Objective To prepare a variety of quality control(QC)materials for SARS-CoV-2 variants as an addition to the conven-tional SARS-CoV-2 nucleic acid QC products for the laboratory detection of mutant strains by optimizing the preparation and purification process of MS2 phage virus-like particle(VLP)technique,and evaluate their performances.Methods The typical mutation sequence fragments or full length S genes were designed and synthesized according to the genomic information of SARS-CoV-2 variants.Then,they were inserted into the downstream of maturase gene,coat protein and the pac-site of MS2 phage to construct a series of recombi-nant expression vectors.After induced by the prokaryotic expression system,the VLP products were purified through the polyethylenei-mine precipitation,ultrafiltration,nuclease digestion,and gel filtration chromatography.The obtained VLP were validated by the nucle-ic acid electrophoresis,protein electrophoresis,protein concentration determination,and fluorescence PCR,and their performances such as nucleic acid residue and stability were also evaluated.Results A total of 10 kinds of VLP containing the targeted sequences of the gene to be tested were prepared.The length of the foreign sequence wrapped in them ranged from 297 bp to 3 822 bp,which could be combined into a variety of QC materials for the mutation detection of different SARS-CoV-2 variants.The prepared VLP QC materials could not be effectively amplified without nucleic acid extraction or reverse transcription steps during the routine nucleic acid detection.The simulated QC samples remained stable after repeated freeze-thaw cycles.They could be stored stably for 2 months at 25 ℃ and 4 weeks at 37 ℃.Conclusion The established preparation and combined purification process of VLP QC materials can encapsulate vari-ous exogenous nucleic acid sequences with different lengths into the viral coat protein to form VLP,with high production efficiency.The VLP QC products prepared by the above process have stable performance and almost no residual exogenous nucleic acid,which can ef-fectively meet clinical requirements and ensure the quality of laboratory testing.

Objective To prepare a variety of quality control(QC)materials for SARS-CoV-2 variants as an addition to the conven-tional SARS-CoV-2 nucleic acid QC products for the laboratory detection of mutant strains by optimizing the preparation and purification process of MS2 phage virus-like particle(VLP)technique,and evaluate their performances.Methods The typical mutation sequence fragments or full length S genes were designed and synthesized according to the genomic information of SARS-CoV-2 variants.Then,they were inserted into the downstream of maturase gene,coat protein and the pac-site of MS2 phage to construct a series of recombi-nant expression vectors.After induced by the prokaryotic expression system,the VLP products were purified through the polyethylenei-mine precipitation,ultrafiltration,nuclease digestion,and gel filtration chromatography.The obtained VLP were validated by the nucle-ic acid electrophoresis,protein electrophoresis,protein concentration determination,and fluorescence PCR,and their performances such as nucleic acid residue and stability were also evaluated.Results A total of 10 kinds of VLP containing the targeted sequences of the gene to be tested were prepared.The length of the foreign sequence wrapped in them ranged from 297 bp to 3 822 bp,which could be combined into a variety of QC materials for the mutation detection of different SARS-CoV-2 variants.The prepared VLP QC materials could not be effectively amplified without nucleic acid extraction or reverse transcription steps during the routine nucleic acid detection.The simulated QC samples remained stable after repeated freeze-thaw cycles.They could be stored stably for 2 months at 25 ℃ and 4 weeks at 37 ℃.Conclusion The established preparation and combined purification process of VLP QC materials can encapsulate vari-ous exogenous nucleic acid sequences with different lengths into the viral coat protein to form VLP,with high production efficiency.The VLP QC products prepared by the above process have stable performance and almost no residual exogenous nucleic acid,which can ef-fectively meet clinical requirements and ensure the quality of laboratory testing.

Spinal surgical site infection (SSI), especially deep SSI after internal fixation is difficult in treatment, with long course of disease and poor prognosis. At present, there are many controversies in the diagnosis and treatment of spinal SSI, with unsatisfactory overall efficacy of its diagnosis and treatment. Besides, no diagnosis and treatment guideline based on evidence-based medicine has been in existence. To this end, the Spinal Infection Group of the Orthopedic Branch of the Chinese Medical Doctor Association and the Spinal Infection Group of the Spinal Surgery Branch of the Chinese Rehabilitation Medicine Association jointly organized relevant experts to formulate Evidence-based clinical guideline for the diagnosis and treatment of surgical site infection in spinal trauma ( version 2024) based on an evidence-based approach. A total of 10 recommendations were proposed on the diagnosis and treatment of spinal SSI, so as to provide a clinical reference for the diagnosis and treatment of spinal SSI.

Objective:To explore the safety and effectiveness of laparoscopic local pancreatectomy in the treatment of cystic neoplasms of pancreatic head.Methods:Retrospective analysis was conducted of data on patients with pancreatic head cystic neoplasms who received laparoscopic surgery at the Department of Hepatobiliary Surgery, the Second Hospital of Hebei Medical University from February 2017 to October 2022. A total of 83 patients were enrolled, including 30 males and 53 females, aged (43.7±16.7) years old. All patients were divided into an observation group ( n=55) and a control group ( n=28) based on different surgical procedures. The observation group underwent laparoscopic local pancreatectomy (laparoscopic duodenum-preserving pancreatic head resection or laparoscopic enucleation), while the control group underwent laparoscopic pancreaticoduodenectomy (LPD). The age, gender, body mass index, postoperative hospital stay, proportion of discharged patients with drainage tubes, surgical time, intraoperative blood loss, intraoperative blood transfusion rate, and fistula were compared between two groups. Results:All patients successfully completed the surgery, and there were no cases of conversion to laparotomy or perioperative deaths. There was no statistically significant difference in age, male proportion, body mass index, postoperative hospital stay, and discharge rate with drainage tube between the two groups of patients (all P>0.05). The observation group had a surgical time of (194.4±114.0) min, intraoperative bleeding of 50 (50, 200) ml, and intraoperative blood transfusion rate of 5.5%(3/55), all of which were better than that of the control group, (380.0±71.6) min, 200 (100, 400) ml, and 32.1%(9/28), with statistical significance (all P<0.05). Among them, the B/C fistula rates in the laparoscopic local pancreatectomy group and LPD group were 12.7%(7/55) and 10.7%(3/28) ( P=0.790), respectively. Conclusion:Compared with traditional LPD, laparoscopic local pancreatectomy can shorten surgical time, reduce intraoperative bleeding, and lower intraoperative blood transfusion rate. And there is no significant disadvantage in the B or C grade fistula.

Spinal surgical site infection (SSI), especially deep SSI after internal fixation is difficult in treatment, with long course of disease and poor prognosis. At present, there are many controversies in the diagnosis and treatment of spinal SSI, with unsatisfactory overall efficacy of its diagnosis and treatment. Besides, no diagnosis and treatment guideline based on evidence-based medicine has been in existence. To this end, the Spinal Infection Group of the Orthopedic Branch of the Chinese Medical Doctor Association and the Spinal Infection Group of the Spinal Surgery Branch of the Chinese Rehabilitation Medicine Association jointly organized relevant experts to formulate Evidence-based clinical guideline for the diagnosis and treatment of surgical site infection in spinal trauma ( version 2024) based on an evidence-based approach. A total of 10 recommendations were proposed on the diagnosis and treatment of spinal SSI, so as to provide a clinical reference for the diagnosis and treatment of spinal SSI.

Objective:To study the clinical characteristics and management strategies of late bleeding after laparoscopic pancreaticoduodenectomy (LPD).Methods:The clinical data of 58 patients with post-pancreaticoduodenectomy hemorrhage (PPH) admitted to the Department of Hepatobiliary Surgery of the Second Hospital of Hebei Medical University from March 2018 to March 2022 were retrospectively analyzed, including 42 males and 16 females, aged (61.88±11.02) years old. According to the occurrence of intra-abdominal erosion factors (e.g., pancreatic fistula, biliary fistula, gastrointestinal anastomotic fistula, intra-abdominal abscess), patients were divided into the erosion group ( n=42) and non-erosion group ( n=16). All patients underwent standard lymphadenectomy. Clinical data including the PPH time-point, occurrence of rebleeding, and treatment outcomes were accessed. The management strategies of PPH in the two groups of patients were analyzed. Results:The PPH time-point in the erosion group and non-erosion patients was 8.00 (5.00, 19.25) d and 21.50 (12.75, 26.75) d, respectively ( P=0.001). PPH can occurred within one month after surgery in both erosion and non-erosion groups. In the erosion group, 31 cases (73.81%, 31/42) were treated by re-operation, two (4.76%, 2/42) by interventional radiology and nine (21.43%, 9/42) with conservative protocol, respectively. In the non-erosion group, five cases (31.25%, 5/16) were treated by re-operation, seven (43.75%, 7/16) by interventional radiology and four (25.00%, 4/16) with conservative protocol, respectively. The incidence of re-bleeding is higher in the erosion group [47.6% (20/42) vs 12.5% (2/16), P<0.05]. Clinical manifestations, sites and severity of bleeding, and treatment outcomes were also different in the erosion and non-erosion groups (all P<0.05). Conclusions:The occurrence of intra-abdominal erosion factors can affect the clinical characteristics and treatment strategy of late bleeding after laparoscopic pancreaticoduodenectomy. Surgery remains the treatment of choice for post-pancreaticoduodenectomy hemorrhage either as an urgent or last resort.

Objective:To evaluate the relationship between regional coronary flow reserve (CFR) obtained from cadmium-zinc-telluride SPECT(CZT SPECT) myocardial functional perfusion imaging (MFPI) and invasive fractional flow reserve (FFR) measured during coronary angiography (CAG) and its clinical value in guiding coronary interventions.Methods:Forty-two patients (30 males, 12 females, age (63.3±9.8) years) who completed CZT SPECT MFPI in the First Affiliated Hospital of Nanjing Medical University from June 2022 to September 2022 and underwent CAG within 3 months were included retrospectively. The concordance of CFR and FFR for diagnosing myocardial ischemia (CFR<2.0 and FFR<0.8) was calculated at the vascular level. The diagnostic efficacy of coronary stenosis≥70% for decreased myocardial blood flow (CFR<2.0) was calculated. Kappa test was used to analyze the data. Results:A total of 126 major coronary arteries were identified in 42 patients, of which 30(23.8%) had a CFR<2.0 by CZT SPECT and 33(26.2%) had stenosis≥70% in CAG. A total of 32 coronary vessels were performed with MFPI CFR and FFR measurements, of which 6 were both decreased and 21 were both normal, so the concordance rate was 84.4%(27/32)( Kappa=0.612, P<0.001). Among 33 coronary vessels with stenosis≥70%, 13 were with CFR≥2.0. Among 30 coronary vessels with CFR<2.0, 10 were with stenosis<70%. When using stenosis≥70% to diagnose CFR decreasing, the sensitivity was 66.7%(20/30), specificity was 86.5%(83/96), positive predictive value was 60.6%(20/33), negative predictive value was 89.2%(83/93), and accuracy was 81.7%(103/126). Conclusions:The concordance between CFR and FFR for the diagnosis of myocardial ischemia is good. Nearly 1/3 of the coronary arteries with decreased CFR have stenosis<70%, whereas nearly 40% of the coronary arteries with stenosis≥70% are not result in myocardial ischemia. Regional CFR determined by CZT SPECT may have potentially significant clinical value in the diagnosis of coronary artery disease and decision-making of coronary intervention.

Objective:To study the retrocolonic approach for laparoscopic pancreaticoduodenec-tomy (LPD).Methods:The clinical data of 53 patients who underwent LPD using the retrocolonic approach at the Second Hospital of Hebei Medical University from January 2019 to December 2021 were analyzed retrospectively. There were 36 males and 17 females, aged (61.9±8.8) years old. The operation time, intraoperative bleeding and postoperative complications were analysed.Results:LPD was successfully performed in 53 patients via the retrocolonic approach. The operation time was (285.7±49.8) min, and the resection time for specimens was (120.0±10.5) min. The median intraoperative blood loss was 200 ml and blood loss ranged from 50 to 800 ml. Among the 53 patients, 3 patients underwent combined portal vein resection and reconstruction (end-to-end anastomosis). The operation time was 300, 325 and 385 min, respectively, and the intraoperative blood loss was 400-800 ml. During the operation, 5 patients (9.43%) had transection of the middle colonic artery and underwent resection of part of the transverse mesocolon due to invasion of the transverse mesocolon by tumours. Postoperative complications occurred in 5 patients (9.43%), including 4 patients with pancreatic fistula and 1 patient with hemorrhage and with delayed gastric emptying. The postoperative passage of first flatus was (5.40±1.14) days in 5 patients with transection and (2.92±1.03) days in 48 patients without transection of the middle colonic artery. All patients were discharged home successfully. The postoperative pathological results showed all patients to achieve R 0 resection. Conclusion:Laparoscopic pancreaticoduodenectomy via the retrocolonic approach was safe and feasible for patients with a large duodenal tumor, pancreatic head uncinate process tumor with or without invasion of the portal vein and mesenteric vessels.

Objective:To study the safety and feasibility of laparosocpic left-liver-first anterior radical modular orthotopic right hemihepatectomy (Lap-Larmorh) in treatment of Bismuth-Corlette type Ⅲa hilar cholangiocarcinoma.Methods:From June 2020 to April 2022, 13 patients with Bismuth-Corlette type Ⅲa hilar cholangiocarcinoma underwent Lap-Larmorh at the Department of Hepatobiliary Surgery of the Second Hospital of Hebei Medical University. There were 8 males and 5 females, aged (60.9±8.4) years. The operation time, intraoperative blood loss, complications and postoperative survival were analyzed.Results:Five patients were treated with percutaneous transhepatic cholangial drainage to reduce jaundice before surgery. All 13 patients successfully underwent the Lap-Larmorh and there was no conversion to laparotomy. The operative time was [ M( Q1, Q3)] 390.0 (355.0, 435.0) minutes, and the intraoperative blood loss was [ M( Q1, Q3)] 800.0 (300.0, 1 100.0) ml. Postoperative complications occurred in 4 patients with pleural effusion, and 1 patient had portal vein thrombosis associated with pleural effusion, who was managed successfully using low molecular weight heparin sodium anticoagulation therapy and pleural effusion tapping. The postoperative hospital stay was (12.5±5.5) days, and there was no perioperative death. Intraoperative frozen pathology showed 12 patients with left hepatic duct with negative margins, and 1 patient with moderate dysplasia. Postoperative paraffin pathology showed 12 patients with bile duct adenocarcinoma, 1 patient with bile duct mucinous adenocarcinoma, 2 patients with tumors of high differentiation, 10 patients with moderate differentiation, and 1 patient with poor differentiative. The R 0 resection rate was 100.0% (13/13) and the tumor diameter was (2.9±0.9) cm. Follow-up by telephone or outpatient clinics after operation showed 1 patients to be lost to follow-up. The 1-year survival rate after operation was 66.7% (8/12). Conclusion:For Bismuth-Corlette type Ⅲa hilar cholangiocarcinoma, the new laparoscopic approach of Lap-Larmorh was safe and feasible.

Multiple plant lineages have independently evolved sex chromosomes and variable kary-otypes to maintain their sessile lifestyles through constant biological innovation.Morus notabilis,a dioecious mulberry species,has the fewest chromosomes among Morus spp.,but the genetic basis of sex determination and karyotype evolution in this species has not been identified.In this study,three high-quality genome assemblies were generated for Morus spp.[including dioecious M.notabilis(male and female)and Morus yunnanensis(female)]with genome sizes of 301-329 Mb and were grouped into six pseudochromosomes.Using a combination of genomic approaches,we found that the putative ancestral karyotype of Morus species was close to 14 protochromosomes,and that sev-eral chromosome fusion events resulted in descending dysploidy(2n=2x=12).We also charac-terized a～6.2-Mb sex-determining region on chromosome 3.Four potential male-specific genes,a partially duplicated DNA helicase gene(named MSDH)and three Ty3_Gypsy long terminal repeat retrotransposons(named MSTG1/2/3),were identified in the Y-linked area and considered to be strong candidate genes for sex determination or differentiation.Population genomic analysis showed that Guangdong accessions in China were genetically similar to Japanese accessions of mul-berry.In addition,genomic areas containing selective sweeps that distinguish domesticated mul-berry from wild populations in terms of flowering and disease resistance were identified.Our study provides an important genetic resource for sex identification research and molecular breeding in mulberry.