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1.
Hong Kong Med J ; 29(5): 412-420, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37794613

RESUMO

INTRODUCTION: Telemedicine services worldwide have experienced unprecedented growth since the early days of the coronavirus disease 2019 (COVID-19) pandemic. Multiple studies have shown that telemedicine is an effective alternative to conventional in-person patient care. This study explored the public perception of telemedicine in Hong Kong, specifically among older adults who are most vulnerable to COVID-19. METHODS: Medical students from The Chinese University of Hong Kong conducted in-person surveys of older adults aged ≥60 years. Each survey collected socio-demographic information, medical history, and concerns regarding telemedicine use. Univariate and multivariate logistic regression analyses were conducted to identify statistically significant associations. The primary outcomes were acceptance of telemedicine use during a hypothetical severe outbreak and after the COVID-19 pandemic. RESULTS: There were 109 survey respondents. Multivariate logistic regression analyses revealed that the expectation of government subsidies for telemedicine services was the strongest common driver and the only positive independent predictor of telemedicine use during a hypothetical severe outbreak (P=0.016) and after the COVID-19 pandemic (P=0.003). No negative independent predictors of telemedicine use during a hypothetical severe outbreak were identified. Negative independent predictors of telemedicine use after the COVID-19 pandemic included older age and residence in the New Territories (both P=0.001). CONCLUSION: Government support, such as telemedicine-specific subsidies, will be important for efforts to promote telemedicine use in Hong Kong during future severe outbreaks and after the COVID-19 pandemic. Robust dissemination of information regarding the advantages and disadvantages of telemedicine for the public, especially older adults, is needed.


Assuntos
COVID-19 , Telemedicina , Humanos , Idoso , COVID-19/epidemiologia , Hong Kong/epidemiologia , Pandemias , Estudos Transversais
2.
Ultrasound Obstet Gynecol ; 62(4): 512-521, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37616523

RESUMO

OBJECTIVE: To determine whether maternal serum glycosylated fibronectin (GlyFn) level in the first trimester increases the sensitivity of the Fetal Medicine Foundation (FMF) triple test, which incorporates mean arterial pressure, uterine artery pulsatility index and placental growth factor, when screening for pre-eclampsia (PE) in an Asian population. METHODS: This was a nested case-control study of Chinese women with a singleton pregnancy who were screened for PE at 11-13 weeks' gestation as part of a non-intervention study between December 2016 and June 2018. GlyFn levels were measured retrospectively in archived serum from 1685 pregnancies, including 101 with PE, using an enzyme-linked immunosorbent assay (ELISA), and from 448 pregnancies, including 101 with PE, using a point-of-care (POC) device. Concordance between ELISA and POC tests was assessed using Lin's correlation coefficient and Passing-Bablok and Bland-Altman analyses. GlyFn was transformed into multiples of the median (MoM) to adjust for maternal and pregnancy characteristics. GlyFn MoM was compared between PE and non-PE pregnancies, and the association between GlyFn MoM and gestational age at delivery with PE was assessed. Risk for developing PE was estimated using the FMF competing-risks model. Screening performance for preterm and any-onset PE using different biomarker combinations was quantified by area under the receiver-operating-characteristics curve (AUC) and detection rate (DR) at a 10% fixed false-positive rate (FPR). Differences in AUC between biomarker combinations were compared using the DeLong test. RESULTS: The concordance correlation coefficient between ELISA and POC measurements was 0.86 (95% CI, 0.83-0.88). Passing-Bablok analysis indicated proportional bias (slope, 1.08 (95% CI, 1.04-1.14)), with POC GlyFn being significantly higher compared with ELISA GlyFn. ELISA GlyFn in non-PE pregnancies was independent of gestational age at screening (P = 0.11), but significantly dependent on maternal age (P < 0.003), weight (P < 0.0002), height (P = 0.001), parity (P < 0.02) and smoking status (P = 0.002). Compared with non-PE pregnancies, median GlyFn MoM using ELISA and POC testing was elevated significantly in those with preterm PE (1.23 vs 1.00; P < 0.0001 and 1.18 vs 1.00; P < 0.0001, respectively) and those with term PE (1.26 vs 1.00; P < 0.0001 and 1.22 vs 1.00; P < 0.0001, respectively). GlyFn MoM was not correlated with gestational age at delivery with PE (P = 0.989). Adding GlyFn to the FMF triple test for preterm PE increased significantly the AUC from 0.859 to 0.896 (P = 0.012) and increased the DR at 10% FPR from 64.9% (95% CI, 48.7-81.1%) to 82.9% (95% CI, 66.4-93.4%). The corresponding DRs at 10% FPR for any-onset PE were 52.5% (95% CI, 42.3-62.5%) and 65.4% (95% CI, 55.2-74.5%), respectively. CONCLUSIONS: Adding GlyFn to the FMF triple test increased the screening sensitivity for both preterm and any-onset PE in an Asian population. Prospective non-intervention studies are needed to confirm these initial findings. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Fibronectinas , Proteínas Glicadas , Pré-Eclâmpsia , Primeiro Trimestre da Gravidez , Feminino , Humanos , Gravidez , Biomarcadores/sangue , Estudos de Casos e Controles , Idade Gestacional , Fator de Crescimento Placentário/sangue , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/diagnóstico , Primeiro Trimestre da Gravidez/sangue , Estudos Prospectivos , Fluxo Pulsátil , Estudos Retrospectivos , Artéria Uterina , Proteínas Glicadas/sangue , Fibronectinas/sangue , Adulto
3.
bioRxiv ; 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37162961

RESUMO

Natural products are ligands and potential inhibitors of Alzheimer's disease (AD) tau. Dihydromyricetin (DHM) is a CNS active natural product. Despite having signature polyphenolic character, DHM is ostensibly hydrophobic owing to intermolecular hydrogen bonds that shield hydrophilic phenols. Our research shows DHM becomes ionized at near-neutral pH allowing formulation of salts with transformed solubility. The MicroED co-crystal structure with trolamine reveals DHM salts as metastable solids with unlocked hydrogen bonding and a thermodynamic bent to solubilize in water. All salt formulations show better inhibitory activity against AD tau than the non-salt form, with efficacies correlating to enhanced solubilities. These results underscore the role of structural chemistry in guiding selection of solubilizing agents for chemical formulation. We propose DHM salts are appropriate formulations for research as dietary supplements to promote healthy aging by combating protein misfolding. Additionally, DHM is a suitable lead for medicinal chemistry and possible development of CNS pharmaceuticals.

5.
Ann Oncol ; 29(11): 2163-2174, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30295695

RESUMO

A European Society for Medical Oncology (ESMO)-sponsored expert meeting was held in Paris on 8 March 2018 which comprised 11 experts from academia, 11 experts from the pharmaceutical industry and 2 clinicians who were representatives of ESMO. The focus of the meeting was exclusively on the intratumoral injection/delivery of immunostimulatory agents with the aim of harmonizing the standard terms and methodologies used in the reporting of human intratumoral immunotherapy (HIT-IT) clinical trials to ensure quality assurance and avoid a blurring of the data reported from different studies. The goal was to provide a reference document, endorsed by the panel members that could provide guidance to clinical investigators, pharmaceutical companies, ethics committees, independent review boards, patient advocates and the regulatory authorities and promote an increase in the number and quality of HIT-IT clinical trials in the future. Particular emphasis was placed not only on the development of precise definitions to facilitate a better understanding between investigators but also on the importance of systematic serial biopsies as a driver for translational research and the need for the recording and reporting of data, to facilitate a better understanding of the key processes involved.


Assuntos
Ensaios Clínicos como Assunto/normas , Imunoterapia/normas , Neoplasias/terapia , Guias de Prática Clínica como Assunto/normas , Padrões de Prática Médica/normas , Projetos de Pesquisa , Pesquisa Biomédica , Europa (Continente) , Humanos , Neoplasias/imunologia , Seleção de Pacientes , Sociedades Médicas , Microambiente Tumoral
6.
Nat Mater ; 17(10): 887-893, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30202110

RESUMO

Intergranular stress-corrosion cracking (IGSCC) is a form of environmentally induced crack propagation causing premature failure of elemental metals and alloys. It is believed to require the simultaneous presence of tensile stress and corrosion; however, the exact nature of this synergy has eluded experimental identification. For noble metal alloys such as Ag-Au, IGSCC is a consequence of dealloying corrosion, forming a nanoporous gold layer that is believed to have the ability to transmit cracks into grain boundaries in un-dealloyed parent phase via a pure mechanical process. Here using atomic-scale techniques and statistical characterizations for this alloy system, we show that the separate roles of stress and anodic dissolution can be decoupled and that the apparent synergy exists owing to rapid time-dependent morphology changes at the dealloyed layer/parent phase interface. We discuss the applicability of our findings to the IGSCC of important engineering Fe- and Ni-based alloys in critical applications.

7.
Ultrasound Obstet Gynecol ; 52(5): 639-647, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28976627

RESUMO

OBJECTIVES: To define a protocol for the first-trimester assessment of uterine artery pulsatility index (UtA-PI) using the new transverse technique, to evaluate UtA-PI measured using the transverse approach vs that obtained using the conventional sagittal approach and to determine if accelerated onsite training (in both methods) of inexperienced sonographers can achieve reproducible UtA-PI measurements comparable with those obtained by an experienced sonographer. METHODS: This was a prospective observational study of women with a singleton pregnancy attending for routine combined first-trimester screening at 11 to 13 + 6 weeks' gestation. The study consisted of two parts, each conducted at a different center (Part 1 in Calgary, Canada and Part 2 in Hong Kong). In Part 1, UtA-PI measurements were performed using the transverse and sagittal techniques by four sonographers trained in both methods, in 10 cases each, and measurement indices (PI), time required and subjective difficulty in obtaining satisfactory measurements were compared. The one sample t-test and Wilcoxon signed rank test were used when appropriate. Bland-Altman plots were used to assess measurement agreement, and intraclass correlation coefficient (ICC) was used to evaluate measurement reliability. A target plot was used to assess measures of central tendency and dispersion. In Part 2, one experienced and three inexperienced sonographers prospectively measured UtA-PI using both approaches in 42 and 35 women, respectively. Inexperienced sonographers underwent accelerated onsite training by the experienced sonographer. Measurement approach and sonographer order were on a random basis. ICC, Bland-Altman and Passing-Bablok analyses were performed to assess measurement agreement and reliability and effect of accelerated training. RESULTS: In Part 1, no difference was observed between the two techniques in mean time to acquire the measurements (118 s for sagittal vs 106 s for transverse; P = 0.38). The four sonographers reported that the transverse technique was subjectively easier to perform (P = 0.04). Bias and ICC for mean UtA-PI between sagittal and transverse measurements were -0.05 (95% limits of agreement, -0.48 to 0.37) and 0.94, respectively. Measurements obtained using the transverse technique after correcting for gestational age were significantly closer to the expected distribution than those obtained using the sagittal technique. In Part 2, there were no significant differences in median UtA-PI measured using the different approaches for both experienced and inexperienced sonographers (P > 0.05 for all sonographers). Mean UtA-PI measurement reliability between approaches was high for the experienced (ICC = 0.92) and inexperienced (ICC > 0.80) sonographers. UtA-PI measurement approaches did not deviate from linearity, while bias ranged from -0.10 to 0.07. The median time required was similar between the techniques (56.1 s for sagittal vs 49.3 s for transverse; P = 0.054). CONCLUSIONS: This novel transverse approach for the measurement of UtA-PI in the first trimester appears to be comparable with the sagittal approach in terms of reliability, reproducibility and time required, and may be easier to perform. Providing accelerated onsite training can be helpful for improving the reliability of UtA-PI measurements and could potentially facilitate the broad implementation of first-trimester pre-eclampsia screening. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Pré-Eclâmpsia/diagnóstico por imagem , Ultrassonografia Pré-Natal , Artéria Uterina/diagnóstico por imagem , Adulto , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Pré-Eclâmpsia/fisiopatologia , Valor Preditivo dos Testes , Gravidez , Primeiro Trimestre da Gravidez , Estudos Prospectivos , Fluxo Pulsátil , Artéria Uterina/fisiologia
8.
Eye (Lond) ; 30(8): 1118-22, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27256302

RESUMO

PurposeTo estimate patient adherence with glaucoma therapy and identify factors associated with adherence using computerised patient prescribing records.MethodsIdentification of patients diagnosed with glaucoma, ocular hypertension or suspect glaucoma and/or prescribed topical glaucoma medications registered at a United Kingdom general practice with 13 422 patients. Adherence was defined as the average difference in the actual number of prescriptions collected annually compared to twelve prescriptions required annually (one bottle per month) over the duration of treatment.ResultsOverall, 278 patients were identified of which 139 (50%) were male. The average age was 72 years (range: 22-100). A total of 206 patients (74%) were prescribed glaucoma treatment. Adherence varied significantly between age groups with younger patients demonstrating poorest adherence (P=0.0347). There was no statistical difference when comparing medication class, diagnosis, co-morbidities, or the number of drops being taken.ConclusionsGlaucoma treatment adherence improves with increasing age. Older patients require more prescriptions and may be experiencing drop wastage. Younger patients should be targeted with educational interventions to improve their understanding of glaucoma, and older patients for drop technique review. General practices are well placed to provide such interventions.


Assuntos
Anti-Hipertensivos/uso terapêutico , Prescrições de Medicamentos/estatística & dados numéricos , Glaucoma de Ângulo Aberto/tratamento farmacológico , Adesão à Medicação/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Feminino , Medicina Geral , Humanos , Masculino , Pessoa de Meia-Idade , Hipertensão Ocular/tratamento farmacológico , Fatores de Risco , Reino Unido/epidemiologia , Adulto Jovem
9.
Mol Biosyst ; 11(7): 2082-95, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25996455

RESUMO

The human protein kinases play a fundamental regulatory role in orchestrating functional processes in complex cellular networks. Understanding how conformational equilibrium between functional kinase states can be modulated by ligand binding or mutations is critical for quantifying molecular basis of allosteric regulation and drug resistance. In this work, molecular dynamics simulations of the Abl kinase complexes with cancer drugs (Imatinib and Dasatinib) were combined with structure-based network modeling to characterize dynamics of the residue interaction networks in these systems. The results have demonstrated that structural architecture of kinase complexes can produce a small-world topology of the interaction networks. Our data have indicated that specific Imatinib binding to a small number of highly connected residues could lead to network-bridging effects and allow for efficient allosteric communication, which is mediated by a dominant pathway sensitive to the unphosphorylated Abl state. In contrast, Dasatinib binding to the active kinase form may activate a broader ensemble of allosteric pathways that are less dependent on the phosphorylation status of Abl and provide a better balance between the efficiency and resilience of signaling routes. Our results have unveiled how differences in the residue interaction networks and allosteric communications of the Abl kinase complexes can be directly related to drug resistance effects. This study offers a plausible perspective on how efficiency and robustness of the residue interaction networks and allosteric pathways in kinase structures may be associated with protein responses to drug binding.


Assuntos
Antineoplásicos/química , Resistencia a Medicamentos Antineoplásicos , Mesilato de Imatinib/química , Proteínas Proto-Oncogênicas c-abl/química , Regulação Alostérica , Domínio Catalítico , Dasatinibe/química , Humanos , Ligação de Hidrogênio , Simulação de Dinâmica Molecular , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-abl/antagonistas & inibidores
10.
J Neuroimmunol ; 262(1-2): 100-5, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23838529

RESUMO

Classical multiple sclerosis (CMS) and neuromyelitis optica spectrum disorders (NMOSD) are distinct central nervous system inflammatory demyelinating disorders (CNS IDD). Early diagnosis of CNS IDD is important as appropriate immunotherapies to optimize prognosis. We studied the diagnoses of CNS IDD among Hong Kong Chinese in a hospital-based setting. Consecutive Chinese patients who presented to our hospital with clinically isolated syndrome and subsequently diagnosed to have CNS IDD from 1980 to 2010 were reviewed. Patients with known diagnosis of CNS IDD referred for further care were excluded. Serial sera were assayed for aquaporin-4 autoantibodies (AQP4 Ab), at least 3 assays within 2-5years. A total of 210 patients diagnosed to have CNS IDD with disease duration of at least 2years were studied. Among 198 patients with serial sera available, 40 (20.2%, 20 had NMO and 20 other NMOSD) were AQP4 Ab-positive. Four patients who were AQP4 Ab-negative on the initial assay converted to AQP4 Ab-positive on repeated assays. The diagnoses of 210 patients were CMS in 88 (41.9%), NMOSD 47 (22.4%, 27 NMO, 20 other NMOSD), single attack of myelitis 23 (11.0%), single attack of optic neuritis 21 (10.0%), relapsing myelitis 10 (4.8%), acute disseminated encephalomyelitis (ADEM) 9 (4.3%), relapsing optic neuritis in 6 (2.9%), opticospinal multiple sclerosis 3 (1.4%) and single attack of brainstem encephalitis 3 (1.4%). Compared to CMS, NMOSD patients had older onset age, lower frequencies of brain MRI abnormalities and CSF OCB, higher frequency of LETM, higher CNS inflammation attack frequency in the first 2years, worse clinical outcome with higher EDSS score and mortality rate. This hospital-based study suggests that CMS (41.9%) and NMOSD (22.4%) are the most common CNS IDD among Hong Kong Chinese. NMOSD has worse clinical outcome than CMS. Detection of AQP4 Ab facilitates early diagnosis and prompts immunotherapies of NMOSD.


Assuntos
Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/patologia , Esclerose Múltipla/patologia , Neuromielite Óptica/patologia , Adolescente , Adulto , Idade de Início , Idoso , Criança , Estudos de Coortes , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/epidemiologia , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/imunologia , Feminino , Hong Kong/epidemiologia , Humanos , Inflamação/epidemiologia , Inflamação/imunologia , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/epidemiologia , Esclerose Múltipla/imunologia , Neuromielite Óptica/epidemiologia , Neuromielite Óptica/imunologia , Adulto Jovem
11.
Oncogene ; 30(19): 2207-18, 2011 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-21242980

RESUMO

The transcriptional activity of the androgen receptor (AR) is regulated by both ligand binding and post-translational modifications, including acetylation and small ubiquitin-like modifier (SUMO)ylation. Histone deacetylases (HDACs) are known to catalyze the removal of acetyl groups from both histones and non-histone proteins. In this study, we report that HDAC4 binds to and inhibits the activity of the AR. This inhibition was found to depend on the SUMOylation, instead of deacetylation, of the AR. Consistently, HDAC4 increases the level of AR SUMOylation in both whole-cell and cell-free assay systems, raising the possibility that the deacetylase may act as an E3 ligase for AR SUMOylation. Knock down of HDAC4 increases the activity of endogenous AR and androgen induction of prostate-specific antigen expression and prostate cancer cell growth, which is associated with decreased SUMOylation of the receptor. Overall, the studies identify HDAC4 as a positive regulator for AR SUMOylation, revealing a deacetylase-independent mechanism of HDAC action in prostate cancer cells.


Assuntos
Antagonistas de Androgênios/farmacologia , Histona Desacetilases/metabolismo , Receptores Androgênicos/efeitos dos fármacos , Proteínas Repressoras/metabolismo , Sumoilação , Sequência de Bases , Biocatálise , Linhagem Celular Tumoral , Primers do DNA , Ensaio de Imunoadsorção Enzimática , Humanos , Receptores Androgênicos/metabolismo , Transdução de Sinais
12.
Phytomedicine ; 17(8-9): 702-5, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20089387

RESUMO

We studied the effects of schisandrol A (SCH) and gomisin A (GOM), two of the main bioactive components of Fructus Schisandrae chinensis, on cytochrome P450-3A4 (CYP3A4) activity and cellular glutathione (GSH) level. In a cell-free system both SCH and GOM inhibited CYP3A4 activity with IC(50) values of 32.02 microM and 1.39 microM, respectively. SCH or GOM at concentrations up to 100 microM did not alter cellular GSH level in regular HepG2 cells and P-glycoprotein overexpressing HepG2-DR cells. Since SCH and GOM may reverse multidrug resistance (MDR) by impeding the activity of P-glycoprotein, a membrane xenobiotic exporter, SCH or GOM could affect cellular drug metabolism in addition to drug uptake.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Ciclo-Octanos/farmacologia , Inibidores do Citocromo P-450 CYP3A , Dioxóis/farmacologia , Glutationa/metabolismo , Lignanas/farmacologia , Extratos Vegetais/farmacologia , Schisandra/química , Ciclo-Octanos/isolamento & purificação , Citocromo P-450 CYP3A , Dioxóis/isolamento & purificação , Resistência a Múltiplos Medicamentos , Frutas , Células Hep G2 , Interações Ervas-Drogas , Humanos , Concentração Inibidora 50 , Lignanas/isolamento & purificação , Extratos Vegetais/química
13.
Appl Radiat Isot ; 68(4-5): 718-21, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19857974

RESUMO

In this work, the influence of Magnolol on the bystander effect in alpha-particle irradiated Chinese hamster ovary (CHO) cells was examined. The bystander effect was studied through medium transfer experiments. Cytokinesis-block micronucleus (CBMN) assay was performed to quantify the chromosome damage induced by alpha-particle irradiation. Our results showed that the alpha-particle induced micronuclei (MN) frequencies were suppressed with the presence of Magnolol.


Assuntos
Compostos de Bifenilo/administração & dosagem , Efeito Espectador/efeitos dos fármacos , Aberrações Cromossômicas/efeitos dos fármacos , Aberrações Cromossômicas/efeitos da radiação , Lignanas/administração & dosagem , Tolerância a Radiação/efeitos dos fármacos , Partículas alfa , Animais , Efeito Espectador/efeitos da radiação , Células CHO , Cricetinae , Cricetulus , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Protetores contra Radiação/administração & dosagem
14.
Ann Oncol ; 20(9): 1589-1595, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19491285

RESUMO

BACKGROUND: This study reports the results of hepatic arterial infusion (HAI) with floxuridine (FUDR) and dexamethasone (dex) in patients with unresectable intrahepatic cholangiocarcinoma (ICC) or hepatocellular carcinoma (HCC) and investigates dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) assessment of tumor vascularity as a biomarker of outcome. PATIENTS AND METHODS: Thirty-four unresectable patients (26 ICC and eight HCC) were treated with HAI FUDR/dex. Radiologic dynamic and pharmacokinetic parameters related to tumor perfusion were analyzed and correlated with response and survival. RESULTS: Partial responses were seen in 16 patients (47.1%); time to progression and response duration were 7.4 and 11.9 months, respectively. Median follow-up and median survival were 35 and 29.5 months, respectively; 2-year survival was 67%. DCE-MRI data showed that patients with pretreatment integrated area under the concentration curve of gadolinium contrast over 180 s (AUC 180) >34.2 mM.s had a longer median survival than those with AUC 180 <34 mM.s (35.1 versus 19.1 months, P = 0.002). Decreased volume transfer exchange between the vascular space and extracellular extravascular space (-DeltaK(trans)) and the corresponding rate constant (-Deltak(ep)) on the first post-treatment scan both predicted survival. CONCLUSIONS: In patients with unresectable primary liver cancer, HAI therapy can be effective and safe. Pretreatment and early post-treatment changes in tumor perfusion characteristics may predict treatment outcome.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia do Câncer por Perfusão Regional , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/mortalidade , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Neoplasias dos Ductos Biliares/tratamento farmacológico , Ductos Biliares Intra-Hepáticos/patologia , Carcinoma Hepatocelular/tratamento farmacológico , Colangiocarcinoma/tratamento farmacológico , Dexametasona/administração & dosagem , Intervalo Livre de Doença , Feminino , Floxuridina/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Resultado do Tratamento
15.
Clin Cancer Res ; 13(19): 5841-6, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17908977

RESUMO

PURPOSE: Flavopiridol is a cyclin-dependent kinase inhibitor that enhances docetaxel-induced apoptosis in a sequence-specific manner. In vivo, docetaxel must precede flavopiridol by at least 4 h to induce this effect. We conducted a phase I trial of weekly, sequential docetaxel followed 4 h later by flavopiridol in patients with advanced solid tumors. EXPERIMENTAL DESIGN: Docetaxel at a fixed dose of 35 mg/m2 was administered over 30 min, followed 4 h later by escalating doses of flavopiridol, ranging from 20 to 80 mg/m2 in successive cohorts, administered weekly over 1 h. This schedule was repeated for 3 weeks of each 4-week cycle. RESULTS: Twenty-seven evaluable patients were enrolled. The combination was well tolerated, with one dose-limiting toxicity occurring at flavopiridol 70 mg/m2 (grade 3 mucositis) and one dose-limiting toxicity at 80 mg/m2 (grade 4 neutropenia). We observed 1 complete response in a patient with pancreatic carcinoma and 4 partial responses in pancreatic (1), breast (2), and ovarian (1) cancer patients. Stable disease was seen in 10 patients. Pharmacokinetic studies showed Cmax ranging from 1.49 +/- 0.69 micromol/L (flavopiridol 20 mg/m2) to 4.54 +/- 0.08 micromol/L (flavopiridol 60 mg/m2) in cycle 1. CONCLUSIONS: Treatment with weekly, sequential docetaxel followed by flavopiridol is an effective and safe regimen at all flavopiridol dose levels. The pharmacokinetic data indicate that concentrations of flavopiridol that enhance the effects of docetaxel both in vitro and in vivo can be achieved. Clinical activity is encouraging, even in patients who have received a prior taxane and in patients with gemcitabine-refractory metastatic pancreatic cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Flavonoides/administração & dosagem , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Piperidinas/administração & dosagem , Taxoides/administração & dosagem , Adulto , Idoso , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Docetaxel , Esquema de Medicação , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Gencitabina
16.
Radiat Prot Dosimetry ; 122(1-4): 160-2, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17132662

RESUMO

The present paper studied the feasibility of applying comet assay to evaluate the DNA damage in individual HeLa cervix cancer cells after alpha-particle irradiation. We prepared thin CR-39 detectors (<20 microm) as cell-culture substrates, with UV irradiation to shorten the track formation time. After irradiation of the HeLa cells by alpha particles, the tracks on the underside of the CR-39 detector were developed by chemical etching in (while floating on) a 14 N KOH solution at 37 degrees C. Comet assay was then applied. Diffusion of DNA out of the cells could be generally observed from the images of stained DNA. The alpha-particle tracks corresponding to the comets developed on the underside of the CR-39 detectors could also be observed by just changing the focal plane of the confocal microscope.


Assuntos
Ensaio Cometa/instrumentação , Dano ao DNA , DNA/genética , DNA/efeitos da radiação , Radiometria/instrumentação , Transdutores , Partículas alfa , Células Cultivadas , Ensaio Cometa/métodos , DNA/química , DNA/ultraestrutura , Desenho de Equipamento , Análise de Falha de Equipamento , Células HeLa , Humanos , Radiobiologia/instrumentação , Radiobiologia/métodos , Radiometria/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Aliment Pharmacol Ther ; 23(12): 1703-11, 2006 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-16817913

RESUMO

BACKGROUND: Interleukin-1beta is a pro-inflammatory cytokine that may influence host defence against viral infection. AIM: To investigate the impact of interleukin-1beta gene polymorphism on the response to anti-viral treatment. METHOD: Hepatitis B e antigen-positive chronic hepatitis B patients who have completed a randomized study of peginterferon alpha-2b and lamivudine combination vs. lamivudine monotherapy were included. Sustained responders were patients who had persistent hepatitis B e antigen loss and less than two occasions with hepatitis B virus DNA >100 000 copies/mL at any time up to week 76 post-treatment. Polymorphisms at interleukin-1beta-511, -31 and -3954 and interleukin-1 receptor antagonist (RN) were studied. RESULTS: Eighty-eight patients were studied and 18 (20%) patients developed sustained response. Near complete linkage disequilibrium was observed between interleukin-1beta-511 and -31 loci. After adjustment for the potential confounding effects of treatment allocation, hepatitis B virus genotype, pre-treatment alanine aminotransferase and hepatitis B virus DNA levels, genotype C/T at interleukin-1beta-511 was found to be associated with higher sustained response than genotype C/C (adjusted odds ratio 10.4, 95% CI 1.1, 96.9, P = 0.040). The proportion of sustained responders tend to be higher among patients with allele T at interleukin-1beta-511 (83%) than those without (70%) (P = 0.058). CONCLUSION: High interleukin-1beta production genotype at position -511 has a favourable response to anti-viral treatments.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/genética , Interferon-alfa/uso terapêutico , Interleucina-1/genética , Lamivudina/uso terapêutico , Polietilenoglicóis/uso terapêutico , Polimorfismo Genético/genética , Adulto , Povo Asiático/etnologia , Povo Asiático/genética , Feminino , Hepatite B Crônica/tratamento farmacológico , Humanos , Interferon alfa-2 , Masculino , Proteínas Recombinantes , Resultado do Tratamento
18.
Gut ; 53(10): 1494-8, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15361502

RESUMO

BACKGROUND: Identification of risk factors for the development of hepatocellular carcinoma (HCC) is important for HCC surveillance in chronic hepatitis B virus (HBV) infection. Our aim was to study the independent risk factors and effect of HBV genotypes on HCC development in a prospective longitudinal cohort of chronic hepatitis B patients. PATIENTS AND METHODS: Chronic hepatitis B patients recruited since 1997 were prospectively followed up for the development of HCC. HCC was diagnosed by a combination of alpha fetoprotein, imaging, and histology. Liver cirrhosis was defined as ultrasonic features of cirrhosis together with hypersplenism, ascites, varices, and/or encephalopathy. RESULTS: In total, 426 patients were followed up for 1664 person years; median 225 (range 12-295) weeks. Forty nine (11%) patients had underlying clinical liver cirrhosis. A total of 242 (57%) and 179 (42%) patients had HBV genotypes C and B, respectively. Twenty five patients developed HCC in a median follow up of 121 (range 14-236) weeks. The overall incidence of HCC was 1502 cases per 100 000 person years. On multivariate analysis, clinical liver cirrhosis and HBV genotype C infection were independently associated with HCC development, with an adjusted relative risk of 10.24 (95% confidence interval (CI) 4.39-23.89; p<0.001) and 2.84 (95% CI 1.05-7.72; p = 0.040), respectively. Patient age, sex, hepatitis B e antigen (HBeAg) status, alanine aminotransferase (ALT) levels, and basal core promoter mutations did not predict HCC development. Patients infected with HBV genotype C tended to have persistently positive HBeAg or fluctuating HBeAg status and higher ALT levels during the follow up period. CONCLUSION: Genotype C HBV infection is an independent risk factor for HCC development in addition to liver cirrhosis.


Assuntos
Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Neoplasias Hepáticas/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Seguimentos , Genótipo , Vírus da Hepatite B/classificação , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/complicações , Humanos , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
19.
Aust Dent J ; 47(4): 327-30, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12587769

RESUMO

BACKGROUND: The aim of this study was to evaluate the comparative efficacy of three commonly used analgesics (Panadeine, Diflunisal and Etodolac) in the control of pain after third molar surgery under local anaesthesia. METHODS: A randomized control study. Outcome of primary efficacy was judged by overall assessment of the area under the curve of graphs for pain intensity, measured from serial visual analogue scales over a 24-hour period. Other measures of efficacy included the number (per cent) of patients who took 'additional' analgesics and the incidence of adverse effects occurring in each treatment group over the study period. RESULTS: The three drugs were effective in the control of post-operative pain (p<0.01). Variations in pain intensity and the use of additional medication between the treatment groups were observed over the study period. The Diflunisal group experienced less pain than the Panadeine or Etodolac group (p<0.01). Furthermore, a lesser number of those in the Diflunisal group used additional medication compared to the other two groups (p<0.01). The incidence of side effects from all three drugs was low. CONCLUSION: Diflunisal is superior in the control of pain following third molar surgery under local anaesthesia than either Panadeine or Etodolac, and has few side effects.


Assuntos
Analgésicos/uso terapêutico , Anestesia Local , Dente Serotino/cirurgia , Dor Pós-Operatória/prevenção & controle , Extração Dentária , Acetaminofen/efeitos adversos , Acetaminofen/uso terapêutico , Analgésicos/efeitos adversos , Analgésicos não Narcóticos/efeitos adversos , Analgésicos não Narcóticos/uso terapêutico , Analgésicos Opioides/efeitos adversos , Analgésicos Opioides/uso terapêutico , Anestesia Dentária , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/uso terapêutico , Área Sob a Curva , Distribuição de Qui-Quadrado , Codeína/efeitos adversos , Codeína/uso terapêutico , Inibidores de Ciclo-Oxigenase/efeitos adversos , Inibidores de Ciclo-Oxigenase/uso terapêutico , Diflunisal/efeitos adversos , Diflunisal/uso terapêutico , Combinação de Medicamentos , Etodolac/efeitos adversos , Etodolac/uso terapêutico , Seguimentos , Humanos , Medição da Dor , Estatísticas não Paramétricas , Dente Impactado/cirurgia , Resultado do Tratamento
20.
J Physiol ; 533(Pt 2): 389-405, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11389200

RESUMO

1. We used the patch-clamp technique, in conjunction with membrane capacitance measurement, fluorescence measurement of intracellular calcium concentration ([Ca(2+)](i)), and flash photolysis of caged Ca(2+) to study exo- and endocytosis in identified rat corticotrophs. 2. Exocytosis stimulated by depolarization pulses was typically followed by a 'slow' endocytosis that retrieved the membrane with a time constant of approximately 6 s. The efficiency (the endocytosis/exocytosis amplitude ratio) of 'slow' endocytosis was approximately 1.2 at [Ca(2+)](i) < 3 microM and increased to approximately 1.6 at [Ca(2+)](i) > 3 microM. 3. Whole-cell dialysis through a patch pipette did not affect the kinetics and the efficiency of 'slow' endocytosis, but the amplitude of exocytosis was reduced. 4. 'Slow' endocytosis did not require sustained [Ca(2+)](i) elevation and its kinetics was only weakly [Ca(2+)](i) dependent. Our results suggest that 'slow' endocytosis involves a Ca(2+) sensor with a high Ca(2+) affinity (approximately 500 nM). 5. At high [Ca(2+)](i) (> 10 microM), the 'slow' endocytosis was frequently preceded by a 'fast' endocytosis that comprised multiple steps of rapid decrease in membrane capacitance. 6. Neither calmodulin nor calcineurin appeared to be the Ca(2+) sensor for endocytosis because the two forms of endocytosis were not affected by the calmodulin inhibitor calmidazolium (500 microM) or the calcineurin inhibitors cyclosporin A (1 microM) and calcineurin autoinhibitory peptide (1 mg ml(-1)). Ba(2+), a poor activator of calmodulin, could support both forms of endocytosis but slowed the kinetics of 'slow' endocytosis approximately 2-fold. 7. Non-hydrolysable analogues of GTP (GDP-beta-S) and ATP (ATP-gamma-S) also failed to inhibit either form of endocytosis, indicating that neither GTP nor ATP was essential for endocytosis. 8. We suggest that the high Ca(2+) affinity of 'slow' endocytosis may be important for maintaining continuous cycles of exocytosis-endocytosis during sustained adrenocorticotropin secretion in corticotrophs.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Cálcio/metabolismo , Endocitose/fisiologia , Hipófise/citologia , Hipófise/metabolismo , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/farmacologia , Animais , AMP Cíclico/farmacologia , Eletrofisiologia , Endocitose/efeitos dos fármacos , Exocitose/efeitos dos fármacos , Exocitose/fisiologia , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Cinética , Masculino , Potenciais da Membrana/fisiologia , Modelos Biológicos , Técnicas de Patch-Clamp , Ratos , Ratos Sprague-Dawley
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