Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 118
Filtrar
1.
PLoS One ; 19(6): e0297127, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38889123

RESUMO

China's "the Belt and Road Initiative" (BRI) is a top-level cooperation initiative among countries proposed by China, which has promoted China's cooperation with relevant countries in various aspects and fields. Research reports from think tanks and experts on the evaluation, analysis, and research conclusions of the BRI can reflect the stance, opinions, and demands of various countries abroad regarding the initiative. This paper takes the BRI reports of important think tanks in the " Global Go To Think Tank Index Report 2020" as the subject of its research, and analyzes the key points and development trends of foreign think tank research on the BRI by using text mining, topic evolution, and social network analysis. It provides reasonable suggestions and ideas for promoting the construction of the BRI and deepening related cooperation in China. Research shows that the thematic distribution of research reports on the BRI by think tanks is mainly focused on the fields of politics, economy, and military. The research areas are relatively stable, and there is not a strong trend of thematic evolution. The evolution paths are also mainly distributed in the fields of politics, economy, and military. There are not many expansions in the thematic evolution directions over the years, and there is a strong inheritance of themes. The connection between research themes and the main purpose of the BRI is somewhat inadequate, indicating a certain limitation in the understanding of the BRI.


Assuntos
Cooperação Internacional , China , Humanos , Mineração de Dados
3.
J Opt Soc Am A Opt Image Sci Vis ; 40(9): 1654-1661, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37707002

RESUMO

A memory-efficient implementation scheme for the discontinuous Galerkin volume integral equation method (DGVIE) using Schaubert-Wilton-Glisson (SWG) basis functions is proposed to analyze electromagnetic scattering from inhomogeneous dielectric objects. For this proposed scheme, almost no half-SWG basis functions are needed for the elements separating nonconformal meshes, while these half-SWG basis functions are indispensable for the conventional DGVIE-SWG method. This is realized by applying the divergence-free condition of the electric displacement vector explicitly for nonconformal meshes separating neighboring subdomains of an inhomogeneous dielectric body. Therefore, the number of unknowns of the conventional DGVIE method can be further reduced. As a result, the memory of the proposed DGVIE method is only about half of the conventional one for inhomogeneous dielectric problems. Meanwhile, the total solution time has been reduced by the use of the proposed scheme. Particularly, the proposed DGVIE-SWG method is efficient in memory usage not only for inhomogeneous dielectric cases with high contrast ratio but also for cases with relatively low contrast ratio.

4.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(6): 942-948, 2023 Jun 10.
Artigo em Chinês | MEDLINE | ID: mdl-37380417

RESUMO

Objective: To grasp the epidemiological characteristics of influenza outbreaks in Guangdong Province by analyzing the outbreaks of influenza-like cases reported in Guangdong Province from January 2015 to the end of August 2022. Methods: In response to the outbreak of epidemics in Guangdong Province from 2015 to 2022, information on on-site epidemic control was collected, and epidemiological analysis was conducted to describe the characteristics of the epidemics. The factors that influence the intensity and duration of the outbreak were determined through a logistic regression model. Results: A total of 1 901 influenza outbreaks were reported in Guangdong Province, with an overall incidence of 2.05%. Most outbreak reports occurred from November to January of the following year (50.24%, 955/1 901) and from April to June (29.88%, 568/1 901). A total of 59.23% (1 126/1 901) of the outbreaks were reported in the Pearl River Delta region, and primary and secondary schools were the main places where outbreaks occurred (88.01%, 1 673/1 901). Outbreaks with 10-29 cases were the most common (66.18%, 1 258/1 901), and most outbreaks lasted less than seven days (50.93%,906/1 779). The size of the outbreak was related to the nursery school (aOR=0.38, 95%CI:0.15-0.93), the Pearl River Delta region (aOR=0.60, 95%CI:0.44-0.83), the time interval between the onset of the first case and the time of report (>7 days compared with ≤3 days: aOR=3.01, 95%CI:1.84-4.90), the influenza A(H1N1) (aOR=2.02, 95%CI:1.15-3.55) and the influenza B (Yamagata) (aOR=2.94, 95%CI: 1.50-5.76). The duration of outbreaks was related to school closures (aOR=0.65, 95%CI: 0.47-0.89), the Pearl River Delta region (aOR=0.65, 95%CI: 0.50-0.83) and the time interval between the onset of the first case and the time of report (>7 days compared with ≤3 days: aOR=13.33, 95%CI: 8.80-20.19; 4-7 days compared with ≤3 days: aOR=2.56, 95%CI: 1.81-3.61). Conclusions: An influenza outbreak in Guangdong Province exhibits two peaks, one in the winter and spring seasons and the other in the summer. Primary and secondary schools are high-risk areas, and early reporting of outbreaks is critical for controlling influenza outbreaks in schools. Furthermore, comprehensive measures should be taken to prevent the spread of the epidemic.


Assuntos
Epidemias , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Humanos , Influenza Humana/epidemiologia , Surtos de Doenças , China/epidemiologia
5.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(6): 954-959, 2023 Jun 10.
Artigo em Chinês | MEDLINE | ID: mdl-37380419

RESUMO

Objective: To explore the impact of health management measures for entry personnel (entry management measures) against COVID-19 on the epidemiological characteristics of imported Dengue fever in Guangdong Province from 2020 to 2022. Methods: Data of imported Dengue fever from January 1, 2016 to August 31, 2022, mosquito density surveillance from 2016 to 2021, and international airline passengers and Dengue fever annual reported cases from 2011 to 2021 in Guangdong were collected. Comparative analysis was conducted to explore changes in the epidemic characteristics of imported Dengue fever before the implementation of entry management measures (from January 1, 2016 to March 20, 2020) and after the implementation (from March 21, 2020 to August 31, 2022). Results: From March 21, 2020, to August 31, 2022, a total of 52 cases of imported Dengue fever cases were reported, with an imported risk intensity of 0.12, which were lower than those before implementation of entry management measures (1 828, 5.29). No significant differences were found in the characteristics of imported cases before and after implementation of entry management measures, including seasonality, sex, age, career, and imported countries (all P>0.05). 59.62% (31/52) of cases were found at the centralized isolation sites and 38.46% (20/52) at the entry ports. However, before implementation of entry management measures, 95.08% (1 738/1 828) of cases were found in hospitals. Among 51 cases who had provided entry dates, 82.35% (42/51) and 98.04% (50/51) of cases were found within seven days and fourteen days after entry, slightly higher than before implementation [(72.69%(362/498) and 97.59% (486/498)]. There was significant difference between the monthly mean values of Aedes mosquito larval density (Bretto index) from 2020 to 2021 and those from 2016 to 2019 (Z=2.83, P=0.005). There is a strong positive correlation between the annual international airline passengers volume in Guangdong from 2011 to 2021 and the annual imported Dengue fever cases (r=0.94, P<0.001), and a positive correlation also existed between the international passenger volume and the annual indigenous Dengue fever cases (r=0.72, P=0.013). Conclusions: In Guangdong, the entry management measures of centralized isolation for fourteen days after entry from abroad had been implemented, and most imported Dengue fever cases were found within fourteen days after entry. The risk of local transmission caused by imported cases has reduced significantly.


Assuntos
Aedes , COVID-19 , Dengue , Epidemias , Animais , Humanos , China/epidemiologia , Dengue/epidemiologia
6.
Lett Appl Microbiol ; 75(4): 1055-1062, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35771175

RESUMO

A pectin lyase gene pnlzj5b from Aspergillus niger ZJ5 was identified and overexpressed successfully in Pichia pastoris. Recombinant PNLZJ5B exhibited high activity towards citrus pectin (150 U ml-1 ). Through further codon optimization, the expression efficiency of PNLZJ5B in P. pastoris increased to 3·5-fold (532/150 U ml-1 ). PNLZJ5B was purified by ultrafiltration, anion exchange and gel chromatography. It showed optimal activity and good stability at 58°C and pH 4·5. PNLZJ5B activity improved with increasing degrees of methyl esterification of pectin. The Km and Vmax values were 0·81 mg ml-1 and 372·8 µmol min-1 mg-1 , respectively. In addition, PNLZJ5B effectively decreased the viscosity of apple juice. Compared with commercial pectin lyase, PNLZJ5B obtained a higher juice volume. These favourable enzymatic properties of PNLZJ5B show potential utility in juice-processing applications and other food-related fields.


Assuntos
Aspergillus niger , Pichia , Aspergillus niger/genética , Concentração de Íons de Hidrogênio , Pectinas/metabolismo , Pichia/genética , Pichia/metabolismo , Polissacarídeo-Liases , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
7.
Zhonghua Liu Xing Bing Xue Za Zhi ; 43(5): 655-662, 2022 May 10.
Artigo em Chinês | MEDLINE | ID: mdl-35589568

RESUMO

2019-nCoV Omicron (B.1.1.529) variant, which has brought new challenges to the prevention and control of COVID-19 pandemic, has the characteristics of stronger transmissibility and more rapid transmission and more significant immune evasion. It took only two months to become a predominant strain worldwide after its identification in South Africa in November 2021. Local epidemics caused by Omicron variant have been reported in several provinces in China. However, the epidemiological characteristics of highly mutated Omicron variant remain unclear. This article summarizes the progress in the research of functional mutations, transmissibility, virulence, immune evasion and cross-reactive immune responses of Omicron variant, to provide references for the effective prevention and control of COVID-19 pandemic caused by Omicron variant.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Mutação , Pandemias
8.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(4): 474-478, 2022 Apr 06.
Artigo em Chinês | MEDLINE | ID: mdl-35488546

RESUMO

Objective: To analyze the course of disease and epidemiological parameters of COVID-19 and provide evidence for making prevention and control strategies. Methods: To display the distribution of course of disease of the infectors who had close contacts with COVID-19 cases from January 1 to March 15, 2020 in Guangdong Provincial, the models of Lognormal, Weibull and gamma distribution were applied. A descriptive analysis was conducted on the basic characteristics and epidemiological parameters of course of disease. Results: In total, 515 of 11 580 close contacts were infected, with an attack rate about 4.4%, including 449 confirmed cases and 66 asymptomatic cases. Lognormal distribution was fitting best for latent period, incubation period, pre-symptomatic infection period of confirmed cases and infection period of asymptomatic cases; Gamma distribution was fitting best for infectious period and clinical symptom period of confirmed cases; Weibull distribution was fitting best for latent period of asymptomatic cases. The latent period, incubation period, pre-symptomatic infection period, infectious period and clinical symptoms period of confirmed cases were 4.50 (95%CI:3.86-5.13) days, 5.12 (95%CI:4.63-5.62) days, 0.87 (95%CI:0.67-1.07) days, 11.89 (95%CI:9.81-13.98) days and 22.00 (95%CI:21.24-22.77) days, respectively. The latent period and infectious period of asymptomatic cases were 8.88 (95%CI:6.89-10.86) days and 6.18 (95%CI:1.89-10.47) days, respectively. Conclusion: The estimated course of COVID-19 and related epidemiological parameters are similar to the existing data.


Assuntos
COVID-19 , Busca de Comunicante , Estudos de Coortes , Humanos , Incidência , Estudos Prospectivos
9.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(1): 49-55, 2022 Jan 06.
Artigo em Chinês | MEDLINE | ID: mdl-35092991

RESUMO

Objective: To analyze the epidemiological characteristics and influencing factors of COVID-19 confirmed cases with viral nucleic acid re-positive in anal and/or throat swabs after discharge during the domestic imported epidemic stage in Guangdong Province in early 2020. Methods: The COVID-19 confirmed cases with the onset time before March 1, 2020 in Guangdong Province were collected to analyze the demographic data, epidemiological characteristics, and specimen collection and testing data after discharge. Logistic regression model was used for influencing factors analysis of re-positive cases. Results: A total of 1 286 COVID-19 confirmed cases were included, the M(Q1,Q3) of age was 44(32,58)years, 617 cases were male, 224 cases were re-positive in anal and/or throat swabs with the re-positive rate 17.42%. The M(Q1,Q3) of age of re-positive cases was 35(23, 50) years, which was younger than that of re-negative cases age was those 46(33, 59) years (P<0.001). With the increase of age, re-positive rate decreased (χ2trend=52.73, P<0.001). 85.27% (191/224) of re-positive cases were found in 14 d after discharge, the duration time of re-positive status was 13(7, 24) d, and 81.69% (183/224) of re-positive cases were re-tested negative in 28 d after re-positive date. No fever and other symptoms had been observed among re-positive cases during the whole follow-up. No secondary infectious cases had been found among close contacts after 14 d of centralized isolation and sampling screening. Univariate logistic regression model analysis revealed that the influencing factors of the re-positive cases included age, occupation, clusters, clinical types, and admission time. Multivariate logistic regression model analysis revealed that age was an independent risk factor. Conclusions: SARS-CoV-2 viral nucleic acid re-positive is found in COVID-19 confirmed cases after discharge in Guangdong Province. Most re-positive cases are confirmed among 14 d after discharge and re-test to negative among 28 d after re-positive date. Age is an risk factor for re-positive cases after discharge.


Assuntos
COVID-19 , Epidemias , Ácidos Nucleicos , China/epidemiologia , Humanos , Masculino , SARS-CoV-2
10.
J Opt Soc Am A Opt Image Sci Vis ; 38(7): 1015-1023, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34263757

RESUMO

In this paper, electromagnetic scattering from dielectric objects with negative permittivity is solved by the volume integral equation (VIE)-hierarchical matrix (H-matrix)-based fast direct solver. To improve solution efficiency, a coarsening algorithm for the H-matrix is used, and the key parameter for the admissible condition is optimized through numerical experiments. Finally, the discontinuous Galerkin (DG) VIE (DGVIE) method is developed for the fast direct solver. It is shown that scattering from inhomogeneous dielectric objects with negative permittivity and with multiscale structure can be analyzed efficiently by the DGVIE-H-matrix-based fast direct solver.

11.
Carbon Balance Manag ; 16(1): 4, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33515367

RESUMO

BACKGROUND: Networks of tower-based CO2 mole fraction sensors have been deployed by various groups in and around cities across the world to quantify anthropogenic CO2 emissions from metropolitan areas. A critical aspect in these approaches is the separation of atmospheric signatures from distant sources and sinks (i.e., the background) from local emissions and biogenic fluxes. We examined CO2 enhancements compared to forested and agricultural background towers in Indianapolis, Indiana, USA, as a function of season and compared them to modeled results, as a part of the Indianapolis Flux (INFLUX) project. RESULTS: At the INFLUX urban tower sites, daytime growing season enhancement on a monthly timescale was up to 4.3-6.5 ppm, 2.6 times as large as those in the dormant season, on average. The enhancement differed significantly depending on choice of background and time of year, being 2.8 ppm higher in June and 1.8 ppm lower in August using a forested background tower compared to an agricultural background tower. A prediction based on land cover and observed CO2 fluxes showed that differences in phenology and drawdown intensities drove measured differences in enhancements. Forward modelled CO2 enhancements using fossil fuel and biogenic fluxes indicated growing season model-data mismatch of 1.1 ± 1.7 ppm for the agricultural background and 2.1 ± 0.5 ppm for the forested background, corresponding to 25-29% of the modelled CO2 enhancements. The model-data total CO2 mismatch during the dormant season was low, - 0.1 ± 0.5 ppm. CONCLUSIONS: Because growing season biogenic fluxes at the background towers are large, the urban enhancements must be disentangled from the biogenic signal, and growing season increases in CO2 enhancement could be misinterpreted as increased anthropogenic fluxes if the background ecosystem CO2 drawdown is not considered. The magnitude and timing of enhancements depend on the land cover type and net fluxes surrounding each background tower, so a simple box model is not appropriate for interpretation of these data. Quantification of the seasonality and magnitude of the biological fluxes in the study region using high-resolution and detailed biogenic models is necessary for the interpretation of tower-based urban CO2 networks for cities with significant vegetation.

12.
QJM ; 113(11): 799-805, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32840579

RESUMO

BACKGROUND: Patients on dialysis were susceptible to coronavirus disease 2019 (COVID-19) and were prone to severe clinical characteristics after infection; acute kidney injury was related to mortality in COVID-19 cases. Limited is known about the characteristics of COVID-19 patients with end-stage renal disease not requiring renal replacement therapy (RRT). AIM: Evaluate clinical characteristics, course and outcomes of COVID-19 patients with chronic kidney disease (CKD) who did not require RRT and those on dialysis. DESIGN: A two-center retrospective study. METHODS: A total of 836 adult patients with COVID-19 (24 CKD not on dialysis; 15 dialysis-dependent CKD) were included. The study includes no patients with renal transplantation. Risk factors were explored. RESULTS: CKD not requiring RRT is an independent risk factor for in-hospital death [adjusted odds ratio (aOR) 7.35 (95% CI 2.41-22.44)] and poor prognosis [aOR 3.01 (95% CI 1.23-7.33)]. Compared with COVID-19 cases without CKD, those with CKD not requiring RRT showed similar percentage of initial moderate cases (75.00% vs. 73.65%) but higher incidence of in-hospital neutrophilia (50.00% vs. 27.30%) or death (50.00% vs. 9.03%). The odds ratio of dialysis associated to mortality in CKD patients was 2.00 (95% CI 0.52-7.63), suggesting COVID-19 patients with dialysis-dependent CKD were at greater risk of in-hospital death. For COVID-19 patients with CKD not requiring RRT, statins reduced the risk of neutrophilia [OR 0.10 (95% CI 0.01-0.69)] while diuretics increased the risk of neutrophilia [OR 15.4 (95% CI 1.47-160.97)], although both showed no association to mortality. CONCLUSION: COVID-19 patients with CKD presented high incidence of neutrophilia, poor prognosis and in-hospital death, with dialysis patients being more vulnerable.


Assuntos
Infecções por Coronavirus/epidemiologia , Hospitalização/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Diálise Renal/métodos , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/terapia , Síndrome Respiratória Aguda Grave/epidemiologia , Adulto , Fatores Etários , Idoso , COVID-19 , Causas de Morte , China , Estudos de Coortes , Infecções por Coronavirus/diagnóstico , Feminino , Mortalidade Hospitalar/tendências , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Pandemias , Pneumonia Viral/diagnóstico , Prognóstico , Insuficiência Renal Crônica/diagnóstico , Estudos Retrospectivos , Medição de Risco , Síndrome Respiratória Aguda Grave/diagnóstico , Síndrome Respiratória Aguda Grave/terapia , Índice de Gravidade de Doença , Fatores Sexuais , Resultado do Tratamento
13.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(7): 720-725, 2020 Jul 06.
Artigo em Chinês | MEDLINE | ID: mdl-32842292

RESUMO

Objective: Analysis of clustering characteristics of coronavirus disease 2019 (COVID-19) in Guangdong Province. Methods: The COVID-19 cases in Guangdong Province onset from January 1 to February 29, 2020 were collected from Chinese information system for disease control and prevention and Emergency Public Reporting System. Obtain the epidemiological survey data of the cluster epidemic situation, and clarify the scale of cluster epidemic situation, the characteristics of the index cases, family and non-family subsequent cases. Calculate serial interval according to the onset time of the index cases and subsequent cases, secondary attack rate based on the close contacts tracking results, the characteristics of different cases in the clustered epidemic were compared. Results: A total of 283 cluster were collected, including 633 index cases, 239 subsequent cases. Families are mainly clustered, the total number involved in each cluster is in the range of 2-27, M (P25, P75) are 2.0 (2.0, 4.0). During January 15 to February 29, the secondary attack rate is 2.86% (239/8 363) in Guangdong Province, the family secondary attack rate was 4.84% (276/3 697), and the non-family secondary attack rate was 1.32% (61/4 632). According to the reporting trend of the number of cases in Guangdong Province, it can be divided into four stages, the rising stage, the high platform stage, the descending stage and the low level fluctuation period. The secondary attack rate of the four stages were 3.5% (140/3 987), 2.3% (55/2 399), 2.6% (37/1 435), 1.3% (7/542), respectively. The difference was statistically significant (P=0.003). Conclusion: COVID-19 cluster mainly occurs in families in Guangdong Province. The scale of the clustered epidemic was small; the serial interval was short; and the overall secondary attack rate was low.


Assuntos
Infecções por Coronavirus/epidemiologia , Epidemias , Pneumonia Viral/epidemiologia , COVID-19 , China/epidemiologia , Análise por Conglomerados , Humanos , Pandemias
14.
Clin Microbiol Infect ; 26(10): 1400-1405, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32622952

RESUMO

OBJECTIVE: Most cases of coronavirus disease 2019 (COVID-19) are identified as moderate, which is defined as having a fever or dry cough and lung imaging with ground-glass opacities. The risk factors and predictors of prognosis in such cohorts remain uncertain. METHODS: All adults with COVID-19 of moderate severity diagnosed using quantitative RT-PCR and hospitalized at the Central Hospital of Wuhan, China, from 1 January to 20 March 2020 were enrolled in this retrospective study. The main outcomes were progression from moderate to severe or critical condition or death. RESULTS: Among the 456 enrolled patients with moderate COVID-19, 251/456 (55.0%) had poor prognosis. Multivariate logistic regression analysis identified higher neutrophil count: lymphocyte count ratio (NLR) on admission (OR 1.032, 95% CI 1.042-1.230, p 0.004) and higher C-reactive protein (CRP) on admission (OR 3.017, 95% CI 1.941-4.690, p < 0.001) were associated with increased OR of poor prognosis. The area under the receiver operating characteristic curve (AUC) for NLR and CRP in predicting progression to critical condition was 0.77 (95% CI 0.694-0.846, p < 0.001) and 0.84 (95% CI 0.780-0.905, p < 0.001), with a cut-off value of 2.79 and 25.95 mg/L, respectively. The AUC of NLR and CRP in predicting death was 0.81 (95% CI 0.732-0.878, p < 0.001) and 0.89 (95% CI 0.825-0.946, p < 0.001), with a cut-off value of 3.19 and 33.4 mg/L, respectively. CONCLUSIONS: Higher levels of NLR and CRP at admission were associated with poor prognosis of individuals with moderate COVID-19. NLR and CRP were good predictors of progression to critical condition and death.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/patologia , Linfócitos/patologia , Pneumonia Viral/diagnóstico , Pneumonia Viral/patologia , Adulto , Antibacterianos/uso terapêutico , Antivirais/uso terapêutico , Área Sob a Curva , Betacoronavirus/efeitos dos fármacos , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/mortalidade , Progressão da Doença , Feminino , Humanos , Contagem de Linfócitos , Linfócitos/virologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/mortalidade , Prognóstico , Curva ROC , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2 , Índice de Gravidade de Doença , Análise de Sobrevida
15.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(12): 1999-2004, 2020 Dec 10.
Artigo em Chinês | MEDLINE | ID: mdl-32340095

RESUMO

Objective: To analyze the clinical courses and outcomes of COVID-19 cases and the influencing factors in Guangdong province and provide basis for the formulation or adjustment of medical care and epidemic control strategy for COVID-19. Methods: We collected demographic data, medical histories, clinical courses and outcomes of 1 350 COVID-19 patients reported in Guangdong as of 4 March 2020 via epidemiological investigation and process tracking. Disease severity and clinical course characteristics of the patients and influencing factors of severe illness were analyzed in our study. Results: Among 1 350 cases of COVID-19 cases in Guangdong, 72 (5.3%) and 1 049 (77.7%) were mild and ordinary cases, 164 (12.1%) were severe cases, 58 (4.3%) were critical cases and 7 (0.5%) were fatal. The median duration of illness were 23 days (P(25), P(75): 18, 31 days) and the median length of hospitalization were 20 days (P(25), P(75): 15,27 days). For severe cases, the median time of showing severe manifestations was on the 12(th) day after onset (P(25), P(75): 9(th) to 15(th) days), and the median time of severe manifestation lasted for 8 days (P(25), P(75): 4, 14 days). Among 1 066 discharged/fetal cases, 36.4% (36/99) and 1.0% (1/99) of the mild cases developed to ordinary cases and severe cases respectively after admission; and 5.2% (50/968) and 0.6% (6/968) of the ordinary cases developed to severe cases, and critical cases respectively after admission. In severe cases, 11.4% developed to critical cases (10/88). The influencing factors for severe illness or worse included male (aHR=1.87, 95%CI: 1.43-2.46), older age (aHR=1.67, 95%CI: 1.51-1.85), seeking medical care on day 2-3 after onset (aHR=1.73, 95%CI: 1.20-2.50) pre-existing diabetes (aHR=1.75, 95%CI: 1.12-2.73) and hypertension (aHR=1.49, 95%CI: 1.06-2.09). Conclusions: The course of illness and length of hospitalization of COVID-19 cases were generally long and associated with severity of disease clinical outcomes. The severe cases were mainly occurred in populations at high risk. In the epidemic period, classified management of COVID-19 cases should be promoted according to needs for control and prevention of isolation and treatment for the purpose of rational allocation of medical resources.


Assuntos
COVID-19 , Idoso , COVID-19/epidemiologia , China/epidemiologia , Hospitalização , Humanos , Masculino , Alta do Paciente , SARS-CoV-2
16.
Phys Rev Lett ; 124(4): 044802, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32058730

RESUMO

Plasma wakefields can enable very high accelerating gradients for frontier high energy particle accelerators, in excess of 10 GeV/m. To overcome limits on single stage acceleration, specially shaped drive beams can be used in both linear and nonlinear plasma wakefield accelerators (PWFA), to increase the transformer ratio, implying that the drive beam deceleration is minimized relative to acceleration obtained in the wake. In this Letter, we report the results of a nonlinear PWFA, high transformer ratio experiment using high-charge, longitudinally asymmetric drive beams in a plasma cell. An emittance exchange process is used to generate variable drive current profiles, in conjunction with a long (multiple plasma wavelength) witness beam. The witness beam is energy modulated by the wakefield, yielding a response that contains detailed spectral information in a single-shot measurement. Using these methods, we generate a variety of beam profiles and characterize the wakefields, directly observing transformer ratios up to R=7.8. Furthermore, a spectrally based reconstruction technique, validated by 3D particle-in-cell simulations, is introduced to obtain the drive beam current profile from the decelerating wake data.

17.
Eur Rev Med Pharmacol Sci ; 23(23): 10433-10442, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31841197

RESUMO

OBJECTIVE: Triple negative breast cancer (TNBC) is a subtype of breast cancer without the three markers, which has a poor prognosis than other types. Recently, studies have identified that microRNA-92b (miR-92b) acted as potential oncogene in tumor progression, however, the biological roles of miR-92b in TNBC remain unknown. The purpose of this study was to investigate the functions of miR-92b and verify its effect on the regulation of Gabra3 in TNBC. MATERIALS AND METHODS: Dual-Luciferase reporter assay was recruited to confirm whether miR-92b directly binds to the 3'-untranslated region (3'-UTR) of Gabra3 mRNA in TNBC. Transwell assay was employed to analyze the capacities of migration and invasion. Western blot was applied to evaluate the expression of the special proteins that including Gabra3, epithelial-mesenchymal transition (EMT) markers and GAPDH. RESULTS: We demonstrated that miR-92b was remarkably low expressed in TNBC tissues and cell lines, and particularly in inhibiting the migration, invasion and EMT of TNBC cells. On the contrary, Gabra3 was significantly overexpressed in TNBC tissues and cell lines in comparison with the corresponding paracancerous tissues and the normal breast epithelial cell line. The expression of miR-92b had a negative correlation with the expression of Gabra3 in TNBC tissues. Downregulation of Gabra3 could inhibit the migration, invasion and EMT of TNBC cells. MiR-92b mediated the expression of Gabra3 through directly binding to the 3'-UTR of Gabra3 mRNA. In addition, low expression of miR-92b or overexpression of Gabra3 predicted poor prognosis of TNBC patients. CONCLUSIONS: MiR-92b inhibited the migration and invasion-mediated EMT through directly targeting the 3'-UTR of Gabra3 mRNA in triple negative breast cancer. The newly identified miR-92b/Gabra3 axis may make it to be a new target for clinical diagnosis and treatment of TNBC.


Assuntos
Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Receptores de GABA-A/genética , Neoplasias de Mama Triplo Negativas/genética , Regiões 3' não Traduzidas/genética , Mama/patologia , Mama/cirurgia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Estimativa de Kaplan-Meier , Mastectomia , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Prognóstico , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/cirurgia
18.
J Biol Regul Homeost Agents ; 33(2): 321-330, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30972994

RESUMO

Nasopharyngeal carcinoma (NPC) is a malignant tumor with high invasive and metastatic properties. Dysregulation of miRNAs may contribute to disease progression by targeting disease-related genes. In this study we aimed to elucidate the role and function of aberrantly expressed miRNA in NPC tumorigenesis. We found that miR-1178-3p was highly expressed in NPC tissues. Overexpression of miR-1178-3p promoted the proliferation, migration and invasion of NPC cells in vitro. In contrast, knocking down endogenous miR-1178-3p by miRNA-specific inhibitor significantly suppressed the above phenotypes. Moreover, miR- 1178-3p was shown to negatively regulate serine/threonine-protein kinase 4 (STK4), an NPC-related tumor suppressor gene, in the post-transcriptional level. Furthermore, STK4 overexpression abolished miR-1178- 3p-induced cell proliferation, migration and invasion through STK4-mediated dephosphorylation of AKT. Our results indicate that miR-1178-3p acts as an oncomiRNA in NPC by suppressing STK4 expression, and inhibition of miR-1178-3p may become a therapeutic potential for NPC.


Assuntos
MicroRNAs/genética , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genética , Invasividade Neoplásica
20.
Eur Rev Med Pharmacol Sci ; 22(21): 7543-7550, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30468504

RESUMO

OBJECTIVE: To investigate whether CD31 could regulate paracetamol-induced liver injury, thereby providing a new direction for the prevention and treatment of drug-induced hepatitis. MATERIALS AND METHODS: Wild-type (WT) mice were treated with acetaminophen (APAP) (250 mg/kg) or isodose of phosphate-buffered saline (PBS). 1, 3, 6 and 12 h after the treatment, the messenger RNA (mRNA) and protein expression level of CD31 in the liver of mice were determined by Real-time reverse transcription polymerase chain reaction (RT-PCR) and Western blotting, respectively. Once CD31 was confirmed to be involved in APAP-induced liver injury, the acute liver injury model in WT mice and CD31 gene deficient (CD31-/-) mice induced by APAP was established. Serum samples were collected at 8 and 24 h after APAP injection (250 mg/kg), and the activity of serum alanine aminotransferase (ALT) was measured. The liver tissues of mice were isolated and analyzed by hematoxylin and eosin (HE) staining. Meanwhile, mononuclear cells (MNCs) were isolated from the liver tissues of mice. The number of infiltrating macrophages and neutrophils was detected by flow cytometry, and the activation level of these cells was analyzed. The expression levels of proinflammatory cytokines in liver tissues, such as TNF-α, IL-1ß, keratinocyte chemoattractant (KC), MCP-1 and IL-6, were determined by RT-PCR. The expression levels of cytokines in serum were detected by enzyme-linked immunosorbent assay (ELISA). Moreover, the protein expression levels of JNK, Caspase-3, and cytochrome P450 2E1 (CYP2E1) in liver tissues were detected by Western blotting. RESULTS: After APAP treatment, we found that WT mice were more sensitive to APAP-induced liver injury. The level of ALT in WT mice was significantly higher than that of CD31-/- mice, meanwhile, more necrotic or apoptotic cells were found in WT mice. Results also indicated that the expression levels of inflammatory cytokines, including KC, IL-1ß, MCP-1 and IL-6, were significantly higher in WT mice. Meanwhile, the number of infiltrating macrophages and neutrophils in the liver tissues of WT mice were much more than that of CD31-/- mice. CONCLUSIONS: APAP-treated CD31-/- mice exhibited less liver injury when compared with WT mice. We also confirmed that CD31 was greatly involved in APAP-induced inflammatory response by promoting hepatic inflammatory and cell apoptosis, which might provide a new strategy for the prevention and treatment of drug-induced hepatitis.


Assuntos
Acetaminofen/toxicidade , Apoptose/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Inflamação/induzido quimicamente , Fígado/patologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/fisiologia , Animais , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Citocinas/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA