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排序方式: 共有1137条查询结果,搜索用时 15 毫秒
1.
Donor interleukin-4 promoter gene polymorphism influences allograft rejection after heart transplantation. 总被引:3,自引:0,他引:3
Femke J Bijlsma Joyce vanKuik Marcel G J Tilanus Nicolaas deJonge Erik H Rozemuller Jan G van den Tweel Frits H J Gmelig-Meyling Roel A deWeger 《The Journal of heart and lung transplantation》2002,21(3):340-346
BACKGROUND: The cytokine interleukin-4 (IL-4) is secreted mainly by activated T lymphocytes and characterizes the T-helper 2 (Th2) sub-type. In transplantation Th2 cells are believed to induce graft tolerance. Previous studies revealed that patients with a relatively high frequency of IL-4 producing helper T lymphocytes (HTL) before heart transplantation (HTX) had no or less rejection episodes compared with patients with a low frequency of IL-4 producing HTL. Three single nucleotide polymorphisms (SNPs) have been identified in the promoter region of the IL-4 gene, which influence promoter strength. We investigated whether there was a correlation between SNP genotypes in the IL-4 promoter and heart failure, and rejection after HTX. METHODS: Seventy HTX patients, 61 donors, and 36 controls were genotyped for the 3 SNPs by sequencing. RESULTS: Of the SNPs at -285 and -81, only the C and A alleles, respectively, were found in this study. Both alleles were found for the -590 SNP. No relation between patient genotype of the SNP at -590 and heart failure and rejection was found. However, incidence of rejection was significantly lower in patients that received a donor heart with the T-positive genotype compared with patients that received a heart from a T-negative donor. Patients who had the T-negative genotype and received a heart from a T-positive donor, suffered significantly less from rejection than T-negative patients that received a T-negative donor heart. This was not significant in the T-positive patient group. CONCLUSIONS: This indicates that IL-4 production within the donor heart and by cells from the donor is important for reducing incidence of episodes of rejection. 相似文献
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Background In patients with vitiligo, sometimes the greatest part of the skin has already lost its melanocytes. The remaining pigmented patches can be removed by using strong bleaching creams, but many adverse events have been reported with this treatment. Anew depigmentation therapy could be treatment with a Ruby laser. Methods Before treatment, the patients filled out a questionnaire about their vitiligo history. Eight patients with remaining pigmentation of the arms, hands, and face were treated once with a Ruby laser. Patients were monitored for developing repigmentation during the 9 months after treatment. Results In patients with a positive Koebner phenomenon, a permanent state of depigmentation was reached after laser therapy. None of the treated patients showed severe side-effects. Conclusions Ruby laser treatment can be an effective, fast, and safe method for removing cosmetically disturbing remnants of normal pigmentation in vitiligo patients with a positive Koebner phenomenon. 相似文献
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Microvascular function in viable myocardium after chronic infarction does not influence fractional flow reserve measurements. 总被引:1,自引:0,他引:1
Koen M Marques Paul Knaapen Ronald Boellaard Adriaan A Lammertsma Nico Westerhof Frans C Visser 《Journal of nuclear medicine》2007,48(12):1987-1992
Fractional flow reserve (FFR) is an index of coronary stenosis severity. FFR is the ratio of hyperemic myocardial flow in the stenotic area to maximal flow in that same territory without stenosis and can be measured with a pressure wire. In patients with prior infarction, measuring FFR in infarct-related arteries may be different for 2 reasons: a smaller mass of viable myocardium depending on the stenotic infarct-related artery and greater microvascular resistance in the infarcted area than in the reference area. When microvascular resistance does not differ between the infarcted and the reference areas, FFR should equal relative flow reserve (RFR). RFR is the ratio of myocardial blood flow in the stenotic area to blood flow in a normally perfused reference area, at maximal hyperemia. H(2)(15)O PET measures myocardial flow within only the viable areas of an infarct and can be used to measure RFR. The present study assessed in patients with chronic myocardial infarction whether microvascular resistance in the infarct is different from that in the reference area. Therefore, the correlation between FFR and RFR using H(2)(15)O PET was studied. METHODS: In the catheterization laboratory, FFR was measured in the infarct-related artery and a reference coronary artery. The H(2)(15)O PET study and FFR measurements were performed on the same day in 22 patients. RESULTS: In 27 patients, the mean interval between the PET study and infarction was 3.3 y. Most patients had an anterior infarction, and the mean ejection fraction was 44%. The mean FFR and RFR values were 0.75 +/- 0.16 and 0.74 +/- 0.18, respectively. A significant correlation (r = 0.81; P < 0.0001) was found between FFR and RFR. The linear regression line was close to the line of identity. CONCLUSION: In patients with chronic myocardial infarction and a reduced ejection fraction, a good correlation was found between FFR measurements in the infarct-related artery and RFR. Because the linear regression line between FFR and RFR was close to the line of identity, one can conclude that microvascular resistance in the viable myocardium does not differ from that in the reference area. 相似文献
6.
Braakman R. Sipkema P. Westerhof N. 《Pflügers Archiv : European journal of physiology》1986,407(4):432-439
It has been reported that sodiumnitroprusside (SNP) decreases mean systemic pressure and simultaneously increases pressure pulse amplification towards the iliac periphery (Kenner and van Zwieten 1982). This unexpected finding was suggested to be due to a decrease in iliac peripheral resistance but an increase in iliac differential resistance. In order to investigate this apparent contradiction, the iliac periphery was hemodynamically isolated from the rest of the circulation and perfused with the dog's own blood by means of a pump. Perfusion pressure (P) and flow (F), femoral venous pressure (Pv), systemic pressure (Ps) and cardiac output (CO) were measured. Steady state pressure-flow relations of the isolated bed were obtained during control and during various i.v. infusion rates of SNP and adenosine (ADS) and were found to be straight (meanr=0.99). Their slope (P/F) was defined as differential resistance (Rd). Peripheral resistance (Rp) of the iliac bed was defined as Rp=(P-Pv)/F, calculated at the flow value where perfusion pressure equalled the prevailing systemic pressure. Total peripheral resistance (TPR) was defined as TPR=Ps/CO. The changes of Rd, Rp, Ps, CO and TPR with respect to control show that during low SNP infusion rates Rd and Rp were both increased while TPR was decreased. During all infusion rates of SNP CO did not change while Ps decreased. During low infusion rates of adenosine CO increased while Ps, Rd and Rp did not change and TPR decreased. During high infusion rates of ADS CO decreased again, Rd, Rp and Ps decreased, and TPR remained constant but at a decreased level.It is concluded that: (1) the suggestion of Kenner and van Zwieten is not supported, since SNP (as well as ADS) affects iliac peripheral and iliac differential resistance in a similar way; (2) SNP (as well as ADS) affects iliac peripheral resistance and total peripheral resistance in a differentiated way, and even in an opposite way during low infusion rates of SNP; (3) it is this opposite effect that explains the paradoxical observations of Kenner and van Zwieten; (4) for comparable reductions of TPR, CO is better maintained during infusion of SNP, while Ps is better maintained during infusion of ADS. 相似文献
7.
DNA-binding polarity of human replication protein A positions nucleases in nucleotide excision repair 总被引:15,自引:0,他引:15
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Wouter L. de Laat Esther Appeldoorn Kaoru Sugasawa Eric Weterings Nicolaas G.J. Jaspers Jan H.J. Hoeijmakers 《Genes & development》1998,12(16):2598-2609
The human single-stranded DNA-binding replication A protein (RPA) is involved in various DNA-processing events. By comparing the affinity of hRPA for artificial DNA hairpin structures with 3′- or 5′-protruding single-stranded arms, we found that hRPA binds ssDNA with a defined polarity; a strong ssDNA interaction domain of hRPA is positioned at the 5′ side of its binding region, a weak ssDNA-binding domain resides at the 3′ side. Polarity appears crucial for positioning of the excision repair nucleases XPG and ERCC1–XPF on the DNA. With the 3′-oriented side of hRPA facing a duplex ssDNA junction, hRPA interacts with and stimulates ERCC1–XPF, whereas the 5′-oriented side of hRPA at a DNA junction allows stable binding of XPG to hRPA. Our data pinpoint hRPA to the undamaged strand during nucleotide excision repair. Polarity of hRPA on ssDNA is likely to contribute to the directionality of other hRPA-dependent processes as well. 相似文献
8.
Evaluation of Hemagglutinin Protein-Specific Immunoglobulin M for Diagnosis of Measles by an Enzyme-Linked Immunosorbent Assay Based on Recombinant Protein Produced in a High-Efficiency Mammalian Expression System
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Fabienne B. Bouche Nicolaas H. C. Brons Sophie Houard Francois Schneider Claude P. Muller 《Journal of clinical microbiology》1998,36(12):3509-3513
Recombinant hemagglutinin (H) of the measles virus (MV) expressed in a mammalian high-expression system based on the Semliki Forest virus replicon was used in an enzyme-linked immunosorbent assay (ELISA) for the detection of specific immunoglobulin M (IgM) and IgG in patients with acute-phase measles. One hundred twelve serum specimens from 70 patients with measles were analyzed. Case definition was based on a commercial IgM ELISA that utilizes MV-infected cells (MV-ELISA) (Enzygnost; Behring Diagnostics); the clinical criteria of the Centers for Disease Control and Prevention (Atlanta, Ga.); and/or the increase in hemagglutinin test titers, neutralization test titers, and levels of MV-specific IgG whenever paired sera were available. The initial time courses of the IgM signal after the onset of rash are similar in the H- and MV-ELISAs. On days 0 to 19, both ELISAs detected IgM in 67 of 68 (98.5%) sera. Average maximal levels of IgM seem to persist, however, about 10 days longer in the MV-ELISA (up to day 25) than in the H-ELISA (day 15). From days 20 to 29 and 30 to 59, the H-ELISA detected only 64.3 (9 of 14) and 19.2% (5 of 26), respectively, of sera that were IgM positive by MV-ELISA. At least up to day 30, the performance of the H-ELISA seemed to be similar to that reported for commercial ELISAs based on whole MV. Our results demonstrate that MV H-specific IgM can be used to diagnose most measles cases from a single serum specimen collected within 19 days after the onset of rash and that the recombinant protein used in this study is suitable for this purpose. 相似文献
9.
Pieter Sipkema Ricky D. Latham Nicolaas Westerhof Bernard J. Rubal David M. Slife 《Annals of biomedical engineering》1990,18(5):491-503
A setup consisting of a high-performance hydraulic pump connected to the ascending part of an isolated aorta, including all
major distal branches, each loaded with calibrated artificial resistors, was developed. The system was used to study total
aortic compliance of the baboon as a function of mean aortic pressure (n=5). The aorta loaded with the resistors was mounted
in a custom-designed sink table, such that it was submersed in physiological saline maintained at 37°C. Mean distending pressure
in the entire aortic compliance from pressure and flow waves generated by the pump. Total aortic compliance as a function
of mean pressure was fitted with a logarithmic function: Ln (Compliance)=A+B * P. The value of A(±SE) was: 1.565±0.319 and
B: −0.020±0.003 (P<0.001). The results were compared with previously published results (also using the same three-element
Windkessel fit) obtained in three of the same animalsin vivo. Thein vivo data were A: 1.095±0.235 and B: −0.019±0.003.In vitro data had a significantly higher value of A thanin vivo (P=0.017), implying a significantly higher aortic compliancein vitro thanin vivo.
Occlusion of the proximal descending aorta was performed at a low distending pressure (55 mm Hg) to determine the proximal
complicance. It was found (n=4) that 46±11% (SD) of the total arterial compliance is to be attributed to the ascending and
proximal descending aorta.
This work was supported in part by Grant RG 86/0066 from the scientific affairs division of Nato. 相似文献
10.
Olga Amann Merel J M Visschers Gerry M Dorrestein Ineke Westerhof J T Lumeij 《Avian pathology》2006,35(1):58-62
Exocrine pancreatic insufficiency (EPI) is a well-studied syndrome in domestic animals. EPI occurs when severe progressive loss of tubulo-acinar tissue from atrophy or inflammatory destruction results in insufficient secretion of digestive enzymes and clinical signs of malabsorption. However, the literature on EPI in birds is limited. The syndrome has been previously described in several cases where the diagnosis was based on clinical signs due to malabsorption-like light-coloured voluminous faeces, voracious appetite, coprophagia and weight loss, and on the response to treatment with pancreatic enzyme formulas. To enable a more scientific approach to the diagnosis of pancreatic functional disorders in pigeons, reference values of plasma amylase (382 to 556 IU/l), lipase (0 to 5 IU/l), and faecal activities of amylase (13 to 16 IU/l) and trypsin (11 to 14 IU/l) were determined in 24 adult pigeons. A case of EPI in a racing pigeon (Columba livia domestica) is reported, based on the clinical signs and the measurement of faecal amylase and trypsin activity. 相似文献