Objective To detect and analyze the percentages of CD4+T, CD8+T and invariant na-ture killer T ( iNKT) cells as well as iNKT subsets in different tissues and organs of non-obese diabetic (NOD)/LtJ mice before the onset and in the early and late stages of type 1 diabetes (T1D) for better under-standing the immune function in different disease stages. Methods Female NOD/LtJ mice were selected as experimental subjects. Their fasting blood glucose levels were measured by blood glucose meter. Glycosuria and blood glucose level ≥11. 1 mmol/L in two consecutive detections were used as the diagnostic criteria of T1D. These mice were divided into three groups as follows: non-onset, early stage and late stage groups. Changes in food and water intake, glucose level in the urine, body weight, mental state, fur color and urine volume were recorded. Percentages of CD4+T, CD8+T and iNKT cells and ratios of subsets in peripheral blood, thymus, spleen, liver and inguinal lymph nodes were detected by flow cytometry (FACS). Results (1) Compared with the non-onset and the early stage groups, mice in the late stage group were apathetic and had rough hair. Moreover, significantly increased water and food intake and urine output (P<0. 05) and de-creased body weight, thymus index, spleen index and the absolute lymphocyte counts of spleen, liver and thymus (P<0. 05) were observed in the late stage group. (2) Compared with the non-onset group, the early stage group showed significantly increased percentages of CD4+T cells in spleen, liver, thymus and inguinal lymph nodes (P<0. 05). Compared with the early stage group, the late stage group showed decreased per-centages of CD4+T cells in liver, thymus, inguinal lymph nodes and peripheral blood (P<0. 05). Compared with the non-onset group, the percentages of CD8+T cells in the early stage group were significantly increased in spleen and thymus, but reduced in inguinal lymph nodes (P<0. 05). Compared with the early stage group, the percentages of CD8+T cells in late stage group were significantly reduced in liver and thymus, but increased in inguinal lymph nodes (P<0. 05). (3) The percentages of iNKT cells in liver and inguinal lymph nodes of mice in the early stage group were significantly higher than those of the non-onset group (P<0. 05). The percentages of iNKT cells in peripheral blood and liver of mice in the late stage group were sig-nificantly lower than those of the early stage group (P<0. 05). No significant difference in the percentages of iNKT cells in spleen and thymus was found among the three groups (P>0. 05). (4) Compared with the non-onset group, the percentages of iNKT1 subset in thymus in the early and late stage groups were significantly increased, while the percentages of iNKT2 subset were significantly decreased (P<0. 05). No significant difference in the percentages of iNKT1 and iNKT2 subsets in spleen, liver and inguinal lymph nodes was found among the three groups (P>0. 05). (5) The percentages of iNKT2 subset in spleen, liver and ingui-nal lymph nodes were significantly lower than those of the iNKT1 subset in the three groups (P<0. 05). The percentage of iNKT2 subset in thymus was significantly higher than that of iNKT1 subset in the non-onset group (P<0. 05). (6) Compared with the non-onset and the late stage groups, the early stage group showed significantly increased levels of IFN-γ, IL-4 and IL-17A and up-regulated ratio of IFN-γ/IL-4 (P<0. 05). Compared with the non-onset and the early stage groups, the late stage group showed significantly increased IL-6 level (P<0. 05). Compared with the non-onset group, IL-10 level in the other two groups was in-creased, especially in the late stage group (P<0. 05). No significant difference in IL-2 level was found among the three groups (P>0. 05). Conclusion Increased percentages of iNKT cells and iNKT1 subset in NOD/LtJ mice with early stage of T1D might be involved in the development of T1D.

Objective:To investigate the surgical situations and perioperative outcome of pancreaticoduodenectomy in Jiangsu Province and the influencing factors for postoperative 90-day mortality.Methods:The retrospective case-control study was conducted. The clinicopathological data of 2 886 patients who underwent pancreaticoduodenectomy in 21 large tertiary hospitals of Jiangsu Quality Control Center for Pancreatic Diseases, including The First Affiliated Hospital of Nanjing Medical University, from March 2021 to December 2022 were collected. There were 1 732 males and 1 154 females, aged 65(57,71)years. Under the framework of the Jiangsu Provincial Pancreatic Disease Quality Control Project, the Jiangsu Quality Control Center for Pancreatic Diseases adopted a multi-center registration research method to establish a provincial electronic database for pancrea-ticoduodenectomy. Observation indicators: (1) clinical characteristics; (2) intraoperative and post-operative conditions; (3) influencing factors for 90-day mortality after pancreaticoduodenectomy. Measurement data with skewed distribution were represented as M( Q1, Q3) or M(IQR), and comparison between groups was conducted using the Mann-Whitney U test. Count data were expressed as absolute numbers or constituent ratio, and comparison between groups was conducted using the chi-square test, continuity correction chi-square test and Fisher exact probability. Maximal Youden index method was used to determine the cutoff value of continuous variables. Univariate analysis was performed using the corresponding statistical methods based on data types. Multivariate analysis was performed using the Logistic multiple regression model. Results:(1) Clinical characteristics. Of the 2 886 patients who underwent pancreaticoduodenectomy, there were 1 175 and 1 711 cases in 2021 and 2022, respectively. Of the 21 hospitals, 8 hospitals had an average annual surgical volume of <36 cases for pancreaticoduodenectomy, 10 hospitals had an average annual surgical volume of 36-119 cases, and 3 hospitals had an average annual surgical volume of ≥120 cases. There were 2 584 cases performed pancreaticoduodenectomy in thirteen hospitals with an average annual surgical volume of ≥36 cases, accounting for 89.536%(2 584/2 886)of the total cases. There were 1 357 cases performed pancrea-ticoduodenectomy in three hospitals with an average annual surgical volume of ≥120 cases, accounting for 47.020%(1 357/2 886) of the total cases. (2) Intraoperative and postoperative conditions. Of the 2 886 patients, the surgical approach was open surgery in 2 397 cases, minimally invasive surgery in 488 cases, and it is unknown in 1 case. The pylorus was preserved in 871 cases, not preserved in 1 952 cases, and it is unknown in 63 cases. Combined organ resection was performed in 305 cases (including vascular resection in 209 cases), not combined organ resection in 2 579 cases, and it is unknown in 2 cases. The operation time of 2 885 patients was 290(115)minutes, the volume of intra-operative blood loss of 2 882 patients was 240(250)mL, and the intraoperative blood transfusion rate of 2 880 patients was 27.153%(782/2 880). Of the 2 886 patients, the invasive treatment rate was 11.342%(327/2 883), the unplanned Intensive Care Unit (ICU) treatment rate was 3.087%(89/2 883), the reoperation rate was 1.590%(45/2 830), the duration of postoperative hospital stay was 17(11)days, the hospitalization mortality rate was 0.798%(23/2 882), and the failure rate of rescue data in 2 083 cases with severe complications was 6.529%(19/291). There were 2 477 patients receiving postoperative 90-day follow-up, with the 90-day mortality of 2.705%(67/2477). The total incidence rate of complication in 2 886 patients was 58.997%(1 423/2 412). The incidence rate of severe complication was 13.970%(291/2 083). The comprehensive complication index was 8.7(22.6) in 2 078 patients. (3) Influencing factors for 90-day mortality after pancreaticoduodenectomy. Results of multivariate analysis showed that age ≥ 70 years, postoperative invasive treatment, and unplanned ICU treatment were independent risk factors for 90-day mortality after pancreaticoduodenectomy ( odds ratio=2.403, 2.609, 16.141, 95% confidence interval as 1.281-4.510, 1.298-5.244, 7.119-36.596, P<0.05). Average annual surgical volume ≥36 cases in the hospital was an independent protective factor for 90-day mortality after pancreaticoduodenectomy ( odds ratio=0.368, 95% confidence interval as 0.168-0.808, P<0.05). Conclusions:Pancreaticoduodenectomy in Jiangsu Province is highly con-centrated in some hospitals, with a high incidence of postoperative complications, and the risk of postoperative 90-day mortality is significant higher than that of hospitallization mortality. Age ≥ 70 years, postoperative invasive treatment, and unplanned ICU treatment are independent risk factors for 90-day motality after pancreaticoduodenectomy, and average annual surgical volume ≥36 cases in the hospital is an independent protective factor.