Roentgeno-endovascular surgery of hypofunctional ovaries in varicosities of the ovarian veins]

Three degrees of ovarian varicocele in sterile women or women with menstrual disturbance were described on the basis of analysis of 62 superselective ovariophlebograms. A nonsurgical pathogenetic method for correction of ovarian hypofunction in disturbed circulation in the venous region of the pelvic organs was developed by cutting off the ovarian vein from the pathological renocaval vascular shunt with the help of roentgenovascular intervention. It is based upon transcatheter occlusion of the left ovarian vein and directly follows diagnostic phlebography. Roentgenoendovascular occlusion of the left ovarian vein was performed in 41 patients Ivanissevich's operation--in 8 patients. In 4-18 months after intervention, improved results of a clinical picture and functional diagnostic tests were observed in 46 patients. Of 19 women with passable uterine tubes 14 got pregnant.     

Molecular Genetic Analysis of the Yeast Komagataea (Williopsis) pratensisStrains Isolated from the Caucasian and Tien Shan Soils

The analysis of sixteen Komagataea (Williopsis) pratensisisolates from Caucasian and Tien Shan soils by the PCR, blot hybridization, and isoenzyme electrophoresis techniques showed that fifteen of them do belong to the species K. pratensis. The isolates from the two geographic areas differed in some physiological characteristics and in the PCR product profiles obtained with the microsatellite primers (CAC)₅and (GACA)₄.     

A new family of polymorphic metallothionein-encoding genes MTH1 (CUP1) and MTH2 in Saccharomyces cerevisiae.

By pulsed-field gel electrophoresis of chromosomal DNA and hybridization with a cloned MTH1 (CUP1) gene, we determined the locations of metallothionein-encoding gene sequences on chromosomes in monosporic cultures of 76 natural strains of Saccharomyces cerevisiae. Most of the strains (68) exhibited a previously known location for the MTH sequence on chromosome (chr.) VIII. Seven strains (resistant or sensitive to Cu2+) showed a MTH sequence in a new locus, MTH2, on chr. XVI. One strain carried an MTH locus on both chromosomes VIII and XVI. Restriction fragment and Southern blot analyses showed that the two MTH loci were very closely related. The strains displayed heterogeneity in the size and structure of their MTH2 locus. The length of the repeat unit of MTH2 varied: a 1.9-kb or 1.7-kb unit was found, instead of the 2.0-kb unit of the MTH1 locus. The most resistant strain (resistant to 1.2 mM CuSO4) contained a 0.9-kb repeat unit in addition to those of 1.9 kb and 1.7 kb. All three sensitive (to over 0.3 mM CuSO4) strains with an mth2 locus had a repeat unit of 1.9 kb or 1.7 kb, suggesting the presence of at least two copies of the MTH2 gene, with one always being in the junction area outside of the repeat unit. A monogenic tetrad segregation of 2:2 was usually found in crosses of resistant MTH2 and sensitive mth2 strains. Hybrids between strains with different MTH loci in all combinations showed low ascospore viability, suggesting that the complete lack of an MTH locus may lead to the death of segregants on YPD medium. The MTH1 and MTH2 loci were exchangeable. Strains with a high level of Cu2+ resistance were also resistant to Cd2+. However, these two properties did not cosegregate in heterozygotic hybrids.     

Target highlights in CASP13: Experimental target structures through the eyes of their authors

The functional and biological significance of selected CASP13 targets are described by the authors of the structures. The structural biologists discuss the most interesting structural features of the target proteins and assess whether these features were correctly reproduced in the predictions submitted to the CASP13 experiment.     

The Chromosome End in Yeast: Its Mosaic Nature and Influence on Recombinational Dynamics

Yeast chromosome ends are composed of several different repeated elements. Among six clones of chromosome ends from two strains of Saccharomyces cerevisiae, at least seven different repeated sequence families were found. These included the previously identified Y'' and X elements. Some families are highly variable in copy number and location between strains of S. cerevisiae, while other elements appear constant in copy number and location. Three repeated sequence elements are specific to S. cerevisiae and are not found in its evolutionarily close relative, Saccharomyces paradoxus. Two other repeated sequences are found in both S. cerevisiae and S. paradoxus. None of those described here is found (by low stringency DNA hybridization) in the next closest species, Saccharomyces bayanus. The loosely characterized X element is now more precisely defined. X is a composite of at least four small (ca. 45-140 bp) sequences found at some, but not all, ends. There is also a potential ``core'''' X element of approximately 560 bp which may be found at all ends. Distal to X, only one of six clones had (TG(1-3))(n) telomere sequence at the junction between X and Y''. The presence of these internal (TG(1-3))(n) sequences correlates with the ability of a single Y'' to expand into a tandem array of Y''s by unequal sister chromatid exchange. The presence of shared repeated elements proximal to the X region can override the strong preference of Y''s to recombine ectopically with other Y''s of the same size class. The chromosome ends in yeast are evolutionarily dynamic in terms of subtelomeric repeat structure and variability.