Тhe influence of peers over adolescents' sexual conduct in Macedonia.

UNLABELLED: The main objective of the study was to investigate the influence of peers on the main determinants of adolescents' sexual conduct in Macedonia, in order to identify both risk and protective factors. METHODOLOGY: Data were obtained through a quantitative cross-sectional survey using a standardized paper-and-pencil self-administered questionnaire prepared for the WHO "Health Behaviour in School-aged Children" study. The study was conducted among 1226 secondary school students aged 15 and 17 (1st and 3rd year) from 10 different secondary schools in Macedonia. Peer contact frequency and peer group activities were examined as independent explanatory variables, and prevalence of sexual activity, age of onset of sexual activity, number of sexual partners and use of contraception during the first and recent sexual intercourse as dependent variables. RESULTS: Peer contact frequency has shown to be a protective factor with regard to the age of onset of sexual activity and use of contraception during the first and recent sexual intercourse, a risk factor with regard to the prevalence of sexual activity, whereas it has no influence on the number of sexual partners. Peer group activities have no influence on the prevalence of sexual activity and the use of contraception, but direct 'face to face' conversation is a protective factor regarding the age of onset of sexual activity and the number of different sexual partners. Chatting over the Internet has shown to be a risk factor regarding the number of sexual partners, while 'hanging out' has no impact on the determinants of sexual conduct. CONCLUSIONS: Friends may protect adolescents from risk activities and peer influence may be used in public health interventions aimed to improve adolescent sexual and reproductive health.

Gender analysis of sexual behaviour of senior high-school students in Skopje, R. Macedonia - cross-sectional study.

UNLABELLED: (Full text is available at http://www.manu.edu.mk/prilozi). The aim of the study was to assess the gender influence on the main determinants of sexual behaviour of senior high-school students in Skopje, R. Macedonia (prevalence and age of onset of sexual activity, duration of the relationship before and the contraceptive method used during the first sexual intercourse, and number of lifetime sexual partners). METHODS: After ensuring privacy and confidentiality, a cross-sectional study was carried out in Skopje by enrolling 310 high-school students (49.7% males, 49% females, 1.3% unknown) from 5 randomly selected high-schools, from the 4th grade, using a 32-item paper-and-pencil self administered questionnaire. RESULTS: The prevalence of sexual activity was higher among boys than girls (when reaching grade 4 of the study 62.7% of the boys and 26.7% of the girls are sexually active) (p < 0.01). In addition, a significant gender difference was found in the following: the mean age of onset of sexual activity is 16 years for boys and 17 years for girls; concerning the duration of the relationship before the first sexual intercourse 33% of the boys and 2.5% of the girls had experienced one-night stand relationship (p < 0.01); and concerning the number of partners, having four or more sexual partners was reported by 29.8% of the boys and 5% of the girls (p < 0.01). Of those sexually non-active, 62.5% of the boys and 15.5% of the girls did not start with sexual activity because they did not have a chance (p < 0.01); 17.9% of the boys and 79.1% of the girls felt unprepared (p < 0.01). CONCLUSION: The data indicates substantial gender differences in sexual initiation patterns and sexual conduct. Boys and girls are vulnerable at different times in their development and hence need to be reached with different public health interventions for improving their sexual and reproductive health, adapted to local cultural and gender norms. Key words: Macedonia, high-school students, sexual behaviour, gender.

Epidemiological characteristics of the metabolic syndrome in apparently healthy persons.

The risk factors that define the metabolic syndrome lead to an accelerated development of atherosclerosis, cardiovascular diseases in apparently healthy persons. The goal of the research is determining the prevalence of the metabolic syndrome as well as the participation of the risk factors that define this condition in apparently healthy persons. The metabolic syndrome is defined according to the National Cholesterol Education Program Expert Panel. The prevalence of the metabolic syndrome in the examined population, aged 53 +/- 8, is 62 (39.7%). In the group of subjects that have the metabolic syndrome,the largest number of subjects had 3 risk factors and only 5 subjects had 5 risk factors. With the increase of the number of components of the metabolic syndrome, all the observed parameters of the metabolic syndrome also increase, while the level of HDL decreases. In all the examined groups of subjects, the low level of HDL-H is the most present metabolic risk factor, while in the groups of subjects that have the metabolic syndrome the hypertension is the second most present factor, and the waist circumference is the least present factor. According to our research, the prevalence of the metabolic syndrome in apparently healthy persons that have a sedentary life style is 39.7%. In all the subjects the low level of HDL-h is the most present, and in the subjects with the metabolic syndrome compared to subjects that do not have this syndrome the frequency of all the components of the metabolic syndrome is statistically considerably higher.

Density and distribution of population in FR of Yugoslavia.

PIP: Population trends in Yugoslavia, consisting of the republics of Serbia and Macedonia, are analyzed over the period 1948-1991. The focus is on changes in spatial distribution, density, and concentration. The author notes a trend toward the concentration of population in urban areas and the increasing depopulation of the more remote rural areas.^ieng

[Evaluation of occupational risk for workers producing polyvinyl chloride resin pipes, profiles and fixtures]. / Otsenka na profesionalniia risk na rabotnitsite v proizvodstvo na trubi, profili i fitingi ot polivinilkhloridna smola.

Studies are performed on work and hygienic conditions in the production of pipes, profiles and fittings from polyvinylchloride resin, in relation to the toxic factor. Concentrations above TLV are established for vinylchloride, vinylchloride resin dust, phthalates and lead aerosols. Complex clinico-laboratory examinations are carried out on 133 workers, as special attention is paid to the nervous system, liver function, cardio-vascular system and the skeleton system. In 15 workers are established data for toxic effect of vinylchloride, and in other 5 workers - toxic pneumosclerosis, which is a result both from vinylchloride and vinylchloride resin dust. Hygienic and medico-preventive measures are developed.

[The occupational risk in the manufacture of mineral pigments and iron oxide dyes]. / Profesionalen risk pri proizvodstvo na mineralni pigmenti i zhelezno-oksidni boi.

The mineral pigments and ferric oxide dyes are used on a large scale in the paint and varnish industry, in building, chemical industry, polygraphy etc. For their production as basic raw materials are used lead, chromium and iron compounds. The concentrations of the toxic and accummulating lead and chromium in the air of the work environment surpass MAC and create most frequently "especially unfavourable" conditions of work. In all industrial processes the leading unfavourable factor is the chemical combined with unfavourable physical factors and overstress on the locomotor system. Changes were established in the organism of examined workers as result from the chronic effect of the factors of the work environment of the peripheral blood, digestive, nervous system and the skin. In view of reducing the risk of exposure to the toxic chemical factor it is imposed to take measures for sanitation of the work environment.

[New epidemiological study data on the manufacture of divinyl]. / Novi danni ot epidemiologichno prouchvane v proizvodstvoto na divinil.

Complex labour-hygienic studies were carried out on the working environment in divinyl production as well as on the health state of the workers. The leading deleterious factor of the environment are the concentrations of divinyl, hydrocarbons and ammonia above the norms. The latter have been determined by stationary and personal sample collecting. More than half of the workers examined work under labour conditions characterized as "particularly unfavourable" and "dangerous". In comparison with the hygienic characteristic by the middle of 1978-1980, a considerable increase of ammonia concentrations was established. A total of 102 workers have been covered by a complete clinical-laboratory examination. The results have been statistically processed with a view to establishing the correlation between the effect of the deleterious factors of the working environment and the deviations established in the health state of the workers. The following cases could be associated with occupational risk: cases with "positive" and "very likely" chronic ischemic heart disease as well as those with arterial hypertension, gastrointestinal diseases, chronic diseases of upper respiratory pathways with loss of sense of smell to various degrees, the neurological diseases--autonomic-vasal and neurotic syndrome, the cases of contact dermatitis and anemic syndrome.

Combined effect of some physical and chemical factors.

The effect of simultaneous exposure to noise and dimethylformamide (DMF), noise and xylol and also vibration and lead on the metabolism of the myocardium of albino rats was studied. Combined effect of the factors was examined by the method of bifactorial design of the experiment. The animals were exposed to noise, intensity 46, 85 and 95 dB (2 and 4 hours), DMF in doses of 0.25, 1.00 and 5.00 ml . kg-1 (5 days in a week), and xylol in a concentration of 300 mg . m-3 (4 hours, 5 days in a week) for a period of 1.5 months, as also to vibration, intensity 100 Hz, 4 m . sec-2 (2 hours) and lead acetate in a dose of 20 mg . kg-1 (daily for a period of 10 days). The activity of GlDG, SucDG, LDG, G6PDG, G6P-ase, PGM and CytO in the myocardium of experimental and control animals was examined. Disturbances in metabolic and energy processes in the heart muscle were established after both isolated and combined exposure to the effect of the factors. Results of bifactorial variance analysis demonstrate that combined effect of noise and DMF results in not only independent effect of the two factors, but also in their interaction. Isolated effect of two factors (vibration and lead) can be assessed according to the relationship of some enzymes; their interaction can be noticed in GlDG, ATP-ase and G6P-ase.(ABSTRACT TRUNCATED AT 250 WORDS)

[Liver enzyme function and humoral immunity in workers exposed to vinyl chloride]. / Izuchavane enzimnata funktsiia na cherniia drob i khumoralniia imunitet na rabotnitsi, eksponirani na vinilkhlorid.

The work aims at studying the enzyme function of the liver, as well as the humoral immunity of workers engaged in the production of vinyl chloride and polyvinylchloride with proved hepatotropic and Raynaud syndromes. About 191 workers /experimental group/ from the synthesis and polymerization of vinyl chloride and 2 control groups--34 persons from Varna and 54 from G. Traikov were examined. The following biochemical and immunological studies were performed: GOT, GPT, GGTP, alkaline phosphatase, IGG, circulating immune complexes, titer of the complement, cryoglobulins in the serum and identification of the sediments by immunoelectrophoresis. It was established that the immune system was included in the early phases of toxic effect. Disturbances in the enzyme function and humoral immunity were registered both in workers with hepatotropic and Raynaud syndromes.

Effect of carbon disulphide on the cardiovascular system.

Biochemical, histological and electron-microscopic examinations of the heart and the aorta of albino rats exposed to carbon disulphide in concentrations of 10, 50, 100 and 200 mg . m-3 were carried out. Changes in the metabolic and energetic processes in the myocardium and in the quantitative and qualitative characteristics of the connective tissue of the aortal vessel wall were observed. The established disorders follow the dose-effect dependence. The authors studied the effect of carbon disulphide in concentrations of 10 and 50 mg . m-3 on the electrophoretic spectrum of serum proteins, the quantitative and qualitative characteristics of fibrous structures in the myocardium and the aorta of albino rats fed on atherogenic diet (cholesterol, cholic acid and vitamin D2). The combination of carbon disulphide with the atherogenic factor leads to intensification of changes in the cardiovascular system and in serum proteins, observed after independent exposure to either of the factors. The combination of atherogenic diet and 10 mg . m-3 carbon disulphide induced symptoms of intoxication, decreased survival of the animals, and the developing sclerotic process was found to be more severe and to progress more rapidly than in animals subject to atherogenic diet alone. The obtained results testify to cardiovascular effect of carbon disulphide. The observed atherogenic effect of carbon disulphide in low concentrations is most probably connected with its direct effect on the myocardium and the vessels.

[Changes in the biochemical indices of workers exposed to vinyl chloride and dichloroethane]. / Promeni v niakoi biokhimichni pokazateli pri rabotnitsi, eksponirani na vinilkhlorid i dikhloretan.

Complex laboratory investigations were carried out to 280 workers from a plant, exposed to vinylchloride and dichlorethane. Some hematological indices were followed up (hemoglobin, erythrocytes, leukocytes and platelets) and liver function (GGTP, GOT, GPT, AP, OCP and blood glutathione). Again GGTP and blood platelets significance was confirmed as a diagnostic sign of VCh disease. The inhibitory effect of VCh upon the OCP in the workers exposed is confirmed for the first time. OCP is proposed to be included in Instruction 099. A new case of VCh disease was diagnosed, where the combined effect of VCh and dichlorethane is admitted.

[Assessment of the occupational risk to workers engaged in the manufacture of divinyl-styrene rubber]. / Otseniavane profesionalniia risk na rabotnitsi, zaeti v proizvodstvoto na divinil-stirolov kauchuk.

The production of synthetic rubber, one of the varieties of petro-chemical branch in our country, is new and very prospective. The Bulgarian synthetic rubber is synthesized from petroleum products divinyl and styrene. After the hygienic assessment of the technological processes, a complete characteristic of labour conditions was made and the character of the working process was studied of the main occupations of the workers, attending the installations of Synthetic Rubber Plant. The exposure to occupational noxae was determined and the existing occupational risk was evaluated. The toxico-chemical substances, benzene, styrene and divenyl, are with the highest significance among the factors of the working environment. The data on the health state of the workers are reported and recommendations are proposed for the restriction of the effect of the occupational factors.

[Industrial hygiene studies in the production of various fibers and plastics]. / Trudovokhigienni izsledvaniia v proizvodstvoto na niakoi vlakna i plastmasi.

The results from the labour-hygienic and clinical laboratory studies on working environment and workers engaged in production of polyamide (PAS) and polyacrylnitrile fibres (PAN) are summed up as well as in the production and processing of polyvinylchloride resin, polyurethan, polysterene and glass fibre laminates. The main deleterious factors in those productions are the chemical ones: caprolactam, acrylonitrile,tolyl diisocyanate, vinylchloride, styrene, etc. Noise and microclimate are the other unfavourable on-the-job factors. The concentrations of the toxic substances in the air of the working environment are pointed to be far over MAC, in spite of the new plants. Experiments are reported aiming at the determination of the real exposure of the workers - via individual sample collecting and elaboration of BMAC. The measures for the improvement of the conditions of the working environment in the production of synthetic fibres and plastics are summed up as well as the reduction of occupation risk of the workers.

[Histoautoradiographic analysis of the liver of albino rats treated with low doses of vinyl chloride]. / Khistoavtoradiografichni izsledvaniia na cherniia drob na beli plukhove, tretirani s malki dozi vinilkhlorid.

The authors examined experimental albino rats, treated with low vinyl chloride doses via electronmicroscopic autoradiography by marking with thymidine H3. It was established that no blastic processes developed in liver with the low vinyl chloride doses used. THe authors found a certain inhibition of the plastic functions of hepatocytes, manifested by the diminished marking of thymidine H3 in the nuclei of hepatocytes and Kupffer cells, being of essential importance for an eventual development of the blastic processes in liver.

[Prognosis and determination of the threshold of chronic effect of carbon disulfide and styrene]. / Prognozirane i utochniavane praga na khronichnoto toksichno deistvie na serovugleroda i stirola.

Two series of studies were carried out: I--in workers exposed to four different mean annual CS2 concentrations--6 mg/m3; 12 mg/m3; 51 mg/m3 and 247 mg/m3 and II series-in workers exposed to three styrene concentrations--I mg/m3; 40 mg/m3 and 400 mg/m3. The results obtained in series I show the role of the primary toxic effect (inhibition of oxidases with mixed function) and of the adaptation reactions to it with a view to accurate specifying the threshold of chronic CS2 effect. The mathematical expression of the correlation between styrene concentration in air and blood, of phenyl-glyoxylic and mandelic acid in the urine of the exposed subjects enables the prognosis that the threshold of the noxious styrene effect is within the range of 150 mg/m3 to 250 mg/m3. A reduction on CS2 MAC is proposed--from 10 mg/m3 to I mg/m3 and the correction of styrene MAC--from 5 mg/m3 to 30-50 mg/m3.

[Effect of the intermittent and continuous action of dimethylformamide on adaptation processes]. / Vliianie na intermitentnoto i monotonno deistvie na dimetilformamida vurkhu protsesite na adaptatsiia.

Two series of experiments were carried out with 960 mg/kg and 3840 mg/kg DMF, applied dermally to albino rats every second, third day and daily as well. The treatment scheme quarantees equitoxic quantities of DMF with a dynamic observation by the 4th, 8th, 14th and 28th day from the beginning of the exposure and after 14 days of rehabilitation. The complex investigation with integral and specific clinical-laboratory tests revealed a cumulation of the toxic effect with progressing changes in the liver function, better manifested with the intermittent regimes. The dose of 3840 mg/kg induced distinct deviations in the lipid metabolism and serum enzymes. In contact with 960 mg/kg DMF, a phase-state was established during the first terms of observation with the development of adaptation under a monotonous effect and absence of restoration -- mainly in case of intermittent effect. Dermal toxicity of DMF should be given consideration in the assessment of the risk from exposure during production of polyacryl fibres.

[Experimental substantiation of the maximum permissible concentration (MAC) of polyvinyl chloride resin]. / Eksperimentalno obosnovavane na predelno dopustimata kontsentratsiia (PDK) na polivinilkhloridnata smola.

The acute and chronic oral, dermal and inhalatory toxicity of PVH resin is studied in white rats. It is established that in acute treatment, irrespective of the route of PVC resin penetration into the organism, its effect proves weakly toxic. During chronic oral and inhalatory experiments, a slight affection of peripheral blood elements only is noted. In the lungs of the animals inhalating 2 and 6 mg/m3 concentrations for a duration of four months, no changes are detected which might be interpreted as being PVH specific. Cumulative effect, and skin stimulating and sensibilizing action of the polymer are neither established. Against the background of the obtained results, a provisional normal MAC value is proposed, namely 2 mg/m3 of PVH dust in the air of the working environment.