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Biomedical subjects

D Todorov

Publications and source records attributed to D Todorov.

At least 37 records · Page 2Linked to original sources
PubMed1985

Synthesis and study of spin-labeled nitrosoureas.

For the first time we have synthesized spin-labeled nitrosoureas and have studied their properties--reduction of the iminoxyl group by vitamin C leading to the formation of the corresponding hydroxylamine derivatives and degradation in the presence of an aminoradical, leading to biradicals. The ESR spectra of biradicals in methanol have nine hyperfine resonance lines. The spin-labeled nitrosoureas have shown a high antitumor activity against the L 1210 lymphoid leukemia and P 388 lymphocytic leukemia in BDF1 mice. A study of a broad range of transplantable tumors is in progress.

Animals↗
PubMed1985

[Parallel morphological, enzyme and immunological research on the jejunal mucosa in patients with gluten enteropathy, chronic nonspecific enteritis and ulcerative colitis].

The results are reported from the study on 120 patients, 30 of them with gluten enteropathy, 50--with chronic unspecified enteritis and 40--with chronic ulcerous colitis. Small intestinal aspiration biopsy was performed to all patients with histomorphological, electron microscopic, enzymatic and immune-fluorescent study. The secretory immunoglobulins in the jejunal juice were studied in 40 patients. Morphological changes, various degrees, were established, that correlate with the increased number of IgG and IgM secretory cells. The exclusion of gluten from the diet in case of gluten enteropathy was followed by normalization of the number and percentage ratio of IgSC and of secretory immunoglobulins. The enzymatic and immune disorders, in chronic unspecific enteritis correlate with the electron microscopic and precede the histologic ones. The role of immune system of small intestine in the etiology and pathogenesis of the various intestinal diseases is discussed.

Adult↗
PubMed1985

[Mycoplasma carrier state in the respiratory apparatus of sheep and lambs].

Mycoplasma and acholeplasma organisms (M. ovipneumoniae, M. arginini, etc.) were isolated from clinically normal lambs and sheep as well as from lambs with a respiratory disease. M. ovipneumoniae was more frequently isolated than M. arginini, and was found in higher percent during the winter. Both sheep and lambs of the Romanovska breed proved more susceptible, however, lambs of local breeds, aged 30-40 days also contracted the disease in conditions of overpopulation and higher humidity. The respiratory diseases were complicated with P. haemolytica infections.

Animals↗
PubMed1984

[Acute basophilic leukemia in a 75-year-old man. A clinical and cytological study with a review of the literature].

The authors present a rare clinical case of cytomorphologically and cytochemically confirmed acute basophil leukosis ( ABL ) in a male, aged 75. A comprehensive review of the present-day literature on the problem is made with detailed discussions of the differential diagnostic criteria upon which the diagnosis is made. The discussion emphasized some aspects of the cytomorphological characteristic, not finally solved, and on the nozological belonging of ABL .

Acute Disease↗
PubMed1984

[Correlation between immunoglobulin-secreting cells and secretory immunoglobulins in the small intestine in chronic intestinal diseases].

A total of 45 patients were studied: seven with gluten enteropathy and 38 with chronic unspecific enteritis. Histological and immunefluorescent studies were performed and to a part of the cases--enzymatic and electron-microscopic investigations of the jejunal mucosa. An increased number of immuneglobulin -secreting cells was established in the non-treated patients with gluten enteropathy, growing with age. In the cases with chronic unspecific enteritis with a manifested clinic, a tendency to decrease of the number of IgSC was observed, with growing percentage of IgG-SC and the values of the secretory IgG. There was no correlation between the intraepithelially located lymphocytes and those in the chorion, as well as between the duration of the disease, number and percentage distribution of Ig-SC.

Antibody-Producing Cells↗
PubMed1981

[Cases of clinical and subclinical mastitis due to "D" streptococci].

Cytologic and bacteriologic investigations were carried out with a total of 364 samples of cow milk and secretion from 11 farms taken from individual quarters of the udder that have reacted positively and strongly positively with the rapid mastitis test Bernburg. It was found that in 330 of the cases there were data of clinical and subclinical mastitis of varying etiology. In 43 of the cases the causative agent (as isolated in pure cultures) proved to be "D" streptococci, giving positive reaction as judged by Schermann's criteria--from 9 cases of clinical and 34 cases of subclinical mastitis. The cell count varied from 360 000 to more than 5 million per cub. cm. Detailed studies were carried out on the cultural and biochemical properties of 31 strains of "D" streptococci, 17 strains belonging to Str. faecalis var. zymogenes, 9 strains--to Str. faecalis var. faecalis, and 5 strains--to Str. faecalis var. liquefaciens.

Animals↗
PubMed1981

Influence of antitumor drugs of natural origin on the intramuscular and subcutaneous form of five transplantable tumor models.

The influence of six antitumor drugs of natural origin (rubomycin, bruneomycin, olivomycin, mitomycin C, vinblastine, and vincristine) on five transplantable tumor models (sarcoma 37, sarcoma 180, Ehrlich tumor, RL-67 and TAVS) was investigated. Each tumor was transplanted subcutaneously and intramuscularly, bilaterally, on one animal. Marked differences in the sensitivity between subcutaneous and intramuscular form of Ehrlich tumor and more slightly of TAVS were established. The used experimental regimen held out possibilities for saving labor, animals and substances as well as for the study of potential antitumor substances of natural origin at maximum equalized biological conditions.

Animals↗
PubMed1981

[Etiological study of mastitis in cows].

The rapid mastitis test was employed to study a total of 13 880 cows on 40 farms. Positive for mastitis proved 2384 udder quarters. Clinically manifested mastitis was established in 3.23 per cent of the cases, subclinical mastitis - in 58.14 per cent, carrier status - in 12.55 per cent, secretion disturbances - in 22.58 per cent, and normal proved 3.84 per cent. In the mastitis-positive cases pathogenic streptococci were isolated in 57.14 per cent of the quarters, staphylococci - in 20.77 per cent, Corynebacteria - in 9.09 per cent, and other bacteria - in 5.19 per cent. In the cases with subclinical mastitis staphylococci accounted for 40.93 per cent, streptococci - for 38.7 per cent, Corynebacteria - for 14.22 per cent, and other organisms - for 6.0 per cent. Most frequently encountered were the carriers of staphylococci - 46.8 per cent, followed by those of Corynebacteria - 26.4 per cent, and of streptococci - 20.73 per cent.

Animals↗
PubMed1980

[Cellular element study of bulk milk].

Cytologic and microbiological investigations were carried out of pooled milk arriving in two milk plants, coming from various farms in amounts of 300 to 4 000 1. Additional studies were made of milk samples taken in the barn after milking a group of 15--30 cows in amounts of 80--260 1 and samples from tanks with capacity of 6 to 10 tons stored in the milk plants. Cell content was indirectly determined by rapid mastitis tests and directly by Breed's method; cultures were made on TCT medium to establish mastitis Streprococci and most of all of Str. agalactiae. It was found that the cell content of pooled milk arriving in the milk plants is in 80.74 per cent under 400 000 and in 19.26 per cent over 400 000 cells per cc milk. Their determination in pooled milk is a reliable orientation index for evaluation of the farm's mastitis status. A norm is suggested for the cell content of pooled milk--400 000 in cc milk--which corresponds to the present yeild conditions and to those in the near future and to the real possibilities of occurence of secretion disturbances and bovine mastitis. The adoption of the norm will improve mastitis control and will raise milk quality.

Animals↗
PubMed1979

[Change in ion transport across the epithelium of the frog skin isolated from the body].

The authors carried out measurements of ionic transport through the epithelium on preparations of isolated and nonisolated skin by the method of Ussing and Zerahn (short-circuiting technique). The blood and nervous connection with the body was preserved in some of the skin preparations (nonisolated) during the experiment. For the purpose the two chambers of Ussing were modified in such a way that this connection could not be interrepted becuase of compression of blood vessels and nerves. Comparative measurements showed that isolation of the skin from the body of a frog caused significant reduction of active transport of ions through the skin epithelium. After addition of acethylcholine, eserine or dipterex to the solution of the internal or external surface of the preparation the nonisolated skins revealed statisticaly not proven tendency to greater reactivity.

Acetylcholine↗
PubMed1978

[Experiment to potentiate the effect of cyclophosphamide combined with tempidon and caffeine in leukemia L1210 and Lewis hepatic carcinoma].

The authors carried out experiments on mice DBA/2 and BDF1 with leucosis L1210 and lung carcinoma of Lewis and found that psycotropic preparations tempidone and caffeine did not manifest antitumorous effect and toxicity after the used doses and scheme of treatment. Tempidone enhanced antitumorous action of small and mean doses of cyclophosphamide in mice with leucosis L1210. In the triple combination (tempidone, caffeine and cycl phosamide) the caffeine enhanced this action of tempidone without raising toxicity in mice with leucosis L1210, but not in mice with lung carcinoma of Lewis.

Animals↗
PubMed1977

[Comparative studies of methods for the bacteriological diagnosis of mastitis in cows].

Comparative studies were carried out on some methods and nutrient media used for the isolation and identification of mastitis causative agents. Milk from normal andmastitis-affected udder quarters was aseptically sampled and treated under various conditions. Individual samples were simultaneously seeded in different media. The following conclusions were drawn: 1. Milk samples for the diagnosis of mastitis of a subclinical character can be taken at the beginning and at the end of milking. 2. Direct seedings of milk have equal diagnostic value as those of the sediment. With the former the process of bacteriologic treatment of the samples is shortened in time, and the isolation and differentiation of the mastitis agents is rendered feasible. 3. At the present etiologic structure of the subclinical types of mastitis in this country most suitable has proved the blood agar medium in which almost all mastitis causative agents can be demonstrated. 4. Kartashova's medium and the TKT-medium possess a pronounced selectivity with special reference to streptococci and have higher diagnostic value for farms where streptococcus mastitis is prevailing.

Animals↗
PubMed1977

[Sensitization to mites in house dust among children suffering bronchial asthma].

The results of studying allergy to domestic dust in 168 patients suffering from bronchial asthma are presented. The diagnosis was made by means of the domestic dust allergen (10000 PNU), fraction E extracted from the whole allergen by Berrens and Young's method, and with lyophilized extract from D. pteronussinus, farinae and Glycyphagus ticks isolated from domestic dust by Voohorst and Spieksma's method. In parallel, IgE was determined in the blood serum of the patients under study by the radio-allergo-sorbent test; IgG was also determined. Microticks proved to be not the only factor determining the activity of domestic dust. Results of diagnosis in vivo and in vitro were found to correlate. The authors believe that the activity of domestic dust allergen formed on account of the reactions of the Maillard's type, in which a significant role was played by the "lysine-sugar) compounds.

Adolescent↗
PubMed1976

[Coliform microflora of commercial Caucasian cheese].

Studied was in the course of several years the extent of coliform bacterial contamination and the peculiarities the bacteria present in ripened cow's and ewe's white brine cheese offered for consumption. It was demonstrated that these kinds of cheese released in the commercial system contain up to 3.1 per cent coliform bacteria. Certain correlation was established between the coliform count in the cheese and the degree of ripening, the consistence, and the aspect of the cross section surface. If hygiene measures were not observed cheese could be contaminated additionally with coliforms during handling in the shops. Coliform microflora was presented mainly by strains characteristic of fresh fecal contamination (E. coli) and urease-positive organisms of the Citrobacter and Enterobacter genera. To guarantee the consumption of qualitative (in terms of hygiene) white brine cheese it is necessary to include into the respective standards the index "coli titer" of a unit value.

Animals↗
PubMed1976

[Effect of acetylcholine on active ion transport across the epithelium of frog skin].

The effect of acetylcholine on isolated skin of Rana ridibunda is studied. The application of acetylcholine (1 mM) in Ringer's solution, washing the outer aspect of the skin, causes slow and smooth increase in the preparation's current and potential. Upon acetylcholine addition to the solution on the inner aspect, the increase of the above parameters runs a course along a two-peaked curve. It is presumed that in the latter case acetylcholine, prior to exert a direct effect on the epithelium, influences some of the nerve or glandular formations in the skin corium.

Acetylcholine↗