Objective To investigate the clinical and pathological characteristics and prognosis of IgA nephropathy (IgAN) patients with uniformly thin glomerular basement membrane (TGBM)， as well as the relationship between IgAN with TGBM and thin glomerular basement membrane disease (TGBMD). Methods According to systematic measurement of GBM thickness by electron microscope (EM)， the IgAN patients were divided into two subgroups: IgAN with normal-GBM， and IgAN with TGBM. Based on the clinicopathological data， the clinical and pathological analysis and the linkage analysis with COL4A3/COL4A4 gene in three IgAN with TGBM pedigrees were performed. Microsatellites PAX3 and HaeⅢ-RFLP， closely linked to the COL4A3 and COL4A4 loci at 2q35-37， were used as genetic linkage markers. Family genetic linkage analysis was performed with the Population and Pedigree Analysis Programs. Results The normal thickness of GBM was (352.43±32.11) nm， and the TGBM(205.56±23.48) nm in IgAN patients. (1) 31.4% (21/66) patients were accompanied with TGBM in the familial IgAN (FIgAN)， while only 11% (24/219) in the sporadic IgAN. (2) The clinical manifestations of 30 IgAN patients with TGBM were generalized as following: predominant in the affected female， persistent haematuria， the high incidence of familial history with renal disease， the less quantity of urinary protein and benign clinical courses. (3) Linkage analysis in three IgAN with TGBM pedigrees indicated that two of them were linked with PAX3， HaeⅢ-RFLP makers of COL4A3/COL4A4 gene respectively， and the LOD score was 1.53 (θ=0.00). Conclusions The clinical features of IgAN patients with TGBM are different from those with normal GBM. Some families of IgAN with TGBM may converge with the families of TGBMD， so the electron microscopy examination is necessary for familiar IgAN.

Objective To evaluate the application of 99mTc-DTPA renography in the determination of GFR. Methods One hundred and ninety-seven patients with primary or secondary chronic kidney disease participated in this study. A 3 mci(111 MBq)/0.5 ml dose of 99mTc-DTPA was injected as a bolus in an antecubital vein. Renal scintigraphic images were collected immediately and the images were processed according to standard procedure (Gates method)to obtain GFR. Four ml of blood was withdrawn 2 h and 4 h postinjection respectively and radioactivity of 1 ml plasma was measured. GFR was calculated by the formula of two-sample method. The results by two methods were all standardized with the body surface. The patients were divided into three subgroups according to the GFR obtained by two-sample method and the correlation between two methods was analysed respectively. Results The GFR[ml&#8226;min-1&#8226;(1.73 m2)-1]obtained from Gates method and two-sample method was displayed as follows:group A: 27.08±12.14 vs. 17.68±5.66； group B: 63.18±23.59 vs. 51.95±16.81； group C: 107.28±27.36 vs. 117.96±24.17. The correlation coefficients of three subgroups were as follows: rA=0.286(P = 0.012)； rB=0.804(P < 0.01)； rC=0.473(P < 0.01). Conclusion Gates method is acceptable for evaluating the GFR in patients with normal to moderately diminished renal function， but it is less precise in those with severe renal insufficiency.

Objective To investigate the correlation between urinary protein components and renal pathology in primary glomerulonephritis (PGN) patients of different pathological types. Methods One hundred and seventeen PGN patients without any special treatment were enrolled in this study. All these patients underwent renal biopsy. Scr and 24-hour urinary protein quantity were measured before the biopsy. Urinary samples were collected to analyze the protein components. Results The highest urinary concentrations of albumin (Alb) and β2-microglobumin (β2-MG) were found in patients with minimal change disease (MCD) and sclerosing glomerulonephritis (SGN)respectively. Urinary IgG/Tpro，transferrin (TRF) and β2-MG were significantly correlated with the renal tubulointerstitial scores (RTIS) and IgG/Tpro was also significantly correlated with the glomerular sclerosis. Urinary TRF and β2-MG were important influencing factors of RTIS in IgA nephropathy (IgAN) and MCD respectively， meanwhile， urinary TRF， IgG， λ light chain and β2-MG were important influencing factors of RTIS in membranous nephropathy (MN) as well. Conclusions There are differences of urinary components among PGN patients with different pathological types. Urinary IgG， TRF and β2-MG are significantly correlated with renal tubulointerstitial damage.

Objective To explore the molecular mechanisms underlying therapeutic responses of the anti-proteinuria drugs from the view of podocyte molecule. Methods Adriamycin (ADR) nephropathy was induced by a single tail intravenous injection of adriamycin. Lisinopril， prednisone and all-trans retinoic acid (ATRA) were administered once a day to the adriamycin-induced nephrotic rats at the first day after adriamycin injection respectively. Renal tissue samples were collected at day 3， 7， 14， and 28 after adriamycin injection respectively. The distribution， mRNA expression and protein expression of nephrin， podocin， CD2AP and α-actinin-4 were examined by indirect immunofluorescence， real-time PCR and Western blotting， respectively. The interactions among nephrin and podocin， nephrin and CD2AP， as well as the nephrin phosphorylation were detected by immunoprecipitation， respectively. Results Compared to the control rats， 24 h urinary protein of the ADR rats increased significantly at day 14 (P < 0.01). Compared with the ADR rats， lisinopril， prednisone and ATRA significantly reduced the excretion of urinary protein and alleviated the fusion of foot process at day 14 and 28 (P < 0.05). By analyzing the expression changes of podocyte molecules at different time points， three intervention drugs all resulted in the expression change of nephrin， podocin， CD2AP and increased the tyrosine phosphorylation of nephrin. Lisinopril and prednisone firstly diminished the abnormal change of podocin， whereas ATRA firstly diminished the abnormal change of CD2AP. Simultaneously， the staining of nephrin， podocin， CD2AP and α- actinin-4 also revealed the normal pattern after the intervention of lisinopril， prednisone and ATRA. The interactions between nephrin and podocin， nephrin and CD2AP were always maintained either in ADR rats or in three drug-intervention rats. Conclusion The anti-proteinuria effect of lisinopril， prednisone and ATRA is achieved by stabilizing the expression and distribution of important podocyte molecules， nephrin， podocin and CD2AP.

Objective To search the susceptibility candidate megsin gene and P-selectin gene of IgA nephropathy by detecting single nucleotide polymorphism (SNP) and to provide important data for subsequent case-control association study. Methods A comprehensive survey was performed on 12 sporadic IgAN patients and 12 normal controls ，who were from Shanghai， Jiangsu and Zhejiang Han populations， by direct sequencing. 13 591 bp of genomic sequence， including entire coding region， promoter region， part of regulatory region， and exon-intron connection region， was assayed to detect SNPs. Results After the results of sequencing were analyzed， 11 SNPs in SERPINB7 gene and 16 in SELP gene were identified in a total of 27 SNPs， with an average frequency of 1SNP per 503 bp. Ten SNPs， 37% of 27 SNPs， had not been reported in GenBank. Conclusion Our findings not only provide important data for subsequent case-control association study，but also are beneficial to genetic variation bank of Chinese population.

Objective To examine the expression of angiopoietin-like protein(ANGPTL)3 in kidneys from children with primary nephrotic syndrome. Methods Immunohistochemistry for ANGPTL3 was performed in kidney biopsies from patients with nephrotic syndrome or hematuria， including MCD (n=31)， MN(n=6)， FSGS (n=6)， TBMN (n=10)， IgA nephropathy(IgAN) with mesangial proliferation (n=16). Normal renal tissue of 2 cases with nephrectomy for tumor were used as control. According to the episode， four groups were divided (“< 1 month” “1~ < 6 months” “6~12 months” and “>12 months”). The expression was quantitatively examined with IMS color image analysis system， using positive index (PI) as sediment degree of ANGPTL3 in glomeruli or tubules. Immunofluorescence for ANGPTL3 co-labeling with WT1 and perlecan was applied to show the distribution of ANGPTL3. Results (1) The PI levels of ANGPTL3 in glomeruli of MCD(7.49±1.96) and MN (6.27±0.98) were significantly higher than those of TBMN(0.02±0.001)， FSGS(3.14±0.49) or normal control(0.02±0.001) respectively (all P < 0.05). The PI level of ANGPTL3 in glomeruli of IgAN patients accompanied with proteinuria was significantly higher than that of IgAN patients accompanied with hematuria (1.90±0.81 vs. 0.03±0.01， P < 0.05). (2) Co-labeling with WT1， a marker of podocyte， showed that ANGPTL3 was expressed in the cytosol of WT1 positive cells under immunofluorescent microscope. Co-labeling with perlecan， a molecule secreted by podocyte and expressed in GBM， showed a strong positive selectively distribution at the periphery of glomerular capillary loops. (3) The PI level of ANGPTL3 in glomeruli was positively correlated with the ratio of urinary protein and creatinine ， positively with FPW(r = 0.86， 0.84； P < 0.05)， and negatively with the PI level of perlecan in glomeruli (r = -0.83； P < 0.05).(4) No difference was found among the four groups for the expression of ANGPTL3 nor perlecan. Conclusions In human kidney，ANGPTL3 is selectively expressed in podocytes. The expression of ANGPTL3 in glomeruli increases with the urinary protein leakage and the fusion of foot processes.

Objective To study the inhibitive effect and mechanism of PPARγ1 on the extracellular matrix (ECM) accumulation of mesangial cells induced by AngⅡ.Methods The plasmid of PPARγ1/WT (wild type) was transfected into mesangial cells. After 48 hours of AngⅡ stimulation， the gene expression of TGF-β1， PAI-1， c-fos and c-jun was examined by RT-PCR. Protein levels of p-ERK， I-κB and nucleus/cytosol ratio of NF-κB were estimated by Westen-blot. The concentrations of FN and TGF-β1 were estimated by ELISA. The activity of PPARγ1 was examined by specific PPRE binding activity. Plasmid expressing non-functional dominant negative type of mPPARγ1， pIRES2-EGFP-mPPARγ1/DN (DN)， and blank plasmid， pIRES2-EGFP(Blank) were used as controls. Effects of 6 μmol/L PPARγ agonist pioglitazone (Pio) were also studied. Results The expression of TGF-β1 and PAI-1 mRNA in mesangial cells induced by AngⅡ was inhibited by PPARγ1 (P < 0.05). The over-expression of PPARγ1 down-regulated the expression of c-fos and c-jun significantly (P < 0.05). The expression of AT1 was enhanced by AngⅡ， whereas it was significantly inhibited by the PPARγ1(P<0.05). FN and TGF-β1 production were decreased by PPARγ1/WT transfection. PPARγ1 significantly up-regulated the low-expressed I-κB of cytoplasm and down-regulated the transfer of NF-κB from cytoplasm to nuclear by AngⅡ (P <0.05). PPARγ1/DN did not show the above effects. Pioglitazone had the same effects as PPARγ1 on these parameters in mesangial cells when treated with AngⅡ medium(P < 0.05). The activity of PPARγ1 in the PPARγ1/WT transfected group was significantly higher than that in other groups(P < 0.05). Conclusions PPARγ1 inhibits ECM accumulation induced by AngⅡ through suppressing the expression of AT1， which involves its inhibitory effects on activation of ERK/AP-1 and NF-κB pathways.

Objective To investigate the effect of surfactant protein A(SP-A) on the production of MIP-2 and binding activity of NF-κB in rat tubular epithelial cells， and evaluate its possible role in renal inflammation. Methods Confluent cultures of NRK-52E cells (a renal tubular epithelial cell line of rat origin) were pretreated with various concentrations of SP-A(0 to 80 μg/ml) and stimulated by lipopolysaccharide (LPS) (10 μg/ml) with 2% serum. MIP-2 expression was measured by enzyme-linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR). The effect of SP-A on NF-κB binding activity was assessed by electrophoretic mobility shift assay (EMSA). Results MIP-2 mRNA and protein was expressed and up-regulated in NRK-52E cells stimulated by LPS. The expression of MIP-2 was down-regulated by SP-A. NF-κB binding activity was inhibited by SP-A in a concentration-dependent manner. Conclusion SP-A binding activity and down-regulates the expression of MIP-2 in renal tubular epithelial cells，which may play an important role in the modulation of renal tissue inflammation.