[Some factors influencing the efficiency of disk-diffusion test to determine the antibiotic sensitivity of microorganisms].

On diffusion of an antibiotic from the disk to the nutrient medium, gel concentration of an antibiotic changes. This process is individual for each antibiotic. The action of different concentrations of the antibiotic at different intervals results in the suppression of microbial growth around the disk (formation of a zone). The relationship between the antibiotic concentration in the disk and the diameter of a microbial growth suppression area is proportional in the limited range of concentrations. The relationship between the concentration of an antibiotic and the diameter of a growth suppression area may greatly vary for various taxonomic groups of microorganisms and for various strains. The established fact may be responsible for the disagreement of results of a microbial antibiotic sensitivity test, by using different methods and makes the standardization of the disk-diffusion test difficult.

[Radiologic diagnosis of Payr disease in children]. / Rentgenodiagnostika bolezni Paira u detei.

The experience with diagnosis of Payr disease in 119 children with the use of a roentgenologic method, in particular, irrigoscopy was summarized. Falling of the right colic flexure with formation of abrupt kinks of the transverse colon, and retention of contrast substance in the right portion of the large intestine are the main roentgenologic signs of the Payr disease.

[Characteristics of antibiotic use in children]. / Usobennosti primeneniia antibiotikov u detei.

In antibiotic therapy of children bacteriological findings should be considered. The choice of antibiotic doses depends on the drug pharmacokinetics and damaging effect, the state of the excretory organs and some other factors. Antibiotic elimination in children during the postnatal period is limited: there is a relationship between the gestation term and intensity of drug elimination. Antibiotics penetrate through the placental barrier. They are detected in the mother milk. The damaging effect of antibiotics in many respects depends on their properties, dosage and administration route. Children are more sensitive to the direct toxic action of antibiotics as compared to adults. Development of dysbacteriosis in children is frequent. Allergic reactions with diverse clinical signs are possible in children. Combined antibiotic therapy with observation of definite requirements is more efficient. Still, because of the antibiotic damaging effect monotherapy is more preferable in all possible cases.

[The effect of clonidine on humoral factors in patients with arterial hypertension]. / Vliv clonidinu na nekteré humorální faktory u nemocných s arteriální hypertenzí.

Clonidine, an agonist of central alpha-2-adrenergic receptors, reduced the peripheral sympathetic activity. With regard to the mutual pathophysiological relationship of blood pressure regulating mechanisms, the authors wanted to find out whether after clonidine administration, in addition to the known suppression of catecholamine levels (CA), also changes in the concentration of other pressor and depressor humoral substances will occur. They investigated therefore in 15 patients with essential hypertension (EH) and in three patients with pheochromocytoma the urinary excretion of free noradrenaline (NA), adrenaline (A) and dopamine (DA), the plasma renin activity (PRA), the aldosterone concentration (PAC) and atrial natriuretic factor (ANF) in plasma, using radioimmunoanalysis, always before and 24 hours after clonidine administration (Haemiton retardR) by the oral route. Its administration led in patients with EH to a decline of NA and DA. On the other hand, in pheochromocytoma their urinary excretion did not change in an unequivocal way, and when it declined, never normal NA and DA levels were reached. A excretion remained unaltered in both groups of patients. The drop of PRA after clonidine as a result of the drop of peripheral adrenergic activity was not associated with an expected parallel drop of PAC but by its rise. This effect can be explained by a reduction of the tonic inhibition of PAC output when the DA level declines. The rise of ANF after clonidine administration will be the subject of subsequent investigations. It cannot be ruled out that this effect is due to the direct action of clonidine on alpha receptors in the heart.(ABSTRACT TRUNCATED AT 250 WORDS)

[Enhanced ovarian sensitivity to gonadotropins in anestrus in sheep]. / Povyshenie chuvstvitel'nosti iaichnikov k gonadotropinam v anéstruse u ovets.

Superovulatory doses of PMSG and hCG, injected to anestrus crossbred ewes, induced more intensive luteinization of large follicles and progesterone secretion in ewes, lambed by twins (9) at first pregnancy, then in the cases of singleton lambed ewes or nonlambing ones (12). The ovaries of 2 ewes, lambed by twins, have healthy follicles, with increased estradiol concentration in their follicular fluid despite the presence of ovulatory follicles, giving corpora lutea. It is concluded that enhanced ovarian reactivity at anestrus can be related to the reserves of the reproductive system in more prolific ewes.

[Effect of various microorganisms on the activity of levorin]. / Vliianie nekotorykh mikroorganizmov na aktivnos't levorina.

Levorin added to nutrient media with growing cultures of aerobic gram-positive bacilli, Escherichia, enterococci and filamentous fungi was partially inactivated. The antibiotic activity decrease depended on the strain characteristics, incubation period and temperature. Fermentation broth filtrates of the experimental strains also inactivated levorin while to a lesser extent than the growing organisms. In contaminated levorin pastes, the antibiotic activity was lower. The fermentative nature of inactivation was not proved.

[Chemotherapy of bacteroides infection under clinical and experimental conditions]. / Khimioterapiia bakteroidnykh infektsii v klinike i eksperimente.

Bacteroides were detected in pus and bioptates of the majority of 125 patients with purulent and purulent septic infections of various localization. In 90 per cent of the subjects the bacteroides were detected in association with aerobes, facultative and obligate anaerobic bacteria. The species of the bacteroides and concomitant microflora isolated from the cases with different diseases were defined by endogenic sources of the microbial contamination. Sensitivity of 112 bacteroide strains to antimicrobial agents was tested. Chloramphenicol, clindamycin, metronidazole, cefotaxime and heliomycin proved to be the most efficient. Efficacy of heliomycin was detected in hamsters with experimental bacteroide infection in the buccal sac. Thorough bacteriological examination is required for rational chemotherapy of bacteroide infections.

[Rapid determination of microbial sensitivity to antibiotics by using laser spectroscopy]. / Uskorennoe opredelenie chuvstvite'lnosti mikroorganizmov k antibiotikam s ispo'lzovaniem lazernoi spektroskopii.

A method of express-determination of the susceptibility of microbes to antibiotics is presented based upon the registration by the method of laser spectroscopy of changes of optic properties of cultures at early terms of their incubation in liquid nutrient media with addition of antibiotics. The method was elaborated in 13 standard strains of Staphylococcus aureus and Escherichia coli with antibiotics of different classes, tested on the microflora of pus of patients with sepsis, verified by the method of serial dilutions of the antibiotic. The method makes it possible to obtain the minimum inhibiting concentration of antimicrobial preparations 1 h after the moment of obtaining the native material.

[Effect of captopril on arterial pressure, systemic hemodynamics and renin activity in the blood plasma of rats with spontaneous hypertension]. / Vliianie kaptoprila na arterial'noe davlenie, sistemnuiu gemodinamiku i aktivnost' renina v plazme krovi krys so spontannoi gipertenziei.

An angiotensin-I-converting enzyme, captopril, was administered since birth onward to normotensive (NR) and spontaneously hypertensive rats (SHR). It produced a marked hypotensive effect in SHR only. Cardiac output and circulating blood volume were similar in intact and experimental animals, NR and SHR alike. Captopril considerably increased plasma renin activity in NR and SHR.

[Use of different nutrient medium variants in determining the antimicrobial activity of neomycin]. / Ispol'zovanie razlichnykh variantov pitatel'nykh sred pri opredelenii antimikrobnoi aktivnosti neomitsina.

Gel diffusion regularities with respect to neomycin sulfate substances differing in their composition and the antibiotic separate components were studied on nutrient media of diverse composition. Optimal conditions for standardization of neomycin sulfate antimicrobial activity with using the agar diffusion method and synthetic medium are determined.

[Microcomputer-based automation of the microbiological analysis of antibiotic activity]. / Avtomatizatsiia mikrobiologicheskogo analiza aktivnosti antibiotikov na baze mikroEVM.

Laboratory informative computer systems (LICS-10 and LICS-11) for microbiological assay of antibiotics were developed. The systems are based on the ISKRA-1256 computer. As compared to the routine method with the use of the well-known V. S. Dmitrieva's Tables the LICSs provide more than a 2-fold decrease in the working hours of the assay. The data on the specific software for the LICSs are presented and the algorithms for the calculations are described.