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Markus Exner

Publications and source records attributed to Markus Exner.

At least 73 records · Page 4Linked to original sources
PubMed2003

Restenosis after femoropopliteal PTA and elective stent implantation: predictive value of monocyte counts.

PURPOSE: To investigate the association of baseline peripheral blood monocyte counts and restenosis after femoropopliteal percutaneous transluminal angioplasty (PTA) and PTA plus elective stent implantation. METHODS: Three hundred thirty consecutive patients (170 men; median age 71 years, interquartile range 61-78) with peripheral artery disease underwent femoropopliteal PTA (n=258) or PTA plus elective stent implantation (n=72). Multivariate Cox regression analysis was used to determine the predictive value of baseline peripheral blood monocyte counts on the rate of restenosis (> or =50% luminal reduction) in follow-up. RESULTS: Cumulative patency at 6 and 12 months was 55% and 39% after PTA and 70% and 41% after elective stenting, respectively (p=0.19). Pretreatment monocyte counts (in tertiles) were associated with restenosis after PTA (p=0.002) and stent implantation (p=0.02). Compared to patients with monocyte counts <0.3x10(9)/L (lower tertile, n=128), patients with monocytes from 0.3 to 0.4x10(9)/L (middle tertile, n=91) had a 1.8-fold increased adjusted risk for restenosis (95% CI 1.1 to 2.8, p=0.01). Patients with monocytes >0.4x10(9)/L (upper tertile, n=87) had a 2.3-fold increased adjusted risk (95% CI 1.4 to 3.5, p<0.0001). CONCLUSIONS: Baseline monocyte counts were associated with restenosis after femoropopliteal PTA and elective stent implantation, suggesting that circulating monocytes play a pivotal role in the development of recurrent lumen narrowing.

Aged↗
PubMed2002

A case of severe C4d-positive kidney allograft dysfunction in the absence of histomorphologic features of rejection.

Acute antibody-mediated (humoral) renal allograft rejection has emerged as a clinicopathological entity that carries a poor prognosis. Its diagnosis is based on typical pathohistologic features, serologic detection of donor-specific alloantibodies and the immunohistochemical finding of endothelial deposits of the complement split product C4d. We herein report a case of severe antibody-mediated graft injury after spousal-donor kidney transplantation. Despite an increased risk for humoral presensitization in the female recipient (three previous pregnancies), donor-specific alloantibodies were not detectable before transplantation. After initial graft function, severe graft dysfunction occurred one week after transplantation. A renal biopsy revealed no histomorphologic features of rejection. However, immunohistochemical detection of diffuse C4d deposits along peritubular capillaries suggested acute humoral rejection. The diagnosis of antibody-mediated rejection was confirmed by the detection of de-novo production of anti-donor alloantibodies. Graft dysfunction was resistant to high dose steroids or antilymphocyte antibody therapy. However, a recovery of graft function could be achieved by antibody elimination using immunoadsorption therapy. This case reinforces the high diagnostic value of C4d staining. In severe graft dysfunction humoral immune mechanisms should be considered, even when histopathologic features of humoral rejection are completely absent.

Adult↗
PubMed2002

The K121Q polymorphism in the plasma cell membrane glycoprotein 1 gene predisposes to early myocardial infarction.

Elevated plasma cell membrane glycoprotein 1 (PC-1) expression and the frequent PC-1 K121Q polymorphism have recently been associated with insulin resistance. Since insulin resistance represents an important risk factor for atherosclerotic vascular disease and myocardial infarction, we investigated the involvement of the PC-1 K121Q polymorphism in the development of myocardial infarction. We analyzed two independent series of cardiovascular patients at a defined end-point of atherosclerotic vascular disease (those having suffered myocardial infarction) for the PC-1 K121Q mutation by a newly developed mutagenic separated PCR assay. In both patient groups the presence of the Q allele was significantly associated with younger age at the time of first myocardial infarction, suggesting a more rapid progression of endothelial dysfunction. In a multivariate analysis carriers of the 121Q allele from Vienna and from Central Germany exhibited a 2.6- and a 4.2-increased odds, respectively, for suffering myocardial infarction within the first tertile of age (<51 and <48 years, respectively). Our data indicate that the PC-1 121Q allele might predispose independently of other well established risk factors for early myocardial infarction. Testing for the PC-1 K121Q polymorphism might be valuable in patients with a family history of atherosclerotic vascular disease and myocardial infarction.

Adult↗
PubMed2002

Expression of functional CCR and CXCR chemokine receptors in podocytes.

Chemokines and their receptors play an important role in the pathogenesis of acute and chronic glomerular inflammation. However, their expression pattern and function in glomerular podocytes, the primary target cells in a variety of glomerulopathies, have not been investigated as of yet. Using RT-PCR, we now demonstrate the expression of CCR4, CCR8, CCR9, CCR10, CXCR1, CXCR3, CXCR4, and CXCR5 in cultured human podocytes. Stimulation of these receptors induced a concentration-dependent biphasic increase of the free cytosolic calcium concentration in podocytes in culture. In addition, we demonstrate that podocytes release IL-8 in the presence of FCS and that IL-8 down-regulates cell surface CXCR1. Chemokine stimulation of the detected CCRs and CXCRs increased activity of NADPH-oxidase, the primary source of superoxide anions in podocytes. Immunohistochemistry studies revealed only diffuse and weak CXCR expression in healthy human glomerula. In contrast, in membranous nephropathy, a characteristic podocyte disorder, the expression of CXCR1, CXCR3, and CXCR5 is up-regulated in podocytes. In conclusion, podocytes in culture and podocytes in human kidney sections express a set of chemokine receptors. The release of oxygen radicals that accompanies the activation of CCRs and CXCRs may contribute to podocyte injury and the development of proteinuria during membranous nephropathy.

Calcium↗
PubMed2002

Heme oxygenase-1 gene promoter polymorphism is associated with abdominal aortic aneurysm.

OBJECTIVE: Vascular inflammation is a hallmark in the development of abdominal aortic aneurysms (AAA). Heme oxygenase-1 (HO-1) is a novel vascular anti-inflammatory factor. A (GT)(n) dinucleotide repeat in the HO-1 gene promoter shows a length polymorphism that modulates the level of gene transcription. Short (< 25 GT) repeats are associated with an increased HO-1 upregulation in response to inflammatory stimuli than are longer repeats. We hypothesised that patients with AAA had less frequently short repeats in the HO-1 gene promoter compared to patients with coronary (CAD) or peripheral artery disease (PAD), or healthy controls. METHODS: 70 consecutive patients with atherosclerotic AAA, each 70 age- and sex-matched patients with CAD and PAD as well as 61 unmatched healthy atherosclerosis-free controls for a total of 271 individuals were studied. The frequency of carriers of short repeats in the HO-1 gene promoter was determined and compared between the groups. RESULTS: In the AAA group, 29 patients (41%) were carriers of short (GT)(n) repeats compared to 47 patients (67%) in the CAD group, 44 patients (63%) in the PAD group and 35 healthy controls (59%). Patients with AAA were less frequently carriers of short repeats compared to age- and sex-matched patients with CAD (OR = 0.38, p = 0.006) and PAD (OR = 0.35, p = 0.01). Healthy controls exhibited short alleles more frequently than patients with AAA (p = 0.04), but comparable to CAD (p = 0.3) and PAD patients (p = 0.7). CONCLUSION: Patients with AAA were less frequently carriers of short (< 25 GT) repeats in the HO-1 gene promoter than patients with atherosclerosis or healthy subjects. This suggests that short alleles, and thus, facilitated upregulation of HO-1, may be a protective anti-inflammatory factor against the development of AAA.

Alleles↗
PubMed2002

Leptin induces endothelin-1 in endothelial cells in vitro.

Leptin, a protein encoded by the obese gene, is produced by adipocytes and released into the bloodstream. In obese humans, serum leptin levels are increased and correlate with the individual's body mass index and blood pressure. Elevated serum concentrations of endothelin-1 (ET-1), a potent vasoconstrictor and mitogen, were also observed in obese subjects. The pathomechanisms underlying this ET-1 increase in obesity are poorly understood. In the present study, we investigated the influence of the ob gene product leptin on the expression of ET-1 in human umbilical vein endothelial cells (HUVECs). Binding studies using (125)I-radiolabeled leptin revealed high- and low-affinity leptin binding sites on HUVECs (Kd1=13.1+/-3.1 nmol/L and Kd2=1390+/-198 nmol/L, respectively), mediating a time- and dose-dependent increase of ET-1 mRNA expression and protein secretion after incubation of HUVECs with leptin. This leptin-induced ET-1 expression was inhibited by preincubation of HUVECs with 0.75 micromol/L antisense phosphorothioate oligonucleotides directed against the leptin receptor Ob-Rb. Furthermore, after incubation with leptin, increased nuclear staining of c-fos and c-jun, the major components of the transcription factor AP-1, and increased AP-1 DNA binding were observed. Transient transfection studies with ET-1 promoter constructs showed that leptin-induced promoter activity was abolished in the absence of AP-1 binding sites or by cotransfection with a plasmid overexpressing a mutated jun, which is able to bind c-fos but not DNA. Thus, leptin upregulates ET-1 production in HUVECs via a mechanism potentially involving jun binding members of the bZIP family.

Cells, Cultured↗
PubMed2002

Mean platelet volume is an independent risk factor for myocardial infarction but not for coronary artery disease.

After rupture of an arteriosclerotic plaque in a coronary artery, platelets play a crucial role in the subsequent thrombus formation, leading to myocardial infarction. An increased mean platelet volume (MPV), as an indicator of larger, more reactive platelets, may represent a risk factor for myocardial infarction. However, this hypothesis is still controversial and most studies addressing the role of MPV were performed comparing patients suffering from myocardial infarction with healthy controls. We intended to identify patients at high risk of suffering myocardial infarction in a group of patients with known coronary artery disease. One hundred and eighty-five consecutive patients with stable coronary artery disease were compared with 188 individuals who had suffered myocardial infarction. Patients within the highest quintile of MPV (> or = 11.6 fl) had a significantly higher risk of experiencing a myocardial infarction compared with patients within the lowest quintile (OR = 2.6, 95% CI 1.3-5.1) in a multivariate analysis that included sex, age, body mass index, hyperlipidaemia, hypertension, smoking and diabetes mellitus. Our results indicate that patients with pre-existing coronary artery disease and an increased MPV (> or = 11.6 fl) are at higher risk of myocardial infarction. These patients can be easily identified during routine haematological analysis and could possibly benefit from preventive treatment.

Aged↗
PubMed2002

Lipoprotein (a) in patients with aortic aneurysmal disease.

OBJECTIVE: Lipoprotein (a) is an independent risk factor for atherosclerosis. Atherosclerotic degeneration is usually found in abdominal aortic aneurysms (AAAs), whereas thoracic aortic aneurysms (TAAs) caused by aortic dissection are not suggested to be linked pathogenetically to atherosclerosis. Lipoprotein (a) was analyzed in patients with AAA and TAA and in healthy individuals in relation to the extent of atherosclerosis. METHODS: Included in the case control study were patients with AAA (n = 75) and TAA with dissection (n = 39) and healthy control subjects (n = 43), for a total of 157 participants. Serum lipoprotein (a) was measured with nephelometry. Lipoprotein (a) levels were compared between age-matched and gender-matched paired samples of the three groups, and an association of lipoprotein (a), aortic aneurysm, and the extent of atherosclerosis was determined in multivariate analysis. RESULTS: Median lipoprotein (a) levels of patients with AAA and TAA and of control subjects were 18.9 mg/dL (interquartile range [IQR], <9.6 to 40.5), less than 9.6 mg/dL (IQR, <9.6 to 16.7), and less than 9.6 mg/dL (IQR, <9.6 to 16.3), respectively. Lipoprotein (a) was positively associated with the extent of atherosclerosis in patients and control subjects (P <.0001). Lipoprotein (a) levels of patients with AAA were significantly higher compared with patients with TAA (P <.0001) and control subjects (P <.0001). Multivariate analysis confirmed an independent association between lipoprotein (a) and AAA (P =.009). No significant differences of lipoprotein (a) were found between patients with TAA and control subjects (P =.3). CONCLUSION: The lipoprotein (a) serum level, an indicator of atherosclerosis, is significantly elevated in patients with abdominal aneurysms independently of cardiovascular risk factors and the extent of atherosclerosis. Patients with TAAs caused by dissection have lipoprotein (a) levels comparable with healthy individuals.

Aged↗
PubMed2002

Peri-operative immunoadsorption in sensitized renal transplant recipients.

BACKGROUND: Re-transplanted kidney allograft recipients with high levels of panel reactive antibodies (PRA) are at increased risk of early immunologic graft loss. In these patients, prophylactic peri-operative antibody depletion by immunoadsorption (IA) could prevent humoral graft injury and thus, in combination with anti-cellular rejection therapy, improve graft survival. METHODS: Twenty re-transplanted and broadly immunized cadaver kidney recipients (median PRA reactivity 87%, range 55-100%) were treated with IA (protein A) immediately before transplantation and during the early post-transplantation period (median number of IA sessions 11, range 1-24). Patients received additional prophylactic anti-lymphocyte antibody therapy. Nineteen patients had a negative pre-transplant cross-match. In one patient, a positive cross-match was rendered negative by the pre-transplant IA session. RESULTS: One-year graft survival was 80% and patient survival 95%. Median (range) serum creatinine in functioning grafts was 1.6 (0.8-2.7) mg/dl at discharge and 1.5 (1.0-5.8) mg/dl at 1 year. Two grafts were lost due to acute vascular rejection, whereby one rejection occurred after withdrawal of immunosuppression due to septicaemia. One patient had acute cellular rejection, which was reversed by a second course of anti-lymphocyte antibody therapy. Thrombotic microangiopathy and surgical complications were the causes for one graft loss each. Retrospective immunohistochemistry revealed peritubular C4d staining, a presumed marker for humoral alloreactivity, in 12 out of 15 biopsies. CONCLUSIONS: These results suggest that prophylactic peri-operative IA and anti-lymphocyte antibody therapy might be an effective therapeutic strategy for the prevention of early graft failure in sensitized re-transplant recipients.

Adult↗
PubMed2002

Acute humoral renal allograft rejection.

In kidney transplantation, it is well established that donor-specific antibodies can cause substantial graft injury. Hyperacute rejection, now virtually eliminated by routine pretransplant cytotoxic crossmatch testing, represents the prototype of humoral rejection. However, there is now increasing evidence that alloantibody-mediated immune reactions may also cause acute rejection. Acute humoral rejection, which is frequently associated with severe graft dysfunction and immunologic graft loss, represents a particular diagnostic and therapeutic challenge. Reliable detection of antibody-mediated graft injury is required to govern the application of antihumoral therapeutic strategies. This review focuses on new approaches in the diagnosis and treatment of acute humoral rejection. Special attention is given to a novel diagnostic marker, the complement split product C4d.

Antibody Formation↗
PubMed2002

Capillary deposition of complement split product C4d in renal allografts is associated with basement membrane injury in peritubular and glomerular capillaries: a contribution of humoral immunity to chronic allograft rejection.

Endothelial deposition of the complement split product C4d is an established marker of antibody-mediated acute renal allograft rejection. A contribution of alloantibody-dependent immune reactions to chronic rejection is under discussion. In this study, the association of immunohistochemically detected endothelial C4d deposition in peritubular capillaries (PTC) with morphologic features of chronic renal allograft injury was investigated in a large study cohort. C4d deposits in PTC were detected in 73 (34%) of 213 late allograft biopsies performed in 213 patients more than 12 mo after transplantation (median, 4.9 yr) because of chronic allograft dysfunction. Endothelial C4d deposition was found to be associated with chronic transplant glomerulopathy (CG) (P < 0.0001), with basement membrane multilayering in PTC (P = 0.01), and with an accumulation of mononuclear inflammatory cells in PTC (P < 0,001). Furthermore, C4d deposits in PTC (in biopsies with normal glomerular morphology) were associated with development of CG in follow-up biopsies. Other morphologic features of chronic allograft nephropathy (with exception of tubular atrophy) were not associated with C4d deposits in PTC. Analyses of previous and follow-up biopsies revealed that C4d deposits may occur de novo and may also disappear at any time after transplantation. In conclusion, the data suggest that complement activation in renal microvasculature, indicating humoral alloreactivity, contributes to chronic rejection characterized by chronic transplant glomerulopathy and basement membrane multilayering in PTC.

Adult↗
PubMed2002

Inflammatory response to stent implantation: differences in femoropopliteal, iliac, and carotid arteries.

PURPOSE: To investigate the postintervention course of serum acute-phase reactants after stent implantation in the femoropopliteal, iliac, and carotid arteries. MATERIALS AND METHODS: This prospective cohort study included 274 consecutive patients who underwent stent implantation in the femoropopliteal (n = 95), iliac (n = 70), and carotid (n = 109) arteries. C-reactive protein (CRP), serum amyloid A (SAA), and fibrinogen levels were measured at baseline and at 48 hours after intervention. Polynomial logistic regression analysis was applied to assess the independent association of the course of acute-phase reactants and the site of stent implantation. RESULTS: Stent implantation in the femoropopliteal artery was associated with a higher postintervention increase in CRP (P =.01), SAA (P =.04), and fibrinogen (P =.01) values compared with values with iliac artery stent implantation, with adjustment for age, sex, fluoroscopy duration, contrast agent dose, complication occurrence, stenosis grade, total vessel occlusion, and stent cumulative length. No significant difference in the postintervention course of CRP (P =.9) and SAA (P =.1) levels was determined for stents implanted in the carotid artery compared with those implanted in the iliac artery; however, a higher increase in fibrinogen levels (P =.04) was noted. CONCLUSION: Stent implantation in the muscular femoropopliteal artery was associated with a more extensive vascular inflammatory response than was stent implantation in the elastic iliac and carotid arteries, independent of lesion morphology and interventional factors.

Aged↗
PubMed2002

Vascular inflammation and percutaneous transluminal angioplasty of the femoropopliteal artery: association with restenosis.

PURPOSE: To determine the association of pre- and postprocedural serum levels of C-reactive protein (CRP), serum amyloid A (SAA), and fibrinogen at 6-month evaluation of restenosis after percutaneous transluminal angioplasty (PTA) of the femoropopliteal artery. MATERIALS AND METHODS: In a prospective cohort study, 172 consecutive patients with peripheral artery disease of Fontaine stage IIa, IIb, or III who underwent successful PTA of the superficial femoral and popliteal arteries were included. Patency at 6 months was evaluated by using oscillography, ankle-brachial index, and color-coded duplex ultrasonography. The association of restenosis and CRP, SAA, and fibrinogen levels at baseline, 24 hours, and 48 hours after intervention was assessed by means of multivariate analysis with adjustment for known risk factors for restenosis. RESULTS: Restenosis was found in 56 patients (33%) within 6 months. CRP values at baseline (adjusted odds ratio, 2.2; 95% CI: 1.1, 4.2) and 48 hours after intervention (adjusted odds ratio, 2.3; 95% CI: 1.6, 3.1) were independently associated with 6-month restenosis. SAA and fibrinogen values at any time interval were not significantly associated with patency in the multivariate models. CONCLUSION: The extent of vascular inflammation as measured by means of acute-phase reactants before and after PTA of the femoropopliteal artery is associated with 6-month restenosis. Baseline and 48-hour CRP levels were independent predictors of postangioplasty outcome.

Acute-Phase Proteins↗
PubMed2002

Balloon angioplasty and stent implantation induce a vascular inflammatory reaction.

PURPOSE: To investigate whether peripheral balloon angioplasty with and without stent implantation independently causes an inflammatory vascular response measured by serum acute-phase reactants. METHODS: This was a prospective cohort study enrolled 388 consecutive patients (218 men; median age 70 years, interquartile range 59-76) with peripheral artery disease undergoing balloon angioplasty (n = 187), stent implantation (n = 140), and diagnostic angiography (control group, n = 61). C-reactive protein (CRP) measured by standard and high-sensitivity assays, serum amyloid A (SAA), fibrinogen, and white blood cell (WBC) count were obtained at baseline and at 8, 24, and 48 hours postintervention. Polynomial logistic regression analysis was used to assess the independent association of acute-phase reactants and the interventional group. RESULTS: CRP levels measured by both standard and the high-sensitivity assays significantly increased after balloon angioplasty (standard CRP, p = 0.02; high-sensitivity CRP, p = 0.02) and stent implantation (standard CRP, p = 0.004; high-sensitivity CRP, p = 0.008) compared to the control group adjusting for age, sex, duration of fluoroscopy, volume of contrast, and periprocedural complications. SAA values differed only between the stent group and controls (p = 0.05). Fibrinogen and WBCs were not different among the 3 interventional groups. CONCLUSIONS: Balloon injury and stent implantation induce a vascular inflammatory response at the dilated vessel segment measurable by serum acute-phase parameters. The standard CRP assay is adequate to quantify acute-phase response in these patients.

Aged↗
PubMed2002

Heme oxygenase-1 genotype is a vascular anti-inflammatory factor following balloon angioplasty.

PURPOSE: To investigate the association of the heme oxygenase-1 (HO-1) genotype, which has potent anti-inflammatory capability, and the inflammatory response induced by balloon angioplasty. METHODS: Three hundred seventeen patients (188 men; median age 70 years, range 57-77) undergoing femoropopliteal balloon angioplasty (n=150) or stenting (n=61) were evaluated for upregulation of the HO-1 genotype; 106 patients undergoing lower limb angiography served as controls. The acute phase reactants C-reactive protein (CRP), serum amyloid A (SAA), and fibrinogen were measured 24 and 48 hours postintervention and compared to baseline values. An association of the relative increase (Delta, %) of these inflammatory markers with short (<25) (GT)(n) dinucleotide repeats in the HO-1 gene promoter was assessed. RESULTS: The HO-1 genotype was significantly associated with Delta CRP(24) (p<0.0001), Delta CRP(48) (p<0.0001), Delta SAA(24) (p=0.02), and Delta SAA(48) (p=0.006) after balloon angioplasty; Delta fibrinogen showed no association. Patients with a higher Delta CRP(48) after balloon angioplasty exhibited significantly reduced odds for the presence of short (<25) (GT)(n) repeats. The adjusted odds reduction in the multivariate model was 80% (p=0.002) in the third quartile of Delta CRP(48) values and 90% (p=0.001) in the fourth quartile. No association of HO-1 genotype and inflammatory response was found 24 and 48 hours after stenting (p=0.3, p=0.5) or angiography (p=0.2, p=0.6). CONCLUSIONS: The HO-1 promoter genotype is independently associated with the inflammatory response seen after balloon angioplasty. Short alleles (<25 GT repeats) seem to be an intrinsic vascular anti-inflammatory factor.

Aged↗
PubMed2002

Capillary C4d deposition in kidney allografts: a specific marker of alloantibody-dependent graft injury.

Capillary deposition of the complement split product C4d has been discussed as a marker for antibody-mediated kidney allograft rejection. The relationship between C4d staining and posttransplant alloantibody detection remains to be thoroughly investigated, however. In this study, C4d staining in peritubular capillaries (PTC) and the incidence of alloantibody formation, as detected with sensitive techniques, were evaluated among a cohort of transplant recipients who had undergone biopsies and had not been selected for a specific histologic diagnosis. One hundred thirteen biopsies, obtained from 58 cadaveric kidney transplant recipients, were tested. Serum samples obtained at the time of biopsy were evaluated by flow cytometric crossmatch (FCXM) testing and FlowPRA (One Lambda, Inc., Canoga Park, CA) analysis of anti-HLA panel reactivity. Most biopsies with C4d deposits in PTC (C4d(PTC)(+), n = 21 of 24) were associated with positive posttransplant FCXM results (T and/or B cell FCXM) and/or > or =5% FlowPRA (anti-HLA class I and/or II) reactivity. Approximately 50% of the C4d(PTC)(-) biopsies were observed to be associated with donor-specific alloantibodies. Accordingly, high specificity (93%) but low sensitivity (31%) were calculated for capillary C4d staining (with FCXM testing as the standard method). For clinical evaluation, three patient groups were defined, i.e., a group of recipients with positive C4d staining in at least one allograft biopsy (C4d(PTC)(+), n = 16) and two C4d(PTC)(-) groups, which were discriminated on the basis of posttransplant FCXM results as C4d(PTC)(-)/FCXM(+) (n = 22) and C4d(PTC)(-)/FCXM(-) (n = 20) groups. Univariate analyses revealed significant differences between these groups with respect to serum creatinine levels at 12 mo [median, 2.83 mg/dl (interquartile range, 1.93 to 4.2 mg/dl) versus 1.78 mg/dl (1.47 to 2.24 mg/dl) versus 1.59 mg/dl (1.2 to 1.71 mg/dl), P < 0.001]. Of the five immunologic graft losses, four occurred in the C4d(PTC)(+) group and one occurred in the C4d(PTC)(-)/FCXM(+) group. In a multivariate analysis, C4d positivity was observed to have an independent predictive value for inferior 12-mo graft function (P = 0.02), whereas the observed moderate difference between C4d(PTC)(-)/FCXM(+) and C4d(PTC)(-)/FCXM(-) recipients did not achieve significance. In conclusion, these data demonstrate that positive C4d staining, which is an independent predictor of kidney graft dysfunction, represents a reliable specific marker for antibody-dependent graft injury.

Adult↗
PubMed2002

Interleukin-1 receptor antagonist genotype is associated with coronary atherosclerosis in patients with type 2 diabetes.

Recently, inflammation has received considerable attention in the pathogenesis of both type 2 diabetes and atherosclerosis. The interleukin-1 receptor antagonist (IL-1ra) is a major modulator of the interleukin-1 pro-inflammatory pathway. We studied the relationship between a variable number tandem repeat (VNTR) polymorphism in intron 2 of the IL-1ra gene (IL1RN) and coronary artery disease (CAD) in patients with and without type 2 diabetes, following 787 consecutive patients admitted for suspected CAD. According to the current criteria of the American Diabetes Association, 250 patients had type 2 diabetes. In this group of patients, allele 2 carriers (n = 108) had an increased prevalence of CAD compared with noncarriers (85.2 vs. 73.2%), a difference that remained significant in a multivariate logistic regression model (odds ratio 2.2, 95% CI 1.1-4.3, P = 0.02). No association of CAD with allele 2 carrier status was present among nondiabetic patients (n = 537). Enzyme-linked immunosorbent assays showed decreased baseline plasma levels of IL-1ra in patients with type 2 diabetes, which may in part explain the role of the IL1RN VNTR in these patients.

Aged↗