[Objective] To review the clinical information, imaging features, pathological manifestations and prognosis of low-grade oncocytic tumor (LOT), so as to improve the clinical understanding of the disease. [Methods] The imaging, clinicopathological and postoperative follow-up data of 3 LOT cases treated in Peking University Third Hospital during Feb.2020 and Sep.2022 were retrospectively collected. [Results] All patients were male, aged 51—70 years.All tumors were single, with the maximum diameter of 14—21 mm. None of the patients had any specific clinical manifestations.The mass showed a circular isodense shadow on CT.All patients underwent nephron-sparing tumor resection.Postoperative pathology showed that the incision surface of the tumors was brownish-yellow or brown, and the tumors were solid or partially cystic.HE staining showed that the cells were uniformly eosinophilic; the nucleus was round or oval, with slight local perinuclear halo.Immunohistochemistry showed positive CK7 but negative CD117.Genetic testing in case 2 showed 1 potentially clinically significant somatic mutation TSC2.During the follow-up of 12-23 months, no recurrence occurred. [Conclusion] There were no obvious clinical symptoms and imaging features of LOT, which morphologically showed heterozygous or borderline characteristics with renal eosinophilia and renal chromophobe cell carcinoma, and the biological behavior was indolent.Nephron-sparing tumor resection promised good prognosis.

ObjectiveTo observe the effect of Yangxin Tongmai Formula （养心通脉方） by midnight-noon ebb-flow administration method for rat models of premature coronary heart disease （PCHD） with blood stasis syndrome， and to explore the possible mechanism of action from the perspective of DNA methylation differential gene expression. MethodsThere were 3 SD rats in each of the blank group， model group and Yangxin Tongmai Formula group， and the rats in the model group and Yangxin Tongmai Formula group were fed with high-fat chow plus vitamin D3 by gavage plus isoproterenol hydrochloride by subcutaneous injection to construct rat models of PCHD with blood stasis syndrome. After successful modelling， rats in Yangxin Tongmai Formula group were gavaged with 18 g/（kg‧d） of Yangxin Tongmai Formula， and rats in blank group and the model group were gavaged with 4 ml/（kg‧d） of 0.9% NaCl solution， and serum samples of rats in each group were collected for DNA methylation sequencing after 3 weeks to screen for the relevant DNA methylation differentiation genes. In addition， rats with successful modelling of PCHD with blood stasis were randomly divided into model group， Yangxin Tongmai Formula with midnight-noon ebb-flow administration method group ［18 g/（kg‧d） of Yangxin Tongmai Formula was gavaged twice in the heart channel period （12：00） and pericardium channel period （20：00）］， the Yangxin Tongmai Formula control group ［18 g/（kg‧d） of Yangxin Tongmai Formula was gavaged twice at 8：00 and 18：00］ and the Atorvastatin Calcium group ［atorvastatin calcium tablets solution 1.8 mg/（kg‧d） at the same intervention time as that in Yangxin Tongmai Formula control group］， and set up a blank group of 8 rats in each group. The model group and blank group were gavaged with 0.9% NaCl solution 4 ml/（kg‧d） for the same time as the Yangxin Tongmai Formula control group. After 3 weeks of gavage， the blood lipids ［including total cholesterol （TC）， low-density lipoprotein （LDL）， high-density lipoprotein （HDL）］ levels of rats in each group were detected； the HE staining of myocardial tissues and thoracic aorta was used to observe the pathomorphological changes； the levels of serum inflammation indexes ［tumour necrosis factor alpha （TNF-alpha）， lipopolysaccharide （LPS）， and interleukin 10 （IL-10）］ were detected； immunoprecipitation-realtime fluorescence quantitative PCR was used to detect the relative expression of cardiac tissue screening differential genes. ResultsThe genes screened for differentially methylated regions were calmodulin 2 （Calm2）， calcium voltage-gated channel subunit α1s （Cacna1s）， and phospholipase Cβ1 （Plcb1）. Compared with the blank group， rats in the model group showed elevated levels of TC， LDL， TNF-α and LPS， and decreased levels of HDL and IL-10 （P＜0.05 or P＜0.01）； HE staining showed obvious swelling of myocardial fibres， accompanied by a large number of inflammatory cell infiltration， and thickening of the inner wall of the aortic vessels with internal wall damage， which was visible as a large number of lipid cholesterol crystals and obvious inflammatory cell infiltration. Compared with the model group， the TC， LDL， TNF-α and LPS contents of rats in the Yangxin Tongmai Formula with midnight-noon ebb-flow administration method group， the Yangxin Tongmai Formula control group， and the atorvastatin calcium group all reduced， and the contents of HDL and IL-10 all elevated （P＜0.05）， with the improvement of myocardial tissue damage and the reduction of inflammatory infiltration， and the improvement of the damage of the inner lining of the thoracic aorta and the reduction of lipid infiltration. Compared with Yangxin Tongmai Formula control group， LDL， TNF-α and LPS contents reduced， and IL-10 contents increased in the midnight-noon ebb-flow administration method group （P＜0.05）. Compared with the model group， the relative expression of Calm2 and Plcb1 genes decreased and the relative expression of Cacna1s gene increased in Yangxin Tongmai Formula control group and the midnight-noon ebb-flow administration method group （P＜0.05）； compared with the Yangxin Tongmai Formula control group， the relative expression of Calm2 gene decreased and the relative expression of Cacna1s gene increased in the midnight-noon ebb-flow administration method group （P＜0.05）. ConclusionThe intervention of Yangxin Tongmai Formula in the heart channel period （12：00） and pericardium channel period （20：00） was more effective in improving the blood lipid level， inhibiting inflammation， and improving myocardial tissue damage in rats of PCHD with blood stasis syndrome， and Calm2 and Cacna1s genes may be the key targets of Yangxin Tongmai Formula in intervening the blood stasis syndrome of PCHD.