Objective To analyze the distribution of glomerular immunofluorescence IgG4 subtypes in primary membranous nephropathy, and to explore the relationship between IgG4 deposit intensity and renal pathology, clinical manifestations and prognosis. Methods All the patients of biopsy-proven primary membranous nephropathy with IgG staining and at least one IgG subtype staining 1+ or higher on capillary loops from September 2015 to April 2017 were retrospectively enrolled. The distribution of IgG4 deposits were analyzed, and the relationship between IgG4 positive intensity and clinical manifestations, pathological indexes and clinical remission was investigated. Results A total of 250 cases were enrolled, including 157 males (62.8%) and 93 females (37.2%), and age was (54.4 ± 14.6) years. There were 40 patients in IgG4-negative group, and 210 patients in IgG4-positive group. The IgG4-positive group was divided into subgroups as 114 cases of the mild positive subgroup (1+) and 62 cases of the moderate positive subgroup (2+), and 34 cases of the strong positive subgroup (3+, 4+). The IgG4-positive group had higher 24-hour urine protein and higher positive rate of phospholipase A2 receptor staining than those in the negative group (both P<0.05), while the strong positive subgroup had lower serum albumin and higher IgG1 staining than those in the mild positive subgroup (both P<0.05). There was no difference in the ratio of glomerular sclerosis, tubular atrophy, IgG2, IgG3 or other immunofluorescence between the groups. After a median follow-up of 180(122, 209) days, 32 individuals were lost to follow-up. Among the rest 218 patients, 45 patients (20.6%) got complete remission, 104 patients (47.7%) got partial remission, and 69 patients (31.7%) showed no response. For no response as the outcome event, multivariate Cox regression analysis showed that higher IgG4 staining intensity (HR=1.371, 95%CI 1.068-1.759, P=0.013), male (HR=1.818, 95%CI 1.028-3.214, P=0.040), higher 24-hour urine protein level (HR=1.108, 95%CI 1.003-1.225, P=0.043) were independent risk factors for disease remission. Conclusions The glomerular IgG4 positivity and intensity are related to the severity of primary membranous nephropathy. The glomerular IgG4 deposit degree may be an effective prognostic marker for the treatment response of primary membranous nephropathy.

Objective To find out the prognostic influencing factors of patients undergoing continuous renal replacement therapy (CRRT) for refractory acute left heart failure. Methods Through the medical system and hemodialysis system in Foshan First People's Hospital, all patients who received CRRT for refractory acute left ventricular heart failure from January 1, 2012 to January 1, 2019 were searched. All patients were divided into two groups by the final outcome: survival group and death group. Age, sex, initial mean arterial pressure (MAP), primary heart disease, use of vasoactive drugs, urine output before treatment, hemoglobin, serum creatinine, serum albumin, C-reactive protein(CRP), brain natriuretic peptide (BNP)，cardiac ejection fraction (EF) and CRRT treatment time were analyzed to find out the prognostic influencing factors. Results A total of 130 cases were collected, including 96 cases in the survival group and 34 cases in the death group, with a total mortality rate of 26.15%. Compared to that in the death group, there were higher proportion of males (71.88% vs 50.00%, χ²=5.366, P=0.021), significantly higher initial MAP (t=4.677, P<0.001), much more urine output before treatment (Z=3.904, P<0.001), significantly higher serum creatinine (Z=2.866, P=0.004）, significantly lower hemoglobin (Z=-2.587, P=0.011), significantly shorter time of CRRT (Z=-3.447, P=0.001) in the survival group. Multivariate logistic regression analysis showed that female (OR=2.950, 95%CI 1.102-7.898, P=0.031) and higher levels of hemoglobin (OR=1.024, 95%CI 1.004-1.045, P=0.019) were the risk factors of death in patients undergoing CRRT for refractory acute left heart failure, while higher levels of mean arterial pressure before treatment (OR=0.959, 95%CI 0.930-0.989, P=0.008) and urine volume before treatment (OR=0.998, 95%CI 0.997-0.999, P=0.004) were the protective factors for patients' prognosis. Conclusion The mortality of patients with refractory acute left heart failure undergoing CRRT therapy is still very high. Female and higher level of hemoglobin are the risk factors for death, while more urine volume before treatment and higher MAP before treatment are protective factors for survival.

Objective To clarify the relationship between the hemoglobin level and renal tubular atrophy/interstitial fibrosis (T) in the Oxford stage of renal pathology in IgA nephropathy (IgAN) patients. Methods Patients diagnosed with IgAN by renal biopsy from January 1^st 2010 to December 31^st 2015 in Shenzhen Second People's Hospital with complete laboratory and imaging data were retrospectively analyzed. Patients were divided into anemic group and non-anemic group. The relationship between hemoglobin level and renal tubular atrophy/interstitial fibrosis was determined by logistic regression analysis. The possible curve relationship between hemoglobin and renal tubular atrophy/interstitial fibrosis was analyzed by smooth curve fitting analysis. The diagnostic value of hemoglobin for renal tubular atrophy/interstitial fibrosis was analyzed by the receiver operating curve (ROC). Results A total of 630 patients with IgAN were included in this study, 130 patients in the anemia group (20.63%) and 500 patients in the non-anemia group (79.37%). There was no statistically significant difference in age between the two groups, but the difference of the gender was statistically significant (male 35.38% vs 53.80%, χ²=10.740, P<0.001). Compared with the non-anemia group, the anemia group had a higher proportion of tubular atrophy/interstitial fibrosis ( χ²=62.586, P<0.001), higher 24 h urinary protein quantification (Z=-6.082, P<0.001), and lower eGFR (t=7.126, P<0.001). Multivariate logistic regression analysis showed that increasing hemoglobin level was an independent protective factor for reducing the risk of renal tubular atrophy/interstitial fibrosis (OR=0.973, 95%CI 0.958-0.987, P<0.001). Smooth curve fitting analysis showed that there was a linear negative correlation between hemoglobin and tubular atrophy/interstitial fibrosis. The ROC curve suggested that the best threshold of hemoglobin was 120.5 g/L when renal tubular atrophy/interstitial fibrosis occurred. That was, when hemoglobin was above 120.5 g/L, the severity level of renal tubular atrophy interstitial fibrosis might be reduced. Conclusion The incidence of renal tubular atrophy/ interstitial fibrosis is higher in IgAN patients with anemia, and hemoglobin>120.5 g/L may reduce the risk of tubular atrophy/interstitial fibrosis.

Objective To identify and analyze the variants of the KCNJ1 gene in five Chinese patients with Bartter syndrome type 2 (BS2), and to describe their clinical features as well as treatment results. Methods Data and blood samples of five BS2 patients and their relatives confirmed by Qingdao Municipal Hospital from June 2012 to January 2019 were collected. Whole-exome-sequencing (WES) based on the second generation high throughput sequencing was performed to detect variants. The 2015 American College of Medical Genetics and Genomics Standards and Guidelines were applied to analyze the pathogenicity of the variants. The clinical features and laboratory results were retrospectively studied. The response to treatment and follow-up data were reviewed. Results Ten variants including six novel ones of KCNJ1 gene were identified through WES and verified by Sanger dideoxy sequencing. Missense variants accounted for the highest proportion. The common symptoms and signs of five BS2 patients from high to low incidence were polydipsia and polyuria (5/5), one of them (1/5) presented with diabetes insipidus; maternal polyhydramnios and premature delivery (4/5); growth retardation (3/5). Initially, two patients presented with hypochloremic metabolic alkalosis and hypokalemia, whereas the acid-base disturbance was absent in the others. One patient experienced hyperkalemia. In terms of calcium-phosphorus metabolism, one patient had evident parathyroid hormone (PTH) resistance (hypocalcemia, hyperphosphatemia and markedly elevated serum intact PTH levels), three presented with PTH overacting (hypercalcemia, hypophosphatemia and mild elevated serum intact PTH levels), and one showed normal blood calcium and phosphorus concentrations with high-normal serum intact PTH levels. All patients had nephrocalcinosis or hypercalciuria, and one of them complicated with nephrolithiasis. Indomethacin helped to correct the growth retardation, halt polydipsia polyuria, decrease the elevated urinary calcium excretion, and normalize electrolyte disturbance as well as PTH parameters in some patients. Conclusions This investigation identifies ten variants of KCNJ1 gene, including six ones that have not been previously reported, which will enrich the human gene mutation database (HGMD). These patients in our study have atypical BS phenotype, so that careful differentiation from other parathyroid diseases will be required for clinicians.

Objective To explore the clinical and cytogenetic characteristics and risk factors of multiple myeloma (MM) patients with renal impairment (RI). Methods A total of 113 newly diagnosed patients with MM in the department of nephrology and hematology in Zhongnan Hospital of Wuhan University from January 2013 to December 2017 were enrolled. The patients were divided into RI group and non-renal impairment (NRI) group according to whether serum creatinine (Scr) at the time of diagnosis was higher than 177 μmol/L. The clinical and laboratory data of two groups were compared. The risk factors of RI in MM patients were analyzed by binary logistic regression, and then the receiver operating characteristic curve (ROC) was drawn to evaluate the predictive value of these risk factors. Results The incidence of RI in 113 MM patients was 34.5%. Compared with NRI group, levels of white blood cells, serum uric acid, blood urea nitrogen, neutrophil-to-lymphocyte ratio (NLR), cystatin C, β₂-microglobulin (β₂-MG), blood phosphorus, urine light chain, bone-marrow plasma cell percentage, International Staging System (ISS) stage III percentage, light chain type percentage, positive urinary Bence-Jones protein percentage and positive urinary protein percentage were higher in RI group, while levels of estimated glomerular filtration rate (eGFR), serum bicarbonate concentration and globulin were lower in RI group (all P<0.05). There were no significant differences in other clinical variables between the two groups (all P>0.05). Fluorescence in situ hybridization (FISH) was applied to 42 MM patients to detect the following five genetic abnormalities: IgH rearrangement, 1q21 amplification, RB1 deletion, D13S319 deletion and P53 deletion. Among them, 29 (69.0%) patients were abnormal. The incidence of RB1 deletion in RI group was higher than NRI group (P<0.05), and there were no significant differences in the incidences of other genetic abnormalities (all P>0.05). Further logistic regression analysis showed that increase of NLR (OR=1.589, 95%CI 1.115-2.266, P=0.010), bone-marrow plasma cell percentage (OR=1.053, 95%CI 1.008-1.101, P=0.021) and β₂-MG (OR=22.166, 95%CI 2.146-228.927, P=0.009), light chain type (OR=15.399, 95%CI 1.002-236.880, P=0.049), and hyperuricemia (OR=11.707, 95%CI 1.580-86.717, P=0.016) were the independent risk factors for RI in MM patients. The comparison of area under the ROC (AUC) among these risk factors showed the AUC of β₂-MG was larger than that of NLR or uric acid (both P<0.05), while there were no significant differences in the rest of pairwise comparison (all P>0.05). The AUC of β₂-MG predicting RI was the largest (AUC=0.907, 95%CI 0.853-0.962, P<0.001). Conclusions MM patients have high morbidity of RI, and there are more RI patients with RB1 deletion in RI patients. Light chain type, hyperuricemia, high level of NLR, high bone-marrow plasma cell percentage and increased β₂-MG are the independent risk factors for RI in MM patients. Among them, β₂-MG is the best predictor for RI, and NLR plays an important role in predicting RI as a convenient and effective inflammatory marker.

Objective To investigate whether Bruton's tyrosine kinase knockout (Btk^-/-) in macrophages attenuates diabetic kidney disease in the streptozotocin (STZ)-induced mice. Methods Macrophages-specific Btk^-/- mice and control mice (C57BL/6N) were randomly divided into WT group, diabetic group, Btk^-/- group and Btk^-/- diabetic group. The diabetic models were induced by STZ (50 mg/kg). After 12 weeks, relevant biochemical parameters and the histological changes of kidneys were detected. The expression of macrophages marker CD68 were detected by immunofluorescence, and the immunohistochemistry was employed to detect the expression of WT1 and Nephrin on renal podocytes. In addition, the expression of fibronectin (FN), collagen type IV (IV-Col), transforming growth factor-β1 (TGF-β1), iNOS, phospho (p)-Btk, interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), MAPK and NF-κB signaling pathway were detected by Western blotting. RT-PCR was used to detect the mRNA of IL-1β, TNF-α and monocyte chemotactic protein-1 (MCP-1). Results Compared with diabetic group, the mice in Btk^-/- diabetic group had reduced albuminuria and attenuated kidney histopathology significantly, significantly increased WT1 and Nephrin, significantly decreased expression of CD68, FN, IV-Col and TGF-β1, and these changes were correlated with decreased of renal inflammatory cytokines such as IL-1β, TNF-α, MCP-1 and down-regulating MAPK and NF-κB signaling pathway (all P<0.05). Conclusion Macrophages-specific Btk^-/- may protect the kidney of diabetic mice by reducing the expression of renal inflammatory cytokines in MAPK and NF-κB signaling pathway.

Objective To investigate the effects and underlying mechanisms of aspirin on endoplasmic reticulum stress in podocytes induced by hyperlipemia. Methods Cultured podocytes were divided into four groups: control group, aspirin (100 μg/ml) group, oxidized low density lipoprotein (ox-LDL, 100 μg/ml) group, aspirin+ox-LDL group. The expression of protein kinase R-1ike endoplasmic reticulum kinase (PERK), eukaryotic translation initiation factor 2α (eIF2α), activating transcription factor-4 (ATF4) and CAAT/enhancer binding protein homologous protein (CHOP) at 6 h, 12 h, 24 h, 48 h were evaluated by real-time PCR. The related proteins of p-PERK and p-eIF2α at 24 h and ATF4 at 12 h were evaluated by Western blotting, respectively. Results The expressions of PERK, eIF2α peaked at 24 h, while ATF4 and CHOP peaked at 12 h in ox-LDL group and aspirin+ox-LDL group. Compared with control group, the expressions of PERK, eIF2α, ATF4 and CHOP were significantly higher in ox-LDL group at each times (all P<0.05). Compared with ox-LDL group, the expressions of the above indicators were significantly lower in aspirin +ox-LDL group at each times (all P<0.05). At 24 h, compared with control group, the expressions of p-PERK and p-eIF2α were significantly higher in ox-LDL group (both P<0.05). Compared with ox-LDL group, the expressions of p-PERK and p-eIF2α were significantly lower in aspirin +ox-LDL group (both P<0.05). At 12 h, the expression of ATF4 protein in each group was similar to that of mRNA. There were no significant difference in the expressions of all indicators between aspirin group and control group. Conclusions Hyperlipidemia may cause endoplasmic reticulum stress in podocytes by inducing phosphorylation of PERK and eIF2α, activating ATF4 transcription and inducing high expression of CHOP. Aspirin may partially block the PERK pathway, which may have protective effects for podocytes.