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1.
Inorg Chem ; 59(17): 12842-12849, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32794400

RESUMO

Three novel Zr-substituted polyoxotungstate aggregates [H2N(CH3)2]7NaH2[Zr2Sb2O3(A-α-PW9O34)2]·16H2O (1), [H2N(CH3)2]6H12[ZrSb4(OH)O2(A-α-PW8O32)(A-α-PW9O34)]2·33H2O (2), and [H2N(CH3)2]4Na11.5H4.5[Zr4W8Sb4P5O49(OH)5(B-α-SbW9O33)2]·53H2O (3) have been made in hydrothermal reactions of the [B-α-SbW9O33]9- precursor with Zr4+ cations and PO43- anions in the presence of dimethylamine hydrochloride and sodium acetate buffer (pH = 4.8) and structurally characterized. Different pH values induce structural transformation from tungstoantimonate (TA) to tungstophosphate (TP). 1 is a di-Zr-substituted sandwich-type TP, the tetranuclear heterometallic [Zr2Sb2O3]8+ entity sandwiched by two [A-α-PW9O34]9- moieties. 2 is a double sandwich-type structure, which can be perceived as two equivalent sandwiched [Sb3(PW8O32)(PW9O34)]11- further sandwiching one [Sb2Zr2(OH)2O4]4+ core to form a novel large-size sandwich-type architecture. Different from 1 and 2, 3 is a tetra-Zr-substituted sandwiched configuration, in which two [B-α-SbW9O33]9- fragments sandwich a unique 21-core Sb-P-W-Zr oxo cluster ({Zr4W8Sb4P5}). Furthermore, the catalytic oxidation of aromatic thioethers by 3 as the heterogeneous catalyst has been investigated, showing high conversion and remarkable selectivity as well as excellent recyclability.

2.
Inorg Chem ; 59(9): 6131-6136, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32314581

RESUMO

A new nonanuclear heterometal five-layer sandwich silicotungstate [H2N(CH3)2]6H5NaK{[NaMn8O6(OAc)6][A-α-SiW9O34]2}·34H2O (1) has been made under hydrothermal reactions of MnCl2·4H2O, KMnO4, trivacant [A-α-SiW9O34]10- {SiW9} fragment, and [H2N(CH3)2]·Cl in NaOAc-HOAc buffer (pH = 4.8). The polyoxoanion of 1 is a sandwich architecture, in which the nonanuclear heterometal cluster [NaMn8O6(OAc)6]7+ made of two triangular pyramid clusters [Mn4O3(OAc)3]3+ {Mn4} via a hexacoordinate antitrigonal prism Na+ linkage is encapsulated by two trivacant fragments of {SiW9}. Furthermore, magnetic measurements of compound 1 reveal the existence of antiferromagnetic exchange interactions between the metal centers.

3.
N Engl J Med ; 369(21): 1981-90, 2013 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-24256377

RESUMO

BACKGROUND: The last case of infection with wild-type poliovirus indigenous to China was reported in 1994, and China was certified as a poliomyelitis-free region in 2000. In 2011, an outbreak of infection with imported wild-type poliovirus occurred in the province of Xinjiang. METHODS: We conducted an investigation to guide the response to the outbreak, performed sequence analysis of the poliovirus type 1 capsid protein VP1 to determine the source, and carried out serologic and coverage surveys to assess the risk of viral propagation. Surveillance for acute flaccid paralysis was intensified to enhance case ascertainment. RESULTS: Between July 3 and October 9, 2011, investigators identified 21 cases of infection with wild-type poliovirus and 23 clinically compatible cases in southern Xinjiang. Wild-type poliovirus type 1 was isolated from 14 of 673 contacts of patients with acute flaccid paralysis (2.1%) and from 13 of 491 healthy persons who were not in contact with affected persons (2.6%). Sequence analysis implicated an imported wild-type poliovirus that originated in Pakistan as the cause of the outbreak. A public health emergency was declared in Xinjiang after the outbreak was confirmed. Surveillance for acute flaccid paralysis was enhanced, with daily reporting from all public and private hospitals. Five rounds of vaccination with live, attenuated oral poliovirus vaccine (OPV) were conducted among children and adults, and 43 million doses of OPV were administered. Trivalent OPV was used in three rounds, and monovalent OPV type 1 was used in two rounds. The outbreak was stopped 1.5 months after laboratory confirmation of the index case. CONCLUSIONS: The 2011 outbreak in China showed that poliomyelitis-free countries remain at risk for outbreaks while the poliovirus circulates anywhere in the world. Global eradication of poliomyelitis will benefit all countries, even those that are currently free of poliomyelitis.


Assuntos
Surtos de Doenças , Poliomielite/epidemiologia , Vacina Antipólio Oral , Poliovirus/genética , Adolescente , Adulto , Distribuição por Idade , Proteínas do Capsídeo/genética , Criança , Pré-Escolar , China/epidemiologia , Surtos de Doenças/prevenção & controle , Feminino , Humanos , Incidência , Lactente , Masculino , Filogenia , Poliomielite/diagnóstico , Poliomielite/prevenção & controle , Poliomielite/transmissão , Poliovirus/isolamento & purificação , Vacina Antipólio Oral/administração & dosagem , Vigilância da População , Prática de Saúde Pública , Distribuição por Sexo
4.
N Engl J Med ; 364(7): 638-47, 2011 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-21288090

RESUMO

BACKGROUND: On September 21, 2009, China began administering vaccines, obtained from 10 different manufacturers, against 2009 pandemic influenza A (H1N1) virus infection in priority populations. We aimed to assess the safety of this vaccination program. METHODS: We designed a plan for passive surveillance for adverse events after immunization with the influenza A (H1N1) vaccine. Physicians or vaccination providers were required to report the numbers of vaccinees and all adverse events to their local Center for Disease Control and Prevention (CDC), which then reported the data to the Chinese CDC through the online National Immunization Information System's National Adverse Event Following Immunization Surveillance System. Data were collected through March 21, 2010, and were verified and analyzed by the Chinese CDC. RESULTS: A total of 89.6 million doses of vaccine were administered from September 21, 2009, through March 21, 2010, and 8067 vaccinees reported having an adverse event, for a rate of 90.0 per 1 million doses. The age-specific rates of adverse events ranged from 31.4 per 1 million doses among persons 60 years of age or older to 130.6 per 1 million doses among persons 9 years of age or younger, and the manufacturer-specific rates ranged from 4.6 to 185.4 per 1 million doses. A total of 6552 of the 8067 adverse events (81.2%; rate, 73.1 per 1 million doses) were verified as vaccine reactions; 1083 of the 8067 (13.4%; rate, 12.1 per 1 million doses) were rare and more serious (vs. common, minor events), most of which (1050) were allergic reactions. Eleven cases of the Guillain-Barré syndrome were reported, for a rate of 0.1 per 1 million doses, which is lower than the background rate in China. CONCLUSIONS: No pattern of adverse events that would be of concern was observed after the administration of influenza A (H1N1) vaccine, nor was there evidence of an increased risk of the Guillain-Barré syndrome.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza/efeitos adversos , Influenza Humana/prevenção & controle , Vigilância de Produtos Comercializados , Adolescente , Adulto , Criança , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Adulto Jovem
5.
Biomed Environ Sci ; 24(6): 624-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22365398

RESUMO

OBJECTIVE: To evaluate the effect of the aluminum hydroxide (Al-OH) adjuvant on the 2009 pandemic influenza A/H1N1 (pH1N1) vaccine. METHODS: In a multicenter, double-blind, randomized, placebo-controlled trial, participants received two doses of split-virion formulation containing 15 µg hemagglutinin antigen, with or without aluminum hydroxide (Al-OH). We classified the participants into six age categories (>61 years, 41-60 years, 19-40 years, 13-18 years, 8-12 years, and 3-7 years) and obtained four blood samples from each participant on days 0, 21, 35, and 42 following the first dose of immunization. We assessed vaccine immunogenicity by measuring the geometric mean titer (GMT) of hemagglutination inhibiting antibody. We used a two-level model to evaluate the fixed effect of aluminum Al-OH and other factors, accounting for repeated measures. RESULTS: The predictions of repeated measurement on GMTs of formulations with or without Al-OH, were 80.35 and 112.72, respectively. Al-OH significantly reduced immunogenicity after controlling for time post immunization, age-group and gender. CONCLUSION: The Al-OH adjuvant does not increase but actually reduces the immunogenicity of the split-virion pH1N1 vaccine.


Assuntos
Adjuvantes Farmacêuticos/química , Hidróxido de Alumínio/química , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/virologia , Adolescente , Adulto , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , China , Interpretação Estatística de Dados , Método Duplo-Cego , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/química , Influenza Humana/epidemiologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Pandemias , Adulto Jovem
6.
Biomed Environ Sci ; 34(5): 348-355, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34059171

RESUMO

OBJECTIVE: To examine increases in average height among Chinese children and adolescents. METHODS: The data were obtained from the China Health and Nutrition Survey conducted during the period 1989-2015. A stratified multistage cluster sampling method was utilized to select participants aged 2-22 years in each province. Linear regression was used to examine the effects of age, birth cohort, and survey period on height. RESULTS: A total of 15,227 males and 13,737 females were included in the final analysis. Age (A) showed a continuous effect on height. The average heights of the investigated groups increased continuously during the investigation period. By 2015, the average height of the overall group increased by 7.87 cm compared to the average height during the 1989 survey. Moreover, birth year (cohort, C) also had a stable effect on height. Using the height of individuals born in or before 1975 as a reference, the average height of each birth cohort increased in comparison to the previous birth cohort. CONCLUSIONS: The height of Chinese children and adolescents was affected by age, period, and cohort effects, and this effect is governed by certain rules. The age-period-cohort model can be used to analyze the trends of children's and adolescent's heights. The findings provide a scientific basis for the formulation of children's and adolescents' growth and development policies in China.


Assuntos
Desenvolvimento do Adolescente , Estatura , Desenvolvimento Infantil , Indicadores Básicos de Saúde , Adolescente , Saúde do Adolescente , Fatores Etários , Criança , Saúde da Criança , Pré-Escolar , China , Feminino , Inquéritos Epidemiológicos , Humanos , Modelos Lineares , Masculino , Fatores Sexuais , Adulto Jovem
7.
Dalton Trans ; 48(38): 14306-14311, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31469137

RESUMO

A novel octa-Mn-substituted silicotungstate (ST) [H2N(CH3)2]8H19Na4{[K(H2O)4WO4][SiMnW10O38]3}[SiMnW10O38]·27H2O (1) has been made by the hydrothermal reaction of the trivacant [A-α-SiW9O34]10- ({SiW9}) building block with Mn2+ and Mn7+ cations in the presence of dimethylamine hydrochloride and systematically characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD) and single crystal X-ray diffraction. 1 is a tetrameric cluster formed by a hexa-MnII substituted cyclic trimeric {[K(H2O)4WO4][SiMnW10O38]3} unit and a {SiMnW10O38} fragment via two W-O-MnIII linkers. Furthermore, its electrochemistry, thermal stability and magnetic properties have been studied.

8.
Pediatr Infect Dis J ; 35(12): e392-e398, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27626917

RESUMO

BACKGROUND: Rotavirus is the leading cause of severe diarrhea among young children worldwide. Rotavirus vaccines have demonstrated substantial benefits in many countries that have introduced vaccine nationally. In China, where rotavirus vaccines are not available through the national immunization program, it will be important to review relevant local and global information to determine the potential value of national introduction. Therefore, we reviewed evidence of rotavirus disease burden among Chinese children younger than 5 years to help inform rotavirus vaccine introduction decisions. METHODS: We reviewed scientific literature on rotavirus disease burden in China from 1994 through 2014 in China National Knowledge Infrastructure, Wanfang and PubMed. Studies were selected if they were conducted for periods of 12 month increments, had more than 100 patients enrolled and used an accepted diagnostic test. RESULTS: Overall, 45 reports were included and indicate that rotavirus causes ~40% and ~30% of diarrhea-related hospitalizations and outpatient visits, respectively, among children younger than 5 years in China. Over 50% of rotavirus-related hospitalizations occur by age 1 year; ~90% occur by age 2 years. Regarding circulating rotavirus strains in China, there has been natural, temporal variation, but the predominant local strains are the same as those that are globally dominant. CONCLUSIONS: These findings affirm that rotavirus is a major cause of childhood diarrheal disease in China and suggest that a vaccination program with doses given early in infancy has the potential to prevent the majority of the burden of severe rotavirus disease.


Assuntos
Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus , Rotavirus , Pré-Escolar , China/epidemiologia , Diarreia/epidemiologia , Diarreia/prevenção & controle , Diarreia/virologia , Humanos , Lactente , Recém-Nascido , Estudos Retrospectivos , Infecções por Rotavirus/virologia
9.
Zhongguo Yi Miao He Mian Yi ; 15(2): 119-22, 2009 Apr.
Artigo em Zh | MEDLINE | ID: mdl-20077655

RESUMO

OBJECTIVE: To analyse the incidence character of varicella in Shandong, Gansu and Hunan provinces in 2007. METHOD: One township of rural area and one community of urban area were selected from Shandong, Gansu and Hunan each province for sampling. 34578 children were sampled and 1213 clinical diagnostic cases were confirmed. RESULT: The incidence of 0-14 ys was 1836.72/100,000 and the estimated incidence of entire population was 357.95/100,000. The peak age of incidence was 5-9 age group children. CONCLUSION: The incidence of varicella in China was high and the incidence was different between areas or ages.


Assuntos
Varicela/epidemiologia , Adolescente , Distribuição por Idade , Varicela/virologia , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino
10.
Zhongguo Yi Miao He Mian Yi ; 15(2): 123-6, 2009 Apr.
Artigo em Zh | MEDLINE | ID: mdl-20077656

RESUMO

OBJECTIVE: To analyse the economic burden of outpatient with varicella in China in 2007. METHODS: In three provinces, the sample were places are stratified by economic condition in district, county and township level. 811 outpatient cases were sampled and analysized. RESULTS: The cost of outpatient was 493.66 RMB per case, including direct expenses 219.52 RMB and indirect expenses 274.14 RMB per case. The total cost of outpatient varicella in China was 2.3 billion RMB in 2007. CONCLUSIONS: The disease burden was heavy in China.


Assuntos
Varicela/economia , Custos de Cuidados de Saúde , Gastos em Saúde , Pacientes Ambulatoriais , Varicela/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Masculino
11.
Zhonghua Liu Xing Bing Xue Za Zhi ; 28(5): 433-6, 2007 May.
Artigo em Zh | MEDLINE | ID: mdl-17877168

RESUMO

OBJECTIVE: To investigate the immunity level of diphtheria antibody among children living in the areas where different coverage rates of 4-vaccines stratified by results of national immunization program (NIP) reviewed in 2004. METHODS: According to data from 4-vaccine coverage rates of NIP reviewed in 2004, 3 levels could be set. We randomly selected 2 counties at each level and then 10 villages from each county with 42 children involved who were born between 1992 and 2003. ELISA quantitative method was used to test IgG of diphtheria antitoxin. RESULTS: (1) The positive rate of diphtheria antitoxin was only 49.6% with the highest as 78.1% and lowest as 33.0%. There was a significant decreasing trend of this positive rate with the increase of age. The highest (61.2%) fell in the group that were born in 2003 and the lowest (37.6%) was seen among children born in 1992 to 1995. (2) Geometric mean concentrations (GMCs) was only 0.48 IU/ml with a trend of decrease when age was increasing. There was no GMCs peak seen in children who were at the age of boosting, as expected. (3) Positive rates of children born between 2001 and 2003 were lower than 62% while the diphtheria-pertussis-tetanus (DPT) vaccine coverage rates were all higher than 90%. (4) There was no significant difference of diphtheria antitoxin positive rates between children with eligible routine immunization (58.1%) and those were ineligible (59.6%). CONCLUSION: Other than some specific ones, children from most of the investigated counties had a low level of antibody against diphtheria. The coverage rate of DPT vaccine did not necessarily reflect the immunity against diphtheria, suggesting the increase of immunity against diphtheria an urgent task to be taken care of.


Assuntos
Anticorpos Antibacterianos/imunologia , Antitoxina Diftérica/imunologia , Vacina contra Difteria, Tétano e Coqueluche/imunologia , Difteria/imunologia , Difteria/prevenção & controle , Adolescente , Distribuição por Idade , Criança , Pré-Escolar , China , Feminino , Humanos , Masculino
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