One of the technical bottlenecks limiting the high yield of 1,4-butanediamine is the insufficient tolerance of strains to 1,4-butanediamine. Enhancing the tolerance of strains to 1,4-butanediamine is therefore a primary challenge that needs to be addressed for the construction of strains with high yields of 1,4-butanediamine. Staphylococcus pasteuri 326180 exhibits exceptional tolerance to high-concentration 1,4-butanediamine, serving as both an ideal model for studying the mechanism underlying the 1,4-butanediamine tolerance and a novel host for constructing strains capable of efficiently producing 1,4-butanediamine. However, for both the research on the tolerance mechanism and the modification of chassis strains, gene editing of S. pasteuri needs to be carried out at the molecular level. The research objective of this paper is to establish a genetic manipulation system for S. pasteuri, laying foundation for subsequent studies on tolerance mechanism and the modification of chassis strains. This study systematically optimized the electroporation conditions, including key parameters such as the growth phase of cells, electric field strength, electroporation buffer, and recovery medium, successfully establishing an electroporation method for S. pasteuri. Additionally, we constructed the gene editing plasmid pCpfOA by replacing the resistance expression cassette, optimized the selection markers for gene editing, and finally established a CRISPR/Cpf1-based gene editing technology for S. pasteuri, achieving an editing efficiency of 90%. The genetic manipulation system of S. pasteuri established in this study provides technical support for research into the tolerance mechanism of this bacterium and the genetic modification of chassis strains.
Staphylococcus/drug effects* ; Gene Editing/methods* ; Electroporation/methods* ; Plasmids/genetics* ; CRISPR-Cas Systems ; Genetic Engineering/methods*

Room temperature stored platelets are associated with a higher risk of sepsis and related fatality. The risk of bacterial contamination of platelets is a leading risk of infection from blood transfusion. U.S. Food and Drug Administration recently issued a guidance on bacterial risk control strategies for blood collection establishments and transfusion services to enhance the safety and availability of platelets for transfusion. The prevention and control strategies in the guidance would be informative and instructive for further development of risk control strategies of platelet bacterial contamination in China.

Background: and Purpose This study aimed to investigate the association between residual inflammatory risk (RIR) and vulnerable plaques using high-resolution magnetic resonance imaging (HRMRI) in symptomatic intracranial atherosclerotic stenosis (ICAS). Methods: This retrospective study included 70%–99% symptomatic ICAS patients hospitalized from January 2016 to December 2022. Patients were classified into four groups based on high-sensitivity C-reactive protein (hs-CRP) and low-density lipoprotein cholesterol (LDL-C): residual cholesterol inflammatory risk (RCIR, hs-CRP ≥3 mg/L and LDL-C ≥2.6 mmol/L), RIR (hs-CRP ≥3 mg/L and LDL-C <2.6 mmol/L), residual cholesterol risk (RCR, hs-CRP <3 mg/L and LDL-C ≥2.6 mmol/L), and no residual risk (NRR, hs-CRP <3 mg/L and LDL-C <2.6 mmol/L). Vulnerable plaque features on HRMRI included positive remodeling, diffuse distribution, intraplaque hemorrhage, and strong enhancement. Results: Among 336 included patients, 21, 60, 58, and 197 were assigned to the RCIR, RIR, RCR, and NRR groups, respectively. Patients with RCIR (adjusted odds ratio [aOR], 3.606; 95% confidence interval [CI], 1.346–9.662; P=0.011) and RIR (aOR, 3.361; 95% CI, 1.774–6.368, P<0.001) had higher risks of strong enhancement than those with NRR. Additionally, patients with RCIR (aOR, 2.965; 95% CI, 1.060–8.297; P=0.038) were more likely to have intraplaque hemorrhage compared with those with NRR. In the sensitivity analysis, RCR (aOR, 2.595; 95% CI, 1.201–5.608; P=0.015) exhibited an additional correlation with an increased risk of intraplaque hemorrhage. Conclusion In patients with symptomatic ICAS, RIR is associated with a higher risk of intraplaque hemorrhage and strong enhancement, indicating an increased vulnerability to atherosclerotic plaques.

Background: and Purpose This study aimed to investigate the association between residual inflammatory risk (RIR) and vulnerable plaques using high-resolution magnetic resonance imaging (HRMRI) in symptomatic intracranial atherosclerotic stenosis (ICAS). Methods: This retrospective study included 70%–99% symptomatic ICAS patients hospitalized from January 2016 to December 2022. Patients were classified into four groups based on high-sensitivity C-reactive protein (hs-CRP) and low-density lipoprotein cholesterol (LDL-C): residual cholesterol inflammatory risk (RCIR, hs-CRP ≥3 mg/L and LDL-C ≥2.6 mmol/L), RIR (hs-CRP ≥3 mg/L and LDL-C <2.6 mmol/L), residual cholesterol risk (RCR, hs-CRP <3 mg/L and LDL-C ≥2.6 mmol/L), and no residual risk (NRR, hs-CRP <3 mg/L and LDL-C <2.6 mmol/L). Vulnerable plaque features on HRMRI included positive remodeling, diffuse distribution, intraplaque hemorrhage, and strong enhancement. Results: Among 336 included patients, 21, 60, 58, and 197 were assigned to the RCIR, RIR, RCR, and NRR groups, respectively. Patients with RCIR (adjusted odds ratio [aOR], 3.606; 95% confidence interval [CI], 1.346–9.662; P=0.011) and RIR (aOR, 3.361; 95% CI, 1.774–6.368, P<0.001) had higher risks of strong enhancement than those with NRR. Additionally, patients with RCIR (aOR, 2.965; 95% CI, 1.060–8.297; P=0.038) were more likely to have intraplaque hemorrhage compared with those with NRR. In the sensitivity analysis, RCR (aOR, 2.595; 95% CI, 1.201–5.608; P=0.015) exhibited an additional correlation with an increased risk of intraplaque hemorrhage. Conclusion In patients with symptomatic ICAS, RIR is associated with a higher risk of intraplaque hemorrhage and strong enhancement, indicating an increased vulnerability to atherosclerotic plaques.

BACKGROUND:Psoralen has a strong anti-osteoporotic activity and may have a restorative effect on chemotherapy-induced osteoporosis. OBJECTIVE:To explore the restorative effect of psoralen on the osteogenic differentiation of bone marrow mesenchymal stem cells in mice inhibited by cyclophosphamide and its mechanism. METHODS:C57BL/6 mouse bone marrow mesenchymal stem cells were isolated and cultured.Effect of psoralen on viability of bone marrow mesenchymal stem cells was detected by MTT assay.Osteogenic induction combined with alkaline phosphatase staining was used to determine the optimal dose of psoralen to restore the osteogenic differentiation of bone marrow mesenchymal stem cells inhibited by cyclophosphamide.The mRNA expression levels of Runx2,alkaline phosphatase,Osteocalcin,osteoprotegerin,and Wnt/β-catenin signaling pathway-related genes Wnt1,Wnt4,Wnt10b,β-catenin,and c-MYC were measured by RT-qPCR at different time points under the intervention with psoralen.The protein expression of osteogenic specific transcription factor Runx2 and Wnt/β-catenin signaling pathway related genes Active β-catenin,DKK1,c-MYC,and Cyclin D1 was determined by western blot assay at different time points under the intervention with psoralen. RESULTS AND CONCLUSION:(1)There was no significant effect of different concentrations of psoralen on the viability of bone marrow mesenchymal stem cells.The best recovery of the inhibition of osteogenic differentiation of bone marrow mesenchymal stem cells caused by cyclophosphamide was under the intervention of psoralen at a concentration of 200 μmol/L.(2)Psoralen reversed the reduction in osteogenic differentiation marker genes Runx2,alkaline phosphatase,Osteocalcin and osteoprotegerin mRNA expression and Runx2 protein expression in bone marrow mesenchymal stem cells caused by cyclophosphamide conditioned medium.(3)Psoralen reversed the decrease in Wnt/β-catenin pathway-related genes Wnt4,β-catenin,c-MYC mRNA and Active β-catenin,c-MYC,and Cyclin D1 protein expression and the increase in DKK1 protein expression in bone marrow mesenchymal stem cells caused by cyclophosphamide conditioned medium.(4)The results showed that cyclophosphamide inhibited osteogenic differentiation of bone marrow mesenchymal stem cells in mice,and psoralen had a restorative effect on it.The best intervention effect was achieved at a concentration of 200 μmol/L psoralen,and this protective effect might be related to the activation of Wnt4/β-catenin signaling pathway by psoralen.

Objective:To investigate the risk factors associated with post-prematurity respiratory disease (PPRD) in very preterm infants.Methods:A prospective cohort study was conducted, enrolling 369 very preterm infants who were admitted to the neonatal intensive care unit of Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, within one week of birth from January 2019 to June 2023. Data on maternal and infant clinical characteristics, neonatal morbidities, and treatments during hospitalization were collected. The very preterm infants were divided into 2 groups based on whether they developed PPRD. Continuous variables were compared using Mann-Whitney U test, while categorical variables were compared using χ2 tests or continuity correction χ2 test. Multivariate Logistic regression analysis was used to identify the independent risk factors for PPRD in very preterm infants. Results:Among the 369 very preterm infants, 217 cases(58.8%) were male, with a gestational age of 30 (28, 31) weeks at birth and a birth weight of 1 320 (1 085, 1 590) g. Of these, 116 cases (31.4%) developed PPRD, while 253 cases (68.6%) did not. The very preterm infants in the PPRD group had a lower gestational age and lower birth weight (both, P<0.001). The PPRD group also had a higher proportion of males, lower Apgar scores at the 1 th minute after birth and the 5 th minutes after birth, a higher rate of born via cesarean delivery, and a higher incidence of bronchopulmonary dysplasia, more pulmonary surfactant treatment, longer durations of mechanical ventilation, longer total oxygen therapy, and lower Z-score for weight at discharge (all P<0.05). Multivariate Logistic regression analysis showed that gestational age ( OR=0.85, 95% CI 0.73-0.99, P=0.037), born via cesarean delivery ( OR=2.23, 95% CI 1.21-4.10, P=0.010), a duration of mechanical ventilation ≥7 days ( OR=2.51, 95% CI 1.43-4.39, P=0.001), and a Z-score for weight at discharge ( OR=0.82, 95% CI 0.67-0.99, P=0.040) were all independent risk factors for PPRD in very preterm infants. Conclusion:Very preterm infants with a small gestational age, born via cesarean section, mechanical ventilation ≥7 days, and a low Z-score for weight at discharge should be closely monitored for PPRD, and provided with standardized respiratory management after discharge.

The integration of artificial intelligence(AI)into medical practice has significantly impacted the field of cerebrovascular disease.AI algorithms are increasingly being employed to enhance the diagnosis and management of cerebrovascular conditions.However,the clinical application and accuracy of these AI tools require further rigorous evaluation.This review probes into the current applications of AI in diagnosis and decision-making in cerebrovascular disease,and explores the potential and challenges associated with their implementation.

Objective To investigate the effects and mechanisms of high-fat diet(HFD)-induced obesity on male ze-brafish reproductive function.Methods Adult male zebrafish were divided into normal diet(ND)group and HFD group.Growth and metabolic conditions were evaluated by measuring body weight,body length,BMI,organ index,and glucose/lipid lev-els.Reproductive capacity was assessed via sperm concentration,motility,fertilization rate,and testosterone levels.Testicular tissues from both of groups were subjected to transeriptomic sequencing(RNA-seq).And qRT-PCR was used to validate the expression of genes.Results Compared to male zebrafish in ND group,the ones in HFD group exhibited hepatic steatosis and glucose/lipid meta-bolic disorders(P＜0.05).Testicular structural disorganization,along with reduced testosterone levels,decreased gonadosomatic in-dex,and impaired sperm concentration and motility occurred in HFD group(P＜0.05).GO analysis revealed that differentially ex-pressed genes were enriched in spermatogenesis and ciliary system,while KEGG analysis highlighted metabolic related pathways(pu-rine metabolism,thyroid hormone synthesis,mTOR signaling)and cell adhesion molecules.Twenty key differentially expressed genes were validated by qRT-PCR,which confirmed the reliability of RNA-Seq results.Conclusion Impairment of reproductive function induced by HFD in zebrafish may be associated with three regulatory mechanisms including ciliary system,metabolic dysregulation,and aberrant cell adhesion molecule signaling.This study provides mechanistic insights and identifies potential therapeutic targets for clinical management of diet-associated infertility.

Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.

BACKGROUND:In vitro reconstruction of hair follicles depends on the self-assembly behavior of dermal papilla cells and keratinocytes during three dimensional co-culture,which is very similar to the development of hair follicle embryos.Therefore,hair follicle organoids can be used as a good model in vitro for basic research of hair follicle regeneration.Currently,wholly humanized follicle organoids cultured by biomimetic system have been successfully transplanted into animals.Research on hair follicle organoids makes it possible to regenerate hair follicles,but there is no uniform conclusion on the construction method,and there are still many challenges.OBJECTIVE:To review the current research progress of hair follicle organoids,summarize their culture methods and characterization,and expound their application prospects,so as to provide reliable basis for subsequent research,in order to promote its clinical transformation in tissue engineering and alopecia treatment.METHODS:CNKI and PubMed databases were searched by a computer,using"hair follicle regeneration,hair regeneration,organoid"as Chinese search terms and"hair growth,hair loss,hair regeneration,hair follicle,dermal papilla cell,organoid"as English search terms.The domestic and foreign literature on hair follicle organoids was reviewed and a total of 67 articles were included for follow-up analysis.RESULTS AND CONCLUSION:(1)Dermal papilla cells and keratinocytes from different sources can be used to construct hair follicle organoids in vitro to obtain mouse-derived,human-mouse chimeric and human-derived hair follicle organoids,which have been successfully used in rodent transplantation models.(2)A variety of programming methods,such as electrical stimulation,addition of recombinant protein,and dissociation of cell gene expression,can be used to promote hair follicle organoid such ashair follicle germ formation and hair shaft elongation.Simultaneously,the application of various 3D printing technologies has achieved controllable hair follicle organoid to the size of the quantity production,which greatly improves the production efficiency.(3)When melanocytes are added to the dissociated cell co-culture system,the problem of pigment deficiency in new hair follicles may be solved.When human umbilical vein endothelial cells are added,the new blood vessels in the cell aggregates can improve their nutrient supply and reduce necrosis in the central area.(4)As the technology of engineered hair follicle organoid gradually maturates,hair follicle organoids constructed from patient's autologous cells may be used for individualized treatment of severe alopecia.