RESUMEN
Regional and local climate change depends on continentality, orography, and human activities. In particular, local climate modification by water reservoirs can reach far from shore and downstream. Among the possible ecological consequences are shifts in plant performance. Tree-ring width of affected trees can potentially be used as proxies for reservoir impact. Correlation analysis and t-tests were applied to climatic data and tree-ring chronologies of Pinus sylvestris L. and Larix sibirica Ledeb. from moisture-deficit habitats in the intermontane Khakass-Minusinsk Depression, to assess modification of climate and tree growth by the Krasnoyarsk and Sayano-Shushenskoe Reservoirs on the Yenisei River. Abrupt significant cooling in May-August and warming in September-March occurred after the launch of the turbines in dams, more pronounced near the Sayano-Shushenskoe dam (up to - 0.5 °C in summer and to + 3.5 °C in winter) than near the Krasnoyarsk Reservoir headwaters (- 0.3 °C and + 1.4 °C). Significant lengthening of the warm season was also found for temperature thresholds 0-8 °C. Shifts of seasonality and intensity occurred in climatic responses of all tree-ring chronologies after development of water reservoirs. Patterns of these shifts, however, depended on species-specific sensitivity to climatic modification, distance from reservoirs, and physiographic regions. Mitigation of climate continentality and extremes by reservoirs appears to have offset possible negative effects of warming on tree growth.
RESUMEN
A modified system with two pairs of primers is suggested for the analysis of different bcr/abl mRNA variants, using the polymerase chain reaction (PCR) method. It was demonstrated that, with the use of this method, mRNA preparations obtained from bone marrow cells are more informative than those obtained from blood cells. Fresh preparations of thermostable Tth DNA polymerase, which exhibited the reverse transcriptase activity, appeared to be optimal for PCR analysis of the bcr/abl mRNA pattern.
Asunto(s)
Proteínas de Fusión bcr-abl/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , ARN Mensajero/metabolismo , Secuencia de Bases , Cartilla de ADN , ADN Polimerasa Dirigida por ADN/metabolismo , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , ADN Polimerasa Dirigida por ARN/metabolismoRESUMEN
The site of the break of chromosome 22 was investigated by blot hybridization and polymerase chain reaction in 41 patients with chronic myeloid leukemia (CML). It is stated that the break site in various regions is not associated with the disease stage and clinicohematological manifestations in the time of the diagnosis. The break in the 5' subregion was indicative of longer survival than that in the subregion 3' patients. Median survival reached 60.8 and 32.4 months, respectively.
Asunto(s)
Cromosomas Humanos Par 22 , Cromosomas Humanos Par 9 , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Translocación Genética , Adolescente , Adulto , Anciano , ADN de Neoplasias/genética , Femenino , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/mortalidad , Masculino , Persona de Mediana Edad , Cromosoma Filadelfia , Pronóstico , ARN Neoplásico/genéticaRESUMEN
Using oligonucleotide probes, sequences containing the Mbcr locus involved in chromosome translocation t(9:22) were cloned form the library of human genes in the Charon 4A vector. The recombinant clone lambda BCR 1.1 obtained contained Mbcr sequences, but the 3' region of the Mbcr locus in lambda BCR 1.1 clone was strongly altered. Subcloning of a fragment of the altered region and blot hybridization analysis using it as a DNA probe revealed recombination in the 3' region of the Mbcr locus in clone lambda BCR 1.1 which resulted in insertion of unknown sequences into the region. A modified system is suggested for chromosome 22 breakpoint identification using restriction analysis of genome DNA with four restriction endonucleases and one 5'-DNA probe.
Asunto(s)
Cromosomas Humanos Par 22 , Cromosomas Humanos Par 9 , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Translocación Genética , Secuencia de Bases , Clonación Molecular , Humanos , Datos de Secuencia Molecular , Sondas de Oligonucleótidos , Recombinación Genética , Mapeo RestrictivoRESUMEN
The presence of considerable level of phenotypic variability for the nature of fertility change in conditions of imago density increase has been shown in Drosophila natural populations. Genetic peculiarities of insects play the main role in its determination. The genotype groups sensitive and stable to density increase exist in the populations. The former have relatively high fertility at low density and low fertility at overcrowding. The latter are of contrary nature of fertility at given density conditions.