[Specificity of the location of human chromosomes in the nucleus of a moving cell]. / Spetsifichnost' raspolozheniia khromosom cheloveka v iadre dvizhushcheisia kletki.

Data are presented on the distribution of centromeric heterochromatin of the human X-chromosome in the interphase nucleus of a moving cell. The in situ hybridization made it possible to obtain some results leading to the following conclusions: in moving fibroblasts centromeric heterochromatin of the X-chromosome is located in end regions of the interphase nucleus; there was no preferential localization noted of the centromeric region of the X-chromosome in the front or back areas of the nucleus as to the direction of the movement.

[Correlation of polymorphism of heterochromatin segments with hybridization on chromosome preparations of various cloned repeated human DNA sequences]. / O korreliatsii polimorfizma geterokhromaticheskikh segmentov s gibridizatsiei na khromosomnykh preparatakh nekotorykh klonirovannykh povtoriaiushchikhsia posledovatel'nostei DNK cheloveka.

Comparison between results of measurements of heterochromatic regions detected by differential C and DA/DAP1 staining and the hybridization data of two cloned repeated human DNA sequences one alphoid (pH S05) and the other the satellite DNA III (pPD18) on chromosome preparations was made. A positive correlation of heterochromatic region sizes on several chromosomes and the amount of label over them detected after hybridization with both alphoid and satellite sequences was shown, the correlation with the latter being more pronounced.

[Quantitative analysis of chromosomal localization of two human cloned satellite DNA III sequences by in situ hybridization]. / Kolichestvennyi analiz khromosomnoi lokalizatsii dvukh klonirovannykh posledovatel'nostei satellitnoi DNK III cheloveka s pomoshch'iu metoda gibridizatsii in situ.

Chromosomal location of two cloned human satellite DNA III sequences pPD9 and pPD18 has been studied in 30 individuals by in situ hybridization. Pericentromeric localization of the DNA subsets studied was found in practically all chromosomes of the set. The majority of label was observed over the pericentromeric region of chromosome 9 (38.3% for pPD18 clone and 26.2% for pPD9), the short arm of chromosome 15 (17.2% - the pPD9 clone and 10.6% - the pPD18 clone) and the distal part of the long arm of Y chromosome (19.6% - the pPD9 clone and 15.4% - the pPD18 clone). Besides significant interchromosomal differences, moderately pronounced interindividual differences were also detected in the number of grains over the regular sites of the chromosomal location. Pretreatment of slides with DA/DAPI induced differences in the results of quantitative analysis is described.

[Use of a cloned alphoid repetitive sequence of human DNA in studying the polymorphism of heterochromatin regions of chromosomes]. / Ispol'zovanie klonirovannoi al'foidnoi povtoriaiushcheisia posledovatel'nosti DNK cheloveka v izuchenii polimorfizma geterokhromatinovykh raionov khromosom.

Chromosomal location of the cloned fragment pHS05 of alphoid DNA from the collection of human PstI restricts has been studied in 38 individuals by in situ hybridization. Pericentromeric localization of the DNA fraction studied was found in practically all chromosomes of the set. Significant interchromosomal and poorly expressed interindividual differences were detected in a number of the copies of the sequence class investigated. The majority of the label (approx. 27%) was observed over the pericentromeric region of chromosome 3. No relationship was discovered between hybridization results and the pattern of Q-polymorphism.

[Molecular cytogenetic research on the polymorphism of segments of the constitutive heterochromatin in human chromosomes]. / Molekuliarno-tsitogeneticheskoe issledovanie polimorfizma uchastkov strukturnogo geterokhromatina khromosom cheloveka.

Cloned alpha-satellite DNA sequences were used to evaluate the specificity and possible variability of repetitive DNA in constitutive heterochromatin of human chromosomes. Five probes of high specificity to individual chromosomes (chromosomes 3, 11, 17, 18 and X) were hybridized in situ to metaphase chromosomes of different individuals. The stable position of alpha-satellite DNA sequences in definite heterochromatic regions of particular chromosomes was found. Therefore, the chromosome-specific alpha-satellite DNA sequences may be used as molecular markers for heterochromatic regions of certain human chromosomes. The significant interindividual differences in relative copy number of alpha-satellite DNA have been detected. The homologous chromosomes of many individuals were characterized by cytologically visible heteromorphisms, as shown by intensity of hybridization with chromosome-specific alpha-satellite DNA sequences. A special analysis of hybridization between homologues with morphological differences gives evidence for a high resolution power of in situ hybridization technique for evaluation of chromosome heteromorphisms. The approaches for detection of heteromorphisms in cases without morphological differences between homologues are discussed. The results obtained indicate that constitutive heterochromatin of human chromosomes is variable for amount of alpha-satellite DNA sequences. In situ hybridization of cloned satellite DNA sequences may be used as novel general approach to analysis of chromosome heteromorphisms in man.

[Unusual case of 18p- syndrome: diagnosis using a cloned DNA fragment]. / Neobychnyi sluchai sindroma 18p-: diagnostika s pomoshch'iu klonirovannogo fragmenta DNK.

The patient with atypical clinic picture of 18p- syndrome is described. The in situ hybridization technique was used to localize chromosome 18-specific cloned sequence to metaphase chromosomes of the proband. The predominant hybridization was found in pericentromeric regions of homologous chromosome 18. The amount of pericentromeric DNA measured by in situ hybridization was different in homologous chromosomes and the number of radioactive grains was statistically greater in the normal chromosome 18 than in the chromosome 18p-. The cause of asymmetrical hybridization of probes to homologous chromosomes 18 is discussed. The results obtained indicate that this probe may be useful in clinical cytogenetics for identification of chromosome 19 in metaphase and interphase cells, determination of breakpoints or studies of pericentromeric DNA polymorphisms.

[Cloned fragment of human alphoid DNA--a molecular marker of the pericentromeric region of chromosome 18]. / Klonirovannyi fragment al'foidnoi DNK cheloveka--molekuliarnyi marker pritsentromernogo raiona 18-i khromosomy.

From the library of cloned fragments of human DNA we have isolated two recombinant plasmids containing alphoid DNA sequences pBRHS13, pBRHS65. Both cloned sequences hybridized in situ predominantly to pericentromeric regions of chromosome 18 and with less intensity to pericentromeric regions of chromosomes 2, 9, 20, and were characterized by populational copy number polymorphism in homologous chromosomes. These sequences may appear very useful in the diagnostics and cytogenetic analysis of chromosomal aberrations and in studies of polymorphisms of heterochromatic regions of human chromosomes.

[Morphofunctional assessment of the respiratory tract of rabbits in the subacute form of oxygen poisoning]. / Morfofunktsional'naia otsenka sistemy vneshnego dykhaniia u krolikov pri podostroi forme otravleniia kislorodom.

Rabbits were exposed to hyperoxic experiments (2.5--3.0 kg/cm2 O2 for 3--4 h and 2.0 kg/cm2 O2 for 16--22 h until death) to study changes in their respiratory and cardiovascular systems. After exposure one lung was used for histological examinations under light microscope and the other to determine the surfactant stability index. It was found that serious changes in the respiratory and cardiovascular systems in all animals (including those who died during exposure) were not followed by histological changes of the lungs. Therefore, the pathogenetic mechanisms of subacute (pulmonary) oxygen intoxication are associated with disorders in the central regulation of autonomic functions rather than with direct lesions of the pulmonary tissue.