, and Cd are similar, mainly concentrated in both ends of north and south in eastern part. The main reasons for the pollution were attributed to the residents living, transportation, and industrial activities; the Sb distribution was concentrated mainly in the central part, of which the pollution was assigned to the mining and the industrial activity; the pollution distributions of Zn and Cu were similar, mainly concentrated in both ends of north and south as well as in west; the sources of the metals were widely distributed.

9.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 28(4): 461-464, 2016 Mar 11.
Artigo em Chinês | MEDLINE | ID: mdl-29376296

RESUMO

OBJECTIVE: To understand the demands of African students on the China-Africa malaria prevention training programs as well as explore further suggestions on the student selection and course content design. METHODS: A self-administered questionnaire survey was conducted, and all the students who attended in the malaria prevention training courses in 2014 and 2015 were included. The Chi-square test was conducted to analyse the correlations between professional backgrounds, work statues and training needs. RESULTS: A total of 161 individuals were sampled eventually. These participants were trained in either English (58.4%) or French (41.6%). Most of the participants were male (69.3%), the major of them were mainly clinical technology specialty (40.0%), and most of them worked in malaria area within 10 years (56.4%). Moreover, 48.2% of the participants used more than 76% of total work time on malaria control, and more than 80% worked in national or provincial/municipal level. The working areas of these participants were focused on clinical field (41.4%) and official field (29.9%), and only a few of them were from research positions (11.9%). The most needed course content in malaria training was strategy and epidemiology knowledge for malaria prevention and control (65.5%), while clinical workers were most needed to be trained (39.2%). The participants who came from French speaking countries preferred strategy training (χ2 = 12.528, P < 0.01), and those worked in the national level were aslo more likely to choose strategies training course (χ2 = 10.508, P < 0.05). CONCLUSIONS: Currently, the China-Africa malaria prevention training programs could basically satisfy African students'needs. However, more aimed courses should be designed according to their professional backgrounds, national situation, work experiences on malaria control, and institutional levels.


Assuntos
Educação Médica/estatística & dados numéricos , Malária/prevenção & controle , Estudantes , Inquéritos e Questionários , África , China , Feminino , Humanos , Idioma , Masculino
10.
J Anal Methods Chem ; 2015: 163163, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26167333

RESUMO

In order to reveal the influence of the metals of soil-water interface in a manganese mine (Xiangtan, China), on local water environment, there are six kinds of metals (Mn, Ni, Cu, Zn, Cd, and Pb) characterized by measuring their concentration, correlation, source, and special distribution using principal component analysis, single factor, and Nemero comprehensive pollution index. The results showed that the corresponding average concentration was 0.3358, 0.045, 0.0105, 0.0148, 0.0067, and 0.0389 mg/L. The logarithmic concentration of Mn, Zn, and Pb was normal distribution. The correlation coefficients (between Mn and Pb, Mn and Zn, Mn and Ni, Cu and Zn, Cu and Pb, and Zn and Cd) were found to range from 0.5 to 0.6, and those between Cu and Ni and Cu and Cd were below 0.3. It was found that Zn and Mn pollution were caused primarily by ore mining, mineral waste transportation, tailing slag, and smelting plants, while Cu and Ni mainly originate from the mining industry activities and the traffic transportation in the mining area. In addition, the Cd was considered to be produced primarily from the agricultural or anthropogenic activities. The pollution indexes indicated that metal pollution degree was different in soil-water interface streams as listed in increasing order of pollution level as Zn > Ni > Cu > Pb > Mn > Cd. For all of the pollution of the soil-water interface streams, there was moderate metal pollution but along the eastern mine area the pollution seemed to get more serious. There was only a small amount of soil-water interface streams not contaminated by the metals.

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