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1.
Med J Malaysia ; 79(1): 15-20, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38287752

RESUMO

INTRODUCTION: The use of dexamethasone (DXM) has been associated with decreased mortality in the patients with hypoxemia during the coronavirus disease-2019 (COVID-19) pandemic, while the outcomes with methylprednisolone (MTP) have been mixed. This real-life study aimed to evaluate the outcomes of patients with severe respiratory failure due to COVID-19 who were treated with high doses of MTP. MATERIALS AND METHODS: This retrospective cohort study enrolled hospitalised patients between May 2021 and August 2021, aged 18 years and above, with severe respiratory failure defined by a ratio of oxygen saturation to fraction of inspired oxygen (SF ratio) of less than 235. The treatment protocol involved administering high-dose MTP for 3 days, followed by DXM, and the outcomes were compared with those of patients who received DXM alone (total treatment duration of 10 days for both groups). RESULTS: A total of 99 patients were enrolled, with 79 (79.8%) receiving pulse MTP therapy and 20 (20.2%) being treated with DXM only. The SF ratio significantly improved from a mean of 144.49 (±45.16) at baseline to 208 (±85.19) at 72 hours (p < 0.05), with a mean difference of 63.51 (p < 0.001) in patients who received ≤750 mg of MTP. Additionally, in patients who received >750 mg of MTP, the SF ratio improved from a baseline mean of 130.39 (±34.53) to 208.44 (±86.61) at 72 hours (p < 0.05), with a mean difference of 78.05 (p = 0.001). In contrast, patients who received DXM only demonstrated an SF ratio of 132.85 (±44.1) at baseline, which changed minimally to 133.35 (±44.4) at 72 hours (p = 0.33), with a mean difference of 0.50 (p = 0.972). The incidence of nosocomial infection was higher in the MTP group compared with the DXM group (40.5% vs. 35%, p = 0.653), with a relative risk of 1.16 (95% CI: 0.60-2.23). CONCLUSION: MTP did not demonstrate a significant reduction in intubation or intensive care unit admissions. Although a high dose of MTP improved gas exchange in patients with severe and critical COVID-19, it did not provide an overall mortality benefit compared to standard treatment.


Assuntos
COVID-19 , Pneumonia , Insuficiência Respiratória , Humanos , Metilprednisolona , Estudos Retrospectivos , SARS-CoV-2 , Malásia , Tratamento Farmacológico da COVID-19 , Pneumonia/induzido quimicamente , Dexametasona/uso terapêutico
2.
Br J Surg ; 108(5): 554-565, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34043776

RESUMO

BACKGROUND: Bariatric surgery can be effective in weight reduction and diabetes remission in some patients, but is expensive. The costs of bariatric surgery in patients with obesity and type 2 diabetes mellitus (T2DM) were explored here. METHODS: Population-based retrospectively gathered data on patients with obesity and T2DM from the Hong Kong Hospital Authority (2006-2017) were evaluated. Direct medical costs from baseline up to 60 months were calculated based on the frequency of healthcare service utilization and dispensing of diabetes medication. Charlson Co-morbidity Index (CCI) scores and co-morbidity rates were measured to compare changes in co-morbidities between surgically treated and control groups over 5 years. One-to-five propensity score matching was applied. RESULTS: Overall, 401 eligible surgical patients were matched with 1894 non-surgical patients. Direct medical costs were much higher for surgical than non-surgical patients in the index year (€36 752 and €5788 respectively; P < 0·001) mainly owing to the bariatric procedure. The 5-year cumulative costs incurred by surgical patients were also higher (€54 135 versus €28 603; P < 0·001). Although patients who had bariatric surgery had more visits to outpatient and allied health professionals than those who did not across the 5-year period, surgical patients had shorter length of stay in hospitals than non-surgical patients in year 2-5. Surgical patients had significantly better CCI scores than controls after the baseline measurement (mean 3·82 versus 4·38 at 5 years; P = 0·016). Costs of glucose-lowering medications were similar between two groups, except that surgical patients had significantly lower costs of glucose-lowering medications in year 2 (€973 versus €1395; P = 0.012). CONCLUSION: Bariatric surgery in obese patients with T2DM is expensive, but leads to an improved co-morbidity profile, and reduced length of hospitalization.


Assuntos
Cirurgia Bariátrica/economia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Obesidade/economia , Assistência Ambulatorial/economia , Assistência Ambulatorial/estatística & dados numéricos , Estudos de Casos e Controles , Comorbidade , Diabetes Mellitus Tipo 2/economia , Serviço Hospitalar de Emergência/economia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Hong Kong/epidemiologia , Humanos , Hipoglicemiantes/economia , Hipoglicemiantes/uso terapêutico , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Obesidade/cirurgia , Visita a Consultório Médico/economia , Visita a Consultório Médico/estatística & dados numéricos , Estudos Retrospectivos
4.
J Endocrinol Invest ; 43(11): 1645-1654, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32307641

RESUMO

OBJECTIVES: A trial-based comparison of the use of resources, costs and health utility outcomes of fine-needle aspiration cytology (FNAC), and watchful observation for incidental small (< 2 cm) thyroid nodules was performed using data from the randomized controlled trial (RCT). METHODS: Using data from 314 patients, healthcare-related use of resources, costs, health utility, and quality-adjusted life years (QALYs) were estimated at 12 months after first presentation of incidental thyroid nodule(s) on an intention-to-treat basis with adjustment for covariates. Uncertainty about the incremental cost-effectiveness ratio for FNAC versus watchful management at 12 months of follow-up was incorporated using bootstrapping. Multiple imputation methods were used to deal with missing data. RESULTS: FNAC management was associated with greater use of healthcare resources and mean direct healthcare costs per patient (US$542.47 vs US$411.55). Lower mean 12-month QALYs per patient in FNAC was observed in comparison to watchful observation (0.752 versus 0.758). The probability that FNAC management was cost-effective compared with watchful management at a willingness-to-pay threshold of US50,000 per QALY gained was 26.5%. CONCLUSION: Based on 12-month data from RCT, watchful observation appeared cost-saving compared to FNAC in patients with incidental thyroid nodules that have a low-suspicion sonographic pattern and measure between 1.0 and 2.0 cm from healthcare provider perspective. CLINICALTRIALS. GOV IDENTIFIER: NCT02398721.


Assuntos
Citodiagnóstico/economia , Nódulo da Glândula Tireoide/terapia , Conduta Expectante/economia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina/economia , Biópsia por Agulha Fina/estatística & dados numéricos , China/epidemiologia , Análise Custo-Benefício , Citodiagnóstico/métodos , Citodiagnóstico/estatística & dados numéricos , Feminino , Custos de Cuidados de Saúde/estatística & dados numéricos , Recursos em Saúde/economia , Recursos em Saúde/estatística & dados numéricos , Humanos , Achados Incidentais , Masculino , Pessoa de Meia-Idade , Nódulo da Glândula Tireoide/economia , Nódulo da Glândula Tireoide/epidemiologia , Nódulo da Glândula Tireoide/patologia , Conduta Expectante/estatística & dados numéricos
5.
Clin Microbiol Infect ; 25(3): 372-378, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29906597

RESUMO

OBJECTIVES: Automated point-of-care molecular assays have greatly shortened the turnaround time of respiratory virus testing. One of the major bottlenecks now lies at the specimen collection step, especially in a busy clinical setting. Saliva is a convenient specimen type that can be provided easily by adult patients. This study assessed the diagnostic validity, specimen collection time and cost associated with the use of saliva. METHODS: This was a prospective diagnostic validity study comparing the detection rate of respiratory viruses between saliva and nasopharyngeal aspirate (NPA) among adult hospitalized patients using Xpert® Xpress Flu/RSV. The cost and time associated with the collection of saliva and nasopharyngeal specimens were also estimated. RESULTS: Between July and October 2017, 214 patients were recruited. The overall agreement between saliva and NPA was 93.3% (196/210, κ 0.851, 95% CI 0.776-0.926). There was no significant difference in the detection rate of respiratory viruses between saliva and NPA (32.9% (69/210) versus 35.7% (75/210); p 0.146). The overall sensitivity and specificity were 90.8% (81.9%-96.2%) and 100% (97.3%-100%), respectively, for saliva, and were 96.1% (88.9%-99.2%) and 98.5% (94.7%-99.8%), respectively, for NPA. The time and cost associated with the collection of saliva were 2.26-fold and 2.59-fold lower, respectively, than those of NPA. CONCLUSIONS: Saliva specimens have high sensitivity and specificity in the detection of respiratory viruses by an automated multiplex Clinical Laboratory Improvement Amendments-waived point-of-care molecular assay when compared with those of NPA. The use of saliva also reduces the time and cost associated with specimen collection.


Assuntos
Técnicas de Diagnóstico Molecular/métodos , Testes Imediatos , Infecções Respiratórias/diagnóstico , Manejo de Espécimes/métodos , Idoso , Idoso de 80 Anos ou mais , Custos e Análise de Custo , Feminino , Humanos , Vírus da Influenza A/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular/normas , Nasofaringe/virologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções Respiratórias/virologia , Saliva/virologia , Sensibilidade e Especificidade , Manejo de Espécimes/economia , Fatores de Tempo
6.
Diabet Med ; 34(9): 1276-1283, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28636749

RESUMO

AIM: To develop models to estimate the direct medical costs associated with diabetes-related complications in the event year and in subsequent years. METHODS: The public direct medical costs associated with 13 diabetes-related complications were estimated among a cohort of 128 353 people with diabetes over 5 years. Private direct medical costs were estimated from a cross-sectional survey among 1825 people with diabetes. We used panel data regression with fixed effects to investigate the impact of each complication on direct medical costs in the event year and subsequent years, adjusting for age and co-existing complications. RESULTS: The expected annual public direct medical cost for the baseline case was US$1,521 (95% CI 1,518 to 1,525) or a 65-year-old person with diabetes without complications. A new lower limb ulcer was associated with the biggest increase, with a multiplier of 9.38 (95% CI 8.49 to 10.37). New end-stage renal disease and stroke increased the annual medical cost by 5.23 (95% CI 4.70 to 5.82) and 5.94 (95% CI 5.79 to 6.10) times, respectively. History of acute myocardial infarction, congestive heart failure, stroke, end-stage renal disease and lower limb ulcer increased the cost by 2-3 times. The expected annual private direct medical cost of the baseline case was US$187 (95% CI 135 to 258) for a 65-year-old man without complications. Heart disease, stroke, sight-threatening diabetic retinopathy and end-stage renal disease increased the private medical costs by 1.5 to 2.5 times. CONCLUSIONS: Wide variations in direct medical cost in event year and subsequent years across different major complications were observed. Input of these data would be essential for economic evaluations of diabetes management programmes.


Assuntos
Complicações do Diabetes/economia , Complicações do Diabetes/epidemiologia , Custos de Cuidados de Saúde , Saúde Pública/economia , Idoso , Estudos Transversais , Angiopatias Diabéticas/economia , Angiopatias Diabéticas/epidemiologia , Nefropatias Diabéticas/economia , Nefropatias Diabéticas/epidemiologia , Retinopatia Diabética/economia , Retinopatia Diabética/epidemiologia , Feminino , Hong Kong/epidemiologia , Humanos , Falência Renal Crônica/economia , Falência Renal Crônica/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/economia , Infarto do Miocárdio/epidemiologia , Acidente Vascular Cerebral/economia , Acidente Vascular Cerebral/epidemiologia
7.
Eur J Clin Nutr ; 71(7): 870-880, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28378847

RESUMO

There has been a marked increase in the prevalence of diabetes in Asia, including China, over the last few decades. While the increased prevalence of diabetes has often been attributed to the nutritional transition associated with recent economic development, emerging data suggest that early-life exposures also play a major role in shaping developmental trajectories, and contributes to alter an individual's susceptibility to diabetes and other non-communicable diseases (NCDs). Early-life exposures such as in utero exposure to undernutrition has been consistently linked with later risk of diabetes and obesity. Furthermore, in utero exposure to maternal hyperglycemia, maternal obesity and excess gestational weight gain are all linked with increased childhood obesity and later risk of diabetes. Emerging data have also highlighted the potential link between early-feeding practices, the role of one-carbon metabolism in metabolic programming and endocrine disrupting chemicals (EDCs) with later risk of diabetes. These different developmental exposures may all be highly relevant to the current epidemic of diabetes in China. For example, the prevalence of gestational diabetes has increased markedly over the last two decades, and may contribute to the diabetes epidemic by driving macrosomia, childhood obesity and later risk of diabetes. In order to address the current burden of diabetes, a lifecourse perspective, incorporating multisectoral efforts from public health policy down to the individuals, will be needed. Several major initiatives have been launched in China as part of its national plans for NCD prevention and treatment, and the experience from these efforts would be invaluable.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Gestacional/epidemiologia , Desnutrição/epidemiologia , Fenômenos Fisiológicos da Nutrição Materna , Obesidade/epidemiologia , Complicações na Gravidez/epidemiologia , China/epidemiologia , Dieta , Feminino , Comportamentos Relacionados com a Saúde , Política de Saúde , Humanos , Estilo de Vida , Metanálise como Assunto , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Prevalência , Saúde Pública , Fatores de Risco
8.
Diabetes Metab ; 42(6): 424-432, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27568125

RESUMO

AIM: To evaluate the effectiveness of the multidisciplinary Risk Assessment and Management Program for Patients with Diabetes Mellitus (RAMP-DM) in reducing the risks of microvascular complications. METHODS: This prospective cohort study was conducted with 29,670 propensity-score-matched RAMP-DM participants and diabetes patients under the usual primary care (14,835 in each group). Study endpoints were the first occurrence of any diabetic microvascular complications, non-proliferative diabetic retinopathy/preproliferative diabetic retinopathy (NPDR/prePDR), sight-threatening diabetic retinopathy (STDR) or blindness, nephropathy, end-stage renal disease (ESRD), neuropathy and lower-limb ulcers or amputation. Log-rank tests and multivariable Cox proportional-hazards regressions were employed to estimate between-group differences in incidences of study endpoints. RESULTS: After a median follow-up of 36 months with>41,000 person-years in each group, RAMP-DM participants had a lower incidence of microvascular complications (760 vs 935; adjusted hazard ratio [HR]: 0.73; 95% confidence interval [CI]: 0.66-0.81; P<0.001) and lower incidences of all specific microvascular complications except neuropathy (adjusted HR: 0.94; 95% CI: 0.61-1.45; P=0.778). Adjusted HRs for the RAMP-DM vs control group for ESRD, STDR or blindness, and lower-limb ulcers or amputation were 0.40 (95% CI: 0.24-0.69; P<0.001), 0.55 (95% CI: 0.39-0.78; P=0.001) and 0.49 (95% CI: 0.30-0.80; P=0.005), respectively. CONCLUSION: The RAMP-DM intervention was associated with lower incidences of all microvascular complications except neuropathy over a 3-year follow-up. These encouraging results constitute evidence that structured risk assessment and risk-stratified management provided by a multidisciplinary team is effective for reducing microvascular complications in diabetes patients. CLINICAL TRIAL REGISTRY: NCT02034695, www.ClinicalTrials.gov.


Assuntos
Angiopatias Diabéticas , Idoso , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/prevenção & controle , Angiopatias Diabéticas/terapia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco
10.
Eur J Surg Oncol ; 41(6): 758-65, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25680952

RESUMO

BACKGROUND: Rapid rise in differentiated thyroid cancer (DTC) may impose a heavy economic burden on future healthcare. We aimed to calculate the average first-year monetary cost/patient for DTC and estimate the projected cost burden on our local healthcare system. METHODS: Medical records of 270 clinically-relevant DTC patients were reviewed to calculate the amount of services utilized during the first-year. Only direct costs were included with estimates derived from government gazette. Cancer incidences were derived from the territory-wide cancer registry. Total annual cost equaled to the incidence multiplied by the cost/patient. RESULTS: The average first-year cost of DTC was USD11,560/patient. Initial surgery accounted for 66.9% of total cost. Male and female annual percentage increases for DTC were 4.86% and 4.28%, respectively. Female DTC is projected to surpass rectal cancer in 2019 (20.4/100,000 vs. 20.0/100,000) and colon cancer (47.2/100,000 vs. 46.8/100,000) in 2039. However, the projected incidence of DTC in 2026 would still be about one fourth that of CRC (19.5/100,000 vs. 83.2/100,000). CONCLUSIONS: The average first-year monetary cost of DTC care was relatively low. Initial surgery accounted for most of the cost. Despite a rapid incidence rise, the projected first-year cost for DTC is unlikely to impose substantial economic burden on our local future healthcare system.


Assuntos
Custos de Cuidados de Saúde/estatística & dados numéricos , Serviços de Saúde/economia , Neoplasias da Glândula Tireoide/economia , Adulto , Idoso , Custos Diretos de Serviços , Feminino , Serviços de Saúde/estatística & dados numéricos , Hong Kong/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Fatores Sexuais , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/terapia , Tireoidectomia/economia
13.
Environ Int ; 35(7): 1040-7, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19535140

RESUMO

Nine groups of food items (freshwater fish, marine fish, pork, chicken, chicken eggs, leafy, non-leafy vegetables, rice and flour) and three types of human samples (human milk, maternal serum and cord serum) were collected for the analysis of PCDD/Fs. Results of chemical analysis revealed PCDD/Fs concentrations (pg g(-1) fat) in the following ascending order: pork (0.289 pg g(-1) fat), grass carp (Ctenopharyngodon idellus) (freshwater fish) (0.407), golden thread (Nemipterus virgatus) (marine fish) (0.511), chicken (0.529), mandarin fish (Siniperca kneri) (marine fish) (0.535), chicken egg (0.552), and snubnose pompano (Trachinotus blochii) (marine fish) (1.219). The results of micro-EROD assay showed relatively higher PCDD/Fs levels in fish (2.65 pg g(-1) fat) when compared with pork (0.47), eggs (0.33), chicken (0.13), flour (0.07), vegetables (0.05 pg g(-1) wet wt) and rice (0.05). The estimated average daily intake of PCDD/Fs of 3.51 pg EROD-TEQ/kg bw/day was within the range of WHO Tolerable Daily Intake (1-4 pg WHO-TEQ/kg bw/day) and was higher than the Provisional Tolerable Daily Intake (PMTL) (70 pg for dioxins and dioxin-like PCBs) recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) [Joint FAO/WHO Expert Committee on Food Additives (JECFA), Summary and conclusions of the fifty-seventh meeting, JECFA, 2001.]. Nevertheless, the current findings were significantly lower than the TDI (14 pg WHO-TEQ/kg/bw/day) recommended by the Scientific Committee on Food of the Europe Commission [European Scientific Committee on Food (EU SCF), Opinions on the SCF on the risk assessment of dioxins and dioxin-like PCBs in food, 2000.]. However, it should be noted that micro-EROD assay overestimates the PCDD/Fs levels by 2 to 7 folds which may also amplify the PCDD/Fs levels accordingly. Although the levels of PCDD/Fs obtained from micro-EROD assay were much higher than those obtained by chemical analysis by 2 to 7 folds, it provides a cost-effective and rapid screening of dioxin levels in food and human samples.


Assuntos
Benzofuranos/análise , Poluentes Ambientais/análise , Análise de Alimentos , Dibenzodioxinas Policloradas/análogos & derivados , Benzofuranos/sangue , Benzofuranos/metabolismo , Biomarcadores/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Dibenzofuranos Policlorados , Dioxinas/análise , Dioxinas/metabolismo , Ovos/análise , Poluentes Ambientais/sangue , Poluentes Ambientais/metabolismo , Feminino , Sangue Fetal/química , Farinha/análise , Hong Kong , Humanos , Carne/análise , Leite Humano/química , Oryza/química , Dibenzodioxinas Policloradas/análise , Dibenzodioxinas Policloradas/sangue , Dibenzodioxinas Policloradas/metabolismo , Medição de Risco , Verduras/química
14.
Theor Appl Genet ; 116(6): 815-24, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18219476

RESUMO

Oil palm (Elaeis guineensis Jacq.) requires 19 years per cycle of phenotypic selection. The use of molecular markers may reduce the generation interval and the cost of oil-palm breeding. Our objectives were to compare, by simulation, the response to phenotypic selection, marker-assisted recurrent selection (MARS), and genomewide selection with small population sizes in oil palm, and assess the efficiency of each method in terms of years and cost per unit gain. Markers significantly associated with the trait were used to calculate the marker scores in MARS, whereas all markers were used (without significance tests) to calculate the marker scores in genomewide selection. Responses to phenotypic selection and genomewide selection were consistently greater than the response to MARS. With population sizes of N = 50 or 70, responses to genomewide selection were 4-25% larger than the corresponding responses to phenotypic selection, depending on the heritability and number of quantitative trait loci. Cost per unit gain was 26-57% lower with genomewide selection than with phenotypic selection when markers cost US $1.50 per data point, and 35-65% lower when markers cost $0.15 per data point. With population sizes of N = 50 or 70, time per unit gain was 11-23 years with genomewide selection and 14-25 years with phenotypic selection. We conclude that for a realistic yet relatively small population size of N = 50 in oil palm, genomewide selection is superior to MARS and phenotypic selection in terms of gain per unit cost and time. Our results should be generally applicable to other tree species that are characterized by long generation intervals, high costs of maintaining breeding plantations, and small population sizes in selection programs.


Assuntos
Arecaceae/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Genoma de Planta , Seleção Genética , Simulação por Computador , Marcadores Genéticos , Modelos Genéticos , Fenótipo , Locos de Características Quantitativas
15.
Adv Clin Chem ; 36: 63-107, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11605260

Assuntos
Apoptose , Humanos
16.
Artif Intell Med ; 22(3): 249-60, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11377150

RESUMO

We present a new stochastic learning algorithm and first results of computational experiments on fragments of liver CT images. The algorithm is designed to compute a depth-three threshold circuit, where the first layer is calculated by an extension of the Perceptron algorithm by a special type of simulated annealing. The fragments of CT images are of size 119x119 with eight bit grey levels. From 348 positive (focal liver tumours) and 348 negative examples a number of hypotheses of the type w(1)x(1)+. . .;+w(n)x(n)>/=theta were calculated for n=14161. The threshold functions at levels two and three were determined by computational experiments. The circuit was tested on various sets of 50+50 additional positive and negative examples. For depth-three circuits, we obtained a correct classification of about 97%. The input to the algorithm is derived from the DICOM standard representation of CT images. The simulated annealing procedure employs a logarithmic cooling schedule c(k)=Gamma/ln(k+2), where Gamma is a parameter that depends on the underlying configuration space. In our experiments, the parameter Gamma is chosen according to estimations of the maximum escape depth from local minima of the associated energy landscape.


Assuntos
Algoritmos , Inteligência Artificial , Neoplasias Hepáticas/diagnóstico , Modelos Teóricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Humanos , Cadeias de Markov , Software
17.
Arch Environ Contam Toxicol ; 38(4): 486-93, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10787100

RESUMO

The aim of the present project is to determine the feasibility of measuring hepatic cytochrome P4501A1 (CYP1A1) and metallothionein (MT) mRNA in fish as an integrative measurement of persistent organic pollutants (POPs) and heavy metal contamination in sediment arising in Hong Kong. Sediment samples were collected from different sites, including Victoria Harbour (VS6), Yim Tin Tsai (YTT) at Tolo Harbour, Mai Po marshes (MPM) at Deep Bay, and Southern Waters (SS6) of coastal waters. The samples were analyzed for total and extractable concentrations of Cd, Cu, Ni, Zn, and Pb, as well as PCBs and PAHs. In addition, biomarker responses were studied in tilapia exposed experimentally to coastal sediment for 7 days. Using RT-PCR technique, hepatic CYP1A1 and MT mRNA were measured. Three control groups were used, including one negative control group maintained in sea water only; the second and third positive control groups were in sea water but were intraperitoneally injected with either beta-naphthoflavone (40 microg/g body weight) or cadmium chloride (10 microg/g body weight), respectively. The chemical data showed that VS6, YTT, and MPM were classified as Class C sediment according to the sediment quality criteria defined by the Hong Kong Environmental Protection Department, indicating the sites were heavily polluted. The exposure of tilapia to the sediment induced hepatic CYP1A1 (VS6 > YTT > MPM > SS6) and MT (VS6 > MPM > YTT > SS6) levels. The induction patterns were comparable to the levels of POPs and metal contamination in the sediment, indicating that the biomarker responses could be used to differentiate low to high levels of contamination among sediment.


Assuntos
Sedimentos Geológicos/química , Metais Pesados/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Animais , Cloreto de Cádmio/toxicidade , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , DNA/análise , Primers do DNA/química , Estudos de Avaliação como Assunto , Hong Kong , Fígado/enzimologia , Metalotioneína/genética , Metalotioneína/metabolismo , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tilápia/metabolismo , beta-Naftoflavona/toxicidade
18.
Arch Environ Contam Toxicol ; 32(3): 260-7, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9096074

RESUMO

The main aim of the present project is to study the feasibility of using different trophic organisms for evaluating the toxicity of dredged sediments arising in Hong Kong. A total of eight sediment samples (duplicate samples collected from four selected sites: Kowloon Bay, Tsing Yi,Chek Lap Kok, and Double Haven) of Hong Kong coastal waters were analyzed for the total concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn, total organic carbon, acid volatile sulfides, simultaneously extracted metals, redox potential, and 12 organic micropollutants. The sediment elutriates were also analysed for the various metal concentrations, as well as contents of ammonia-N, nitrate, total sulfide, sulfate, and total organic carbon. Elutriate Sediment Toxicity Tests (ESTT) were also conducted, using two microalgae (Skeletonema costatum, a diatom and Dunaliella tertiolecta, a flagellate), juvenile shrimp (Metapenaeus ensis) and juvenile fish (Trachinotus obtaus). Two commercially available tests using bacteria (Microtox Test and Toxi-Chromotest) also were employed to test both the solid phase and elutriates of the sediments. The results of Microtox test on the solid phase, and bioassay tests using diatom on the sediment elutriate, especially the former, were correlated significantly (p < 0.05) with a number of physico-chemical properties of sediments and elutriates. It is recommended that a combination of a liquid-phase bioassay using diatom and a solid-phase bioassay using Microtox test should be used for screening a large number of sediment samples. However, the presence of ammonia in the sediments containing a high content of organic matter seemed to interfere the detection of contamination impacts.


Assuntos
Sedimentos Geológicos , Poluentes Químicos da Água/toxicidade , Animais , Bioensaio , Decápodes , Feminino , Peixes
19.
Int J Health Serv ; 26(1): 67-92, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8932602

RESUMO

This article employs case studies of China and Hong Kong to question the western ethnocentric construction of the welfare state that predominates in comparative social policy research. The authors argue that welfare regimes, and particularly the "welfare state," have been constructed as capitalist-democratic projects and that this has the damaging effect of excluding from analyses not only several advanced capitalist societies in the Asian-Pacific area but also the world's most populous country. If welfare state regimes can only coexist with western political democracies, then China and Hong Kong are excluded automatically. A similar result occurs if the traditional social administration approach is adopted whereby a "welfare state" is defined in terms only of direct state provision. The authors argue that such assumptions are untenable if state welfare is to be analyzed as a universal phenomenon. Instead of being trapped within an ethnocentric welfare statism, what social policy requires is a global political economy perspective that facilitates comparisons of the meaning of welfare and the state's role in producing it north, south, east and west.


Assuntos
Política de Saúde , Sistemas Políticos , Seguridade Social , Medicina Estatal/organização & administração , China , Democracia , Países Desenvolvidos , Pesquisa sobre Serviços de Saúde , Hong Kong , Humanos , Investimentos em Saúde , Variações Dependentes do Observador , Socialismo
20.
Eur Heart J ; 11(3): 219-24, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2318225

RESUMO

The haemodynamics and myocardial lactate consumption during induced atrial fibrillation (AF) were studied in 10 patients with paroxysmal AF. Their mean age (+/- SD) was 61 +/- 5 years and none had clinical evidence of ischaemic or rheumatic heart disease. Compared with sinus rhythm, the onset of AF was associated with a reduction in systolic blood pressure (152 +/- 13 mmHg) in AF vs 169 +/- 23 mmHg in sinus rhythm, P less than 0.01). There was no consistent change in cardiac output at the onset of AF compared with sinus rhythm, but the cardiac output was lower compared with regular atrial pacing at rates similar to those of induced AF (3.85 +/- 0.76 vs 4.38 +/- 0.89 l min-1, P less than 0.02). Compared with sinus rhythm or rate-matched atrial pacing, AF was associated with an elevated pulmonary arterial pressure (24.2 +/- 5.6 mmHg in AF vs 17.9 +/- 14.4 mmHg in sinus rhythm, P less than 0.01) and pulmonary arterial wedge pressure (18.6 +/- 5.6 vs 9.7 +/- 3.9 mmHg, P less than 0.01). The haemodynamic changes during AF were similar to those seen during regular ventricular pacing at an equivalent rate, although the latter was associated with a lower systolic blood pressure (152 +/- 13 mmHg in AF vs 136 +/- 25 mmHg in ventricular pacing, P less than 0.05) and higher right atrial pressure (8.2 +/- 4.4 vs 11.5 +/- 7.5 mmHg respectively, P less than 0.05), presumably due to the deleterious effects of cannon 'a' waves.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Fibrilação Atrial/fisiopatologia , Pressão Sanguínea/fisiologia , Débito Cardíaco/fisiologia , Idoso , Feminino , Hemodinâmica/fisiologia , Humanos , Lactatos/metabolismo , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo , Artéria Pulmonar/fisiologia
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