How to promote high-quality wound healing is a common problem for plastic surgery and burn physicians. In recent years, numerous animal studies have demonstrated that mesenchymal stem cell-derived exosomes promote wound repair through multiple mechanisms and are promising cell-free therapeutic agents with broad prospect of application. How to enhance the therapeutic efficacy of exosomes, optimize their drug delivery strategy, and improve their biological properties are the challenges to be overcome in order to move from basic research to clinical application of exosome therapy for wound repair. This article focuses on methods to improve the wound repair potential of mesenchymal stem cell-derived exosomes, and reviews the recent research advances on improving the therapeutic efficacy of mesenchymal stem cell-derived exosomes in wound repair from three aspects, including pretreatment of parental mesenchymal stem cells, hydrogel bio-scaffold loaded with exosomes, and engineered exosomes, to provide a reference for further clinical studies.

Objective:To investigate the effects of polycyclic aromatic hydrocarbons (PAHs) exposure on the prognosis of high risk human papillomavirus (HR-HPV) infection.Methods:In this prospective study, 564 patients with low-grade cervical intraepithelial neoplasia confirmed by pathology were selected from the natural cohort population established by our research group in Shanxi province in 2014. Based on the baseline data of demographic characteristics and factors related to HPV infection, the concentrations of 1-hydroxypyrene in urine samples of the patients were determined by high performance liquid chromatography to define the exposure level of PAHs. At baseline survey and follow-up after 24 months, flow-through hybridization was used to detect HPV infection types, and to evaluate the prognosis of HR-HPV (persistent infection, negative conversion, positive conversion and persistent negative status).Results:Of the 564 subjects, 483 completed the follow-up, with a follow-up rate of 85.6% (483/564). Among them, the persistent infection rate was 52.4% (75/143), the persistent homotype infection rate was 35.7% (51/143), the negative conversion rate was 47.6% (68/143), the positive conversion rate was 19.7% (67/340), and the persistent negative rate was 80.3% (273/340). The follow-up results showed that the persistent infection rate (a RR=3.22, 95% CI: 1.85-5.62) and positive conversion rate (a RR=2.84, 95% CI: 1.64-4.94) of HR-HPV in high PAHs exposure group were higher than those in low PAHs exposure group, while the persistent negative rate (a RR=0.55, 95% CI: 0.43-0.70) of HR-HPV in high PAHs exposure group were lower than those in low PAHs exposure group. Based on restrictive cubic spline analysis, the results showed that the effects of PAHs exposure on persistent HR-HPV infection and persistent homotype infection showed an ascending linear dose-response relationship, while on HR-HPV positive conversion and persistent negative status showed an ascending and declining nonlinear dose-response relationship respectively ( P<0.01). Conclusions:High PAHs exposure could promote persistent HR-HPV infection and persistent homotypic infection. Reducing PAHs exposure might conducive to HR-HPV continuous negative maintenance. Active prevention and control of PAHs exposure is of great significance to prevent HR-HPV infection and persistent infection.

Objective:To investigate the effect of red blood cell folate on the prognosis of high-risk human papillomavirus (HR-HPV) infection .Methods:A total of 564 participants with low-grade cervical intraepithelial neoplasias (CINⅠ) were selected from the community-based married women cohort established in 2014. The general baseline information and factors related to HPV infection were collected. Meanwhile, HPV genotyping and levels of folate were measured. The subjects were divided into different levels of exposure group according to the folate levels and followed up for 24 months to observe the changes of HR-HPV infection status. There were four changes, including persistent infection, infection turned negative, from negative to positive and constant negative by comparing HR-HPV infection status at baseline and follow-up to 24 months.Results:483 participators completed 24 months of follow-up observation, with a follow-up rate of 85.64% (483/564). The rates of persistent infection, infection turned negative, from negative to positive, and the constant negative were 52.45% (75/143), 47.55% (68/143), 19.71% (67/340), 80.29% (273/340), respectively. Our results demonstrated that the risk of persistent infection (a RR=2.50, 95% CI: 1.55-4.02) and from negative to positive (a RR=4.55, 95% CI: 2.52-8.23) in the low level of folate were significantly higher than that in the high level of folate, especially the risk of homotype persistent infection (a RR=2.72, 95% CI: 1.51-4.90). The risk of persistent infection (trend χ2=20.62, P<0.001), from negative to positive (trend χ2=31.76, P<0.001), persistent homotypic infection (trend χ2=20.09, P<0.001) increased with the decrease of red blood cell folate level. On the contrary, no similar results were found in persistent heterotypic infection. Conclusions:A low level of red blood cell folate could increase the risk of HR-HPV persistent infection and from negative to positive. In women with HR-HPV infection, the risk of persistent homotypic infection is higher.

Objective To analyze the epidemiological characteristics and epidemic situation of children with Kashin-Beck disease (KBD) in China,and provide the basis for formulating prevention and control measures. Methods Fixed-point monitoring,moving-point monitoring,and full coverage of monitoring were promoted successively from 1990 to 2023. Some children (7-12 years old) underwent clinical and right-hand X-ray examinations every year. According to the KBD diagnosis criteria,clinical and X-ray assessments were used to confirm the diagnosis. Results In 1990,the national KBD detectable rate was 21.01％. X-ray detection decreased to below 10％ in 2003 and below 5％ in 2007. Between 2010 and 2018,the prevalence of KBD in children was less than 0.4％,which fluctuated at a low level,and has decreased to 0％ since 2019. Spatial epidemiological analysis indicated a spatial clustering of adult patients prevalence rate in the KBD areas. Conclusion The evaluation results of the elimination of KBD in China over the last 5 years showed that all villages in the monitored areas have reached the elimination standard. While the adult KBD patients still need for policy consideration and care.

High Altitude Military Hygiene is the professional core course of high-altitude medicine, which is significant to the cultivation of military medical talents urgently needed by plateau troops. Under the background of "golden course" construction and army curriculum reform, aiming at the problems such as outdated content of course materials, single teaching mode and insufficient capacity of practical courses, we actively explored the effective path of "golden course" construction, including the renovation of the curriculum-construction concept, the optimization and reorganization of the teaching content, the expansion of case teaching and equipment teaching methods, and the implementation of curriculum ideological and political education and examination reforms. The reform has further improved the learning effect of students and the level of curriculum construction, and also provided beneficial reference for the construction of similar courses in military colleges and universities.

Objective To investigate the changes in blood microbiota in patients with high altitude polycythemia(HAPC)and the correlation with the risk of HAPC.Methods A cross-sectional trial was carried out among 41 HAPC patients(HAPC group)and 41 healthy plateau individuals(control group)who took physical examination in the Health Management Department of No.953 Hospital of PLA Army in 2021.High-throughput sequencing technology was used to detect the V3-V4 variable region of the 16S ribosomal RNA(16S rRNA)gene in the blood smaples,and the composition and difference of the blood microbiota were compared and analyzed between the 2 groups.Results All the participants were male and Han people,and there were no significant differences in baseline data such as age,body mass index and plateau migration time between the 2 groups(P＞0.05).The α-diversity of blood microbiota in the HAPC group,including the Simpson index(0.931±0.005 vs 0.907±0.008,P＜0.05),Goods Coverage index(0.998±0.001 vs 0.997±0.001,P＜0.001)and Pielou index(0.597±0.011 vs 0.567±0.009,P＜0.05)were significantly higher than those in the control group.Meanwhile,obvious difference was observed in the β diversity between the 2 groups(P＜0.01).The relative abundance analysis of bacteria showed that Pelomonas(0.046±0.004 vs 0.033±0.003,P＜0.05),Azospirillum(0.046±0.006 vs 0.021±0.003,P＜0.01),Acidovorax(0.032± 0.003 vs 0.019±0.002,Azospirillum(0.046±0.006 vs 0.021±0.003,P＜0.01)and Acidovorax(0.032± 0.003 vs 0.019±0.002,P＜0.05)were statistically higher in the HAPC group than the control group.LEfSe analysis showed that the characteristic blood microbiota of the HAPC group were α-Proteobacteria,and those of control group were Trichospiridae.Conclusion Significant changes are found in diversity,relative abundance and characteristic bacteria of the blood microbiota between the HAPC patients and healthy people at the high altitude,which might be closely associated with the occurrence and development of HAPC.

【Objective】 This paper screened the factors that may influence the spatial differentiation of Neutrophil-to-lymphocyte ratio （NLR） reference values in healthy adults in China and explored the trend of NLR reference values in China. 【Methods】 For this research， we collected the NLR of 162 681 healthy adults from 62 cities in China. Spearman regression analysis was used to analyze the correlation between NLR and 25 geography secondary indexes. We extracted 9 indexes with significant correlation， built a random forest （RF） model， and predicted the country’s urban healthy adults’ NLR reference value. By using the disjunctive Kriging method， we obtained the geographical distribution of NLR reference value of healthy adults in China. 【Results】 The reference value of NLR of healthy adults in China was significantly correlated with the 9 secondary indexes， namely， altitude， sunshine duration， annual average temperature， annual average relative humidity， annual temperature range， annual average wind speed， content of organic matter in topsoil， cation exchange capacity in topsoil （clay）， and total amount of CaSO4 in soil. The geographical distribution of NLR values of healthy adults in China showed a trend of being higher in Southeast China and lower in Northwest China， higher in coastal areas and lower in inland areas. 【Conclusion】 This study lays a foundation for further research on the mechanism of different influencing factors on the reference value of NLR index. A random forest model composed of significant influencing factors has been established to provide the basis for formulating reference criteria for the prognostic factors of the novel coronavirus using NLR reference values in different regions.

ObjectiveTo investigate the clinicopathological features， diagnosis and treatment methods， and prognosis of gallbladder sarcomatoid carcinoma （GBSC）. MethodsA retrospective analysis was performed for the clinical data of 16 patients with GBSC who were admitted to The First Affiliated Hospital of Zhengzhou University from January 2015 to April 2023， including general information， clinical manifestations， imaging features， pathological features， and treatment modality， and follow-up was performed for all patients. The Kaplan-Meier method was used to perform the survival analysis and plot the survival curve， and the Log-rank test was used for comparison between groups. ResultsAmong the 16 patients， there were 6 male patients and 10 female patients， with a mean age of 62.9±8.4 years. The main clinical manifestations were right upper abdominal pain in 13 patients （81.3%）， nausea in 5 patients （31.3%）， abdominal distension in 4 patients （25.0%）， poor appetite in 3 patients （18.8%）， weakness in 2 patients （12.5%）， fever in 2 patients （12.5%）， and jaundice in 1 patient （6.3%）， and 3 patients were asymptomatic and were found to have this disease by physical examination. Of all patients， 81.3% （13/16） were in the advanced stage （stage Ⅲ/Ⅳ） at the time of initial diagnosis. Histopathological examination showed that some cancer cells were spindle-shaped under the microscope， with marked nuclear division and noticeable heteromorphism. Immunohistochemistry showed a positive expression rate of 100% （16/16） for Vimentin， AE1/AE3， and CK8/18， and Ki-67 proliferation index was highly expressed in 81.3% （13/16） of the patients （≥50%）， with a median of 70% （range 20%‍ ‍—‍ ‍90%）. All 16 patients underwent surgical treatment， with radical surgery in 11 patients and palliative surgery in 5 patients， among whom 9 received R0 resection， 2 received R1 resection， and 5 received R2 resection， and 7 patients received adjuvant therapy after surgery. Effective follow-up was achieved for all 16 patients， with a follow-up time of 0.5‍ ‍—‍ ‍26.0 months and a median follow-up time of 11.0 months. By the end of follow-up， 2 patients survived and 14 patients died due to tumor recurrence or metastasis， with a median survival time of 10.0 months， and the 1- and 2-year cumulative survival rates after surgery were 31.3% and 8.3%， respectively. The prognostic analysis showed that TNM stage （χ²=6.727， P=0.009）， surgical approach （χ²=7.508， P=0.006）， margin condition （χ²=7.934， P=0.005）， and adjuvant therapy （χ²=4.608， P=0.032） were associated with the prognosis of patients. ConclusionThe clinical manifestations of GBSC lack specificity， and a confirmed diagnosis relies on immunohistochemical analysis. Most patients are in the advanced disease at the time of initial diagnosis and tend to have a poor prognosis. There are currently no targeted therapies for this disease， and radical surgery with negative margins and adjuvant therapy can improve the survival rate of patients.