排序方式: 共有9条查询结果,搜索用时 31 毫秒
1
1.
Pericić M Lauc LB Klarić IM Rootsi S Janićijevic B Rudan I Terzić R Colak I Kvesić A Popović D Sijacki A Behluli I Dordevic D Efremovska L Bajec DD Stefanović BD Villems R Rudan P 《Molecular biology and evolution》2005,22(10):1964-1975
The extent and nature of southeastern Europe (SEE) paternal genetic contribution to the European genetic landscape were explored based on a high-resolution Y chromosome analysis involving 681 males from seven populations in the region. Paternal lineages present in SEE were compared with previously published data from 81 western Eurasian populations and 5,017 Y chromosome samples. The finding that five major haplogroups (E3b1, I1b* (xM26), J2, R1a, and R1b) comprise more than 70% of SEE total genetic variation is consistent with the typical European Y chromosome gene pool. However, distribution of major Y chromosomal lineages and estimated expansion signals clarify the specific role of this region in structuring of European, and particularly Slavic, paternal genetic heritage. Contemporary Slavic paternal gene pool, mostly characterized by the predominance of R1a and I1b* (xM26) and scarcity of E3b1 lineages, is a result of two major prehistoric gene flows with opposite directions: the post-Last Glacial Maximum R1a expansion from east to west, the Younger Dryas-Holocene I1b* (xM26) diffusion out of SEE in addition to subsequent R1a and I1b* (xM26) putative gene flows between eastern Europe and SEE, and a rather weak extent of E3b1 diffusion toward regions nowadays occupied by Slavic-speaking populations. 相似文献
2.
Terezija Hr?enjak Maja Popovi? Tamara Bo?i? Mira Grdisa Dorde Kobrehel Ljerka Tiška-Rudman 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1998,119(4):825-832
Biologically active glycolipoprotein complex (G-90) isolated from whole earthworm tissue extract shows anticoagulative and fibrinolytic activities. We isolated two tyrosine like serine peptidases with molecular masses of 34 kDa (P I) and 23 kDa (P II), respectively. P I peptidase is autocatalytically degraded to P II. Both peptidases exhibit fibrinolytic and anticoagulative activities. The activity of P I is much higher. P I in concentration of 105 ng ml−1 of plasma shortened the physiological time of fibrin clot lysis by 54% and completely inhibited blood clotting at a concentration of 103 ng ml−1 of venous blood. 相似文献
3.
An extracellular 1,4-α-d-glucan 6-α-d-glucosyltransferase [d-glucosyltransferase, 1,4-α-d-glucan:1,4-α-d-glucan(d-gluco 6-α-d-glucosyltransferase, EC 2.4.1.24] from Aspergillus niger R-27 has been purified and the kinetics of its proteolytic inactivation with subtilisin studied. The purified enzyme was shown to be homogeneous using disc polyacrylamide gel electrophoresis. It contained 16.0% mannose, 0.19% glucose and 2.95% 2-acetamido-2-deoxy-d-glucose. The characteristic feature of the proteolytic degradation of glucosyltransferase is rapid hydrolysis of ~12 peptide bonds per mol and the formation of an active intermediate product which is more resistant to further proteolysis, but is easily heat-inactivated. The isolation and some properties of glucosyltransferase are also described. 相似文献
4.
Chemical and physico-chemical properties as well as physiological functions of major mammalian ether-linked glycerolipids, including plasmalogens were reviewed. Their chemical structures were described and their effect on membrane fluidity and membrane fusion discussed. The recent generation of mouse models with ether lipid deficiency offered the possibility to study ether lipid and particularly plasmalogen functions in vivo. Ether lipid-deficient mice revealed severe phenotypic alterations, including arrest of spermatogenesis, development of cataract and defects in central nervous system myelination. In several cell culture systems lack of plasmalogens impaired intracellular cholesterol distribution affecting plasma membrane functions and structural changes of ER and Golgi cisternae. Based on these phenotypic anomalies that were accurately described conclusions were drawn on putative functions of plasmalogens. These functions were related to cell-cell or cell-extracellular matrix interactions, formation of lipid raft microdomains and intracellular cholesterol homeostasis. There are several human disorders, such as Zellweger syndrome, rhizomelic chondrodysplasia punctata, Alzheimer's disease, Down syndrome, and Niemann-Pick type C disease that are distinguished by altered tissue plasmalogen concentrations. The role plasmalogens might play in the pathology of these disorders is discussed. 相似文献
5.
Tobias B?uerle Dorde Komljenovic Martin R. Berger Wolfhard Semmler 《Journal of visualized experiments : JoVE》2012,(66)
Angiogenesis is an essential feature of cancer growth and metastasis formation. In bone
metastasis, angiogenic factors are pivotal for tumor cell proliferation in the bone marrow
cavity as well as for interaction of tumor and bone cells resulting in local bone
destruction. Our aim was to develop a model of experimental bone metastasis that allows
in vivo assessment of angiogenesis in skeletal lesions using
non-invasive imaging techniques.For this purpose, we injected 105 MDA-MB-231 human breast cancer cells into
the superficial epigastric artery, which precludes the growth of metastases in body areas
other than the respective hind leg1. Following 25-30 days after tumor cell
inoculation, site-specific bone metastases develop, restricted to the distal femur,
proximal tibia and proximal fibula1. Morphological and functional aspects of
angiogenesis can be investigated longitudinally in bone metastases using magnetic
resonance imaging (MRI), volumetric computed tomography (VCT) and ultrasound (US).MRI displays morphologic information on the soft tissue part of bone metastases that is
initially confined to the bone marrow cavity and subsequently exceeds cortical bone while
progressing. Using dynamic contrast-enhanced MRI (DCE-MRI) functional data including
regional blood volume, perfusion and vessel permeability can be obtained and
quantified2-4. Bone destruction is captured in high resolution using
morphological VCT imaging. Complementary to MRI findings, osteolytic lesions can be
located adjacent to sites of intramedullary tumor growth. After contrast agent
application, VCT angiography reveals the macrovessel architecture in bone metastases in
high resolution, and DCE-VCT enables insight in the microcirculation of these
lesions5,6. US is applicable to assess morphological and functional features
from skeletal lesions due to local osteolysis of cortical bone. Using B-mode and Doppler
techniques, structure and perfusion of the soft tissue metastases can be evaluated,
respectively. DCE-US allows for real-time imaging of vascularization in bone metastases
after injection of microbubbles7.In conclusion, in a model of site-specific breast cancer bone metastases multi-modal
imaging techniques including MRI, VCT and US offer complementary information on morphology
and functional parameters of angiogenesis in these skeletal lesions. 相似文献
6.
The antioxidant activity and contents of various polyphenol classes in the silks of fifteen maize hybrids with economic importance in Serbia were evaluated. Total polyphenols, tannins and proanthocyanidins were determined spectrophotometrically, after extraction of plant material with 70% aqueous acetone under sonication at room temperature. In addition, flavonoid content was determined. Antioxidant activity of aqueous acetone extracts was evaluated by FRAP assay. A positive linear correlation between antioxidant activity and contents of all investigated polyphenol classes was established. The highest antioxidant activity was observed in the extract of NS 640 hybrid, which had high levels of all polyphenol classes examined. Results suggested strongly that polyphenol content should be considered as an important feature of the herbal drug Maydis stigma. For that reason, the biological source of this herbal drug needs to be more precisely defined, as observed activities and polyphenol contents were greatly dependent on plant material source. 相似文献
7.
Raizman JE Komljenovic J Chang R Deng C Bedosky KM Rattan SG Cunnington RH Freed DH Dixon IM 《Journal of cellular physiology》2007,213(2):540-551
Cardiac ventricular myofibroblast motility, proliferation, and contraction contribute to post-myocardial infarct wound healing, infarct scar formation, and remodeling of the ventricle remote to the site of infarction. The Na+-Ca2+ exchanger (NCX1) is involved in altered calcium handling in cardiac myocytes during cardiac remodeling associated with heart failure, however, its role in cardiac myofibroblast cell function is unexplored. In this study we investigated the involvement of NCX1 as well as the role of non-selective-cation channels (NSCC) in cardiac myofibroblast cell function in vitro. Immunofluorescence and Western blots revealed that P1 cells upregulate alpha-smooth muscle actin (alphaSMA) and embryonic smooth muscle myosin heavy chain (SMemb) expression. NCX1 mRNA and proteins as well as Ca(v)1.2a protein are also expressed in P1 myofibroblasts. Myofibroblast motility in the presence of 50 ng/ml PDGF-BB was blocked with AG1296. Myofibroblast motility, contraction, and proliferation were sensitive to KB-R7943, a specific NCX1 reverse-mode inhibitor. In contrast, only proliferation and contraction, but not motility were sensitive to nifedipine, while gadolinium (NSCC blocker) was only associated with decreased motility. ML-7 treatment was associated with inhibition of the chemotactic response and contraction. Thus cardiac myofibroblast chemotaxis, contraction, and proliferation were sensitive to different pharmacologic treatments suggesting that regulation of transplasmalemmal calcium movements may be important in growth factor receptor-mediated processes. NCX1 may represent an important moiety in suppression of myofibroblast functions. 相似文献
8.
Dorde Kobrehel 《Biotechnology letters》1979,1(6):251-254
Summary A new procedure for the determination of glucosyltransferase (EC 2.4.1.24) activity in amyloglucosidase preparations has been developed. The procedure is based on the rapid separation of glucosyltransferase from amyloglucosidase on carboxymethyl bio-gel A. 相似文献
9.
Dorde Komljenovic Roger Sandhoff Andre Teigler Hans Heid Wilhelm W. Just Karin Gorgas 《Cell and tissue research》2009,337(2):281-299
One of the major roles of Sertoli cells is to establish the blood-testis (Sertoli cell) barrier (BTB), which is permanently
assembled and disassembled to accommodate the translocation of leptotene spermatocytes from the basal into the adluminal compartment
of the seminiferous epithelium and to guarantee completion of meiosis and spermiogenesis. Recently, we have demonstrated spermatogenesis
to be arrested before spermatid elongation in Gnpat-null mice with selective deficiency of ether lipids (ELs) whose functions are poorly understood. In this study, we have focused
on the spatio-temporal expression of several BTB tight-junctional proteins in the first wave of spermatogenesis to obtain
insights into the physiological role of ELs during BTB establishment and dynamics. Our data confirm the transient existence
of Russell’s intermediate or translocation compartment delineated by two separate claudin-3-positive luminal and basal tight
junctions and reveal that EL deficiency blocks BTB remodeling. This block is associated with (1) downregulation and mistargeting
of claudin-3 and (2) impaired BTB disassembly resulting in deficient sealing of the intermediate compartment as shown by increased
BTB permeability to biotin. These results suggest that ELs are essential for cyclic BTB dynamics ensuring the sluice mechanism
for leptotene translocation into the adluminal compartment.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
This work was supported by the German Research Foundation (grants Go 432/2-1, Ju 166/3-1, and Sa 172/1-1). 相似文献
1