Biomedical subjects

M Sarić

Publications and source records attributed to M Sarić.

At least 19 recordsLinked to original sources

PubMed1994

Determination of active pellets' position in the selectron-HDR vaginal tube using a therados RFA-3 water phantom system.

The method for determination of the active pellets' position in the Selectron vaginal tube is shown. A special steel cap shielding with narrow window mounted above the Therados RFA-3 semiconductor detector was constructed. By scanning along the Selectron line vaginal tube in air and water, for an appropriate distance with mild dose gradient, the actual active pellets' positions can be determined. The resolution was higher during scanning in the air than in water. The minimum number of tries for checking the whole system depends on the total number of pellet sources in the main safe, and the number of active pellets used. Advantages of this method, compared to other conventional methods for determination of the Selectron-HDR source positions, are associated with high resolution and capability of repetition without movement of the tube during checking procedure.

Brachytherapy↗

PubMed1994

Ornithine decarboxylase in Pneumocystis carinii and implications for therapy.

Pneumocystis carinii pneumonia (PCP) can be treated with eflornithine (difluoromethylornithine, DFMO, Ornidyl), a competitive irreversible inhibitor of ornithine decarboxylase (ODC), a key enzyme for polyamine biosynthesis. Because ODC has been reported to be absent from P. carinii, it has been assumed that eflornithine affects P. carinii only indirectly, by affecting host polyamine biosynthesis. If this is true, then improvements in the selectivity of antipolyamine therapy for PCP would be limited. Since the presence of ODC in P. carinii is an important issue, a new search for this enzyme was made. Not only were initial assays negative, but P. carinii extract reduced the background catalytic action of pyridoxal-5'-phosphate, the coenzyme required by the enzyme. This suggested the presence of an inhibitor, which was further supported by the observation that a P. carinii extract could suppress a source of known ODC activity. The inhibitory activity could be removed by a desalting column or by dialysis, allowing detection of P. carinii ODC. Indirect evidence indicates that the inhibition is only apparent and is caused by unlabeled ornithine in the extract of P. carinii which interferes with the radiolabel-based assay system. P. carinii and host ODCs respond differently to changes in pH. P. carinii ODC is much less susceptible to inhibition by eflornithine than host ODC. The presence of ODC in P. carinii suggests that P. carinii ODC is the target of eflornithine and that P. carinii ODC may have sufficiently specific properties that inhibitors with improved selectivity against P. carinii ODC could be identified.

Animals↗

PubMed1994

Malignant tumors in an area with an asbestos processing plant.

Incidence rate of malignant tumors of the lung/bronchus, pleura, larynx, pharynx, and peritoneum during the period 1974 to 1987 was studied in a Croatian coastal area with an asbestos processing plant which started to operate in 1954. The study area covers 169 km2 with 11,270 inhabitants: 5590 men and 5710 women (average number during the study period). The calculated number of inhabitants aged 35 and older was 4639 (41.1%), 11.5% were aged 60 or older, and the average age was 32 years. Over the observed 14-year period there were 51 cases of malignant tumors, 40 in men and 11 in women: lung/bronchus cancer, 36-29 men and 7 women; mesothelioma, 5-2 men and 3 women; laryngeal cancer, 5 men; pharyngeal cancer, 4-3 men and 1 women; and peritoneal cancer, 1 man. The results of the study showed that the incidence of lung/bronchus cancer in the studied population was half that in Croatia. There were also fewer malignant tumors of the pharynx and peritoneum in this area than in Croatia. On the other hand, the incidence of primary tumors of the pleura was more than 5 times as high and of laryngeal tumors more than 2 times as high as in Croatia. Evaluation of the data showed that distance from the source of emissions was not crucial for the development of tumors. The incidence of the tumors in the town with the asbestos factory was the lowest. Among and within different towns/villages the tumor incidence varied; in some the observed rate was higher than the expected rate. A more detailed analysis indicated a possible influence of the relief and prevailing wind direction on the environmental contamination with asbestos from the emissions source and consequently on an uneven distribution of the tumor incidence among separate settlements in the area under study.

Adult↗

PubMed1993

Can the occurrence of bronchial asthma in potroom workers be prevented?

Bronchial reactivity was evaluated in a group of 35 workers at preemployment examination using the metacholine test. Three workers showed an increased bronchial reactivity, the rate being in accordance with the previous experience. Ten randomly chosen subjects with normal reactivity, who were engaged as potroom workers, were followed up during a two-to-five-year period. None of them experienced any significant respiratory complaints and their bronchial reactivity also remained normal. Only one worker had a borderline finding (PD20FEV1). Although selection at preemployment medical examination is a measure that has to be used only exceptionally, based on the finding obtained by non-specific bronchoprovocation challenge it seems that it can be recommended in the case of that particular exposure.

Adult↗

PubMed1993

[Criteria for recognizing asbestosis as an occupational disease].

The commentary deals with the development of asbestos disease, its cause and latency, especially in connection with the carcinogenic effect of asbestos exposure. Diagnostic criteria and the approach to disability assessment are summarized. Legislative and organizational aspects in the assessment of the disease as occupational are discussed.

Asbestosis↗

PubMed1992

Epidemiology of Balkan endemic nephropathy.

The first outbreak of Balkan endemic nephropathy (BEN) was reported between 1955 and 1957, initially in Serbia and soon afterwards in Croatia and in Bosnia and Herzegovina. The disease appears to be of a focal nature. In Yugoslavia at least six foci are known, generally along major rivers of the Danubian river basin, in areas that have often been flooded in the past and even today suffer from high ground waters. The prevalence rate of the disease is reported to be between 2 and 10%. In the endemic area of Croatia, a systematic survey of 'in-the-field' cases of the disease since 1975 has shown a prevalence between 0.5 and 4.4%. When suspected cases are also included the prevalence rises to 20% or more. Specific mortality (based on official statistics) during the period 1957-1984 averaged 1.54/1000 per annum, but some studies have shown that mortality is actually more than twice as high as this figure. More women are affected than men; women also more frequently die of BEN than men. Lethality is extremely high. A striking feature of BEN is the familial occurrence of the disease. Incidence does not seem to be connected with ethnic group differences. Immigrants into the endemic area may also contract the disease. An increased incidence of malignant tumours of the urinary tract has been recorded in populations living in endemic areas. Epidemiological characteristics suggest that the disease is contracted in the domestic situation, or possibly from other family members. Factors to be considered are food, water or long close contact. It is also possible that the disease is contracted outside the house, in connection with farming activities, since the affected persons are almost exclusively farmers.

Adult↗

PubMed1992

Biphasic lung diffusing capacity: detection of early asbestos induced changes in lung function.

Asbestos related changes in the single breath carbon monoxide diffusing capacity (DLCO) were longitudinally analysed in 14 subjects exposed predominantly to chrysotile asbestos in an asbestos cement factory. These subjects were examined annually over the past nine years; their lung function was initially characterised with increased DLCO as the sole functional abnormality and they had normal chest radiographs. The radiological examination included a chest x ray film and, in the past two years, high resolution computed tomography (HRCT). A biphasic DLCO change was found: an initial increase followed by a relative decrease. The increase in DLCO was mainly caused by an increase in the membrane component (Dm). Indomethacin treatment applied after the sixth annual follow up significantly reduced DLCO and Dm. The decrease in DLCO correlated well with the parenchymal abnormalities found on HRCT, whereas the chest x ray film profusion score for small opacities (ILO classification) was unchanged. In conclusion, the data suggested that, as well as the absolute values of pulmonary function tests, the measurement of progression of functional parameters is essential in the assessment of pleural and parenchymal disease of the lung related to exposure to asbestos. High resolution computed tomography is suggested as the radiological method of choice in subjects with an isolated decrease in DLCO. Exposure to asbestos can be associated not only with a reduction in DLCO, but also with a temporary increase in DLCO caused by a subclinical inflammatory reaction.

Adult↗

PubMed1992

Psychological and ergonomic aspects of work with video display terminals.

Forty-nine operators of video display terminals were administered a questionnaire on subjective complaints in connection with work conditions. Measurements of non-ionizing and ionizing radiation emissions during normal operation of video display terminals showed them to be within permissible levels. A detailed ergonomic analysis of equipment and workstations was also performed. Results showed a high occurrence of subjective complaints, significant differences between age subgroups in a few variables, and significant correlation between sets of variables of some perceived ergonomic features and subjective complaints.

Adult↗

PubMed1992

[Work-related diseases].

The different causal factors of work and work environment which contribute to the development of work-related diseases are discussed. The diseases such as locomotor disorders, chronic non-specific respiratory diseases, arterial hypertension, disorders connected with psychosocial factors and the use of video display terminals are separately analysed. Special emphasis is placed on the importance of epidemiological and clinical approach in the prevention and control of work-related diseases with regard to the different causal factors. Criteria for diagnosis of work-related diseases are suggested to serve as basis for preparation of the List of work-related diseases.

Humans↗

PubMed1991

Methods for integrated exposure monitoring of lead and cadmium.

An international pilot monitoring study on exposure to lead (Pb) and cadmium (Cd) has been implemented in Beijing, Yokohama, Stockholm, and Zagreb as part of the UNEP/WHO human exposure assessment locations (HEAL) Program. The main objective was to develop and test methods, including methods for quality assurance, for monitoring of personal exposure to Pb and Cd. The study included analytical training for Pb and Cd in blood, air filters, dust, diets, and feces, as well as exposure monitoring activities in small groups of nonsmoking women, 23-53 years of age, during 7 consecutive days. Airborne particulates, duplicate diets, feces, and blood were collected. An extensive quality assurance program was implemented in order to assure the reliability and comparability of the monitoring data. The main problem in the sample collection was associated with the air monitoring. The pumps were noisy, and the batteries had to be recharged every 6-8 hr. Collection of duplicate diets during 1 week gave good estimates of average dietary intakes of Pb and Cd. The metal contents in feces were found useful for evaluation of total peroral intakes. The methods used made it possible to demonstrate that the diet was the main source of Cd exposure at all the HEAL sites.

Adult↗

PubMed1991

Bronchial hyperreactivity in potroom workers and prognosis after stopping exposure.

A group of 30 potroom workers who developed an asthma-like syndrome during their work in the electrolytic extraction of aluminium (Alu-Swiss process with prebacked anodes) was followed up after stopping exposure. Subjective respiratory complaints were registered and a non-specific bronchial reactivity test using methacholine was performed once or twice during the follow up period (1984-9). After transfer to other work most workers either had an improvement in respiratory symptoms (60%) or even normalisation (27%); only 13% did not show changes. Bronchial hyperreactivity remained unchanged in 67% of workers, was less pronounced in 13%, normalised in 13%, and deteriorated in 7%. Smoking habits, atopy, and duration of exposure did not seem to have influenced the results obtained. No significant correlation was found between duration of exposure and the speed of onset of respiratory symptoms and the later prognosis of the syndrome. Based on the information collected during the period of observation it appears that reactive airway dysfunction syndrome, once induced, has a tendency to persist. An improvement in subjective complaints may be expected, however, after stopping exposure.

Adult↗

PubMed1991

Diet patterns and health problems: diet in southern Europe.

The diet of the populations in southern Europe, particularly those living in the Mediterranean areas, was characterized by a relatively higher consumption of fish, olive oil, vegetables and fruit and by a lower consumption of meat and animal fat. In terms of nutrients the most significant difference between the Mediterranean type of diet and the diet of continental and northern European populations was in the consumption of saturated and monounsaturated fatty acids and to a lesser degree in the intake of protein, sugar and alcohol, as well as in regard to the dietary fiber content. Since the Mediterranean populations have shown a lower total mortality rate as well as a specific mortality from coronary heart disease (CHD) which in part could be explained by their dietary habits, the Mediterranean diet has often been proposed as a prototype on which dietary measures for the prevention of CHD in populations should be developed. However, more recent data indicate that in the last 20 years the food pattern of the Mediterranean populations was subjected to substantial changes, particularly in regard to the increase in meat and dairy product consumption which in turn has resulted in an increase in the percentage of energy of saturated fats and which has also affected the ratio of monounsaturated to saturated fatty acids. These changes have also affected some of the risk factors of CHD in those populations.

Diet↗

PubMed1991

[Hematologic changes in workers exposed to radio wave radiation].

Haematological parameters were measured in 43 radar operators employed in air traffic control occupationally exposed to microwave radiation of low intensity over a period of four years. Exposure to heat, soft X-ray radiation and noise were within maximally allowed limits. The haematological changes included a decreased number of erythrocytes, reticulocytes, platelets, segmented granulocytes and monocytes, and an increased number of leucocytes and lymphocytes. The changes were not pathologically significant and most of them were reversible.

Adult↗

PubMed1991

Assessment of exposure to lead and cadmium through air and food in inhabitants of Zagreb.

Exposure to lead and cadmium was monitored in a group of 17 non-smoking women in Zagreb. The monitoring included measurement of the intake of the two metals via air and the diet during a period of seven days. Duplicate daily diets and air filter samples were collected for analysis of lead and cadmium. To check the intake of lead and cadmium with the daily diet, faeces were collected and analysed. The mean gastrointestinal absorption was estimated to be 4.9 micrograms/day for lead and 0.75 micrograms/day for cadmium. These values were derived from faecal data which were assumed to be more reliable. The daily absorption through inhalation estimated on the basis of air analysis was 2.7 micrograms for lead and 0.03 micrograms for cadmium.

Adult↗

PubMed1991

[Circadian variation in alertness, readiness for work and work efficiency].

Among various rhythmic processes with different frequencies (periods), which are present in the human organism, for normal functioning the most important are the rhythms with a cycle length of about 24 hours (termed circadian rhythms). Circadian rhythms have been confirmed at all levels of physiological functions: from subcellular and cellular mechanisms, to the organic systems and organism on the whole. In normal everyday circumstances the rhythmic processes in the human organism are synchronised with the rhythmic processes in the environment. The external rhythmic variations support internal synchronisation between various rhythms, and in that way make it possible for the organism to better adapt to the environment. The sleep--wake rhythm is inverted during night work: the worker has to work in the period of low activity level, and sleep during the day, when he is usually active and alert. In order to work in shifts the worker has to adapt to such disruptions of the sleep--wake pattern. Tolerance to shift work was found to be associated with some features of the worker. The measurement of such features could serve as determinate of interindividual differences in shift work tolerance level.

Body Temperature↗

PubMed1991

[Occupational medicine in European countries and in Yugoslavia].

A recent publication on occupational health services in European countries prepared by the World Health Organization is reviewed. On the basis of guidance by the international organizations, the overall objectives of occupational health services are embodied in principles which are implemented in various ways in the practical activities undertaken in each country. The functions of occupational health services, organizational models, coverage, personnel, support systems (industrial hygiene, ergonomics, psychology, clinical occupational medicine) as well as research, training and funding are discussed. Comparison is made with the actual situation and development of occupational health service in Croatia with special reference to the conclusions drawn at a round table discussion organized by the Association of Occupational Health of the Croatian Medical Society in Pazin, in April 1991.

Europe↗

PubMed1990

Deferoxamine and eflornithine (DL-alpha-difluoromethylornithine) in a rat model of Pneumocystis carinii pneumonia.

The iron chelator deferoxamine and the polyamine biosynthesis inhibitor eflornithine (DL-alpha-difluoromethylornithine) were examined for anti-Pneumocystis carinii activity in the rat model of P. carinii pneumonia. The activity of deferoxamine at 250, 500, and 1,000 mg/kg given intraperitoneally provides evidence that iron chelation is a promising novel approach to P. carinii chemotherapy. Results with eflornithine at 2, 3, and 4% in drinking water confirm and extend previously reported activity in the rat model.

Animals↗

PubMed1990

[Physical stress and bronchial hyperreactivity in aluminum-processing workers].

A possible impact of physical load on the degree of bronchial hyperreactivity was studied in actual working conditions among the workers in an aluminium electrolysis plant. Respiratory irritants present in the working environment were also determined. The study was conducted in two groups of workers: one, of 34 workers who had been previously categorized as having respiratory symptoms and the other, of 19 control workers without symptoms. Both groups were matched by age, height, weight and years of service in the plant. All workers underwent a progressive submaximum exercise test of 300-600-900 kpm/min load on a bicycle ergometer. Simultaneously a continuous monitoring of heart function was performed. Heart rate, blood pressure and lung function parameters: FVC, FEV1, PEF, MEF25, MEF50, MEF75 and FEV1/FVC% ratio were measured before and 18 minutes after exercise. The results of the study showed that physical load and concurrent exposure to respiratory irritants had no impact on bronchial hyperreactivity in either group of workers. However, the exercise test demonstrated the existence of appreciable individual differences within the two groups.

Air Pollutants, Occupational↗