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1.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(4): 673-676, 2023 Apr 10.
Artigo em Chinês | MEDLINE | ID: mdl-37147844

RESUMO

With the expansion of mpox virus infection from endemic to a global epidemic in 2022, the WHO declared that the mpox event constituted a Public Health Emergency of International Concern. Due to the high degree of gene sequence similarity among orthopox viruses and cross-reactive antibodies induced by orthoviruses, smallpox vaccination may affect the immune response induced by mpox virus infection. The analysis of the protective effects of smallpox vaccination against mpox virus infection will help define the focus of prevention and control. In this review, we clarify the protection of the smallpox vaccine against mpox virus infection by analyzing the correlation between smallpox vaccination, immune response status, and clinical data and providing evidence for the prevention, control, and strategies of mpox epidemics.


Assuntos
Mpox , Vacina Antivariólica , Varíola , Humanos , Varíola/prevenção & controle , Varíola/epidemiologia , Mpox/tratamento farmacológico , Vacina Antivariólica/uso terapêutico , Vacinação , Imunidade
2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(6): 861-863, 2022 Jun 06.
Artigo em Chinês | MEDLINE | ID: mdl-35785870

RESUMO

The COVID-19 continues to spread throughout the world, and local clusters and outbreaks related to overseas imports have occurred in many places in China. Vaccination against COVID-19 is one of the most effective tools to prevent disease, severe illness and death. For vaccines developed and used by China, it is particularly important for scientific and targeted prevention and control to study different outbreak scenarios, to conduct in-depth real-world research on SARS-CoV-2 variants, and to further promote vaccine development and technical reserves. This article commented the effectiveness of COVID-19 vaccine, and prospected the future research on vaccine efficacy, immunization strategy and vaccine development, which provided evidence for optimizing vaccination strategy.


Assuntos
COVID-19 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Pandemias/prevenção & controle , SARS-CoV-2 , Eficácia de Vacinas
3.
Bioresour Technol ; 146: 451-456, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23954717

RESUMO

A bench scale system integrated with a non-thermal plasma (NTP) and a biotricking filtration (BTF) unit for the treatment of gases containing dimethyl sulfide (DMS) was investigated. DMS removal efficiency in the integrated system was up to 96%. Bacterial communities in the BTF were assessed by PCR-DGGE, which play the dominant role in the biological processes of metabolism, sulfur oxidation, sulfate-reducing and carbon oxidation. The addition of ozone from NTP made microbial community in BTF more complicated and active for DMS removal. The NTP oxidize DMS to simple compounds such as methanol and carbonyl sulfide; the intermediate organic products and DMS are further oxidized to sulfate, carbon dioxide, water vapors by biological degradation. These results show that NTP-BTF is achievable and open new possibilities for applying the integrated with NTP and BTF to odour gas treatment.


Assuntos
Poluentes Atmosféricos , Ozônio , Gases em Plasma , Sulfetos/análise , Sulfetos/química , Biodegradação Ambiental , Reatores Biológicos , Carbono/química , Eletroforese em Gel de Gradiente Desnaturante , Desenho de Equipamento , Filtração , Gases , Metanol/química , Oxigênio/química , Reação em Cadeia da Polimerase , Sulfatos/química , Enxofre/química , Óxidos de Enxofre/química , Fatores de Tempo
4.
Mol Cell Biochem ; 355(1-2): 201-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21553261

RESUMO

During anoxia/reoxygenation (A/R) injury, intracellular chloride ion concentration ([Cl(-)](i)) homeostasis may play a role in maintaining the normal physiological function of cardiomyocytes. Various chloride transport systems could have influenced the concentration of chloride ion, but what kinds of chloride transport systems could play an important role in cardiomyocytes subjected to A/R injury and its mechanism are unknown. The aim of our study was to clarify the contributions of various chloride transport systems to anoxia/reoxygenation in rat neonatal cardiac myocytes and further to investigate the involved mechanisms. Oxidative stress and redox-sensitive transcription factor (NF-kappaB) activation are believed to play an important role in the A/R injury. To assess whether oxidative stress and NF-kappaB involve [Cl(-)](i) changes resulting in cardiomyocytes injury, the anoxia-reoxygenation (A/R) injury model was successfully established and administered with inhibitors of various chloride transport systems. Administration with Cl(-)-substitution and Cl(-)/HCO(3) (-) exchange inhibitor(SITS) has been shown to produce a protective effect against A/R injury by decreasing [Cl(-)](i) concentration, lipid peroxidation (malondialdehyde (MDA)) levels, and NF-kappaB activity, and by increasing antioxidant enzyme (glutathione peroxidase (GSHPx), superoxide dismutase (SOD), and catalase(CAT)) activity. However, inhibitors for the Cl(-)-channel (9-AC) and Na(+)-K(+)-2Cl(-) co-transporter (bumetanide) had no effects. Our results indicate that Cl(-)/HCO(3) (-) exchange system plays an important role in the cardiocyte A/R injury by influencing [Cl(-)](i) concentration. The protective effects of SITS and Cl(-)-substitution on cardiomyocytes may be due to the attenuation of oxidative stress and inhibition of NF-kappaB activation.


Assuntos
Cloretos/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo , Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-dissulfônico/farmacologia , Animais , Antracenos/farmacologia , Apoptose , Bumetanida/farmacologia , Catalase/metabolismo , Hipóxia Celular , Sobrevivência Celular , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/metabolismo , Antiportadores de Cloreto-Bicarbonato/metabolismo , Produtos Fermentados do Leite , Ensaios Enzimáticos , Glutationa Peroxidase/metabolismo , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos , Masculino , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/patologia , Oxigênio/metabolismo , Cultura Primária de Células , Transporte Proteico , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Inibidores de Simportadores de Cloreto de Sódio e Potássio/farmacologia , Simportadores de Cloreto de Sódio-Potássio/metabolismo , Superóxido Dismutase/metabolismo
5.
J Phys Chem B ; 115(23): 7515-23, 2011 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-21608974

RESUMO

The assembly of nanocomplexes from bioactive peptides, namely, caseinophosphopeptides (CPPs) and chitosan (CS), at physiological conditions and various CS/CPP mass ratios has been systematically studied using a combination of liquid chromatography-tandem mass spectrometry (LC-MS/MS), turbidimetric titration, dynamic light scattering (DLS), electrophoretic mobility (ζ-potential) measurements, transmission electron microscopy (TEM), and fluorescence spectroscopy. Peptides incorporated with CS forming nanoparticles were prepared and identified using LC-MS/MS. They were characterized by different amounts of clusters of phosphorylated seryl residues. At low salt concentrations, an increase in CS/CPP mass ratio shifted the critical pH(φ1) value, which was designated as the formation of CS/CPP nanocomplexes, as well as pH(max), which represents the neutralization of positive and negative charges at higher pH values. The sizes, charges, morphologies, binding mechanisms, and binding constants of the bioactive peptide-chitosan nanocomplexes were analyzed, and our results suggest that three processes are involved in nanocomplex formation: First, negatively charged CPPs absorb to positively charged CS molecular chains to form intrapolymer nanocomplexes saturated with CPPs (CPPNPs). Subsequently, the negatively charged CPPNPs are bridged by the addition of positively charged CS, resulting in the formation of nearly neutral associative biopolymer complexes. Finally, further addition of excess chitosan breaks down the bridges of associative complexes and causes the formation of positively charged isolated spherical nanocomplexes. The binding between the peptides and CS is mainly driven by electrostatic interactions with a binding constant of K(cs) = 4.6 × 10(4) M(-1). Phosphorylated groups and other negatively charged amino acids, such as aspartic acid (Asp) and glutamic acid (Glu), in the CPPs might be the dominant sites for interaction with -NH(3)(+) groups on the CS molecular chains.


Assuntos
Quitosana/síntese química , Nanopartículas/química , Peptídeos/síntese química , Sequência de Aminoácidos , Quitosana/química , Cromatografia Gasosa-Espectrometria de Massas , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Peso Molecular , Tamanho da Partícula , Peptídeos/química
6.
Infection ; 36(2): 153-7, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18231717

RESUMO

BACKGROUND: This study aimed to examine public knowledge, attitudes and behaviors regarding antibiotic use in the community of Hong Kong. METHODS: A cross-sectional phone survey was conducted in 2006 on people aged 18 or older who were uninstitutionalized Hong Kong residents regarding antibiotic use for upper respiratory tract infections (URTIs). RESULTS: A total of 1,002 respondents participated in the survey and 77%, 72% and 85% of the respondents had adequate knowledge, appropriate attitude/belief and behavior on antibiotic use, respectively. Some respondents (26%) believed that antibiotic was needed for symptoms of URTIs if they felt sick enough to seek medical care and 8% would share antibiotic with family members. Eighty-nine (9%) respondents had acquired antibiotic without a prescription. During the most recent episode of URTI, 78% had completed the antibiotic treatment course. Stepwise multiple logistic showed that higher education level and family income were associated with adequate patient knowledge. Male gender was a predictor of poor behavior on antibiotic use. Appropriate belief was associated with tertiary level of education or above. CONCLUSIONS: Over 70% of the present cohort showed adequate knowledge, appropriate attitudes/beliefs and behavior on antibiotic use. Despite a small percent (8%-9%) of respondents reportedly shared and/or self-prescribed antibiotics, this would translate into the practice of half a million people in Hong Kong. Public education programmes should therefore be developed, targeting specific areas of misconceptions, misuse of antibiotic and vulnerable groups at risk of improper use of antibiotics.


Assuntos
Antibacterianos/uso terapêutico , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos Epidemiológicos , Infecções Respiratórias/tratamento farmacológico , Adulto , Estudos Transversais , Feminino , Hong Kong , Humanos , Masculino , Telefone
7.
Langmuir ; 21(7): 2737-42, 2005 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-15779942

RESUMO

Small-angle neutron scattering was used to characterize the solution behavior of charged carboxylic acid terminated "cascade" dendrimers (Z-Cascade/methane [4]/3-oxo-6-oxa-2-azaheptylidyne/3-oxo-2-azaheptylidyne/propanoic acids) of third (G3) and fifth (G5) generations as a function of dendrimer concentration, pH, and ionic strength. An increase in dendrimer concentration leads to a single broad peak in the scattering profile arising from interdendrimer interaction. The dissociation of terminal carboxylate groups also gives rise to an interdendrimer interaction peak, which could be suppressed by the addition of excess salt. The results of contrast matching measurements indicate the accumulation of an excess concentration of tetramethylammonium counterions around the surface of these highly charged particles, and the thickness of these counterions lies somewhere between 4 and 6 A. This conclusion is consistent with our previous potentiometric titration (Zhang, H.; et al. J. Phys. Chem. B 1997, 101, 3494) and capillary electrophoresis (Huang, Q. R.; et al. J. Phys. Chem. B 2000, 104, 898) data.

8.
Ann Hum Genet ; 67(Pt 3): 216-27, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12914574

RESUMO

Bone mineral density (BMD) is an important risk factor for osteoporosis and has strong genetic determination. While average BMD differs among major ethnic groups, several important candidate genes have been shown to underlie BMD variation within populations of the same ethnicity. To investigate whether important candidate genes may contribute to ethnic differences in BMD, we studied the degree of genetic differentiation among several important candidate genes between two major ethnic groups: Caucasians and Chinese. The genetic variability of these two populations (1131 randomly selected individuals) was studied at six restriction sites exhibiting polymorphisms of five important candidate genes for BMD: the BsaHI polymorphism of the calcium-sensing receptor (CASR) gene, the SacI polymorphism of the alpha2HS-glycoprotein (AHSG) gene, the PvuII and XbaI polymorphisms of the estrogen receptor alpha (ESR1) gene, the ApaI polymorphism of the vitamin D receptor (VDR) gene, and the BstBI polymorphism of the parathyroid hormone (PTH) gene. The two ethnic groups showed significant allelic and genotypic differentiation of all the polymorphisms studied. The mean FST was 0.103, which significantly differed from zero (P < 0.01). The Chinese population had lower mean heterozygosity (0.331) than the Caucasian one (0.444); the CASR-BsaHI and PTH-BstBI polymorphisms contributed most significantly to this difference. Analysis of the intra- and inter-population variability suggests that various types of natural selection may affect the observed patterns of variation at some loci. If some of the candidate genes we studied indeed underlie variation in BMD, their population differentiation revealed here between ethnic groups may contribute to understanding ethnic difference in BMD.


Assuntos
Povo Asiático/genética , Densidade Óssea/genética , População Branca/genética , Povo Asiático/etnologia , Feminino , Frequência do Gene , Humanos , Endogamia , Masculino , Osteoporose , Polimorfismo Genético , Fatores Sexuais , População Branca/etnologia
9.
Osteoporos Int ; 12(8): 699-705, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11580084

RESUMO

Patients with low bone mineral density (BMD) have a high risk of future fractures, and should be actively considered for treatment to reduce their risk. However, BMD measurements are not widely available in some communities, because of cost and lack of equipment. Simple questionnaires have been designed to help target high-risk women for BMD measurements, thereby avoiding the cost of measuring women at low risk. However, such tools have previously focused on evaluation of non-Asian women. We collected information about numerous risk factors from postmenopausal Asian women in eight countries in Asia using questionnaires, and evaluated the ability of these risk factors to identify women with osteoporosis as defined by femoral neck BMD T-scores < or =-2.5. Multiple variable regression analysis and item reduction yielded a final tool based on only age and body weight. This risk index had a sensitivity of 91% and specificity of 45%, with an area under the curve of 0.79. Previously published risk indices based on larger numbers of variables performed similarly well in this Asian population. Large differences in risk were identified using our index to create three categories: 61% of the high-risk women had osteoporosis, compared with only 15% and 3% of the intermediate- and low-risk women, respectively. The low-risk group represented 40% of all women, for whom BMD measurements are probably not needed unless important risk factors, such as prior nonviolent fracture or corticosteroid use, are present. An existing population-based sample of postmenopausal Japanese women was used to validate our index. In this sample of Japanese women the sensitivity was 98% and specificity was 29%; the low-risk category, for whom BMD is probably unnecessary, represented 25% of all women. We conclude that our index performed well for classifying the risk of osteoporosis among postmenopausal Asian women and applying it would result in more prudent use of BMD technology.


Assuntos
Osteoporose Pós-Menopausa/diagnóstico , Inquéritos e Questionários , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Ásia/etnologia , Feminino , Humanos , Modelos Lineares , Pessoa de Meia-Idade , Análise Multivariada , Osteoporose Pós-Menopausa/etnologia , Valor Preditivo dos Testes , Fatores de Risco , Sensibilidade e Especificidade
10.
Pathology ; 32(2): 126-30, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10840834

RESUMO

Apoptosis mediated by the Apo-1/Fas and Fas ligand pathways has been implicated in many disorders, including autoimmunity and tumorigenesis. The recent identification of two polymorphisms on the 5' flanking region of the human Apo-1/Fas gene has provided useful markers for investigation of the genetic contribution of the Apo-1/Fas gene in these diseases. The Mval polymorphism at the -670 nucleotide position is frequent in the normal population, with 51% heterozygosity. The other polymorphism, a result of single nucleotide G-->A substitution at the -1377 position, does not create or delete any restriction enzyme digestion sites. In this paper, we describe a simple and rapid method for detecting the -1377 polymorphism by using allele-specific amplification (ASA). Using the ASA method, the -1377 polymorphism in a normal Caucasian population was characterised. Frequencies of 0.13 and 0.87 for allele A and G, respectively, were observed and the homozygosity of the mutant allele (A) was found in only 2% of the population. We subsequently examined the -1377 polymorphism in sporadic systemic lupus erythematosus (SLE) patients (n = 86). The results showed that both genotype distribution and allele frequencies in SLE patients were similar to that in controls, suggesting that the -1377 promoter polymorphism is unlikely to be associated with SLE susceptibility. The description of this rapid detection method and characterisation of the -1377 polymorphism are useful means for future genetic studies in diseases in which the Fas-mediated apoptosis may be involved.


Assuntos
Apolipoproteína A-I/genética , Lúpus Eritematoso Sistêmico/genética , Glicoproteínas de Membrana/genética , Polimorfismo Genético , Adulto , Idoso , Alelos , DNA/análise , Análise Mutacional de DNA , Primers do DNA/química , Proteína Ligante Fas , Feminino , Amplificação de Genes , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Linhagem , Reação em Cadeia da Polimerase/métodos
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