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.

Objective To develop a portable three-dimensional foot motion analysis system based on low-cost inertial measurement units(IMU)and force sensing resistor(FSR),and to explore the feasibility of assessing three-dimensional motion of internal small joints of foot in barefoot and shod conditions. Methods The system consisted of data sampling,data transmitting and data processing parts.IMUs were employed for data acquisition of small foot joints,and FSRs were utilized to detect heel strike and toe off.All the data were transmitted via wireless local area network.Data processing was accomplished by a self-programmed Excel mac-ro.From January to July,2024,two healthy female subjects wearing the device walked in the corridor at self-se-lected pace,for ten meters.Gait analysis was used to conduct consistency test on subject 2.Dorsiflexion-plan-tarflexion,adduction-abduction and internal rotation-external rotation of the 1st metatarsal relative to the phalan-geal(Met-Ph),the midfoot relative to the 1st metatarsal(Mid-Met)were recorded and analyzed on subject 1 in consecutive barefoot walking and two types of nurse footwear walking conditions. Results The system showed good consistency between tests.Dorsiflexion-plantarflexion,adduction-abduction and inter-nal rotation-external rotation ranges of motion were reduced in both Met-Ph and Mid-Met with shoes compared with those of bare foot,they were the least in arch support. Conclusion A low-cost,portable three-dimensional foot motion analysis system has been developed,which could be used to measure barefoot motion and shod foot motion in consecutive walking.

Objective:To investigate the clinical efficacy of over-the-top reconstruction combined with the modified Lemaire technique in the treatment of anterior cruciate ligament (ACL) injuries with pivot-shift positive.Methods:From March 2020 to October 2021, a total of 46 patients with ACL injury and pivot-shift test grade II or above were admitted to Xinhua Hospital Affiliated to Dalian University. There were 28 males and 18 females, aged 28.0±10.5 years (range, 15-45 years). All cases were unilateral, including 17 cases of left knee and 29 cases of right knee. The pivot-shift test showed that 30 cases were grade II and 16 cases were grade III, and the cause of injury was sports injury. The semitendinosus muscle and gracilis muscle were harvested, and the ACL was reconstructed with the over-the-top combined modified Lemaire technique. The International Knee Documentation Committee (IKDC) score, Lysholm score and KT-2000 side-to-side difference before and after operation were compared.Results:All patients successfully completed the operation and were followed up for 26.6±2.3 months (range, 24-28 months). The Lysholm scores of the patients at 3 months and 24 months after operation were 73.6±4.3 and 91.6±2.8, which were higher than those before operation (58.5±4.6), and the difference was statistically significant ( F=18.351, P<0.001). The IKDC scores of patients at 3 months and 24 months after operation were 59.0±2.0 and 91.8±3.2, respectively, which were higher than those before operation 50.3±2.8, and the difference was statistically significant ( F=17.290, P<0.001). The side-to-side difference of KT-2000 was 1.7±0.8 mm and 1.5±0.4 mm at 3 and 24 months after operation, respectively, which was lower than that before operation (5.9±1.1 mm), and the difference was statistically significant ( F=14.192, P<0.001). At 24 months after operation, 3 patients had pivot shift test grade I and 4 patients had Lachman test grade I, but they complained of good knee stability and did not receive further treatment. At the last follow-up, there were no complications such as incision and intra-articular infection, deep vein thrombosis, knee stiffness, quadriceps musculus ossificans myositis, and reconstruction ligament rupture. All patients returned to sports with an average time of 15.7±2.6 months (range, 12-24 months). Conclusion:Over-the-top reconstruction combined with the modified Lemaire technique for the treatment of ACL injury with positive pivot shift test effectively improves knee function and promotes the patient's return to sports, with a low incidence of surgical complications.

Objective:To analyze the influence factors on the efficacy of immunosuppression therapy (IST) combined with eltrombopag and IST alone in the treatment of childhood severe aplastic anemia (SAA).Methods:A retrospective cohort study. A total of 124 children with SAA who were initially treated with IST at Beijing Children′s Hospital from March 2017 to May 2020 were enrolled. Clinical characteristics, laboratory examination and prognosis data were collected at the time of enrollment. According to the treatment plan, the children were divided into the eltrombopag combined with IST group (eltrombopag group) and the IST group. Binary Logistic regression model was used to analyze the factors affecting the efficacy of the two groups at 6 months of treatment, and the factors affecting the efficacy of the eltrombopag group at the end of follow-up.Results:There were 75 cases (45 males and 30 females) in the eltrombopag group. The age of diagnosis was 5.9 (3.5, 8.5) years. There were 49 patients in the IST group, including 23 males and 26 females, whose age at diagnosis was 6.2 (4.4, 8.8) years. The absolute lymphocyte count before treatment in the eltrombopag group was significantly lower than that in the IST group (1.1 (0.4, 1.6)×10 9vs. 2.1 (1.4, 2.8)×10 9/L). Absolute reticulocyte count in the eltrombopag group was significantly higher than that of IST group (26.9 (8.7, 54.2)×10 9vs. 9.5 (4.0, 19.0)×10 9/L) (both P<0.05). Influencing factors of 6-month response: a comparison between response and un-response groups in the eltrombopag treated patients showed that, before treatment, hemoglobin (69 (61, 78) vs. 64 (59, 68) g/L), platelet (10 (6, 16)×10 9vs. 6 (3, 8)×10 9/L), absolute reticulocyte count (ARC) (34.0 (15.8, 57.3)×10 9vs. 6.5 (4.6, 16.8)×10 9/L) and the response rate to granulocyte colony stimulating factor (G-CSF) after treatment (82.4% (47/57) vs. 9/18) were significantly different (all P<0.05). Logistic regression model analysis showed that ARC ( OR=1.09, 95% CI 1.02-1.18) and absolute neutrophil count were independent influencing factors of 6-month response rate in the eltrombopag group ( OR=0.00, 95% CI 0.00-0.89). ARC was also the independent influencing factors of the end of follow-up response rate in the eltrombopag group ( OR=1.04, 95% CI 1.01-1.07). Conclusions:Pre-treatment blood count and response to G-CSF were predictors of overall response to eltrombopag combined with IST. The higher the ARC before treatment, the higher the total response rate and complete response.

Objective To establish and validate a predictive model for acute posterior circulation infarction in patients with vertebral artery dysplasia based on ultrasound and clinical data.Methods A total of 347 patients with an ultrasonic diagnosis of vertebral artery dysplasia who were admitted to our hospital from March 2017 to December 2023 were enrolled as subjects.A multivariate logistic regression analysis was used to identify the risk factors for acute posterior circulation infarction in patients with vertebral artery dysplasia,and R software was used to establish a nomogram predictive model for acute posterior circulation infarction in patients with vertebral artery dysplasia.Then the model was assessed and validated.Results Among the 347 patients with vertebral artery dysplasia,50 patients developed acute posterior circulation infarction,resulting in an incidence rate of 14.4%.The multivariate logical regression analysis showed that the nomogram model based on the predictive factors of hypertension,diabetes,hyperhomocysteinemia,embryonal posterior cerebral artery,and vertebral artery dominance had an area under the ROC curve of 0.772(95%confidence interval:0.700?0.844),with a Brier score of 0.105.Conclusion The nomogram model based on the predictive factors of hypertension,diabetes,hyperhomocysteinemia,embryonal posterior cerebral artery,and vertebral artery dominance has a relatively high value in predicting acute posterior circulation infarction in patients with vertebral artery dysplasia.

Objective To investigate whether norepinephrine (NE) regulates the oxidative stress in human endom-etrial epithelial cells (hEECs) by activating nuclear factor E2-related factor 2(Nrf2)/ heme oxygenase -1(HO-1) signal pathway.Methods Cultured hEECs were used.The expression of α and β adrenergic receptors was detec-ted by reverse transcription-polymerase chain reaction (RT-PCR).Cell counting kit-8(CCK-8) assay was applied to test the effect of NE on cell viability, then the cells were divided into Control group and NE treatment group, and the appropriate concentrations were chosen.The expression of tight junction proteins Occludin and zona occludens-1(ZO-1), apoptosis-related proteins apoptosis-related protein B-cell lymphoma-2 protein(Bcl-2) and Bcl-2 associ-ated X protein(Bax) , antioxidant proteins Nrf2 and HO-1 were examined by Western blot.The apoptosis was de-tected by flow cytometry.The malonaldehyde (MDA) and superoxide dismutase(SOD) in the cell culture medium were detected by enzyme-linked immunosorbent assays kit (ELISA).Results The mRNA expression of α1 a,α1 b,α2 a,α2 b,α2 c,β1, β3 was detected in the hEECs.After the NE treatment, no significant change in cell viability was observed in low concentration (5 μmol/L and 10 μmol/L) groups, while 15 μmol/L and 20μmol/L NE treatments for 6 h or 24 h promoted the cell viability significantly.The expression of ZO-1 and Occlu-din increased significantly in 15 μmol/L group after 24 h treatment, the expression of ZO-1 decreased in 6 h treat-ment group, significant down regulation was observed after 15 μmol/L NE application, the expression of Occludin increased in 6 h group.The cell apoptosis increased compared with the control group after NE stimulation, espe-cially a significantly increase in 6 h 15 μmol/L group was detected,while the fall in increased apoptosis was ob-served after 24 h treatment.The ration of Bcl-2/Bax>1.The expression of Nrf2 and HO-1 was elevated by NE.There was no obvious change in MDA level while significant elevation in SOD was detected in cell culture medium.Conclusion Nrf2/HO-1 signal is activated after application of NE to the hEECs, which may responsible for the upregulation of SOD, antioxidant and anti-apoptotic effect in the hEECs.

In multiple areas such as science, technology, and economic activities, it is necessary to unify the management of repetitive tasks or concepts by standardization to obtain the best order and high efficiency. Organoids, as living tissue models, have rapidly developed in the past decade. Organoids can be used repetitively for in vitro culture, cryopreservation, and recovery for further utilization. Because organoids can recapitulate the parental tissues' morphological phenotypes, cell functions, biological behaviors, and genomic profiles, they are known as renewable "living biobanks". Organoids cover two mainstream fields: Adult stem cell-derived organoids (also known as patient-derived organoids) and induced pluripotent stem cell-derived and/or embryonic stem cell-derived organoids. Given the increasing importance of organoids in the development of new drugs, standardized operation, and management in all steps of organoid construction is an important guarantee to ensure the high quality of products. In this review, we systematically introduce the standardization of organoid construction operation procedures, the standardization of laboratory construction, and available standardization documents related to organoid culture that have been published so far. We also proposed the challenges and prospects in this field.
Organoids ; Humans ; Biological Specimen Banks/standards* ; Induced Pluripotent Stem Cells/cytology* ; Cryopreservation/methods*

Objective:To investigate the efficacy of shoulder arthroscopic balance point compaction with cross suture-bridge technique inr the treatment of avulsion fracture of the greater tuberosity of the humerus.Methods:A retrospective case series study was conducted on 14 patients with avulsion fracture of the greater tuberosity of the humerus treated in Affiliated Xinhua Hospital of Dalian University from March 2021 to March 2022, including 8 males and 6 females; aged 30-58 years [(40.2±10.5)years]. Among them, 5 patients had fracture in the left shoulder and 9 in the right shoulder. The fracture was classified as the avulsion type according to Mutch classification. All the patients were treated with shoulder arthroscopic balance point compaction with cross suture-bridge technique. The anteroposterior X-ray of the shoulder joint was taken at 1 week, 3 months, and 6 months after surgery to evaluate fracture reduction and fixation. The operative time and intraoperative blood loss were recorded. Fracture healing was evaluated by shoulder MRI at 6 months after surgery. The visual analog score (VAS), Constant shoulder joint score, American Shoulder and Elbow Surgeons (ASES) score, and shoulder range of motion (active abduction angle, active lateral external rotation angle, and active lateral internal rotation) preoperatively, at 3, 6 months after surgery and at the last follow-up were compared. The postoperative complications were observed.Results:All the patients were followed up for 12-15 months [(12.5±0.8)months]. The operative time and intraoperative blood loss were (67.0±10.5)minutes and (20.0±3.8)ml. The anteroposterior X-ray of the shoulder joint showed good reduction and fixation at 1 week, 3 months and 6 months after surgery. MRI T1 image at 6 months after surgery showed locally evenly distributed high signal, suggesting that the fracture was healed well. The values of VAS were (3.2±0.4)points, (2.5±0.5)points, and (0.7±0.3)points at 3, 6 months after surgery and at the last follow-up, which were lower than (7.2±0.6)points preoperatively; the values of Constant joint shoulder score were (53.2±5.3)points, (81.1±4.4)points, and (92.8±5.3)points, which were higher than (42.3±7.6)points preoperatively; the values of ASES score were (55.6±3.6)points, (77.1±3.2)points, and (90.8±3.5)points, which were higher than (45.8±4.2)points preoperatively; the active abduction angles were (60.5±2.5)°, (107.8±6.6)°, and (168.5±3.5)°, which were higher than (18.3±3.3)°preoperatively; the active lateral external rotation angles were (25.8±2.5)°, (30.8±2.2)°, and (63.8±2.8)°, which were higher than (15.6±3.2)°preoperatively ( P<0.05 or 0.01). The level of active internal rotation was L 5, L 1, and T 10, which was better than S 3 before surgery. The VAS, Constant shoulder joint score, ASES score, active abduction and active external rotation were significantly improved at the last follow-up compared with those at 3, 6 months after surgery (all P<0.05), with markedly improved level of active internal rotation. No major complications such as infection, instability of the shoulder joint or acromial impingement were found after surgery. Conclusion:Shoulder arthroscopic balance point compaction with cross suture-bridge technique for the treatment of avulsion fracture of the greater tuberosity of the humerus has advantages of decreased intraoperative blood loss, good reduction and healing, shoulder pain relief, early restoration of shoulder function and mobility, and few complications.

Objective: To investigate fast food consumption behaviors among 4th and 5th grade primary school students in agricultural and pastoral areas in Qinghai Province, and to provide scientific basis for nutrition education and intervention measures for school age children in agricultural and pastoral areas. Methods: Using multi stage stratified cluster random sampling method, a total of 969 fourth and fifth grade students were selected from 10 primary schools in 4 counties and districts in 3 cities of Haidong City, Hainan Prefecture and Haixi Prefecture from Qinghai Province. Self administered questionnaires were used to investigate the fast food consumption behaviors of participants. Results: The proportions of senior primary school students in agricultural and pastoral areas of Qinghai Province who had consumed western fast food and traditioal fast food in the past week were 45.8% and 75.6%, respectively, with statistically significant differences ( χ 2=290.24, P <0.05). The times of traditional fast food consumption in the past week among boarding students were higher than that of non boarding students( Z =6.44,5.84, P <0.05). The main reasons for senior primary school students in agricultural and pastoral areas of Qinghai Province to choose to consume western fast food were that it was delicious (84.7%), nutritious (62.6%), clean and hygienic (57.4%), and a better environment (57.0%). The top 4 reasons for chousing Chinese fast food were yummy(83.8%),nutritious(82.8%),clean and healthy(67.4%),and good environment(53.5%). Among the surveyed primary school students, 64.7% believed that diet structure of Chinese fast food was reasonable, 43.0% believed that the nutritional value of Chinese fast food was high, and 39.4% believed that the energy content of western fast food was high. Conclusion Fast food consumption is a common dietary behavior of senior primary school students in agricultural and pastoral areas of Qinghai Province. Relevant departments should strengthen the nutrition education related to fast food, promote the dissemination of health knowledge, enable students to develop a good lifestyle and reduce fast food consumption.

Objective: To study the consumption of beverages among senior primary school students in rural and pastoral areas of Qinghai Province, China, in order to provide evidence for the development of nutrition and intervention strategies. Methods: A multi stage stratified cluster random sampling method was employed to select 969 primary school students in grades 4 and 5 from 10 schools in Hainan Autonomous Prefecture, Haixi Autonomous Prefecture and Haidong City. All participants completed a questionnaire survey on daily beverage consumption. The Chi square test was performed to compare differences in reported rates of beverage consumption among students in different groups. Results: The proportion of students who consumed beverages at home, school and elsewhere were 96.9%, 64.5% and 84.9%, respectively. The most popular beverages consumed at home were milk and yogurt ( 63.1 %), tea water (53.0%), and tea drinks (52.4%). The most popular beverages consumed at school were tea(29.8%), milk and yogurt (27.8%) and tea drinks (18.4%), while the most popular beverages consumed in other places were tea drinks ( 42.0 %), carbonated drinks (38.1%) and milk and yogurt (35.0%). The top five reasons for choosing a given beverage were taste delicious (81.2%), nutritious (57.6%),healthy and clean(52.6%),many students like to drink(39.6%),family members often drink(37.7%). Conclusion The consumption of beverages was popular among students, and sugared beverages represented a large proportion of the beverages consumed. Therefore, there is an urgent need to improve the food environment and provide effective nutrition education for students, so as to encourage the consumption of healthy beverages and cultivate healthy eating behaviors.