Objective To clarify whether the NADPH oxidases (NOXs) family contributed to the reactive oxygen species (ROS) production and subsequent interstitial fibrosis in unilateral ureter obstruction (UUO) rats.Methods Male Wistar rats were randomly divided into sham operation group (n =8),sham operation + apocynin treatment group (n =8),UUO operation group (n =8) and UUO operation+apocynin treatment group (n =8).Either vehicle or apocynin (100 mg/kg per day) were given by gavage for 7 days after surgery.Rats were sacrificed at 7th day.ELISA was used to detect the activity of superoxide dismutase (SOD) and catalase (CAT),and the level of 8-iso-prostaglandin F2alpha (8-isoPGF2α) in renal tissue.Western blotting was used to detect the protein expressions of NADPH oxidase subunit NOX2 and NOX4,α-smooth muscle actin(α-SMA),collagen Ⅰ (COL-Ⅰ) and the level of ERK1/ 2 phosphorylation (p-ERK1/2).Results UUO rats with vehicle displayed increased oxidative stress,as measured by renal tissue 8-iso-PGF2α,accompanied with increased renal expression of NADPH oxidases (NOX2,1.5-fold and NOX4,1.7-fold,respectively),compared with sham-operated rats (P ＜0.05).Furthermore,vehicle treated UUO rats showed increased renal COL-Ⅰ and α-SMA levels,compared with sham-operated rats (P ＜ 0.05).ERK1/2 was also activated as detected by p-ERK1/2 expression in UUO rats with vehicle (P ＜ 0.05).Apocynin treatment significantly decreased renal tissue 8-iso-PGF2α level and expressions of NOX2 (-28.7％) and NOX4 (-31.0％) in UUO rats,respectively,compared with vehicle treated rats (P ＜ 0.05).And significant decrease of COL-Ⅰ (-26.4％) and α-SMA expression (-80.0％) were also observed (P ＜ 0.05).The activation of ERK1/2 in UUO rats was greatly inhibited by apocynin treatment (P ＜ 0.01).Despite the pronounced dysregulation of pro-oxidative NOXs family,no compensatory increase of antioxidative enzyme activities occurred.Conclusion The NOXs family contributes largely to the production of ROS and subsequent interstitial fibrosis after ureter ligation,and inhibition of the NOXs family may be a choice for preventing interstitial fibrosis.

Objective To investigate the effect of VPA and molecular hydrogen(H2)on phenotypes of microglia treated with hypoxia. Methods Mouse hypoxic BV2 microglia were treated with VPA or H2. The levels of phenotypic markers of supernatant and cells were detected by ELISA, flow cytometry and real?time PCR,respectively. Results Hypoxia significantly increased mRNA level of M1 marker(iNOS)and reduced mRNA levels of M2 markers(CD206 and TGF?β)in BV2(P<0.05). Besides,the ratio between the mRNA levels of M1 increased(P<0.05). VPA significantly reduced protein level(CD16/32)and mRNA production(iNOS)of M1 markers in hypoxia?treated BV2(P<0.05). The ratio be?tween the mRNA levels of M1 markers and M2 markers(CD16:CD206,CD32:CD206,iNOS:CD206 and iNOS:TGF?β)were also significantly decreased(P<0.05). H2 significantly reduced both protein levels(TNF?α,CD16/32 and iNOS)and mRNA production(iNOS)of M1 markers and increased secretion of M2 marker(IL?10)in hypoxia?treated BV2(P<0.05). The ratio between the mRNA levels of M1 markers and M2 markers(CD16:CD206,iNOS:CD206 and iNOS:TGF?β)were also highly declined(P<0.05). Conclusion Hypoxia can induce microglial cells toward pro?inflammatory phenotype. Both VPA and H2 can inhibit hypoxia?induced inflammatory effect on microglia.

Objective To analyze the effects of valproic acid(VPA),a histone deacetylase(HDAC)inhibitor,on macrophage polarization in?duced by paraquat(PQ)or lipopolysaccharide(LPS). Methods Mouse RAW264.7 cells were cultured at 37℃with 5%CO2,passaged,and then given one of the following treatments:(1)PQ;(2)PQ+VPA(classⅠandⅡa HDAC inhibitor);(3)PQ+apicidin(classⅠHDAC inhibitor);(4)PQ+MC1568(classⅡa HDAC inhibitor);(5)LPS;(6)LPS+VPA;(7)LPS+apicidin;(8)LPS+MC1568. The cells and culture supernatants were harvested after 8 h of treatment. RT?PCR,ELISA,and flow cytometry were conducted to assess the expression levels of macrophage phenotyp?ic markers. Results Both PQ and LPS skewed the macrophage functional polarity toward proinflammatory phenotype. VPA,apicidin,and MC1568 all inhibited PQ?and LPS?induced macrophages polarizing toward pro?inflammatory phenotype ,but the inhibitory effects were different in some ways. Conclusion VPA inhibits the proinflammatory function of macrophages induced by PQ and LPS ,but the effect of VPA on PQ?and LPS?induced macrophages has its own characteristics.

Objective To investigate the clinical features and prognostic risk factors of pneumocystis pneumonia (PCP) in patients with glomerular disease. Methods The medical charts of all patients with confirmed PCP, diagnosed in Peking University First Hospital from August 2006 to February 2018 were retrospectively reviewed, and 36 cases with glomerular disease were enrolled. Clinical and imaging data were collected and analyzed. Thirty-six patients were divided into survival group and death group. The clinical data, baseline estimated glomerular filtration rate (eGFR), mechanical ventilation and APACHE II score were compared. Results A total of 27 males and 9 females were included, with age of (49.6 ± 17.5) years. All patients were receiving immunosuppressive therapy at the PCP onset, with a median duration of 2.5 months, and none of them was receiving PCP prophylaxis. The main clinical manifestations included fever (100.0% ), dyspnea (75.0% ) and dry cough (61.1% ). Hypoxemia occurred in 97.2% of patients and 17 cases presented as type 1 respiratory failure. Fifteen out of 30(50.0%) patients had CD4+ T cell counts below 200 cells/mm3. Ground glass opacity was the most common finding in CT imaging of 28 patients, followed with grid shadows, consolidation and nodules. Thirty-five patients received trimethoprim-sulfamethoxazole (TMP-SMX) as initial therapy, and 17.1% (6/35) of them developed acute kidney injury due to sulfonamide use. Ten patients died during hospitalization, with respiratory failure as the only direct cause of death. Elder age, delayed diagnosis of PCP, mechanical ventilation and high APACHEⅡscores were associated with poor survival. Conclusions PCP is a severe complication of immunosuppressive therapy in patients with glomerular disease. Early diagnosis and prompt treatment are critical to improve prognosis. Hydration prior to sulfonamide treatment and alkalization of urine are necessary to reduce the incidence of acute kidney injury.

Objective To elucidate the clinical and pathological characteristics of the patients with thymoma-associated glomerulonephropathy.Methods In this retrospective study,the clinicopathologic characteristics of patients diagnosed as thymoma-associated glomerulonephropathy inPeking University First Hospital during the period between Oct 2008 and Jun 2017 were analyzed,including the histological classfication of thymoma,the clinicopathological features and the short-term prognosis.Results Altogether twelve patients were included with an average age of (55+ 16) years;male/female ratio was 3∶ 1.The B2 type thymoma was the most common type.Nine cases also suffered from myasthenia gravis,and eight cases of glomerulopathy accompanied by thymoma activity.The clinical presentation of glomerulopathy included nephrotic syndrome (11/12),acute kidney injury (10/12).Eleven patients received renal biopsy,among which five cases were minimal change nephropathy,three cases were membranous nephropathy,and the other three cases were focal segmental glomerulosclerosis,thrombotic microangiopathy and endocapillary proliferative glomerulonephritis,respectively.Eleven patients received immunosuppression therapy.After a median 12 months follow up,the proteinuria decreased in 7 cases,and renal function completely or partially recovered in 6 cases.Conclusions Minimal change disease is the most frequent pathological type of thymoma-associated glomerulonephropathy.Immunotherapy with glucocorticoid as first-line drug may be considered for thymoma-associated glomerulonephropathy with surgery,chemoradiation contraindications or non-remission of kidney disease after anti-tumor therapy.

As a new treatment option after conventional corticosteroids and immunomodulatory drugs, biologics have been widely used in the clinical management of non-infectious uveitis in many countries due to their approved efficacy and safety. Anti-tumor necrosis factor-alpha monoclonal antibody is the most commonly used one. However, the guidance on its standardized application is lacking. The Ocular Immunology Group of Immunology and Rheumatology Academy in Cross-Straits Medicine Exchange Association compiled the Chinese expert consensus on treatment of non-infectious uveitis with anti-tumor necrosis factor-alpha monoclonal antibody. This evidence-based consensus is made according to the principle of consensus building and combines the clinical experience of the experts. Twelve recommendations are formatted on the application of Adalimumab and Infliximab. The interpretation of this consensus point will help improve the normative and effective application of anti-tumor necrosis factor-alpha monoclonal antibody in ophthalmologists, rheumatologists and immunologists.

Objective:To explore the association of access blood flow measured by ultrasound dilution and color Doppler ultrasound with patency loss of arteriovenous fistula (AVF).Methods:This was a bidirectional cohort study. The adult patients who underwent maintenance hemodialysis (MHD) with AVF in Peking University First Hospital from January 1, 2018 to July 31, 2020 were enrolled. AVF blood flow was measured by ultrasonic dilution method (Qa), and color Doppler ultrasound in cephalic vein and brachial artery. Patients were divided into low Qa (<500 ml/min), normal Qa (500-1 500 ml/min) and high Qa (>1 500 ml/min) groups according to baseline AVF blood flow measured by ultrasonic dilution method. Qa was monitored every 3 months within the first year. The endpoint events of follow-up were defined as AVF patency loss or death. The deadline of the follow-up was July 31, 2022. Linear regression analysis was used to assess the change trend of Qa. Fine and Gray competitive risk model was used to evaluate the cumulative incidence of AVF patency loss. The Cox proportional hazards regression model was used to evaluate the association between access AVF blood flow and patency loss.Results:A total of 163 patients were enrolled, with age of (57.0±13.7) years old and 110 males (67.5%). The median follow-up time was 45(22, 53) months. Forty-four patients (27.0%) had AVF failure, and 29 patients (17.8%) died. The cumulative incidence rates of AVF patency loss in patients with low Qa, low blood flow of brachial artery and cephalic vein (<500 ml/min), and in those with a downward trend of Qa were higher than those in patients with normal or high blood flow, and in those with a upward trend of Qa (Gray′s test, all P<0.05). After adjusted for age, sex, age of fistula, diabetes and vascular stenosis, multivariable Cox regression analysis results showed that baseline Qa<500 ml/min ( HR=3.508, 95% CI 1.382-8.905, P=0.008), baseline brachial artery flow<500 ml/min ( HR=2.413, 95% CI 1.058-5.503, P=0.036) and a downward trend of Qa ( HR=2.498, 95% CI 1.241-5.027, P=0.010) were independently associated with AVF patency loss. Conclusions:Patients with low baseline value or downward trend of AVF blood flow are at significantly higher risk of patency loss. The brachial artery measurement of AVF blood flow is the preference location for color Doppler ultrasonic.

Objective:To investigate the urinary sediment findings and the clinicopathologic features of IgA nephropathy (IgAN) patients with acute kidney injury (AKI).Methods:It was a retrospective study. The patients with renal biopsy-proven primary IgAN in Peking University First Hospital from January 31, 2013 to July 31, 2015 were selected. According to whether AKI occurred at renal biopsy or not, the patients were divided into AKI group and non-AKI group. Morning urine samples were obtained on the day of renal biopsy. Urine sediments, including various cells and casts, were examined. The clinical data, urinary sediments, and renal pathological changes were compared between the two groups. Logistic regression analysis was performed to identify the association between clinical pathological changes, urinary sediment indicators and AKI, or clinical pathological changes and urinary sediment indicators.Results:There were 502 IgAN patients enrolled in this study, with age of (36.1±12.1) years old and 261 males (52.0%). The incidence of AKI was 11.4% (57/502) among the enrolled patients at the time of renal biopsy. Common causes of AKI included gross hematuria-induced AKI (10 cases), acute tubulointerstitial nephritis (10 cases), crescentic IgAN (9 cases), malignant hypertensive renal damage (6 cases), and multiple etioloqy or unknown etiology (22 cases). Compared with non-AKI group, AKI group had higher proportions of males and malignant hypertension, higher levels of proteinuria and urinary erythrocyte counts, and higher frequencies of gross hematuria, leukocyturia, renal tubular epithelial cells, and granular casts (all P<0.05). AKI group also had higher proportions of severe tubular atrophy/interstitial fibrosis (T2) and cellular/cellular fibrous crescent formation (C2) than non-AKI group (both P<0.05). Logistic regression analysis results showed that, there were statistically significant differences in the correlation between AKI and gender, 24 h urinary protein, urinary erythrocyte counts, granular casts and renal tubular atrophy/interstitial fibrosis (T) scores (all P<0.05). Hematuria, leukocyturia, red blood cell casts, white blood cell casts, granular casts, and fatty casts were correlated with endothelial hypercellularity (E) and cellular/cellular fibrous crescent formation (C) scores, respectively (all P<0.05). Hematuria was correlated with mesangial hypercellularity (M) scores ( OR=2.613, 95% CI 1.520-4.493, P=0.001). Hematuria ( OR=1.723, 95% CI 1.017-2.919, P=0.043) and fatty casts ( OR=2.646, 95% CI 1.122-6.238, P=0.026) were correlated with segmental sclerosis or adhesion (S) scores. Leukocyturia ( OR=1.645, 95% CI 1.154-2.347, P=0.006) and fatty casts ( OR=2.344, 95% CI 1.202-4.572, P=0.012) were correlated with T scores. Epithelial cell cast was correlated with C scores ( OR=1.857, 95% CI 1.174-2.939, P=0.008). Conclusions:AKI is a common complication among IgAN patients with diverse etiology and more severe clinicopathological features. Urinary sediment findings can reflect renal pathological changes to some extent, and therefore assist in the clinical diagnosis and treatment of IgAN patients with AKI.

Mechanistic target of rapamycin (mTOR) complex 1 (mTORC1) integrates signals from growth factors, cellular energy levels, stress and amino acids to control cell growth and proliferation through regulating translation, autophagy and metabolism. Here we determined the cryo-electron microscopy structure of human mTORC1 at 4.4 Å resolution. The mTORC1 comprises a dimer of heterotrimer (mTOR-Raptor-mLST8) mediated by the mTOR protein. The complex adopts a hollow rhomboid shape with 2-fold symmetry. Notably, mTORC1 shows intrinsic conformational dynamics. Within the complex, the conserved N-terminal caspase-like domain of Raptor faces toward the catalytic cavity of the kinase domain of mTOR. Raptor shows no caspase activity and therefore may bind to TOS motif for substrate recognition. Structural analysis indicates that FKBP12-Rapamycin may generate steric hindrance for substrate entry to the catalytic cavity of mTORC1. The structure provides a basis to understand the assembly of mTORC1 and a framework to characterize the regulatory mechanism of mTORC1 pathway.
Cell Line ; Cryoelectron Microscopy ; methods ; Humans ; Mechanistic Target of Rapamycin Complex 1 ; Multiprotein Complexes ; chemistry ; ultrastructure ; Protein Structure, Quaternary ; TOR Serine-Threonine Kinases ; chemistry ; ultrastructure

Transcription, Genetic