Genetic variation in the Y chromosome and sex-biased DNA methylation in somatic cells in the mouse

Mammalian Genome - Several lines of evidence suggest that the presence of the Y chromosome influences DNA methylation of autosomal loci. To better understand the impact of the Y chromosome on...     

Energy‐Dense Snack Food Intake in Adolescence: Longitudinal Relationship to Weight and Fatness

Objective: The longitudinal relationship between the consumption of energy‐dense snack (EDS) foods and relative weight change during adolescence is uncertain. Using data from the Massachusetts Institute of Technology Growth and Development Study, the current analysis was undertaken to examine the longitudinal relationship of EDS food intake with relative weight status and percentage body fat and to examine how EDS food consumption is related to television viewing. Research Methods and Procedures: One hundred ninety‐six nonobese premenarcheal girls 8 to 12 years old were enrolled between 1990 and 1993 and followed until 4 years after menarche. At each annual follow‐up visit, data were collected on percentage body fat (%BF), BMI z score, and dietary intake. Categories of EDS foods considered were baked goods, ice cream, chips, sugar‐sweetened soda, and candy. Results: At study entry, girls had a mean ± SD BMI z score of ?0.27 ± 0.89, consumed 2.3 ± 1.7 servings of EDS foods per day, and consumed 15.7 ± 8.1% of daily calories from EDS foods. Linear mixed effects modeling indicated no relationship between BMI z score or %BF and total EDS food consumption. Soda was the only EDS food that was significantly related to BMI z score over the 10‐year study period, but it was not related to %BF. In addition, a significant, positive relationship was observed between EDS food consumption and television viewing. Discussion: In this cohort of initially nonobese girls, overall EDS food consumption does not seem to influence weight status or fatness change over the adolescent period.     

The structure of the epithelial surface of the gastrointestinal tract of Pikas (Ochotona pallasi and O. dauurica,Lagomorpha, Ochotonidae): Functional and species specificity

The macro- and microrelief of the surface of the digestive tract mucosa of two pika species—Pallas’s (Ochotona pallasi) and Daurian (O. dauurica)—were studied in detail using whole-mount preparations and scanning electron microscopy. The structural features of the intestinal mucosal surface specific of mammals, such as the formation of projections on the crest of the cecal spiral fold and microcells in the colonic ampulla, were studied. It was found that the colonic mucosa forms sparse large conical villi in pocket cavities and on the surface of muscle bands. Significant differences in the cecal mucosal relief were found between the species studied. The possible functional significance of the identified morphological features is discussed.     

Molecular genetic diversity of the Saccharomyces yeasts in Taiwan: Saccharomyces arboricola, Saccharomyces cerevisiae and Saccharomyces kudriavzevii

Genetic hybridization, sequence and karyotypic analyses of natural Saccharomyces yeasts isolated in different regions of Taiwan revealed three biological species: Saccharomyces arboricola, Saccharomyces cerevisiae and Saccharomyces kudriavzevii. Intraspecies variability of the D1/D2 and ITS1 rDNA sequences was detected among S. cerevisiae and S. kudriavzevii isolates. According to molecular and genetic analyses, the cosmopolitan species S. cerevisiae and S. kudriavzevii contain local divergent populations in Taiwan, Malaysia and Japan. Six of the seven known Saccharomyces species are documented in East Asia: S. arboricola, S. bayanus, S. cerevisiae, S. kudriavzevii, S. mikatae, and S. paradoxus.     

不同耕作措施对冬小麦-夏玉米复种连作系统土壤有机碳和水分利用效率的影响

在连续8年田间定位试验的基础上,分析了关中平原冬小麦 夏玉米复种连作系统2008—2009年连续两个生长季期间不同耕作措施(结合秸秆还田和不还田)对土壤有机碳和水分利用率的影响.结果表明: 相对于传统耕作,保护性耕作有利于土壤有机碳、水分利用效率和作物产量的提高,其中在“深松+秸秆还田”耕作模式下的增幅最高,土壤有机碳含量在0～30 cm土层增幅达到19.5%,水分利用效率和作物产量提高了16.9%和20.5%,而免耕模式则有效提高了0～10 cm土层有机碳含量.在该地区土壤和气候条件下,深松结合秸秆粉碎还田是最理想的耕作模式,最有利于土壤有机碳累积,并提高水分利用效率和作物产量.     

Molecular Markers for Differentiation between the Closely Related Dairy Yeast Kluyveromyces lactis var. lactis and Wild Kluyveromyces lactis Strains from the European “Krassilnikovii” Population

A comparative molecular genetic study of 37 Kluyveromyces strains of different origin has made it possible to find molecular markers that can differentiate between the dairy yeast Kluyveromyces lactis var. lactis and the genetically close wild Kl. lactis strains from the European “krassilnikovii” population, which are unable to ferment lactose. A restriction fragment length polymorphism analysis of the IGS2 rDNA region reveals two different AluI profiles, one of which corresponds to Kl. lactis var. lactis while the other corresponds to yeasts from the “krassilnikovii” population. The AluI restriction profile of the IGS2 region of the rDNA also makes it possible to differentiate between the physiologically similar species Kl. marxianus and Kl. lactis. The origin of clinical Kl. lactis var. lactis isolates is discussed.__________Translated from Mikrobiologiya, Vol. 74, No. 3, 2005, pp. 387–393.Original Russian Text Copyright © 2005 by Naumova, Sukhotina, Naumov.     

SOI-nanowire biosensor for detection of D-NFATc1 protein

The nanowire (NW) detection is one of the fast-acting and high-sensitive methods, which can recognize potentially relevant protein molecules. A NW-biosensor based on the silicon-on-insulator (SOI)-structures has been used for biospecific label-free real time detection of the NFATc1 (D-NFATc1) oncomarker. For this purpose, SOI-nanowires (NWs) were modified with aptamers against NFATc1 used as molecular probes. It was shown that using this biosensor it is possible to reach sensitivity of 10^?15 M. This sensitivity was comparable to that of the NW-biosensor with immobilized antibodies used as macromolecular probes. The results demonstrate that approaches used in this study are promising for development of sensor elements for high-sensitive diagnostics of diseases.     

Polymorphism of lactose genes in the dairy yeasts <Emphasis Type="Italic">Kluyveromyces marxianus</Emphasis>, potential probiotic microorganisms

Molecular karyotyping and Southern blot hybridization were used to investigate chromosomal polymorphism of the LAC genes controlling lactose fermentation in Kluyveromyces marxianus strains isolated from various dairy products and natural sources in Russia and CIS countries. Profound polymorphism of karyotype patterns and accumulation of LAC genes were observed in dairy K. marxianus strains. K. marxianus strains isolated from dairy products intensively fermented lactose at 37°C after one day of cultivation, while non-dairy strains exhibited delayed lactose fermentation or did not ferment it at all. Based on the fermentation tests, twelve K. marxianus strains were selected, which are of interest as potential probiotic microorganisms suitable for further molecular genetic studies and breeding.