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Peritoneal metastases are frequently found in high-grade serous carcinoma (HGSOC) patients and are commonly associated with a poor prognosis. The tumor microenvironment (TME) is a complex milieu that plays a critical role in epigenetic alterations driving tumor development and metastatic progression. However, the impact of epigenetic alterations on metastatic ovarian cancer cells in the harsh peritoneal microenvironment remains incompletely understood. Here, we identified that miR-33b is frequently silenced by promoter hypermethylation in HGSOC cells derived from metastatic omental tumor tissues. Enforced expression of miR-33b abrogates the oncogenic properties of ovarian cancer cells cocultured in omental conditioned medium (OCM), which mimics the ascites microenvironment, and in vivo tumor growth. Of note, restoration of miR-33b inhibited OCM-upregulated de novo lipogenesis and fatty acid ß-oxidation in ovarian cancer cells, indicating that miR-33b may play a novel tumor suppressor role in the lipid-mediated oncogenic properties of metastatic ovarian cancer cells found in the omentum. Mechanistic studies demonstrated that miR-33b directly targets transforming growth factor beta-activated kinase 1 (TAK1), thereby suppressing the activities of fatty acid synthase (FASN) and carnitine palmitoyltransferase 1A (CPT1A) in modulating lipid metabolic activities and simultaneously inhibiting the phosphorylation of NF-κB signaling to govern the oncogenic behaviors of ovarian cancer cells. Thus, our data suggest that a lipid-rich microenvironment may cause epigenetic silencing of miR-33b, which negatively modulates ovarian cancer peritoneal metastases, at least in part, by suppressing TAK1/FASN/CPT1A/NF-κB signaling.
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BACKGROUND: In contrast to stable genetic events, epigenetic changes are highly plastic and play crucial roles in tumor evolution and development. Epithelial ovarian cancer (EOC) is a highly heterogeneous disease that is generally associated with poor prognosis and treatment failure. Profiling epigenome-wide DNA methylation status is therefore essential to better characterize the impact of epigenetic alterations on the heterogeneity of EOC. METHODS: An epigenome-wide association study was conducted to evaluate global DNA methylation in a retrospective cohort of 80 mixed subtypes of primary ovarian cancers and 30 patients with high-grade serous ovarian carcinoma (HGSOC). Three demethylating agents, azacytidine, decitabine, and thioguanine, were tested their anti-cancer and anti-chemoresistant effects on HGSOC cells. RESULTS: Global DNA hypermethylation was significantly associated with high-grade tumors, platinum resistance, and poor prognosis. We determined that 9313 differentially methylated probes (DMPs) were enriched in their relative gene regions of 4938 genes involved in small GTPases and were significantly correlated with the PI3K-AKT, MAPK, RAS, and WNT oncogenic pathways. On the other hand, global DNA hypermethylation was preferentially associated with recurrent HGSOC. A total of 2969 DMPs corresponding to 1471 genes were involved in olfactory transduction, and calcium and cAMP signaling. Co-treatment with demethylating agents showed significant growth retardation in ovarian cancer cells through differential inductions, such as cell apoptosis by azacytidine or G2/M cell cycle arrest by decitabine and thioguanine. Notably, azacytidine and decitabine, though not thioguanine, synergistically enhanced cisplatin-mediated cytotoxicity in HGSOC cells. CONCLUSIONS: This study demonstrates the significant association of global hypermethylation with poor prognosis and drug resistance in high-grade EOC and highlights the potential of demethylating agents in cancer treatment.
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Resistência a Medicamentos/genética , Epigenoma/genética , Neoplasias Ovarianas/genética , Metilação de DNA/efeitos dos fármacos , Resistência a Medicamentos/fisiologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/mortalidade , Estudos RetrospectivosRESUMO
Immunocompetent metastatic head and neck cancer (HNC) models, although scarce, can help understanding cancer progression and therapy responses in vivo. Their comprehensive genome characterizations are essential for translational research. We first exome-sequenced the two most widely used spontaneous metastatic immunocompetent models, namely AT-84 and SCC VII, followed by comprehensive genomic analyses with three prior-sequenced models (MOC2, MOC2-10, and 4MOSC2), together with patient tumors for utility assessment. AT-84 and SCC VII bear high HNC tumor resemblance regarding mutational signatures-Trp53, Fanconi anemia, and MAPK and PI3K pathway defects. Collectively, the five models harbor genetic aberrations across 10 cancer hallmarks and 14 signaling pathways and machineries (metabolic, epigenetic, immune evasion), to extents similar in patients. Immune defects in HLA-A (H2-Q10, H2-Q4, H2-Q7, and H2-K1), Pdcd1, Tgfb1, Il2ra, Il12a, Cd40, and Tnfrsf14 are identified. Invasion/metastatic genome analyses first highlight potential druggable ERBB4 and KRAS mutations, for advanced/metastatic oral cavity cancer, as well as known metastasis players (Muc5ac, Trem3, Trp53, and Ttn) frequently captured by all models. Notable immunotherapy and precision druggable targets (Pdcd1, Erbb4, Fgfr1, H/Kras, Jak1, and Map2k2) and three druggable hubs (RTK family, MAPK, and DNA repair pathways) are frequently represented by these models. Immunocompetent metastatic HNC models are worth developing to address therapy- and invasion/metastasis-related questions in host immunity contexts.
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The anaplastic lymphoma kinase (ALK) is a druggable target for cancer therapy. By and large, the oncogenic activation of ALK in human tumors is known to occur by gene rearrangement (e.g. EML4-ALK, NMP-ALK, etc.). Clinical use of ALK inhibitors for "ALK-rearranged" lung cancers has remarkably improved patient survival. To date, much has been known about ALK gene rearrangement in human carcinogenesis and its drug sensitivity relationship. However, emerging genomic data from the Cancer Genome Atlas (TCGA, USA) are now revealing common ALK point mutations (~3.06%) in various cancer types other than lung cancer. Importantly, several recent studies have demonstrated that ALK point mutations, independent of ALK-gene rearrangement, can be oncogenic. Thus, ALK mutations can be pathogenically and perhaps therapeutically important for various cancer types. Here, we summarized the latest ALK mutation frequencies and mutation patterns across 17 human cancer types stemming from TCGA. Unlike many other oncogenes with high frequency of hotspot mutations, ALK point mutations tend to span along the entire gene. Up till now, several recurrent mutations (G263, R401, R551, P968 and E1242) and mutation-rich cluster regions have been identified, but their functional effects remain unknown. We also conducted a comprehensive review of all ALK-mutated human cancer cell lines (from the Cell Line Encyclopedia (CCLE) and the NCI-60 panel), which can be used as model systems for ALK mutation biology and drug screening studies. Lastly, we summarized both the preclinical and clinical findings of ALK mutations on carcinogenesis and drug sensitivity, which may provide important insight into new treatment strategies and prompt future ALK mutation studies in various cancer types.
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Antineoplásicos/farmacologia , Terapia de Alvo Molecular/métodos , Mutação , Neoplasias , Receptores Proteína Tirosina Quinases/genética , Quinase do Linfoma Anaplásico , Carcinogênese/genética , Amplificação de Genes , Rearranjo Gênico , Estudo de Associação Genômica Ampla , Humanos , Neoplasias/classificação , Neoplasias/genética , Neoplasias/terapiaRESUMO
Clostridium butyricum is one of the species frequently present in patients' stool samples. However, the identification of this species is sometimes difficult. Here, we present the draft genome of Clostridium butyricum NOR 33234, which was isolated from a patient with suspected Clostridium difficile infection-associated diarrhea and resembles Clostridium clostridioforme in biochemical tests.
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We report the draft genome sequence of a methicillin-resistant Staphylococcus aureus strain designated CUHK_188, isolated from a bacteremic patient undergoing treatment at a university teaching hospital in Hong Kong. This strain belongs to sequence type 188 (ST188), with spa type t189 and staphylococcal cassette chromosome mec type V.
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BACKGROUND: Avian influenza remains a serious threat to human health. The consequence of human infection varies markedly among different subtypes of avian influenza viruses. In addition to viral factors, the difference in host cellular response is likely to play a critical role. This study aims at elucidating how avian influenza infection perturbs the host's miRNA regulatory pathways that may lead to adverse pathological events, such as cytokine storm, using the miRNA microarray approach. RESULTS: The results showed that dysregulation of miRNA expression was mainly observed in highly pathogenic avian influenza A H5N1 infection. We found that miR-21*, miR-100*, miR-141, miR-574-3p, miR-1274a and miR1274b were differentially expressed in response to influenza A virus infection. Interestingly, we demonstrated that miR-141, which was more highly induced by H5N1 than by H1N1 (p < 0.05), had an ability to suppress the expression of a cytokine - transforming growth factor (TGF)-ß2. This was supported by the observation that the inhibitory effect could be reversed by antagomiR-141. CONCLUSIONS: Since TGF-ß2 is an important cytokine that can act as both an immunosuppressive agent and a potent proinflammatory molecule through its ability to attract and regulate inflammatory molecules, and previous report showed that only seasonal influenza H1N1 (but not the other avian influenza subtypes) could induce a persistent expression of TGF-ß2, we speculate that the modulation of TGF-ß2 expression by different influenza subtypes via miR-141 might be a critical step for determining the outcome of either normal or excessive inflammation progression.
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Células Epiteliais/virologia , Interações Hospedeiro-Patógeno , Virus da Influenza A Subtipo H5N1/patogenicidade , MicroRNAs/biossíntese , Linhagem Celular , Perfilação da Expressão Gênica , HumanosRESUMO
BACKGROUND: Tuberculosis (TB) remains a global threat in the 21st century. Traditional studies of the disease are focused on the single pathogen Mycobacterium tuberculosis. Recent studies have revealed associations of some diseases with an imbalance in the microbial community. Characterization of the TB microbiota could allow a better understanding of the disease. METHODOLOGY/PRINCIPAL FINDINGS: Here, the sputum microbiota in TB infection was examined by using 16S rRNA pyrosequencing. A total of 829,873 high-quality sequencing reads were generated from 22 TB and 14 control sputum samples. Firmicutes, Proteobacteria, Bacteroidetes, Actinobacteria, and Fusobacteria were the five major bacterial phyla recovered, which together composed over 98% of the microbial community. Proteobacteria and Bacteroidetes were more represented in the TB samples and Firmicutes was more predominant in the controls. Sixteen major bacterial genera were recovered. Streptococcus, Neisseria and Prevotella were the most predominant genera, which were dominated by several operational taxonomic units grouped at a 97% similarity level. Actinomyces, Fusobacterium, Leptotrichia, Prevotella, Streptococcus, and Veillonella were found in all TB samples, possibly representing the core genera in TB sputum microbiota. The less represented genera Mogibacterium, Moryella and Oribacterium were enriched statistically in the TB samples, while a genus belonging to the unclassified Lactobacillales was enriched in the controls. The diversity of microbiota was similar in the TB and control samples. CONCLUSIONS/SIGNIFICANCE: The composition and diversity of sputum microbiota in TB infection was characterized for the first time by using high-throughput pyrosequencing. It lays the framework for examination of potential roles played by the diverse microbiota in TB pathogenesis and progression, and could ultimately facilitate advances in TB treatment.
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Bactérias/genética , Metagenoma/genética , RNA Ribossômico 16S/genética , Escarro/microbiologia , Tuberculose Pulmonar/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bactérias/classificação , Bactérias/isolamento & purificação , Biodiversidade , Estudos de Casos e Controles , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , RNA Ribossômico 16S/classificação , Análise de Sequência de DNARESUMO
BACKGROUND: Little is known about the virological and inflammatory responses of severe pandemic 2009 influenza A(H1N1) virus pneumonia during antiviral treatment. METHODS: In a prospective observational study, we recruited consecutive adults hospitalized with confirmed pandemic 2009 H1N1 infection during a 16-week period. Nasopharyngeal aspirate and non-respiratory samples (blood, stool and urine) were collected at presentation, and serial nasopharyngeal flocked swabs (NPFS) and tracheal aspirates (TA) were collected after initiating oseltamivir treatment for quantitative viral RNA assay, using real-time reverse transcriptase-PCR. Serial plasma samples were collected for cytokine/chemokine assay using cytometric bead array. Patients with severe pneumonia (lung infiltrates and hypoxaemia) were compared to those with milder illnesses. RESULTS: A total of 66 patients were studied (mean age 43 ±20 years); 28 (42%) developed severe pneumonia, of whom 10 (15%) required intubation. Severe pneumonia was associated with older age, dyspnoea, delayed presentation >2 days from onset, extrapulmonary virus detection (13-28%) and higher viral concentration despite late-presentation (multiple linear regression, ß=0.94, 95% confidence interval 0.15-1.74; P=0.02). Patients with severe pneumonia exhibited slow viral clearance with oseltamivir treatment, particularly in the lower respiratory tract (median [interquartile range] durations of RNA positivity after antiviral initiation were NPFS 6.0 days [3.0-8.0], TA 11.0 days [7.8-14.3] versus milder illness group NPFS of 2.0 days [1.0-3.0] days; P<0.01). High viral load in lower respiratory tract despite upper-tract RNA negativity and viral rebound after stopping treatment were noted in some patients. H275Y mutation was absent. High plasma levels of interleukin (IL)-6, CXCL-8 (IL-8), CCL2 (monocyte chemoattractant protein-1) and soluble tumour necrosis factor receptor-1 were observed, which correlated with the extent and progression of pneumonia in hospital. CONCLUSIONS: In severe 2009 H1N1 pneumonia, viral clearance is slow with treatment, particularly in the lower respiratory tract. A more sustained antiviral regime appears warranted.
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Antivirais/uso terapêutico , Hospitalização/estatística & dados numéricos , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/epidemiologia , Pandemias , Adolescente , Adulto , Citocinas/metabolismo , Feminino , Humanos , Inflamação/imunologia , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/tratamento farmacológico , Influenza Humana/imunologia , Influenza Humana/fisiopatologia , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/fisiopatologia , Pneumonia Viral/virologia , RNA Viral/análise , Índice de Gravidade de Doença , Traqueia/virologia , Adulto JovemRESUMO
BACKGROUND: Aspartic acid to glycine substitution (D222G) of haemagglutinin subunit (HA1) was associated with adverse outcomes in 2009 pandemic influenza A (H1N1) infections. OBJECTIVES: To characterize the virological profile and antiviral response of patients infected with the HA1 D222G mutant. STUDY DESIGN: Sixty-three adults admitted for pandemic influenza in Hong Kong were tested for D222G mutation by direct sequencing. Nasopharyngeal viral concentration on presentation was measured by real-time PCR to evaluate shedding from the upper respiratory tract. Serial upper and lower respiratory tract specimens were monitored to determine preferential tropism and document virological response to treatment. RESULTS: The frequency of D222G infection was 17.4% among cases with severe pneumonia, and 26.7% among cases requiring intensive care. Altogether, four sporadic D222G cases spread across the first and second waves in Hong Kong were detected. A significant association between D222G infection with severe pneumonia (100% vs. 32.2%, P=0.015) and intensive care admission (100% vs. 18.6%, P=0.002) was observed. D222G was associated with lower concentrations of virus in the upper respiratory tract compared to wildtype, but persisted in the lower respiratory tract at high concentrations, despite clearance from the upper respiratory tract following antiviral treatment. CONCLUSIONS: These observations suggest that D222G can arise de novo, sheds less virus from the upper respiratory tract and may be less transmissible, but more pneumotropic and more resistant to antiviral treatment. D222G is associated with a higher chance of developing critical disease. Lower respiratory tract specimen is needed for a reliable detection of this mutant.
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Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/virologia , Mutação , Adulto , Idoso , Idoso de 80 Anos ou mais , Substituição de Aminoácidos , Estudos de Coortes , Feminino , Hong Kong/epidemiologia , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/epidemiologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia/virologia , Sistema Respiratório/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Adulto JovemRESUMO
In early 2008, a sudden increase in oseltamivir (Tamiflu)-resistant influenza A H1N1 viruses was reported from several European countries. This resistant virus has spread globally and accounted for more than 95% of H1N1 viruses isolated in the following influenza season. A continuous close monitoring on the prevalence of this resistant virus is necessary to rationalize the choice of antiviral agents. The resistance of this novel strain to oseltamivir is conferred by an amino acid substitution from histidine to tyrosine at position 275 (H275Y) of the neuraminidase protein. This study developed and evaluated allele-specific conventional reverse-transcription polymerase chain reaction (cRT-PCR) assays to provide a simple, rapid, and low-cost option for discriminating oseltamivir-resistant influenza A H1N1 (H275Y) mutant from wild-type viruses. The evaluation was based on 90 nasopharyngeal aspirate specimens collected before, during the initial phase and at the peak of emergence of resistance. Thirty-six (40%) of these specimens were H275Y mutant, whereas the other 54 (60%) were wild-type viruses as confirmed by sequencing of the neuraminidase gene. When applied directly on the 90 nasopharyngeal aspirate specimens, the allele-specific cRT-PCR assays achieved an unequivocal discrimination for 82 (91%) specimens. Further improvement in performance is expected when applied to cell culture isolates with a higher viral titer. These allele-specific cRT-PCR assays can be a simple, low-cost option for large-scale screening of influenza isolates.
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Substituição de Aminoácidos/genética , Farmacorresistência Viral , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Neuraminidase/genética , Oseltamivir/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Proteínas Virais/genética , Virologia/métodos , Antivirais/farmacologia , Humanos , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/virologia , Programas de Rastreamento/métodos , Dados de Sequência Molecular , Nasofaringe/virologia , RNA Viral/genética , Sensibilidade e Especificidade , Análise de Sequência de DNARESUMO
Human infection with the novel pandemic influenza A (H1N1) virus was first identified in April 2009. Two months later, the World Health Organization (WHO) had raised the pandemic level to phase 6. Rapid case identification is essential for prompt patient management and public health actions. This study developed real-time and conventional reverse transcription-polymerase chain reaction (rRT-PCR and cRT-PCR) assays for pandemic H1N1 detection, and compared their sensitivities with protocols developed by WHO reference centres. Altogether, three rRT-PCR and one cRT-PCR targeting the matrix gene for universal detection of influenza A; three rRT-PCR, one cRT-PCR targeting the hemagglutinin (HA) gene for specific detection of pandemic H1N1; and one multiplex cRT-PCR for differentiating co-circulating seasonal H1N1, H3N2, and pandemic H1N1 were examined. The lower detection limit ranged from 1.252 to 125.2 copy equivalents. In general, rRT-PCR assays were more sensitive than cRT-PCR assays. All assays showed 100% sensitivity for "optimal" specimens (nasopharyngeal samples collected within 4 days after illness onset). For the other 36 samples, cRT-PCR assays were less sensitive except that the new Protocol I-cRT-pdmH1 still retained 100% sensitivity. The new Protocol F-rRT-PCR-pdmH1 was the only pandemic virus-specific rRT-PCR assay with 100% sensitivity across all specimen categories. In conclusion, rRT-PCR assays are 10-fold more sensitive than cRT-PCR assays. The newly developed cRT-PCR assay targeting the HA gene allows rapid, specific, and sensitive screening of this novel agent, which can serve as an alternative for laboratories where a real-time PCR machine is not available.
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Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/diagnóstico , Influenza Humana/virologia , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Hemaglutininas Virais/genética , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Nasofaringe/virologia , Sensibilidade e Especificidade , Proteínas da Matriz Viral/genéticaRESUMO
Human coronavirus NL63 (HCoV-NL63) has been found in children presenting with respiratory tract infections (RTIs). However, the epidemiology and clinical course of this newly identified virus have not been fully elucidated. This study investigated the epidemiology, seasonality, and clinical features of HCoV-NL63 in Hong Kong children. This study consisted of two cohorts of children hospitalized in a university-affiliated teaching hospital. In the 12-month retrospective part of the study, reverse transcription-PCR was used to detect HCoVs in nasopharyngeal aspirates (NPAs). Positive samples were sequenced to confirm the identity of the virus and to determine its phylogenetic relationship with the HCoV-NL63 strains found elsewhere. The second part covered a subsequent 12-month period in which patients were prospectively recruited. Altogether, 1,981 and 1,001 NPA specimens were studied in 2005-2006 and 2006-2007, respectively. Seventy-four (2.5%) HCoV isolates were identified and consisted of 17 (0.6%) HCoV-NL63 isolates, 37 (1.2%) HCoV-OC43 isolates, 14 (0.5%) HCoV-HKU1 isolates, and 6 (0.2%) HCoV-229E isolates. HCoV-NL63 infection was more common in 2006-2007 than 2005-2006 (1.2% and 0.3%, respectively; P = 0.006). From 2005 to 2007, the peak season for HCoV-NL63 infection was in September-October, which was earlier than the peak for HCoV-OC43 infections (December-January). HCoV-NL63-infected patients were younger and more likely to have croup, febrile convulsions, and acute gastroenteritis. The majority of local HCoV-NL63 isolates were phylogenetically closely related to those found in Belgium and The Netherlands. In conclusion, HCoV-NL63 is an important yet uncommon virus among our hospitalized children with acute RTIs.
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Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/patologia , Coronavirus/classificação , Coronavirus/isolamento & purificação , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/patologia , Fatores Etários , Criança , Pré-Escolar , Análise por Conglomerados , Estudos de Coortes , Coronavirus/genética , Infecções por Coronavirus/virologia , Feminino , Hong Kong/epidemiologia , Hospitais de Ensino , Humanos , Pacientes Internados , Masculino , Dados de Sequência Molecular , Nasofaringe/virologia , Filogenia , RNA Viral/genética , Infecções Respiratórias/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estações do Ano , Análise de Sequência de DNA , Homologia de SequênciaRESUMO
Influenza seasons appear consistently in the temperate regions, but are more variable in tropical/subtropical regions. The determinant for such variation remains poorly understood. This study documented the activity of influenza over a 10-year period in Hong Kong; examining its association with changes in temperature and relative humidity. The two types of influenza exhibited different correlations with meteorological variations. Influenza A showed two seasonal peaks occurring respectively in winter/spring and summer months in most years. Influenza B showed a clear winter/spring peak, but its activity during summer months was more variable. Cold and humid conditions were associated with a higher activity of both influenza A and B. In contrast, hot and humid conditions were associated with a higher activity of influenza A, but were associated with only a moderate, less consistent increase in the activity of influenza B. A trend of increase in the magnitude of summer peaks of influenza A, but not influenza B, was observed. A hypothetical 2 degrees C rise in temperature would decrease the proportion of favorable days for influenza A in December-April from 78% to 57%, but an increase from 58% to 71% in May-November; with a similar effect (from 83% to 62%) for influenza B during December-April, but a modest change (from 17% to 18%) during May-November. The presence of two seasonal peaks of influenza annually emphasizes the need to evaluate the duration of protective immunity offered by vaccination. Further study on the effects of climate change and global warming on the activity of influenza is warranted.
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Vírus da Influenza A/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/virologia , Estações do Ano , Clima , Hong Kong/epidemiologia , Humanos , Umidade , TemperaturaRESUMO
BACKGROUND: The goal of this study was to characterize viral loads and factors affecting viral clearance in persons with severe influenza. METHODS: This was a 1-year prospective, observational study involving consecutive adults hospitalized with influenza. Nasal and throat swabs were collected at presentation, then daily until 1 week after symptom onset. Real-time reverse-transcriptase polymerase chain reaction to determine viral RNA concentration and virus isolation were performed. Viral RNA concentration was analyzed using multiple linear or logistic regressions or mixed-effect models. RESULTS: One hundred forty-seven inpatients with influenza A (H3N2) infection were studied (mean age+/-standard deviation, 72+/-16 years). Viral RNA concentration at presentation positively correlated with symptom scores and was significantly higher than that among time-matched outpatients (control subjects). Patients with major comorbidities had high viral RNA concentration even when presenting>2 days after symptom onset (mean+/-standard deviation, 5.06+/-1.85 vs 3.62+/-2.13 log10 copies/mL; P=.005; beta, +0.86 [95% confidence interval, +0.03 to +1.68]). Viral RNA concentration demonstrated a nonlinear decrease with time; 26% of oseltamivir-treated and 57% of untreated patients had RNA detected at 1 week after symptom onset. Oseltamivir started on or before symptom day 4 was independently associated with an accelerated decrease in viral RNA concentration (mean beta [standard error], -1.19 [0.43] and -0.68 [0.33] log10 copies/mL for patients treated on day 1 and days 2-3, respectively; P<.05) and viral RNA clearance at 1 week (odds ratio, 0.10 [95% confidence interval, 0.03-0.35] and 0.30 [0.10-0.90] for patients treated on day 1-2 and day 3-4, respectively). Conversely, major comorbidities and systemic corticosteroid use for asthma or chronic obstructive pulmonary disease exacerbations were associated with slower viral clearance. Viral RNA clearance was associated with a shorter hospital stay (7.0 vs 13.5 days; P=.001). CONCLUSION: Patients hospitalized with severe influenza have more active and prolonged viral replication. Weakened host defenses slow viral clearance, whereas antivirals started within the first 4 days of illness enhance viral clearance.
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Vírus da Influenza A Subtipo H3N2 , Influenza Humana/virologia , Carga Viral , Eliminação de Partículas Virais , Idoso , Envelhecimento , Antivirais/uso terapêutico , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Oseltamivir/uso terapêutico , Estudos Prospectivos , Fatores de TempoRESUMO
Most acute cases of infection with hepatitis E virus (HEV) in Hong Kong were autochthonous, sporadic, and occurred in older adults. All except 1 isolate belonged to genotype 4; most were phylogenetically related to swine isolates. The epidemiology is similar to that in industrialized countries, where zoonosis is the major source of HEV infection in humans.
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Variação Genética , Vírus da Hepatite E/classificação , Vírus da Hepatite E/genética , Hepatite E/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Genótipo , Hepatite E/virologia , Vírus da Hepatite E/isolamento & purificação , Hong Kong/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Prevalência , Análise de Sequência de DNA , Adulto JovemRESUMO
UNLABELLED: HCC is a common cause of morbidity and mortality. For patients who are not candidates for curative surgery, systemic chemotherapy is one of the standard treatments. In parts of China and the Far East, over 80% of HCC patients have chronic HBV infection. In this study, we aimed to assess the relationship between pre-chemotherapy HBV viral load and the survival of HCC patients. HBV infection status was determined prior to chemotherapy in 188 patients, 170 of whom had evidence of HBV chronic infection/exposure (160 hepatitis B surface antigen [HBsAg]-positive, 10 HBsAg-negative/hepatitis B core antibody-positive). Of these, 125 had pretreatment HBV DNA levels determined via real-time PCR. Virological data were analyzed using conventional clinical variables to identify factors that influenced survival. Multivariate analysis revealed that high total bilirubin (P = 0.0016; hazard ratio = 1.040 per 1 muM increase; 95% CI 1.015-1.065), HCV infection (P = 0.0095; hazard ratio = 6.955; 95% CI 1.606-30.129), and high HBV DNA level (P = 0.0217; hazard ratio = 1.650; 95% CI 1.076-2.531) affected survival significantly. Exploratory analysis revealed that high levels of pretreatment HBV DNA had a significantly higher incidence of severe hepatitis during chemotherapy. CONCLUSION: For HCC patients with HBV chronic infection/exposure, a high viral load prior to treatment is an adverse factor for survival and may be associated with a higher incidence of severe hepatitis during chemotherapy. Future strategies to improve the prognosis of HCC patients undergoing chemotherapy should consider supportive therapy that incorporates antiviral therapies to reduce HBV viral load.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/mortalidade , Hepatite B Crônica/mortalidade , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/mortalidade , Carga Viral , Adulto , Idoso , Antibióticos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/administração & dosagem , Antivirais/farmacologia , Carcinoma Hepatocelular/virologia , Cisplatino/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/farmacologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Proteínas Recombinantes , Análise de SobrevidaRESUMO
Ethanolic extract of Phyllanthus nanus (P. nanus) treatment exhibited potent antiviral activity against Hepatitis B virus (HBV). The effects of these extracts on HBV in the HBV genome integrated cell lines--Alexander cells and HepG2 2.2.15 cells were examined. Experimental results showed that the ethanolic extract of P. nanus produced suppressive effect on HBsAg secretion and HBsAg mRNA expression. The extract also inhibited HBV replication as measured by HBV DNA level in vitro. In addition, using a duck HBV (DHBV) primary culture model, the P. nanus ethanolic extract suppressed viral replication of DHBV in DHBV infected primary duck hepatocytes. The gene expression pattern in Alexander cells that had been treated with the ethanolic extract of P. nanus was also revealed by microarray techniques. The microarray results indicated that there was up-regulation of expression of several genes, including annexin A7 (Axn7). The subcellular localization of Axn7 and anti-HBV effect of Axn7 over-expression in Alexander cells were also investigated. Results showed that expression of Axn7-GFP fusion protein are localized around the secretory vesicles and could cause a decrease in HBsAg secretion in Alexander cells. Axn7 protein might play an important role in the medicinal effect of the active principle(s) of P. nanus.