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Objective To explore lipid signatures of renal tissue in acute kidney injury （AKI） and AKI-to-CKD transition by untargeted lipidomics. Methods Ischemia-reperfusion injury （IRI） mice were subjected to bilateral renal pedicle clamping for 30 min. A murine model was established for longitudinally examining CKD progression after AKI and analyzing renal lipid metabolites by ultra-high performance liquid chromatography-tandem mass spectrometry. Results The levels of serum creatinine （Scr） and blood urea nitrogen （BUN） were significantly elevated after IRI and acute tubular injury score rose obviously at Day 2 post-IRI. The levels of Scr and BUN declined at Day 14/28 post-IRI and yet failed to completely return to baseline with severe renal interstitial fibrosis. A total of 1715 lipid metabolites were identified. Marked differences existed in renal lipid metabolic profiles between IRI and sham-operated mice at the corresponding timepoint. And there were also distinct lipids characteristic among IRI groups. In AKI stage, renal neutral lipid accumulation was most pronounced. In AKI-to-CKD transition stage, the most distinguished features of lipid profile were changes of glycerophospholipids and Sphingolipids. At Day 28 post-IRI, the number of decreased glycerophospholipid was more than increased glycerophospholipid. The most pronounced increase of alkenyl （vinyl） ether-phosphatidylethanolamine and the most pronounced decrease of phosphatidylglycerol occurred at Day 28 post-IRI. KEGG pathway enrichment also indicated glycerophospholipid metabolism was a predominant pathway during AKI-to-CKD transition. Conclusion Our study has revealed renal lipid signatures in the whole process of AKI to CKD transition. Glycerophospholipid, especially alkenyl（vinyl） ether-phosphatidylethanolamine and phosphatidylglycerol, might be an important lipid involved in AKI to CKD transition. It may facilitate the future study of pathogenesis and mechanism involved in AKI-to-CKD transition.

Abstract Mitochondrial dysfunction and impaired Ca2+ handling are involved in the development of diabetic cardiomyopathy (DCM). Dynamic relative protein 1 (Drp1) regulates mitochondrial fission by changing its level of phosphorylation, and the Orai1 (Ca2+ release-activated calcium channel protein 1) calcium channel is important for the increase in Ca2+ entry into cardiomyocytes. We aimed to explore the mechanism of Drp1 and Orai1 in cardiomyocyte hypertrophy caused by high glucose (HG). We found that Zucker diabetic fat rats induced by administration of a high-fat diet develop cardiac hypertrophy and impaired cardiac function, accompanied by the activation of mitochondrial dynamics and calcium handling pathway-related proteins. Moreover, HG induces cardiomyocyte hypertrophy, accompanied by abnormal mitochondrial morphology and function, and increased Orai1-mediated Ca2+ influx. Mechanistically, the Drp1 inhibitor mitochondrial division inhibitor 1 (Mdivi-1) prevents cardiomyocyte hypertrophy induced by HG by reducing phosphorylation of Drp1 at serine 616 (S616) and increasing phosphorylation at S637. Inhibition of Orai1 with single guide RNA (sgOrai1) or an inhibitor (BTP2) not only suppressed Drp1 activity and calmodulin-binding catalytic subunit A (CnA) and phosphorylated-extracellular signal-regulated kinase (p-ERK1/2) expression but also alleviated mitochondrial dysfunction and cardiomyocyte hypertrophy caused by HG. In addition, the CnA inhibitor cyclosporin A and p-ERK1/2 inhibitor U0126 improved HG-induced cardiomyocyte hypertrophy by promoting and inhibiting phosphorylation of Drp1 at S637 and S616, respectively. In summary, we identified Drp1 as a downstream target of Orai1-mediated Ca2+ entry, via activation by p-ERK1/2-mediated phosphorylation at S616 or CnA-mediated dephosphorylation at S637 in DCM. Thus, the Orai1–Drp1 axis is a novel target for treating DCM.

Abstract Background The establishment of apicobasal polarity in epithelial cells is of critical importance in morphogenesis of mammary gland and other secretive gland tissues. The demise of the polarity is a critical step in early stages of tumorigenesis such as in breast ductal carcinoma in situ. The underlying molecular mechanism thus warrants in-depth investigations. Results Protein kinase C isoform ζ (PKCζ), which is highly expressed in breast cancer cells, accumulates in the nuclei of human mammary epithelial cells overexpressing human rhomboid family-1 (RHBDF1), an endoplasmic reticulum membrane protein. Nuclear translocation of PKCζ results in the failure of the formation of the cytosolic apicobasal polarity complex Par, of which PKCζ is an essential component. Additionally, enhanced nuclear translocation of PKCζ is accompanied by an inhibition of the expression of cell tight junction and adherens junction proteins and an increase of cell mobility. Mechanistically, RHBDF1 is able to interact with importin β1 and PKCζ and promote PKCζ phosphorylation. Consistently, treatment of RHBDF1-overexpressing cells with an inhibitor of PKCζ phosphorylation leads to restoration of apicobasal polarity and cell-cell junctions, as well as suppressed cell mobility. Conclusions RHBDF1-facilitated nuclear translocation of PKCζ is critically responsible for the dismantlement of epithelial cell apicobasal polarity, and thus may serve as a target in the development of therapeutic approaches against early stages of breast cancer.

To deeply explore and develop their nutritive values and functions, the proteins and metal elements in two kinds of Macrocybe lobayensis (ML), TG505 and Grand Canyon ML were determined and analyzed. Protein fingerprints were obtained using phenol extraction and two-dimensional electrophoresis (2DE), and highly expressed proteins were selected. The enzymatic hydrolysates of highly expressed proteins were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Functional analysis of these proteins was carried out using bioinformatics tools. The contents of metal elements in the two kinds of mushrooms were determined by inductively coupled plasma mass spectrometry (ICP-MS). The results showed that 33 highly expressed proteins were identified from each kind of ML, which were involved in the growth, development, genetics, stress resistance, stress response, pharmaceutical activity and other functions of ML. For both kinds of ML, the major metal elements were K, Mg, Mo, Ca, Al, and Fe in decreasing order. The present study not only provides guidance for further exploitation and utilization of ML, with both medicinal and culinary uses, but also is of reference significance for the research and development of tropical edible mushrooms in Hainan.

Background and purpose: Radiotherapy is an important means to treat pelvic tumors. It is important to improve the accuracy of radiotherapy and enhance the effectiveness. This study aimed to compare and analyze the influence of positioning errors during the radiotherapy of patients using surface guided radiotherapy (SGRT) automatic positioning versus traditional surface marking positioning. Methods: We performed a retrospective analysis of 50 patients with pelvic tumors who received radiotherapy and had simple positioning fixation methods at the Fudan University Shanghai Cancer Center from April 2023 to April 2024. A total of 25 patients were treated using SGRT (observation group), and 25 patients were treated using traditional surface marking (control group). After positioning according to the two positioning techniques, cone beam computed tomography (CBCT) images were collected. These data were compared with the initial reference computed tomography (CT) images within 6 dimensions. The correction error values of the six dimensions were recorded. We calculated the averages, standard deviations, and the number of cases and probabilities in different interval distributions. SPSS 27.0 was used to perform statistical analysis of the data from the two groups of patients. We also analyzed the correlation of patients in the observation group within the 6 dimensions. Results: The non-parametric test showed significant differences in only the LNG and PITCH directions (P

Southern blight is a common and devastating disease adversely affecting the yield and quality of cultivated Dendrobium officinale plants. The pathogens responsible for this disease are Sclerotium delphinii and S. rolfsii, although S. delphinii is more pathogenic than S. rolfsii. Plant endophytes are potential sources of biological control agents. In this study, 18 microbial strains were isolated from wild Dendrobium shixingense plants (e.g., Streptomyces, Bacillus, and Trichoderma), among which strain MEPF0303 significantly inhibited S. delphinii mycelial growth. Based on 16S rRNA gene sequence, this strain was identified as Streptomyces sp. In addition, the volatile organic compounds and cell-free supernatant of MEPF0303 had significant inhibitory effects on S. delphinii growth. Moreover, MEPF0303 effectively controlled southern blight of D. officinale. A total of 1,797 differentially expressed genes were identified by a comparative transcriptome analysis of S. delphinii mycelia treated with MEPF0303 and the untreated control mycelia. Strain MEPF0303 significantly altered the expression of genes related to cell membrane morphological development and integrity, pathogenicity, energy metabolism, and oxidative stress responses. Furthermore, the transcriptome sequencing results were validated by analyzing gene expression via a quantitative real-time polymerase chain reaction. The study results showed that MEPF0303 can inhibit the growth and pathogenicity of S. delphinii, with potential implications for the biological control of southern blight of D. officinale.