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31.
A rapid and sensitive method for detecting and typing human papillomaviruses (HPVs) in cell scrapings is presented. DNA from scrapings is extracted and bound to nitrocellulose filters (Slot-Blot). By DNA-DNA hybridization with specific 32P-labelled HPV-probes (types 6/11 or 16/18) the patient's DNA is then analyzed for the presence of, and for the type of, HPV DNA sequences. A parallel hybridization with a human repetitive element (Alu sequence) allows quantitation of the different hybridization results. Experiments with HeLa cell DNA show that as little as 10(4) HPV sequences can be detected and typed specifically with this test. Evaluation of this test is completed within 6 to 7 days after cell collection. This Slot-Blot method was used to analyse 1330 specimens taken at the Bernese Dysplasia Outpatient Clinic. The results reveal a very high percentage (90%) of HPV-positive cases in the patient group examined.  相似文献   
32.
Sensorineural hearing loss (SNHL) is one of the most common congenital disorders in humans, afflicting one in every thousand newborns. The majority is of heritable origin and can be divided in syndromic and nonsyndromic forms. Knowledge of the expression profile of affected genes in the human fetal cochlea is limited, and as many of the gene mutations causing SNHL likely affect the stria vascularis or cochlear potassium homeostasis (both essential to hearing), a better insight into the embryological development of this organ is needed to understand SNHL etiologies. We present an investigation on the development of the stria vascularis in the human fetal cochlea between 9 and 18 weeks of gestation (W9–W18) and show the cochlear expression dynamics of key potassium‐regulating proteins. At W12, MITF+/SOX10+/KIT+ neural‐crest‐derived melanocytes migrated into the cochlea and penetrated the basement membrane of the lateral wall epithelium, developing into the intermediate cells of the stria vascularis. These melanocytes tightly integrated with Na+/K+‐ATPase‐positive marginal cells, which started to express KCNQ1 in their apical membrane at W16. At W18, KCNJ10 and gap junction proteins GJB2/CX26 and GJB6/CX30 were expressed in the cells in the outer sulcus, but not in the spiral ligament. Finally, we investigated GJA1/CX43 and GJE1/CX23 expression, and suggest that GJE1 presents a potential new SNHL associated locus. Our study helps to better understand human cochlear development, provides more insight into multiple forms of hereditary SNHL, and suggests that human hearing does not commence before the third trimester of pregnancy. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 75: 1219–1240, 2015  相似文献   
33.
The adult human cochlea contains various types of peripheral glial cells that envelop or myelinate the three different domains of the spiral ganglion neurons: the central processes in the cochlear nerve, the cell bodies in the spiral ganglia, and the peripheral processes in the osseous spiral lamina. Little is known about the distribution, lineage separation and maturation of these peripheral glial cells in the human fetal cochlea. In the current study, we observed peripheral glial cells expressing SOX10, SOX9 and S100B as early as 9 weeks of gestation (W9) in all three neuronal domains. We propose that these cells are the common precursor to both mature Schwann cells and satellite glial cells. Additionally, the peripheral glial cells located along the peripheral processes expressed NGFR, indicating a phenotype distinct from the peripheral glial cells located along the central processes. From W12, the spiral ganglion was gradually populated by satellite glial cells in a spatiotemporal gradient. In the cochlear nerve, radial sorting was accomplished by W22 and myelination started prior to myelination of the peripheral processes. The developmental dynamics of the peripheral glial cells in the human fetal cochlea is in support of a neural crest origin. Our study provides the first overview of the distribution and maturation of peripheral glial cells in the human fetal cochlea from W9 to W22.  相似文献   
34.
Visual interest in pictorial art during an aesthetic experience   总被引:1,自引:0,他引:1  
Two experiments were performed during which adults untrained in the visual arts were shown digital versions of eight paintings by renowned artists. In Experiment 1 participants' written reactions following a single 100 ms glance at each work were found to overwhelmingly reflect an initial holistic impression (i.e. gist) of the structural arrangement and semantic meaning of the paintings. In the second experiment participants' eye movements and verbal reactions were recorded as they evaluated each reproduction for pleasingness. Analyses reveal the relationships between the content and structural organization of the art stimuli and the way viewers select, process and think about information contained in paintings across the time course of an aesthetic experience. The results are interpreted in terms of an information-processing stage model of visual aesthetics according to which perceptual-cognitive processing of an art stimulus begins with the rapid generation of a gist reaction followed by scrutiny of pictorial features directed in a top-down fashion by cognitively-based evaluative processes.  相似文献   
35.
Immunogenic cell death induced by cytotoxic compounds contributes to the success of selected chemotherapies by eliciting a protective anticancer immune response, which is mediated by CD4+ and CD8+ T cells producing interferon-γ. In many instances, cancer progression is associated with high titers of tumor-specific antibodies, which become detectable in the serum, but whose functional relevance is elusive. Here, we explored the role of humoral immune responses in the anticancer efficacy of anthracyclines. Chemotherapy reduced the number of tumor-infiltrating B cells, and failed to promote humoral responses against immunodominant tumor antigens. Although anthracycline-based anticancer chemotherapies failed in T cell-deficient mice, they successfully reduced the growth of cancers developing in mice lacking B lymphocytes (due to the injection of a B-cell-depleting anti-CD20 antibody), immunoglobulins (Igs) or Ig receptors (Fc receptor) due to genetic manipulations. These results suggest that the humoral arm of antitumor immunity is dispensable for the immune-dependent therapeutic effect of anthracyclines against mouse sarcoma. In addition, we show here that the titers of IgA and IgG antibodies directed against an autoantigen appearing at the cell surface of tumor cells post chemotherapy (calreticulin, CRT) did not significantly increase in patients treated with anthracyclines, and that anti-CRT antibodies had no prognostic or predictive significance. Collectively, our data indicate that humoral anticancer immune responses differ from cellular responses in, thus far, that they do not contribute to the success of anthracycline-mediated anticancer therapies in human breast cancers and mouse sarcomas.  相似文献   
36.
37.
An HPLC assay with tandem mass spectrometric detection in the positive-ion Turbo-Ion-Spray (TISP) mode for the fast and sensitive determination of perifosine ((I), D-21266) in human plasma was developed, utilising the structural analogue, miltefosine ((II), D-18506), as internal standard. Automated solid-phase extraction of diluted plasma samples, based on 250-μl plasma aliquots, at pH 6.5, allowed a reliable quantification of perifosine down to 4 ng/ml. Injection of 200 μl of plasma extracts onto a 100×3 mm normal-phase analytical column at a flow-rate of 0.5 ml/min provided retention-times of 2.4 and 2.1 min for perifosine (I) and the internal standard (II), respectively. The standard curves were linear from 4 to 2000 ng/ml using weighted linear regression analysis (1/Y2). The inter-assay and intra-assay accuracies for the calibration standards were within +0.9% and −0.2%, exhibiting precisions (C.V.) of ±6.5 and ±7.3%, respectively. Up to 100 unknowns may be analysed each 24 h per analyst.  相似文献   
38.
ATP-binding cassette (ABC) transporters are integral membrane proteins that move diverse substrates across cellular membranes. ABC importers catalyse the uptake of essential nutrients from the environment, whereas ABC exporters facilitate the extrusion of various compounds, including drugs and antibiotics, from the cytoplasm. How ABC transporters couple ATP hydrolysis to the transport reaction has long remained unclear. The recent crystal structures of four complete ABC transporters suggest that a key step of the molecular mechanism is conserved in importers and exporters. Whereas binding of ATP promotes an outward-facing conformation, the release of the hydrolysis products ADP and phosphate promotes an inward-facing conformation. This basic scheme can in principle explain ATP-driven drug export and binding protein-dependent nutrient uptake.  相似文献   
39.
40.
Uptake of 4-toluene sulfonate by Comamonas testosteroni T-2.   总被引:7,自引:5,他引:2       下载免费PDF全文
The mechanism of transport of the xenobiotic 4-toluene sulfonate (TS) in Comamonas testosteroni T-2 was investigated. Rapid uptake of TS was observed only in cells grown with TS or 4-methylbenzoate as a carbon and energy source. Initial uptake rates under aerobic conditions showed substrate saturation kinetics, with an apparent affinity constant (Kt) of 88 microM and a maximal velocity (Vmax) of 26.5 nmol/min/mg of protein. Uptake of TS was inhibited completely by uncouplers and only marginally by ATPase inhibitors and the phosphate analogs arsenate and vanadate. TS uptake was also studied under anaerobic conditions, which prevented intracellular TS metabolism. TS was accumulated under anaerobic conditions in TS-grown cells upon imposition of an artificial transmembrane pH gradient (delta pH, inside alkaline). Uptake of TS was inhibited by structurally related methylated and chlorinated benzenesulfonates and benzoates. The results provide evidence that the first step in the degradation of TS by C. testosteroni T-2 is uptake by an inducible secondary proton symport system.  相似文献   
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