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171.
172.
Kirchengast S Mayer M Voigt M 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2007,65(4):415-426
Human reproduction is a biological phenomenon, however, sociocultural factors such as marital status influence pregnancy outcome and reproductive success. In the present study the impact of maternal marital status on pregnancy outcome was tested for all births, which had taken place in Austria between 1999 and 2004, which met the following criteria: single births, nulliparity, mothers older than 19 years (n = 179 830). The rate of preterm delivery (< 37 beginning weeks of gestation) and rate of low birth weight (< 2500 g) among term births were significantly higher among unmarried mothers in comparison to married mothers. Additionally the newborns of unmarried mothers were significantly lighter and shorter than those of married mothers. This was especially true of immigrant mothers. No significant differences between married and unmarried mothers were found regarding mode of delivery. Even at the beginning of the 21st century unmarried status represents an important stress factor for pregnant women. 相似文献
173.
The morphology proteins Mdm12/Mmm1 function in the major beta-barrel assembly pathway of mitochondria 下载免费PDF全文
Meisinger C Pfannschmidt S Rissler M Milenkovic D Becker T Stojanovski D Youngman MJ Jensen RE Chacinska A Guiard B Pfanner N Wiedemann N 《The EMBO journal》2007,26(9):2229-2239
The beta-barrel proteins of mitochondria are synthesized on cytosolic ribosomes. The proteins are imported by the translocase of the outer membrane (TOM) and the sorting and assembly machinery (SAM). It has been assumed that the SAM(core) complex with the subunits Sam35, Sam37 and Sam50 represents the last import stage common to all beta-barrel proteins, followed by splitting in a Tom40-specific route and a route for other beta-barrel proteins. We have identified new components of the beta-barrel assembly machinery and show that the major beta-barrel pathway extends beyond SAM(core). Mdm12/Mmm1 function after SAM(core) yet before splitting of the major pathway. Mdm12/Mmm1 have been known for their role in maintenance of mitochondrial morphology but we reveal assembly of beta-barrel proteins as their primary function. Moreover, Mdm10, which functions in the Tom40-specific route, can associate with SAM(core) as well as Mdm12/Mmm1 to form distinct assembly complexes, indicating a dynamic exchange between the machineries governing mitochondrial beta-barrel assembly. We conclude that assembly of mitochondrial beta-barrel proteins represents a major function of the morphology proteins Mdm12/Mmm1. 相似文献
174.
BACKGROUND: The objective of this study was to identify factors motivating women to take part in endometriosis research and to determine if these factors differ for women participating in clinical versus basic science studies. METHODS: A consecutive series of 24 women volunteering for participation in endometriosis-related research were asked to indicate, in their own words, why they chose to volunteer. In addition, the women were asked to rate, on a scale of 0 to 10, sixteen potentially motivating factors. The information was gathered in the form of an anonymous self-administered questionnaire. RESULTS: Strong motivating factors (mean score > 8) included potential benefit to other women's health, improvement to one's own condition, and participation in scientific advancement. Weak motivating factors (mean score < 3) included financial compensation, making one's doctor happy, and use of 'natural' products. No difference was detected between clinical and basic science study participants. CONCLUSION: This study is the first study to specifically investigate the factors that motivate women to take part in endometriosis research. Understanding why women choose to take part in such research is important to the integrity of the informed consent process. The factors most strongly motivating women to participate in endometriosis research related to improving personal or public health; the weakest, to financial compensation and pleasing the doctor. 相似文献
175.
Extracting binary signals from microarray time-course data 总被引:1,自引:0,他引:1
This article presents a new method for analyzing microarray time courses by identifying genes that undergo abrupt transitions in expression level, and the time at which the transitions occur. The algorithm matches the sequence of expression levels for each gene against temporal patterns having one or two transitions between two expression levels. The algorithm reports a P-value for the matching pattern of each gene, and a global false discovery rate can also be computed. After matching, genes can be sorted by the direction and time of transitions. Genes can be partitioned into sets based on the direction and time of change for further analysis, such as comparison with Gene Ontology annotations or binding site motifs. The method is evaluated on simulated and actual time-course data. On microarray data for budding yeast, it is shown that the groups of genes that change in similar ways and at similar times have significant and relevant Gene Ontology annotations. 相似文献
176.
In the present study the menarcheal status (pre-or postmenarcheal), body composition, weight status, and socioeconomic parameters such as type of school and parental educational level as of 1752 female adolescents ageing between 12 and 18 years (x = 14.6) from rural areas of Eastern Austria were documented. Furthermore the association patterns between body composition, socioeconomic parameters and menarcheal status were analyzed. It turned out, that body composition parameters such as BMI, lean body mass and absolute and relative fat mass were significantly associated with menarcheal status. Postmenarcheal girls were taller and exhibited a higher weight status, a higher absolute and relative amount of fat mass and a higher amount of lean body mass than their premenarcheal counterparts of the same age. In contrast to the significant association between body composition and menarcheal status, no significant impact of educational level on menarcheal status, indicating socioeconomic status could be documented. 相似文献
177.
Life in a social group increases the risk of disease transmission. To counteract this threat, social insects have evolved manifold antiparasite defenses, ranging from social exclusion of infected group members to intensive care. It is generally assumed that individuals performing hygienic behaviors risk infecting themselves, suggesting a high direct cost of helping. Our work instead indicates the opposite for garden ants. Social contact with individual workers, which were experimentally exposed to a fungal parasite, provided a clear survival benefit to nontreated, naive group members upon later challenge with the same parasite. This first demonstration of contact immunity in Social Hymenoptera and complementary results from other animal groups and plants suggest its general importance in both antiparasite and antiherbivore defense. In addition to this physiological prophylaxis of adult ants, infection of the brood was prevented in our experiment by behavioral changes of treated and naive workers. Parasite-treated ants stayed away from the brood chamber, whereas their naive nestmates increased brood-care activities. Our findings reveal a direct benefit for individuals to perform hygienic behaviors toward others, and this might explain the widely observed maintenance of social cohesion under parasite attack in insect societies. 相似文献
178.
Lamins and lamin-associated proteins in aging and disease 总被引:5,自引:0,他引:5
Lamins, together with the lamin-associated proteins of the inner nuclear membrane, are structural proteins in the nucleus that mediate mechanical stress resistance. Novel findings show that lamin complexes also have scaffolding functions in the formation and regulation of higher order chromatin and in epigenetic regulatory pathways. Furthermore, lamins serve as scavenging complexes and regulators of signaling molecules in diverse pathways. Lamin complexes in the nuclear interior contribute to retinoblastoma-mediated cell cycle regulation. Because of their multiple and diverse roles, lamins are linked to an increasing number of human diseases. The molecular mechanisms of these diseases, which are just beginning to emerge, may involve cell cycle and differentiation defects in adult stem cells and genomic instability. 相似文献
179.
Shapo JL Moeller PD Galloway SB 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2007,148(1):65-73
Antimicrobial activity was examined in the gorgonian Leptogorgia virgulata (common seawhip) from South Carolina waters. Extraction and assay protocols were developed to identify antimicrobial activity in crude extracts of L. virgulata. Detection was determined by liquid growth inhibition assays using Escherichia coli BL21, Vibrio harveyii, Micrococcus luteus, and a Bacillus sp. isolate. This represents the first report of antimicrobial activity in L. virgulata, a temperate/sub-tropical coral of the western Atlantic Ocean. Results from growth inhibition assays guided a fractionation scheme to identify active compounds. Reverse-phase HPLC, HPLC-mass spectrometry, and 1H and 13C NMR spectroscopy were used to isolate, purify, and characterize metabolites in antimicrobial fractions of L. virgulata. Corroborative HPLC-MS/NMR evidence validated the presence of homarine and a homarine analog, well-known emetic metabolites previously isolated from L. virgulata, in coral extracts. In subsequent assays, partially-purified L. virgulata fractions collected from HPLC-MS fractionation were shown to contain antimicrobial activity using M. luteus and V. harveyii. This study provides evidence that homarine is an active constituent of the innate immune system in L. virgulata. We speculate it may act synergistically with cofactors and/or congeners in this octocoral to mount a response to microbial invasion and disease. 相似文献
180.
Ataxin-2 interacts with the DEAD/H-box RNA helicase DDX6 and interferes with P-bodies and stress granules 下载免费PDF全文
Nonhoff U Ralser M Welzel F Piccini I Balzereit D Yaspo ML Lehrach H Krobitsch S 《Molecular biology of the cell》2007,18(4):1385-1396
Tight control of translation is fundamental for eukaryotic cells, and deregulation of proteins implicated contributes to numerous human diseases. The neurodegenerative disorder spinocerebellar ataxia type 2 is caused by a trinucleotide expansion in the SCA2 gene encoding a lengthened polyglutamine stretch in the gene product ataxin-2, which seems to be implicated in cellular RNA-processing pathways and translational regulation. Here, we substantiate a function of ataxin-2 in such pathways by demonstrating that ataxin-2 interacts with the DEAD/H-box RNA helicase DDX6, a component of P-bodies and stress granules, representing cellular structures of mRNA triage. We discovered that altered ataxin-2 levels interfere with the assembly of stress granules and cellular P-body structures. Moreover, ataxin-2 regulates the intracellular concentration of its interaction partner, the poly(A)-binding protein, another stress granule component and a key factor for translational control. Thus, our data imply that the cellular ataxin-2 concentration is important for the assembly of stress granules and P-bodies, which are main compartments for regulating and controlling mRNA degradation, stability, and translation. 相似文献