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2.
Exp Physiol ; 100(10): 1107-17, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26206681

RESUMO

NEW FINDINGS: What is the central question of this study? This study addresses the following two central questions. (i) What is the impact of vascular deconditioning after spinal cord injury (SCI) on shear rate patterns and endothelial function? (ii) What is the impact of acutely altered shear rate on endothelial function in both SCI and able-bodied control subjects? What is the main finding and its importance? Two main findings in the present study were as follows: (i) reduced superficial femoral artery endothelial function in the SCI group; and (ii) acutely altered shear rate decreased endothelial function in both SCI and able-bodied control subjects. These findings may shed some light on future interventions taking into account these regulatory mechanisms. Spinal cord injury (SCI) induces vascular deconditioning below the level of the lesion and disrupts sympathetic innervation of blood vessels. It is unclear how these changes affect shear rate (SR) profiles and endothelial function when compared with able-bodied (AB) persons. Recent evidence suggests that periods of increased retrograde SR are associated with acute decreases in endothelial function, but is unknown how modified SR patterns influence sublesional vasculature in SCI. The present study examined the acute and chronic effects of altered SR patterns and oscillatory shear index on endothelial function via relative flow-mediated dilatation (FMD%) in both the brachial and superficial femoral arteries (BA and SFA, respectively) of eight individuals with SCI and eight matched AB control subjects. Baseline BA SR patterns and FMD% were similar between groups, while SFA anterograde SR was higher (P < 0.01) and FMD% lower (P = 0.04) in SCI versus AB subjects. Shear rate patterns were then acutely altered through the BA and SFA using a subsystolic cuff-inflation model. Bilateral FMD assessments were conducted before and after 30 min of unilateral inflation of a forearm or thigh blood pressure cuff to 75 mmHg. Cuff inflation resulted in concomitant increases in both anterograde (P < 0.05) and retrograde SR (P < 0.05), as well as acute decreases in FMD% (P < 0.05) in the BA and SFA in both groups. These results highlight that brief manipulation of SR patterns can acutely impair FMD% in conditions of both normal and altered sympathetic innervation and arterial remodelling. This information is crucial when designing strategies to combat impaired vascular function in both healthy and clinical populations.


Assuntos
Artéria Braquial/fisiopatologia , Endotélio Vascular/fisiopatologia , Artéria Femoral/fisiopatologia , Extremidade Inferior/irrigação sanguínea , Traumatismos da Medula Espinal/fisiopatologia , Extremidade Superior/irrigação sanguínea , Vasodilatação , Adaptação Fisiológica , Adulto , Velocidade do Fluxo Sanguíneo , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/inervação , Estudos de Casos e Controles , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/inervação , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Traumatismos da Medula Espinal/diagnóstico , Estresse Mecânico , Fatores de Tempo , Ultrassonografia Doppler de Pulso
3.
Clin Pharmacol Ther ; 95(1): 78-88, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24126682

RESUMO

Chronic hepatitis C virus (HCV) infection afflicts a reported 170 million people worldwide and is often complicated by cirrhosis and hepatocellular carcinoma. Morbidity and mortality are decreased with the successful treatment of chronic HCV infection. The current standard of care in the treatment for genotype 1 chronic HCV is pegylated interferon (IFN)-alfa, termed PEG, and ribavirin (RBV) in conjunction with a protease inhibitor, either telaprevir or boceprevir, which results in 67-75% sustained viral response rates. Increased understanding of the HCV has allowed further development of new direct-acting antiviral (DAA) agents against the HCV and has also allowed the development of IFN-free oral treatment regimens. We anticipate the approval in late 2013 of the first nucleotide polymerase inhibitor regimen with RBV alone for genotypes 2/3 and in combination with a 12-week regimen of PEG+RBV for genotypes 1, 4, 5, and 6. Most of the promising new DAA regimens are discussed herein.


Assuntos
Antivirais/uso terapêutico , Descoberta de Drogas/tendências , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Animais , Ensaios Clínicos como Assunto/métodos , Hepacivirus/genética , Hepatite C Crônica/diagnóstico , Humanos , Ribavirina/uso terapêutico
4.
Ann Oncol ; 23(1): 72-77, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21464154

RESUMO

BACKGROUND: This open-label phase III study assessed the addition of Toll-like receptor 9-activating oligodeoxynucleotide PF-3512676 to gemcitabine/cisplatin chemotherapy in patients with non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Chemotherapy-naive patients with stage IIIB or IV NSCLC were randomized (1:1) to receive six or fewer 3-week cycles of i.v. gemcitabine (1250 mg/m2 on days 1 and 8) and cisplatin alone (75 mg/m2 on day 1, control arm) or combined with s.c. PF-3512676 0.2 mg/kg on days 8 and 15 of each chemotherapy cycle and weekly thereafter until progression or unacceptable toxicity (experimental arm). No crossover was planned. The primary end point was overall survival (OS). RESULTS: A total of 839 patients were randomized. Baseline demographics were well balanced. Median OS (11.0 versus 10.7 months; P=0.98) and median progression-free survival (PFS) (both 5.1 months) were similar between groups. Grade≥3 hematologic adverse events (AEs), injection-site reactions, and influenza-like symptoms were more frequently reported among patients receiving PF-3512676. At the first-interim analysis, the Data Safety Monitoring Committee recommended study discontinuation. Administration of PF-3512676 was halted based on efficacy futility and increased grade≥3 AEs (experimental arm). CONCLUSIONS: Addition of PF-3512676 to gemcitabine/cisplatin chemotherapy did not improve OS or PFS but did increase toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Oligodesoxirribonucleotídeos/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Oligodesoxirribonucleotídeos/efeitos adversos , Modelos de Riscos Proporcionais , Gencitabina
5.
Aliment Pharmacol Ther ; 34(1): 11-20, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21539586

RESUMO

BACKGROUND: Drug-induced liver injury (DILI) is a significant cause of morbidity and mortality accounting for at least 13% of acute liver failure cases in the US. It is the leading cause of acute liver failure among patients referred for liver transplantation and the most common reason that drugs in development do not obtain FDA approval. The incidence of DILI has been reported to be one in 10,000 to one in 100,000 patients; however, the actual incidence is probably higher due in part to the difficulty of diagnosis. AIM: To present a review of the current literature on DILI with a focus on its pathophysiology and evolving diagnostic modalities. METHODS: A PubMed literature search was conducted using the terms 'drug induced liver injury', 'pathophysiology', 'causality', 'diagnosis', 'toxicogenomics' and 'pharmacogenetics'. RESULTS: Drug-induced liver injury is an area of ongoing research. From the time it was first recognised, our understanding of the pathophysiology, its classification, diagnosis and reporting by established national networks continues to challenge and evolve. Metabonomics, pharmacogenetics, proteomics and transcriptomics are more recent areas of study that have been applied to further the understanding of DILI. CONCLUSIONS: Despite recent advances in our understanding of drug-induced liver injury, many aspects of its pathophysiology and clinical impact remain unclear. In addition, genomic-based studies are evolving concepts, which undoubtedly continue to contribute to our understanding of the underlying mechanisms of drug-induced liver injury.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Falência Hepática/etiologia , Fígado/patologia , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/genética , Humanos , Falência Hepática/induzido quimicamente , Falência Hepática/diagnóstico , Farmacogenética
6.
Br J Cancer ; 104(1): 208-13, 2011 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-21102581

RESUMO

BACKGROUND: Few epidemiological studies have explored the associations between occupational exposures and lung cancer in lifelong nonsmoking men. METHODS: We obtained lifetime occupational history and other relevant information for 132 newly diagnosed lung cancer cases among nonsmoking Chinese men and 536 nonsmoking community referents. Unconditional multiple logistic regression analysis was performed to estimate the odds ratio (OR) of lung cancer for specific occupational exposures. RESULTS: Significantly increased lung cancer risk was found for nonsmoking workers occupationally exposed to silica dust (OR=2.58, 95% confidence interval (CI): 1.11, 6.01), diesel exhaust (OR=3.47, 95% CI: 1.08, 11.14), spray painting (OR=2.81, 95% CI: 1.14, 6.93), and nonspray painting work (OR=2.36, 95% CI: 1.04, 5.37). Silica dust exposure was associated with a significantly increased risk of adenocarcinoma (OR=2.91, 95% CI: 1.10, 7.68). We observed a positive gradient of all lung cancers and of adenocarcinoma with duration of employment for workers exposed to silica dust and spray painting. CONCLUSION: This study found an increased risk of lung cancer among nonsmoking Chinese men occupationally exposed to silica dust, diesel exhaust, and painting work.


Assuntos
Neoplasias Pulmonares/etiologia , Doenças Profissionais/etiologia , Exposição Ocupacional/efeitos adversos , Pintura/efeitos adversos , Dióxido de Silício/efeitos adversos , Emissões de Veículos , Adenocarcinoma/epidemiologia , Adenocarcinoma/etiologia , Adenocarcinoma de Pulmão , Adulto , Idoso , Estudos de Casos e Controles , China/epidemiologia , Poeira , Humanos , Incidência , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/epidemiologia , Razão de Chances , Prognóstico , Fatores de Risco
7.
Br J Cancer ; 102(12): 1731-5, 2010 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-20502455

RESUMO

BACKGROUND: Lung cancer is known as the top cancer killer in most developed countries. However, there is currently no promising diagnostic or prognostic biomarker for lung cancer. This study aims to discover non-invasive differential markers in the serum of lung cancer patients, to determine the protein identity of the candidate biomarker(s), and to investigate any clinical implication of the biomarker(s) concerned. METHODS: Blood specimens were collected from 154 pre-operative patients with lung cancer and 35 healthy blood donors with no evidence of lung cancer. Fractionated serum samples were processed by surface-enhanced laser desorption/ionisation time-of-flight mass spectrometry (MS). Candidate biomarker was identified using sodium dodecyl sulphate polyacrylamide gel electrophoresis and tryptic digestion followed by tandem MS fragmentation analysis, which was subsequently validated with immunoassay. RESULTS: A differential protein with m/z 11.6 kDa was detected and identified as an isoform of human serum amyloid A (SAA). It was significantly increased by 1822% in lung cancer patients when compared with the healthy controls, which gave an area under the receiver operator characteristic curve of 0.88. In addition, the protein was also significantly elevated by 77% in lung cancer patients with survival <5 years when compared with patients with survival > or =5 years. CONCLUSION: There are several functions of the SAA protein, described in the context of inflammation, that are compatible with the mechanism of tumour invasion and metastasis. Our study not only detected increased SAA level in the serum of lung cancer patients but also identified that elevated SAA level may be a non-invasive biomarker useful for the prediction of lung cancer prognosis.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Pulmonares/sangue , Proteína Amiloide A Sérica/metabolismo , Idoso , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico
8.
Ann Oncol ; 21(2): 217-222, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20110292

RESUMO

BACKGROUND: Identification of appropriate markers for predicting clinical benefit with erlotinib in non-small-cell lung cancer (NSCLC) may be able to guide patient selection for treatment. This open-label, multicentre, phase II trial aimed to identify genes with potential use as biomarkers for clinical benefit from erlotinib therapy. METHODS: Adults with stage IIIb/IV NSCLC in whom one or more chemotherapy regimen had failed were treated with erlotinib (150 mg/day). Tumour biopsies were analysed using gene expression profiling with Affymetrix GeneChip microarrays. Differentially expressed genes were verified using quantitative RT-PCR (qRT-PCR). RESULTS: A total of 264 patients were enrolled in the study. Gene expression profiles found no statistically significant differentially expressed genes between patients with and without clinical benefit. In an exploratory analysis in responding versus nonresponding patients, three genes on chromosome 7 were expressed at higher levels in the responding group [epidermal growth factor receptor (EGFR), phosphoserine phosphatase (PSPH) and Rap guanine nucleotide exchange factor 5 (RAPGEF5)]. Independent quantification using qRT-PCR validated the association between EGFR and PSPH overexpression, but not RAPGEF5 overexpression, and clinical outcome. CONCLUSIONS: This study supports the use of erlotinib as an alternative to chemotherapy for patients with relapsed advanced NSCLC. Genetic amplification of the EGFR region of chromosome 7 may be associated with response to erlotinib therapy.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Perfilação da Expressão Gênica , Neoplasias Pulmonares/tratamento farmacológico , Quinazolinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Biomarcadores Farmacológicos/análise , Biomarcadores Farmacológicos/metabolismo , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Intervalo Livre de Doença , Cloridrato de Erlotinib , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Quinazolinas/efeitos adversos
9.
Ann Oncol ; 20(4): 746-51, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19150939

RESUMO

BACKGROUND: We conducted this case-control study to evaluate smoking effect on lung cancer conditional on the level of exposure to cooking emissions and to explore whether there is a joint effect of these two risk factors. SUBJECTS AND METHODS: We selected 279 newly diagnosed primary lung cancer cases and 322 community controls from Hong Kong females, frequency matched by age group, and collected relevant data. We applied logistic regression to estimate lung cancer risk related to smoking and cooking fume exposure, expressed as total cooking dish-years, while adjusting for various potential confounding factors. RESULTS: Current smoking was associated with four-fold increased risk, and ex-smoking with two-fold risk, which was not much influenced by cooking dish-years. No increased risk was observed in environmental tobacco smoking. Increasing intakes of yellow/orange vegetables and multivitamins were significant protective factors in all models. In the analysis of joint effect, the combination of smoking and cooking dish-years tended to have a greater risk than exposure to cooking fumes alone. There was a dose-response gradient with total dish-years in nonsmokers, but not in smokers. Smoking was more strongly associated with nonadenocarcinoma, whereas exposure to cooking fumes appeared to be related to both adenocarcinoma and nonadenocarcinoma. CONCLUSION: We confirmed the important roles of smoking and cooking emissions in lung cancer risk among the women. These two major risk factors appeared to act independently.


Assuntos
Poluição do Ar em Ambientes Fechados , Culinária , Neoplasias Pulmonares/etiologia , Fumar/efeitos adversos , Adulto , Idoso , Estudos de Casos e Controles , Fatores de Confusão Epidemiológicos , Feminino , Hong Kong/epidemiologia , Humanos , Neoplasias Pulmonares/epidemiologia , Pessoa de Meia-Idade , Fatores de Risco
10.
Clin Oncol (R Coll Radiol) ; 16(4): 269-76, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15214651

RESUMO

AIMS: To evaluate the current UICC/AJCC Staging System for nasopharyngeal carcinoma and to search for ways of improving the system. MATERIALS AND METHODS: This is a retrospective analysis of 2687 consecutive patients treated in five public centres in Hong Kong during the period 1996-2000. All patients were staged by computed tomography, magnetic resonance imaging, or both. The prognostic significance of the current stage assignment on various aspects of tumour control was evaluated. RESULTS: T-category, N-category and stage-group were all significant prognostic factors for major end points (P < 0.01). However, the distinction of prognosis between Stage I and II was insignificant (5-year cancer-specific survival being 92% vs 95%; P = 0.13). Multivariate analyses (corrected for age and sex) revealed lack of significance between T2a and T1 in hazards of local and distant failures, N3a and N2 in distant failure and subgroups of T1-2N0 in cancer-specific deaths. Corresponding down-staging of T2a to T1, N3a to N2, and subgroup T2N0 to stage I, resulted in more even and orderly increase in the hazard ratio of cancer-specific deaths (from 1 for stage I to 1.98 for II, 3.5 for III, 6.08 for IVA and 8.62 for IVB), better hazard consistency among subgroups of the same stage and more balanced stage distribution. CONCLUSIONS: The current UICC/AJCC Staging System could be further improved by the modifications suggested; validation of the current proposal by external data is urgently awaited.


Assuntos
Neoplasias Nasofaríngeas/epidemiologia , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Hong Kong/epidemiologia , Humanos , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/mortalidade , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida
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