The superiority of magnetic resonance(MR)images in soft tissue imaging makes them indispensable for medical diagnosis and radiotherapy,but factors such as acquisition cost and contraindications limit their widespread application.In contrast,computed tomography(CT)scanning has the advantages of fast imaging speed and low cost.Herein,this review summarizes the research progress of generative deep learning models in the field of medical CT to MR image synthesis,and especially analyzes the technical characteristics,performance advantages,and challenges of various MR image synthesis methods from clinical scenarios such as spinal lesions,acute ischemic stroke,and tumor segmentation.Furthermore,the application value and future research prospects of medical image synthesis are discussed.

The superiority of magnetic resonance(MR)images in soft tissue imaging makes them indispensable for medical diagnosis and radiotherapy,but factors such as acquisition cost and contraindications limit their widespread application.In contrast,computed tomography(CT)scanning has the advantages of fast imaging speed and low cost.Herein,this review summarizes the research progress of generative deep learning models in the field of medical CT to MR image synthesis,and especially analyzes the technical characteristics,performance advantages,and challenges of various MR image synthesis methods from clinical scenarios such as spinal lesions,acute ischemic stroke,and tumor segmentation.Furthermore,the application value and future research prospects of medical image synthesis are discussed.

Pancreatic cancer is also known as the " king of cancer" . It is difficult to diagnose and has a high degree of malignancy. Most patients are in advanced stage when they are found. The prognosis is very poor. Early diagnosis and treatment of pancreatic cancer are very important to improve survival rate and prognosis. In recent years, with the continuous popularization of laparoscopic technology, as well as the updating and iteration of related equipment such as 3D visualization and 4K high-definition laparoscopy, and the continuous maturity of surgical technology, laparoscopic surgery for pancreatic tumors has also made unprecedented progress. This review will discuss the application and development of laparoscopic pancreatic surgery as a treatment strategy for pancreatic cancer based on the existing research progress.

Cancer vaccines represent a promising immunotherapeutic treatment modality. The promotion of cross-presentation of extracellular tumor-associated antigens on the major histocompatibility complex (MHC) class I molecules and dendritic cell maturation at the appropriate time and place is crucial for cancer vaccines to prime cytolytic T cell response with reduced side effects. Current vaccination strategies, however, are not able to achieve the spatiotemporal control of antigen cross-presentation. Here, we report a liposomal vaccine loading the second near-infrared window (NIR-II, 1000-1700 nm) fluorophore BPBBT with an efficient photothermal conversion effect that offers an NIR-light-triggered endolysosomal escape under the imaging guidance. The NIR-II image-guided vaccination strategy specifically controls the cytosolic delivery of antigens for cross-presentation in the draining lymph nodes (DLNs). Moreover, the photothermally induced endolysosomal rupture initiates autophagy. We also find that the adjuvant simvastatin acts as an autophagy activator through inhibiting the PI3K/AKT/mTOR pathway. The light-induced autophagy in the DLNs together with simvastatin treatment cooperatively increase MHC class II expression by activating autophagy machinery for dendritic cell maturation. This study presents a paradigm of NIR-II image-guided light-triggered vaccination. The approach for remote control of antigen cross-presentation and autophagy represents a new strategy for vaccine development.

OBJECTIVE To prepare Leonurine hydrochloride tablets and evaluate the quality. METHODS The wet granulation technology was adopted ；leonurine hydrochloride was used as the crude drug ，and the types of fillers ，disintegrants，binders and lubricants were screened by single-factor experiments. Combined with orthogonal experiments ，using the cumulative dissolution rate within 15 minutes（using water as dissolution media ）as index ，the proportion of disintegrants ，the mass fraction of binder solution，and the proportion of lubricants were screened and verified. The in vitro dissolution behavior of the prepared Leonurine hydrochloride tablets （dissolution media were hydrochloric acid solution of pH 1.2，acetic acid-sodium acetate solution of pH 4.5， phosphate buffer solution of pH 6.8，water），tablet appearance ，hardness，friability and content uniformity were tested according to the general principles in 2020 edition of Chinese Pharmacopoeia （part Ⅳ）. RESULTS The optimal formulation of Leonurine hydrochloride tablets included leonurine hydrochloride crude drug of 500 mg，dextrin of 9 250 mg，crosslinking polyving y- pyrrolidone of 200 mg，magnesium stearate of 50 mg，1％ hydroxypropyl methyl cellulose solution of 4 mL. The average 15-minute cumulative dissolution rate of the three batches of tablets was 81.25％（RSD＝1.12％，n＝3）. In above 4 dissolution media，the dissolution equilibrium of prepared tablets could be reached within 30 minutes，and the cumulative dissolution rates exceeded 85％. The prepared tablets had uniform beige in color ，smooth surface ，complete edge ，no mottle ，spot，foreign matter ， etc.，hardness of 57.3 N（n＝6），weight loss rate of 0.15％. The content uniformity was in accordance with relevant provisions in 2020 edition of Chinese Pharmacopoeia （part Ⅳ）. CONCLUSIONS Leonurine hydrochloride tablets are successfully prepared ， and the quality comply with relevant regulations.

Objective:To study the safety and efficacy of laparoscopic subtotal distal pancreatectomy using the arterial first approach in treatment of patients with pancreatic neck-body cancer after neoadjuvant chemotherapy.Methods:The clinical data of patients who underwent laparoscopic subtotal distal pancreatectomy after neoadjuvant chemotherapy at the Department of Pancreatic Surgery, Hunan Provincial People's Hospital from January 2019 to June 2021 were analyzed retrospectively. Seven patients were included in this study. There were 3 males and 4 females, aged 55(46, 67) years old. The clinical data analysed included chemotherapy, preoperative, intraoperative, postoperative and follow-up data. Follow up was done by outpatient visits, or contact using wechat or telephone.Results:Five borderline staged patients were treated with the AG chemotherapy regimen (gemcitabine+ albumin-bound paclitaxel), and two patients with locally advanced stage were treated with the mFOLFIRINOX chemotherapy regimen (oxaliplatin+ irinotecan+ calcium folate+ fluorouracil). All the 7 patients underwent portal vein/superior mesenteric vein resection and reconstruction using the superior mesenteric artery priority approach. The operation time was 400(350, 440) min, and the intraoperative blood loss was 300(150, 400) ml. Postoperative complications occurred in 2 patients with grade B pancreatic fistula and refractory ascites in 1 patient each. The postoperative hospital stay was 11(10, 14) days. All 7 patients underwent R 0 resection. During a follow-up period of 9 to 33 months, 5 patients were still alive without tumor, 1 patient survived with tumor, and 1 patient had died of recurrence. Conclusion:In selected cases, laparoscopic subtotal distal pancreatectomy for pancreatic neck-body cancer after neoadjuvant chemotherapy was safe and feasible.

Objective:To study the value of metastatic positivety in lymph nodes group 8a in deciding on extended lymph node dissection in pancreaticoduodenectomy(PD) for pancreatic head cancer.Methods:A retrospective study on 165 patients with pancreatic head cancer treated with PD at the Department of Pancreas and Spleen Surgery, Hepatobiliary Hospital of Hunan Provincial People's Hospital between January 2014 to June 2019 was performed. There were 101 males and 64 females with ages ranging from 38 to 75 (median 57) years. Patients who underwent standard lymph node dissection were included in the standard group ( n=88), and extended lymph node dissection in the extended group ( n=77). These patients were further divided into 4 subgroup. Subgroup A (standard PD in patients with negative nodes in group 8a, n=61), Subgroup B (extended PD in patients with negative nodes in group 8a, n=47), Subgroup C (standard PD in patients with positive nodes in group 8a, n=27), and Subgroup D (extended PD in patients with positive nodes in group 8a, n=30). The operation time, intraoperative blood loss, postoperative survival rates, complications were compared among the groups and subgroups. Results:The operation time and intraoperative blood loss of the standard group were (456.8±30.4) min and (264.28±101.14) ml, respectively, which were significantly lower than the extended group of (507.1±45.7) min and (388.9±155.3) ml (all P<0.05). The incidence of postoperative complications in the extended group (31.2%, 24/77) was significantly higher than that in the standard group (14.8%, 13/88) ( P<0.05). When compared with subgroup B, the cumulative survival rate of patients in subgroup A was not significantly different ( P>0.05). However, the cumulative survival rate of patients in subgroup C was significantly lower than that in subgroup D ( P<0.05). The cumulative survival rate of subgroup A was also significantly better than that of subgroup C ( P<0.05). There was no significant difference in the cumulative survival rates between group B and group D ( P>0.05). Conclusions:PD with extended lymph node dissection improved the survival rates in patients with cancer of the head of the pancreas with positive lymph nodes in group 8a. For these patients, extended lymph node dissection is recommended. With negative lymph nodes in group 8a, standard lymph node dissection is recommended.

Objective:To study the indications and clinical efficacy of video assisted small incision in treatment of infected pancreatic necrosis.Methods:A retrospective study was conducted on 27 patients with infected pancreatic necrosis treated by video assisted small incision at the Department of Pancreatic and Splenic Surgery, Hunan Provincial People's Hospital, from January 2018 to December 2019. The surgical approach, operation time, intraoperative blood loss, postoperative hospital stay and complications were analysed. Postoperative follow-up was carried out at outpatients’ clinic, and the patient's time to full recovery and long-term complications were studied.Results:The 27 patients successfully underwent the operations. There were 22 males and 5 females, aged (50.6±6.2) years. The treatment results were analyzed according to the different surgical approaches: the retroperitoneal approach group ( n=4); the omental sac approach group (n=14); the intercostal space approach group ( n=2); and the combined approach group ( n=7). The operation time was (85.3±31.6)min. The intraoperative blood loss was 65.0(45.2, 121.4)ml. The postoperative hospital stay was 23.0(12.5, 36.1)days. The incidence of complications (Clavien-Dindo grade Ⅲ and above) was 14.8%(4/27). There were 2 patients in this study who were admitted to the intensive care unit due to postoperative hemorrhage: 1 patient responded well to conservative treatment and the remaining patient required interventional treatment. Another patient because of poor results, underwent debridement by laparotomy 2 weeks after the operation. There was 1 patient who developed grade C pancreatic fistula which was cured by surgical treatment 6 months later. On follow-up, 2 patients developed colonic fistula 2 weeks after surgery and 2 patients gastric fistula 1 week and 3 weeks after surgery. These patients responded to conservative treatment. Conclusion:With proper case selection, video assisted small incision could safely and effectively be used to treat infected pancreatic necrosis.

Objective:To investigate the clinical efficacy of perihilar surgical techniques for diffuse hepatolithiasis.Methods:The retrospective and descriptive study was conducted. The clinicopathological data of 122 patients with diffuse hepatolithiasis who were admitted to Hunan Provincial People's Hospital from January 2010 to December 2015 were collected. There were 39 males and 83 females, aged from 21 to 82 years, with a median age of 51 years. After perihilar hepatectomy, the first, second and third divisions of hepatic ducts were opened longitudinally. Strictures in the bile ducts were relieved by stricturoplasty and internal bile duct anastomosis, and stones were removed by multiple methods under direct vision. After resection of severe atrophic liver segment along the plane of hepatic atrophy or bile duct stricture, T-tube or hepaticojejunos-tomy was used for internal drainage. Observation indicators: (1) surgical situations; (2) stricture relief and stone removal. (3) Follow-up. Follow-up was conducted by Wechat, telephone interview or outpatient examination. Patients were followed up once every 3 months in the postoperative 1 year through liver function and abdominal B-ultrasound examination. Subsequently, liver function and abdominal B-ultrasound were reexamined once a year. Magnetic resonance cholangiopancreato-graphy and computed tomography were performed when cholangitis or stone recurrence was suspected to analyze stone recurrence and patient survival. The follow-up was up to July 2020. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M(range). Count data were expressed as absolute numbers or percentages. Results:(1) Surgical situations: for the 122 patients, the operation time, hepatic portal occlusion time, volume of intraoperative blood loss, duration of postoperative hospital stay were (253±71)minutes, 15 minutes(range, 14?38 minutes), 200 mL(range, 100?1 100 mL), (12±5)days. Postoperative complications occurred to 40 of 122 patients. There were 9 cases of incision infection, 8 cases of bile leakage (5 cases of bile leakage at hepatic section, 3 cases of choledochojejunostomy leakage), 8 cases of septicemia, 7 cases of pleural effusion, 5 cases of abdominal abscess, 3 cases of liver failure, 1 case of biliary bleeding. Some patients had multiple complications. Among the 122 patients, 2 cases died after operation, including 1 case of postoperative liver failure and 1 case of disseminated intravascular coagulation caused by biliary-intestinal anastomotic leakage complicated with sepsis. Patients with bile leakage and abdominal abscess were improved after puncture and drainage under the guidance of B-ultrasound. Patients with cholangiojejunal anastomotic bleeding were embolized through the right hepatic artery. The other complications were improved after conservative treatment. (2) Stricture relief and stone removal: 85 of 88 patients with biliary stricture were relieved, with the stricture relief rate of 96.59%(85/88). Among the 122 patients, 103 cases had stones completely removed and 19 cases had residual stones. The immediate stone clearance rate was 84.43%(103/122). Of the 19 patients with residual stones, choledochoscopy was refused in 3 cases and choledochoscope lithotripsy was performed in 16 cases, of which 7 cases were removed and 9 cases were still residual stones. Of the 122 patients, 110 cases were finally removed stones, 12 cases were eventually residual stones, and the final stone clearance rate was 90.16%(110/122). (3) Follow-up: among the 122 patients, 120 cases including 110 cases with find stone removal and 10 cases with residual stones were followed up for (78±14)months. The 1-, 3, 5-year stone recurrence rates of 120 patients were 0.83%(1/120), 6.67%(8/120), 9.17%(11/120), respectively. The 1-, 3-, 5-year stone recurrence rates of 110 patients with final stone removal were 0, 5.45%(6/110), 5.45%(6/110), respectively. The number of cases with stone recurrence at postoperative 1-, 3- and 5-year of 10 patients with residual stones were 1, 2, 5 cases, respectively. Of 120 patients with follow-up, 1 case died of end-stage liver disease, and the other patients had good survival.Conclusion:Perihilar surgical techniques for diffuse hepatolithiasis is safe and effective.

Objective:To study and analyse the results of postoperative hemorrhage after laparoscopic pancreaticoduodenectomy (LPD).Methods:The clinical data of patients who underwent LPD from May 2011 to December 2019 at Hunan Provincial People's Hospital were retrospectively analyzed. The clinical characteristics of patients, onset time of postoperative hemorrhage, location of postoperative hemorrhage, postoperative biliary fistula, pancreatic fistula, infection and other short-term complications, reoperation and mortality rates were analyzed.Results:Of 356 patients who underwent LPD in this study, there were 200 males and 156 females, aged (58.0±10.5) years. The postoperative complication rate was 33.1% (118/356), the reoperation rate was 6.5% (23/356), and the mortality rate was 2.5% (9/356). The most common complications were postoperative hemorrhage [15.2% (54/356)], pancreatic fistula [14.6%(52/356)] and abdominal infection [13.8%(49/356)]. The onset time of postoperative hemorrhage was usually in the 1st - 14th day, and the highest rate of postoperative hemorrhage was 3.9% (14/356) on the first day after surgery. The postoperative hemorrhage rate then showed a downward trend, but increased again on the 7th day. The extraluminal hemorrhage locations were relatively widely distributed, and the incidence of gastrointestinal anastomotic hemorrhage in patients with intraluminal hemorrhage was the highest [67.9%(19/28)]. Of the 9 patients who died, 7 were related to postoperative bleeding.Conclusions:LPD resulted in a high incidence of complications. Postoperative hemorrhage was a complication that had the greatest impact on short-term recovery of patients. It was also an important cause of reoperation and death. In addition to postoperative bleeding caused by pancreatic fistula, gastrointestinal anastomotic bleeding was also clinically important.