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71.
The syndrome of pure gonadal dysgenesis (PGD) cannot always easily be distinguished from other disorders of gonadal development. Relations are evident with Turner's syndrome, females with hypoplastic ovaries, male pseudohermaphroditism, mixed gonadal dysgenesis and the vanishing testes syndrome. The case is reported of a 40 year old female with primary amenorrhea, alopecia, eunuchoid features, XY karyotype with normal breast development and sexual hair after estrogen therapy. On laparotomy streak ovaries were found at ovarian site. Pathohistological examination revealed on the left side wolffian duct remnants such as ductuli deferentes and epididymis besides sparse Leydig-(hilus-)cells and on the right side only a rudimentary fallopian tube with subendothelial accumulation of hyperplastic Leydig-(hilus-)cells. Serum-testosterone elevation above the normal female range (630 ng/dl) persisted following gonadectomy (151 ng/dl). Ectopic Leydig-(hilus-)cells were regarded responsible for the continuing testosterone production. The present case lies on borderline between PGD and mixed gonadal dysgenesis because remnants of wolffian duct derivatives suggest unilateral fetal testicular activity; classification as PGD however was justified in purely female body features and lacking evidence of testicular tissue. 相似文献
72.
73.
Interstitial Cajal-like cells in human gallbladder 总被引:6,自引:0,他引:6
We describe here an interstitial Cajal-like cell type (ICLC) in human gallbladder, resembling the archetypal enteric interstitial
cells of Cajal. Gallbladder ICLC were demonstrated in fresh preparations (tissue cryosections) using methylene-blue, and fixed specimens in Epon semi-thin sections stained with toluidine blue or transmission electron microscopy (TEM). The positive diagnosis of gallbladder ICLC was further verified by immunohistochemistry: CD117/c-kit, CD34, and another 16 antigens: vimentin, desmin, nestin, α-smooth muscle actin, NK-1, S-100, PGP-9.5, tau protein,
chromogranin A, NSE, GFAP, CD1a, CD62-P, CD68, estrogen and progesterone receptors. Double immunostaining was performed for
CD117, CD34 and CD117 and nestin, respectively. In fresh specimens, the spatial density of gallbladder ICLC was 100–110 cells/mm2. ICLC mainly appeared beneath the epithelium and in muscularis (about 7%, and ∼5%, respectively). In toto, ICLC represent
in gallbladder ∼5.5% of subepithelial cells. TEM showed that diagnostic criteria were fulfilled by ICLC. Moreover, TEM indicated
that the main ultrastructural distinctive feature for ICLC, the cell processes, develop into the characteristic shape at a
relatively early stage of development. It remains to be established if, in humans, ICLC are involved in gallbladder (dis)functions
(e.g. pace-making, secretion (auto-, juxta- and/or paracrine), intercellular signaling, or stone formation).
M. E. Hinescu and C. Ardeleanu contributed equally to this study. 相似文献
74.
MOTIVATION: Homology search finds similar segments between two biological sequences, such as DNA or protein sequences. The introduction of optimal spaced seeds in PatternHunter has increased both the sensitivity and the speed of homology search, and it has been adopted by many alignment programs such as BLAST. With the further improvement provided by multiple spaced seeds in PatternHunterII, Smith-Waterman sensitivity is approached at BLASTn speed. However, computing optimal multiple spaced seeds was proved to be NP-hard and current heuristic algorithms are all very slow (exponential). RESULTS: We give a simple algorithm which computes good multiple seeds in polynomial time. Due to a completely different approach, the difference with respect to the previous methods is dramatic. The multiple spaced seed of PatternHunterII, with 16 weight 11 seeds, was computed in 12 days. It takes us 17 s to find a better one. Our approach changes the way of looking at multiple spaced seeds. 相似文献
75.
Ornamental flowers commonly grown in urban gardens and parks can be of value to flower‐visiting insects. However, there is huge variation in the number of insects attracted among plant varieties. In this study, we quantified the insect attractiveness of 79 varieties in full bloom being grown in a public urban garden that is popular due to its beautiful flowers and other attractions. The results showed very clearly that most varieties (77%, n = 61) were either poorly attractive or completely unattractive to insect flower visitors. Several varieties (19%, n = 15) were moderately attractive, but very few (4%, n = 3) were highly attractive. Closer examination of Dahlia varieties showed that “open” flowered forms were approximately 20 times more attractive than “closed” flowered forms. These results strongly suggest that there is a great potential for making urban parks and gardens considerably more bee‐ and insect‐friendly by selecting appropriate varieties. 相似文献
76.
Codorean E Nichita C Albulescu L Răducan E Popescu ID Lonită AC Albulescu R 《Roumanian archives of microbiology and immunology》2010,69(1):13-19
There is an emerging trend in immunotoxicological studies to use the multiplex technologies for testing the safety and the efficacy of new pharmaceuticals by using cytokines profiling as biomarker. The Luminex 200 xMAP (multi-analyte profiling) technology provides simultaneous measurement of multiple cytokines in small sample volumes, expressing rapidly the differences between various test compounds. The aim is to develop and validate the Luminex 200 multiplex immunoassays by correlation with ELISA (enzyme-linked immunosorbent assays) for implementation in evaluating cytokine profiling in immunotoxicological studies in vitro. METHODS: Human peripheral whole blood from healthy subject diluted 1+4 with RPMI 1640 was cultured 48 hours in 28 experimental variants: control, in presence of mitogens, bioflavonoid extracts (from Crataegus monogyna and Echinacea purpurea) as cytoprotectors and with a toxic compound [Pb(NO3)2]), separately or variously combined. IL-1beta and IL-2 were comparatively performed by xMAP and ELISA immunoassays from the same sample to initialize validation of multiplex cytokine panel: IL-1beta, IL-2, IL-4, IL-6, IL-8, IL-10, TNF-alpha, IFN-gamma, usually performed by Luminex 200 system in our immunotoxicological studies. The results indicate similarly typed trends of cytokine values obtained by both methods, with comparable relative changes in presence of mitogens, bioflavonoids and toxic, respectively. Although xMAP absolute cytokine values were higher than ELISA values, the correlation between multiplexed assay and ELISA was good for IL-1beta and IL-2 with positive correlation coefficients near to 1. Conclusions. Quantitative differences between absolute values for IL-1beta and IL-2 obtained by xMAP and ELISA assays are found, but the relative values are comparable and the two methods keep similar trends in similar exposure conditions. The performance parameters of the xMAP assay and the good correlation coefficients with the "gold standard" ELISA recommend to validate the multiplex assay for analyzing cytokine profiles in immunotoxicological studies in vitro. 相似文献
77.
Homozygous WNT3 mutation causes tetra-amelia in a large consanguineous family 总被引:9,自引:0,他引:9 下载免费PDF全文
Niemann S Zhao C Pascu F Stahl U Aulepp U Niswander L Weber JL Müller U 《American journal of human genetics》2004,74(3):558-563
Tetra-amelia is a rare human genetic disorder characterized by complete absence of all four limbs and other anomalies. We studied a consanguineous family with four affected fetuses displaying autosomal recessive tetra-amelia and craniofacial and urogenital defects. By homozygosity mapping, the disease locus was assigned to chromosome 17q21, with a maximum multipoint LOD score of 2.9 at markers D17S931, D17S1785, D17SS1827, and D17S1868. Further fine mapping defined a critical interval of approximately 8.9 Mb between D17S1299 and D17S797. We identified a homozygous nonsense mutation (Q83X) in the WNT3 gene in affected fetuses of the family. WNT3, a human homologue of the Drosophila wingless gene, encodes a member of the WNT family known to play key roles in embryonic development. The Q83X mutation truncates WNT3 at its amino terminus, suggesting that loss of function is the most likely cause of the disorder. Our findings contrast with the observation of early lethality in mice homozygous for null alleles of Wnt3. To our knowledge, this is the first report of a mutation in a WNT gene associated with a Mendelian disorder. The identification of a WNT3 mutation in tetra-amelia indicates that WNT3 is required at the earliest stages of human limb formation and for craniofacial and urogenital development. 相似文献
78.
It is widely accepted that the binding constant of a receptor and ligand can be written as a two-body integral involving the interaction energy of the receptor and the ligand. Interestingly, however, three different theories of binding in the literature dictate three distinct integrals. The present study uses theory, as well as simulations of binding experiments, to test the validity of the three integrals. When binding is measured by a signal that detects the ligand in the binding site, the most accurate results are obtained by an integral of the Boltzmann factor, where the bound complex is defined in terms of an exclusive binding region. A novel prediction of this approach, that expanding a ligand can increase its binding constant, is borne out by the simulations. The simulations also show that abnormal binding isotherms can be obtained when the region over which the signal is detected deviates markedly from the exclusion zone. Interestingly, the binding constant measured by equilibrium dialysis, rather than by monitoring a localized signal, can yield a binding constant that differs from that obtained from a signal measurement, and that is matched best by the integral of the Mayer factor. 相似文献
79.
Cyclins E1 and E2 are required for endoreplication in placental trophoblast giant cells 总被引:3,自引:0,他引:3
In mammalian cells, cyclin E-CDK2 complexes are activated in the late G1 phase of the cell cycle and are believed to have an essential role in promoting S-phase entry. We have targeted the murine genes CCNE1 and CCNE2, encoding cyclins E1 and E2. Whereas single knockout mice were viable, double knockout embryos died around midgestation. Strikingly, however, these embryos showed no overt defects in cell proliferation. Instead, we observed developmental phenotypes consistent with placental dysfunction. Mutant placentas had an overall normal structure, but the nuclei of trophoblast giant cells, which normally undergo endoreplication and reach elevated ploidies, showed a marked reduction in DNA content. We derived trophoblast stem cells from double knockout E3.5 blastocysts. These cells retained the ability to differentiate into giant cells in vitro, but were unable to undergo multiple rounds of DNA synthesis, demonstrating that the lack of endoreplication was a cell-autonomous defect. Thus, during embryonic development, the needs for E-type cyclins can be overcome in mitotic cycles but not in endoreplicating cells. 相似文献
80.
Lucian J. Cuprak Howard M. Berman 《In vitro cellular & developmental biology. Plant》1981,17(7):570-576
Summary Y-1 cells were passaged weekly for 6 wk in MACT IV medium without a period of adaptation to this basal medium that requires
1% dialyzed fetal bovine serum as a supplement. The steroid pathway and chromosome number, reported earlier for this cell
line under culture conditions that used much higher concentrations of nondialyzed sera, remained stable despite dialysis and
reduction of the fetal bovine serum to 1%.
Mass spectral analyses were carried out at the Mass Spectrometric Facility for Biomedical Research, Department of Biochemistry,
Faculty of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA, supported by NIH Grant RR-00273. This research was
supported by the Medical Research Service of the Veterans Administration. 相似文献