Physiological and phylogenetic characterization of a novel lithoautotrophic nitrite-oxidizing bacterium, 'Candidatus Nitrospira bockiana'.

A new isolate of a lithoautotrophic nitrite-oxidizing bacterium was obtained from internal corrosion deposits from a steel pipeline of the Moscow heating system. The organism oxidized nitrite as the sole energy source and fixed carbon dioxide as the only carbon source. The cells were extremely pleomorphic: loosely wound spirals, slightly curved and even straight rods were detected, as well as coccoid cells. The highest rate of nitrite consumption (1.5 mM nitrite as substrate) was measured at 42 degrees C, with a temperature range of 28-44 degrees C. In enrichment cultures with Nocardioides sp. as an accompanying organism, optimal oxidation of 5.8 mM nitrite occurred at 45 degrees C, with a range of 28-48 degrees C. Neither pyruvate nor yeast extract stimulated nitrification. Organotrophic growth was not observed. Phylogenetic analysis of 16S rRNA gene sequences revealed that the novel isolate represents a new sublineage of the genus Nitrospira. On the basis of physiological, chemotaxonomic and molecular characteristics, the name 'Candidatus Nitrospira bockiana' is proposed.

Large-scale experiments for microbiological evaluation of measures for safeguarding sulfidic mine waste.

In the framework of a German-Romanian scientific cooperation, experiments were performed to evaluate feasible and cheap techniques for the safe storage of mine waste to prevent acid rock drainage (ARD). A large four-chamber percolator (4CP) was installed in a waste heap at Ilba Mine, Romania, to test the effect of biocides and alkaline layers on the bacteria causing acid rock drainage (ARD). The 4CP consisted of four chambers each containing 65 m3 of sulfidic waste material. The 4CP enabled the transfer of laboratory results to a technical scale. The detergent sodiumdodecylsulfate (SDS) was proved to be active against the leaching bacteria. Organotrophic micro-organisms were not effected by the SDS application. The alkaline layers caused an increase of pH, however, a decrease of cell numbers was measured only in adjacent ore layers, but not in the whole ore body. A rapid evaluation of the effects of these countermeasures on ARD formation became possible by microcalorimetric activity measurements for bioleaching.

[In vitro study of emulsions containing methoxsalen]. / Methoxszalen in vitro diffúziójának tanulmányozása emulziókból.

Vitiligo is an acute disease of skin with inflammation which means damage of melanocites, their defined partial paint lack. It is a frequent sickness which is very conspicuous and disturbing illness. For its treatment, systematically and topically psoralen-derivatives, UV-A radiation and other possibilities are used. Metoxsalen is one of them which is practically insoluble in water. Authors planned to increase the solubility of the pharmacon, and they studied with in vitro diffusion method, how the type of the emulsions influence the liberation and diffusion of metoxsalen.

Sulfur chemistry in bacterial leaching of pyrite.

In the case of pyrite bioleaching by Leptospirillum ferrooxidans, an organism without sulfur-oxidizing capacity, besides the production of tetra- and pentathionate, a considerable accumulation of elemental sulfur occurred. A similar result was obtained for chemical oxidation assays with acidic, sterile iron(III) ion-containing solutions. In the case of Thiobacillus ferrooxidans, only slight amounts of elemental sulfur were detectable because of the organism's capacity to oxidize sulfur compounds. In the course of oxidative, chemical pyrite degradation under alkaline conditions, the accumulation of tetrathionate, trithionate, and thiosulfate occurred. The data indicate that thiosulfate, trithionate, tetrathionate, and disulfane-monosulfonic acid are key intermediate sulfur compounds in oxidative pyrite degradation. A novel (cyclic) leaching mechanism is proposed which basically is indirect.

[The Oradea study regarding the epidemiology factors in ischemic cardiopathy]. / Studiul Oradea privind depistarea si epidemiologia factorilor de risc în cardiopatia ischemia. I) Hipercolesterolemia.

Cholesterolemia in a population of 100482 inhabitants of the Bihor district, subjected to screening for the risk factors in ischemic cardiopathy were studied. Together with hyperlipidemias other risk factors were detected: arterial hypertension, obesity, diabetes mellitus, smoking, ischemic alterations of the electrocardiogram, the influence of the noxious agents present at the working place, of the blood groups and disturbances of the menstrual cycle. The mean cholesteremia is of 205 ± 43.7 mgr% (M = 207 ± 43.7 mgr%; F = 204 ± 43.5 mgr%). The prevalence of cholesterolemia, in comparison with the higher normal limits in each age group over 15 years of age, is in the entire studied series, of 13.5%. The population in whom cholesterolemia exceeds 250 mgr% represents 13.92%.