BACKGROUND:Fracture healing is a very complex physiological process,which is influenced by many factors.In recent years,the use of biomechanical factors in fracture healing has been a major focus in the field of orthopedics,and the mechanical stress environment around the fracture end has an important role in regulating fracture healing.Among them,the study of the mechanism of compressive mechanics on the cytokines of fracture ends is a hot spot for bone-related researchers.OBJECTIVE:To summarize the current status and recent advances in the study of the mechanism of action of compressive stress on cytokines in fracture healing in recent years.METHODS:A search with the keywords of"compressive stress,fracture healing,cytokine,bone morphogenetic protein,fibroblast growth factor,platelet-derived growth factor,vascular endothelial growth factor,interleukin,tumor necrosis factor-α"in Chinese and English was conducted in the CNKI,WanFang,PubMed,and Web of Science.Initially 506 articles were retrieved,and 94 eligible articles that met the criteria were screened and finally summarized.RESULTS AND CONCLUSION:Current studies have found that compressive stress has different effects on different cytokines during fracture healing,which can be achieved mainly by influencing cell signaling,gene expression regulation,and modulation of cell behavior.Among them,compressive stress can be linked to cytokines such as bone morphogenetic protein,fibroblast growth factor,platelet-derived growth factor,vascular endothelial growth factor,interleukin,and tumor necrosis factor-α.This process involves cell proliferation,differentiation and migration,inflammatory response,and changes in the environmental and nutritional conditions of the fracture end,which are key factors affecting fracture healing.The whole paper summarizes the complexity of cytokine action mechanism,the mechanism of compressive stress on its regulation needs to be further carried out in-depth research,and the problems and limitations in the research are considered and future prospects.

Objective To explore the impact of number of positive regional lymph nodes (nPRLN) in N1 stage on the prognosis of non-small cell lung cancer (NSCLC) patients. Methods Patients with TxN1M0 stage NSCLC who underwent lobectomy and mediastinal lymph node dissection from 2010 to 2015 were screened from SEER database (17 Regs, 2022nov sub). The optimal cutoff value of nPRLN was determined using X-tile software, and patients were divided into 2 groups according to the cutoff value: a nPRLN≤optimal cutoff group and a nPRLN>optimal cutoff group. The influence of confounding factors was minimized by propensity score matching (PSM) at a ratio of 1 : 1. Kaplan-Meier curves and Cox proportional hazards models were used to evaluate overall survival (OS) and lung cancer-specific survival (LCSS) of patients. Results A total of 1316 patients with TxN1M0 stage NSCLC were included, including 662 males and 654 females, with a median age of 67 (60, 73) years. The optimal cutoff value of nPRLN was 3, with 1165 patients in the nPRLN≤3 group and 151 patients in the nPRLN>3 group. After PSM, there were 138 patients in each group. Regardless of before or after PSM, OS and LCSS of patients in the nPRLN≤3 group were superior to those in the nPRLN>3 group (P<0.001). N1 stage nPRLN>3 was an independent prognostic risk factor for OS [HR=1.52, 95%CI (1.22, 1.89), P<0.001] and LCSS [HR=1.72, 95%CI (1.36, 2.18), P<0.001]. Conclusion N1 stage nPRLN>3 is an independent prognostic risk factor for NSCLC patients in TxN1M0 stage, which may provide new evidence for future revision of TNM staging N1 stage subclassification.

BACKGROUND:Fracture healing is a very complex physiological process,which is influenced by many factors.In recent years,the use of biomechanical factors in fracture healing has been a major focus in the field of orthopedics,and the mechanical stress environment around the fracture end has an important role in regulating fracture healing.Among them,the study of the mechanism of compressive mechanics on the cytokines of fracture ends is a hot spot for bone-related researchers.OBJECTIVE:To summarize the current status and recent advances in the study of the mechanism of action of compressive stress on cytokines in fracture healing in recent years.METHODS:A search with the keywords of"compressive stress,fracture healing,cytokine,bone morphogenetic protein,fibroblast growth factor,platelet-derived growth factor,vascular endothelial growth factor,interleukin,tumor necrosis factor-α"in Chinese and English was conducted in the CNKI,WanFang,PubMed,and Web of Science.Initially 506 articles were retrieved,and 94 eligible articles that met the criteria were screened and finally summarized.RESULTS AND CONCLUSION:Current studies have found that compressive stress has different effects on different cytokines during fracture healing,which can be achieved mainly by influencing cell signaling,gene expression regulation,and modulation of cell behavior.Among them,compressive stress can be linked to cytokines such as bone morphogenetic protein,fibroblast growth factor,platelet-derived growth factor,vascular endothelial growth factor,interleukin,and tumor necrosis factor-α.This process involves cell proliferation,differentiation and migration,inflammatory response,and changes in the environmental and nutritional conditions of the fracture end,which are key factors affecting fracture healing.The whole paper summarizes the complexity of cytokine action mechanism,the mechanism of compressive stress on its regulation needs to be further carried out in-depth research,and the problems and limitations in the research are considered and future prospects.

The 20th National Congress of the Communist Party of China emphasized the expansion of international scientific and technological exchanges and cooperation. Against this backdrop, the radiological health research institutions bear important responsibilities in the field of international radiological health. As a key institution in the industry, the National Institute for Radiological Protection (NIRP), Chinese Center for Disease Control and Prevention shoulders the important mission of promoting international exchanges in radiation health in China. A case study was conducted on the NIRP using data of official overseas visits from 2010 to 2024. The SWOT analysis was used to comprehensively and systematically examine the strengths, weaknesses, opportunities, and challenges of NIRP in international cooperation and exchanges. To effectively enhance the depth and scope of international exchanges, this article proposes a series of innovative optimization strategies such as establishing dedicated personnel positions to ensure efficient handling of affairs, implementing stringent approval procedures to guarantee the rationality and compliance of overseas visits, strengthening pre-departure training to improve the professionalism of outbound personnel, conducting follow-up evaluations to continuously refine management practices, and centralizing the management of official passports to ensure their secure use. This article aims to provide practical optimization strategies for the management of official overseas visits for NIRP and other similar institutions, promote international exchanges and cooperation in the field of radiation health, and help China play a more important role in the global radiation health field.

BACKGROUND:Adult stem cell therapy is one of the research hotspots in the field of peripheral nerve injury repair and regeneration.With excellent properties of mesenchymal stem cells such as high acquisition rate,wide source,and rapid proliferation,mesoderm have been regarded as the ideal source of adult stem cells,while ectoderm-derived adult stem cells,especially neural crest stem cells,have certain neurogenic properties and attract more and more attention from researchers. OBJECTIVE:To mainly review the role and mechanism of multifunctional adult stem cells from ectoderm and mesoderm in peripheral nerve injury repair and regeneration,so as to explore the research progress and application prospect of adult stem cells from different sources and discuss the potential application value of adult stem cell therapy and the problems to be solved in connection with clinical studies. METHODS:The first author searched the relevant articles published from December 2001 to February 2024 in PubMed and SinoMed by computer in February 2024.The Chinese and English search terms were"ectodermal stem cells,mesenchymal stem cells,peripheral nerve injury,repair,regeneration."Finally,69 articles were included and analyzed. RESULTS AND CONCLUSION:(1)Ectodermal adult stem cells have excellent differentiation and regeneration potential,especially epidermal neural crest stems cells,olfactory stem cells,and dental ectomesenchymal stem cells,which have certain neurogenic properties and can express neural specific markers in vitro.However,relevant clinical research needs to be accumulated.(2)There are many types of adult stem cells derived from mesoderm,which are easy to obtain and purify.Among them,the efficacy and safety of bone marrow mesenchymal stem cells and umbilical cord mesenchymal stem cells in the repair of peripheral nerve injury are supported by clinical trials;that is,they can improve sensory and motor nerve conduction and there are no complications and obvious adverse reactions in follow-up.The acquisition of bone marrow mesenchymal stem cells needs invasive surgery and requires the patient to match the donor bone marrow type,which limit the application to some extent.Although umbilical cord mesenchymal stem cells do not require invasive harvesting,their isolation is difficult and phenotypically unstable.(3)Adult stem cells derived from endoderm often fail to grow in vitro,so the possibility of clinical application is low.(4)In conclusion,bone marrow mesenchymal stem cells are still the first choice for adult stem cell therapy in the treatment of peripheral nerve injury,which is suitable for cases without surgical contraindications and meeting the matching requirements,followed by umbilical cord mesenchymal stem cells supplemented by improved isolation methods and advanced phenotypic stability strategies.(5)Dental ectomesenchymal stem cells and adipose-derived mesenchymal stem cells have high application potential and need to be further tested in clinical trials.Other adult stem cells derived from ectodermal and mesodermal layers have significant advantages in animal and cell experimental studies due to their excellent properties.

Objective:To assess the safety of a novel domestically developed direct visualization system of peroral cholangiopancreatoscopy for the exploration of biliary tract.Methods:Clinical data from 384 patients with biliary tract diseases who underwent endoscopic retrograde cholangiopancreatography (ERCP) at the Endoscopy Center of Shanghai Xuhui District Central Hospital from November 2017 to December 2022 were retrospectively analyzed. Patients were categorized into 2 groups based on the type of cholangioscope: the novel cholangiopancreatoscopy system group ( n=159) and the SpyGlass group ( n=225). In the novel cholangiopancreatoscopy system group, the new direct visualization system of China-made peroral cholangiopancreatoscopy was used for bile duct exploration, while the SpyGlass group utilized the SpyGlass system for bile duct inspection. Propensity score matching (PSM) was used as a nearest-neighbor method with a caliper of 0.01 to minimize confounding factors, resulting in a balanced sample of 122 patients in each group after matching. The primary outcome was the incidence of short-term complications, with secondary outcomes including technical success rates and post-treatment outcomes. Results:After PSM, there were no significant differences in baseline characteristics between the two groups ( P>0.05). Regarding short-term postoperative complications, pancreatitis occurred in 1.6% (2/122) of patients in the novel cholangiopancreatoscopy system group and 7.4% (9/122) in the SpyGlass group. The new system significantly reduced the incidence of post-procedure pancreatitis ( χ2=4.665, P=0.031). The cholecystitis was absent in the novel cholangiopancreatoscopy system group, while it occurred in 0.8% (1/122) cases in the SpyGlass group, with no significant difference between the two groups after the procedure ( P=1.000). Regarding technical success rate, the novel system group achieved a rate of 99.2% (121/122), while the SpyGlass group achieved 97.5% (119/122) ( P=0.622). A slightly higher success rate was observed in the novel system group.There were 81 cases of postoperative biliary drainage in the novel cholangiopancreatoscopy system group and 74 cases in the SpyGlass group. Conclusion:The novel direct visualization system of peroral cholangiopancreatoscopy is safer than SpyGlass in the exploration of biliary system diseases. Endoscopists are encouraged to choose the appropriate cholangioscopy system based on individual patient characteristics for the direct visualization, diagnosis, and treatment of biliary diseases.

Objective:To analyze the short-term hospital-based transmission characteristics and gene variation of Carbapenem-Resistant Klebsiella pneumoniae (CRKP) by genome-wide technique to provide evidence for transmission control. Methods:The experimental strain was derived from all the CRKP isolated in Affiliated Hospital of North China University of Science and Technology from October 2022 to December 2023. Strain identification and drug susceptibility were tested with VITEK 2-Compact automatic bacterial identification drug susceptibility analyzer or disk method, and the results were interpreted through whole genome sequencing. The ST type, carbapenem resistance gene, virulence factor, and O serotype of the collected strains were analyzed.Results:Among the 115 strains of CRKP, 94 strains were isolated from the intensive care unit (ICU), accounting for 81.7%, and 21 strains were isolated from the non-intensive care unit (NICU), accounting for 18.3%. The 115 strains of CRKP can be divided into 11 ST types, of which ST11 type was the most (54.8%, 63/115), followed by ST15 type (22.6%, 26/115) and ST5492 type (15.7%, 18/115). Type ST5492 was a new clonal group in the region. The 115 strains of CRKP could be divided into 7 O serotypes, most of which were O2a type(32.2%,37/115), followed by O5 type(30.4%,35/115) and O1 type(27.8%,32/115). The resistance genes of carbapenem antibiotics showed that there were 107 strains carrying the blaKPC-2 gene, one strain with the blaNDM-1 gene, and one strain with both the blaKPC-2 and blaNDM-13 genes. Virulence genes were detected in 55 CRKP strains (47.8%, 55/115), among which six strains detected peg-344, iucA, iroB, rmpA, and rmpA2 virulence genes (5.2%, 6/115). Four virulence genes ( peg-344, iucA, rmpA, and rmpA2) were detected in 34 strains (29.6%, 34/115). Three virulence genes ( iucA, iroB and rmpA) were detected in two strains (1.7%, 2/115). Three virulence genes ( peg-344, iucA and rmpA) were detected in one strain (0.8%, 1/115). IucA and rmpA virulence genes were detected in 12 strains (10.4%, 12/115). KPC-2_ST11_O2a, KPC-2_ST15_O1 and KPC-2_ST5492_O5 were dominant clones, and their distribution was mainly in the intensive care unit. The whole genome sequence analysis showed that there were three dominant clones, among which ST11 clones were subdivided into three dominant O serotypes, all of which were mainly in the intensive care unit. Conclusion:The popular strain in the hospital of CRKP is a KPC-2_ST11 clone group carrying iucA, rmpA/rmpA2, with cross-department transmission and mutation. ST5492 is a newly-launched clone type. The intensive care unit of hvKP carrying five virulence genes, including peg-344, should be alert to the epidemic risk of CR-hvKP outbreak.

Postmenopausal osteoporosis (PMOP), a bone metabolic imbalance disorder induced by estrogen deficiency, necessitates novel prevention and treatment strategies that transcend the constraints of conventional therapeutic approaches. Melatonin, a signaling molecule secreted by the pineal gland, plays a key role in maintaining circadian rhythms and regulating bone metabolism. In recent years, numerous studies both domestically and internationally have demonstrated that melatonin can promote the generation of osteoblasts and osteoclasts, thereby increasing bone density and improving symptoms of osteoporosis. This article reviews the role of melatonin in the prevention of PMOP, aiming to provide new ideas for the diagnosis and treatment of PMOP.

Objective:To analyze the carriage status, subtype distribution and flanking gene sequence characteristics of oxacillinases (OXA enzyme) in 241 clinical strains of Pseudomonas aeruginosa, and assess their roles in the drug resistance of Pseudomonas aeruginosa and ability to horizontally transfer across species. Methods:Clinical P. aeruginosa isolates were collected from four hospitals in Sanya, Tangshan, Zhangjiakou, and Beijing. The prevalence of oxacillinases and their flanking gene sequences was analyzed by whole-genome sequencing (NGS) and bioinformatic approaches. Results:A total of 241 isolates of P. aeruginosa were gathered, and 35 blaOXA subtypes were identified through screening of 252 blaOXA genes. These genes were classified into three subfamilies: blaOXA-50-like (241, 95.6%), blaOXA-1-like (9, 3.6%) and blaOXA-10-like (2, 0.8%). Among these, 11 subtypes (11, 31.4%) were novel blaOXA subtypes. Nine of these belonged to the blaOXA-50-like subfamily and were designated as blaOXA-1244, blaOXA-1245, blaOXA-1246, blaOXA-1250, blaOXA-1252, blaOXA-1253, blaOXA-1254, blaOXA-1255, and blaOXA-1256. The remaining two belonged to the blaOXA-10-like subfamily and were named blaOXA-1247 and blaOXA-1248. Compared to the amino acid sequence of OXA-10, the newly identified subtype OXA-1247 exhibited a mutation at position 117, where a valine was replaced by a leucine. This change was thought to improve the enzyme′s ability to hydrolyze carbapenems. In the analysis of the flanking sequences of the blaOXA genes, Class I integrons were identified in four bacterial strains. The variable regions of these integrons carried three distinct patterns of resistance gene cassettes: aac( 6′) -Ib-blaOXA-1247-ant( 3′′) -Ia, aac( 6′) -Ib-blaOXA-1248 and aac( 6′) -Ib- blaIMP-45-blaOXA-1-catB3. Among these, the strain BJ2326 carried a class I integron that was connected to the downstream IS CR1 element to form a composite class I integron structure, additionally carrying the resistance gene blaPER-1. Out of the 223 non-wild-type P. aeruginosa strains, 127 strains exhibited non-wild-type profiles to the four beta-lactam antibiotics MEM, CAZ, FEP, and TZP, with the combination of MEM+CAZ+FEP being the most prevalent, representing 57.0% of the total. Conclusions:The blaOXA genes in 241 clinical P. aeruginosa strains showed diversity. Some blaOXA genes had a co-transfer risk with the metallo-β-lactamase resistance gene blaIMP-45. Among the 11 newly discovered blaOXA subtypes, the new subtype OXA-1247 may have carbapenemase activity and potential for horizontal transfer.