Objective To illustrate if the racial coefficient (RC) be biased by different reference GFR (rGFR) distribution among studies. Methods 1405 white and 321 African-American participants in MDRD study and 684 chronic kidney disease(CKD) patients in Chinese eGFR Investigation Study were included. Firstly, the unweighted datasets of white and Chinese were stacked together. rGFR, age and plasma creatinine (Pcr) were log transformed. Linear regression model was constructed using log transformed rGFR as dependent, gender, race and log transformed Pcr and age as independent. Unweighted RC (uRC) for Chinese was calculated. Then, the Chinese CKD distribution of rGFR was weighted to be the same as that in White American, and weighted RC (wRC) for Chinese was calculated. The cases of White- and African-American were stacked together. The cases of African-American were weighted to make the rGFR distribution the same as that in White- American and Chinese population respectively, and RCs for African-American were calculated. Results The uRC for Chinese was 1.197 (1.180-1.211) and the wRC was 1.130 (1.117-1.143). The two RCs did not overlap with each other. The RCs for African-American were 1.205 (1.191-1.219) and 1.233 (1.219-1.247) respectively. Conclusions The RCs were influenced by the difference of rGFR distribution. To find out the real RC, an international collaborative study is needed, with the same rGFR measure method, strict control of Pcr measurement, and the same rGFR distribution.

Objective To study the pre-transplant serum level of anti-endothelial cell antibody (AECA) in kidney allograft recipients and its impact on the episode of acute rejection (AR) within 6 months after transplantation. Methods A total of 495 kidney allograft recipients with pre-transplant serum between December 1998 and August 2003 in our center and 40 healthy controls（negative controls）were enrolled in the study. Clinical data including AR within 6 months after transplantation were analyzed retrospectively. The serum AECA level was measured by cyto-ELISA using EA.hy926 cells as substrate, which was shown as the ratio of P (patient)/N (negative control)=(Apatient-Ablank control)/(Anegative control-Ablank control). AECA was considered positive when P/N value was greater than the average Anegative control value plus two times the standard deviation. Results Positive rate of AECA was 18.8% (93/495). AECA level in hemodialysis patients who had been on hemodialysis more than 12 months was 1.43±0.37, greater than those less than 12 months (1.27±0.32, P=0.013) and those of non-dialyzed patients (1.31±0.32, P=0.029). Correlation coefficient between AECA level and hemodialysis duration was 0.218 (P=0.018). AR incidence in AECA positive recipients was 38.7%, greater than that in AECA negative recipients (23.4%, P=0.002). Incidence of acute T cell-mediated rejection and acute antibody-mediated rejection increased significantly (P=0.035, P=0.002 respectively). Multifactor logistic regression analysis indicated that AECA positive, PRA greater than 10% and high CDC level were risk factors of AR with odds ratio of 2.056, 1.751 and 1.764 respectively (P=0.004, 0.029, 0.050). Conclusions The AECA positive in pre-transplant serum indicates the elevated risk of acute allograft rejection. The AECA level increases with prolonged hemodialysis duration.

Objective To introduce a case of varicella-zoster virus (VZV) -related glomerulonephritis and encephalitis. Methods The clinical data and renal pathology were analyzed. Associated literatures were reviewed. Results A 15 years old male patient presented nephritic syndrome, nephrotic syndrome and renal dysfunction with reduced serum complement C3 level from the 5th day after he suffered from varicella. The pathological diagnosis of his kidney tissue was endocapillary proliferative glomerulonephritis with podocyte proliferation and severe renal tubular injury by light microscopy. Immunofluorescent and electron microscopic examinations showed “full-house” staining and granular electron-dense deposits in multiple sites, respectively. Furthermore, virus-like particles or/and inclusions could also be seen by electron microscopy and Mann staining light microscopy. Positive varicella-zoster virus (VZV) specific IgM antibody was detected by serum virological test. VZV antigen and RNA transcript were found in glomerular and tubular cells by immunohistochemical staining and in situ hybridization of renal tissues, respectively. The patient had epileptic episodes for many times in his disease course and his brain MRI and electroencephalogram findings accorded with viral encephalitis with secondary epilepsy. So, the diagnosis of VZV-related glomerulonephritis and encephalitis was established. Conclusion This is the first report of VZV-related glomerulonephritis and encephalitis confirmed by serum virology and tissue virology.

Objective To investigate the role of fibroblast growth factor-23 (FGF23) in secondary hyperparathyroidism (SHPT). Methods (1) Serum FGF23 and intact parathyroid hormone (iPTH) from 38 maintenance hemodialysis (MHD) patients were measured by ELISA and chemiluminescence enzyme immunoassay respectively. (2) Parathyroid cells from six SHPT patients underwent parathyroidectomy with forearm autotransplantation were cultured for 24 h, then were induced by 0.1 mg/L FGF23. The supernatant was collected at 0, 6, 12, 24 and 48 h respectively. The concentration of iPTH was measured by chemiluminescence enzyme immunoassay. (3) Protein expression of Klotho, FGFR1, FGFR3, GATA-3 and PCNA in parathyroid tissue from 33 SHPT cases and 3 healthy people were detected by immunohistochemistry SP and PV methods respectively. Positive cell rate and absorbance were calculated. Results (1) Serum FGF23 [(3901.85±2618.11) ng/L] was positively correlated with serum iPTH [(460.00±489.77) ng/L] in MHD patients. (2) 0.1 mg/L FGF23 suppressed iPTH secretion of parathyroid cells only at 24 h time point in vitro (P＜0.05). (3) Expression of GATA-3, FGFR3, Klotho and PCNA was significantly increased and FGFR1 was significantly decreased in parathyroid tissue of SHPT patients as compared to healthy people. (4) Positive cell rate of GATA-3 was positively correlated with iPTH (r2=0.1901, P=0.0425) and PCNA (r2=0.2584, P=0.0025). Klotho was positively correlated with FGFR1 and FGFR3 (r2=0.2046, P=0.0082；r2=0.2833, P=0.0014). PCNA was negatively correlated with FGFR1 (r2=0.1292, P=0.0399) and positively correlated with FGFR3 (r2=0.1226, P=0.0457). FGFR1 was negatively correlated with serum phosphate (r2=0.2329, P=0.0044) and positively correlated with serum calcium (r2=0.1422, P=0.0305). Conclusions FGF23 level is positively correlated with iPTH level in MHD patients. FGF23 can inhibit iPTH secretion of parathyroid cells in a weak and short way, which may be associated with the proliferation of GATA-3 positive cells and parathyroid cells, the up-regulation of FGFR3 and the down-regulation of FGFR1 expression.

Objective To investigate the association of complement C1q polymorphism with the susceptibility to lupus nephritis (LN) in the people of Wuhan district, Hubei province, China. Methods The polymorphic frequency at C1q region of accommodation Aexon2, Bexon1, Bexon2, Cexon2 in 30 LN patients, 20 non-LN nephropathy controls and 10 healthy controls were examined by polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) and then the sequence of mutational site was detected directly. Association of C1q polymorphism with LN was analyzed by chi-square criterion. Results Already reported mutable points oversea, such as C1qAexon2：C→T, C1qBexon1：G→A, C1qBexon2：G→A, C1q Cexon2：C deletion, in C1q region of accommodation were not detected in 30 LN patients, 20 non-LN nephropathy controls and 10 healthy controls. Conclusion Polymorphism in the regulatory region of C1q region of accommodation is not associated with the susceptibility to LN in the people of Wuhan district, Hubei province, China, which may be influenced by a small number of subjects.

Objective To explore the association between circulating endothelial cells (CECs) and atherosclerosis in maintenance hemodialysis (MHD) patients. Methods A cross-sectional study was performed to investigate the association between CECs and carotid atherosclerotic change in 65 MHD patients，25 non-hemodialysis patients with chronic kidney disease (CKD) of stage 4 or 5 (CKD-non-HD) and 24 age- and sex-matched healthy controls. CECs in peripheral blood were determined by multiparametric flow cytometry (FCM). CECs were labeled with CD3-PerCP and CD146-PE before FCM and identified as CD3dim/CD146bright. Atherosclerosis in both groups was assessed by the measurement of common carotid artery intima-media thickness (CCA-IMT) and plaque of the common carotid arteries with ultrasound scanner. Results CECs were significantly higher in pre-dialysis patients [(151.52±98.24) cell/ml] and CKD-non-HD patients [(183.00±81.38) cell/ml] compared with control group[(106.50±24.14) cell/ml] (P<0.05 and P<0.01, respectively). But the number of CECs was not significantly different between MHD and CKD-non-HD patients. CCA-IMT was also significantly higher in MHD patients [(0.94±0.36) mm] and CKD-non-HD patients [(1.02±0.37) mm] compared with control group [(0.75±0.15) mm] (P<0.05 and P<0.01, respectively). The number of pre-dialysis CECs was positively correlated with CCA-IMT in MHD patients (r=0.328, P<0.01). Multivariate analysis showed that CEC level was a strong independent risk factor of CCA-IMT. Conclusion In MHD patients, CEC level is associated with carotid atherosclerosis and may be used as a marker to evaluate the endothelial damage.

Objective To investigate the impact of initial dialysis dose on residual renal function of peritoneal dialysis patients. Methods Clinical data of 178 consecutive patients on initial peritoneal dialysis received follow-up for 3 months in our department were analyzed retrospectively. According to urinary volume after peritoneal dialysis, patients were divided into three groups: lower urine group (LU, n=97), decreased urine group (DU, n=19), and normal urine group (NU, n=62). Their dialysate volume, dialysate glucose content, ultrafiltration, weekly renal urea clearance normalized to total body water (Kt/V), body weight, edema degree and daily urinary volume were recorded and association among these parameters were examined. Results There were no significant differences in age, gender, serum albumin and total Kt/V among three groups. One month after dialysis, body weight and edema degree in DU group were significantly higher than those in LU and NU groups (all P<0.05); the dialysate volume, dialysate glucose content, ultrafiltration and renal Kt/V in DU group were significantly higher than those in LU group (all P<0.05), but were not significantly different from NU group. Three months after dialysis, in DU group, dialysate volume, ultrafiltration and urinary volume decreased significantly (P<0.05) as compared with LU and NU groups, but body weight and edema degree were still higher, and Kt/V decreased significantly as well. Conclusions The residual renal function (urinary volume and Kt/V value) of initial patients will be deteriorated by over ultrafiltration in early stage of peritoneal dialysis. Excess ultrafiltration should be avoided for the initial peritoneal dialysis patients.

Objective To study the pathogenesis of anemia in chronic aristolochic acid nephropathy (CAAN) rats. Methods The hemoglobin (Hb) values of sixty-two male SD rats were assayed to determine its normal range. Among them, 24 rats with normal Hb value were randomly divided into 2 groups: model group (MG) in which rats received the extract of Aristolochia manshuriensis Kom (AmK) by gavage, and control group（CG）received tap water only by gavage. Body weight (BW), Hb, 24 h urinary protein excretion (UP) and creatinine clearance (Ccr) of 6 rats in each group were measured before administration and at the end of the 8th week, respectively, then these rats were sacrificed. The relative area of renal interstitial fibrosis was measured by microscopy. The mRNA expression of erythropoietin (EPO) in kidney tissue was determined by real-time RT-PCR; protein expression of typeⅠcollagen (ColⅠ), aminopeptidase P (APP), hypoxia inducible factor 1α and 2α (HIF-1α and HIF-2α) in kidney tissue was examined by immunohistochemistry staining. Results Hb values of normal rats presented normal distribution. The normal Hb was(155.9±16.5) g/L. Rat anemia was diagnosed when Hb was below 123.6 g/L. There was no difference in all the examination results between CG and MG before administration (P>0.05). Compared with CG, the Hb and Ccr in MG were significantly decreased [(121.66±15.68) g/L vs (169.00±12.89) g/L, (0.63±0.13) ml/min vs (1.27±0.18) ml/min, P<0.01], and the UP in MG was significantly increased at the end of the 8th week [ (27.04±9.40) mg/d vs (6.11±0.84) mg/d, P<0.01]; the relative areas of fibrosis and ColⅠ in renal interstitium of MG were significantly enlarged [(12.89±2.33)% vs (0.55±0.10)%, (13.92±2.92)% vs (1.32±0.84)%, P< 0.01]; the protein expression of APP and the mRNA expression of EPO in the kidney tissue of MG were significantly down-regulated [(0.55±0.23)% vs (3.77±1.06)%, 0.005±0.001 vs 0.032±0.013, P<0.01]; the protein expression of HIF-1α and HIF-2α in the kidney tissue of MG was significantly up-regulated (2.55±0.16 vs 1.12±0.46, 2.33±0.33 vs 1.15±0.27, P<0.01), at the end of the 8th week. Conclusions The pathogenesis of anemia in CAAN may be due to the decreased production of EPO caused by the destruction of peritubular capillary. The compensatory up-regulation of HIF-1α and HIF-2α expression can not prevent the anemia development.

Objective To detect the functional repair of metanephric mesenchymal cells (MMCs) transplantation in adriamycin (ADR)-induced glomerulopathy rats. Methods A total of 90 Sprague-Dawley female rats were randomly divided into three groups: ADR group (n=40, rats were injected via the tail vein with 0.25 mg ADR/100 g body weight on days 1 and 21), ADR-MMCs group (n=40, rats were injected via the tail vein with 5×106-7×106 MMCs 8 weeks after the second ADR administration), control (n=10). All the rats were scarified 8 weeks after MMCs injection. Pathology and collagen Ⅳ expression in renal tissue were examined. Moreover, matrix metalloproteinases 2 (MMP-2) and matrix metalloproteinases 9 (MMP-9) expression in the renal tissue were also detected with immunohistochemistry, and quantity analysis of protein and gene was further demonstrated with Western blot and RT-PCR analysis, respectively. Results There were no significant differences in tubulointerstitial injury score and glomerulosclerosis degree between ADR group and ADR-MMCs group (P>0.05). Compared with ADR group, collagen Ⅳ and MMP-2 expression decreased, MMP-9 expression increased in renal tissue of ADR-MMCs group, and the difference was significant (P<0.05). Conclusion MMCs transplantation may have potentially therapeutic effect on renal tissue fibrosis of adriamycin-induced glomerulopathy in rats, and the signaling pathways of MMPs appear to be involved in these processes.