[The new facultatively chemolithoautotrophic, moderately halophilic, sulfate-reducing bacterium Desulfovermiculus halophilus gen. nov., sp. nov., isolated from an oil field].

The new mesophilic, chemolithoautotrophic, moderately halophilic, sulfate-reducing bacterium strain 11-6 could grow at a NaCl concentration in the medium of 30-230 g/l, with an optimum at 80-100 g/l. Cells were vibrios motile at the early stages of growth. Lactate, pyruvate, malate, fumarate, succinate, propionate, butyrate, crotonate, ethanol, alanine, formate, and H2 + CO2 were used in sulfate reduction. Butyrate was degraded completely, without acetate accumulation. In butyrate-grown cells, a high activity of CO dehydrogenase was detected. Additional growth factors were not required. Autotrophic growth occurred, in the presence of sulfate, on H2 + CO2 or formate without other electron donors. Fermentation of pyruvate and fumarate was possible in the absence of sulfate. Apart from sulfate, sulfite, thiosulfate, and elemental sulfur were able to serve as electron acceptors. The optimal growth temperature was 37 degrees C; the optimum pH was 7.2. Desulfoviridin was not detected. Menaquinone MK-7 was present. The DNA G+C content was 55.2 mol %. Phylogenetically, the bacterium represented a separate branch within the cluster formed by representatives of the family Desulfohalobiaceae in the subclass Deltaproteobacteria. The bacterium was assigned to a new genus and species, Desulfovermiculus halophilus gen. nov., sp. nov. The type strain is 11-6T (= VKM B-2364), isolated from the highly mineralized formation water of an oil field.

[Description of Desulfotomaculum nigrificans subsp. salinus as a new species, Desulfotomaculum salinum sp. nov].

This study focused on the physiological, chemotaxonomic, and genotypic characteristics of two thermophilic spore-forming sulfate-reducing bacterial strains, 435T and 781, of which the former has previously been assigned to the subspecies Desulfotomaculum nigrificans subsp. salinus. Both strains reduced sulfate with the resulting production of H2S on media supplemented with H2 + CO2, formate, lactate, pyruvate, malate, fumarate, succinate, methanol, ethanol, propanol, butanol, butyrate, valerate, or palmitate. Lactate oxidation resulted in acetate accumulation; butyrate was oxidized completely, with acetate as an intermediate product. Growth on acetate was slow and weak. Sulfate, sulfite, thiosulfate, and elemental sulfur, but not nitrate, served as electron acceptors for growth with lactate. The bacteria performed dismutation of thiosulfate to sulfate and hydrogen sulfide. In the absence of sulfate, pyruvate but not lactate was fermented. Cytochromes of b and c types were present. The temperature and pH optima for both strains were 60-65 degrees C and pH 7.0. Bacteria grew at 0 to 4.5-6.0% NaCl in the medium, with the optimum being at 0.5-1.0%. Phylogenetic analysis based on a comparison of incomplete 16S rRNA sequences revealed that both strains belonged to the C cluster of the genus Desulfotomaculum, exhibiting 95.5-98.3% homology with the previously described species. The level of DNA-DNA hybridization of strains 435T and 781 with each other was 97%, while that with closely related species D. kuznetsovii 17T was 51-52%. Based on the phenotypic and genotypic properties of strains 435T and 781, it is suggested that they be assigned to a new species: Desulfotomaculum salinum sp. nov., comb. nov. (type strain 435T = VKM B 1492T).

[Immunological effects of captopril and ramipril in patients with hypertension]. / Immunologicheskii éffekt kaptoprila i ramiprila u bol'nykh gipertonicheskoi bolezn'iu.

Fifteen patients with essential hypertension underwent treatment with captopril (7 patients) and ramipril (8 patients). The drugs belong to angiotensin-converting enzyme (ACE) inhibitors. Pretreatment immunological examination and that after a 10-15-week course of the above therapy involved measurements of IgG, IgA, IgE and beta 2-microglobulin. The analysis of the trend in the immunological indices demonstrated that captopril, distinct from ramipril by the presence of a sulfhydryl group, caused a decrease in immunological parameters suggesting a potential role of culfhydryl groups in mediating ACE inhibitor action on the immune system. The immunological properties of captopril may appear useful in various systemic diseases.

[Hypotensive and hemodynamic effects of guanfacine in arterial hypertension]. / Gipotenzivnyi i gemodinamicheskie effekty guanfatsina pri arterial'noi gipertonii.

The therapeutic efficacy of guanfacine was investigated in a group of 32 hypertensive patients. Guanfacine caused a marked decrease in total peripheral vascular resistance (by 19.8%, p less than 0.001) and, hence, in blood pressure (by 19.4%), p less than 0.001). A slight reduction in the heart rate (by 9.8%, p less than 0.01) was compensated by an increase in stroke volume (by 11.8%, p less than 0.05) so that cardiac output remained constant or was even slightly raised. After 4 weeks of treatment there was a regression of the left ventricular wall thickness and mass (by 7.43 +/- 2.44 g, p less than 0.05). Guanfacine monotherapy was effective in 75% of patients with moderate hypertension (using low doses 1-3 mg/day). In severe hypertensive disease a satisfactory therapeutic response was mostly achieved by a combination of Guanfacine (3-5 mg/day) with a beta-blocker, diuretic or vasodilator. Guanfacine is a promising agent in the long-term treatment of stable hypertension, particularly in patients, whom diuretics or beta-blockers are contraindicated.

[Therapeutic value of pratsiol and its effect on indicators of central and peripheral hemodynamics in patients with hypertension]. / Lechebnyi effekt pratsiola i ego vliianie na pokazateli tsentral'noi i perifericheskoi gemodinamiki u bol'nykh gipertonicheskoi bolezn'iu.

Thirty-eight patients with stage IIB essential hypertension have been studied to determine the therapeutic activity of prazosine (pratsiol, "Orion" company, Finland) and its influence on the parameters of the central and peripheral hemodynamics. It has been established that following the oral administration of the drug, a hypotensive effect develops in 90-120 min and lasts for about six h. After a three-week course of treatment, the arterial pressure in the majority of patients decreased due to a reduction in the total peripheral resistance and the tone of the resistant vessels (arterioles). Simultaneously, there was an increase in the heart rate, end diastolic and stroke volumes and in the cardiac output. In a smaller portion of patients, the arterial pressure decreased due to the predominant reduction in the venous tone; the elasticity of the veins increased sharply, the end diastolic stroke and minute volumes diminished. The heart rate and total peripheral resistance showed no statistically significant changes. It has been established that pratsiol acts as an arterial and venous vasodilator and that it is advisable to use the drug in combination with beta-blockers and diuretics.

[Therapeutic effect of trandat, an alpha- and beta-adrenergic receptor blockader, and its effect on central, regional and intracardiac hemodynamics]. / Lechebnyi éffekt trandata-blokatora al'fa- i beta-adrenergicheskikh retseptorov i ego vliianie na tsentral'nuiu, regionarnuiu i vnutriserdechnuiu gemodinamiku.

A study of the effect of labetalol (trandat) was carried out in 75 arterial hypertensive patients. The central, regional, and intracardial hemodynamics were studied in 40 of them by echocardiography and rheography. A 25% decrease in BP and subjective improvement were observed on the 1-2 week of treatment. Total peripheral vascular resistance decreased by 22.4%, heart rate - 7%, intramyocardial tension - 21%, left ventricular wall thickness and myocardial mass - 2.5%; brain and crural vascular tone also decreased. Cardiac index, ejection fraction, and left ventricular circumferential shortening velocity were not changed. In fourteen patients there was observed a significant decrease in the plasma renin activity. A number of advantages of trandat effect was found as compared to the effect of propranolol: blood pressure decreased at the account of the total peripheral vascular resistance diminution without suppression of myocardial contractility; the regional blood circulation was improved.

[Use of Visken-15 for treating hypertension]. / Primenenie Viskena-15 dlia lecheniia bol'nykh gipertonicheskoi bolezn'iu.

The hypotensive effect of visken-15, a blocking agent of the beta-adrenergic receptors, was studied in 7 patients with stage IB hypertensive disease, in 18 with stage IIA, and in 8 patients with stage IIB under conditions of in- and out-patient establishments. A favourable effect was produced in 81.5% of patients who were given one tablet of the drug once or twice a day. Treatment with visken-15 led to a decrease in systolic, diastolic and mean arterial pressure, in the rate of cardiac contractions, and in the blood minute volume at rest, in the orthostatic position, and during physical load. Visken-15 is marked by low toxicity, it is tolerated well and seldom causes side effects. The drug is recommended for the treatment of patients with early stages of hypertensive disease.