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1.
Arch Virol ; 163(9): 2349-2358, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29736671

RESUMO

Seasonal influenza virus remains a common cause of mortality despite the use of neuraminidase inhibitors. This study evaluated the efficacy of a triple combination of zanamivir, clarithromycin and flufenamic acid (FFA) in the treatment of influenza virus A(H1N1) infection. An in vitro cell protection assay and a multiple-cycle growth assay showed that the antiviral activity of zanamivir was enhanced when combined with clarithromycin or FFA. A mouse challenge model was used here for the evaluation of the in vivo efficacy of the triple combination treatment. We found that mice receiving the triple combination of FFA, zanamivir, and clarithromycin had a significantly better survival rate than those receiving the double combination of zanamivir and clarithromycin (88% versus 44%, P = 0.0083) or zanamivir monotherapy (88% versus 26%, P = 0.0002). Mice in the FFA-zanamivir-clarithromycin triple combination group also exhibited significantly less body weight loss than those in the zanamivir-clarithromycin double combination group. There was no significant difference in the lung viral titers among the different groups from day 2 to day 6 postinfection. However, the levels of IL-1ß, TNF-α and RANTES in the FFA-zanamivir-clarithromycin triple combination group were significantly lower than those in the zanamivir-clarithromycin double combination group, zanamivir monotherapy group, or solvent group on day 2 postinfection. Our findings showed that the FFA-zanamivir-clarithromycin triple combination improved the inflammatory markers and survival of severe influenza A(H1N1) infection in mice.


Assuntos
Antivirais/administração & dosagem , Claritromicina/administração & dosagem , Ácido Flufenâmico/administração & dosagem , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Influenza Humana/tratamento farmacológico , Influenza Humana/mortalidade , Zanamivir/administração & dosagem , Animais , Aprovação de Drogas/legislação & jurisprudência , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/metabolismo , Influenza Humana/virologia , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Pulmão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Estados Unidos , United States Food and Drug Administration
2.
PLoS One ; 9(9): e107966, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25232731

RESUMO

BACKGROUND: Human infection caused by the avian influenza A H7N9 virus has a case-fatality rate of over 30%. Systematic study of the pathogenesis of avian H7N9 isolate and effective therapeutic strategies are needed. METHODS: BALB/c mice were inoculated intranasally with an H7N9 virus isolated from a chicken in a wet market epidemiologically linked to a fatal human case, (A/chicken/Zhejiang/DTID-ZJU01/2013 [CK1]), and with an H7N9 virus isolated from a human (A/Anhui/01/2013 [AH1]). The pulmonary viral loads, cytokine/chemokine profiles and histopathological changes of the infected mice were compared. The therapeutic efficacy of a non-steroidal anti-inflammatory drug (NSAID), celecoxib, was assessed. RESULTS: Without prior adaptation, intranasal inoculation of 106 plaque forming units (PFUs) of CK1 caused a mortality rate of 82% (14/17) in mice. Viral nucleoprotein and RNA expression were limited to the respiratory system and no viral RNA could be detected from brain, liver and kidney tissues. CK1 caused heavy alveolar inflammatory exudation and pulmonary hemorrhage, associated with high pulmonary levels of proinflammatory cytokines. In the mouse lung cell line LA-4, CK1 also induced high levels of interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2) mRNA. Administration of the antiviral zanamivir did not significantly improve survival in mice infected with CK1, but co-administration of the non-steroidal anti-inflammatory drug (NSAID) celecoxib in combination with zanamivir improved survival and lung pathology. CONCLUSIONS: Our findings suggested that H7N9 viruses isolated from chicken without preceding trans-species adaptation can cause lethal mammalian pulmonary infection. The severe proinflammatory responses might be a factor contributing to the mortality. Treatment with combination of antiviral and NSAID could ameliorate pulmonary inflammation and may improve survival.


Assuntos
Antivirais/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Subtipo H7N9 do Vírus da Influenza A/fisiologia , Pneumonia Viral/tratamento farmacológico , Zanamivir/farmacologia , Adaptação Fisiológica/imunologia , Animais , Antivirais/uso terapêutico , Linhagem Celular , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Citocinas/metabolismo , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Humanos , Subtipo H7N9 do Vírus da Influenza A/efeitos dos fármacos , Subtipo H7N9 do Vírus da Influenza A/imunologia , Pulmão/patologia , Pulmão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Replicação Viral , Zanamivir/uso terapêutico
3.
J Clin Microbiol ; 50(5): 1571-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22357507

RESUMO

We studied the clinical and epidemiological characteristics of Klebsiella oxytoca-associated diarrhea in hospitalized patients in Hong Kong. Between 1 November 2009 and 30 April 2011, all inositol-fermenting colonies found on Simmons citrate agar supplemented with inositol, tryptophan, and bile salts (SCITB agar) used for the culturing of diarrheal stool samples were screened by a spot indole test for K. oxytoca. The overall sensitivity of SCITB agar plus the spot indole test (93.3%) for the detection of K. oxytoca in stool samples was superior to that of MacConkey agar (63.3%), while the specificities were 100% and 60.4%, respectively. The former achieved a 23-fold reduction in the workload and cost of subsequent standard biochemical identifications. Cytotoxin production and the clonality of K. oxytoca were determined by a cell culture cytotoxicity neutralization assay using HEp-2 cells and pulsed-field gel electrophoresis (PFGE), respectively. Of 5,581 stool samples from 3,537 patients, K. oxytoca was cultured from 117/5,581 (2.1%) stool samples from 104/3,537 (2.9%) patients. Seventy-six of 104 (73.1%) patients with K. oxytoca had no copathogens in their diarrheal stool samples. Twenty-four (31.6%) of 76 patients carried cytotoxin-producing strains, which were significantly associated with antibiotic therapy after hospital admission (50% versus 21.2%; P = 0.01). Health care-associated diarrhea was found in 44 (42%) of 104 patients with K. oxytoca, but there was no epidemiological linkage suggestive of a nosocomial outbreak, and PFGE showed a diverse pattern. None of the patients with cytotoxin-producing K. oxytoca developed antibiotic-associated hemorrhagic colitis, suggesting that K. oxytoca can cause a mild disease manifesting as uncomplicated antibiotic-associated diarrhea with winter seasonality.


Assuntos
Técnicas Bacteriológicas/métodos , Meios de Cultura/química , Diarreia/epidemiologia , Diarreia/microbiologia , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Klebsiella oxytoca/isolamento & purificação , Adolescente , Adulto , Ágar , Idoso , Idoso de 80 Anos ou mais , Ácidos e Sais Biliares/metabolismo , Linhagem Celular , Criança , Pré-Escolar , Ácido Cítrico/metabolismo , Eletroforese em Gel de Campo Pulsado , Hepatócitos/microbiologia , Hong Kong/epidemiologia , Hospitalização , Humanos , Lactente , Inositol/metabolismo , Klebsiella oxytoca/classificação , Klebsiella oxytoca/genética , Klebsiella oxytoca/patogenicidade , Masculino , Pessoa de Meia-Idade , Tipagem Molecular , Sensibilidade e Especificidade , Triptofano/metabolismo , Adulto Jovem
4.
J Gastroenterol Hepatol ; 24(12): 1810-6, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20002940

RESUMO

The prevalence of colorectal cancer is increasing in Asia. However, the age-standardized rate has reached a plateau in some countries. Some studies have shown a male predominance difference and increasing risk in the elderly, but not in the younger population. 'Right shifting' of colorectal cancer, not accountable by difference in age or the indications for endoscopic examination, has also been noted. Westernized diet is associated with colorectal cancer, but controversy remains on how it causes colorectal cancer. Alcohol consumption, obesity, diabetes mellitus, consumption of red and processed meat and cigarette smoking are linked to bowel cancer epidemiologically. Only high dietary calcium has a consistent negative (or 'protective') effect. The efficacy of fish oil, vitamin D, soy, phytoestrogens, folate, methionine, riboflavin and vitamin B6 has not been established. Aspirin and non-steroidal anti-inflammatory drugs use decrease risk of colorectal cancer after 5-10 years of use. There is no evidence for a detrimental effect of proton pump inhibitors or benefit of statins in colorectal cancer. In conclusion, there is a rising trend and prevalence of colorectal cancer in Asia. Dietary modification or supplementation may not be effective in preventing colorectal cancer. Surveillance of colorectal cancer in high-risk groups, according to current recommendation, is probably most effective.


Assuntos
Neoplasias Colorretais/epidemiologia , Distribuição por Idade , Anticarcinógenos/administração & dosagem , Ásia/epidemiologia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/prevenção & controle , Dieta/efeitos adversos , Feminino , Humanos , Masculino , Programas de Rastreamento/métodos , Prevalência , Medição de Risco , Fatores de Risco , Comportamento de Redução do Risco , Distribuição por Sexo , Fatores de Tempo
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