Complement system is overactivated in patients with IgA nephropathy after COVID-19.

IgA nephropathy (IgAN), which has been confirmed as a complement mediated autoimmune disease, is also one form of glomerulonephritis associated with COVID-19. Here, we aim to investigate the clinical and immunological characteristics of patients with IgAN after COVID-19. The level of plasma level of C5a (p < 0.001), soluble C5b-9 (p = 0.018), FHR5 (p < 0.001) were all significantly higher in Group CoV (33 patients with renal biopsy-proven IgAN experienced COVID-19) compared with Group non-CoV (44 patients with IgAN without COVID-19), respectively. Compared with Group non-CoV, the intensity of glomerular C4d (p = 0.017) and MAC deposition (p < 0.001) and Gd-IgA1 deposition (p = 0.005) were much stronger in Group CoV. Our finding revealed that for IgAN after COVID-19, mucosal immune responses to SARS-CoV-2 infection may result in the overactivation of systemic and renal local complement system, and increased glomerular deposition of Gd-IgA1, which may lead to renal dysfunction and promote renal progression in IgAN patients.

Synthesis and Antibacterial Activity of Novel Triazolo[4,3-a]pyrazine Derivatives.

Infectious diseases pose a major challenge to human health, and there is an urgent need to develop new antimicrobial agents with excellent antibacterial activity. A series of novel triazolo[4,3-a]pyrazine derivatives were synthesized and their structures were characterized using various techniques, such as melting point, 1H and 13C nuclear magnetic resonance spectroscopy, mass spectrometry, and elemental analysis. All the synthesized compounds were evaluated for in vitro antibacterial activity using the microbroth dilution method. Among all the tested compounds, some showed moderate to good antibacterial activities against both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli strains. In particular, compound 2e exhibited superior antibacterial activities (MICs: 32 µg/mL against Staphylococcus aureus and 16 µg/mL against Escherichia coli), which was comparable to the first-line antibacterial agent ampicillin. In addition, the structure-activity relationship of the triazolo[4,3-a]pyrazine derivatives was preliminarily investigated.

Two kinds of rare light chain cast nephropathy caused by multiple myeloma: case reports and literature review.

BACKGROUND: Light chain cast nephropathy (LCCN) is the most common renal disease caused by multiple myeloma (MM). In addition to ordinary light chain protein casts, there are a few rare casts with unique shapes, including light chain amyloid casts (LCAC) and light chain crystal casts (LCCC). CASE PRESENTATIONS: Here, we report two patients. Patient 1 is a 72-year-old man who was clinically diagnosed with MM and acute kidney injury (AKI). Pathological examination of a renal biopsy revealed that there were many amyloid casts in the distal tubules that had a lightly-stained central area and a deeply-stained burr-like edge. The marginal zone of the cast was positive for Congo red staining and contained numerous amyloid fibers, as observed by electron microscopy. No systemic amyloidosis was found. The patient received 4 courses of bortezomib-based chemotherapy, and then, his MM achieved partial remission. Patient 2 is a 57-year-old man who was also clinically diagnosed with MM and AKI. Pathological examination of a renal biopsy showed that there were many crystalline casts in the distal tubules that were fully or partially composed of crystals with different shapes, including rhomboid, needle, triangle, rectangle and other geometric shapes. Congo red staining was negative. Crystals were also detected in the urine of this patient. After 9 courses of treatment with a bortezomib-based regimen, his MM obtained complete remission and his renal function returned to normal. CONCLUSIONS: LCAC and LCCC nephropathy caused by MM are two rare types of LCCN, and both have their own unique morphological manifestations. LCAC nephropathy may not be accompanied by systemic amyloidosis. The diagnosis of these two unique LCCNs must rely on renal biopsy pathology, and the discovery of urine crystals is of great significance for indicating LCCC nephropathy.

Antineutrophil cytoplasmic antibody and/or antiglomerular basement membrane antibody associated crescentic glomerulonephritis in combination with IgG4-related tubulointerstitial nephritis.

OBJECTIVES: Immunoglobulin G4 (IgG4)-related disease (IgG4-RD) is an immune-mediated fibroinflammatory disorder and is characterised by elevated serum IgG4 concentrations and dense lymphoplasmacytic infiltrate rich in IgG4+ plasma cells. IgG4-related tubulointerstitial nephritis (IgG4-TIN) is the most common manifestation of IgG4-related kidney disease (IgG4-RKD). We report four cases of kidney injury with concurrent IgG4-TIN and crescentic glomerulonephritis confirmed by renal pathology. METHODS: The medical charts of four patients were reviewed to collect clinical and laboratory data at the time of diagnosis, treatment and outcomes after 6-36 months. Two of them are cases of IgG4-TIN with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), and the other two cases are rare IgG4-TIN with antiglomerular basement membrane (anti-GBM) glomerulonephritis coexistent with ANCA-positive serum. RESULTS: Compared with IgG4-TIN, IgG4-TIN combined with AAV or anti-GBM glomerulonephritis is less associated with other organ injuries, and the clinical manifestations, treatment effects and prognosis were consistent with that of crescentic glomerulonephritis. CONCLUSIONS: IgG4-TIN concurrent with anti-GBM glomerulonephritis and positivity in serum has more severe clinical features and a worse renal prognosis than IgG4-TIN coexistent with AVV.

CD36-Mediated Lipid Accumulation and Activation of NLRP3 Inflammasome Lead to Podocyte Injury in Obesity-Related Glomerulopathy.

Podocyte injury critically contributes to the pathogenesis of obesity-related glomerulopathy (ORG). Recently, lipid accumulation and inflammatory responses have been found to be involved in podocyte injury. This study is to explore their role and relationship in podocyte injury of ORG. In animal experiments, the ORG mice developed proteinuria, podocyte injury, and hypertriglyceridemia, accompanied with deregulated lipid metabolism, renal ectopic lipid deposition, activation of NOD-like receptor protein 3 (NLRP3) inflammasome, and secretion of IL-1ß of the kidney. The expression of adipose differentiation-related protein (ADRP), CD36, sterol regulatory element-binding protein 1 (SREBP-1), and peroxisome proliferator-activated receptor α (PPARα) in renal tissue were increased. In in vitro cell experiments, after cultured podocytes were stimulated with leptin, similar to ORG mice, we found aggravated podocyte injury, formatted lipid droplet, increased expression of ADRP and CD36, activated NLRP3 inflammasome, and released IL-1ß. In addition, after blocking CD36 with inhibitor sulfo-N-succinimidyl oleate (SSO) or CD36 siRNA, activation of NLRP3 inflammasome and release of IL-1ß are downregulated, and podocyte injury was alleviated. However, after blocking NLRP3 with MCC950, although podocyte injury was alleviated and release of IL-1ß was decreased, there was no change in the expression of CD36, ADRP, and intracellular lipid droplets. Taken together, our study suggests that CD36-mediated lipid accumulation and activation of NLRP3 inflammasome may be one of the potential pathogeneses of ORG podocyte injury.

Corrigendum to "CD36-Mediated Lipid Accumulation and Activation of NLRP3 Inflammasome Lead to Podocyte Injury in Obesity-Related Glomerulopathy".

[This corrects the article DOI: 10.1155/2019/3172647.].

Ultrahigh Performance Liquid Chromatography-Electrospray Ionization Tandem Mass Spectrometry Method for Qualitative and Quantitative Analyses of Constituents of Corydalis bungeana Turcz Extract.

In this study, the constituents of a Corydalis bungeana Turcz extract were qualitatively analyzed using gradient elution with a mobile phase of 0.2% acetic acid and acetonitrile. We obtained comprehensive insight into the constituents of C. bungeana Turcz extracts through the quantitative analysis of 14 compounds by comparison with authentic reference standards, and tentatively identified an additional 44 compounds through electrospray ionization mass spectrometry (ESI-MS) and tandem MS detection. The separation was successfully achieved using an Agilent SB-C18 column (1.8 µm, 150 × 2.1 mm; Agilent, Santa, CA, USA). A tandem quadrupole spectrometer was operated in either full-scan mode or multiple reaction monitoring (MRM) for the qualitative and quantitative analyses of the constituents, respectively. Validation data (inter-day and intra-day combined) for accuracy and precision ranged from -4.80% to 4.73%, and 0.30% to 4.97%, respectively. An ultrahigh performance liquid chromatographic-ESI-tandem MS (UHPLC-ESI-MS/MS) method for qualitative of C. bungeana Turcz (C. bungeana) extract and the quantification of 14 alkaloids, namely, A-N, was developed and validated. Quantitative analysis involved gradient elution with a mobile phase of 0.1% acetic acid and methanol for 45 min. The separation was successfully achieved using a Waters SB-C18 column (1.8 µm, 100 mm × 2.1 mm, Waters, Milford, Massachusetts, USA). The repeatability and stability of the method also met USFDA criteria with CV values lower than 5%. The limit of detection of the 14 alkaloids ranged from 9.74 to 13.00 ng/mL, whereas the linearities of the standard curves were between 0.9991 and 0.9995. In total, 15 commercial samples from 11 different sources were analyzed.

An Ultra-High Performance Liquid Chromatography with Tandem Mass Spectrometry Method for Determination of 10 Alkaloids in Beagle Dog Plasma after the Oral Administration of the Corydalis yanhusuo W.T. Wang Extract and Yuanhuzhitong Tablets.

This study has developed a sensitive and simple ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometry method for the simultaneous determination of corydaline, dehydrocorydaline, tetrahydropalmatine, protopine, palmatine, tetrahydroberberine, columbamine, berberine, coptisine and berberrubine in beagle dog plasma after the oral administration of the Corydalis yanhusuo W.T. Wang and Yuanhuzhitong tablets. Chromatographic separation was achieved on an Agilent Eclipse Plus C18 RRHD column (1.8 µm, 50 × 2.1 mm) using a gradient elution program with a mobile phase consisting of acetonitrile and water containing 0.1% formic acid at a flow rate of 0.3 mL/min. A tandem mass spectrometric detection was conducted by multiple reaction monitoring (MRM) mode via an electrospray ionization source in the positive mode. The calibration curves of all analytes showed good linear (r² > 0.9800). The intra-day and inter-day precisions were less than 15% and the accuracies were within ±15%. The extraction recoveries conformed to the acceptable range. And there was no interference of endogenous substances in the sensitive assay method. All analytes were proven to be stable during sample storage and analysis procedures. The pharmacokinetic study indicated that the Yuanhuzhitong tablets could get a better absorption than Corydalis yanhusuo W.T. Wang.

Liquid Chromatography-Tandem Mass Spectrometry Simultaneous Determination and Pharmacokinetic Study of Fourteen Alkaloid Components in Dog Plasma after Oral Administration of Corydalis bungeana Turcz Extract.

A rapid and sensitive Ultra high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed for the simultaneous determination of fourteen alkaloids in beagle dog plasma after a single oral dose of the Corydalis bungeana Turcz (C. bungeana) extract selected bifendate as the internal standard (IS). The plasma samples were preprocessed by liquid-liquid extraction (LLE) with aether before separation on an Agilent SB-C18 column (1.8 µm, 150 × 2.1 mm) using a gradient elution program. The mobile phase consists of 0.2% acetic acid and acetonitrile at the flow rate of 0.3 mL/min. In the positive ion mode, the analytes were detected by multiple reaction monitoring (MRM). The results indicated that calibration curves for fourteen analytes have good linearity (R² = 0.9904). The lower limits of quantification (LLOQ) of fourteen alkaloids and IS were all over 4.87 ng/mL and the matrix effects ranged from 94.08% to 102.76%. The mean extraction recoveries of Quality control samples at low (LQC), medium (MQC) and high (HQC) and IS were all more than 78.03%. The intra- and inter-day precision (R.S.D.%) also met the criterion, at the same time the deviation of assay accuracies (R.E) ranged from -13.70% to 14.40%. The Tmax values of fourteen alkaloids were no more than 1 h. The range of Cmax was from 74.16 ± 8.71 to 2256 ± 255.9 ng/mL. The assay was validated in the light of the regulatory bioanalytical guidelines and proved acceptable, which was successfully applied to a pharmacokinetic study of these compounds in beagle dogs after oral administration of Corydalis bungeana Turcz extract.

Simultaneous Determination and Pharmacokinetics Study of Six Triterpenes in Rat Plasma by UHPLC-MS/MS after Oral Administration of Sanguisorba officinalis L. Extract.

A selective and sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated for the determination of ziyuglycoside I (I), 3ß,19α-dihydroxyurs-12-en-28-oic-acid 28-ß-d-glucopyranosyl ester (II), 3ß-[(α-l-arabinopyranosyl) oxy]-urs-12,18(19)-dien-28-oic acid ß-d-glucopyranosyl ester (III), rosamultin (IV), 1ß-hydroxyeuscaphic acid (V) and alpinoside (VI) in rats after oral administration of Sanguisorba officinalis L. (S. officinalis) extract. The 3ß,19α-dihydroxyurs-12-en-28-oic-acid 28-ß-d-glucopyranosyl ester, 3ß-[(α-l-arabinopyranosyl) oxy]-urs-12,18(19)-dien-28-oic acid ß-d-glucopyranosyl ester, rosamultin, 1ß-hydroxyeuscaphic acid and alpinoside in rat plasma were the first report in the pharmacokinetics study in the present study. The analytes were quantified using the multiple reaction monitoring (MRM) mode with the electrospray ion source in positive electrospray ionization. Plasma was extracted with ethyl acetate via liquid⁻liquid extraction. Bifendate was used as internal standard (IS). The current method was validated for linearity, intra-day and inter-day precisions, accuracy, extraction recovery, matrix effect and stability. The lower limits of quantification of ziyuglycoside I, 3ß,19α-dihydroxyurs-12-en-28-oic-acid 28-ß-d-glucopyranosyl ester, 3ß-[(α-l-arabinopyranosyl) oxy]-urs-12,18(19)-dien-28-oic acid ß-d-glucopyranosyl ester, rosamultin, 1ß-hydroxyeuscaphic acid and alpinoside were 6.1, 4.9, 1.3, 3.8, 1.5 and 5.7 ng/mL, respectively. Intra-day and inter-day precision and the accuracy of the assay were in range from -9.48 to 12.74%. The extraction recoveries of analytes and bifendate (IS) from rat plasma ranged from 77.17% to 92.48%. Six compounds could be rapidly absorbed into blood (Tmax, 0.58⁻1.58 h), and then eliminated relatively slowly (t1/2, 6.86⁻11.63 h). The pharmacokinetic results might contribute to further guide the clinical application of S. officinalis.

[Application of Immunohistochemistry and Immunofluorescence Staining in Detection of Phospholipase A2 Receptor on Paraffin Section of Renal Biopsy Tissue].

OBJECTIVE: To evaluate the application of immunohistochemistry and fluorescence staining method in the detection of phospholipase A2 receptor (PLA2R) on paraffin section of renal biopsy tissue,and to find an accurate and fast method for the detection of PLA2R in renal tissue. METHODS: The PLA2R of 193 cases were detected by immunohistochemical staining,and the antigen was repaired by the method of high pressure cooker (HPC) hot repair plus trypsin repair. The 193 samples including 139 cases of idiopathic membranous nephropathy (IMN), 15 cases of membranous lupus nephritis, 8 cases of hepatitis B virus associated membranous nephropathy, 18 cases of IgA nephropathy, and 13 cases of minimal change diseases. To compare the dyeing effects, 22 paraffin sections of renal biopsy tissue of IMN cases with positive PLA2R were stained by using 4 different. METHODS: of antigen repairing,which included HPC hot repair, HPC hot repair plus trypsin repair, water bath heat repair, and water bath heat repair plus trypsin repair. To compare the dyeing effects, 15 paraffin sections of renal biopsy tissue of IMN cases with positive PLA2R were stained by using 3 different. METHODS: of antigen repairing,which included water bath heat repair plus trypsin repair, protease K digestion repair, and pepsin digestion repair. RESULTS: In 193 cases, the positive rate of PLA2R in IMN cases was 90.6% (126/139), and the other 54 patients without IMN were negative. Twenty-two IMN patients were positive for PLA2R by using the HPC heat repair plus trypsin repaire or the water bath heat repair plus trypsin repair;while only a few cases of 22 IMN cases were positive by using the HPC hot repair alone or water bath heat repair alone. Fifteen IMN patients were positive for PLA2R by using water bath heat repair plus trypsin repair,protease K digestion repair,and pepsin digestion repair, but the distribution of positive deposits and the background were different. CONCLUSIONS: PLA2R immunohistochemical staining can effectively identify IMN and secondary MN. For immunohistochemical staining and immunofluorescence staining, the preferred method of antigen repair is water bath heat repair plus trypsin repair.

Experimental Investigation into the Preparation Process of Graphene-Reinforced Aluminum Matrix Composites by Friction Stirring Processing.

Graphene has been considered an ideal reinforcement in aluminum alloys with its high Young's modulus and fracture strength, which greatly expands the application range of aluminum alloys. However, the dispersion of graphene and the interfacial reaction between graphene and the aluminum matrix limit its application due to elevated temperature. Friction stirring processing (FSP) is regarded as a promising technique to prepare metal matrix composites at lower temperatures. In this paper, FSP was used to prepare graphene-nanoplates-reinforced aluminum composites (GNPs/Al). The corresponding effects of the process parameters and graphene content on GNPs/Al were thoroughly studied. The results showed that plastic strain, heat input, and graphene content were the key influencing factors. Large degrees of plastic strain can enhance the dispersion of graphene by increasing the number of stirring passes and the ratio of stirring to welding velocity, thereby improving the strength of GNPs/Al. Low heat input restricts the plastic flow of graphene in the matrix, whereas excessive heat input can promote interfacial reactions and lead to the formation of a more brittle phase, Al4C3. This is primarily associated with the stirring velocity and welding velocity. High graphene content levels can improve the material strength by refining the grain size, improving the load transfer ability, and acting as a precipitate to prevent dislocation movement. These findings make a contribution to the development of advanced aluminum alloys with graphene reinforcement, offering broader application potential in industries.

Analysis of Clinicopathological Characteristics of Malignancy Patients with Membranous Nephropathy and Literature Review.

Purpose: In recent years, the incidence of malignancy patients with membranous nephropathy (MN) has gradually increased, but the clinical and pathological characteristics of these patients are still unclear. Our study aims at elucidating the clinical and pathological characteristics of malignancy patients with MN, especially the expression patterns of MN-specific antigens in both kidney and tumor tissue. Patients and Methods: A retrospective analysis was performed to summarize the clinical and pathological data of MN patients with malignancy at Beijing Anzhen Hospital from January 1, 2012, to December 31, 2022, followed by a thorough review of relevant literature published between May 1, 2000 to May 1, 2023 and case aggregation. Results: 19 patients in our center's MN cohort and 21 patients from literature review were diagnosed with malignancy either before or after being diagnosed with MN. Among them, 16 (40.0%) and 17 (42.5%) patients tested PLA2R-only and THSD7A-only positive in renal tissue, respectively. And 16 of 26 patients showed similar staining in tumor and kidney tissues. Compared to the idiopathic membranous nephropathy (IMN) patients at our center, patients with malignancy were older, had a lower estimated glomerular filtration rate, and had a lower rate of partial or complete response to treatment. Renal tissue from MN patients with concomitant malignancy was less frequently PLA2R-positive, more frequently THSD7A-positive, and more often glomerular IgG subclass IgG2 (P = 0.033) but less frequently IgG4 (P < 0.001). Conclusion: The clinical and pathological characteristics of MN patients with concomitant malignancy are different from those of IMN patients. Active screening for malignancy should be performed in non-PLA2R-positive elderly MN patients with a poor therapeutic response. Staining for MN target antigens in kidney and tumor tissues may be inconsistent, and the role of MN target antigens needs to be further explored.

An ultra-high-performance liquid chromatography-tandem mass spectrometry method for the simultaneous quantitation of 10 alkaloids of Corydalis Decumbentis Rhizoma preparation in dog plasma and its application to a pharmacokinetic study.

OBJECTIVE: A sensitive and rapid ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was successfully applied to the determination of 10 alkaloids in beagle dog plasma following a single oral dose of Xiatianwu capsules and enteric-coated capsules, with theophylline serving as the internal standard (IS). METHODS: Plasma samples were preprocessed using liquid-liquid extraction (LLE) with ethyl acetate ahead to separation using a gradient elution procedure on a Waters ACQUITY UPLC HSS T3 column (1.8 µm, 100 × 2.1 mm). The mobile phase was composed of 0.1% formic acid solution and acetonitrile at the flow rate of 0.3 ml/min. Multiple reaction monitoring (MRM) was used to determine the analytes in the positive ion mode. RESULTS: The calibration curves for 10 analytes demonstrated a high degree of linearity (r ≥ 0.9920). The lower limit of quantification (LLOQ) values for 10 alkaloids were all more than 1.074 ng/ml, and matrix effects varied from 94.25% to 106.15%. The mean extraction recovery of quality control samples at low (LQC), medium (MQC) and high (HQC) concentrations, as well as IS, was all more than 76.60%. The intra-day and inter-day precision (RSD) also satisfied the requirement. Simultaneously, the variation of assay accuracies (RE) was between 13.05% and 9.38%. CONCLUSION: The test was validated in accordance with regulatory bioanalytical guidelines and was found to be suitable for use in a pharmacokinetic investigation of these compounds in beagle dogs after oral administration of Xiatianwu general capsules and enteric-coated capsules. The Cmax of 10 alkaloids ranged from 52.61 to 192.46 ng/ml after oral administration of Xiatianwu capsules, and from 67.50 to 247.36 ng/ml. The Tmax was between 0.59 and 1.33 h of Xiatianwu capsules, and between 1.08 and 2.00 h of enteric-coated capsules. The t1/2 ranged from 3.18 to 7.47 h of general capsules, and from 6.01 to 11.36 h. AUC0-t ranged from 181.06 to 722.74 ng·h/ml of Xiatianwu capsules, and from 275.03 to 884.17 ng·h/ml of enteric-coated capsules. The Cmax of enteric-coated capsules were significantly increased except for tetrahydropalmatine and berberine. Tmax of general capsules were less than 1 h, and of enteric-coated capsules were less than 2 h. The t1/2 of dehydrocorydaline, palmatine, tetrahydrojatrorrhizine, jatrorrhizine and coptisine in enteric-coated capsules was longer than that in ordinary capsule. The AUC0-t and AUC0-∞ of bicuculline, dehydrocorydaline, protopine, magnoflorine, tetrahydrojatrorrhizine, jatrorrhizine, berberine and coptisine were all significantly higher in enteric-coated capsules.

Modeling of Eyld2000-2d Anisotropic Yield Criterion Considering Strength Differential Effect and Analysis of Optimal Calibration Strategy.

Sheet metals usually experience various loading paths such as uniaxial tension, uniaxial compression, biaxial tension, and simple shear during the forming process. However, the existing constitutive models cannot always accurately describe blanks' anisotropic yield and plastic flow behavior of blanks under all typical stress states. Given this, this paper improves the Eyld2000-2d yield criterion by introducing hydrostatic pressure to the A-Eyld2000-2d yield criterion that can describe the strength differential effect of materials. Meanwhile, to control the curvature of the yield surface more effectively, the near-plane strain yield stresses were added in the parameter identification process to calibrate the exponent m, so that the exponent is no longer considered as a constant value. Taking the widely used AA6016-T4, AA5754-O, DP980, and QP980 blanks in the automotive stamping industry as an example, the effectiveness of the new model and different parameter identification methods was verified by predicting experimental data under various simple and complex loading paths. Subsequently, the new model employing the optimal parameter identification strategy was compared with four widely used asymmetric yield criteria under associated and non-associated flow rules, including CPB06, LHY2013, S-Y2004, and Hu & Yoon2021, to further verify the accuracy of the proposed constitutive model. The results indicate that parameter identification strategy with variable exponent can significantly improve the flexibility of the yield criterion in describing the plastic anisotropy of blanks. Compared to the other yield criteria examined in this work, the new model provides the best prediction accuracy for the yield stresses and plastic flows of all blanks, especially in the near-plane strain and simple shear stress states. Modeling under the concept of anisotropic hardening can more accurately capture the evolving plastic behavior of blanks than isotropic hardening.

Clinicopathological and prognostic characteristics of idiopathic membranous nephropathy with dual antigen positivity.

Background: Idiopathic membranous nephropathy (IMN) is the most common pathological type in adults with nephrotic syndrome. Many target antigens have been discovered. However, dual antigen-positive IMN patients are very rare, with only a few such cases being briefly described in various studies. There is no specific study on the clinicopathological and prognostic characteristics of dual antigen-positive IMN patients, and the disease characteristics of such patients remain unclear. Methods: Immunohistochemical staining of PLA2R, THSD7A, and NELL-1 was conducted on kidney tissue samples obtained from patients diagnosed with IMN. Simultaneously, the presence of corresponding serum antibodies was determined. Patients exhibiting positivity for dual antigens were included in the study, identified either through tissue staining or serum antibody detection. We retrospectively collected their clinical, pathological, and follow-up data and measured their serum antibody levels at multiple time points. Additionally, the same type of dual antigen-positive IMN cases reported in the literature were reviewed to extract clinical, pathological, and prognostic information. We compared the data for all of the above dual antigen-positive and PLA2R single-positive IMN cases at our center. Results: We identified 6 IMN patients with dual antigen positivity at our center, approximately 0.7% of whole MN series; the previous literature reports 43 IMN patients with dual antigen positivity, the proportion ranged from 0.2% to 2.8%. The IgG1 positivity rate in the renal tissue of the dual antigen-positive patients at our center was significantly lower than that of dual antigen-positive patients previously reported (16.7% vs. 100.0%, p=0.015), but there was no significant difference in clinical or prognostic aspects. Patients with dual antigen positivity reported at our center and in the literature were combined and compared with PLA2R single-positive IMN reported at our center. Compared with PLA2R single-positive IMN patients, dual antigen-positive IMN patients had a higher renal tissue IgG1 positivity rate (58.3% vs. 22.3%, p=0.016), and the time required to achieve remission was longer [13.5 (3.3,35.0) vs. 3.0 (1.0,8.0), p=0.052]. Overall, The changes in urine protein were consistent with the changes in serum PLA2R antibody levels in dual antigen-positive IMN patients. Conclusions: For patients with primary membranous nephropathy who did not attain remission following prolonged treatment, multiple target antigen staining should still be actively performed, even with positivity for the PLA2R target antigen.

Characterization of patients with IgA nephropathy with and without associated minimal change disease.

Introduction: Immunoglobulin A nephropathy (IgAN) presents various clinical manifestations and pathological phenotypes. Approximately 5% of patients with IgAN present with early onset nephrotic syndrome, mild mesangial lesions, and diffuse foot process effacement of podocytes, which resemble minimal change disease (MCD). These patients are defined as MCD-IgAN. Whether MCD-IgAN is a special type of IgAN or simply MCD accompanied by IgA deposition remains controversial. Methods: A total of 51 patients diagnosed with MCD-IgAN at Beijing Anzhen Hospital from January 2010 to September 2022 were recruited. The clinical and pathological characteristics of IgA-MCD were analyzed. Patients with IgAN but without MCD (non-MCD-IgAN) and healthy participants were enrolled as controls. Galactose-deficient immunoglobulin A1 (Gd-IgA1) and complement C3 were detected both in the circulation and in renal tissues. Results: We found that the levels of serum Gd-IgA1 were lower in participants with MCD-IgAN than in those with non-MCD-IgAN, but higher than in healthy participants. Gd-IgA1 was rarely deposited in the glomeruli of participants with MCD-IgAN, with a positive rate of only 13.7% (7/51); in contrast, the positive rate in participants with non-MCD-IgAN was 82.4% (42/51). Among renal Gd-IgA1-positive patients, Gd-IgA1 and immunoglobulin A (IgA) colocalized along the glomerular mesangial and capillary areas. Interestingly, we found that the circulating levels of complement C3 were significantly higher in participants with MCD-IgAN than in participants with non-MCD-IgAN. In addition, the intensity of C3c in glomeruli in participants with MCD-IgAN was significantly weaker than in participants with non-MCD-IgAN. Conclusions: Our study suggests that, in MCD-IgAN, most of the IgA that is deposited on glomeruli is not the same pathogenic Gd-IgA1 as found in general IgAN. Complement activation both in the circulation and in the renal locality was much weaker in MCD-IgAN than in non-MCD-IgAN. Our study suggests that IgAN with MCD might be MCD with coincidental IgA deposition.

Determination of normal value of glomerular size in Chinese adults by different measurement methods.

AIM: Identification of glomerulomegaly is a prerequisite for diagnosis of obesity-related glomerulopathy, so measurement of glomerular size is of critical importance. METHODS: A total 100 cases pathologically diagnosed as minor glomerular abnormalities or thin basement membrane nephropathy with normal body mass index and blood glucose level were selected as the normal value measurement group of glomerular size. The mean value of diameters of capillary tuft on the glomerular maximum profile was determined using the direct method and indirect method with the Motic Med 6.0 digital medical image analysis system. Meanwhile, 80 cases of different glomerular disease with normal body mass index and blood glucose level were also collected. Their glomerular diameters were measured and compared with those in the normal value measurement group. RESULTS: The measurement results showed that gender and age had no effects on glomerular diameter. The normal value ranges of the diameter on glomerular maximum profile were as follows. (i) Pole-containing glomerulus (the glomerulus with vascular pole or/and urinary pole): direct method, 101.3-184.9 µm; indirect method, 100.3-183.5 µm. (ii) Pole-containing glomerulus plus non-pole glomerulus (the glomerulus without poles, the maximum profile of which was larger than that in the smallest pole-containing glomerulus): direct method, 108.3-185.9 µm; indirect method, 107.4-185.4 µm. The glomerular diameters of the 80 cases with different glomerular disease were all within the aforementioned normal value ranges. CONCLUSIONS: Both methods used in the present study are feasible to measure the glomerular diameter and the normal value range of glomerular diameter in Chinese adults is established.

Deep Learning Models for SO2 Distribution in a 30 MW Boiler via Computational Fluid Dynamics Simulation Data.

The distribution of SO2 in a boiler is an important factor affecting tube corrosion in a furnace. To investigate the correlation between SO2 distribution and numerous variables (e.g., temperature, O2 distribution, etc.), a hybrid deep learning model is developed via the computational fluid dynamics (CFD) simulation data. First, the combustion process under typical working conditions is simulated to output the training data set. Then, a LASSO algorithm is adopted to select input variables with a high correlation with SO2 distribution. Finally, a deep belief network combined with a restricted belief machine and a fully connected layer is developed to describe the nonlinear relationship. The proposed model is the first work to use a deep learning algorithm to obtain the correlation between SO2 distribution and other products of combustion. The results show that O2 concentration has the highest influence on SO2 distribution.