PubMed Health⌕ Search

Biomedical subjects

E Petrova

Publications and source records attributed to E Petrova.

13 recordsLinked to original sources
PubMed2004

Flow cytometric determination of neutrophil respiratory burst activity in workers exposed to formaldehyde.

AIM: The aim of the study was to investigate neutrophil respiratory burst activity (NRBA) in workers who were occupationally exposed to formaldehyde. METHODS: NRBA, spontaneous and stimulated with E. coli, N-formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol 12-myristate 13-acetate (PMA), was studied by means of quantitative flow cytometric determination in 29 workers who were occupationally exposed to formaldehyde; 21 healthy subjects, not exposed to formaldehyde, served as controls. All subjects underwent clinical assessment, including a review of a summary of their medical history and a physical examination. Routine haematological tests were performed. RESULTS: A statistically significant predominance of subjective symptoms and objective clinical findings of chronic upper respiratory tract inflammation, as well as decreased resistance to infections, was observed in the 29 workers exposed to formaldehyde, compared with the controls (chi2 = 9.28, P = 0.02). No statistically significant difference in the spontaneous and stimulated NRBA between the exposed workers and the control group was observed. The spontaneous NRBA (percentage oxidizing cells) was significantly lower in the group of exposed workers with upper respiratory tract findings and frequent and long-lasting infectious inflammatory relapses (median and range 0.45 (0.02-2.03), mean values 0.65 +/- 0.74) than in the healthy controls (median and range 1.35 (0.07-8.69), mean values 2.42 +/- 2.47; P < 0.05), and in the group of exposed workers with rare and short, acute, inflammation of the upper respiratory tract or without any inflammations (median and range 1.00 (0.02-8.67), mean values 1.67 +/- 2.08; P < 0.05). A significant negative correlation between the duration of occupational exposure to formaldehyde and erythrocyte count and haematocrit was found. CONCLUSIONS: The observed decrease of spontaneous NRBA in workers with a history and clinical findings of frequent and long-lasting relapses of chronic inflammation of the upper respiratory tract could be due to formaldehyde exposure and individual susceptibility. The results obtained suggest that functional changes in polymorphonuclear neutrophil granulocytes could serve as an early indicator of an impact of formaldehyde on NRBA. The applied method might be used for identifying groups at increased toxicological risk.

Adult↗
PubMed2002

A comparative thermodynamic study for both natural and artificial RNA/DNA-protein binary complexes.

In recent years, Systematic Evolution of Ligands by EXponential enrichment (SELEX) technique has been developed into a fast growing field. In contrast to traditional recognition elements, like antibody, our interests focus on novel molecular recognition elements based on nucleic acids, which are of value both for the therapy and biosensors. A comparative study of thermodynamic for both natural and artificial RNA/DNA-protein complexes would establish bases for a specificity of complex formation. In particular, we have shown that aptamers could be used for a direct measuring of thrombin enzymatic activity in a solution.

Amino Acid Sequence↗
PubMed1995

Human hybridomas secreting monoclonal antitreponemal antibodies raised after in vitro stimulation of human lymphocytes.

Peripheral blood lymphocytes from patients with syphilis were stimulated in vitro against Treponema pallidum extract and consequently were fused with mouse myeloma cells to raise heterohybridomas secreting specific human antibodies. In these experiments, 5 heterohybridomas were selected which were shown to secrete monoclonal antibodies which recognized treponemal antigens. Some of the monoclonal (Mab 1C12, Mab 1D11) react with antigens specific to T. pallidum while others (Mab 2A2, Mab 2C8, Mab 2C11) bind to treponemal components which demonstrated group specificity.

Animals↗
PubMed1995

The diagnostic value of conventional X-ray examination of the lungs in comparison with high-resolution computed tomography (HRCT), isotope perfusion scintigraphy and the diffusion capacity in patients with pneumoconiosis.

A precise diagnosis of initial reticular forms of pneumoconioses is very difficult. The present study focuses on 30 patients with initial reticular forms of silicosis, asbestos induced interstitial lung fibrosis, mixed dust pneumoconioses and pneumoconioses of electrowelders. The anterior-posterior chest radiography (according to the ILO International Radiological Classification of Pneumoconioses, 1980), high-resolution computed tomography (HRCT), perfusion scintigraphy with 99mTc and the changes in the diffusion capacity were compared. The diagnostic value of these methods was assessed. The study continues by expanding the groups of patients examined and by including the membrane component of diffusion.

Adult↗
PubMed1994

Pneumoconioses in Bulgaria--prevalence, development, prognosis and prevention.

Prevalence of the basis types of pneumoconioses (silicosis, silicotuberculosis, asbestosis) in Bulgaria was studied during a 7-year period (1985-1991). Information was taken from reports of the Department for silicosis and other pneumoconioses control in the country. As a basis of the investigation serves the total number of workers endangered by dust exposure in different risk branches. The more rarely encountered pneumoconioses are referred to in absolute numbers. Trends in the development and prognosis of the most frequently encountered pneumoconiosis in Bulgaria could be followed. Recommendations are given for future preventive activity.

Asbestosis↗
PubMed1992

[Occupational hygiene in industrial assembly work].

Data on occupational hygienic characteristics of industrial-assembly work are reported, which have not been subject upto now to such studies. Complex hygienic evaluation of the basic physical and chemical factors of the working environment is performed as well as physiological and ergonomic characteristics of the principle professional groups, analysis of the occupational diseases and diseases with temporary disability and clinic and laboratory examinations on the workers. The following peculiarities of occupational hygienic aspect are established: 1. dynamic and multiform professional itinerary of the industrial-installing workers; 2. large variability in the characteristics of the physical and chemical factors of the working environment, most frequently surpassing the admissible norms and requirements, as well as the duration of exposure to them; 3. considerable working engagement (from 63 to 78% operation time), connected with heavy physical loading (dynamic and static), exceptionally unfavourable, compulsory and fixed working posture, possibilities of prolonged working day, high rate of involvement of the psychomotor sphere, analyzers and attention, great professional responsibility and nervous and emotional stress; 4. occupational and general morbidity of workers, adequate to the already established by the authors occupational noxa--acute poisoning with smoking gases, injury of the hearing, diseases as a result of overpressure of the locomotor apparatus and the nervous system.

Bulgaria↗
PubMed1990

[Hemostatic disorders in patients with Schoenlein-Henoch syndrome].

Several indices of coagulation and fibrinolysis were studied in 54 patients suffering from Schönlein-Henoch disease. A significant prolongation of platelet aggregation was found in parallel with a decrease of AT III and plasminogen and an increase of the fibrin monomer complexes. Consequent to heparin treatment controlled by measurements of residual thrombin activity, the indices showed a trend towards normalization. The dynamic monitoring of the above indices can be used for an overall assessment of the heparin treatment.

Adult↗
PubMed1987

[Characteristics of work capacity of patients with silicosis occurring after stopping their work in exposure to dust].

The whole contingent of patients, ill with silicosis manifested after interrupting work with dust, registered up to 1984, at the Clinic of Occupational Diseases, Sofia was examined. Analysis was made of the lasting disability of the patients. A study was performed on the relation between group of invalidity and age groups in the newly discovered cases; group of invalidity and length of service at dry drilling; group and diagnosis of the illness in stages; connection between x-ray morphological displays and functional disturbances and group of invalidity. Recommendations are given concerning the basic pneumoconiosis process and its complications and the interrelations between pneumoconiosis disease, chronic bronchitis and pulmonary emphysema.

Adult↗
PubMed1975

[Trace element and heavy metal content in the basic types of Bulgarian flour].

The content of total ashes, copper, manganese, zinc, molybdenum, lead and cadmium is investigated in the three basic Bulgarian flour brands--type 500, type 700 and type 1150. It is found out that the content of all the microelements under study shows an increase from white (type 500) to darker flour (type 1150). Zinc and manganese content is the highest in all three types of flour investigated, while cadmium content is the lowest. No essential difference is established in the individual microelements' content of the flour from various regions of the country, except for the higher content of molybdenum, found in the flour obtained from the Plovdiv mills.

Bulgaria↗
PubMed1975

[Changes in renal ultrastructure in acute poisoning with anticholinesterase substances (an experimental study)].

The authors present findings of their experimental study of effects produced by anticholinesterase substances of the type of pinochelin ether of methylfluoride-phosphoric acid (PEMA) on the ultrastructure of the kidney. The changes manifested themselves in vacuolization of podicytes and destruction of mitochondria of the tubules' epithelium, which was accompanied by an elevation in the activity of lysosomes.

Acute Disease↗