Objective:To explore the association between insulin resistance (IR) and genome-wide DNA methylation based on Shanghai twin study.Methods:Monozygotic twins (MZ) from Shanghai were recruited during 2012-2013, 2017-2018, and 2022-2023. Data were collected by questionnaire survey, physical examination and laboratory tests. Genome-wide DNA methylation was quantified. Generalized linear mixed effect model was applied to analyze the association between methylation level at each site and homeostatic model assessment 2-insulin resistance (HOMA2-IR). Non-paired and paired designs were used to assess the association between DNA methylation and phenotype of IR. Cluster analysis was conducted to identify the clusters of top significant sites. Generalized linear regression was performed to examine the differential methylation patterns from clusters.Results:A total of 100 MZ pairs were included in this study. Hypermethylated cg10535199-2q23.1 ( β=0.74%, P=1.51×10 -7, OR=1.06, 95% CI: 1.03-1.09) and ch.17.49619327- SPOP ( β=0.23%, P=7.54×10 -7, OR=1.17, 95% CI: 1.08-1.28) were identified with suggestive significance. After correcting for multiple testing, no sites reached genome-wide significance. There was no statistical significance in the paired analysis. Two clusters with hypomethylated ( β=-0.39%, P<0.001) and hypermethylated ( β=0.47%, P<0.001) patterns were observed for HOMA2-IR. Conclusions:IR was significantly associated with DNA methylation, and genetic factors might contribute to the association.

【Objective】 To explore the safety and efficacy of a novel endoscopic two-wire guided dilation in the creation of channels in percutaneous nephrolithotomy (PCNL). 【Methods】 Clinical records of 180 patients undergoing PCNL during Oct.2020 and Oct.2022 were retrospectively analyzed. The patients were divided into three groups, 60 in AMD group (fascial amplatz dilation), 60 in OSD group (one shot dilation) and 60 in END group (endoscopic dilation). Time to establish channels, operating time, failure of access, stone clearance rate, drop in hemoglobin, embolization rate, fever rate, blood transfusion rate and postoperative hospitalization were compared among the three groups. 【Results】 There were no significant differences in the general data among the three groups (P>0.05). Compared with AMD and OSD groups, END group needed significantly reduced time to establish the first channel [(5.6±0.8) min vs. (4.9±1.4) min vs. (4.2±0.5) min, (P<0.05)] . Compared with OSD group, END and AMD groups had significantly more hemoglobin drop [(14.0±17.6) g/L vs. (19.4±12.6) g/L vs. (10.2±6.8) g/L, (P<0.05)] . There were no significant differences in terms of failure of establishing channels, operating time, stone clearance rate, embolization rate, fever rate, blood transfusion rate and postoperative hospitality. Four patients needed selective renal artery embolization (1 case in AMD group and 3 in OSD group). No serious complications such as organ injuries, septic shock or death occurred. 【Conclusion】 Endoscopic two-wire guided dilation is simple, with few complications and good application value.