BACKGROUND:3D-printed bone tissue engineering scaffolds have obvious advantages in the research and clinical treatment of bone defect repair.As one of the important raw materials for 3D printed bone scaffolds,poly-L-lactic acid has a great potential for application in performing bone defect repair,but clinical patients with different bone defect causative factors have different requirements for the comprehensive performance of poly-L-lactic acid bone scaffolds.OBJECTIVE:To summarize and review the development of 3D printing technology and poly-L-lactic acid scaffolds and the design strategies chosen for scaffolds for bone repair in the setting of bone diseases such as osteomyelitis,bone tumor,osteonecrosis,and osteoporosis.METHODS:Literature from CNKI,WanFang,PubMed,Science Direct,and Web of Science databases were searched and screened from 1994 to 2024.Search terms were"3D printing,polylactic acid,bone tissue engineering scaffold,osteomyelitis,bone tumor,osteonecrosis,osteoporosis,bone defect"in Chinese and English.The screened 62 articles were systematically summarized and analyzed.RESULTS AND CONCLUSION:(1)Poly-L-lactic acid is considered to be an ideal raw material for artificial bone scaffold design due to its non-toxicity,processability,biocompatibility,and ability to self-degrade in the human environment.The application of 3D printing technology has enabled poly-L-lactic acid bone scaffolds to meet the multilayered and porous structural design requirements of biomimetic artificial bone repair materials,and to optimize the mechanical properties for better bone repair.(2)According to different bone disease microenvironments,timely adjustment of the functional design of poly-L-lactic acid scaffolds is important for the comprehensive osteogenic efficacy of the scaffolds.The article discusses the application of poly-L-lactic acid scaffolds in bone disease environments such as osteomyelitis,bone tumor,osteonecrosis,and osteoporosis,and highlights the importance of rationally grasping the timing of bone disease treatment and bone tissue regeneration for bone defects caused by different bone diseases.(3)Although poly-L-lactic acid scaffolds show potential in bone repair,there are still some problems,such as the need to further optimize the structural design of the scaffolds to fit new bone regeneration,enhance the bioactivity of the scaffolds,and take into account other functions(e.g.,antimicrobial,anti-tumor,and anti-osteoporosis)in order to adapt to the needs of bone tissue repair in different pathological environments.

As a pivotal strategy to alleviate the shortage of organ donors, xenotransplantation has achieved remarkable advances in both pre-clinical and clinical studies in recent years, driven by continuous optimization of gene modification techniques and immunosuppressive regimens. Nevertheless, clinical translation still confronts formidable challenges, including rejection and heightened infection risks, which severely compromise long-term graft survival. Consequently, the role of immunosuppressive regimens in xenotransplantation has become increasingly prominent. This article summarizes the mechanisms underlying xenogeneic immune rejection, the latest developments in immunosuppressive regimens, cutting-edge strategies for inducing immune tolerance and the major hurdles facing clinical xenotransplantation. It delves into potential optimization strategies and directions for future clinical research, aiming to offer theoretical insights and practical guidance for the safe and effective application of clinical xenotransplantation.

BACKGROUND:3D-printed bone tissue engineering scaffolds have obvious advantages in the research and clinical treatment of bone defect repair.As one of the important raw materials for 3D printed bone scaffolds,poly-L-lactic acid has a great potential for application in performing bone defect repair,but clinical patients with different bone defect causative factors have different requirements for the comprehensive performance of poly-L-lactic acid bone scaffolds.OBJECTIVE:To summarize and review the development of 3D printing technology and poly-L-lactic acid scaffolds and the design strategies chosen for scaffolds for bone repair in the setting of bone diseases such as osteomyelitis,bone tumor,osteonecrosis,and osteoporosis.METHODS:Literature from CNKI,WanFang,PubMed,Science Direct,and Web of Science databases were searched and screened from 1994 to 2024.Search terms were"3D printing,polylactic acid,bone tissue engineering scaffold,osteomyelitis,bone tumor,osteonecrosis,osteoporosis,bone defect"in Chinese and English.The screened 62 articles were systematically summarized and analyzed.RESULTS AND CONCLUSION:(1)Poly-L-lactic acid is considered to be an ideal raw material for artificial bone scaffold design due to its non-toxicity,processability,biocompatibility,and ability to self-degrade in the human environment.The application of 3D printing technology has enabled poly-L-lactic acid bone scaffolds to meet the multilayered and porous structural design requirements of biomimetic artificial bone repair materials,and to optimize the mechanical properties for better bone repair.(2)According to different bone disease microenvironments,timely adjustment of the functional design of poly-L-lactic acid scaffolds is important for the comprehensive osteogenic efficacy of the scaffolds.The article discusses the application of poly-L-lactic acid scaffolds in bone disease environments such as osteomyelitis,bone tumor,osteonecrosis,and osteoporosis,and highlights the importance of rationally grasping the timing of bone disease treatment and bone tissue regeneration for bone defects caused by different bone diseases.(3)Although poly-L-lactic acid scaffolds show potential in bone repair,there are still some problems,such as the need to further optimize the structural design of the scaffolds to fit new bone regeneration,enhance the bioactivity of the scaffolds,and take into account other functions(e.g.,antimicrobial,anti-tumor,and anti-osteoporosis)in order to adapt to the needs of bone tissue repair in different pathological environments.

This study investigated the prevalence of canine ticks and the types of their carried pathogens in select cities of Liaon-ing Province,to provide a theoretical scientific basis for the prevention and control of ticks and tick-borne diseases.Canine ticks were collected from six cities in Liaoning Province(Shenyang,Dalian,Anshan,Chaoyang,Tieling,Dandong)and identified through a combination of morphological and molecular biology methods.PCR was used to detect five tick pathogens:Rickettsia,Borrelia burgdor-feri,Babesia,Pseudomonas aeruginosa,and Ehrlichia.Canine ticks were prevalent primarily in Liaoning Province from April to June.The collected ticks included 456 Haemaphysalis longicornis,70 Ixodes persulcatus,and 31 Rhicephalus sanguineus.Three tick borne pathogens,Ehrlichia,Borrelia burgdorferi,and Rickettsia,were detected,whereas no Babesia or Pseudomonas were detected.The to-tal detection rate of Ehrlichia(46.85%),which is significant difference with total detection rate of Borrelia burgdorferi(10.81%)(χ2=33.392,P<0.05),but insignificant difference with total detection rate of Rickettsia(34.23%)(χ2=3.370,P>0.05),Both Eh-rlichia and Rickettsia were distributed in the six cities.Haemaphysalis longicornis was the dominant tick species parasite on the surfaces of dogs in Liaoning Province.The main tick borne pathogens in dogs in Liaoning Province were Ehrlichia and Rickettsia.

Kidney transplantation is an effective treatment for end-stage renal disease.However,post transplantation diabetes mellitus(PTDM)is a common complication after kidney transplantation,affecting 10%to 40%of recipients and increasing the risk of cardiovascular disease,infections,sepsis and other conditions.The pathogenesis of PTDM is complex,including pancreatic β-cell dysfunction and insulin resistance.Tacrolimus,a commonly used immunosuppressive drug,is an independent risk factor for PTDM.Its mechanisms include damaging pancreatic β-cells,mediating impaired mitochondrial autophagy,etc.In addition,tacrolimus also raises blood glucose levels through various pathways,such as affecting gut microbiota metabolism and activating bile acid signaling pathways.In recent years,some new anti-diabetic drugs have shown certain application prospects in kidney transplant recipients,but the evidence-based medical evidence for their combined use still needs further exploration.In the future,it is necessary to conduct in-depth research on the multiple sites of action of tacrolimus to reduce the occurrence of PTDM and improve the prognosis of kidney transplant recipients.

The decrease in blood glucose in perinatal dairy cows affects the energy supply and im-mune function of peripheral blood neutrophils(PMN).Fibroblast growth factor 21(FGF21)is an important regulator of glucose metabolism,and serum FGF21 levels in some perinatal cows are significantly elevated after farrowing.In order to explore the effect of FGF21 on PMN glucose ho-meostasis in perinatal dairy cows,the cows were divided into high FGF21 group(high FGF21,n=8,FGF21＞800 ng/L)and low FGF21 group(low FGF21,n=8,FGF21＜200 ng/L)within 3 weeks postpartum.The results showed that compared with the low FGF21 group,the glucose up-take of PMN and the mRNA expression of glucose transporters SLC2A1 and SLC2A3 were signifi-cantly increased in the high FGF21 group.The activities of phosphofructokinase 1(PFK1)and glu-cose-6-phosphate dehydrogenase(G6PDH)were significantly increased,and the activity of glyco-gen synthase(GCS)was significantly decreased in PMN in the high FGF21 group.The lactate con-tent and ATP content of PMN were significantly increased,and the mRNA and protein expressions of hexokinase(HK2)and PFK1 were significantly increased in the high FGF21 group.These re-sults indicated that the uptake and utilization of glucose by PMN in perinatal peripheral blood FGF21 increased to ensure the ATP supply of PMN,which provided a theoretical basis for the pro-posal of a new strategy to alleviate immunosuppression in perinatal dairy cows.

OBJECTIVE To summarize the clinical characteristics and diagnosis and treatment experiences in dealing with non-severe Chlamydia psittaci pneumonia.METHODS The clinical data were collected from 34 patients who were diagnosed with non-severe C.psittaci pneumonia through quantitative polymerase chain reactiong(qPCR)for sputum in fever clinic of the First Medical Center of Chinese PLA General Hospital from Mar.2023 to Mar.2024 and were retrospectively analyzed.The clinical characteristics and treatment outcomes were evaluated.RESULTS The average age of the patients was(44.82±13.74)years old,the ratio of male to female was 1∶1.83;all of the patients had fever;major symptoms were cough(70.59％),pharyngodynia(44.12％),and flu-like symptoms(41.18％);82.35％of the patients had the history of contact with poultry.The C-reactive pro-tein(CRP)level,interleukin-6(IL-6),systemic inflammatory response index(SIRI)and aggregate index of sys-temic inflammation(AISI)were higher among the patients aged no less than 44 years old than among the patients less than 44 years old(P＜0.05);the percentage of lymphocytes of the patients aged no less than 44 years old was lower than that of the patients aged less than 44 years old(P＜0.05).As for the imaging findings,73.53％of the patients had consolidation shadows,26.47％had ground-glass opacities,and 32.35％involved both lungs.All of the patients received quinolones or tetracyclines for treatment of 7-14 days and all symptoms relieved.CT reexami-nated 1 month after the treatment showed that 55.88％of the cases had complete absorption of pulmonary infec-tious lesions,and 35.29％had partial absorption.CONCLUSIONS The patients with non-severe Chlamydia psitta-ci pneumonia are characterized by the history of contact with poultry,fever complicated with respiratory tract symptoms,rise of inflammatory markers(more significant among patients of advanced age)and lower lobe con-solidation shadow/ground-glass opacities.Early identification and standardized treatment may facilitate the favora-ble treatment outcomes.

Hypoxia leads to persistent constriction and remodeling of pulmonary blood vessels,resulting in pulmonary hypertension(PH)and,in severe cases,right heart failure.Endothelial-mesenchymal transition(EndMT)is a biological process in which endothelial cells undergo functional and phenotypic transformation into mesenchymal cells,playing a critical role in pulmonary vascular remodeling.Recent studies have revealed that hypoxia promotes pulmonary vascular EndMT in PH through the mechanisms involving inflammation,transcription factors,signaling pathways,circular RNAs,and microRNAs.This article provides a review of recent research on the mechanisms of hypoxia-induced pulmo-nary vascular EndMT in PH,with the aim of offering insights for inhibiting pulmonary vascular remodeling in PH.

Establishing a culture system throughout the whole cycle of medical education is the key task in cultivating medical talents in the new era.This study adopts a case study approach to examine the"Four-Level,Four-Dimension"cultural education model implemented at Xiangya Medical College.By analyzing the four-level collaborative pathway of"school-hospital-department-individual"and combining with the four dimensions of"culture guidance,practice integration,specialty collaboration and individual development".This paper discusses the role and effectiveness of this model in cultivating medical humanistic liter-acy and inheriting medical spirit and provides"Xiangya experience"for the construction of medical education culture system in the new era.

BackgroundPatients with depressive disorder often exhibit impaired decision-making functions. However， the relationship between decision-making abilities and depressive and anxiety symptoms in these patients remains unclear. ObjectiveTo explore the characteristics of decision-making behavior in patients with depressive disorder， and to analyze its relationship with clinical symptoms. MethodsA total of 48 patients diagnosed with depressive disorder according to the Diagnostic and Statistical Manual of Mental Disorders， fourth edition （DSM-IV） were recruited from the Department of Psychosomatic Medicine of the Affiliated Hospital of Southwest Medical University from October 2020 to May 2023. Concurrently， 52 healthy individuals matched for age and gender were recruited from Luzhou as the control group. Beck Depression Inventory （BDI） and Beck Anxiety Inventory （BAI） were used for assessment， and decision-making behavior was evaluated using Probabilistic Reversal Learning （PRL） task. Indicators assessed included the number of trials to criterion， perseverative errors， win-stay rate and lose-shift rate. Spearman correlation analysis was used to assess the correlation between BDI and BAI scores and PRL task indicators. ResultsThe depression group showed a significantly higher lose-shift rate compared with the control group （t=3.684， P<0.01）. There were no statistically significant differences between two groups in trials to criterion， perseverative errors and win-stay rate （t=0.329， 0.132， 0.609， P>0.05）. In depression group， BDI and BAI scores were positively correlated with the win-stay rate（r=0.450， 0.398， P<0.01）. ConclusionPatients with depressive disorder are more likely to change their decision-making strategies following negative outcomes. Furthermore， the severity of depressive and anxiety symptoms is associated with a greater propensity to maintain existing decisions after receiving positive feedback. ［Funded by 2019 Joint Project of Luzhou Science and Technology Bureau-Southwest Medical University （number， 2019LZXNYDJ39］