Umbilical cord mesenchymal stem cells (UC-MSCs) have been widely used in regenerative medicine, but there is limited research on the stability of UC-MSCs formulation during production. This study aims to assess the stability of the cell stock solution and intermediate product throughout the production process, as well as the final product following reconstitution, in order to offer guidance for the manufacturing process and serve as a reference for formulation reconstitution methods. Three batches of cell formulation were produced and stored under low temperature (2-8 ℃) and room temperature (20-26 ℃) during cell stock solution and intermediate product stages. The storage time intervals for cell stock solution were 0, 2, 4, and 6 h, while for intermediate products, the intervals were 0, 1, 2, and 3 h. The evaluation items included visual inspection, viable cell concentration, cell viability, cell surface markers, lymphocyte proliferation inhibition rate, and sterility. Additionally, dilution and culture stability studies were performed after reconstitution of the cell product. The reconstitution diluents included 0.9% sodium chloride injection, 0.9% sodium chloride injection + 1% human serum albumin, and 0.9% sodium chloride injection + 2% human serum albumin, with dilution ratios of 10-fold and 40-fold. The storage time intervals after dilution were 0, 1, 2, 3, and 4 h. The reconstitution culture media included DMEM medium, DMEM + 2% platelet lysate, 0.9% sodium chloride injection, and 0.9% sodium chloride injection + 1% human serum albumin, and the culture duration was 24 h. The evaluation items were viable cell concentration and cell viability. The results showed that the cell stock solution remained stable for up to 6 h under both low temperature (2-8 ℃) and room temperature (20-26 ℃) conditions, while the intermediate product remained stable for up to 3 h under the same conditions. After formulation reconstitution, using sodium chloride injection diluted with 1% or 2% human serum albumin maintained a viability of over 80% within 4 h. It was observed that different dilution factors had an impact on cell viability. After formulation reconstitution, cultivation in medium with 2% platelet lysate resulted in a cell viability of over 80% after 24 h. In conclusion, the stability of cell stock solution within 6 h and intermediate product within 3 h meets the requirements. The addition of 1% or 2% human serum albumin in the reconstitution diluent can better protect the post-reconstitution cell viability.

After entering the body from the drug delivery site, antitumor nanomedicines need to cross a series of physiopathological barriers to reach the target site of action to effectively exert antitumor therapeutic effects. The ligand modification strategy is a classic method to enhance the efficiency of nanomedicine delivery in vivo, but the contradiction between the single ligand modification strategy, which is characterized by unity and stage, and the in vivo delivery process, which is characterized by versatility and whole-process characteristics, determines that nanomedicines modified by a single ligand alone cannot satisfy the target efficacy requirements. Therefore, the use of multiligand combinatorial modification strategies by virtue of nanomedicine surface area advantages is key to advancing the next generation of smart nanomedicines. In this paper, on the basis of summarizing and classifying the commonly used functional ligands for in vivo delivery, the advantages and research progress of multiligand combination modification of antitumor nanomedicines are discussed with special focus, and the multiligand combination modification is classified as synergistic and complementary according to the combination of the ligands, which is of great significance to ensure that antitumor nanomedicines can overcome the multiple physiopathological barriers to achieve precise delivery.

Objective:To understand the infection status, epidemiological characteristics and drug resistance of Diarrheagenic Escherichia coli (DEC) in Shanghai and provide evidence for the disease surveillance. Methods:The epidemiological data of diarrhea cases in Shanghai from 2016 to 2022 were collected from Shanghai Diarrhea Comprehensive Surveillance System, and stool samples were collected from the cases for DEC detection. The drug resistance data was obtained from Chinese Pathogen Identification Network. Statistical analysis was conducted by using χ2 and fisher test. Results:In 24 883 diarrhea cases detected during 2016-2022, the DEC positive rate was 9.13% (2 271/24 883), the single DEC positive rate was 8.83% (2 197/24 883) and the mixed DEC positive rate was 0.30% (74/24 883). The main type of DEC was Enterotoxigenic Escherichia coli (ETEC) [4.33% (1 077/24 883)]. The DEC positive rate was highest in people aged ≤5 years 18.48% (22/119). The annual peak of DEC positive rate was observed during July - September [5.91% (1 470/24 883)]. The DEC positive rate were 9.47% (554/5 847) and 9.02% (1 717/19 036) in urban area and in suburbs, respectively, Enteroaggregative Escherichia coli (EAEC) [3.98% (233/5 847)] and ETEC [4.56% (868/19 036)] were mainly detected. From 2016 to 2019, the DEC positive rate was 9.42% (1 821/19 330), while it was 8.10% (450/5 553) from 2020 to 2022, the main DEC types were ETEC (4.87%, 941/19 330) and EAEC (4.70%, 261/5 553). The multi-drug resistance rate was 40.21% (618/1 537). The top three antibiotics with high drug resistance rates were ampicillin [64.74% (995/1 537)], nalidixic acid [58.49% (899/1 537)] and tetracycline [45.09% (693/1 537)]. Conclusions:Compared with 2016- 2019, a decrease in DEC detection rate was observed during 2020-2022, and the main type of DEC detected shifted from ETEC to EAEC. The prevalence of multi-drug resistance was severe. Therefore, it is necessary to further strengthen the surveillance for DEC drug resistance and standardize the use of clinical antibiotics.

Growth/differentiation factor-5 (GDF-5) belongs to transforming growth factor-β (TGF-β) family, which is expressed in bone, cartilage, heart, brain, kidney, skeletal muscle and tendon, liver, fat and other organs and tissues as well. GDF-5 binds to receptor BMPR-I/BMPR-II and activates different signaling pathways such as smad1/5/8, PI3K/Akt, p38-MAPK. For a long time, numerous studies have shown that GDF-5 plays an important role in protecting joints. However, researchers have found GDF-5 also plays significant biological functions in other organs. For example, GDF-5 improves cardiac function by reducing oxidative stress and fibrosis in infarcted hearts. GDF-5 can also reduce oxidative stress in the brain and increase the number of neurons in effort to delay the progression of Alzheimer’s disease and Parkinson’s disease. It is a situation, research on GDF-5, at present, mainly focuses on the growth and repair of bone, cartilage and tendons, while there are few reports on its biological effects in other organs. Therefore, this article reviews and summarizes the research progress on GDF-5 and metabolic diseases in recent years in order to provide new insights and theoretical basis for the role of GDF-5 in improving metabolic diseases.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

Bone organoids can simulate the complex structure and function of the bone tissues, which makes them a frontier technology in organoid researches. Bone organoids show a tremendous potential of applications in bone disease modeling, bone injury repair, and medicine screening. Although advancements have been made so far in constructing bone organoids with functional structures like mineralization, bone marrow, trabecular bone, callus, woven bone, etc, the researches in this field are confronted with numerous challenges such as lack of standardized construction strategies and unified evaluation criteria, which limits their further promotion and application. To standardize researches in bone organoids, the Orthopedic Expert Committee of Geriatric Branch of Chinese Association of Gerontology and Geriatrics, the Youth Osteoporosis Group of Orthopedic Branch of Chinese Medical Association, the Osteoporosis Group of Orthopedic Surgeon Branch of Chinese Medical Doctor Association, and the Osteoporosis Committee of Shanghai Association of Integrated Traditional Chinese and Western Medicine organized related experts to formulate Expert consensus on the construction, evaluation, and application of bone organoids ( version 2024) based on an evidence-based approach. A total of 17 recommendations were put forth, aiming to standardize researches and clinical applications of bone organoids and enhance their value in scientific research and clinical practice.

Objective This study aimed to explore the diagnostic concordance of fractional flow reserve(FFR)and quantitative flow ratio(QFR)and the characteristics affecting this concordance.Methods Patients with non-acute myocardial infarction admitted to the Department of Cardiology,Peking University Third Hospital between January 2019 and December 2021 were enrolled.The patients were divided into four groups:FFR+/QFR+and FFR-/QFR-,FFR+/QFR-and FFR-/QFR+with FFR or QFR≤0.80 as positive and＞0.80 as negative.Using FFR as the gold standard,the diagnostic value of QFR was analyzed,and differences in clinical features and pathological characteristics among the groups were compared.Results A total of 236 patients were included.The mean age was(64.48±9.63)years,and 67.8％were male.All patients had 30％-70％coronary stenosis.The consistency rate of QFR and FFR was 78.0％(n=184),and the Person correlation coefficient was 0.557(P＜0.001).Among FFR+patients,the minimum lumen diameter was larger[(1.56±0.34)mm vs.(1.39±0.31)mm,P=0.019],lesion length was shorter[(21.37±11.73)mm vs.(36.86±18.09)mm,P＜0.001],and coronary angiography-based index of microcirculartory resistance(AMR)was higher[(277.50±28.87)mmHg·s/m vs.(178.02±49.13)mmHg·s/m,P＜0.001]in the disconcordance group.Multivariate regression analysis suggested that AMR[OR 0.93,95％CI 0.88-0.99,P=0.030]and lesion length[OR 1.27,95％CI 1.01-1.60,P=0.045]were independent predictors of disconcordance.In the FFR-group,the lesion length was longer[(33.08±16.05)mm vs.(21.40±13.36)mm,P=0.020],and AMR[(169.66±24.01)mmHg·s/m vs.(265.95±44.78)mmHg·s/m,P＜0.001]and low-density lipoprotein-C[1.57(1.10,1.97)mmol/L vs.2.15(1.79,2.74)mmol/L,P=0.031]were lower in the disconcordance group.No statistically significant variables were identified by multivariate regression.Conclusions QFR had high diagnostic value compared with FFR.In the FFR+group,AMR and lesion length may have affected the diagnostic consistency of QFR and FFR.The study provided more evidence for the clinical application of QFR.

Investigating the species/biovars,distribution patterns,and genetic correlations of Brucella from sheep in north-west China is critical to reveal the population and epidemiological characteristics of the Brucella melitensis.In this study,con-ventional identification and AMOS-PCR were used to determine the species/biovars of Brucella isolated from 13 regions in northwest China.MLST and MLVA-16 genotyping methods were used to analyze the genetic characteristics of the strains.Con-ventional identification and AMOS-PCR detection revealed that 59 Brucella melitensis were isolated in this study,in-cluding 22 strains from Inner Mongolia,17 strains from Xin-jiang,13 strains from Gansu,and 7 strains from Qinghai,of which 58 strains were B.melitensis biovar 3,and one strain was B.melitensis biovar 1.MLST analysis indicated that 90％(53/59)of B.melitensis were of ST8 sequence type,the dominant epidemic population.The MLVA-11 survey demonstrated that 59 B.melitensis strains clustered into six MLVA-11 genotypes,and 87％of the strains were of MLVA-11 genotype 116.Therefore,the predominant strains in the northwest region were from the Eastern Mediterranean lineage.MLVA-16 divided 59 strains of B.melitensis into 40 gen-otypes,eight of which were shared genotypes.Each genotype was composed of two to seven strains from the same region,thereby indicating that the cases of each shared genotype were outbreaks from a common source of infection.All shared MLVA-16 genotypes comprised strains from the same province,thus indicating apparent regional clustering characteristics of strains in each province.In a genetic comparison between populations and isolated strains from the spleens of sheep,multiple identical MLVA-16 genotypes were found to be composed of strains from different hosts.These findings indicated a transmission path-way from sheep/goats to humans.B.melitensis biovar 3 was the main pathogen causing animal brucellosis in the northwest re-gion,and infected sheep were the main brucellosis infection source in the regional population.The ST8 strains were the domi-nant epidemic population,and the MLVA genotype of strains in each region showed clear regional clustering characteristics.

Objective:To investigate the effect of genetic polymorphism of MTHFR C677T (rs1801133) on methotrexate (MTX) related toxicity in pediatric mature B-cell lymphoma patients. Methods:Fifty-eight intermediate and high risk patients under 18 years of age with mature B-cell lymphoma who received 5 g/m2 MTX (24 h intravenous infusion) in Sun Yat-sen University Cancer Center from August 2014 to December 2021 were included,and their toxicity of high-dose MTX (HD-MTX) were monitored and analyzed. Results:Among the 58 pediatric patients,the number of CC,CT,and TT genotypes for MTHFR C677T was 33,19 and 6,respectively. A total of 101 courses of HD-MTX therapy were counted,of which plasma MTX level>0.2 μmol/L at 48 h post-MTX infusion were observed in 35 courses,≤0.2 μmol/L in 66 courses. Inter-group comparison showed that plasma MTX level>0.2 μmol/L at 48 h post-MTX infusion increased the risk of developing oral mucositis (P<0.05). Compared with wild-type (CC genotype),patients in the mutant group (CT+TT genotype) were more likely to develop myelosuppression,manifested as anemia,leucopenia,neutropenia and thrombocytopenia. However,plasma MTX level at 48 h was not associated with MTHFR C677T gene polymorphism. Conclusion:The risk of developing oral mucositis in children with mature B-cell lymphoma is associated with plasma MTX concentration. Polymorphism of MTHFR C677T gene is not related to plasma MTX concentration in children with mature B-cell lymphoma,but is related to grade Ⅲ to Ⅳ hematological toxicity.

The presence of food-borne pathogenic bacteria poses a severe threat to human health. Therefore,it is essential to develop effective methods for bacteria detection. Herein,a method based on digital polymerase chain reaction (PCR) chip was developed for rapid and effective detection of three kinds of common food-borne bacteria (Staphylococcus aureus,Salmonella typhimurium and Listeria monocytogenes). Driven by centrifugal force,samples could be easily loaded and digitized in 15 min. PCR results showed that the positive microchambers in the chip could be identified after 25 thermal cycles. The chip had advantages in the quantitative detection of bacterial nucleic acid at low concentration,which could effectively avoid false negative results. Multiple detection of bacterial samples with concentration of 105-108 CFU/mL could also be realized using this chip. Compared with fluorescent quantitative PCR,this method had higher accuracy and sensitivity,especially for detection of targets at low concentration.