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Biomedical subjects

B Todorov

Publications and source records attributed to B Todorov.

At least 19 recordsLinked to original sources
PubMed2005

On the influence of soil properties on the transfer of 137Cs from two soils (Chromic Luvisol and Eutric Fluvisol) to wheat and cabbage.

Two types of soils (Eutric Fluvisol and Chromic Luvisol) and two crops (wheat and cabbage) were investigated for determination of the transfer of 137Cs from soil to plant. Measurements were performed using gamma-spectrometry. Results for the soil characteristics, transfer factors of the radionuclides (TF), and conversion factors (CF) (cabbage/wheat) were obtained. The transfer of 137Cs was higher for Chromic Luvisol for both the plants. Statistically significant dependence of TF of 137Cs on its concentration in soil was established for cabbage. Dependence between K content in the soil and the transfer factor of 137Cs was not found due to the high concentrations of available K. Use of bioconcentration factor (BCF) (ratio between the activity concentration of a radionuclide in a reference plant to its concentration in another plant) is demonstrated and proposed for risk assessment studies.

Brassica↗
PubMed1990

[The therapeutic effect of nitromint retard on patients with stable angina pectoris].

The antianginal [correction of antidiagnose] efficacy of nitromint retard was studied in 62 middle aged patients with angina pectoris in a 4 week treatment with a 24 h dose of 2.6 mg. Bicycle ergometry [correction of A veloergometria] was conducted before the treatment and at the end of the fourth week. The average number of anginal attacks decreased from 4.0 +/- 1.9 to 1.6 +/- 1.3 during the first week and to 0.0 +/- 0.7 at the end of the 3rd week. The average threshold power increased at the end of the 4th week. Nitromint retard increased considerably the tolerance to physical load and did not increase the consumption of oxygen. The desired effect was achieved in 66.13% of the patients.

Angina Pectoris↗
PubMed1987

[Mechanisms of the lactogenic action of thyroid hormones and nonspecific resistance in ruminants].

Studied was the effect of thyroid hormones on the nonspecific resistance and the milk productivity of ruminant animals in the conditions of hypodynamia and in various functional conditions of the thyroid gland. Both the removal of the thyroid gland (thyroidectomy) and the hypofunction of the gland (as induced by ammonium perchlorate at 10 mg/kg body mass) were accompanied by the drop of the indices characterizing the nonspecific resistance of the animals as well as their milk productivity. The immobilization of lactating ruminant animals (hypodynamia) had a negative impact on the milk producing process, enhanced the incretion of ACTH, lowered the release of thyroid hormones (T3, T4, FT4) and decreased milk productivity, deteriorating the biologic properties of colostrum. The thyroid gland and its hormones (T4, T3) were shown to have a positive effect on milk secretion, raising the activity of the enzyme adenylate cyclase and the amount of the cyclic 3.5 cyclic adenosine monophosphate (cAMP) in the parenchymal tissue of the mammary gland.

Animals↗
PubMed1987

[Total LDH activity and isoenzyme spectrum in experimental Cysticercus ovis infestation of lambs and kids].

Investigations were carried out with 10 lambs and 4 kids at the age of two months, divided into three groups. The test animals of the first group (5 lambs) were infected with 7,000 T. ovis eggs each, and those of the second group (5 lambs) and those of the third group (4 kids)--with 20,000 T. ovis eggs each. It was found that following infection the total activity of lactate dehydrogenase (LDH) rose, reaching its peak values on the 12th and 15th day. On the 12th day the strongly enhanced enzyme activity was due to the rise of LDH1, while on the 15th day the enhancement was associated with the rise of LDH5 that was characteristic of the skeletal muscles. In the period of forming the connective tissue capsule around the cysticerci the changes in the total activity and the isoenzyme spectrum were more slightly manifested. After the 30th day both the activity and the spectrum of LDH steadily came back to normal. With a C. ovis infection there was also a strongly expressed response on the part of hemopoietic organs, with a pronounced LDH3 activity.

Animals↗
PubMed1987

[Effect of a chromatographically purified bile secretion on the blood protein levels in hens].

The injection of chromatographically purified biliary fraction from broiler birds, rich in bile acids, led to a dependable drop of serum proteins in chickens. Treatment of the latter with a bile sample from swine, obtained in a similar way (the reaction for bile acids being negative) did not lead to essential changes in the content of plasma colloids. Results showed that bile acids were of definite importance as regards the blood level of proteins and the redistribution of proteins in the body with the individual species of animals.

Animals↗
PubMed1985

[Biochemical and ultrastructural changes in the liver of rats with a severe form of acute radiation sickness].

Biochemical and ultrastructural studies were carried out on the liver of male rats with a severe form of acute radiation disease. The animals were treated only once with a total dose of 6.7 Gy by means of a gamma-unit Rokus at the rate of 0.9 Gy per min. It was found that with the acute and severe form of radiation disease thus produced the activity of liver enzymes with cytoplasmic localization such as SDG, GPT, and GOT strongly rose in the blood plasma over the first 24 hours following treatment. The activity of ChE as an enzyme that was specific of the endoplasmic reticulum also rose. The normal ultrastructure of hepatocytes was unaffected over the first 24 hours after irradiation. Within the period of the clinical manifestation of the disease, however, there set in strongly expressed destructive changes in the mitochondria (from the eighth to the fifteenth day). It was concluded that the changes in the liver that were characteristic of the severe form of radiation disease set in early.

Acute Disease↗
PubMed1983

[Experimental mastitis in cows caused by Staphylococci, Streptococci and Corynebacteria].

Mastitis was experimentally induced in seven cows of the Black-and-white breed through the intramammary or i/v application of bacterial cultures of the encapsulated variant of Staph. epidermidis as well as of Str. agalactiae and Cor. pyogenes. The disease ran a course with high body temperature, strongly manifested inflammatory changes in the mammary gland, and altered phagocytic activity. It was found that the introduction into the mammary gland of a 'stable-specific' bovine blood serum in combination with the preparation nitrofuridine (a Shiff base of the 5-nitrofurfurol with sulfaguanidine) which boosts the phagocytic activity, had produced a therapeutic effect.

Animals↗
PubMed1983

[Leukocyte enzyme activity in the gamma-ray irradiation of lambs].

Investigated was the activity of lactatedehydrogenase (LDH) and alkaline phosphatase (AP) of leukocytes obtained by means of urographic gradient in the clinical course of acute radiation sickness of small ruminants. The lambs were irradiated with 3.2 Gy (320 rad). It was found that the activity of AP and LDH rose in the first 20 hours following treatment, the processes of aerobic glycolysis becoming more intense in the leukocytes. The study on the activity of AP and LDH in the leukocytes could be used as an adjunct along with the use of the hematologic indices in the determination of the severity of the disease.

Acute Disease↗
PubMed1983

[Enzyme activity in the blood plasma of lambs with acute radiation sickness].

The activity was determined of sorbitol-dehydrogenase (SDH), cholinesterase (CE), leucine-aminopeptidase (LAP), acid phosphatase (AP), and glutamate-dehydrogenase (GDH) in blood plasma of lambs irradiated with 200, 320, and 450 Rad. Results showed that with the mild form of acute radiation sickness (treatment with 200 Rad) the activity of the blood enzymes did not change. With the severe (320 Rad) and the peracute (450 Rad) forms of the disease within the first 24 hours the activity of SDH and CE rose 3 to 5 times, and that of GDH and AP--twice within a period of 1 to 3 days following irradiation. In the case of a threefold increased activity of SDH and CE within 15 to 24 hours of treatment the diseased animals died. Parallel hematologic investigations revealed that well manifested leukopenia with these two forms of the sickness took place after the 24th hour. Activity determination of the investigated plasma enzymes within the first 15-24 hours following irradiation could be used as an adjunct test to the study of the hematologic indices for the early diagnosis of the severe and peracute forms of irradiation sickness as well as for the exit of the disease.

Acute Disease↗
PubMed1982

[Aspects of the large divergence in the sialic acid level of the blood serum of poultry].

Scanning electron microscopy made it possible to establish that there were no echocytic forms of the erythrocytes in chickens in which the blood serum level of sialic acid was below 35 and over 60 mg%. The amount of the total protein and the individual protein fractions did not correlate with the level of sialic acid. On the other hand, the high level of sialic acid could be accompanied by both low and high blood sugar content. Contrary to mammals the blood serum level of sialic acid in chickens was found to vary within a wide range. This could be explained by the amount and composition of the gall secretion which had an impact on the aging of erythrocytes and the enzyme activity of their membrane. Stated is the part played by the occasional mechanism in the 'decialization' process with regard to glucoproteins in vivo and the opinion is set forth that the mechanism of triggering the proteolytic activity of the membrane of aging erythrocytes could be associated with certain components of the bile.

Animals↗
PubMed1978

[Morphological changes in the liver of gamma-irradiated chick embryos and chickens].

The morphologic changes produced in the liver through irradiation at the rate of 1000 rad are characterized chiefly by a well expressed fatty dystrophia. At many sites there are pycnotic and lysed nuclei of the parenchymal cells. In the embryonic liver these changes are most strongly manifested in 12-day-old embryos. In contrast to the irradiated adult birds the embryonic liver presents no processes on necrosis after radiation treatment.

Animals↗
PubMed1977

[ATP and ATPase activity in the liver and brain cell fractions of gamma-irradiated chick embryos and newly hatched chicks].

Studied were the level of ADP and the adenosinetriphosphatase in nuclei, mitochondria, and microsomes taken from the brain and liver of singly gamma-irradiated at 1000 rd chick embryos and birds. As a result of the treatment of ADP content dropped, while the activity ADP rose. These changes were most strongly expressed in the nuclei, then in the mitochondria, and to a lesser extent-in the microsomes. Twelve-day chick embryos showed more markedly expressed radiosensitivity than newly hatched chicks. This embryonal state is characterized by intense growth, differentiation and metabolic processes in the liver, which substantiate not only the higher radiosensitivity of this age group but the more strongly expressed changes in the liver as compared with the brain.

Adenosine Triphosphatases↗
PubMed1977

[Treatment of rheumatoid arthritis with the immunosuppresive agent, prorezid].

Prorezid treatment was applied to 30 patients with rheumatoid arthritis. It was applied per os with a daily dose of 300 mg to 12 subjects; to 18-intravenous drop infusion with 5 per cent serum glucose--daily dose 400 mg. Oral administration total dose-7-8 g; infusion-10-12 g. Drop infusion administration proved to be more effective and especially the combination of the preparation with salycilates, pirazolon derivatives, minimal doses of corticosteroids and antibiotics. Favourable effect on articular syndrome was obtained in 20 patients (66.6%) about 2-3 and sometimes 4-6 weeks after the onset of the treatment. First the articular pain was attenuated, latter on--the morning stiffness (3-4 week), the movements in the joints involved were improved, the edema decreased towards the 4-6th weeks. A complete normalization of the laboratory indices was observed in none of those patients. In 10 of the patients (33.3%) no clinical improvement was attained in the course of the treatment. In four of them--the improvement developed 4-6 months later, with a longer drug administration. Prorezid preparation is with a low toxicity, with manifestation of transitory side effects in single patients--diarrhoea, mild leukopenia. Alopecia was not observed. Those properties make the drug suitable for application in patients with rheumatoid arthritis whose treatment with the rest applied drugs failed to give results.

Adult↗
PubMed1976

[Effect of ionizing radiation on the activity of liver acid phosphatase in chick embryos and chickens].

The treatment of chick embryos and chickens at 1000 rad leads to the decrease of the total activity and the increase of the free activity of the acid phosphatase in the liver. These changes are mostly manifested at the 72nd hour following irradiation. The electron-microscopic studies reveal secondary lysozomes (cytolyzomes) full of round or elongated structures of varying density. All changes are most strongly manifested in 12-day-old embryos, and are most weakly manifested in 20-day-old ones.

Acid Phosphatase↗
PubMed1976

[Effect of stimulating doses of ionizing radiation on the stability of the liver mitochondria of chick embryos and chicks].

Treatments at the rate of 3 rad of chick embryos and young birds have led to the stabilizing of the mitochondrial structures and to lowering the access of enzymes to their substrates. The free activity of malate dehydrogenase drops. Electron microscopic studies reveal that the number of mitochondria rises following irradiation with stimulating doses (3 rad). Mitochondrial cristae remain intact and the matrix presents higher electronic density.

Age Factors↗
PubMed1975

[Changes in the liver mitochondria due to gamma-ray irradiation of hen embryos and chickens].

Studied were the changes in the activity of the mitochondria-specific enzyme malatedehydrogenase (MDH) and the ATP content in the liver of chick embryos and chickens irradiated with 1000 rad. The total activity of MDH as well as the content of ATP dropped and the 'free' activity of MDH rose, but such was not the case of 20-day-old embryos. These changes were most pronounced in 12-day-old embryos. This showed that the changes in the mitochondria depend on the stage of embryonic development.

Adenosine Triphosphate↗