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101.
Kornhuber J Erhard G Lenz B Kraus T Sperling W Bayerlein K Biermann T Stoessel C 《PloS one》2011,6(4):e19332
The ratio of the lengths of the second and fourth finger (2D∶4D) has been described as reflecting the degree of prenatal androgen exposure in humans. 2D∶4D is smaller for males than females and is associated with traits such as left-handedness, physical aggression, attention-deficit-hyperactivity disorder and a genetic polymorphism of the androgen receptor. All of these traits are known to be correlated to the vulnerability for alcohol dependency. We therefore hypothesized low 2D∶4D in patients with alcohol dependency. In the present study on 131 patients suffering from alcohol dependency and 185 healthy volunteers, we found that alcohol dependent patients had smaller 2D∶4D ratios compared to controls with preserved sexual dimorphism but with reduced right-left differences. The detection of alcohol dependency based on 2D∶4D ratios was most accurate using the right hand of males (ROC-analysis: AUC 0.725, sensitivity 0.667, specificity 0.723). These findings provide novel insights into the role of prenatal androgen exposure in the development of alcohol dependency and for the use of 2D∶4D as a possible trait marker in identifying patients with alcohol dependency. 相似文献
102.
Brower-Toland B Wacker DA Fulbright RM Lis JT Kraus WL Wang MD 《Journal of molecular biology》2005,346(1):135-146
The distinct contributions of histone tails and their acetylation to nucleosomal stability were examined by mechanical disruption of individual nucleosomes in a single chromatin fiber using an optical trap. Enzymatic removal of H2A/H2B tails primarily decreased the strength of histone-DNA interactions located approximately +/-36bp from the dyad axis of symmetry (off-dyad strong interactions), whereas removal of the H3/H4 tails played a greater role in regulating the total amount of DNA bound. Similarly, nucleosomes composed of histones acetylated to different degrees by the histone acetyltransferase p300 exhibited significant decreases in the off-dyad strong interactions and the total amount of DNA bound. Acetylation of H2A/H2B appears to play a particularly critical role in weakening the off-dyad strong interactions. Collectively, our results suggest that the destabilizing effects of tail acetylation may be due to elimination of specific key interactions in the nucleosome. 相似文献
103.
Gekkotaenia novaeguineaensis n. gen., n. sp. (Cestoda: Anoplocephalidae) from the small intestine and Cosmocerca zugi n. sp. (Nematoda: Cosmocercidae) from the large intestine of the ring-tailed gecko, Cyrtodactylus louisiadensis (Sauria: Gekkonidae) are described and illustrated. Gekkotaenia novaeguineaensis n. gen., n. sp. is unique among the acraspedote Linstowiinae in possessing a poral female reproductory system. Cosmocerca zugi n. sp. is the 22nd species to be assigned to the genus and differs from other species in the genus by possessing 4 pairs of rosette papillae on plectanes and having a gubernaculum longer than the spicules. It is the fifth species to be described from the Australian biogeographical region. Eight additional helminth species were found: the digenean, Allopharynx macallisteri; 2 cestodes, cysticercoids of Cyclophyllidea gen. sp. and tetrathyridia of Mesocestoides sp.; 5 nematodes, larvae in cysts of Abbreviata sp., Aplectana macintoshii, Oswaldocruzia bakeri, Parapharyngodon maplestonei, and an undescribed species of Physalopteroides. Cyrtodactylus louisiadensis represents a new host record for each of these helminths. 相似文献
104.
C.?C.?Nievola J.?E.?Kraus L.?Freschi B.?M.?Souza H.?MercierEmail author 《In vitro cellular & developmental biology. Plant》2005,41(6):832-837
Summary
Ananas comosus (L.) Merr. var. Smooth Cayenne plants when grown in vitro under different temperature regimes developed as CAM or as C3 plants. The plants used in this study were developed from the lateral buds of the nodal etiolated stem explants cultured
on Murashige and Skoog medium for 3 mo. The cultures were maintained under a 16-h photoperiod for different thermoperiods.
With 28°C light/15°C dark thermoperiod, as compared with constant 28°C light and dark, pineapple plants had a succulence index
two times greater, and also a greater nocturnal titratable acidity and phosphoenolpyruvate carboxylase (PEPCase) activity,
indicating CAM-type photosynthesis. The highest abscisic acid (ABA) level occurred during the light period, 8 h prior to maximum
PEPCase activity, while the indole-3-acetic acid (IAA) peak was found during the dark period, coinciding with the time of
highest PEPCase activity. These plants were also smaller with thicker leaves and fewer roots, but had greater dry weight.
Their leaves showed histological characteristics of CAM plants, such as the presence of greater quantities of chlorenchyma
and hypoderm. In addition, their vascular system was more conspicuous. In contrast, under constant temperature (28°C light/dark)
plants showed little succulence in the leaves. There was no significant acid oscillation and diurnal variation in PEPCase
activity in these plants, suggesting the occurrence of C3 photosynthesis. Also, no diurnal variation in ABA and IAA contents was observed. The results of this study clearly indicate
a role for temperature in determining the type of carbon fixation pathway in in vitro grown pineapple. Evidence that ABA and IAA participate in CAM signaling is provided. 相似文献
105.
Tasler S Kraus J Pegoraro S Aschenbrenner A Poggesi E Testa R Motta G Leonardi A 《Bioorganic & medicinal chemistry letters》2005,15(11):2876-2880
Based on a pharmacophore alignment on known non-competitive mGluR5 inhibitors applying 4SCan technology, a new lead series was identified and further structurally investigated. K(i)'s as low as around 100 nM were achieved. 相似文献
106.
Copper was added to truncated, recombinant cystathionine beta-synthase (CBS), and the enzyme activity was assessed by measuring the production of cystathionine. 10 microM copper significantly decreased CBS activity by 50% while 25 microM copper decreased CBS activity by 70%. This inhibition was negated when an analog of the N-terminus of human albumin, Asp-Ala-His-Lys (DAHK), a strong transition metal binding peptide, was added. The use of copper chelators could significantly reduce in vivo homocysteine levels. 相似文献
107.
108.
The maturation of Borna disease virus (BDV) glycoprotein GP was studied in regard to intracellular compartmentalization, compartmentalization signal-domains, proteolytic processing, and packaging into virus particles. Our data show that BDV-GP is (i) predominantly located in the endoplasmic reticulum (ER), (ii) partially exists in the ER already as cleaved subunits GP-N and GP-C, (iii) is directed to the ER/cis-Golgi region by its transmembrane and/or cytoplasmic domains in CD8-BDV-GP hybrid constructs and (iv) is incorporated in the virus particles as authentic BDV glycoprotein exclusively in the cleaved form decorated with N-glycans of the complex type. Downregulation of BDV-glycoproteins on the cell surface, their limited proteolytic processing, and protection of antigenic epitopes on the viral glycoproteins by host-identical N-glycans are different strategies for persistent virus infections. 相似文献
109.
110.
Burster T Beck A Tolosa E Schnorrer P Weissert R Reich M Kraus M Kalbacher H Häring HU Weber E Overkleeft H Driessen C 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(9):5940-5949
Dendritic cells (DC) initiate immunity and maintain tolerance. Although in vitro-generated DC, usually derived from peripheral blood monocytes (MO-DC), serve as prototype DC to analyze the biology and biochemistry of DC, phenotypically distinct primary types of DC, including CD1c-DC, are present in peripheral blood (PB-DC). The composition of lysosomal proteases in PB-DC and the way their MHC class II-associated Ag-processing machinery handles a clinically relevant Ag are unknown. We show that CD1c-DC lack significant amounts of active cathepsins (Cat) S, L, and B as well as the asparagine-specific endopeptidase, the major enzymes believed to mediate MHC class II-associated Ag processing. However, at a functional level, lysosomal extracts from CD1c-DC processed the multiple sclerosis-associated autoantigens myelin basic protein and myelin oligodendrocyte glycoprotein in vitro more effectively than MO-DC. Although processing was dominated by CatS, CatD, and asparagine-specific endopeptidase in MO-DC, it was dominated by CatG in CD1c-DC. Thus, human MO-DC and PB-DC significantly differ with respect to their repertoire of active endocytic proteases, so that both proteolytic machineries process a given autoantigen via different proteolytic pathways. 相似文献