RESUMO
Objective: To analyze the epidemiological characteristics and economic burden of palmoplantar pustulosis (PPP) in China. Methods: A population-based retrospective study was conducted using the data from China's Urban Basic Medical Insurance data from January 1, 2012, to December 31, 2016. International Classification of Diseases code and diagnoses in Chinese for PPP were used to identify cases and estimate the prevalence, incidence, and cost. Subgroup analyses were performed according to age and sex, and sensitivity analyses were conducted to evaluate the robustness of the results. Age-adjusted prevalence rates were calculated based on the 2010 national census data. Results: The crude prevalence and incidence rate of PPP in 2016 were 2.730/100 000 (95%CI: 2.218/100 000-3.242/100 000) and 1.556/100 000 (95%CI: 1.154/100 000-1.958/100 000), and the prevalence rate of females (2.910/100 000) was higher than that of males (2.490/100 000, χ2=97.48, P=0.001). The incidence rate of females (1.745/100 000) was also higher than that of males (1.418/100 000, χ2=85.02, P=0.001). The age peak of incidence and prevalence of patients with PPP was in the 30-39-year age group and a small peak existed in the 0-3-year age group among people under 20 years old. From 2012 to 2016, the average number of visits was (2.44±0.04) per patient, and the total per-capita cost per year was (982.40±39.19) yuan. Conclusion: In 2016, the prevalence and incidence rate of PPP in China were higher in females than in males, and the highest age peak was in the 30-39-year age group.
Assuntos
Psoríase , População Urbana , Humanos , China/epidemiologia , Psoríase/epidemiologia , Psoríase/economia , Masculino , Feminino , Estudos Retrospectivos , Prevalência , Incidência , Efeitos Psicossociais da Doença , Pessoa de Meia-Idade , Adulto , Adolescente , Adulto JovemRESUMO
OBJECTIVE: To systematically review the diagnostic accuracy of Xpert® Mycobacterium tuberculosis/rifampicin (Xpert® MTB/RIF) for the detection of active tuberculosis (TB) and rifampicin-resistance TB in Chinese patients. METHODS: Four Chinese databases (SinoMed, CNKI, WanFang database, and VIP) and three English databases (PubMed, Embase, and The Cochrane Library) were searched from January 1, 2000 to September 15, 2017, to identify diagnostic tests about the accuracy of Xpert® MTB/RIF in Chinese patients. Two investigators screened the articles and extracted the information independently, and then the quality of each included study was evaluated by Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2. Bivariate random-effects meta-analysis was conducted to pool the sensitivity and specificity. In addition, subgroup analyses were performed based on patient type (TB patient and TB suspected patient), sample type (sputum, bronchoalveolar lavage fluid and others). All statistical analyses were conducted with Stata version 13.0. RESULTS: A total of 47 articles were included in this systematic review. Most of them (38 articles) were in Chinese and only 9 articles were in English. All the articles were published during 2014 to 2017, and the sample size ranged from 31 to 3 151. Forty articles including 42 comparisons about TB were finally included with the pooled sensitivity of 0.94 (95%CI: 0.92, 0.95) and the pooled specificity of 0.87 (95%CI: 0.84, 0.91). Subgroup analysis showed that different patient and specimen types had no significant differences on sensitivity, but the specificity of sputum group was higher than that of bronchoalveolar lavage fluid. As for the detection of rifampicin-resistant TB, 33 articles (38 comparisons) were analyzed, the pooled sensitivity and specificity were 0.92 (95%CI: 0.89, 0.94) and 0.98 (95%CI: 0.97, 0.99) respectively. There were no significant differences between the patient and specimen in the subgroup analyses. The Deeks funnel plot showed a possible publication bias for detecting active tuberculosis (P=0.08) and no publication bias for rifampicin-resistant TB (P=0.24). The likelihood ratio scatter gram showed that in clinical applications, Xpert® MTB/RIF had a good diagnostic ability for detecting active tuberculosis, and it had good clinical diagnostic value in detecting rifampicin-resistant TB. CONCLUSION: Xpert® MTB/RIF has good sensitivity and specificity in detecting TB and rifampicin-resistant TB in Chinese people. In particular, it has good clinical value in diagnosing rifampicin-resistance TB.
Assuntos
Antibióticos Antituberculose , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose Pulmonar , Tuberculose , Antibióticos Antituberculose/farmacologia , Antibióticos Antituberculose/uso terapêutico , China , Testes Diagnósticos de Rotina , Farmacorresistência Bacteriana , Humanos , Rifampina/farmacologia , Sensibilidade e Especificidade , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/tratamento farmacológicoRESUMO
OBJECTIVE: To analyze the characteristics of patients with progressive muscular atrophy (PMA) and calculate the prevalence of PMA in China in 2016. METHODS: A retrospective analysis based on China's urban employee basic medical insurance data and the urban residence basic medical insu-rance data from January 1, 2016 to December 31, 2016 was carried out. Children under 18 years old were excluded. Patients with progressive muscular atrophy were identified by disease names and codes. Subgroup analyses by gender, region and age were carried out to calculate the gender-specific, region-specific and age-specific prevalences. Age-adjusted national prevalence was estimated based on 2010 Chinese census data. Sensitivity analyses were done by only considering the observed cases and by excluding the top 10% provinces regarding the missing rate of diagnostic information, respectively. RESULTS: A total of 996.09 million person-years were included in this study, with 518.41 million person-years in males and 477.67 million person-years in females. The age and gender distribution of the study population was similar to that of the 2010 Chinese census data, therefore the study population was nationally representative. The prevalence of PMA in China in 2016 was 0.28 per 100 000 person-years (95%CI: 0.24-0.33), with 0.21 per 100 000 person-years (95%CI: 0.16-0.26) and 0.35 per 100 000 person-years (95%CI: 0.28-0.42) for females and males, respectively. Regional disparity existed in the Chinese PMA prevalence, with the lowest prevalence in Southwest region (0.11 per 100 000 person-years, 95%CI: 0.07-0.15) and the highest prevalence in Northwest region (3.47 per 100 000 person-years, 95%CI: 0.80-7.99). Age trend in the PMA prevalence was not obvious, but the prevalence among those aged 70 years and older was relatively higher. The age-adjusted prevalence based on 2010 Chinese census data was 0.29 per 100 000 person-years (95%CI: 0.27-0.31). The national prevalences calculated by only considering the observed cases and by excluding the top 10% provinces regar-ding the missing rate of diagnostic information were 0.17 per 100 000 person-years (95%CI: 0.14-0.20) and 0.24 per 100 000 person-years (95%CI: 0.20-0.28), respectively. CONCLUSION: This study is to calculate the prevalence of PMA among adults in urban China, which can provide basic statistics for the enactment of PMA related medical policies, and clues for the studies on the mechanisms of PMA.
Assuntos
Atrofia Muscular Espinal , Adulto , Idoso , China , Feminino , Humanos , Masculino , Prevalência , Estudos Retrospectivos , População UrbanaRESUMO
The human breast cancer-associated gene (BCA3) was first discovered in breast and prostate cancer cells lines. In vivo studies have shown that BCA3 is mainly expressed in breast tumor cells and not in normal breast and prostate tissues. To date, 3 splice variants of BCA3 have been reported: a double-absent variant lacking exon 3 and exon 5 (BCA3-1), an exon 3-absent variant (BCA3-2), and full-length BCA3. In this study, we investigated whether a novel BCA3 splice variant exists that lacks only the exon 5-encoding sequence. BCA3 variant splices were subcloned and sequenced using reverse transcription-polymerase chain reaction. The preliminary biological functions of the splices were identified using confocal microscopy and a luciferase assay. The absence of exon 3 and exon 5 influenced the subcellular localization of BCA3 and nuclear factor kappa B (NF-kB)-dependent gene expression. Exon 3 and exon 5 of BCA3 may function together to provide a nuclear localization signal or transport sequence to enter the nucleus, and exon 3 may contain specific sequence(s) or domain(s) that influence the NF-κB signal cascade. The discovery of novel BCA3 splicing indicates a new cancer research area, which may increase the understanding of cancer generation and development.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Nucleares/metabolismo , Splicing de RNA , Proteínas Adaptadoras de Transdução de Sinal/genética , Linhagem Celular , Clonagem Molecular , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Éxons , Humanos , NF-kappa B/metabolismo , Proteínas Nucleares/genética , FosforilaçãoRESUMO
Obstructive sleep apnea hypopnea syndrome (OSAHS) is a common sleep respiratory disorder characterized by upper respiratory collapse during sleep, with a high prevalence and potentially fatal complications. Currently, maxillary transverse deficiency are considered to be an important pathogenic factor of OSAHS. For patients with poor compliance with positive airway pressure therapy, rapid maxillary expansion can increase the volume and ventilation of the upper respiratory tract, which is an alternative treatment. This paper reviewed the current research on surgically assisted rapid palatal expansion, miniscrew assisted rapid palatal expansion, and distraction osteogenesis maxillary expansion in the treatment of adult OSAHS. By comparing the indications, contraindications, complications, efficacy and long-term stability of the three treatment methods, it provided reference for treatment of patients with OSAHS.
Assuntos
Técnica de Expansão Palatina , Apneia Obstrutiva do Sono , Adulto , Humanos , Nariz , Palato , Apneia Obstrutiva do Sono/cirurgia , SíndromeRESUMO
Objective: To understand the current status of rare disease related health information release in WeChat official accounts in China. Methods: We used a series of key words containing "rare diseases" and the names of the top 30 rare diseases in hospitalizations in China to search WeChat official accounts. Eligible articles were selected by systematic sampling. All including WeChat official accounts and articles were evaluated to extract the basic information. Results: No relevant WeChat official accounts were found for 14 rare diseases (46.67%). Most of the WeChat official accounts (52.17%) were initiated by patients and patient groups. No significant difference was detected in the total number of articles between the official accounts related with Traditional Chinese Medicine (TCM) and non-TCM related ones, however, the frequency of the monthly information release was significantly higher in TCM related official accounts (P<0.001), while the average reading number of articles was significantly higher in non-TCM related official accounts (P<0.001). Nearly 80% of the WeChat official accounts had navigation menu, and the average reading number of official accounts with menus was larger than those without menus. The top three topics were rare disease diagnosis and treatment knowledge (46.00%), public welfare activity for rare diseases (12.81%) and uncorrelated things (8.65%), while the first three leading topics were cutting-edge information, public welfare activity and patient story, respectively. Conclusions: The scale for rare disease related health information release based on WeChat official accounts in China has been basically formed, but it is still in development stage. Many improvements should be made in their coverage of rare diseases, release frequency, topic and form. It is urgent to establish or recreate some high-quality WeChat official accounts in order to provide precise information and effectively facilitate the prevention and treatment of rare diseases.
Assuntos
Informação de Saúde ao Consumidor/estatística & dados numéricos , Doenças Raras , China , Estudos Transversais , HumanosRESUMO
Objective: To analyze the epidemiological features of patients with plasma cell leukemia (PCL) and calculate the prevalence of PCL in urban China in 2016. Methods: Calculation in this study was based on China's urban basic medical insurance from 23 provinces between January 1, 2016 and December 31, 2016. The identification of the patients with PCL was based on the disease names and codes in the claim data. Subgroup analyses were carried out by sex, region, and age. To test the robustness of the results, we performed sensitivity analyses. Age-adjusted prevalence was calculated, based on the 2010 Chinese census data. Results: The prevalence of PCL in urban China in 2016 was 0.11 per 100 000 population (95% CI 0.05-0.19) , and the male prevalence and female prevalence were 0.12 per 100 000 population (95% CI 0.06-0.21) and 0.10 per 100 000 population (95% CI 0.04-0.19) , respectively. The prevalence of PCL peaked at 70-79 years old. Sensitivity analyses proved the robustness of the primary result. The age-adjusted prevalence based on 2010 Chinese census data was 0.12 per 100 000 population (95% CI 0.11-0.13) . Conclusion: This study firstly analyzed the epidemiological characteristics of PCL in China, which can provide evidence for the research and policies regarding PCL.
Assuntos
Seguro , Leucemia Plasmocitária , Idoso , Povo Asiático , China/epidemiologia , Feminino , Humanos , Leucemia Plasmocitária/epidemiologia , Masculino , PrevalênciaRESUMO
Objective: The aim of this study is to analyze the distribution features of patients with solitary plasmacytoma and calculate the prevalence of solitary plasmacytoma in China in the year 2016. Methods: This study was based on China's urban employees' basic medical insurance and the urban residences' basic medical insurance from 21 provinces from January 1, 2016 to December 31, 2016. Patients with solitary plasmacytoma were identified by disease names and codes. Subgroup analyses were carried out by sex, region, and age. Furthermore, sensitivity analyses were performed to test the robustness of the results. Age-adjusted prevalence was calculated based on the 2010 Chinese census data, the 2013 Revised European Standard Population, the 2010 US population, and the 2011 Australian population. Results: In 2016, the prevalence of solitary plasmacytoma in China was 1.18 per 100 000 population (95%CI, 1.06-1.31) , with 1.26 per 100 000 population (95% CI, 1.10-1.43) and 1.10 per 100 000 population (95% CI, 0.93-1.29) for males and females, respectively. The age-adjusted prevalence based on the 2010 Chinese census data was 0.85 per 100 000 population (95% CI, 0.82-0.88) . Conclusion: This study estimated the prevalence of solitary plasmacytoma in China on the basis of the national urban medical insurance, which can provide clues for the enactment of solitary plasmacytoma-related medical policies and basic studies about solitary plasmacytoma.
Assuntos
Plasmocitoma , China/epidemiologia , Feminino , Humanos , Seguro Saúde , Masculino , Plasmocitoma/epidemiologia , PrevalênciaRESUMO
Medical claims database is an important source of data for studying the characteristics, and burden of diseases, to provide a basis for the development of policy on management. The database is usually used to identify patients through International Classification of Diseases and free text-building algorithms, thus it is crucial to validate whether the algorithm is correctly identifing the targeted population. This paper introduces both traditional and emerging validation methods including machine learning, natural language processing and database linkage etc.. We also have tried to present a suitable validation method for the current situation in China, so as to promote the application of big data in medical areas and to provide reference for epidemiology studies, based on medical claims database in this country.
Assuntos
Algoritmos , Bases de Dados Factuais , Classificação Internacional de Doenças , Aprendizado de Máquina , China , HumanosRESUMO
Two novel P450 cDNAs, CYP6A36 and CYP6A37, were isolated from house-flies. Putative protein sequences deduced from the cDNA sequences shared 58% identity. Predicted protein sequences of CYP6A36 and CYP6A37 from pyrethroid-resistant ALHF house-flies were identical to their corresponding orthologues in susceptible aabys flies. Expression of CYP6A36 was developmentally regulated with significant overexpression in ALHF compared with susceptible CS flies. Overexpression of CYP6A36 was detected in ALHF abdomen, where the primary detoxification organs of the midgut and fat body are located. CYP6A37, however, was expressed in all tested life stages, with no significant difference in expression between ALHF and CS. Genetic linkage analysis located CYP6A36 on autosome 5; overexpression of CYP6A36 was linked to the factors on autosomes 1 and 2, corresponding to the linkage of P450-mediated resistance in ALHF. This evidence suggests the importance of CYP6A36 in detoxification of insecticides and evolution of insecticide resistance in ALHF.
Assuntos
Sistema Enzimático do Citocromo P-450/genética , Moscas Domésticas/enzimologia , Moscas Domésticas/genética , Resistência a Inseticidas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Clonagem Molecular , Cruzamentos Genéticos , Sistema Enzimático do Citocromo P-450/biossíntese , DNA Complementar/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Ligação Genética , Inseticidas , Isoenzimas , Masculino , Dados de Sequência Molecular , Permetrina , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de SequênciaRESUMO
Filamentous phage assemble at the membrane of infected cells. The phage filament is released from the membrane at the end of assembly, after four to five copies of the minor proteins, pIII and pVI, have been added to the end of the virion. In the absence of pIII or pVI, phage filaments are not released, but remain associated with the cells. The C-terminal portion of pIII, termed the "C" domain, is required for the release of stable virions. With the use of pIII C-terminal fragments of increasing size, termination of assembly can be divided into various steps. An 83-residue fragment leads to the incorporation of pVI into the assembling phage, but does not release it from the membrane. A slightly longer fragment (93 residues) is sufficient to release the particle into the culture supernatant. However, these released particles are unstable in the detergent, sarkosyl, which does not disrupt wild-type phage. A fragment of >121 residues is needed for the particle to become detergent resistant. Thus, the C-domain can be divided into two subdomains: C2, sufficient for release, and C1, required for virion stability.A model for termination of phage assembly is proposed in which pIII and pVI dock to the membrane-associated filament and form a pre- termination complex. Then, a conformational change involving the C2 domain of pIII disrupts the hydrophobic interactions with the inner membrane, releasing the phage from the cells. The pIII-mediated release of phage from the membranes points to one possible mechanism for excision of membrane-anchored protein complexes from lipid bilayers.
Assuntos
Colífagos/fisiologia , Proteínas de Ligação a DNA/fisiologia , Proteínas Virais de Fusão/fisiologia , Montagem de Vírus , Proteínas do Capsídeo , Membrana Celular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/virologia , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/metabolismo , VírionRESUMO
Based on our finding that a similar epitope exists between human IFN-beta (aa128-134) and HIV-1 gp41 (aa586-595), we examined 20 sera from healthy and 20 from HIV-1 infected individuals for IFN-beta antibody levels by ELISA. The levels of anti-IFN-beta antibody in sera from HIV-infected individuals were increased by about 160% in comparison with HIV-negative. We affinity-purified anti-gp41 antibodies from sera of HIV-1-infected individuals using rsgp41-sepharose column. One of three antibodies could recognize human IFN-beta in comparison with antibodies from serum of a healthy individual. A mouse antiserum to human IFN-beta recognized rsgp41 (recombinant soluble gp41 Env amino acid 539-684), while the normal mouse serum (pre-immune serum) did not bind to rspg41. These results indicate that a common immunological epitope exists between human IFN-beta and HIV-1 gp41. The sequence-similarity suggests that this common immunological epitope may be located in the region aa128-134 of human IFN-beta and the immunosuppressive domain (aa583-599) of HIV-1 gp41. The increased levels of antibodies against interferon-beta in HIV-1 positive individuals may be explained by a common immunological epitope on human IFN-beta and HIV-1 gp41.
Assuntos
Epitopos/imunologia , Proteína gp41 do Envelope de HIV/imunologia , Soropositividade para HIV/imunologia , Interferon beta/imunologia , Adulto , Sequência de Aminoácidos , Animais , Anticorpos/imunologia , Especificidade de Anticorpos , Reações Cruzadas , Humanos , Camundongos , Dados de Sequência MolecularRESUMO
erbB2 oncogene encodes a growth factor receptor. The overexpression of erbB2 was correlated with more aggressive tumors and a poorer prognosis. Some antibodies directed to this molecule have an antitumor effect in vivo, but some antibodies do not. In an attempt to understand the molecular basis of the anti-erbB2 antibody interaction with erbB2 ectodomain (ECD), we analyzed binding epitopes on erbB2 for inhibitory and non-inhibitory antibodies, Herceptin and HF by computer-guided protein engineering and site-directed mutagenesis. Two different interaction domains were identified by molecular docking, computer graphics and distance geometry method and confirmed through studies on a series of mutants of erbB2 ECD. Non-inhibitory antibody HF only recognized N-terminal portion of erbB2 ECD, but inhibitory antibody Herceptin bound to C-terminal portion of it exclusively. The region interacted with inhibitory antibody Herceptin can be an important target for anticancer therapies.
Assuntos
Anticorpos Monoclonais/imunologia , Epitopos/imunologia , Receptor ErbB-2/imunologia , Anticorpos Monoclonais/química , Anticorpos Monoclonais Humanizados , Neoplasias da Mama/imunologia , Feminino , Genes Reporter/genética , Genes Reporter/imunologia , Humanos , Receptor ErbB-2/química , Receptor ErbB-2/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Análise de Sequência de Proteína , Trastuzumab , Células Tumorais CultivadasRESUMO
Colitis-associated colorectal cancer (CAC) is the most serious complication of inflammatory bowel disease (IBD). Excessive complement activation has been shown to be involved in the pathogenesis of IBD. However, its role in the development of CAC is largely unknown. Here, using a CAC model induced by combined administration of azoxymethane (AOM) and dextran sulfate sodium (DSS), we demonstrated that complement activation was required for CAC pathogenesis. Deficiency in key components of complement (e.g., C3, C5, or C5a receptor) rendered tumor repression in mice subjected to AOM/DSS. Mechanistic investigation revealed that complement ablation dramatically reduced proinflammatory cytokine interleukin (IL)-1ß levels in the colonic tissues that was mainly produced by infiltrating neutrophils. IL-1ß promoted colon carcinogenesis by eliciting IL-17 response in intestinal myeloid cells. Furthermore, complement-activation product C5a represented a potent inducer for IL-1ß in neutrophil, accounting for downregulation of IL-1ß levels in the employed complement-deficient mice. Overall, our study proposes a protumorigenic role of complement in inflammation-related colorectal cancer and that the therapeutic strategies targeting complement may be beneficial for the treatment of CAC in clinic.
Assuntos
Carcinogênese/imunologia , Colite/patologia , Neoplasias Colorretais/patologia , Ativação do Complemento/fisiologia , Interleucina-17/metabolismo , Interleucina-1beta/metabolismo , Animais , Transformação Celular Neoplásica/imunologia , Transformação Celular Neoplásica/metabolismo , Colite/imunologia , Colite/metabolismo , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/metabolismo , Progressão da Doença , Citometria de Fluxo , Immunoblotting , Imuno-Histoquímica , Mucosa Intestinal/metabolismo , Intestinos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/imunologiaRESUMO
This is the first report on human toxicosis in China caused by moldy rice contaminated with Fusarium and T-2 toxin due to heavy rainfall during rice harvest season. One hundred and sixty-five persons ate the moldy rice and ninety-seven persons fall ill of food poisoning. The incidence was 58.8% and latent period was 10-30 min. The chief symptoms were nausea, dizziness, vomiting, chills, abdominal distension, abdominal pain, thoracic stuffiness and diarrhea. The fungi isolated from the moldy rice were predominantly Fusarium heterosporum (F. heterosporum) and F. graminearum. T-2 toxin was found in these moldy rice and the highest level was 420 ppb. The chief causative agent of intoxication was T-2 toxin.
Assuntos
Surtos de Doenças , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/etiologia , Fusarium/isolamento & purificação , Oryza/microbiologia , Toxina T-2/intoxicação , China/epidemiologia , Feminino , Doenças Transmitidas por Alimentos/epidemiologia , Fusarium/química , Humanos , Masculino , Oryza/química , Toxina T-2/análiseRESUMO
The BcII polymorphism within DXS52 (St14) was reported. It was composed of 4 allelic fragments, 4.0 kb, 3.3 kb, 3.0 kb and 2.3 kb. The frequency of these fragment were 0.09, 0.12, 0.44 and 0.35 respectively in the Chinese. The polymorphism provided the PIC of 0.66. DNA analysis of families with hemophilia A showed that the confidence of the RFLPs was the same as the TaqI/St14 RFLPs and for carrier detection the former is much better than that of the TaqI/St14 RFLPs.
Assuntos
Doenças Fetais/diagnóstico , Hemofilia A/diagnóstico , Polimorfismo de Fragmento de Restrição , Diagnóstico Pré-Natal , China , Sondas de DNA , Feminino , Triagem de Portadores Genéticos , Hemofilia A/genética , Humanos , Masculino , Linhagem , GravidezRESUMO
An epidemic of food poisoning in human beings occurred in Tongxiang County, Zhejiang Province after eating mouldy rice contaminated with Fusarium and toxins. Continuous rainfall took place during the rice harvest season. The number of patients poisoned was 97, the rate of incidence was 58.8%. The incubation period was 10 to 30 minutes. The chief symptoms were nausea, dizziness, vomiting, chills, abdominal distension, abdominal pain and diarrhea. The fungi isolated from the mouldy rice were predominantly Fusarium heterosporum and F. graminearum. T-2 toxin was found in the mouldy rice and the highest content was 420 ppb.
Assuntos
Contaminação de Alimentos , Microbiologia de Alimentos , Fusarium/isolamento & purificação , Oryza/intoxicação , Toxina T-2/análise , China/epidemiologia , Doenças Transmitidas por Alimentos/epidemiologia , Humanos , Incidência , Oryza/microbiologiaRESUMO
A permeabilized cell system has been developed that is capable of assembling filamentous phage only upon addition of exogenous thioredoxin. The in vitro system exhibits the same component requirements seen in vivo: functional thioredoxin, an intact packaging signal in the substrate DNA, and the assembly protein, pIV. This crude in vitro system is insensitive to inhibitors of protein or DNA synthesis, demonstrating that particle assembly uses components that had accumulated before cell permeabilization. The temporal separation of the synthetic period, during which phage proteins and DNA accumulate, from the assembly period enabled us to examine the energy requirement for assembly. We show here that ATP hydrolysis is required for filamentous phage assembly and that the proton motive force is also important.
Assuntos
Bacteriófagos/fisiologia , Membrana Celular/virologia , Técnicas de Cultura de Células/métodos , Replicação do DNA , DNA Viral , Força Próton-Motriz , Replicação ViralRESUMO
Assembly and export of filamentous phage requires four non-capsid proteins: the outer membrane protein, pIV; the inner membrane proteins, pI and pXI; and a cytoplasmic host factor, thioredoxin. Chemical cross-linking of intact cells demonstrates a trans-membrane complex containing pI and pIV. Formation of the complex protects pI from proteolytic cleavage by an endogenous protease. This protection also requires pXI, which is identical to the C-terminal portion of pI. This indicates that pXI, which is required for phage assembly in its own right, is also part of the complex. This complex forms in the absence of any other phage proteins or the DNA substrate; hence, it represents the first preinitiation step of phage morphogenesis. On the basis of protease protection data, we propose that the preinitiation complex is converted to an initiation complex by binding phage DNA, thioredoxin and the initiating minor coat protein(s).
Assuntos
Bacteriófagos/fisiologia , Capsídeo/fisiologia , Montagem de Vírus , Bacteriófagos/efeitos dos fármacos , Sítios de Ligação , Capsídeo/genética , Reagentes de Ligações Cruzadas/farmacologia , Endopeptidases/metabolismo , Endopeptidases/farmacologia , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Montagem de Vírus/efeitos dos fármacosRESUMO
We have reconstituted the transposition of the bacterial transposon Tn7 into its specific insertion site attTn7 with four purified Tn7-encoded proteins, TnsA+TnsB+TnsC+TnsD, and ATP. TnsA+TnsB+TnsC form a "core" recombination machine that recognizes the transposon ends and executes DNA breakage and joining; TnsD specifically recognizes attTn7. TnsA+TnsB+TnsC are specifically targeted to attTn7 through the TnsD-dependent interaction of TnsC, a nonspecific DNA-binding protein, with attTn7. Recombination appears to be activated by the assembly of a nucleoprotein complex containing the DNA substrates and Tns proteins. We suggest that TnsC plays a central role in communication between the transposon and the target DNA, particularly in directing insertion away from DNAs already containing a copy of Tn7.