Plasmonic Photoelectrochemical Coupling Reactions of para-Aminobenzoic Acid on Nanostructured Gold Electrodes.

Surface plasmon resonance (SPR) bridges photonics and photoelectrochemistry by providing an effective interaction between absorption and confinement of light to surface electrons of plasmonic metal nanostructures (PMNs). SPR enhances the Raman intensity enormously in surface-enhanced Raman spectroscopy (SERS) and leads to the plasmon-mediated chemical reaction on the surface of nanostructured metal electrodes. To observe variations in chemical reactivity and selectivity, we studied the SPR photoelectrochemical reactions of para-aminobenzoic acid (PABA) on nanostructured gold electrodes. The head-to-tail coupling product "4-[(4-imino-2,5-cyclohexadien-1-ylidene)amino]benzoic acid (ICBA)" and the head-to-head coupling product p,p'-azodibenzoate (ADBA) were obtained from PABA adsorbed on PMN-modified gold electrodes. In particular, under acidic and neutral conditions, ICBA was obtained as the main product, and ADBA was obtained as the minor product. At the same time, under basic conditions, ADBA was obtained as the major product, and ICBA was obtained as the minor product. We have also provided sufficient evidence for the oxidation of the tail-to-tail coupling reaction product that occurred in a nonaqueous medium rather than in an aqueous medium. The above finding was validated by the cyclic voltammetry, SERS, and theoretical calculation results of possible reaction intermediates, namely, 4-aminophenlylenediamine, 4-hydroxyphenlylenediamine, and benzidine. The theoretical adsorption model and experimental results indicated that PABA has been adsorbed as para-aminobenzoate on the gold cluster in a bidentate configuration. This work offers a new view toward the modulation of selective surface catalytic coupling reactions on PMN, which benefits the hot carrier transfer efficiency at photoelectrochemical interfaces.

The quantifying relationship between the remission duration and the cardiovascular and kidney outcomes in the patients with primary nephrotic syndrome.

BACKGROUND: Patients with persistent nephrotic-range proteinuria have a high risk of kidney dysfunction and cardiovascular events. Recently, the maintenance of proteinuria remission has been demonstrated to reduce the risk of kidney endpoint. However, the effect of remission duration on cardiovascular outcomes remains unclear. METHODS: This study enrolled 982 patients with primary nephrotic syndrome who had achieved clinical remission. Remission duration was defined as the maintenance time (months) of the first remission. Arteriosclerotic cardiovascular disease (ASCVD) and kidney dysfunction (ESKD or eGFR reduction >50%) were the endpoints. Survival curves, Cox regression models, restricted cubic spline analysis were used and the cutoff time points were determined. RESULTS: During the 38.3 months of follow-up, 161 (16.4%) patients developed ASCVD (51.3 per 1000 patient-years) and 52 (5.3%) patients developed kidney dysfunction (15.3 per 1000 patient-years). Multivariate analysis showed that remission duration was an independently protective factor to ASCVD, in which each one-year extension associated with a 15% reduction of the risk (HR, 0.854; 95% CI, 0.776 ∼ 0.940, p = .001). The initial time point was seven months for remission to present the protective effect to ASCVD and the maximum time point was 36 months. Remission duration was also an independently protective factor to kidney dysfunction. This effect was shown from the beginning of remission and reached the maximum at 26 months. CONCLUSIONS: The maintenance of proteinuria remission was crucial for the improvement of cardiovascular and kidney outcomes in nephrotic syndrome patients.

Membranous Nephropathy in Pregnancy.

BACKGROUND: Primary membranous nephropathy (pMN) is less common in women of child-bearing age. The kidney risk factors to adverse maternal-fetal outcomes and the effects of pregnancy on pMN process need to be investigated. METHODS: We retrospectively screened all the patients with biopsy-proven pMN from 2008 to 2018. Any cases of pregnancy that occurred at the time of pMN diagnosis or during follow-up were included in the study. Clinical and pathological data were collected from all patients at the time of kidney biopsy and their gestational results were recorded. RESULTS: Of the 27 pregnancies with gestational time of 35.9 ± 4.5 weeks, 10 adverse maternal-fetal events occurred, including fetal loss (11%), preterm delivery (26%), and severe preeclampsia (15%). The kidney parameters were relatively stable with all preserved kidney function. Time-averaged urinary protein (p < 0.001) and serum albumin (p < 0.001), maximum urinary protein (p = 0.001) and minimum serum albumin (p = 0.01) before week 20, anti-phospholipase A2 receptor (PLA2R) positivity (p = 0.03), and no remission during pregnancy (p = 0.004) were risk factors to adverse maternal-fetal outcomes. Time-averaged urinary protein and serum albumin correlated with the birth weight percentile of neonates. CONCLUSIONS: Pregnancy in pMN patients showed risks to adverse maternal-fetal events. Heavy proteinuria, especially before week 20 of gestation, severe hypoalbuminemia, positive anti-PLA2R, and no remission were risk factors to worse outcomes.

Complement activation products in the circulation and urine of primary membranous nephropathy.

BACKGROUND: Complement activation plays a substantial role in the pathogenesis of primary membranous nephropathy (pMN). C5b-9, C3c, MBL, and factor B have been documented in the subepithelial immune deposits. However, the changing of complement activation products in circulation and urine is not clear. METHODS: We measured the circulating and urinary levels of C1q, MBL, C4d, Bb, properdin, C3a, C5a, and sC5b-9, in 134 patients with biopsy-proven pMN, by enzyme-linked immunosorbent assay. All the plasma values were corrected by eGFR and all the urinary values were corrected by urinary creatinine and urinary protein excretion. Anti-PLA2R antibodies were measured in all patients. RESULTS: The plasma complement activation products were elevated both in the patients with and without anti-PLA2R antibodies. C3a levels were remarkably increased in the circulation and urine, much higher than the elevated levels of C5a. C5b-9 was in normal range in plasma, but significantly higher in urine. The urinary C5a had a positive correlation with anti-PLA2R antibody levels and urinary protein. The plasma level of C4d was elevated, but C1q and MBL were comparable to healthy controls. Positive correlations were observed between plasma C4d/MBL and urinary protein, only in the patients with positive anti-PLA2R antibodies but not in those without. The plasma level of Bb was elevated and had positive correlation with urinary protein only in the patients without anti-PLA2R antibodies. CONCLUSION: Complement activation products were remarkable increased in pMN and may serve as sensitive biomarkers of disease activity. The complement may be activated through lectin pathway with the existence of anti-PLA2R antibodies, while through alternative pathway in the absence of antibody.

HLA class II alleles differing by a single amino acid associate with clinical phenotype and outcome in patients with primary membranous nephropathy.

Genome-wide associations and HLA genotyping have revealed associations between HLA alleles and susceptibility to primary membranous nephropathy. However, associations with clinical phenotypes and kidney outcome are poorly defined. We previously identified DRB1*1501 and DRB1*0301 as independent risk alleles for primary membranous nephropathy. Here, we investigated HLA associations with demographic characteristics, anti-phospholipase A2 receptor (PLA2R) antibody, treatment response and kidney outcome after a median follow-up of 52 months in 258 patients. DRB1*0301, but not DRB1*1501, was associated with a significantly higher level of PLA2R antibody (odds ratio 1.58, 95% confidence interval 1.13-2.22). Although DRB1*1502, which differs from DRB1*1501 by a single amino acid, was not a risk allele for primary membranous nephropathy (odds ratio 1.01), it was associated with significantly lower estimated glomerular filtration rates both at baseline (1.79, 1.18-2.72) and at last follow-up (1.72, 1.17-2.53), a significantly worse renal outcome by Kaplan-Meier analysis and a significantly higher risk of end-stage renal disease by Cox regression analysis (hazard ratio 4.52, 1.22-16.74). Nevertheless, the absence of remission remained the only independent risk factor for end-stage renal disease by multivariate analysis. DRB1*1502 was also associated with a significantly higher median PLA2R antibody level [161.4 vs. 36.3 U/mL] and showed interaction with DRB1*0301 for this variable. Thus, HLA genes control PLA2R antibody production and primary membranous nephropathy severity and outcome. Additionally, DRB1*1502 behaves like a modifier gene with a strong predictor value when associated with HLA risk alleles. Other modifier genes need further investigations in larger cohorts.

Antibodies against M-Type Phospholipase A2 Receptor May Predict Treatment Response and Outcome in Membranous Nephropathy.

BACKGROUND: Anti-phospholipase A2 receptor (PLA2R) antibodies are specific to the diagnosis of primary membranous nephropathy (pMN). The prevalence of positive antibodies varies among different cohorts. Still there is discrepancy in regard to the association between antibody levels and clinical courses, and the prognostic value of antibodies to treatment responses and kidney outcomes. METHODS: Three hundred fifty-nine consecutive kidney biopsy-proven pMN patients were enrolled. Anti-PLA2R antibodies were detected by immunofluorescence assay (IFA) and enzyme-linked immunosorbent assay (ELISA). RESULTS: The positive rate of anti-PLA2R antibodies in pMN was 65.2% (234/359) by IFA and 56.3% (202/359) by ELISA. The antibody level presented positive correlation with urinary protein excretion (r = 0.164, p = 0.002). Detectable antibodies and a higher level of proteinuria were independent risk factors to no-remission after treatments (OR 3.15, p = 0.004; OR 1.11, p = 0.006) and were independent risk factors to no-spontaneous remission (OR 2.20, p = 0.011; OR 1.36, p < 0.001). A higher level of antibodies (hazard ratio 1.002, p = 0.019) was the independent risk factor to kidney dysfunction during follow-up. The antibodies turned negative in 42 out of 52 (80.8%) patients who achieved clinical remission, while they remained positive in all patients of the no-response category (p < 0.001). CONCLUSION: We documented correlations between anti-PLA2R antibody levels and clinical severity in this large Chinese pMN cohort. Antibody positivity and higher antibody level might predict treatment responses and kidney outcomes of pMN.

Rituximab for non-responsive idiopathic membranous nephropathy in a Chinese cohort.

Background: Rituximab had been shown to be effective in inducing remission of nephrotic syndrome in patients with idiopathic membranous nephropathy (iMN). This study applied rituximab therapy for 36 non-responsive iMN patients to investigate its effects and safety. Methods: Thirty-six iMN patients who were non-responsive to prior immunosuppression were enrolled. Rituximab was used for B-cell depletion in patients, with a goal of <5 B cells/mm3 in the circulation. After completing the study, patients were monitored for a median of 12.0 months [interquartile range (IQR) 9.0-19.3]. Results: Fifteen of the 36 (41.7%) patients achieved partial (n = 13) or complete (n = 2) response to the rituximab treatment. The median time for achieving partial response was 4.0 months (IQR 3.0-6.0). The responders had relatively lower levels (118 ± 112 U/mL versus 345 ± 357 U/mL, P = 0.03) of anti-phospholipase 2 receptor (PLA2R) antibodies before the rituximab treatment, and all of them achieved antibody depletion or reduction. B-cell depletion was achieved in all patients. Renal function remained stable in the responders [estimated glomerular filtration rate (eGFR) 53.3 ± 40.5 versus 55.6 ± 33.2 mL/min/1.73 m2, P = 0.67] but deteriorated in the non-responders (eGFR 57.5 ± 29.3 versus 45.3 ± 32.8 mL/min/1.73 m2, P = 0.02) with two patients reaching end-stage kidney disease. Two of the 15 patients relapsed during the follow-up period with anti-PLA2R antibody reoccurrence and B-cell reconstitution. The second course of rituximab combined with tacrolimus induced a faster partial response again in one patient. Conclusion: Rituximab therapy could induce remission of proteinuria and stabilization of renal function in non-responsive iMN patients, even those with damaged renal function. Anti-PLA2R antibodies may be used as a marker for individualized rituximab dosage and treatment monitoring.

Clinical implications of pathological features of primary membranous nephropathy.

BACKGROUND: The clinical outcome varies considerably in primary membranous nephropathy (pMN). Risk factors for kidney prognosis include ageing, male gender, persistent heavy proteinuria, decreased eGFR at presentation, persistent elevation of anti-PLA2R antibodies, no remission, and so on. It was controversial whether the histopathological features of pMN could predict treatment response and kidney outcome. METHODS: A retrospective study was conducted in 371 patients with biopsy-proven pMN. Pathological parameters included immunofluorescence staining, membranous Churg's stages, sclerosis, crescent, focal segmental sclerosis lesion, chronic and acute tubulointerstitial injury. The fluorescence intensity was determined: 0, negative; 1, weak; 2, moderate; 3, strong; 4, glaring. Chronic tubulointerstitial injury was graded by the involved area: 0, 0-5%; 1, 6-25%; 2, 26-50%; 3, > 50%. RESULTS: We found that patients with higher intensity of C3 staining, advanced membranous stage, and more severe chronic tubulointerstitial injury presented with higher positivity rate of anti-PLA2R antibodies, higher levels of urinary protein excretion and serum creatinine, and lower level of serum albumin. Univariate Cox regression analysis showed that severe (grade = 3) chronic tubulointerstitial injury was a risk factor to the kidney outcome of ESKD (HR = 61.02, 95%CI, 7.75-480.57, P < 0.001) and over 50% reduction of eGFR (HR = 4.43, 95%CI, 1.26-15.6, P = 0.021). Multivariate analysis demonstrated it as an independent risk factor to ESKD (HR = 25.77, 95% CI, 1.27-523.91, P = 0.035). None of the pathological parameters exerted any influence on treatment response (P > 0.05). CONCLUSIONS: We found the prognostic role of chronic tubulointerstitial injury to the kidney outcome of pMN. This study highlighted the value of kidney biopsy under the widespread usage of anti-PLA2R antibodies for diagnosis and prognosis.

MHC Class II Risk Alleles and Amino Acid Residues in Idiopathic Membranous Nephropathy.

Epitopes of phospholipase A2 receptor (PLA2R), the target antigen in idiopathic membranous nephropathy (iMN), must be presented by the HLA-encoded MHC class II molecules to stimulate autoantibody production. A genome-wide association study identified risk alleles at HLA and PLA2R loci, with the top variant rs2187668 within HLA-DQA1 showing a risk effect greater than that of the top variant rs4664308 within PLA2R1. How the HLA risk alleles affect epitope presentation by MHC class II molecules in iMN is unknown. Here, we genotyped 261 patients with iMN and 599 healthy controls at the HLA-DRB1, HLA-DQA1, HLA-DQB1, and HLA-DPB1 loci with four-digit resolution and extracted the encoded amino acid sequences from the IMGT/HLA database. We predicted T cell epitopes of PLA2R and constructed MHC-DR molecule-PLA2R peptide-T cell receptor structures using Modeler. We identified DRB1*1501 (odds ratio, 4.65; 95% confidence interval [95% CI], 3.39 to 6.41; P<0.001) and DRB1*0301 (odds ratio, 3.96; 95% CI, 2.61 to 6.05; P<0.001) as independent risk alleles for iMN and associated with circulating anti-PLA2R antibodies. Strong gene-gene interaction was noted between rs4664308(AA) and HLA-DRB1*1501/DRB1*0301. Amino acid positions 13 (P<0.001) and 71 (P<0.001) in the MHC-DRß1 chain independently associated with iMN. Structural models showed that arginine13 and alanine71, encoded by DRB1*1501, and lysine71, encoded by DRB1*0301, facilitate interactions with T cell epitopes of PLA2R. In conclusion, we identified two risk alleles of HLA class II genes and three amino acid residues on positions 13 and 71 of the MHC-DRß1 chain that may confer susceptibility to iMN by presenting T cell epitopes on PLA2R.

Urinary soluble urokinase receptor levels are elevated and pathogenic in patients with primary focal segmental glomerulosclerosis.

BACKGROUND: Focal segmental glomerulosclerosis (FSGS) is a major cause of end-stage renal disease. Recent studies have proposed that plasma soluble urokinase receptor (suPAR) might be a causative circulating factor but this proposal has caused controversy. This study aimed to measure urinary suPAR levels in patients with primary FSGS and its significance in the pathogenesis of FSGS. METHODS: Sixty-two patients with primary FSGS, diagnosed between January 2006 and January 2012, with complete clinical and pathologic data were enrolled, together with disease and normal controls. Urinary suPAR levels were measured using commercial ELISA kits and were corrected by urinary creatinine (Cr). The associations between urinary suPAR levels and clinical data at presentation and during follow up were analyzed. Conditionally immortalized human podocytes were used to study the effect of urinary suPAR on activating ß3 integrin detected by AP5 staining. RESULTS: The urinary suPAR level of patients with primary FSGS (500.56, IQR 262.78 to 1,059.44 pg/µmol Cr) was significantly higher than that of patients with minimal change disease (307.86, IQR 216.54 to 480.18 pg/µmol Cr, P = 0.033), membranous nephropathy (250.23, IQR 170.37 to 357.59 pg/µmol Cr, P <0.001), secondary FSGS (220.45, IQR 149.38 to 335.54 pg/µmol Cr, P <0.001) and normal subjects (183.59, IQR 103.92 to 228.78 pg/µmol Cr, P <0.001). The urinary suPAR level of patients with cellular variant was significantly higher than that of patients with tip variant. The urinary suPAR level in the patients with primary FSGS was positively correlated with 24-hour urine protein (r = 0.287, P = 0.024). During follow up, the urinary suPAR level of patients with complete remission decreased significantly (661.19, IQR 224.32 to 1,115.29 pg/µmol Cr versus 217.68, IQR 121.77 to 415.55 pg/µmol Cr, P = 0.017). The AP5 signal was strongly induced along the cell membrane when human differentiated podocytes were incubated with the urine of patients with FSGS at presentation, and the signal could be reduced by a blocking antibody specific to uPAR. CONCLUSIONS: Urinary suPAR was specifically elevated in patients with primary FSGS and was associated with disease severity. The elevated urinary suPAR could activate ß3 integrin on human podocytes.

Ultrastructural changes of podocyte foot processes during the remission phase of minimal change disease of human kidney.

AIM: The current study was designed to observe the ultrastructural changes of podocyte foot processes during the remission phase and its relationship with the amount of the proteinuria in patients with minimal change disease (MCD). METHODS: Electron micrographs of glomerular capillaries were taken from 33 adult cases with MCD, including 12 cases with nephrotic syndrome, 15 cases in partial remission and six cases in complete remission. The foot processes were classified into three grades by the ratio of the height to basal width: 0.5-1, 1-2 and ≥2. The foot process width (FPW) and the number of foot processes in different grades per 10 µm of glomerular basement membrane (GBM) were measured. Normal renal tissues from 12 nephrectomies for renal carcinoma were selected as controls. RESULTS: There were statistical differences (P = 0.001) in the mean FPW among the nephrotic group (1566.4 ± 429.4 nm), partial remission group (1007.8 ± 234.9 nm), complete remission group (949.8 ± 168.2 nm) and normal controls (471.9 ± 51.8 nm). For the height-to-width ratio ≥2, the number of foot process per 10 µm GBM was significantly greater in the normal group than that in the complete remission group (0.84 ± 0.24 vs. 3.84 ± 1.80, P = 0.016). Taking all three groups of patients together, the mean FPW showed correlation with the level of proteinuria (r = 0.506, P = 0.003). CONCLUSION: There may be no causal relationship between proteinuria and foot process effacement. In complete remission phase, both FPW and shape of foot process had not returned to normal while proteinuria disappeared.

Plasma soluble urokinase receptor levels are increased but do not distinguish primary from secondary focal segmental glomerulosclerosis.

In this study, we measured soluble urokinase receptor levels, a possible permeability factor, in the plasma of patients with primary focal segmental glomerulosclerosis (FSGS) and determined their association with clinical and pathological data in 74 patients with primary FSGS. Healthy donors and patients with minimal change disease, membranous nephropathy, and secondary FSGS were used as controls. The plasma-soluble urokinase receptor levels, measured by commercial ELISA kits, of patients with primary FSGS (median: 2923, interquartile range 2205-4360 pg/ml) were significantly higher than those of patients with minimal change disease (median 2050 pg/ml), membranous nephropathy (median 2029 pg/ml), and normal individuals (median 1739 pg/ml). There was no significant difference in plasma-soluble urokinase receptor levels between the 74 patients with primary and 14 patients with secondary FSGS. The soluble urokinase receptor levels increased in the order of tip variant, to a not otherwise specified variant and a cellular variant. The soluble urokinase receptor levels were significantly but negatively correlated with creatinine clearance at presentation but positively correlated with crescent formation in patients with primary FSGS. During follow-up, receptor levels decreased significantly in patients with complete remission. Thus, plasma-soluble urokinase receptor levels did not differentiate primary and secondary FSGS, and although significantly elevated in FSGS, they showed considerable overlap with other glomerular diseases.

Long-term visit-to-visit variability in low-density lipoprotein cholesterol is associated with poor cardiovascular and kidney outcomes in patients with primary nephrotic syndrome.

PURPOSE: It is unclear whether long-term variability in low-density lipoprotein cholesterol (LDL-C) is associated with clinical outcomes in patients with nephrotic syndrome (NS). METHODS: A large cohort of 1100 patients with primary NS underwent treatment and regular follow-up. Long-term variability in LDL-C was assessed by calculating its weighted standard deviation (w-SD). The primary endpoints of this study were the occurrence of arteriosclerotic cardiovascular disease (ASCVD) or kidney dysfunction. Factors associated with the w-SD of LDL-C were evaluated by linear regression. Associations of the w-SD of LDL-C with clinical outcomes were evaluated by Cox proportional hazards regression. RESULTS: Over a median follow-up of 44.8 (interquartile range, 26.8, 70.1) months, 198 patients developed ASCVD (45.9 cases per 1,000 patient-years), and 84 patients developed kidney dysfunction (17.6 cases per 1,000 patient-years). The incidence rates of the primary outcomes increased across the quartiles of the w-SD of LDL-C (log-rank, P < 0.001). Multivariate Cox regression analysis showed that higher LDL-C variability was associated with an increased risk of ASCVD [hazard ratio (HR), 2.236; 95% confidence interval (CI), 1.684-2.969, P < 0.001] and an increased risk of kidney dysfunction (HR, 3.047; 95% CI 2.240-4.144, P < 0.001). The results were similar after adjusting the w-SD of LDL-C by its related parameters (baseline and mean LDL-C as well as mean total cholesterol), although the mean LDL-C was also an independent risk factor for ASCVD and kidney dysfunction. CONCLUSION: Long-term variability in LDL-C was independently associated with the risk of ASCVD and kidney dysfunction in NS patients.

Effects of hydroxychloroquine on proteinuria in membranous nephropathy.

BACKGROUND: Many patients with primary membranous nephropathy have severe proteinuria unresponsive to optimized renin-angiotensin-aldosterone system inhibitors (RAASi). We evaluated the efficacy and safety of hydroxychloroquine as an adjunctive agent in membranous nephropathy (MN) treatments. METHODS: We prospectively recruited 126 patients with biopsy-proven primary membranous nephropathy and urinary protein 1-8 g/day while receiving optimized RAASi treatment for ≥ 3 months and well-controlled blood pressure. Forty-three patients received hydroxychloroquine and RAASi (hydroxychloroquine-RAASi group), and 83 patients received RAASi alone (RAASi group). Treatment responses, including proteinuria reduction, complete and partial remission rates, and autoantibody against phospholipase A2 receptor (anti-PLA2R) levels, were compared between the two groups at 6 months and over the long term. RESULTS: At 6 months, the effective response rate (proteinuria reduction > 30%) (57.5% vs. 28.9%, P = 0.002), clinical remission rate (35.0% vs. 15.7%, P = 0.015), and percentage change in proteinuria (- 51.7% vs. - 21.9%, P < 0.001) were higher, and the rate of switching to immunosuppressants (25.0% vs. 45.8%, P = 0.027) was lower in the hydroxychloroquine-RAASi group than in the RAASi group. Hydroxychloroquine administration was an independent protective factor with an effective response (OR 0.37, P = 0.021). In the long term, the clinical remission rate was higher in the HCQ-RAASi group (62.5% vs. 38.6%, P = 0.013). Hydroxychloroquine therapy was associated with a higher rate of anti-PLA2R reduction (< 20 U/ml) (HR 0.28, P = 0.031). We observed no serious adverse events associated with hydroxychloroquine. CONCLUSIONS: Hydroxychloroquine could be an option for patients with membranous nephropathy seeking to achieve proteinuria reduction and anti-PLA2R antibody reduction in addition to optimized RAASi. Randomized controlled trials are needed to confirm these findings. TRIAL REGISTRATION: ChiCTR2100045947, 20210430, retrospectively registered.

Rituximab Therapy for Primary Membranous Nephropathy in a Chinese Cohort.

Background: Rituximab has become one of the first-line therapies for the treatment of moderate and high-risk primary membranous nephropathy (pMN). We retrospectively reviewed 95 patients with pMN who received rituximab therapy and focused on the therapeutic effects and safety of this therapy in a Chinese cohort. Methods: Ninety-five consecutive patients with pMN diagnosed by kidney biopsy received rituximab and were followed up for >6 months. Four weekly doses of rituximab (375 mg/m2) was adopted as the initial administration. Repeated single infusions were administrated to maintain B cell depletion levels of <5 cells/mL. Results: A total of 91 patients completed rituximab therapy with the total dose of 2.4 (2.0, 3.0) g; 64/78 (82.1%) patients achieved anti-PLA2R antibody depletion in 6.0 (1.0, 12.0) months; 53/91 (58.2%) patients achieved clinical remission in 12.0 (6.0, 24.0) months, including complete remission in 18.7% of patients and partial remission in 39.6% of patients. Multivariate logistic regression analysis showed that severe proteinuria (OR = 1.22, P = 0.006) and the persistent positivity of anti-PLA2R antibodies (OR = 9.00, P = 0.002) were independent risk factors for no-remission. The remission rate of rituximab as an initial therapy was higher than rituximab as an alternative therapy (73.1 vs. 52.3%, P = 0.038). Lastly, 45 adverse events occurred in 37 patients, but only one patient withdrew from treatment due to severe pulmonary infection. Conclusion: Rituximab is a safe and effective treatment option for Chinese patients with pMN, especially as an initial therapy.

[Clinical significance of detection of plasma and urine IgG4 in idiopathic membranous nephropathy].

OBJECTIVE: To investigate the possibility of IgG4/IgG as one of biomarkers to reflect disease activity and the relapse of idiopathic membranous nephropathy (IMN). METHODS: Plasma and urine samples were obtained from patients with IMN (Twenty-four patients had follow-up data), minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS) before immunosuppressive therapy. Concentrations of plasma and urine IgG4 and total IgG were detected by sandwich ELISA. The ratio of IgG4/IgG was calculated as the concentration of IgG4 divided by total IgG. RESULTS: Both plasma and urine IgG4/IgG ratios were significantly higher in IMN group compared with MCD or FSGS group (both P<0.05). In IMN, both plasma and urine IgG4/IgG ratios in patients with nephritic syndrome were significantly higher versus those with subnephrotic proteinuria (P=0.063; P<0.05). Both plasma and urine IgG4/IgG ratios were significantly decreased with remission (P<0.05) and maintained or even increased with resistance to therapy. Patients who relapsed within 2 years had higher urine IgG4/IgG-ratios than those who had no relapse (P<0.05), and patients with urine IgG4/IgG-ratios≥9% upon renal biopsy had higher relapse tendency (P=0.071). CONCLUSION: Both plasma and urine IgG4/IgG ratios might be a promising biomarker to reflect disease activity of IMN, and higher urine IgG4/IgG ratios might suggest higher relapse tendency.

[Spatial Characteristics, Risk Assessment, and Source Analysis of Elements in Surface Sediments from the Baiyangdian Lake].

In this paper, nutrient elements (N and P), heavy metals (Pb, Cu, Zn, Cd, Cr, Co, Ni, and Sn), and grain size in surface sediments of Baiyangdian Lake, northern China, are studied. We also analyze the spatial variation in elemental characteristics and undertaken a pollution risk assessment. By combining data with information on the river sediment characteristics, we use multivariate statistical methods to reveal the sources and variation of elements in sediments. The results showed that the average contents of heavy metals in surface sediments from the lake and associated rivers were higher than background values. Within the area of the lake, nutrient elements are relatively high in the northwest region but low in the southeast region, and heavy metals are relatively high in the middle of the lake but low in the southern and northern areas. The sequence of comprehensive pollution index (I) in sediments was Cd > Pb > Cr > Cu=Zn > Ni > Sn > Co, with Cd being assessed as severe pollution and other elements as moderate pollution, although severe pollution of Cr was found in the Zaolinzhuang area. The order of potential ecological risk coefficients (Eri) was determined as Cd > Pb > Cu > Cr > Ni > Zn, whereby Cd was associated with a strong potential ecological risk (except in the Caiputai area) and other elements were associated with a slight potential ecological risk. Differences in the lake sediment texture were found to be slight. Non-point source pollution after rivers flow into the lake was determined as the main reason for the spatial variation of elements in the surface sediments of Baiyangdian Lake, although point source pollution in the villages surrounding the lake should not be ignored, especially with respect to N, P, Pb, and Cr.

Complement activation profile of patients with primary focal segmental glomerulosclerosis.

BACKGROUND: Studies on adriamycin mice model suggest complement system is activated and together with IgM contributes to the glomerular injury of primary focal segmental glomerulosclerosis (FSGS). We recently reported primary FSGS patients with IgM and C3 deposition showed unfavorable therapeutic responses and worse renal outcomes. Here we examined the plasma and urinary complement profile of patients with primary FSGS, aiming to investigate the complement participation in FSGS pathogenesis. METHODS: Seventy patients with biopsy-proven primary FSGS were enrolled. The plasma and urinary levels of C3a, C5a, soluble C5b-9, C4d, C1q, MBL, and Bb were determined by commercial ELISA kits. RESULTS: The levels of C3a, C5a and C5b-9 in plasma and urine of FSGS patients were significantly higher than those in normal controls. The plasma and urinary levels of C5b-9 were positively correlated with urinary protein, renal dysfunction and interstitial fibrosis. The plasma C5a levels were positively correlated with the proportion of segmental sclerotic glomeruli. The urinary levels of Bb were elevated, positively correlated with C3a and C5b-9 levels, renal dysfunction, and interstitial fibrosis. The plasma C1q level was significantly decreased, and negatively correlated with urinary protein excretion. Urinary Bb level was a risk factor for no remission (HR = 3.348, 95% CI 1.264-8.870, P = 0.015) and ESRD (HR = 2.323, 95% CI 1.222-4.418, P = 0.010). CONCLUSION: In conclusion, our results identified the systemic activation of complement in human primary FSGS, possibly via the classical and alternative pathway. The activation of complement system was partly associated with the clinical manifestations, kidney pathological damage, and renal outcomes.

[Clinicopathologic characteristics and outcomes of IgA nephropathy in elder patients].

OBJECTIVE: To investigate the clinical, pathological characteristics and outcomes of IgA nephropathy in the elderly. METHODS: Seventy patients over age 60 with IgA nephropathy were studied and compared with 82 patients under 60 years in the clinical and pathological features as well as the outcomes. RESULTS: Compared with non-elderly group, elder group patients had higher blood pressure [systolic pressure (142.0+/-20.4) mmHg vs (124.2+/-16.9) mmHg (1mmHg=0.133 kPa), diastolic pressure (83.1+/-11.8) mmHg vs (78.9+/-12.3) mmHg], serum creatinine [(172.7+/-125.8) micromol/L vs (94.4+/-42.5) micromol/L], serum cholesterol[(5.7+/-1.6) mmol/L vs (5.1+/-1.6) mmol/L], 24 hj urinary protein excretion rate [(3.4+/-2.9) g/d vs (1.8+/-2.0) g/d], and the incidence of CKD stages 3-5(64.0% vs 14.6%)(P<0.05). No significant differences were seen in the disease courses, rate of gross hematuria, serum triglyceride and serum IgA level between two groups(P>0.05).Renal pathological investigation showed the chronic lesions were dominated in elder group. There was significant difference in portion of glomerular sclerosis [(19.7+/-20.1)% vs (13.4+/-17.8)%], renal tubule atrophy (>1 score,34.2% vs 25.6%), interstitial fibrosis (>1,score 34.2% vs 18.2%), and arteriolosclerosis (>2 score,20.0% vs 8.5%) between two groups (P<0.05). However, there were no significant difference in proportion of mesangial proliferation, crescent and interstitial inflammatory cell infiltration (P>0.05). After a mean post-biopsy follow-up of (34.6+/-33.3) months, the 3-year and the 5-year renal survival rates for elder group were 74.6% and 62.2%, respectively, which were lower than those of non-elder group (100% and 92.9%, P=0.002). CONCLUSION: Elder patients with IgA nephropathy were more likely to suffer from hypertension, hyperlipidemia, renal insufficiency and chronic pathologic lesions, which might be the risk factors for the patient's unfavorable prognosis.

Clinical and prognostic significance of glomerular C1q deposits in primary MN.

BACKGROUND: Although complement activation is believed to be important in mediating PMN, the pathways involved and clinical consequences remain controversial. Many cases of idiopathic or primary membranous nephropathy (PMN) present with subepithelial C1q deposits along with IgG and C3 on glomerular capillary walls but without deposits of IgA or IgM ("full house") by immunofluorescence or any causes of secondary MN. We sought to define the clinical and pathological significance of these C1q deposits in PMN by comparing a variety of clinical parameters, outcomes and other serum and urine factors in patients with and without significant glomerular C1q deposits. METHODS: Two-hundred eighty-eight patients with biopsy-proven PMN were enrolled. We compared the clinical and pathological features, treatment responses and kidney outcomes, between patients with and without C1q deposition. Circulating anti-PLA2R antibodies and complement components in plasma and urine were detected by ELISA. RESULTS: Glomerular C1q deposition was detected on capillary walls by immunofluorescence in 66/288 (22.9%) patients. C1q-positive patients presented with lower concentrations of serum IgG (5.3 ±â€¯3.1 vs. 6.6 ±â€¯3.5 g/l, p = 0.008), a higher frequency of IgA (37.9% vs. 15.8%, p < 0.001), IgM (48.5% vs. 31.5%, p = 0.011) and C3c (100% vs. 88.3%, p = 0.004) deposits in glomeruli and more stage III of MN (24.2% vs. 11.7%, p < 0.001) by pathologic criteria. Other features, including gender, age, anti-PLA2R antibody positivity and concentrations, proteinuria, albumin and serum creatinine, were not different between the patients with and without C1q deposition (p > 0.05). The IgG subclasses of anti-PLA2R antibodies in circulation or in glomeruli showed no difference (p > 0.05). C1q deposition, and C1q concentrations in circulation and urine had no apparent effect on the treatment responses or kidney outcomes (p > 0.05). CONCLUSION: The classical pathway of complement is activated in some patients with PMN, but may not play an essential role in mediating the kidney injury seen in this disease.