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991.
Hyperimmunized patients tend to accumulate on renal transplant waiting lists because their high level of sensitization leads to positive crossmatches with almost all potential organ donors. The origins of sensitization and the different efforts made to find cross-match negative donors for these patients are discussed. Special emphasis is given to a local strategy based on the determination of HLA-A and -B mismatches, against which the patient did not form allo-antibodies, the so-called acceptable mismatches. Kidney donor selection is based on compatibility with the patient's own HLA-antigens in combination with the acceptable HLA-A and -B antigens, and can be operated from a central organ-sharing office. The acceptable HLA mismatches are often identical with or include the non-inherited HLA class I antigens of the mother (non-inherited maternal antigens: NIMA). 相似文献
992.
The clinical history and subsequent progress of a child with an interstitial deletion in the short arm of chromosome 6 is described. This abnormality coupled with a reduced Hageman factor (Factor XII) led to an earlier publication which suggested that this gene was localized to the breakpoint region involved. A review of similar phenotypes from the literature is presented. 相似文献
993.
A. van Belkum R. Bax G. Prevost 《European journal of clinical microbiology & infectious diseases》1994,13(5):420-424
Twenty-six methicillin-resistantStaphylococcus aureus strains were genetically differentiated by interrepeat PCR and the results compared with those of ribotyping, pulsed-field gel electrophoresis (PFGE) and random amplified polymorphic DNA analysis obtained in a previous study for the same strains. The comparison showed that the PCR-mediated assays were as discriminatory as PFGE, whereas ribotyping was the least powerful genotyping method. Due to the ease of performance, PCR fingerprinting may become the method of choice for establishing clonal relationships amongStaphylococcus aureus isolates. 相似文献
994.
R. B. Bajnath N. van den Berghe H. R. De Jonge J. A. Groot 《Pflügers Archiv : European journal of physiology》1993,425(1-2):90-99
The differentiated clone 19A of the HT-29 human colon carcinoma cell line was used as a model to study the intracellular electrophysiological effects of interaction of the cAMP, the protein kinase C (PKC) and the Ca2+ pathways, (a) A synergistic effect between ionomycin and forskolin was observed. From intracellular responses it was concluded that the synergistic effect is caused by activation of an apical Cl– conductance by protein kinase A and a basolateral K+ conductance by Ca2+. (b) A transient synergistic effect of ionomycin and the phorbol ester phorbol dibutyrate (PDB) was found. The decrease of the response appeared to be due to PKC-dependent inactivation of the basolateral K+ conductance. The synergism is caused by PKC-dependent increase of the apical Cl– conductance and Ca2+-dependent increase of the basolateral K+ conductance. (c) The effects of carbachol and PDB were not fully additive presumably because of their convergence on PKC activation, (d) Forskolin and PDB, when added in this order, had a less than additive effect. Results of cell-attached patch-clamp studies, presented in the accompanying paper, showed a synergistic effect of forskolin and PDB on non-rectifying small-conductance Cl– channels. Assuming that these channels are involved in the transepithelial responses it is suggested that forskolin and PDB induce a modulatory, synergistic increase of the apical Cl– conductance when both pathways are activated simultaneously. (e) The HT-29cl.19A cells differ from T84 cells in that the latter did not respond with an increase of the short-circuit current to addition of phorbol ester. This may be due to a very low expression of PKC. 相似文献
995.
F. A. M. Jonkman M. J. M. C. Thoolen B. Wilffert A. de Jonge P. B. M. W. M. Timmermans P. A. van Zwieten 《Pflügers Archiv : European journal of physiology》1984,402(4):341-344
The influence of a chronically elevated total plasma calcium concentration on blood pressure and heart rate was investigated in conscious normotensive rats. The plasma calcium concentration was elevated by continuous subcutaneous infusion with parathormone (PTH) after parathyreoidectomy, and by oral treatment with vitamin D3. In both groups an elevated blood pressure was observed at the 1st day of treatment only. Blood pressure was returned to pretreatment values from the second day of treatments onaards. No significant changes in heart rate, due to hypercalcaemia, were observed. In hypercalcaemic rats, the calcium entry inhibitor nifedipine proved more potent in reducing blood pressure than in normocalcaemic control animals. Hydralazine was equipotent in reducing blood pressure in both groups. It is suggested, that the vasoconstrictor effects of a chronically elevated total plasma calcium concentration in conscious rats does not obviously result in a chronically elevated blood pressure, but rather in an enhanced sensitivity of the blood pressure towards calcium entry blockade. 相似文献
996.
Do food antigens play a role in the pathogenesis of some cases of human glomerulonephritis? 下载免费PDF全文
F J van der Woude P J Hoedemaeker M van der Giessen P A de Graeff J de Monchy T H The G K van der Hem 《Clinical and experimental immunology》1983,51(3):587-594
Circulating immune complexes after a test meal were measured with three methods (PEG precipitation, Clq-ELISA and the indirect granulocyte phagocytosis test) in 10 controls, two symptomless persons with selective IgA deficiency and 14 patients with various types of glomerulonephritis, of which two patients (with idiopathic membranous glomerulopathy and local focal glomerulonephritis) also had selective IgA deficiency. The PEG and Clq-ELISA test did not show significant differences between the groups. In the two symptomless persons with selective IgA deficiency and in the patient with local focal glomerulonephritis and selective IgA deficiency the indirect granulocyte phagocytosis test (IGFT) showed a reproducible increase in IgG, IgM and complement containing immune complexes. In the last patient multiple food antigens were probably responsible for this phenomenon, a rapid amelioration of kidney function could be induced three times by giving an antigen free diet. 相似文献
997.
998.
Hans A. C. Alkemade Ivonne M. J. J. van Vlijmen-Willems Urbaan J. G. M. van Haelst Peter C. M. van de Kerkhof Joost Schalkwijk 《The Journal of pathology》1994,174(2):121-129
Skin-derived antileukoproteinase (SKALP), also known as elafin, is a strong and specific inhibitor of elastase and proteinase 3. SKALP is not present in normal epidermis, but is expressed by epidermal keratinocytes under hyperproliferative conditions such as psoriasis, wound healing, and in cell culture. In human epidermal tumours, SKALP is differentially expressed and restricted to tumours with distinct squamous differentiation. We have studied the presence of both SKALP and one of its known target enzymes, leukocyte elastase, in 41 squamous cell carcinomas of the skin. SKALP expression correlated with the degree of differentiation: strong expression was seen in well-differentiated cells and expression was absent in poorly differentiated tumour cells. Most of the squamous cell carcinomas showed elastase-positive cells in the tumour stroma and also within the tumour cell nests. SKALP may interfere with the proteoloytic activity of infiltrating inflammatory cells or with hitherto unknown proteinases from the tumour cells. We hypothesize that in squamous cell carcinoma progressive loss of SKALP expression could facilitate tumour spread. 相似文献
999.
Pierre-Paul van Bogaert Johan S. Vereecke Edward E. Carmeliet 《Pflügers Archiv : European journal of physiology》1978,375(1):45-52
- Cardiac Purkinje fibers exposed to alkaline solutions (pH 8 to 9.5) show an increase in rate of diastolic depolarization, eventually resulting in induction of spontaneous activity or an increase of the spontaneous firing rate.
- The voltage-clamp analysis of the transmembrane currents in pH 9–9.5 shows: i) a shift in the depolarizing direction of the activation (s∞) and time constants (τ s ) curve of the \(i_{{\text{K}}_{\text{2}} }\) current, ii) a small increase in the maximal value of the fully activated \(i_{{\text{K}}_{\text{2}} }\) current, iii) no significant change of background current in the pacemaker region of membrane potentials.
- The effect of NH4Cl was studied as a means to vary intracellular pH. In the presence of Tris buffer the addition of 5 mM NH4Cl resulted in i) a shift in the depolarizing direction and a decrease in slope of the activation curve of the \(i_{{\text{K}}_{\text{2}} }\) current, ii) a shift in the depolarizing direction of the time-constants curve together with an increase in the maximum value of τ s , iii) an increase in the maximum value of the fully activated \(i_{{\text{K}}_{\text{2}} }\) current and a depolarizing shift of the reversal potential, similar to the effect of addition of Kc. In the presence of CO2?HCO3 buffer the addition of NH4Cl had no significant effect on the kinetics of the \(i_{{\text{K}}_{\text{2}} }\) current. Since intracellular pH is only affected by NH4Cl in the presence of Tris buffer, the results suggest that intracellular alkalinization is responsible for the change in \(i_{{\text{K}}_{\text{2}} }\) kinetics.
- Based on the findings with NH4Cl it is suggested that perfusion with Tris buffered alkaline solutions not only affects net negative surface charges on the outside but also and to a larger extent increases negative surface charges on the inside of the cell membrane.
1000.
Elevated plasma levels of the long pentraxin, pentraxin 3, in severe dengue virus infections 总被引:4,自引:0,他引:4
Mairuhu AT Peri G Setiati TE Hack CE Koraka P Soemantri A Osterhaus AD Brandjes DP van der Meer JW Mantovani A van Gorp EC 《Journal of medical virology》2005,76(4):547-552
C-reactive protein is one of the most widely used indicators of the response of acute-phase proteins. The measurement of C-reactive protein in dengue, however, is clinically not useful, because of marginally elevated levels and absent association with disease severity. The prototypic long pentraxin, pentraxin 3, is an acute phase protein that is structurally related but distinct from C-reactive protein which has proven to correlate with the severity of bacterial infection in critically ill patients. The potential involvement of pentraxin 3 in dengue and its aptitude to predict more severe disease or poor clinical outcome has not been studied previously. We therefore measured pentraxin 3 plasma levels in 44 dengue virus infected patients. Pentraxin 3 levels were strikingly higher when compared to C-reactive protein levels, with highest pentraxin 3 values observed in the first 7 days after the onset of symptoms. Median pentraxin 3 levels at admission and peak levels during follow up were higher in patients suffering from dengue shock syndrome (at admission: 119.3 ng/ml [interquartile range 61.8--188.7], peak values during follow up: 147.9 ng/ml [interquartile range 85.7--204.3]) compared to levels found in patients with dengue fever and dengue hemorrhagic fever (at admission: 59.0 ng/ml [interquartile range 28.6--100.3], P=0.040; peak values during follow up: 80.8 ng/ml [interquartile range 36.1--168.1], P=0.020). Our results indicate that pentraxin 3 seems to be a marker of infection better than C-reactive protein in dengue. The role of pentraxin 3 in the pathogenesis of dengue and its potential as an early prognostic indicator of disease severity needs further assessment. 相似文献