排序方式: 共有71条查询结果,搜索用时 15 毫秒
1.
Heterogeneity of epithelial cells in the human thymus 总被引:9,自引:0,他引:9
Frank P. van de Wijngaert Marion D. Kendall Henk-Jan Schuurman Ph.D. Loek H. P. M. Rademakers Louis Kater 《Cell and tissue research》1984,237(2):227-237
Summary To evaluate interrelationships among epithelial cells, and between morphology and function in the microenvironment, we studied the ultrastructural morphology of epithelial cells in sections of human thymus from donors aged 2 months to 31 years. Six types of epithelial cells were observed: subcapsular-perivascular (type 1); pale (type 2); intermediate (type 3); dark (type 4); undifferentiated (type 5); and large-medullary (type 6). Cells of types 2, 3 and 4 were found throughout the organ. The type-2 to -4 epithelial cells may represent various stages in a differentiation process. In this, type-2 cells are very active and type-4 cells are possibly degenerating elements. Type-4 cells can also contribute to Hassall's corpuscles. Type-5 cells were located mainly in the cortico-medullary region and showed the morphological characteristics of undifferentiated elements. Type-6 cells were located exclusively in the medulla and displayed characteristics of cellular activity. Small Hassall's corpuscles consisted of type-6 epithelial cells; in larger corpuscles many nuclei of type-6 cells were found. Cells of types 2 and 6 contained tubular structures (diameter approximately 20 nm).Concerning the function of thymus epithelial cells, the features associated with protein synthesis observed in cellular types 2 and 6 make them likely candidates for humoral factor-producing and/or secreting elements. In addition, type-2 and -3 cells in the cortex appear to contribute to a special pattern of epithelium-lymphocyte interaction (thymic nurse cells), as demonstrated by the intracytoplasmic location of lymphocytes in the epithelial cells. The various steps in intrathymic T-cell maturation occur at locations in a microenvironment composed of morphologically distinct epithelial cells. 相似文献
2.
André B. P. van Kuilenburg Heinz-Josef Klumpen Anneke M. Westermann Lida Zoetekouw Piet J. M. Bakker Henk-Jan Guchelaar 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):726-732
Dihydropyrimidine dehydrogenase (DPD) plays a pivotal role in the metabolism of 5-fluorouracil (5FU). In patients treated with capecitabine or 5FU combined with other chemotherapeutic drugs, DPD activity in peripheral blood mononuclear cells was increased in patients experiencing grade I/II neutropenia. In contrast, decreased DPD activity proved to be associated with grade I/II dermatological toxicity, including hand-foot syndrome. Thus, patients with a low-normal or high-normal DPD activity proved to be at risk of developing mild toxicity upon treatment with 5FU-based chemotherapy, demonstrating the important role of DPD in the etiology of toxicity associated with 5FU and the catabolites of 5FU. 相似文献
3.
Shaimaa Al-Janabi Henk-Jan van Slooten Mike Visser Tjeerd van der Ploeg Paul J. van Diest Mehdi Jiwa 《PloS one》2013,8(12)
Introduction
Mitotic Activity Index (MAI) is an important independent prognostic factor and an integral part of the breast cancer grading system. Thus, correct estimation of this prognostically relevant feature is essential for guiding treatment decision and assessing patient prognosis.The aim of this study was to validate the use of high resolution Whole Slide Images (WSI) in estimating MAI in breast cancer specimens.Methods
MAI was evaluated in 100 consecutive breast cancer specimens by three observers on two occasions, microscopically and on WSI with a wash out period of 4 months. MAI was also translated to mitotic scores as in grading. Inter- and intra-observer agreement between microscopic and digital MAI counts and scores was measured.Results
Almost perfect inter-observer agreements were obtained from counting MAI using a conventional microscope (intra-class correlation coefficient (ICCC) 0.879) as well as on WSI (ICCC 0.924). K coefficients reflected good inter-observer agreements among observers'' microscopic mitotic scores (average kappa 0.642). Comparable results were also observed among digital mitotic scores (average kappa 0.635). There was strong to perfect intra-observer agreements between MAI counts and mitotic scores for the two diagnostic modalities (ICCC 0.716–0.863, kappa 0.506–0.617). There were no significant differences in mitotic scores using both diagnostic modalities.Conclusion
Scoring mitoses using WSI in breast cancer seems to be just as reliable and reproducible as when using a microscope. Further development of software and image quality will definitely encourage the use of WSI in routine pathology practice. 相似文献4.
Yang Zhang Eugenio Butelli Rosalba De Stefano Henk-jan Schoonbeek Andreas Magusin Chiara Pagliarani Nikolaus Wellner Lionel Hill Diego Orzaez Antonio Granell Jonathan D.G. Jones Cathie Martin 《Current biology : CB》2013,23(12):1094-1100
- Download : Download high-res image (182KB)
- Download : Download full-size image
5.
Porcine endogenous retrovirus transmission characteristics of galactose alpha1-3 galactose-deficient pig cells
下载免费PDF全文
![点击此处可从《Journal of virology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Quinn G Wood JC Ryan DJ Suling KM Moran KM Kolber-Simonds DL Greenstein JL Schuurman HJ Hawley RJ Patience C 《Journal of virology》2004,78(11):5805-5811
Galactose alpha1-3 galactose (Gal) trisaccharides are present on the surface of wild-type pig cells, as well as on viruses particles produced from such cells. The recognition of Gal sugars by natural anti-Gal antibodies (NAb) in human and Old World primate serum can cause the lysis of the particles via complement-dependent mechanisms and has therefore been proposed as an important antiviral mechanism. Recently, pigs have been generated that possess disrupted galactosyl-transferase (GGTA1) genes. The cells of these pigs do not express Gal sugars on their surface, i.e., are Gal null. Concerns have been raised that the risk of virus transmission from such pigs may be increased due to the absence of the Gal sugars. We investigated the sensitivity of porcine endogenous retrovirus (PERV) produced from Gal-null and Gal-positive pig cells to inactivation by purified NAb and human serum. PERV produced in Gal-null pig cells was resistant to inactivation by either NAb or human serum. In contrast, although Gal-positive PERV particles were sensitive to inactivation by NAb and human serum, they required markedly higher concentrations of NAb for inactivation compared to the Gal-positive cells from which they were produced. Complete inactivation of Gal-positive PERV particles was not achievable despite the use of high levels of NAb, indicating that NAb-mediated inactivation of cell-free PERV particles is an inefficient process. 相似文献
6.
7.
Visch HJ Koopman WJ Leusink A van Emst-de Vries SE van den Heuvel LW Willems PH Smeitink JA 《Biochimica et biophysica acta》2006,1762(1):115-123
Although a large number of mutations causing malfunction of complex I (NADH:ubiquinone oxidoreductase) of the OXPHOS system is now known, their cell biological consequences remain obscure. We previously showed that the bradykinin (Bk)-induced increase in mitochondrial [ATP] ([ATP](M)) is significantly reduced in primary skin fibroblasts from a patient with an isolated complex I deficiency. The present work addresses the mechanism(s) underlying this impaired response. Luminometry of fibroblasts from 6 healthy subjects and 14 genetically characterized patients expressing mitochondria targeted luciferase revealed that the Bk-induced increase in [ATP](M) was significantly, but to a variable degree, decreased in 10 patients. The same variation was observed for the increases in mitochondrial [Ca(2+)] ([Ca(2+)](M)), measured with mitochondria targeted aequorin, and cytosolic [Ca(2+)] ([Ca(2+)](C)), measured with fura-2, and for the Ca(2+) content of the endoplasmic reticulum (ER), calculated from the increase in [Ca(2+)](C) evoked by thapsigargin, an inhibitor of the ER Ca(2+) ATPase. Regression analysis revealed that the increase in [ATP](M) was directly proportional to the increases in [Ca(2+)](C) and [Ca(2+)](M) and to the ER Ca(2+) content. Our findings provide evidence that a pathological reduction in ER Ca(2+) content is the direct cause of the impaired Bk-induced increase in [ATP](M) in human complex I deficiency. 相似文献
8.
9.
van Kuilenburg AB Klumpen HJ Westermann AM Zoetekouw L Bakker PJ Guchelaar HJ Richel DJ 《Nucleosides, nucleotides & nucleic acids》2008,27(6):726-732
Dihydropyrimidine dehydrogenase (DPD) plays a pivotal role in the metabolism of 5-fluorouracil (5FU). In patients treated with capecitabine or 5FU combined with other chemotherapeutic drugs, DPD activity in peripheral blood mononuclear cells was increased in patients experiencing grade I/II neutropenia. In contrast, decreased DPD activity proved to be associated with grade I/II dermatological toxicity, including hand-foot syndrome. Thus, patients with a low-normal or high-normal DPD activity proved to be at risk of developing mild toxicity upon treatment with 5FU-based chemotherapy, demonstrating the important role of DPD in the etiology of toxicity associated with 5FU and the catabolites of 5FU. 相似文献
10.
Fabrizio de Mattia Caroline Gubser Michiel M.T. van Dommelen Henk-Jan Visch Felix Distelmaier Antonio Postigo Tomas Luyten Jan B. Parys Humbert de Smedt Geoffey L. Smith Peter H.G.M. Willems Frank J.M. van Kuppeveld 《Molecular biology of the cell》2009,20(16):3638-3645
Golgi antiapoptotic protein (GAAP) is a novel regulator of cell death that is highly conserved in eukaryotes and present in some poxviruses, but its molecular mechanism is unknown. Given that alterations in intracellular Ca2+ homeostasis play an important role in determining cell sensitivity to apoptosis, we investigated if GAAP affected Ca2+ signaling. Overexpression of human (h)-GAAP suppressed staurosporine-induced, capacitative Ca2+ influx from the extracellular space. In addition, it reduced histamine-induced Ca2+ release from intracellular stores through inositol trisphosphate receptors. h-GAAP not only decreased the magnitude of the histamine-induced Ca2+ fluxes from stores to cytosol and mitochondrial matrices, but it also reduced the induction and frequency of oscillatory changes in cytosolic Ca2+. Overexpression of h-GAAP lowered the Ca2+ content of the intracellular stores and decreased the efficacy of IP3, providing possible explanations for the observed results. Opposite effects were obtained when h-GAAP was knocked down by siRNA. Thus, our data demonstrate that h-GAAP modulates intracellular Ca2+ fluxes induced by both physiological and apoptotic stimuli. 相似文献