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1.
Neth Heart J ; 29(11): 557-565, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34232481

RESUMO

Recently, the European Society of Cardiology (ESC) has updated its guidelines for the management of patients with acute coronary syndrome (ACS) without ST-segment elevation. The current consensus document of the Dutch ACS working group and the Working Group of Interventional Cardiology of the Netherlands Society of Cardiology aims to put the 2020 ESC Guidelines into the Dutch perspective and to provide practical recommendations for Dutch cardiologists, focusing on antiplatelet therapy, risk assessment and criteria for invasive strategy.

2.
Philos Trans A Math Phys Eng Sci ; 379(2202): 20190438, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34092105

RESUMO

This paper investigates large fluctuations of locational marginal prices (LMPs) in wholesale energy markets caused by volatile renewable generation profiles. Specifically, we study events of the form [Formula: see text] where LMP is the vector of LMPs at the n power grid nodes, and α-, [Formula: see text] are vectors of price thresholds specifying undesirable price occurrences. By exploiting the structure of the supply-demand matching mechanism in power grids, we look at LMPs as deterministic piecewise affine, possibly discontinuous functions of the stochastic input process, modelling uncontrollable renewable generation. We use techniques from large deviations theory to identify the most likely ways for extreme price spikes to happen, and to rank the nodes of the power grid in terms of their likelihood of experiencing a price spike. Our results are derived in the case of Gaussian fluctuations, and are validated numerically on the IEEE 14-bus test case. This article is part of the theme issue 'The mathematics of energy systems'.

3.
Neth Heart J ; 28(3): 131-135, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31696408

RESUMO

An early invasive strategy in patients who have acute coronary syndrome without ST-elevation (NSTE-ACS) can improve clinical outcome in high-risk subgroups. According to the current guidelines of the European Society of Cardiology (ESC), the majority of NSTE-ACS patients are classified as "high-risk". We propose to prioritise patients with a global registry of acute coronary events (GRACE) risk score >140 over patients with isolated troponin rise or electrocardiographic changes and a GRACE risk score <140. We also acknowledge that same-day transfer for all patients at a high risk is not necessary in the Netherlands since the majority of Dutch cardiology departments are equipped with a catheterisation laboratory where diagnostic coronary angiography is routinely performed in NSTE-ACS patients. Therefore, same-day transfer should be restricted to true high-risk patients (in addition to those NSTE-ACS patients with very high-risk (VHR) criteria) in centres without coronary angiography capabilities.

4.
Neth Heart J ; 25(12): 655-663, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28762022

RESUMO

To prevent recurrent ischaemic events, dual antiplatelet therapy (DAPT) is the standard of care after percutaneous coronary intervention and in the treatment of acute coronary syndrome. Recent evidence supports an adjusted DAPT duration in selected patients.The current paper aims to encourage cardiologists to actively search for patients benefiting from either shorter or prolonged duration DAPT and proposes an algorithm to identify patients who are likely to benefit from such an alternative strategy.Individualised DAPT duration should be considered in high-risk anatomic and/or clinical subgroups or in patients at increased haemorrhagic risk with low ischaemic risk. Both thrombotic and haemorrhagic risk should be assessed in all patients. In patients undergoing percutaneous coronary intervention, the interventional cardiologist could advise on the minimal duration of DAPT. However, in contrast to the minimum duration of DAPT for stent thrombosis prevention, longer duration DAPT is aimed at prevention of spontaneous myocardial infarction, and not at stent thrombosis, and thus the key to success is to treat the patient's overall thrombotic risk.The advice on the duration of DAPT must be documented in the patient's records and communicated with the treating physician and general practitioner. DAPT duration should be reassessed at least on a yearly basis.

5.
Neth Heart J ; 25(7-8): 455-460, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28236041

RESUMO

BACKGROUND: Since it was anticipated that the need for doctors would increase due to demographic changes, the number of positions for medical specialty training programs has increased from the year 2000 onwards. However, the number of permanent positions for young cardiologists did not follow that trend leading to concerns about future employment. Therefore, the aim of the current study was to assess short-term career perspectives of young cardiologists in the Netherlands. METHODS: All cardiologists who ended their training between 1 January 2011 and 31 December 2014 were invited to fill in a questionnaire about their first employment status and were followed yearly until the participant had a permanent position. The timespan between the end of training and the moment of permanent employment was assessed. Furthermore, the association between professional profile and short-term career perspectives was investigated. RESULTS: The observed unemployment was 1.6% and lasted less than a year in all cases. Of the participants, 77% started their career with a temporary contract; within four years this was 7%. Of young cardiologists, 46% started their career as a fellow and 24% as an attending physician. A total of 29% of male cardiologists started their career with a permanent contract as compared with 12% of females (p = 0.01). Within two years this difference was no longer observed. CONCLUSIONS: Unemployment is low among young cardiologists. Most cardiologists start their career with a temporary contract. The time to a permanent contract is slightly longer for female cardiologists as compared with males.

6.
Neth J Med ; 72(10): 551-3, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26219763

RESUMO

A 62-year-old patient with peritoneal dialysis (PD)-associated peritonitis is described. Identical strains of Pasteurella multocida and Streptococcus minor were cultured from the dialysate, and from the saliva of her recently adopted stray cat. Pasteurella is not often encountered as pathogen in PD-associated peritonitis, Streptococcus minor has never been cultured in human infection before. We emphasise the importance of hygiene in peritoneal dialysis and the need for testing pets when zoonotic pathogens are cultured.


Assuntos
Infecções por Pasteurella/microbiologia , Pasteurella multocida/isolamento & purificação , Peritonite/microbiologia , Infecções Estreptocócicas/microbiologia , Streptococcus/classificação , Zoonoses/microbiologia , Animais , Antibacterianos/administração & dosagem , Doenças do Gato/microbiologia , Doenças do Gato/transmissão , Gatos , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Pasteurella/tratamento farmacológico , Infecções por Pasteurella/transmissão , Diálise Peritoneal , Peritonite/tratamento farmacológico , Saliva/microbiologia , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/transmissão , Streptococcus/isolamento & purificação , Combinação Trimetoprima e Sulfametoxazol/administração & dosagem , Zoonoses/transmissão
7.
Eur J Trauma Emerg Surg ; 37(4): 373-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21949543

RESUMO

PURPOSE OF THE STUDY: To evaluate the value of a pelvic X-ray compared to clinical examination in diagnosing pelvic ring fractures, using computed tomography (CT) as the gold standard, in alert [Glasgow Coma Scale (GCS) ≥ 13] adult blunt trauma patients in the emergency room. METHODS: A systematic literature search was performed in PubMed and Embase. The results were screened on their titles and abstracts using in- and exclusion criteria. Subsequently, the selected articles were critically appraised for their relevance and validity. RESULTS: Two studies investigating the diagnostic value of clinical examination and pelvic X-ray compared to CT were identified. Both studies demonstrate higher negative predictive values for clinical examination [0.99 (95% confidence interval [CI] 0.98-1.0) and 1.0 (95% CI 0.99-1.0)] compared to the negative predictive values of pelvic X-ray [0.98 (95% CI 0.93-0.99) and 0.99 (95% CI 0.99-1.0)]. The positive predictive values for clinical examination were low [0.18 (95% CI 0.16-0.23) and 0.35 (95% CI 0.30-0.42)] compared to pelvic X-ray [0.97 (95% CI 0.96-0.98) and 0.97 (95% CI 0.90-0.99)]. CONCLUSIONS: In alert blunt trauma patients, pelvic X-ray only has additional diagnostic value for the detection of pelvic ring fractures if the clinical examination is positive. Pelvic X-ray should not be performed if the clinical examination is negative. In this manner, the expenditure of time, costs, and radiation are optimized.

8.
J Thromb Haemost ; 8(11): 2385-93, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20831622

RESUMO

BACKGROUND: Early coronary stent thrombosis occurs most frequent after primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). OBJECTIVES: To identify the specific predictors of, respectively, acute and subacute stent thrombosis in patients after primary PCI for STEMI. PATIENTS/METHODS: Consecutive STEMI patients with angiographically confirmed early stent thrombosis were enrolled and compared in a 2 : 1 ratio with a matched control group. Clinical outcome was collected up to 1 year. RESULTS: Of 5842 STEMI patients treated with primary PCI, 201 (3.5%) presented with a definite early stent thrombosis. Of these, 97 (1.7%) had acute stent thromboses and 104 (1.8%) had subacute stent thromboses. Postprocedurally discovered dissection, undersizing and smaller stent diameter were the strongest predictors for acute stent thrombosis. No glycoprotein IIb/IIIa therapy and the use of drug-eluting stents were also associated with acute stent thrombosis. Lack of clopidogrel therapy in the first 30 days after the index PCI was the strongest predictor for subacute stent thrombosis. Mortality rates at 1-year follow-up were lower for acute stent thrombosis than for subacute stent thrombosis (8.3% vs. 13.2%, P = 0.294). The incidence of definite recurrent stent thrombosis at 1-year follow up was significantly lower after a first definite acute stent thrombosis than after a first definite subacute stent thrombosis (6.4% vs. 19.3%, P = 0.007 at 1 year). CONCLUSIONS: The specific risk factors for, respectively, acute and subacute stent thrombosis after primary PCI vary greatly. Mortality rates are high for both categories of stent thrombosis. However, recurrent stent thrombosis occurs more frequently after subacute stent thrombosis.


Assuntos
Angioplastia Coronária com Balão/métodos , Infarto do Miocárdio/terapia , Trombose/complicações , Trombose/etiologia , Idoso , Clopidogrel , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Países Baixos , Inibidores da Agregação Plaquetária/uso terapêutico , Sistema de Registros , Fatores de Risco , Stents/efeitos adversos , Trombose/terapia , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico , Resultado do Tratamento
9.
Occup Environ Med ; 66(4): 211-20, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19017690

RESUMO

This paper systematically reviews the scientific literature on the effects of individual and work-related factors on the Work Ability Index (WAI). Studies on work ability published from 1985 to 2006 were identified through a structured search in PubMed, and Web of Science. Studies were included if the WAI was used as measure of work ability and if quantitative information was presented on determinants of work ability. In total, 20 studies were included with 14 cross-sectional studies and six longitudinal studies. Factors associated with poor work ability, as defined by WAI, were lack of leisure-time vigorous physical activity, poor musculoskeletal capacity, older age, obesity, high mental work demands, lack of autonomy, poor physical work environment, and high physical work load. The WAI is associated with individual characteristics, lifestyle, demands at work, and physical condition. This multifactorial nature of work ability should be taken into account in health promotion programmes aimed at maintaining and promoting the participation of the labour force and improvement of the performance at work.


Assuntos
Avaliação da Capacidade de Trabalho , Adulto , Aptidão , Estudos Transversais , Emprego , Feminino , Humanos , Estilo de Vida , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Aptidão Física , Fatores de Risco , Trabalho , Carga de Trabalho , Local de Trabalho
10.
Occup Med (Lond) ; 52(4): 177-81, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12091582

RESUMO

The goal of the study was to assess the test-retest reliability of the Work Ability Index (WAI) questionnaire. Reliability was tested using a test-retest design with a 4 week interval between measurements. Valid data were collected among 97 elderly construction workers aged 40 years and older. We analysed the test-retest reliability of the WAI score itself (range 7-49 points) and classification in one of the four WAI categories based on this score: poor (7-27 points); moderate (28-36 points); good (37-43 points); and excellent work ability (44-49 points). Exactly the same WAI score on both measurements was reported by 25% of the subjects and 95% of the individual differences between measurements were found to be <6.86 points (two times standard deviation). Despite the individual changes between measurements, no significant difference was reported in the mean WAI score at group level between test and retest measurements (40.4 versus 39.9). The percentage of observed agreement for the classification of subjects in one of the four WAI categories on both measurements equalled 66%. The results of this study provided evidence of an acceptable test-retest reliability of the classification of subject's work ability by means of the WAI questionnaire. At group level, the mean WAI score and classification into WAI categories were found to be a stable measure over a 4 week interval. These results give additional support for the applicability of the questionnaire in occupational health research and the daily practice of occupational health care.


Assuntos
Avaliação da Capacidade de Trabalho , Adulto , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Saúde Ocupacional , Reprodutibilidade dos Testes , Inquéritos e Questionários
11.
Occup Environ Med ; 59(6): 356-61, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12040108

RESUMO

OBJECTIVES: Building on Karasek's model of job demands and control (JD-C model), this study examined the effects of job control, quantitative workload, and two occupation specific job demands (physical demands and supervisor demands) on fatigue and job dissatisfaction in Dutch lorry drivers. METHODS: From 1181 lorry drivers (adjusted response 63%) self reported information was gathered by questionnaire on the independent variables (job control, quantitative workload, physical demands, and supervisor demands) and the dependent variables (fatigue and job dissatisfaction). Stepwise multiple regression analyses were performed to examine the main effects of job demands and job control and the interaction effect between job control and job demands on fatigue and job dissatisfaction. RESULTS: The inclusion of physical and supervisor demands in the JD-C model explained a significant amount of variance in fatigue (3%) and job dissatisfaction (7%) over and above job control and quantitative workload. Moreover, in accordance with Karasek's interaction hypothesis, job control buffered the positive relation between quantitative workload and job dissatisfaction. CONCLUSIONS: Despite methodological limitations, the results suggest that the inclusion of (occupation) specific job control and job demand measures is a fruitful elaboration of the JD-C model. The occupation specific JD-C model gives occupational stress researchers better insight into the relation between the psychosocial work environment and wellbeing. Moreover, the occupation specific JD-C model may give practitioners more concrete and useful information about risk factors in the psychosocial work environment. Therefore, this model may provide points of departure for effective stress reducing interventions at work.


Assuntos
Condução de Veículo/psicologia , Fadiga/etiologia , Satisfação no Emprego , Doenças Profissionais/psicologia , Estresse Psicológico/etiologia , Adulto , Idoso , Emprego/psicologia , Feminino , Humanos , Controle Interno-Externo , Relações Interpessoais , Masculino , Pessoa de Meia-Idade , Países Baixos , Esforço Físico/fisiologia , Análise de Regressão , Carga de Trabalho
12.
J Immunol ; 167(2): 647-54, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11441067

RESUMO

Human serum amyloid P component (SAP) is a glycoprotein structurally belonging to the pentraxin family of proteins, which has a characteristic pentameric organization. Mice with a targeted deletion of the SAP gene develop antinuclear Abs, which was interpreted as evidence for a role of SAP in controlling the degradation of chromatin. However, in vitro SAP also can bind to phosphatidylethanolamine, a phospholipid which in normal cells is located mainly in the inner leaflet of the cell membrane, to be translocated to the outer leaflet of the cell membrane during a membrane flip-flop. We hypothesized that SAP, because of its specificity for phosphatidylethanolamine, may bind to apoptotic cells independent of its nuclear binding. Calcium-dependent binding of SAP to early, nonpermeable apoptotic Jurkat, SKW, and Raji cells was indeed observed. Experiments with flip-flopped erythrocytes confirmed that SAP bound to early apoptotic cells via exposed phosphatidylethanolamine. Binding of SAP was stronger to late, permeable apoptotic cells. Experiments with enucleated neutrophils, with DNase/RNase treatment of late apoptotic Jurkat cells, and competition experiments with histones suggested that binding of SAP to late apoptotic cells was largely independent of chromatin. Confocal laser microscopic studies indeed suggested that SAP bound to these apoptotic cells mainly via the blebs. Thus, this study shows that SAP binds to apoptotic cells already at an early stage, which raises the possibility that SAP is involved in dealing with apoptotic cells in vivo.


Assuntos
Apoptose , Cromatina/fisiologia , Componente Amiloide P Sérico/metabolismo , Animais , Apoptose/efeitos dos fármacos , Ligação Competitiva , Bovinos , Ácido Edético/farmacologia , Membrana Eritrocítica/metabolismo , Humanos , Células Jurkat , Ligantes , Neutrófilos/metabolismo , Plasma/metabolismo , Ligação Proteica/efeitos dos fármacos , Componente Amiloide P Sérico/isolamento & purificação , Fatores de Tempo , Células Tumorais Cultivadas
13.
Int Arch Occup Environ Health ; 74(1): 21-30, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11196077

RESUMO

OBJECTIVES: This study analysed the association between gender and upper extremity musculoskeletal complaints, among the general working population and in various occupational groups. The hypothesis was tested whether the higher risk for women in the general working population for these complaints could partly be explained by differences in the distribution of men and women in occupations with different risks for the onset of upper extremity musculoskeletal complaints. METHODS: The data for this study came from cross-sectional questionnaire data from 16,874 employees categorised in 21 different occupational classes. Associations between gender and complaints of the upper extremities were analysed for the total study sample and for each occupational class separately. An adjustment was made for the variable 'occupational class' in the final model in order to study the impact of occupational gender segregation on gender differences in upper extremity complaints in the working population. RESULTS: In the total study sample, significantly higher risks of complaints of the neck, shoulder, elbow, and wrist among the women were observed. Within many occupational classes, women reported significantly higher risks than did men, in particular for complaints of the neck and shoulder. Adjustment for occupational class showed increased risks for female workers for complaints of the neck, shoulder, elbow, and wrist, hence, rejecting our hypothesis on occupational gender segregation as an explanation for the higher risks for upper extremity complaints among women in the general working population. CONCLUSIONS: This study confirmed the presence of gender differences in upper extremity musculoskeletal complaints among the working population and in many occupational classes, with female workers having the higher risk. The results, however, do not lend support to a differential occupational exposure theory as an explanation for the higher risks for these complaints among women in the general working population. Careful consideration of gender influence in ergonomic epidemiological studies is recommended.


Assuntos
Doenças Musculoesqueléticas/fisiopatologia , Doenças Profissionais/fisiopatologia , Fatores Sexuais , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Musculoesqueléticas/epidemiologia , Países Baixos/epidemiologia , Doenças Profissionais/epidemiologia , Vigilância da População , Prevalência , Inquéritos e Questionários
15.
J Virol ; 74(4): 1712-7, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10644341

RESUMO

Previously, we and others have demonstrated that the process of reverse transcription of human immunodeficiency virus type 1 (HIV-1) is disturbed in nondividing macrophages and quiescent T lymphocytes. Here we analyzed which phase of the cell cycle in macrophages is crucial for early steps in the HIV-1 replication cycle. HIV-1 Ba-L-inoculated macrophages arrested early in the G(1) phase by n-butyrate contained incomplete products of reverse transcription. In gamma-irradiated macrophages, reverse transcription was successfully completed but proviral integration could not be detected. In these cells, nuclear import was disturbed as reflected by the absence of two-long-terminal-repeat circles. In macrophages arrested late in G(1) phase by aphidicolin or 5, 6-dichloro-1-beta-D-ribofuranosyl-benzimidazole (DRB), reverse transcription was unaffected. Proviral integration occurred efficiently in DRB-treated macrophages, whereas integrated proviral DNA could not be detected after aphidicolin treatment. Arrest at G(2) phase of the cell cycle by nocodazole did not affect reverse transcription or proviral integration. Treatment of macrophages with hydroxyurea (HU), which reduces the intracellular deoxynucleoside triphosphate (dNTP) pool by blocking the de novo synthesis of dNTP, resulted in a dose-dependent inhibition of HIV-1 reverse transcription. This could partially be restored by the addition of nucleoside precursors. Addition of nucleoside precursors enhanced both reverse transcription and cell proliferation. However, the disturbed reverse transcription observed in the nonproliferating and n-butyrate-treated macrophages could not be restored by addition of nucleoside precursors. Similar to observations in quiescent T lymphocytes, incomplete proviral DNA species were arrested in the cytoplasm of the macrophages. Our results indicate that also in primary macrophages the intracellular nucleotide pools and other cellular factors that coincide with late G(1) phase of the cell cycle may contribute to efficient reverse transcription and nuclear localization.


Assuntos
Transcriptase Reversa do HIV/metabolismo , HIV-1/enzimologia , Macrófagos/virologia , Transporte Biológico , Ciclo Celular/efeitos dos fármacos , Divisão Celular , Núcleo Celular/metabolismo , Células Cultivadas , Citoplasma/metabolismo , DNA Viral/metabolismo , Fase G1 , HIV-1/genética , Humanos , Macrófagos/citologia , Provírus/genética , Transcrição Gênica , Integração Viral
16.
Exp Aging Res ; 25(4): 385-91, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10553521

RESUMO

An increase in morbidity and disability rates in the Dutch construction industry is expected due to work force aging. In order to reduce these rates, an occupational health services instrument for senior construction workers will be developed to gather information on present problems in work and health, expectations for the future, and potential preventive policy measures. The aim of this study was to identify age-related work and health issues among construction workers that could be included in the new instrument. Questionnaire data on work and health from 1881 young (16-30 years) and 1946 old (45-64 years) construction workers were analyzed and a literature search was performed. Results show that health problems, in particular for musculoskeletal disorders, increase with advancing age, demonstrating the need for occupational health arrangements for the maintenance and improvement of work ability of senior construction workers.


Assuntos
Envelhecimento/fisiologia , Indústrias , Saúde Ocupacional , Trabalho , Adolescente , Adulto , Inquéritos Epidemiológicos , Humanos , Pessoa de Meia-Idade , Países Baixos , Doenças Profissionais/epidemiologia , Serviços de Saúde do Trabalhador , Prevalência , Inquéritos e Questionários
17.
Ned Tijdschr Geneeskd ; 142(7): 345-8, 1998 Feb 14.
Artigo em Holandês | MEDLINE | ID: mdl-9562740

RESUMO

The weather conditions during the 15th Eleven Cities ice skating marathon (200 kilometers) in Friesland (the Netherlands) on 4 January, 1997, were better than predicted. For measurement of the windchill factor the Steadman scale is preferred to the Siple and Passel scale. For ice skaters the windchill factor is lower than for the spectators, due to the drag effect.


Assuntos
Temperatura Baixa , Hipotermia/fisiopatologia , Patinação/fisiologia , Sensação Térmica/fisiologia , Movimentos do Ar , Humanos , Fatores de Risco
18.
Int J Cancer ; 70(3): 335-40, 1997 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-9033637

RESUMO

CPT-11, a new semisynthetic derivative of camptothecin, is active in a number of tumor types in the clinic, including colon cancer. CPT-11 is a drug that is converted into the active metabolite SN-38 by a carboxylesterase. Experiments were performed to obtain more insight in the cellular characteristics in 5 unselected human colon-cancer cell lines that account for the differential sensitivity to CPT-11 and SN-38. In vitro, the sensitivity to CPT-11 and SN-38 was highest in LS174T and COLO 320 cells, intermediate in SW1398 cells and lowest in COLO 205 and WiDr cells. SN-38 was 130 to 570 times more active than CPT-11. CPT-11 induced complete remissions in 6 out of 12 COLO 320 tumors grown as subcutaneous xenografts, but was not effective in WiDr tumors. The cellular carboxylesterase activity did not relate to the sensitivity to CPT-11. The enzyme activity was higher in normal mouse tissues, i.e., serum and liver, than in COLO 320 or WiDr xenografts, indicating that tumor carboxylesterase is of minor importance for CPT-11 efficacy. The topoisomerase-1 mRNA expression in tumor cells was not predictive of the antiproliferative effects of CPT-11 or SN-38. We observed a positive relationship between the DNA topoisomerase-1 activity and the cellular sensitivity to carboxylesterase-activated CPT-11 (r = 0.75, p < 0.1) as well as to SN-38 (r = 0.89, p < 0.05). The higher topoisomerase-1 activity in COLO 320 cells and tumors when compared with that in WiDr cells and tumors reflected the differences in sensitivity to the drug(s). In conclusion, the DNA topoisomerase-1 activity was the best determinant for CPT-11/SN-38 sensitivity in this panel of unselected human colon-cancer cell lines.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Camptotecina/análogos & derivados , Hidrolases de Éster Carboxílico/metabolismo , Neoplasias do Colo/enzimologia , DNA Topoisomerases Tipo I/metabolismo , Animais , Camptotecina/farmacologia , Carboxilesterase , Neoplasias do Colo/tratamento farmacológico , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Irinotecano , Camundongos , Camundongos Nus , Transplante Heterólogo , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/enzimologia
19.
Int Arch Occup Environ Health ; 70(5): 352-60, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9352339

RESUMO

OBJECTIVES: This cross-sectional study was performed in order to elucidate the relationship of musculoskeletal complaints with age, gender and physically demanding work in the Netherlands. METHODS: Questionnaire data of male (n = 36756) and female (n = 7730) employees, gathered as part of periodical occupational health surveys among active workers in the Netherlands, were stratified for age, gender, and type of work demands. For each stratified group prevalence rates (PR) were calculated for complaints of the back, neck, upper and lower extremities. Moreover, prevalence rate differences (PRD) were estimated as an absolute effect measure of exposure to various types of physical work demands, with active employees in mentally demanding work acting as a reference population. RESULTS: Musculoskeletal complaints among workers in physically demanding occupations were found to increase with age for both sexes. For several complaints, substantially higher rates were reported for women than for men, with a relatively high number of complaints observed among the older female workers (around 40% for complaints of back, upper and lower extremities). Significant PRDs were present in particular for employees in heavy physically demanding occupations and in jobs with mixed mental and physical work demands. CONCLUSIONS: With the ageing of the workforce in mind, these findings stress the need for implementation of preventive measures. Special attention towards the susceptible group of female employees, the elderly age groups in particular, seems justified. In order to clarify the combined effects of age and physical work demands on musculoskeletal complaints, additional studies are required.


Assuntos
Doenças Musculoesqueléticas/epidemiologia , Saúde Ocupacional/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Musculoesqueléticas/etiologia , Países Baixos/epidemiologia , Esforço Físico , Prevalência , Fatores Sexuais , Trabalho
20.
Int J Occup Med Environ Health ; 10(3): 283-95, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9524406

RESUMO

The use of job title as crude exposure measure in epidemiological studies is often inevitable when the available exposure data is scarce. In this study, an existing classification scheme of all job titles in the Netherlands into six categories of physical and mental work demands, constructed by expert judgement, was evaluated. Furthermore, a revision of this classification scheme for a research project on the relation between age, physical work demands, and musculoskeletal complaints was proposed and evaluated as well. For the evaluation, self-reported work demands, derived from questionnaire data of 38,921 employees and quantified by a scale of physical work demands and mental work demands, were used. Based on comparison of the mean scale scores of the several categories of work demands at group level, both classification schemes showed construct validity. Notwithstanding several limitations, the use of the presented classification schemes in epidemiological studies seems particularly challenging and rewarding when analysing data at group level from large and heterogeneous occupational populations. These kind of exploratory studies may generate new hypothesis on the basic patterns concerning work-related disorders, and can also be informative from a policy making perspective.


Assuntos
Descrição de Cargo , Ocupações/classificação , Adolescente , Adulto , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão
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