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Biomedical subjects

W Szymczak

Publications and source records attributed to W Szymczak.

At least 19 recordsLinked to original sources
PubMed2004

Patients with Paget disease of nipple and with palpable mass in breast have unfavorable prognosis.

Recent data indicate that in breast cancer patients the presence of Paget disease of the nipple may be related to poor prognosis. Therefore, we decided to assess long-term results of the treatment of such patients, and to assess the relationship between the physical and pathological findings and prognosis. The files of 60 patients with Paget disease of the nipple who were treated between 1977 and 2000 were analyzed retrospectively with respect to the results of physical and pathologic examinations, disease recurrence and survival. In 38/60 patients, the cancer was invasive. In 26/60 patients, palpable masses in the breast were diagnosed. The 5-year overall survival probability was 0.68; the probability was 0.82 for patients without palpable masses, 0.51 for those with palpable masses, 0.91 for patients without invasive cancer and 0.58 for patients with associated invasive cancer. In conclusions, patients with Paget disease of the nipple and with palpable mass in the breast had unfavorable diagnosis. The nature of all nipple changes should be explained as early as possible in order to diagnose the disease when no mass is palpable in the breast.

Adult↗
PubMed2003

Immunohistochemical evaluation of P21ras and P53 proteins expression in human non-small-cell lung cancers.

Human non-small-cell lung cancers (NSCLCs) of 48 patients were analyzed immunohistochemically to detect P21 ras and P53 proteins expression. The relationship between P21 ras and P53 proteins expression and clinicopathologic findings was also assessed. DAKO EnVision TM detection system was employed in the study. The P21 ras and P53 proteins expression was shown in 75% (36/48) and 33.3% (16/48) studied NSCLCs, respectively. In both cases the difference was significant when compared with adequate negative control. Simultaneous expression of both studied proteins was observed in all cases in which P53 expression was noticed. No significant association of P21 ras and P53 expression was found with age, histologic type, histologic grade, tumor size or lymph node metastasis of the studied NSCLCs. Therefore, our study suggests that P21 ras and P53 protein play a role in the pathogenesis of NSCLCs but they have no value as a prognostic markers in the case of lung cancers.

Adenocarcinoma↗
PubMed2003

Glutathione S-transferase M1 and P1 metabolic polymorphism and lung cancer predisposition.

Individual susceptibility to different environmental agents is expected to be associated with alterations in metabolism of xenobiotics. Thus, genetic polymorphism of glutathione S-transferase (GST) can be recognized as a potential risk modifier in lung cancer development. The distribution of GSTM1 and GSTP1 genotypes was studied in a group of 138 diagnosed lung cancer patients and in 165 controls living in central Poland and RFLP-PCR technique was applied. The frequency of GSTM1 null genotype and GSTP1 Val single and duplicated alleles was similar among patients and controls. GSTM1 homozygous deletion was most prevalent in small-cell carcinoma groups (adjusted odds ratio (OR): 2.32, 95% confidence interval (CI): 0.98-5.52). In patients and controls, GSTM1A genotype was most frequent (34.1% vs. 37.0%). The estimated lung cancer risk for GSTM1 null, GSTP1 Ile/Val and GSTP1 Val/Val combined genotype was 1.44 (95% CI: 0.73-2.83), suggesting the absence of modifying effect of defective GSTM1 and GSTP1 alleles on lung cancer predisposition.

Adenocarcinoma↗
PubMed2001

Nested case-control study of lung cancer among pulp and paper workers in relation to exposure to dusts.

BACKGROUND: Numerous studies have indicated an increased risk of lung cancer in pulp and paper industry workers. In a 1990 survey, standardized mortality ratio (SMR) was found to be 122 (95% CI:96-153) for lung cancer in Polish male workers in the pulp and paper industry, and 166 (95% CI:95-270) among workers engaged in paper production. METHODS: A nested case-control design within a cohort of pulp and paper workers was applied. Seventy-nine lung cancer cases and 237 "healthy" controls were selected from the cohort of 10,460 workers employed during the years 1968-1990, and observed until the end of 1995. Based on personnel files, occupational exposure was reconstructed by experts. Using a questionnaire, data on smoking habits were collected. ORs unadjusted and adjusted for smoking were calculated applying the model of conditional logistic regression. RESULTS: Occupational exposure to inorganic dusts (kaolin, lime, cement, brick, grindstone) adjusted for smoking was a significant lung cancer risk factor, with a 4.0-fold risk (95% CI:1.3-12.6), and a dose-response by cumulative dose index. Among organic dusts only wood dust increased albeit insignificantly the risk for those exposed (adjusted for smoking OR = 2.1, 95% CI:0.9-4.9), but without dose-response relationship. CONCLUSIONS: Exposure to occupational dust with relatively low content of silica, but at high concentrations may be considered as a factor increasing lung cancer risk. However, the observation made in this study should be viewed with caution as it was based on a small number of cases, and further evidence is needed to confirm or refute the authors' hypothesis.

Air Pollutants, Occupational↗
PubMed2001

Cardiovascular disturbances in workers exposed to carbon disulfide.

According to literature data myocardial infarction was often the first noticeable effect of CS2 on the cardiovascular system. Therefore, a question arises whether earlier circulatory lesions are absent in CS2-exposed people, or they are present but are not detectable by the diagnostic methods used. The aim of our study has been to determine whether electrocardiological disturbances do occur in exposed people, and their association, if any, with the level of CS2 exposure. Modern diagnostic methods (resting and 24-h ECG, heart rate variability, late ventricular potential analysis, and long-term blood pressure monitoring) were used to answer this question. The examination comprised 177 male workers aged 24-66 years (44+/-12), employed under conditions of the exposure for 5-38 years (14+/-9), and 93 male workers non-exposed to CS2 aged 23-65 years (41+/-12). Results of our studies show that abnormalities in resting and/or 24-h ECG recordings occur significantly more frequently in people exposed to CS2 than in the controls. ECG abnormalities were found primarily among the workers with a long, over 20-year, period of exposure. The considerable coincidence between the questionnaire and ECG results was found (87% reported complaints were confirmed by ECG data). Therefore it seems that all CS2-exposed people reporting heart symptoms should be subjected to a detailed examination. The frequency of late ventricular potentials in CS2-exposed people was not higher than in the controls. It may indicate that the ECG disturbances observed in those people were associated with functional rather than organic changes. Results of long-term ABP monitoring did not show increased incidence of elevated blood pressure in the exposed group. As the levels of the risk factors of ischemic heart disease in the exposed and control groups were similar, it seems that exposure to CS2 was responsible for the significant changes in the circulatory system.

Adult↗
PubMed2001

Hearing loss among workers exposed to moderate concentrations of solvents.

OBJECTIVES: It is known that some industrial organic solvents are ototoxic. This study was aimed at evaluating the hearing effects of a mixture of organic solvents alone or in combination with noise on employees in paint and lacquer enterprises. The concentration of solvents was below the occupational exposure limits (OEL) for most of the subjects. METHODS: Altogether 517 subjects were divided into the following three groups: persons with no risk due to noise or organic solvent exposure at the workplace, workers exposed to organic solvents only, and workers exposed to both organic solvents and noise. RESULTS: The relative risk (RR) of hearing loss in the solvent-only exposure group was significantly increased (RR 4.4 and RR 2.8 for noise exposure of < 80 dB-A and < 85 dB-A, respectively) in a wide range of frequencies (2-8 kHz). No additional risk in the solvent + noise exposure group was found (RR 2.8). Hearing thresholds were significantly poorer in a wide range of frequencies (1-8 kHz) for both groups exposed to solvents, when compared with the reference group. The mean hearing thresholds at frequencies of 2-4 kHz were poorer for workers exposed to solvents + noise than for the solvent-only group; this finding suggests an additional effect for noise. However, there was no correlation between hearing loss and the extent of solvent exposure. CONCLUSIONS: The results indicate that occupational organic solvent exposure at moderate concentrations increases the risk of hearing loss, and the ototoxic effects should be considered when the health effects of exposed workers are monitored.

Adult↗
PubMed2000

Time-of-flight secondary ion mass spectrometry of matrix-diluted oligo- and polypeptides bombarded with slow and fast projectiles: positive and negative matrix and analyte ion yields, background signals, and sample aging.

Human angiotensin II, chain B of bovine insulin, and porcine insulin were determined by time-of-flight secondary ion mass spectrometry under impact of approximately 25 keV Xe+ and SF5+ ion beams and approximately 100 MeV 252Cf fission fragments. Matrix-embedded samples, dissolved in a large surplus of alpha-cyano-4-hydroxycinnamic acid, were prepared by nebulizer spray deposition, neat samples by the droplet technique. It is shown that the status of the sample can be assessed by evaluating the matrix-specific features of the mass spectra. The beneficial effect of matrix isolation was small for angiotensin but large for the insulin samples, which did not show parent peaks from neat material. Negative ion yields under SF5+ impact were up to a factor of 50 higher than with Xe+. For positive secondary ions, the enhancement was much smaller. The mass spectra produced by slow ion beams or fast fission fragments were qualitatively similar. Quantitative differences include the following: with fast projectiles the yields were about 10-30 times higher than with slow ions, but similar for negative ion emission under SF5+ bombardment; the analyte-to-matrix yield ratios were higher with slow ions and up to 250 times higher than the molar analyte concentration; for analyte ions the peak-to-background ratios were higher using slow projectiles; the fraction of carbon-rich collisionally formed molecular ions was much higher with fast projectiles. Sample aging in vacuum for up to five weeks strongly reduced the yield of protonated analyte molecules ejected by slow ion impact, but not of deprotonated species. Hence protonation seems to correlate with sample "wetness" or the presence of volatile proton-donating additives.

Angiotensins↗
PubMed2000

Hyposensitivity to amphetamine following exposure to chlorphenvinphos--protection by amphetamine preexposure.

We investigated the effect of an acute exposure to chlorphenvinphos (CVP), an organophosphate anticholinesterase, on amphetamine-induced open-field locomotion in rats. CVP was administered in a single i.p. dose of 1.0 mg/kg (1/10 of the LD50). All animals were challenged with 1.0 mg/kg amphetamine (AMPH) three weeks after the CVP exposure, i.e. after a time sufficient for acetylcholinesterase recovery. Some rats were also given AMPH three weeks before the CVP exposure. In rats challenged with AMPH only once after the CVP exposure, AMPH-induced open-field locomotion was significantly reduced. Such an effect was not observed in rats given AMPH three weeks before the CVP exposure. The results suggest that a single CVP exposure may result in persistent dopaminergic hyposensitivity, and that an amphetamine pretreatment may protect the rat against this effect.

Amphetamine↗
PubMed2000

Mortality of workers at two asbestos-cement plants in Poland.

To assess mortality rate among workers occupationally exposed to asbestos, cohort studies were carried out in two asbestos cement plants operating since the 1960s. Asbestos cement sheets for roofing and siding have been manufactured there, using mostly chrisotile, and since 1985 also crocidolite for pressure pipes. In all, the cohort comprised 3,220 workers, including 2,616 male workers. Subject to consideration were the workers employed for at least three months in the period between the onset of the production and 1980. The vital status of the subjects was traced up to 31 December 1991. The availability of the cohort was 96.8%. Workers' mortality was analysed using standardized mortality ratio (SMR). The reference group was the general population of Poland. In the male cohort, 385 cases of death were recorded. Statistically significant excess of mortality from large intestine cancer (7 cases, SMR = 264) and pleural mesothelioma (5 cases, SMR = 2846) was found. In male workers who died from pleural mesothelioma the work history ranged from 12 to 26 years. An excess mortality from pleural mesothelioma was also noted among the female workers (2 cases, SMR = 11,275). No malignant neoplasms of other locations produced significant excess mortality either in the male or female workers.

Adult↗
PubMed2000

[Quantitative evaluation for risk assessment of neoplasms caused by exposure to chemical substances].

This work is based on the assumption that work safety and hygiene inspectors or a work hygiene inspectors in sanitary and epidemiological station will not develop their own dose-response models on the basis of background data. They should be equipment with a tool allowing them to assess a given risk in the most simple way. Dose-response models for assessing cancer risk induced by carcinogenic chemicals are presented in the "Guidelines on health risk assessment of carcinogenic agents" published since 1995 by The Nofer Institute of Occupational Medicine in Łódź. Nevertheless, it seemed advisable to gather in one publication all models published thus far, and by adding relevant comments and necessary formulas for calculations, produce a simple set of practical rules of risk assessment. All models already published in Guidelines may be divided into two groups: linear and non-linear models. In addition, among linear models one may differentiate those for asbestos dust exposure because of different nature of the relationship between the extent of exposure and likelihood of cancer occurrence. The models are given in three tables under the following headings: linear models for 21 chemicals, non-linear models for 12 chemicals and linear models for asbestos. There are also included formulas that allow to convert dose into concentration and concentration into dose, and occupational exposure into equivalent exposure over the course of a lifetime, as well as conversion coefficients enabling the use of animal experiment results in the assessment of human risk.

Asbestos↗
PubMed1999

[The causes of increased risk for lung cancer in the pulp and paper industry workers. The effect of smoking and exposure to chemicals].

An analysis of mortality in a cohort of workers employed in the pulp and paper industry, carried out by the authors of this presentation several years ago, indicated an increase of 22% in the risk of mortality from lung cancer. This risk decreased by only 4% after taking account of smoking. The results obtained then were considered as sufficient to undertake further studies aimed at identifying specific occupational factors responsible for an increased risk for mortality from lung cancer in the population under study. The nested case-control study, in which cases (of lung cancer) and controls were selected from the same cohort observed earlier, was approved as the most suitable method for achieving the aforesaid aim. The study covered 79 cases of deaths from lung cancer confirmed by histological and cytological or radiological examinations, and 237 'healthy' controls matched in the ratio of one to three, taking into account gender, date of birth and date of employment. A group of experts carried out in-depth analysis of exposure to harmful factors in each case of death and in each control. Using a questionnaire, specially developed for this purpose, detailed data on smoking habits among persons under study were collected. Odds ratio was used as a measure of a relative risk for death from lung cancer. A crude relative risk and risk adjusted by eliminating the effect of smoking, applying the model of conditional logistic regression, were calculated for individual exposure factors. Smoking proved to be a significant causal factor responsible for the development of lung cancer in the cohort studied. That was evidenced by relative risk accounting for 12.9 for smokers in relation to non-smokers and an enhanced risk with the increasing number of cigarettes smoked daily, the number of smoking years and an accumulated dose. The study does not confirm a hypothesis that chemical factors specific of the pulp and paper industry exert a significant effect on the risk of death from lung cancer. Odds ratios, crude and adjusted for smoking, were lower than one in all distinguished categories of exposure.

Adult↗
PubMed1999

[Incidence of occupational diseases in Poland].

The paper is aimed at presenting the incidence of occupational diseases in Poland. The analysis was performed on the basis of the information included in 'occupational disease certificates'. All sanitary and epidemiological stations throughout the country are committed to send these certificates to the Central Register of Occupational Medicine in The Nofer Institute of Occupational Medicine in Lódź. The incidence of occupational diseases during the three recent years (1996-97-98) was the subject of a thorough analysis. In all, 11,318, 11,685 and 12,017 cases of occupational diseases, respectively were registered over those three years. The corresponding rates were 116.0, 116.9 and 117.3, respectively per 100,000 people employed. In 1998, diseases of the voice organ predominated (30.4%) of all occupational diseases) and they were followed by hearing impairment (28.2%), infectious and parasitic diseases (9.9%), pneumoconioses (8.2%), dermatoses (6.4%), vibratory syndrome (2.9%) and poisoning (2.5%). These disease categories constituted over 88% of all occupational diseases registered in that year. Diseases of the voice organ which showed the greatest growth dynamic were mainly diagnosed among teachers. Neither in the United States nor in the member states of the European Union, this pathology is included into the list of occupational diseases. In view of high rates of its incidence in our country it has become one of essential problems of occupational medicine. In Poland, particular attention is paid to infectious and parasitic diseases among which hepatitis occupies the first place (65%), mostly among health service workers. The decrease in hepatitis incidence observed in the 1990s has been due to an intensive vaccination programme in this group of workers. The incidence of occupational hepatitis became rather stable and accounted for 940 cases per year, however the incidence of hepatitic C increased at the same time. Lower rates of incidence of 'classic' occupational diseases, such as poisoning, pneumoconioses or vibratory syndrome are a positive observation. It is also interesting to note that the rate of occupational diseases diagnosed in advanced stage has also diminished. When analyzing occupational diseases one should bear in mind that the majority of pathologies already diagnosed result from long-term effect of exposure to harmful factors. In all, 93% of cases of occupational diseases emerged after a ten-year exposure. The highest rates, taking account of sections of activity, were found in mining and quarrying, health service, agriculture, hunting and forestry.

Adult↗
PubMed1999

[Quantitative assessment of cancer risk following epidemiological studies].

The role of data derived from epidemiological studies in the quantitative assessment of cancer risk has been constantly growing. That results from the fact that epidemiological studies are performed directly on humans so that it is possible to avoid bias very often associated with methods of extrapolation between animals and humans. Moreover, a slow but continuous increase in the number of well designed epidemiological studies with results which can be used to estimate dose-response relationship is being observed. In this paper, the methodological foundations of cancer risk modelling on the basis of epidemiological studies are discussed, and the dose-response relationship based on epidemiological study carried out in an occupational cohort of workers employed in a pulp and paper plant was estimated. The epidemiological study was performed by the team of the Department of Epidemiology, The Nofer Institute of Occupational Medicine, Lódź. Lung cancer was adopted as the effect of occupational exposure. In oder to estimate the increase in cancer risk induced by occupational exposure, the risk for the whole occupational life was calculated by employing the methods of competitive risks, essential relative risks were modelled using Poisson means for data divided into groups, and a Cox proportional-hazards model was used for single data. The analysis indicated, that the data from epidemiological studies render it possible to carry out a more thorough investigation as compared to data obtained from animal experiments. As to the cohort under study, a certain effect of age at which workers enter into exposure on lung cancer risk was observed. A risk 'outfit' the workers bring in at the beginning of their employment is clearly visible in older age groups. A general conclusion drawn from the study may be formulated as follows: epidemiological studies play a major role in assessing the effect of working conditions on the increase in the morbidity risk, however, they are not a panacea for all the problems emerging in the cancer risk assessment in exposed persons. Therefore, information obtained from epidemiological and toxicological studies should supplement and reinforce one another, and data from both sources should be used to obtain the best possible characteristics of risk cancer in humans.

Adult↗
PubMed1998

[Application of BMD models in quantitative evaluation of carcinogenic risk].

The characteristics of the relationship between the exposure level and the incidence of harmful health effects is a general objective of assessing health risk related to chemical exposure. A real dose-response relationship, particularly for low doses, is usually unknown thus it can only be deduced on the basis of biological and statistical considerations. Low dose risk estimation requires extrapolation beyond the range of data observed. Nowadays, quantitative risk assessment encounters certain duality as linear models are mostly used in evaluation of environmental exposure, and nonlinear models are most frequently applied in occupational exposure. Bearing in mind that the assumption on the dose-response linear relationship is an apparent simplification built on our lack of knowledge of carcinogenic mechanisms, it seems that the proposal of the US Environmental Protection Agency (US EPA) to use benchmark dose methods (BMD) for exposure effects manifested by neoplasms, is the compromise between a conservative approach of the EPA towards risk modelling resulting from the limited knowledge of these mechanisms and lack of criteria for selection of nonlinear models. In the case of carcinogenic risk assessment, this solution involves the identification of so called 'cut off point' by applying relevant statistical models. The cut off point indicates the exposure level that contributes to the increase in risk by 10%, 5% or 1%. Another possibility is to use interspecies extrapolation methods for the cut of point modification, and then draw a line between the cut off point and the beginning of the system of co-ordinates. Since it is not feasible to apply a complete BMD methods for certain chemicals (e.g. bezo(a)pirene), not because of chemical properties, but due to insufficient experimental experience, it is proposed to use the method of sticking together a straight line and a curve in relation to a two-grade curve and not to its confidence limitation.

Carcinogens↗
PubMed1998

[Health effects of occupational diseases diagnosed in Poland during the years 1990 and 1994].

The study was carried out on the material of 15,136 occupational diseases that accounted for 71.9% and 65.6% of all cases detected in 1990 and 1994, respectively. The analysis focused on the selected health effects of occupational diseases, such as sickness absenteeism, the transfer to other workposts, the percentage of health impairment and related single recompensation as well as disability pension. The study helped to draw many conclusions of great value, and disclosed major pathologies and their causes responsible for the range of related health effects. Long-term sickness absenteeism, high percentage of health impairment and related consequences for the country's economy (single recompensations and growing number of disability pensions paid due to occupational diseases), and low proportion of transfers to safe workposts were most striking among the effects in question. The study also contributed to initiating the establishment of the data base and the development of the system for data collection and analysis of information on health effects of occupational diseases in Poland.

Absenteeism↗
PubMed1998

[Data processing computer system for evaluation of health effects due to occupational diseases diagnosed in Poland].

General consequences of occupational diseases for both employees and the country's economy have been known for many decades. Nevertheless there were no legal instruments and financial means to carry out studies leading to a comprehensive evaluation of health effects induced by occupational diseases diagnosed in Poland. Only recently, the legal basis has been provided by the revision of the regulations on occupational diseases (Official Journal of the Ministry of Health and Social Welfare no 9, heading 51, 1989), and the financial means allocated according to the Governmental Strategic Programme (SPR-1) for the years 1995-1998. The objectives of the study and the results obtained have been presented in another publication. Here the authors concentrated on some aspects of data collection and their analysis. An essential element in the establishment of data base on health effects of occupational diseases was its integration, namely the number of diagnosed occupational disease had to correspond with the entity in the Register of Occupational Diseases. Such an approach helped to avoid including in the base all metrical data, as information on effects of occupational diseases was collected exclusively for persons with detected and diagnosed occupational disease, which had to be previously placed in the Register of Occupational Diseases. The correctness of data input and the data analysis were carried out outside the Paradox system. The analysis of histograms of characteristics under study and the explanation of departing values were employed to evaluate the freedom from bias, and the statistical package for social sciences (SPSS) was used to analyse the data.

Computer Systems↗
PubMed1998

[Evaluation of reproductive disorders in men occupational exposed to lead].

The objective of the study was to define the prevalence of reproductive disorders in men occupationally exposed to lead in concentrations occurring usually in the work environment. The period of time preceding the conception in couples in which men were occupationally exposed to lead was adopted as the measure of the disorder. A cross-section survey was performed. Men of selected plants of Upper Silesia and Głogów responded to questions included in the questionnaire regarding age, education, occupation, occupational exposure, health condition, addictions, the situation in the family as well as questions concerning the respondent's spouse (age, education, occupation, addictions, health condition). The blood lead concentrations in persons exposed to this metal in the period preceding the conception were defined on the basis of medical data stored by the plant occupational outpatient clinics. The control group consisted of workers of the metallurgic industry, living in Lódź or its vicinity, and non-occupationally exposed men living in Silesia. In total 341 exposed men and 510 non-exposed controls participated in the study. The investigated groups were rather homogeneous as to the age of those under study and their spouses, education, addictions and the number of children. The analysis of the survey results indicated that in 5% of couples in the control group the time before conception exceeded one year. A similar occurrence of reproductive disorders was found in couples in which man was occupationally exposed to lead. The proportion of couples with reproductive disorders in this group (regardless of the size of Pb exposure) was 6%. The stratification of the Pb-exposed groups, taking into account the exposure size in accordance with the WHO criteria (group 1-220 micrograms/l, that is below the accepted value above which the ZnPP level increases; group II-PbB 200-400 micrograms/l that is up to the level recommended as the highest level for the population occupationally exposed to lead; and group III-PbB above 400 micrograms/l) allowed the analysis of the frequency of reproductive disorders depending on the size of the exposure. The percentage of couples with delayed conception accounted for 4.5% in group I; 8.7% in group II, and in group III did not differ significantly from that in the control group. These results show that men's occupational exposure to lead below allowable concentration in the biological material (500 micrograms/Pb/l blood in Poland or 400 micrograms/Pbl recommended by WHO) does not pose the risk for prolonged period preceding the conception in their partners.

Adult↗