Objective To investigate the influence of different cell structures on the static and dynamic mechanical performance of porous titanium alloy scaffolds,and to provide a theoretical mechanical basis for the application of scaffolds in the repair of mandibular bone defects.Methods Porous titanium alloy scaffolds with diamond,cubic,and cross-sectional cubic cell structures were manufactured using three-dimensional printing technology.Uniaxial compression tests and ratcheting fatigue with compression load tests were conducted to analyze the static and dynamic mechanical performances of scaffolds with different cell structures.Results The elastic moduli of the diamond cell,cross-sectional cubic cell,and cubic cell scaffolds were 1.17,0.566,and 0.322 GPa,respectively,and the yield strengths were 71.8,65.1,and 31.8 MPa,respectively.After reaching the stable stage,the ratcheting strains of the cross-sectional cubic,diamond,and cubic cell scaffolds were 3.3%,4.0%,and 4.5%,respectively.The ratcheting strain increased with increasing average stress,stress amplitude,and peak holding time,and decreased with increasing loading rate.Conclusions The evaluation results of the static mechanical performance showed that the diamond cell scaffold was the best,followed by the cross-sectional cubic cell scaffold and the cubic cell scaffold.The evaluation results of the dynamic mechanical performance showed that the cross-sectional cubic cell scaffold performed the best,followed by the diamond cell scaffold,whereas the cubic cell scaffold performed the worst.The fatigue performance of the scaffold is affected by the loading conditions.These results provide new insights for scaffold construction for the repair of mandibular bone defects and provide an experimental basis for further clinical applications of this scaffold technology.

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.

During coronavirus disease 2019 epidemic, the treatment of severe trauma has been impacted. The Consensus on emergency surgery and infection prevention and control for severe trauma patients with 2019 novel corona virus pneumonia was published online on February 12, 2020, providing a strong guidance for the emergency treatment of severe trauma and the self-protection of medical staffs in the early stage of the epidemic. With the Joint Prevention and Control Mechanism of the State Council renaming "novel coronavirus pneumonia" to "novel coronavirus infection" and the infection being managed with measures against class B infectious diseases since January 8, 2023, the consensus published in 2020 is no longer applicable to the emergency treatment of severe trauma in the new stage of epidemic prevention and control. In this context, led by the Chinese Traumatology Association, Chinese Trauma Surgeon Association, Trauma Medicine Branch of Chinese International Exchange and Promotive Association for Medical and Health Care, and Editorial Board of Chinese Journal of Traumatology, the Chinese expert consensus on emergency surgery for severe trauma and infection prevention during coronavirus disease 2019 epidemic ( version 2023) is formulated to ensure the effectiveness and safety in the treatment of severe trauma in the new stage. Based on the policy of the Joint Prevention and Control Mechanism of the State Council and by using evidence-based medical evidence as well as Delphi expert consultation and voting, 16 recommendations are put forward from the four aspects of the related definitions, infection prevention, preoperative assessment and preparation, emergency operation and postoperative management, hoping to provide a reference for severe trauma care in the new stage of the epidemic prevention and control.

Objective:To explore the risk factors for urinary tract infection (UTI) after a spinal cord injury (SCI).Methods:The medical records of 403 SCI patients were analyzed retrospectively. They were divided into UTI group and no-UTI group according to whether they had a UTI at admission. Gender, age, cause of injury, injury level of the spinal cord, voluntary anal contraction, time from injury to admission, American Spinal Injury Association (ASIA) grade, axillary temperature at admission, complications at admission (diabetes, hypertension, fracture of the pelvis, pressure sores or anemia), white blood cell count and urinary bacteria were compared between the two groups. Binary logistic regression was used to highlight the risk factors for a UTI after an SCI.Results:Of the 354 patients included in the final analysis, 62 (17.51%) had a UTI at admission. The regression showed that UTI after an SCI was closely related to an inability to voluntarily contract the anus, anemia, elevated white blood cell count and a high level of bacteria in the urine.Conclusions:Inability to contract the anus, fever, anemia and an elevated white blood cell count are independent indicators of a UTI after an SCI. A temperature ≥37.3°C is a simple indicator of a concentration of bacteria in the urine ≥1266/μL.

Abstract: To analyze the changes of intestinal flora and explore the possible mechanisms of alcoholic liver injury in mice. Methods: Six-week-old mice were randomly divided into control group(Ctrl group) and alcohol group(EtOH group). The EtOH group was fed with Lieber-DeCarli liquid feed for 11 days and then given a single alcohol gavage to establish a chronic and acute alcoholic liver injury model. The Ctrl group was fed with liquid control diet and given isocaloric dextrin by gavage. Serum, liver, intestinal tissue and fecal samples were collected 9 h after gavage. The levels of alanine aminotransferase(ALT), aspartate aminotransferase(AST) and triglyceride(TG) in serum and hepatic tumor necrosis factor(TNF)-α, interleukin(IL)-6, IL-8, IL-1β mRNAs were measured. The pathological changes of liver and intestine were observed by HE staining. Illumina highthroughput sequencing was used to detect α diversity, β diversity and species composition at phylum and genus levels. Results: Compared with the Ctrl group, alcohol exposure significantly increased serum ALT and AST in mice(P<0.01), and obviously increased liver IL-6, IL-8 and IL-1β mRNA(P<0.01). HE staining showed that there were scattered cell necrosis and inflammatory infiltration in the liver of mice in EtOH group. The intestinal structure was not clear, the gland was atrophy, and there was obvious inflammatory infiltration. The structure of intestinal flora in EtOH group changed,Firmicutesabundance increased at phylum level(P<0.05),Parasutterella abundance decreased at genus level(P<0.05), andClostridiaceaeandClostridium-sensu-strictowere the key genera. Conclusion The composition of intestinal microflora in mice with alcoholic liver injury changes, which may be related to the occurrence of liver disease.

Crohn's disease (CD) is a chronic nonspecific intestinal inflammatory disease with unclear etiology and pathogenesis. At present, it is believed that CD can cause different degrees of metabolic abnormalities, and that the related metabolites also play an important role in the development and progression of the disease. In recent years, metabonomics is becoming more and more well-developed and has provided guidance for clinicians on rational nutritional support. Here is a review on the metabolic changes of multiple systems in CD patients, the application of metabonomics in CD diagnosis and treatment, and the research progress of clinical nutrition intervention.

Objective To assess the quality of life, prevalence of depression and their influencing factors in patients with alopecia, to investigate, and to provide evidences for relevant clinical therapeutic strategies to improve patients′ quality of life. Methods A questionnaire survey was carried out in 237 patients with androgenetic alopecia or alopecia areata, and their quality of life and depression were measured using dermatology life quality index(DLQI)and center for epidemiologic studies depression scale (CES-D), respectively. Factors influencing the quality of life and depression were analyzed by analysis of variance and logistic regression analysis. Results Among 237 patients with alopecia, 218 questionnaires were eligible with the mean score of DLQI being 9.1 ± 5.4. Alopecia had a moderate effect on the quality of life in general, and 38.07%of the patients were severely affected. The mean score of CES-D was 14.8 ± 9.9, and 37.61%of the patients showed depressive tendency. The DLQI score was positively correlated with CES-D score(r=0.29, P<0.01). One-way analysis of variance(ANOVA)showed that the DLQI score was not affected by age, gender, education level or the number of visits. Multivariate logistic regression analysis revealed that the risk factors for depressive tendency in patients with alopecia were the number of visits (OR = 1.81, 95% CI: 1.21- 2.69) and DLQI score (OR = 1.08, 95% CI: 1.03- 1.13). Conclusion Alopecia not only affects the quality of life, but also mental states of patients.

BACKGROUND:Joint immobilization is one of the methods used to treat joint pain and joint injury in the department of orthopedics. Compared with other treatment methods, immobilization can reduce the pain of the damaged synovial joints and avoid the contact stress and friction between the joints. However, immobilization can cause some serious complications such as joint contracture, osteoporosis and cartilage degeneration.
OBJECTIVE:To observe the effects of joint immobilization on the repair of cartilage injury of knee joint in rats.
METHODS:Osteochondral ful-thickness defects (2.5 mm in diameter;2 mm in depth) were created in the left femoral condyle fossa with a corneal trephine. 36 animals were randomly assigned into immobilization group and control group (n=18 per group). In the control group, animal models were established, without any treatment. In the immobilization group, after model establishment, rats were immobilized by a designed and modified simplified miniature Ilizarov fixator.
RESULTS AND CONCLUSION:(1) Repair rate of cartilage defect:No significant difference in repair rate was detected between immobilization group and control group. (2) Histological staining:Regeneration tissue was mainly fiber cel s in both groups. At 8 weeks after surgery, Wakitani score and Mankin score were higher in the immobilization group than in the control group (P<0.05). (3) Cartilage metabolic marker detection:Compared with the control group, at 8 weeks, C-telopeptide of type II col agen levels in the urine were significantly higher in the immobilization group than in the control group (P<0.05). (4) Results indicated that persistent immobilization could result in cartilage degeneration, and it was detrimental for cartilage repair.

Objective To investigate the chondrocyte proliferation and extracellular matrix biosynthesis of electrospun PCL scaffolds seeded with rabbit chondrocytes under flow perfusion culture in vitro.Methods Nonwoven PCL microfiber mats were fabricated,and contra-aperture cylindrical glass equipment as a perfusion bioreactor was designed and manufactured on our own.The experiment included peffusion culture group and static culture group.Primary chondrocytes were isolated from the knee joints of two-month-old New Zealand white rabbits and seeded into scaffolds.The scaffold-cell complexes were harvested at 3,7,and 14 days of culture for scanning electron micrograph (SEM) analysis,biochemical assay,real-time PCR and histology analysis.Results Electrospun PCL scaffolds were composed of microfibers with a diameter of 1.67±0.76 μm and pores with a diameter of 17.65±7.11 μm.SEM showed a better cell proliferation with typical morphology of chondrocytes under perfusion culture.At 7 days of culture,DNA content in perfusion culture group was higher than in static culture group.At 3,7 and 14 days of culture,compared with the static culture group,glycosaminoglycan (GAG) content and GAG/DNA ratio in perfusion culture group were higher,and the differences were statistically significant.At 14 days of culture,real-time PCR showed aggrecan and collagen type Ⅱ gene expression and collagen type Ⅱ to collagen type Ⅰ ratio were higher in perfusion culture group than in static culture group; HE and safranin O staining showed a significant cell proliferation,infiltration,as well as extracellular matrix biosynthesis in perfusion culture group.Conclusion Under flow perfusion culture,the electrospun PCL scaffolds seeded with rabbit chondrocytes can enhance chondrocyte proliferation and extracellular matrix biosynthesis,which is a promising method for cartilage tissue engineering.

A rare case of anaplastic lymphoma kinase(ALK)-negative anaplastic large cell lymphoma (ALCL)with generalized cutaneous involvement is reported in a 37-year-old man.Seven months prior to the presentation,he developed a goose egg-sized mass in his right thigh without obvious triggers,which gradually grew and no significant discomfort was felt.Diffuse and nonpitting edema gradually appeared in his right thigh and hip.Two months prior to the presentation,multiple dark red papules,nodules,and plaques emerged over the body surface with erosions and ulcers of varying size arising on some of the plaques.Laboratory examination revealed reduced albumin and significantly elevated lactate dehydrogenase in serum.B-mode sonography showed swelling and mutual fusion of superficial lymph nodes,and color Doppler flow imaging revealed markedly increased branch blood flow signals in lymph nodes.Computed tomography(CT)displayed generalized swelling of lymph nodes associated with soft-tissue edema in the right thigh and perineal region,as well as extensive enlargement of epigastric and mediastinal lymph nodes.Pathological examination of the skin lesion revealed a dense dermal infiltrate with mononuclear cells,some of which presented with cellular atypia and atypical nuclear division.Immunohistochemistry of the skin lesion showed that the mononuclear cells stained positive for CD3,CD8,CD30(80％ positive),CD4,CD45RO and granzyme B,but negative for CD56,ALK and T cell intracellular antigen-1(TIA-1).Pathology of lymph nodes indicated that the lymph node structure was completely destroyed with a diffuse growth of tumor cells,which were larger than common large cell lymphoma cells,and contained basophilic or bi-color abundant cytoplasm,deviating,horseshoe-,kidney-shaped,or lobulated cell nuclei,sparse nuclear chromatin and single or multiple small basophilic nucleoli.Angiogenesis,stromal fibrosis and infiltration of varying number of plasma cells and lymphocytes were seen in pathological lymphoid tissue.Immunohistochemistry of lymph nodes showed that the tumor cells stained positive for CD2,CD4,CD3,granzyme B,epithelial membrane antigen(EMA),Ki-67 and CD30,but negative for CD8,CD56,TIA-1 and ALK.The patient was diagnosed with ALK-negative primary systemic ALCL with extensive cutaneous involvement.