86 research outputs found
Measurement of the charge carrier mobility in MEH-PPV and MEH-PPV-POSS organic semiconductor films
A standard photomap of ovarian nurse cell chromosomes and inversion polymorphism in Anopheles beklemishevi
Background Anopheles beklemishevi is a member of the Maculipennis group of malaria mosquitoes that has the most northern distribution among other members of the group. Although a cytogenetic map for the larval salivary gland chromosomes of this species has been developed, a high-quality standard cytogenetic photomap that enables genomics and population genetics studies of this mosquito at the adult stage is still lacking. Methods In this study, a cytogenetic map for the polytene chromosomes of An. beklemishevi from ovarian nurse cells was developed using high-resolution digital imaging from field collected mosquitoes. PCR-amplified DNA probes for fluorescence in situ hybridization (FISH) were designed based on the genome of An. atroparvus. The DNA probe obtained by microdissection procedures from the breakpoint region was labelled in a DOP-PCR reaction. Population analysis was performed on 371 specimens collected in 18 locations. Results We report the development of a high-quality standard photomap for the polytene chromosomes from ovarian nurse cells of An. beklemishevi. To confirm the suitability of the map for physical mapping, several PCR-amplified probes were mapped to the chromosomes of An. beklemishevi using FISH. In addition, we identified and mapped DNA probes to flanking regions of the breakpoints of two inversions on chromosome X of this species. Inversion polymorphism was determined in 13 geographically distant populations of An. beklemishevi. Four polymorphic inversions were detected. The positions of common chromosomal inversions were indicated on the map. Conclusions The study constructed a standard photomap for ovarian nurse cell chromosomes of An. beklemishevi and tested its suitability for physical genome mapping and population studies. Cytogenetic analysis determined inversion polymorphism in natural populations of An. beklemishevi related to this species’ adaptatio
Взаимосвязь между сахарным диабетом и раком поджелудочной железы
Experience of treating 183 pancreatic cancer patients was summarized. The frequency of carbohydrate metabolism disorder and time dependence between the onset of diabetes and pancreatic cancer detection were examined. It was found that 133 (72.7 %) patients had glucose intolerance. Diabetes mellitus was detected in 49 (26.8 %) patients and 28 of them (57.2 %) had new-onset diabetes. In the latter group of patients, it can be considered that detection of endocrine disease was an early sign of pancreatic cancer.Обобщен опыт лечения 183 больных раком поджелудочной железы. У пациентов исследовались частота нарушения углевод- ного обмена, а также временная зависимость между началом сахарного диабета и выявлением опухоли поджелудочной железы. Установлено, что у 133 (72,7 %) пациентов наблюдалось нарушение метаболизма глюкозы, сахарный диабет установлен у 49 (26,8 %), причем у 28 (57,2 %) был впервые выявленным
Microstructure and properties of a silicon coating deposited on a titanium nickelide substrate using molecular-beam epitaxy equipment
The microstructure and properties of a silicon coating on a titanium nickelide substrate were studied to assess the possibility of using such a coating to improve the biocompatibility of medical implants. The silicon coating with thickness of 4.0±0.5 microns was applied to the TiNi substrate on a molecular beam epitaxy unit. The coating had a submicrocrystalline structure with a crystallite size of 0.1...0.2 microns, a developed surface, and high crack resistance
Mitotic-chromosome-based physical mapping of the Culex quinquefasciatus genome
The genome assembly of southern house mosquito Cx. quinquefasciatus is represented by a high number of supercontigs with no order or orientation on the chromosomes. Although cytogenetic maps for the polytene chromosomes of this mosquito have been developed, their utilization for the genome mapping remains difficult because of the low number of high-quality spreads in chromosome preparations. Therefore, a simple and robust mitotic-chromosome-based approach for the genome mapping of Cx. quinquefasciatus still needs to be developed. In this study, we performed physical mapping of 37 genomic supercontigs using fluorescent in situ hybridization on mitotic chromosomes from imaginal discs of 4th instar larvae. The genetic linkage map nomenclature was adopted for the chromosome numbering based on the direct positioning of 58 markers that were previously genetically mapped. The smallest, largest, and intermediate chromosomes were numbered as 1, 2, and 3, respectively. For idiogram development, we analyzed and described in detail the morphology and proportions of the mitotic chromosomes. Chromosomes were subdivided into 19 divisions and 72 bands of four different intensities. These idiograms were used for mapping the genomic supercontigs/genetic markers. We also determined the presence of length polymorphism in the q arm of sex-determining chromosome 1 in Cx. quinquefasciatus related to the size of ribosomal locus. Our physical mapping and previous genetic linkage mapping resulted in the chromosomal assignment of 13% of the total genome assembly to the chromosome bands. We provided the first detailed description, nomenclature, and idiograms for the mitotic chromosomes of Cx. quinquefasciatus. Further application of the approach developed in this study will help to improve the quality of the southern house mosquito genome
Effect of a boron implantation on the electrical properties of epitaxial HgCdTe with different material composition
In this work the experimental results of investigations of the dynamics of accumulation and spatial distribution of electrically active radiation defects when irradiating epitaxial films of Hg1-xCdxTe (MCT) with different material composition (x). The films, grown by molecular beam epitaxy (MBE) were irradiated by B ions at room temperature in the radiation dose range 1012 -1015 ions/cm2 and with ion energy 100 keV. The results give the differences in implantation profiles, damage accumulation and electrical properties as a function of the material composition of the film
Phylogenomics revealed migration routes and adaptive radiation timing of holarctic malaria mosquito species of the Maculipennis group
BackgroundPhylogenetic analyses of closely related species of mosquitoes are important for better understanding the evolution of traits contributing to transmission of vector-borne diseases. Six out of 41 dominant malaria vectors of the genus Anopheles in the world belong to the Maculipennis Group, which is subdivided into two Nearctic subgroups (Freeborni and Quadrimaculatus) and one Palearctic (Maculipennis) subgroup. Although previous studies considered the Nearctic subgroups as ancestral, details about their relationship with the Palearctic subgroup, and their migration times and routes from North America to Eurasia remain controversial. The Palearctic species An. beklemishevi is currently included in the Nearctic Quadrimaculatus subgroup adding to the uncertainties in mosquito systematics.ResultsTo reconstruct historic relationships in the Maculipennis Group, we conducted a phylogenomic analysis of 11 Palearctic and 2 Nearctic species based on sequences of 1271 orthologous genes. The analysis indicated that the Palearctic species An. beklemishevi clusters together with other Eurasian species and represents a basal lineage among them. Also, An. beklemishevi is related more closely to An. freeborni, which inhabits the Western United States, rather than to An. quadrimaculatus, a species from the Eastern United States. The time-calibrated tree suggests a migration of mosquitoes in the Maculipennis Group from North America to Eurasia about 20-25 million years ago through the Bering Land Bridge. A Hybridcheck analysis demonstrated highly significant signatures of introgression events between allopatric species An. labranchiae and An. beklemishevi. The analysis also identified ancestral introgression events between An. sacharovi and its Nearctic relative An. freeborni despite their current geographic isolation. The reconstructed phylogeny suggests that vector competence and the ability to enter complete diapause during winter evolved independently in different lineages of the Maculipennis Group.ConclusionsOur phylogenomic analyses reveal migration routes and adaptive radiation timing of Holarctic malaria vectors and strongly support the inclusion of An. beklemishevi into the Maculipennis Subgroup. Detailed knowledge of the evolutionary history of the Maculipennis Subgroup provides a framework for examining the genomic changes related to ecological adaptation and susceptibility to human pathogens. These genomic variations may inform researchers about similar changes in the future providing insights into the patterns of disease transmission in Eurasia
The Russian consensus on the diagnosis and treatment of chronic pancreatitis: Enzyme replacement therapy
The Russian consensus on the diagnosis and treatment of chronic pancreatitis has been prepared on the initiative of the Russian Pancreatology Club to clarify and consolidate the opinions of Russian specialists (gastroenterologists, surgeons, and pediatricians) on the most significant problems of diagnosis and treatment of chronic pancreatitis. This article continues a series of publications explaining the most significant interdisciplinary consensus statements and deals with enzyme replacement therapy
Встречаемость мутаций в генах BRCA1 и BRCA2 у больных раком поджелудочной железы
BRCA1 and BRCA2 may contribute in pancreatic cancer (PC) risk, however the selection criteria for BRCA1 testing are poorly defined. The analysis of Russian founder mutation BRCA1 5382insC in 150 PC patients identified 2 carriers. BRCA2 full-length sequencing of 8 DNA samples revealed 1 mutated allele (BRCA2 5197_5198delTC). All 3 carriers of BRCA1/2 mutations reported personal or familial history of BRCA-related cancers. Thus, BRCA1/2 testing is particularlyМутации в генах BRCA1 и BRCA2 могут играть роль в формировании риска рака поджелудочной железы (РПЖ), однако критерии включения пациентов в BRCA-диагностику остаются неясными. Присутствие повторяющейся мутации BRCA1 5382insC анализировалось у 150 больных РПЖ, при этом выявлено 2 носителя упомянутого аллеля. Полный анализ кодирующей области гена BRCA2 выполнен у 8 пациентов, обнаружен 1 дефектный вариант (BRCA2 5197_5198delTC). Все 3 больных с мутацией имели собственный или семейный анамнез BRCA-ассоциированных онкологических заболеваний. Таким образом, BRCA-тестирование случаев РПЖ целесообразно ограничить только теми пациентами, у которых имеются клинические признаки наследственного характера заболевани
Russian consensus on exoand endocrine pancreatic insufficiency after surgical treatment
The Russian consensus on exo - and endocrine pancreatic insufficiency after surgical treatment was prepared on the initiative of the Russian "Pancreatic Club" on the Delphi method. His goal was to clarify and consolidate the opinions of specialists on the most relevant issues of diagnosis and treatment of exo - and endocrine insufficiency after surgical interventions on the pancreas. An interdisciplinary approach is provided by the participation of leading gastroenterologists and surgeons
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