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951.
Qiang Fu Le Xu Yiwei Wang Qi Jiang Zheng Liu Junyu Zhang Quan Zhou Han Zeng Shanyou Tong Tao Wang Yangyang Qi Baoying Hu Hangcheng Fu Huyang Xie Lin Zhou Yuan Chang Yu Zhu Bo Dai Jiejie Xu 《European urology》2019,75(5):752-763
Background
Glutamine addiction is a hallmark of clear cell renal cell carcinoma (ccRCC); yet whether glutamine metabolism impacts local immune surveillance is unclear. This knowledge may yield novel immunotherapeutic opportunities.Objective
To seek a potential therapeutic target in glutamine-addicted ccRCC.Design, setting, and participants
Tumors from ccRCC patients from a Shanghai cohort and ccRCC tumor data from The Cancer Genome Atlas (TCGA) cohort were analyzed. In vivo and in vitro studies were conducted with fresh human ccRCC tumors and murine tumor cells.Outcome measurements and statistical analysis
Immune cell numbers and functions were analyzed by flow cytometry. Glutamine and cytokine concentrations were determined. Survival was compared between different subpopulations of patients using Kaplan-Meier and Cox regression analyses.Results and limitations
We found that in ccRCC, high interleukin (IL)-23 expression was significantly associated with poor survival in both TCGA (overall survival [OS] hazard ratio [HR] = 2.04, cancer-specific survival [CSS] HR = 2.95; all p < 0.001) and Shanghai (OS HR = 2.07, CSS HR = 3.92; all p < 0.001) cohorts. IL-23 blockade prolongs the survival of tumor-bearing mice, promotes T-cell cytotoxicity in in vitro cultures of human ccRCC tumors, and augments the therapeutic benefits of anti-PD-1 antibodies. Mechanistically, glutamine consumption by ccRCC tumor cells results in the local deprivation of extracellular glutamine, which induces IL-23 secretion by tumor-infiltrating macrophages via the activation of hypoxia-inducible factor 1α (HIF1α). IL-23 activates regulatory T-cell proliferation and promotes IL-10 and transforming growth factor β expression, thereby suppressing tumor cell killing by cytotoxic lymphocytes. The positive correlations between glutamine metabolism, IL-23 levels, and Treg responses are confirmed in both TCGA cohort and tumors from Shanghai ccRCC patients. Study limitations include the unclear impacts of glutamine deprivation and IL-23 on other immune cells.Conclusions
Macrophage-secreted IL-23 enhanced Treg functions in glutamine-addicted tumors; thus, IL-23 is a promising target for immunotherapy in ccRCC.Patient summary
In this study, we analyzed the immune components in glutamine-addicted clear cell renal cell carcinoma (ccRCC) tumors from two patient cohorts and conducted both in vitro and in vivo studies. We found that ccRCC tumor cell-intrinsic glutamine metabolism orchestrates immune evasion via interleukin (IL)-23, and IL-23–high patients had significantly poorer survival than IL-23–low patients. IL-23 should thus be considered a therapeutic target in ccRCC, either alone or in combination with immune checkpoint inhibitors. 相似文献952.
Zhang Di Tang Xiaojing Gao Yuan Yu Hongjing Wen Bin Fu Lili Song Shuwei Mei Changlin 《中华肾脏病杂志》2019,35(4):288-294
Objective To screen Oxalobacter formigenes (OxF) from fresh feces of healthy adults, and study its effect on the the prevention of calcium oxalate kidney stones. Methods OxF was screened and cultured from fresh feces of healthy adults. The rat model of calcium oxalate stone was established by esophageal gavage of 0.8% of ethylene glycol. Rats were divided into a control group and four groups of rats with ethylene glycol-induced calcium oxalate kidney stones according to random number table. Three groups were treated with 106 CFU, 107 CFU, 108 CFU viable OxF every day, respectively, for 4 weeks. The blood and 24-hour urine samples were collected to detect the serum creatinine, urea nitrogen, serum and urine calcium, phosphorus, magnesium and urine oxalate every week. At the end of the 4th week, the rats were sacrificed and the kidney tissues were stained with HE and Yasue. The deposition and content of calcium oxalate crystals were observed under a light microscope. Results The bacteria strain isolated from fresh feces of healthy adults was 100% as same as the known ATCC35274 bacteria strain, which means the strain screened is OxF. Among the 5 groups, there were no significant differences in body weight, Scr, BUN, serum calcium, blood magnesium, blood phosphorus, urinary magnesium and urinary phosphorus. The 24-hour urinary calcium excretion in the model group was significantly lower than that of the control group (P<0.05). After intervention with OxF solution, the 24-hour urinary calcium excretion in the 108 CFU OxF group was significantly higher than that in the model group (P<0.05), while there was no significant difference between the other intervention groups and the model. The oxalic acid excretion of 106 CFU OxF group and 107 CFU OxF group was lower than that of the model, but the difference did not reach statistical significance (P>0.05). The 24 h oxalic acid excretion in the 108 CFU OxF group was significantly lower than that of the model at the end of first week (P<0.05), and continued to decrease for the next 3 weeks. After 4 weeks of intervention, no crystal formation was observed in the control group under the deflection microscope, but a large amount of calcium oxalate crystals were formed in the renal cortex and renal medulla. The crystals were piled up and connected to each other. Yasue staining coincided with the calcium oxalate crystal in the same part of the kidneys. Compared with the model, there was no significant change in the score of calcium oxalate crystal in the kidneys of 106 CFU OxF group and 107 CFU OxF group, while the score of calcium oxalate crystal in the kidneys of 108 CFU OxF group was significantly lower (P<0.05). Conclusions OxF are successively screened from healthy adults. Daily administration of 108 CFU OxF can safely and effectively reduce the urinary oxalic acid excretion, prevent the formation of calcium oxalate crystals and inhibit the formation of stones in kidneys of rats. 相似文献
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目前新型冠状病毒肺炎疫情防控形势严峻,各级医疗机构在做好新型冠状病毒肺炎防控的同时,还需提供优质安全的常规医疗服务。笔者旨在通过严格患者分类管理以及围术期标准预防,为需行外科治疗的患者,尤其是需行急诊外科治疗的患者提供优质安全的医疗服务,减少院内感染,为新型冠状病毒肺炎防控贡献一份力量。 相似文献
959.
This paper is concerned with the classical problem of wave propagation in
discrete models of nonuniform resolution. We extend the traditional asynchronous
variational integrators (AVIs) method to higher order and couple different spatial elements to adapt to nonuniform meshes. We show that the extension of AVIs method
is stable, convergent and may reduce the spurious inter-grid reflection across meshes
with different sizes. Numerical experiments are provided to verify the stability and
convergence of the extended AVIs. The total energy is numerically conserved in our
experiments. 相似文献
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