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1.
Stud Health Technol Inform ; 141: 149-61, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18953135

RESUMO

The Belgian National Health Insurance Institute (NHII) and other Healthcare Authorities intend to improve the quality of care through promoting clinical pathway driven care and by optimising cooperation between the responsible primary care physician and the diabetologist. Patients and healthcare professionals are granted some (financial) benefits when meeting the conditions defined in a mutual agreement.This article describes the conditions and the functional requirements to be met by an EHR to enable and to maximise the benefits of a clinical pathway driven patient care to a specific group of diabetic type 2 patients, based on a mandate issued by the NHII.The generic and specific functional requirements are then translated in test criteria for certification and prioritised in an implementation plan.


Assuntos
Procedimentos Clínicos/organização & administração , Diabetes Mellitus Tipo 2/terapia , Endocrinologia/organização & administração , Sistemas Computadorizados de Registros Médicos/organização & administração , Atenção Primária à Saúde/organização & administração , Protocolos Clínicos , Sistemas de Gerenciamento de Base de Dados/organização & administração , Humanos , Relações Interprofissionais , Qualidade da Assistência à Saúde/organização & administração
2.
Toxicol Lett ; 162(2-3): 181-5, 2006 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-16406420

RESUMO

The people studied were male volunteers without occupational and dietary exposure to PAH: 27 smokers (10 cigarettes or more) and 27 non-smokers matched for age and socio-professional category. For each person, all the 24h voided urine samples were reassembled in a single sample. 1-Hydroxypyrene (1-OHPy) and 3-hydroxybenzo[a]pyrene (3-OHBaP) were then determined by automated column-switching high-performance liquid chromatography. Urinary 1-OHPy ranged from 0.041 to 0.530 micromol/molCreatinine (arithmetic mean 0.144, median 0.115) for smokers and from 0.01 to 0.148 mmol/molCreatinine (arithmetic mean 0.044, median 0.032) for non-smokers. These values are close to those of some other studies. Urinary 3-OHBaP ranged from <0.01 to 0.084 nmol/molCreatinine (arithmetic mean 0.030, median 0.023) for smokers and from <0.01 to 0.045 nmol/molCreatinine (arithmetic mean 0.014, median 0.011) for non-smokers. Considering more particularly the urinary 3-OHBaP values, the influence of smoking could be important among workers exposed to low levels of BaP (<100 ng/m(3)) and the concentrations for smokers were equivalent to most of the preshift values of exposed workers. The dietary BaP intake was slightly lower than the BaP intake for an average smoker. From the present study, temporary basic reference levels may be proposed for urinary 3-OHBaP.


Assuntos
Benzopirenos/metabolismo , Fumar/urina , Adulto , Biomarcadores/urina , Monitoramento Ambiental , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Pirenos/metabolismo
3.
Int J Med Inform ; 74(5): 367-76, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15893259

RESUMO

OBJECTIVES: To evaluate a semi-automatic data extraction from the electronic medical record (EMR) of general practitioners (GPs) through a comparison with a paper sheets data collection simultaneously used in a primary care research project on the quality of prescribing for osteoarthritis in the elderly. SUBJECTS: One hundred and fifty-two GPs using five different EMR-software systems participated with the semi-automatic data extraction from the EMR and 233 GPs collected data with paper registration sheets. METHODS: The proportion of patients with respectively a drug prescription, paracetamol, a non-steroidal anti-inflammatory drug (NSAID) and ibuprofen were compared between the semi-automatic extraction and the paper data collection and among the EMR-software systems. RESULTS: Using the semi-automatic data extraction, a significantly lower proportion of patients on drugs was obtained compared to the paper data collection (adjusted OR: 0.31; 95% CI 0.25-0.39). However, the proportion of patients on a specific type of drug was comparable. Within the results from the semi-automatic extraction, the results were heterogeneous among the different EMR-software systems. CONCLUSIONS: The semi-automatic data extraction with multiple EMR-software systems proposed in this study seems suitable for quality of prescribing assessment in primary care. However, it may be less reliable when only a single EMR-software is used.


Assuntos
Prescrições de Medicamentos , Sistemas Computadorizados de Registros Médicos , Médicos de Família , Padrões de Prática Médica , Qualidade da Assistência à Saúde , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/uso terapêutico , Bélgica , Coleta de Dados/métodos , Feminino , Humanos , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Osteoartrite/tratamento farmacológico
4.
Int Arch Occup Environ Health ; 77(3): 177-85, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-14760537

RESUMO

OBJECTIVES: To compare the apparent urinary excretion rates of both creatinine and 1-hydroxypyrene (1-OHP) and to assess the value of creatinine normalization for both toxicokinetic analysis and the routine examination of workers. METHODS: All urine samples were collected from individuals who had been exposed to polycyclic aromatic hydrocarbons (PAHs), occupationally and non-occupationally, for at least 24 consecutive hours. Urinary creatinine and 1-OHP were determined. 1-OHP excretion rates were expressed either as a function of creatinine excretion rate or as unadjusted values. Theoretical relationships between creatinine-normalized excretion of metabolites and body weight-adjusted inhaled dose were drawn for men with a constant body mass index. RESULTS: Creatinine excretion rate paralleled 1-OHP excretion rate. The plot of creatinine excretion rate-adjusted excretion rate of 1-OHP vs time led to smooth curves for determination of toxicokinetic parameters. Creatinine normalization was adequate, even for samples with a urinary creatinine concentration below 0.5 g/l or above 3 g/l. A theoretical analysis revealed that men weighing between 50 kg and 100 kg, exposed to a constant dose of a pollutant producing a urinary metabolite excreted by the same mechanism as creatinine, would exhibit a body weight-adjusted dose span of 2 with an accompanying creatinine-normalized metabolite excretion span of 2.23-fold. CONCLUSION: The kinetics of creatinine excretion parallels that of 1-OHP, and a creatinine excretion rate-normalized excretion rate of 1-OHP appears to allow for a better determination of the toxicokinetic parameters of 1-OHP urinary excretion. At least in the case of 1-OHP, creatinine normalization seems valid, even for very dilute or very concentrated urine samples. Finally, because creatinine normalization not only compensates for variable diuresis but also correlates better with the body weight-adjusted dose of the parent compound, it should be used in biological monitoring of exposure to (PAHs) pyrene and to other substances whose urinary biomarker excretion kinetics parallel that of creatinine.


Assuntos
Creatinina/urina , Exposição Ocupacional , Compostos Policíclicos/toxicidade , Pirenos/análise , Humanos , Masculino , Compostos Policíclicos/farmacocinética
5.
Ann Occup Hyg ; 46(7): 617-28, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12270886

RESUMO

Bitumen fumes emitted during road paving and roofing contain polycyclic aromatic compounds (PACs) of potential health concern. Little information is available for an experimental device devoted to inhalation experiments with animals exposed to bitumen fumes, and in all studies the systems were never validated for a range of fume concentrations, which prohibited their use for toxicological concentration-effect studies. Therefore, the purpose of this study was to validate a new experimental device able to generate bitumen fumes at different total particulate matter (TPM) concentrations with a linear correlation between TPM and the concentrations of different PACs, thus allowing toxicological dose-response studies with fumes representative of those in the field. Atmosphere samples collected from an animal exposure chamber allowed the determination of TPM, toluene soluble matter, polycyclic aromatic hydrocarbons (PAHs) and semi-volatiles. The particulate size distributions were determined in order to assess the deposition pattern in the respiratory tract. The temperature of 170 degrees C was chosen by analogy with the upper range of the temperature used during paving operations. The temperature of the air passing over the fume emission area was regulated to 20 degrees C and stirring of the heated bitumen was restricted to 90 r.p.m. The data show that the objective of developing a static fume generation system that reproducibly produces fumes in the inhalation chamber for specified target concentrations (TPM) were successful. The within-day variation coefficients for TPM were between 2.5 and 6.1%. The day-to-day variations for TPM concentration were between 4.1 and 5.8%. The concentrations of the 4-5 ring PAHs and the polycyclic aromatic sulphur heterocycles were proportional to the TPM concentration. The 2 and 3 ring PAH concentrations showed a deviation from proportionality with the TPM, probably due to their re-evaporation during sampling. The mass median aerodynamic diameter of airborne particles varied from 1.4 micro m at a fume concentration of 5 mg/m(3) to 3.2 micro m at 100 mg/m(3). In conclusion, this equipment was suitable for nose-only inhalation studies in the 5-100 mg/m(3) range of TPM. Bitumen fumes were generated with a good reproducibility under well-controlled conditions. Finally, the PAH profiles from atmospheric samples were in good agreement with those measured during road paving.


Assuntos
Hidrocarbonetos , Hidrocarbonetos Policíclicos Aromáticos , Hidrocarbonetos Policíclicos Aromáticos/análise
6.
Appl Occup Environ Hyg ; 17(7): 495-500, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12083170

RESUMO

A UV spectrophotometric procedure was validated for the determination of organic soluble matter in bitumen fumes collected by filtration technique. Ultrasonic extraction was carried out with toluene, an efficient extraction solvent for polycyclic aromatic hydrocarbons, followed by UV absorbance measurements at 320 nm. A calibration curve is plotted from the same set of samples determined by classical weighing method. Further determinations can also be made using the slope factor of the calibration curve. The procedure presents obvious simplicity and rapidity advantages and is less prone to losses than the measurements of weight. Inter-method comparisons of samples collected from experimental laboratory-generated penetration bitumen fumes commonly used in road paving showed that the three available procedures-weighing, infrared, and UV--described for the determination of organic soluble matter yield equivalent results.


Assuntos
Monitoramento Ambiental/métodos , Hidrocarbonetos/análise , Exposição Ocupacional/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Espectrofotometria/métodos , Exposição por Inalação , Concentração Máxima Permitida , Exposição Ocupacional/efeitos adversos , Saúde Ocupacional , Hidrocarbonetos Policíclicos Aromáticos/química , Sensibilidade e Especificidade
7.
Stud Health Technol Inform ; 93: 163-9, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-15068004

RESUMO

The paper describes the experiences with a Belgian Primary Care data Network from 1999 till 2002. Three cycles of data collection have been performed. The network involves about 300 general practitioners (GPs) and up to 8 different software packages. This network is semi-anonymous, semi-automatic and mixed (paper and electronic with various software's). For the coming next years, efforts should be focused on solving some frequently occurring problems with the data collection through the EPR, such as a considerable number of data lacking and the fact that GPs do not always use the problem oriented structure of the EPR (Electronic Patient Record). Afterwards, more promising usage could be considered and developed such as repeated data collection using a same GPs' sample, long-term recording studies, usage of larger GPs' samples, etc.


Assuntos
Redes de Comunicação de Computadores , Coleta de Dados/métodos , Sistemas Computadorizados de Registros Médicos , Atenção Primária à Saúde , Bélgica , Redes de Comunicação de Computadores/organização & administração , Redes de Comunicação de Computadores/estatística & dados numéricos , Armazenamento e Recuperação da Informação/métodos , Sistemas Computadorizados de Registros Médicos/organização & administração , Sistemas Computadorizados de Registros Médicos/estatística & dados numéricos , Médicos de Família , Atenção Primária à Saúde/organização & administração , Atenção Primária à Saúde/estatística & dados numéricos
8.
Sci Total Environ ; 300(1-3): 37-49, 2002 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-12685469

RESUMO

Bitumens fumes contain polycyclic aromatic compounds (PAC). There is a possibility of long-term health effects following chronic exposure by inhalation or skin contamination in asphalt road pavers and highway maintenance workers. Epidemiological and experimental studies on this topic are reviewed and the possible causes of cancer discussed with a primary focus on heterocyclic polyaromatic compounds. In 2001, the results of the IARC epidemiological study confirmed an excess of lung cancer despite a lower cancer mortality. In vitro genotoxicity and mechanistic studies demonstrated a mutagenic effect of bitumen fume condensates (BFC) and some data suggested that the polycyclic aromatic hydrocarbons (PAH) analysed were not the major genotoxic compounds in bitumen fume condensates. Other compounds such as nitrogen-, sulfur- and/or oxygen-containing PAH or their alkyl substituted analogues, mutagenic in the Ames mutation assay, may be involved in the genotoxic effect of BFC. After skin painting with BFC, DNA adducts were found in skin, lung and lymphocytes of all the treated animals. Differences in the adduct patterns were also observed, but a more polar adduct was common to the three tissues and not observed in those from rats treated with coal-tar fume condensates (CTFC). Rat inhalation experiments with bitumen fumes confirmed the presence of a DNA-adduct in the lungs with the same Rf as the previous polar adduct. This adduct therefore merits further investigation as a potential biomarker in lymphocyte DNA to follow exposed workers. All the analytical data and the mechanistic data are complementary and suggest the potential role of thiophenes in the genotoxicity of bitumen fumes. Some thiophenes have lower mutagenic activity than their isosteric PAH, whereas others are very potent carcinogens. Generally, the sulfur analogues of PAH (SPAH) in bitumen fumes have a higher concentration than the PAH of similar molecular weight, whereas the SPAH in coal-tar fumes have a much lower concentration than the corresponding PAH. This may explain why the more polar adducts have been detected only in animals exposed to bitumen fume. In a skin carcinogenicity study of condensed asphalt roofing fumes, it has been demonstrated that the most active fractions were those containing a variety of aromatic SPAH. In conclusion to this review, there is an interest in determining the chemical identity of the major DNA adducts induced by BFC. This would allow experimental studies on the carcinogenic potency of these compounds and their validation as potential biomarkers. These compounds could thus merit further analytical investigation in preference to the PAH included in the list of the US Environmental Protection Agency that are currently being analysed by the industry in field studies.


Assuntos
Adutos de DNA , Hidrocarbonetos/efeitos adversos , Exposição por Inalação , Exposição Ocupacional , Administração Cutânea , Animais , Biomarcadores/análise , Testes de Carcinogenicidade , Dano ao DNA , Humanos , Peso Molecular , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Medição de Risco , Meios de Transporte
9.
Curr Med Chem ; 8(7): 815-28, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11375752

RESUMO

Oxidative stress in brain is emerging as a potential causal factor in aging and age-related neurodegenerative disorders. Brain tissue from living patients is difficult to acquire; hence, animal models of aging and age-related neurodegenerative disorders, though not perfect models, have provided tissue to study the role of oxidative stress in these disorders. In this review, the central role of oxidative damage in brain in models of accelerated aging (progeria and Werner's syndrome) and the age-related neurodegenerative disorders, Alzheimer's disease and Huntington's disease, will be presented and evaluated. To the extent that the animal models faithfully mirror their respective disorders, and based on the totality of the studies, it is apparent that oxidative stress, the excess of free radicals over the means of scavenging these harmful agents, may play critical roles in the molecular basis of accelerated aging, Alzheimer's disease, and Huntington's disease.


Assuntos
Senilidade Prematura/fisiopatologia , Doença de Alzheimer/fisiopatologia , Encéfalo/metabolismo , Doença de Huntington/fisiopatologia , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Senilidade Prematura/etiologia , Doença de Alzheimer/etiologia , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/metabolismo , Modelos Animais de Doenças , Doença de Huntington/etiologia , Camundongos , Doenças Neurodegenerativas/etiologia , Doenças Neurodegenerativas/fisiopatologia , Ratos
10.
Am J Emerg Med ; 18(7): 820-4, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11103737

RESUMO

High-pressure injection injury hides the true extent of the lesions behind an apparent small and harmless puncture of the finger or the hand. Through clinical description, we wish to point out the need for prompt treatment to avoid mutilating and function-threatening complications. We wish to outline the role of the emergency physician who must be aware of the incidence of high-pressure injection injury and become accustomed to early referral to a surgeon, experienced in extensive surgical exploration, removal of foreign bodies, and rehabilitation. The open-wound technique gives the best results. We also point out that failure to refer may become an increasing focus of negligence claims.


Assuntos
Acidentes de Trabalho , Traumatismos da Mão/patologia , Ferimentos Penetrantes , Adulto , Serviço Hospitalar de Emergência , Corpos Estranhos , Traumatismos da Mão/complicações , Traumatismos da Mão/cirurgia , Humanos , Masculino , Pressão
11.
J Chromatogr B Biomed Sci Appl ; 748(2): 337-48, 2000 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-11087076

RESUMO

3-Hydroxybenzo[a]pyrene (3-OHB[a]P), one of the metabolites of benzo[a]pyrene (B[a]P), has been determined in human urine using an automated column-switching procedure. The hydrolysed biological sample is centrifuged just prior to being injected into a reusable precolumn loop, which is packed with a preparative phase and coupled on-line to a liquid chromatographic (LC) system. A rapid pre-treatment of the hydrolysed sample, consisting of a concentration and a crude clean-up, is performed on the precolumn. The analytes are then non-selectively desorbed with the LC eluent and the sample is cleaned again in three successive purification columns using the direct transfer or "heart-cut" technique. The pre-treatment does not exceed 3 min. and the entire analytical purification and separation procedure takes less than 30 min. Average 3-OHB[a]P recovery reaches 95% in the 1-50 ng/l range of urine, and the detection limit is 0.1 ng/l urine for a 3 ml injection of hydrolysed urine. The developed method was compared with a more time-consuming off-line method to analyse urines of B[a]P gavaged rats; the statistical treatment indicates that both methods are in agreement. The method was applied to purify and concentrate the urine samples of workers exposed and apparently unexposed to polycyclic aromatic hydrocarbons (PAHs).


Assuntos
Benzopirenos/análise , Cromatografia Líquida de Alta Pressão/métodos , Animais , Automação , Cromatografia Líquida de Alta Pressão/instrumentação , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Urina
12.
Ann Occup Hyg ; 44(2): 89-100, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10717260

RESUMO

Five representative workers and two external observers were monitored by personal air and urinary 1-hydroxypyrene (PyOH) sampling for a four-shift working week in an artificial shooting target factory. The targets (clay pigeons), are made from petroleum pitch and molded at 190 degrees C. No respiratory protective mask was worn. Atmospheric concentrations of pyrene and benzo (a) pyrene (BaP) ranged from 0.66 to 5.05 microg/m(3) and 0.037 to 0.270 microg/m(3) respectively with a mean pyrene/BaP ratio of about 20 and a correlation r = 0.51. Maximum PyOH urinary excretion ranged from 1.84 to 10.9 micromol/molCreat. This occurred at the postshift for the observers but often appeared later for workers: up to 10.75 h for the person with the apparently highest dermal exposure. The apparent PyOH excretion half lives ranged from 1.9 to 12.5 h with an arithmetic mean of 6.1 h. All these data were confirmed by additional measurements taken over a weekend after the postshift. The correlation between atmospheric pyrene and urinary PyOH concentrations (increase over the shift) was poor (r = 0.37). It improve greatly (r = 0.74) if the amount of pyrene inhaled over the shift and the corresponding amount of PyOH excreted were considered. The ratio of urinary excreted PyOH to the pyrene inhaled dose (with assumed retention of 100%), ranged from 0.18 to 0.70 (arithmetic mean = 0.34). This suggests that the respiratory tract is the main entrance route for pyrene (apart from the worker who handled crude targets without gloves).


Assuntos
Poluentes Ocupacionais do Ar/urina , Mutagênicos/análise , Exposição Ocupacional , Hidrocarbonetos Policíclicos Aromáticos/urina , Pirenos/análise , Poluentes Ocupacionais do Ar/análise , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental/instrumentação , Feminino , Humanos , Indústrias , Masculino , Hidrocarbonetos Policíclicos Aromáticos/análise , Ultrassom
13.
Ann Occup Hyg ; 44(1): 15-29, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10689756

RESUMO

Bitumen fumes emitted during road paving or roofing contain polycyclic aromatic hydrocarbons (PAHs). Experimental studies have been previously performed to test the carcinogenic potency of bitumen fumes. Some of them have been criticised either on the grounds that the fume condensates were not representative of fumes to which humans are exposed or because the fumes were never characterised in terms of particle size and poorly in terms of composition and concentration in the chambers. For a nose-only inhalation study, we have evaluated the ability of a new fume generation system to deliver stable and reproducible atmospheres of bitumen fumes to an inhalation chamber and investigated the representativity of the fumes generated at a concentration level of 5 mg/m3. The fume generator comprises: (1) an insulated 20 l heated kettle (200 degrees C for bitumen); (2) an insulated inlet pipe with a needle valve to adjust the flow of the test compound from the kettle; (3) a fume generation chamber equipped with a series of interchangeable channels of different width. The fume concentration in the exposure chamber can be controlled by changing the channel width or by restricting the evaporation surface with aluminium foil, and/or by changing the flow rate. Samples of the atmosphere in the chamber were collected and analysed for quantitative determination of total particulate matter (TPM), soluble matter, benzo[a]pyrene (B[a]P) content of the fumes and other PAHs, and evaluation of the particle size distribution. The representativeness of the fumes has been tested by comparison with fumes generated in the Shell small-scale fume rig, which was previously validated against field fumes collected during paving operations. Evaporative losses from the filters during sampling, transport and storage have been also assessed. At 5 mg/m3 TPM, the agreement between laboratories was quite good for the TPM analyses and was good for the soluble matter and B[a]P. Evaporative losses may lead to underestimation of the true exposure level in the inhalation chambers but the use of an XAD-2 cartridge backup is one approach to partially recover losses which occur on the filter. The particle size distributions are somewhat different from those reported for fumes associated with roofing and indoor mastic laying works, in that we found more than 85% of particles to be smaller than 1 micron, compared with 40% particles in the previous analyses. In conclusion, this equipment allows reproducible generation of fumes at the 5 mg/m3 TPM that are fairly representative of those produced in the field with the same bitumen.


Assuntos
Hidrocarbonetos/análise , Exposição Ocupacional/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Desenho de Equipamento , Humanos , Hidrocarbonetos/química , Exposição por Inalação , Reprodutibilidade dos Testes
14.
Ann Occup Hyg ; 44(1): 31-41, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10689757

RESUMO

During the hot application of bitumen-containing materials, e.g. in road paving or roofing, fumes are emitted that contain traces of polycyclic aromatic compounds (PACs). Although worker's exposure to these fumes is low, it might lead to health problems. For studying DNA adduct formation as a consequence of inhalation of bitumen fumes we developed and validated an inhalation system (a dynamic fume generator plus a nose only inhalation chamber). This paper presents and discusses the analytical results from the different laboratories involved in this study on the fumes sampled in the inhalation chamber during three series of experiments where the animals were exposed to fumes at the 5 mg/m3 and 50 mg/m3 level, coming from bitumen heated at 200 degrees C and, as a positive control, fumes from coal tar, heated to 110 degrees C at the 5 mg/m3 level. The following parameters were controlled: temperatures at different key places in the generator; humidity of the chamber; the bitumen or coal tar flow rate; and Total Particulate Matter (TPM). Analyses were performed for Benzene Soluble Matter (BSM), the EPA polycyclic aromatic hydrocarbon (PAH) mixture and for a number of heteroatom-containing PACs. The data show that the coal tar fumes produced at 110 degrees C were very volatile and that most of the differences in particulate matter found between the laboratories can be attributed to evaporative losses. The bitumen fumes boil 25-50 degrees C higher and contain higher boiling compounds. A comparison is made between the PAC exposure profiles for bitumen experiments aimed at 5 and 50 mg/m3. Although the same molecules are found in both fumes their proportion is dramatically different. This effect is largest with the 2- and 3-ring PACs, the ratio of the concentrations found in the 50 mg/m3 TPM concentration to that in the 5 mg/m3 experiment gradually declines from 5500 for acenaphthene to 500 for pyrene, for the 5-ring PACs this ratio is 20-30. As function of their vapour pressure, the ratios of the concentrations of the hetero PACs follow the same trend as that of the 16 EPA PAHs and are of the same order of magnitude. In conclusion, for the compounds investigated, the equipment delivers a fume atmosphere in a reproducible manner. The 50 mg/m3 bitumen fumes are not representatives of field fumes. The reason for these quantitative differences is unclear and further work would be needed to clarify this. Nevertheless it was felt that these fumes at 50 mg/m3 might be a useful tool for qualitative detection of DNA adducts in an animal exposure study.


Assuntos
Hidrocarbonetos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Animais , Adutos de DNA , Relação Dose-Resposta a Droga , Desenho de Equipamento , Humanos , Hidrocarbonetos/efeitos adversos , Exposição por Inalação , Exposição Ocupacional , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos
15.
J Chromatogr B Biomed Sci Appl ; 712(1-2): 95-104, 1998 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-9698232

RESUMO

An extractionless method for determining aflatoxin M1 (AFM1), a major metabolite of aflatoxin B1 (AFB1), in human urine was developed. The biological fluid is injected directly into the chromatographic system after simple dilution and centrifugation. A pre-column, packed with a cation-exchange phase and coupled on-line to a column-switching liquid chromatography (LC) system, is used for sample pre-treatment and concentration. The analytes are non-selectively desorbed with the LC eluent and cleaned by means of a column-switching procedure. Pre-treatment and analysis were performed within 40 min. Average AFMI recovery reached 97% in the 10-100 ng/l range of urine. The detection limit of AFM1 in urine and milk was 2.5 ng/l for 1 ml of injected sample. A comparison with an immunoaffinity column clean-up and LC method was performed. The method was applied to determine AFM1 in the urine of AFB1 gavaged rats, and in the urine of both potentially exposed and supposedly unexposed workers. The method was also extended to milk.


Assuntos
Aflatoxina M1/urina , Aflatoxina M1/análise , Animais , Cromatografia Líquida de Alta Pressão , Humanos , Masculino , Leite/química , Ratos , Ratos Sprague-Dawley
16.
J Cataract Refract Surg ; 24(8): 1070-8, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9719966

RESUMO

PURPOSE: To determine the efficacy of 3 current methods used to remove corneal epithelium prior to photorefractive correction of hyperopia and to compare clinical data in patients who had rotary brush or blunt scrape epithelial removal in the treatment of hyperopic photorefractive keratectomy (PRK). SETTING: University of Ottawa Eye Institute, Ottawa General Hospital, Ottawa, Ontario, Canada. METHODS: The epithelium from human eye-bank eyes was removed using a Paton spatula, 15% alcohol, and the Amoils rotating plastic brush. The effects were examined by scanning and transmission electron microscopy. Twelve month postoperative data were obtained on 25 eyes with refractions of +1.00 to +4.00 diopters (D) that had been treated for hyperopia with the VISX Star excimer laser, using blunt scrape or the rotary brush to remove the corneal epithelium. RESULTS: All 3 methods effectively removed corneal epithelium. The Paton spatula, however, left small nicks in Bowman's layer. Both the rotating brush and alcohol debridement left Bowman's layer intact. Alcohol treatment required follow-up epithelial debris removal, while brushing left minimal amounts of debris. There was a strong trend toward rapid epithelial healing in the brushed corneas compared with the scraped ones, but this was not statistically significant. Clinically, at 12 months postoperatively, brushed corneas showed a trend toward more superior outcomes than scraped corneas in actual refractive outcome, uncorrected visual acuity (UCVA), lines of UCVA gained, and predictability of the desired outcomes. However, only the outcome in UCVA of 20/40 or better and the decreased incidence of haze in the brushed corneas over scraped ones were statistically significant. CONCLUSIONS: Both alcohol and the rotating brush provide a quick, effective means of removing the corneal epithelium with minimal risk of damage to Bowman's layer. In our experience, the brush technique was as effective as and possibly superior to the blunt scrape for epithelial removal in hyperopic PRK.


Assuntos
Desbridamento/métodos , Epitélio Corneano/cirurgia , Hiperopia/cirurgia , Procedimentos Cirúrgicos Oftalmológicos , Ceratectomia Fotorrefrativa , Adulto , Epitélio Corneano/ultraestrutura , Feminino , Humanos , Hiperopia/patologia , Lasers de Excimer , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Oftalmológicos/instrumentação , Refração Ocular , Segurança , Resultado do Tratamento , Acuidade Visual , Cicatrização
17.
Virology ; 241(2): 285-97, 1998 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9499803

RESUMO

We previously demonstrated that infection of primary human thymic dendritic cells (DCs) with laboratory strains of HIV leads to the release of soluble factor(s) which induced thymocyte killing. In the present paper, we extend the characterization of this process. Our results reveal that primary HIV-1 isolates are similarly able to induce the production of cytotoxic factor(s) from thymic DCs and that the release of such factor(s) is dependent on viral infection. Interestingly, we observed that CD4+ and CD8+ purified thymocyte subsets, and activated PBMCs are susceptible to the cytotoxic activity, whereas freshly isolated resting PBMCs are resistant to this effect. Cycloheximide treatment prevents the killing of thymocytes exposed to HIV-infected DC supernatant, revealing that this form of cell death is an active biological process requiring protein synthesis. Finally, our data suggest that FasL and TNF alpha could both participate in the killing process. These in vitro observations provide a plausible model, whereby HIV-infected DCs can play a role in vivo in the induction of uninfected thymocyte killing.


Assuntos
Citotoxicidade Imunológica , Células Dendríticas/imunologia , Células Dendríticas/virologia , HIV-1/imunologia , Proteínas/imunologia , Timo/imunologia , Animais , Apoptose , Ciclo Celular , Células Cultivadas , Criança , Pré-Escolar , Meios de Cultivo Condicionados , Cicloeximida/farmacologia , Fragmentação do DNA , Células Dendríticas/metabolismo , HIV-1/fisiologia , Antígenos HLA-DR/imunologia , Humanos , Lactente , Recém-Nascido , Fatores Matadores de Levedura , Camundongos , Biossíntese de Proteínas , Inibidores da Síntese de Proteínas/farmacologia , Proteínas/metabolismo , Timo/citologia , Fator de Necrose Tumoral alfa/imunologia , Vírion , Receptor fas/imunologia
18.
Microsc Res Tech ; 38(3): 267-75, 1997 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9264338

RESUMO

ABSTRACT Human thymic dendritic cells (DC) represent a member of the bone marrow-derived dendritic cell family. They have a dendritic shape and are found in small numbers mainly at the corticomedullary border and in medullary regions of the thymus. Human thymic DC were isolated by density gradient separation, followed by treatment with CD2, CD7, CD1, and CD11b mAb and immunobeads magnetic separation. The resulting population contains 60-75% brightly HLA-DR+ cells which present the morphological characteristics of DC observed in situ. Extensive phenotypic analysis confirmed that they are of mesenchymal origin and that some express CD11a and CD54 molecules. Freshly isolated DC do not stain with a wide variety of anti-T-B and -monocyte or -macrophage mAb. However, they acquire the CD1 molecule after a few days in culture. By using a cell sorter we obtained 90-95% of purified human thymic DC. Functional studies have shown that human thymic DC are potent activators in mixed lymphocyte reactions, act as accessory cells in mitogenic thymocyte proliferation, increase the thymocyte proliferative response to a toxin signal, and produce IL-1. They also formed spontaneous physical associations with thymocytes, which raises questions about the implication of DC in differentiation and/or maturation processes of thymocytes.


Assuntos
Células Dendríticas/ultraestrutura , Timo/ultraestrutura , Células Dendríticas/fisiologia , Humanos , Timo/citologia
20.
Acta Orthop Belg ; 63(3): 215-7, 1997 Sep.
Artigo em Francês | MEDLINE | ID: mdl-9441559

RESUMO

Pseudoaneurysm of the inferomedial genicular artery is a rare complication of arthroscopy. We report one case after arthroscopy ans medialisation of the anterior tibial tuberosity. Exploration and excision were performed.


Assuntos
Falso Aneurisma/etiologia , Artroscopia/efeitos adversos , Endoscopia/efeitos adversos , Articulação do Joelho/irrigação sanguínea , Idoso , Falso Aneurisma/diagnóstico por imagem , Falso Aneurisma/cirurgia , Angiografia , Artérias/cirurgia , Feminino , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Tíbia/cirurgia
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