Collagen is a major structural protein in the matrix of animal cells and the most widely distributed and abundant functional protein in mammals. Collagen’s good biocompatibility, biodegradability and biological activity make it a very valuable biomaterial. According to the source of collagen, it can be broadly categorized into two types: one is animal collagen; the other is recombinant collagen. Animal collagen is mainly extracted and purified from animal connective tissues by chemical methods, such as acid, alkali and enzyme methods, etc. Recombinant collagen refers to collagen produced by gene splicing technology, where the amino acid sequence is first designed and improved according to one’s own needs, and the gene sequence of improved recombinant collagen is highly consistent with that of human beings, and then the designed gene sequence is cloned into the appropriate vector, and then transferred to the appropriate expression vector. The designed gene sequence is cloned into a suitable vector, and then transferred to a suitable expression system for full expression, and finally the target protein is obtained by extraction and purification technology. Recombinant collagen has excellent histocompatibility and water solubility, can be directly absorbed by the human body and participate in the construction of collagen, remodeling of the extracellular matrix, cell growth, wound healing and site filling, etc., which has demonstrated significant effects, and has become the focus of the development of modern biomedical materials. This paper firstly elaborates the structure, type, and tissue distribution of human collagen, as well as the associated genetic diseases of different types of collagen, then introduces the specific process of producing animal source collagen and recombinant collagen, explains the advantages of recombinant collagen production method, and then introduces the various systems of expressing recombinant collagen, as well as their advantages and disadvantages, and finally briefly introduces the application of animal collagen, focusing on the use of animal collagen in the development of biopharmaceutical materials. In terms of application, it focuses on the use of animal disease models exploring the application effects of recombinant collagen in wound hemostasis, wound repair, corneal therapy, female pelvic floor dysfunction (FPFD), vaginal atrophy (VA) and vaginal dryness, thin endometritis (TE), chronic endometritis (CE), bone tissue regeneration in vivo, cardiovascular diseases, breast cancer (BC) and anti-aging. The mechanism of action of recombinant collagen in the treatment of FPFD and CE was introduced, and the clinical application and curative effect of recombinant collagen in skin burn, skin wound, dermatitis, acne and menopausal urogenital syndrome (GSM) were summarized. From the exploratory studies and clinical applications, it is evident that recombinant collagen has demonstrated surprising effects in the treatment of all types of diseases, such as reducing inflammation, promoting cell proliferation, migration and adhesion, increasing collagen deposition, and remodeling the extracellular matrix. At the end of the review, the challenges faced by recombinant collagen are summarized: to develop new recombinant collagen types and dosage forms, to explore the mechanism of action of recombinant collagen, and to provide an outlook for the future development and application of recombinant collagen.

Objective:To observe the inhibitory effect of dobutamine on proliferation of FLT3-ITD mutated acute myeloid leukemia(AML)cells and explore the feasibility of dobutamine as a monotherapy or in combination with quizartinib for the treatment of this type of AML.Methods:FLT3-ITD mutant cell lines MOLM13 and MV4-11 were cultured in vitro and divided into control group,dobutamine treatment group,quizartinib treatment group,and dobutamine combined with quizartinib treatment group.Cell viability,ROS levels,and apoptosis rate were detected by CCK-8,Flow cytometry,respectively,as well as the expression of YAP1 protein by Western blot.Results:Both dobutamine and quizartinib inhibited the proliferation of FLT3-ITD mutant AML cell lines.Compared with the control group,the dobutamine group exhibited a significant increase in ROS levels(P＜0.01),an increase in apoptosis rates(P＜0.05),and a decrease in YAP1 protein expression(P＜0.05).Compared with the dobutamine group,the combination of quizartinib and dobutamine significantly reduced cell viability(P＜0.05),increased ROS levels(P＜0.01),and decreased YAP1 expression(P＜0.05).Conclusion:Dobutamine as a monotherapy can inhibit the proliferation of FLT3-ITD mutated AML cells,inducing apoptosis.Additionally,the combination of quizartinib enhances the targeted inhibitory effect on FLT3-ITD mutated AML.The mechanism may involve the inhibition of YAP1 protein expression in AML cells of this type,leading to an increase in ROS levels and exerting its anti-tumor effects.

Objective:The purpose of this study is to explore in depth the mechanism of the impact of brain drain on organizational cohesion,with a view to cracking the vicious circle problem caused by brain drain in the northeast region and eliminating the unfavorable factors affecting the core cohesion of public health institutions.Methods:A combination of convenience sampling and snowball sampling was used to survey11 912 valid questionnaires,and the data were systematically analyzed using descriptive statistics,regression analysis,and moderated mediated effects analysis.Results:Brain drain has a significant negative effect on organizational cohesion(β=-1.29,P<0.001);and role overload partially mediates between the two,with a significant mediating effect(effect value=-0.56,95%CI=-0.67～-0.46),and the indirect effect accounts for 43.4%of the total effect;and monthly income significantly moderates the effect of brain drain on organizational cohesion through role overload(β=1.00,P<0.001).Conclusion:It is recommended to alleviate the sense of role overload among public health personnel by adjusting the level of salary and benefits,and to reduce the negative impact of brain drain by adopting long-term incentive mechanisms and other strategies,thus enhancing organizational cohesion and providing theoretical and practical guidance for relevant institutions.

Objective:To investigate the safety and clinical effect of testis-sparing microsurgery(TSMS)in the treatment of benign testis tumor(BTT).Methods:We retrospectively analyzed the clinical data on 16 cases of BTT treated in the Department of Andrology of the Affiliated Hospital of Qingdao University from October 2020 to February 2023.The median age of the patients was 23 years.All the tumors were unilateral,7 in the left and 9 in the right side,with a median diameter of 1.85 cm(1.0-3.5 cm).The patients all underwent color Doppler flow imaging(CDFI),MRI,semen analysis and examination of serum T,alpha-fetoprotein(AFP),human chorionic gonadotropin(HCG)and lactate dehydrogenase(LDH),followed by TSMS.The boundaries between the tumors and normal testis tissue were accurately identified under the microscope,and the tumors and the adjacent normal testis tissue 2 mm from their margins were excised completely.Bipolar coagulation forceps were used for wound hemostasis to maximally preserve the normal testis tissue.The resected specimens were subjected to fast frozen pathology intraoperatively,and the patients were followed up for 14-40 months by regular scrotal CDFI,MRI and examinations of serum T and semen parameters.Results:The levels of serum T,AFP,HCG and LDH and semen parameters were all within the normal range preoperatively.TSMS were successfully completed in all the cases,and all were pathologically confirmed as BTT according to the latest edition of WHO Classification of Tumors:Urinary and Male Genital Tumors.CDFI showed normal blood supply within the testis tissue at 1 month after surgery.No signs of intra-testicu-lar tumor residue,recurrence or metastasis,nor significant changes in the levels of serum T,AFP,HCG or LDH or semen parameters were observed during the follow-up as compared with the baseline.Natural conception was achieved in 2 cases at 16 and 18 months re-spectively after surgery.Conclusion:BTT can be differentially diagnosed by CDFI and MRI before surgery and confirmed by histo-pathology.TSMS can achieve complete excision of the tumor,maximal sparing of the normal testis tissue and thereby effective preserva-tion of male fertility.

Objective To investigate the association between auditory processing and problem behaviors in preschool children,as well as the mediating role of executive function.Methods A total of 2 342 preschool children were selected from 7 kindergartens in Nanjing,China from June to August 2021.They were evaluated using Preschool Auditory Processing Assessment Scale,Conners Parent Symptom Questionnaire,and Behavior Rating Inventory of Executive Functioning-Preschool version.Children with different demographic features were compared in the scores and the abnormality rates of auditory processing,problem behaviors,and executive function.The influencing factors of the total scores of auditory processing,problem behaviors,and executive function were evaluated using multiple linear regression analysis.Whether executive function was a mediating factor between auditory processing and executive function was examined.Results Sex and grade were the main influencing factors for the total score of auditory processing(P<0.05),and sex,grade,parental education level,and family economic status were the main influencing factors for the total scores of problem behaviors and executive function(P<0.05).The auditory processing score(rs= 0.458,P<0.05)and problem behavior score(rs=0.185,P<0.05)were significantly positively correlated with the executive function score,and the auditory processing score was significantly positively correlated with the problem behavior score(rs=0.423,P<0.05).Executive function played a partial mediating role between auditory processing and problem behaviors,and the mediating effect accounted for 33.44% of the total effect.Conclusions Auditory processing can directly affect the problem behaviors of preschool children and indirectly affect problem behaviors through executive function.[Chinese Journal of Contemporary Pediatrics,2024,26(2):174-180]

Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.

Objective To investigate the risk factors for bronchopulmonary dysplasia(BPD)in twin preterm infants with a gestational age of<34 weeks,and to provide a basis for early identification of BPD in twin preterm infants in clinical practice.Methods A retrospective analysis was performed for the twin preterm infants with a gestational age of<34 weeks who were admitted to 22 hospitals nationwide from January 2018 to December 2020.According to their conditions,they were divided into group A(both twins had BPD),group B(only one twin had BPD),and group C(neither twin had BPD).The risk factors for BPD in twin preterm infants were analyzed.Further analysis was conducted on group B to investigate the postnatal risk factors for BPD within twins.Results A total of 904 pairs of twins with a gestational age of<34 weeks were included in this study.The multivariate logistic regression analysis showed that compared with group C,birth weight discordance of>25%between the twins was an independent risk factor for BPD in one of the twins(OR=3.370,95%CI:1.500-7.568,P<0.05),and high gestational age at birth was a protective factor against BPD(P<0.05).The conditional logistic regression analysis of group B showed that small-for-gestational-age(SGA)birth was an independent risk factor for BPD in individual twins(OR=5.017,95%CI:1.040-24.190,P<0.05).Conclusions The development of BPD in twin preterm infants is associated with gestational age,birth weight discordance between the twins,and SGA birth.

Objective:To explore the best practices for the management of hospital medical consumables quantity-based procurement under the policy of quantity-based procurement for orthopedic medical consumables,and to promote the implementation of quantity-based procurement of orthopedic medical consumables.Methods:The relevant policies on quantity-based procurement of orthopedic medical consumables in recent years in China were sorted out,and the characteristics and management requirements of the policies were analyzed.The difficulties encountered by medical institutions in the practical process of quantity-based procurement of medical consumables in terms of procurement model,usage supervision and supply chain management were analyzed.A multi-departmental management collaboration model was established based on the two-tier management structure consisting of orthopedic clinical expert teams and quantity-based procurement medical consumable management teams of Peking Union Medical College Hospital,and a dynamic monitoring platform for medical consumables procurement data was built using information technology.The implementation of quantity-based procurement of orthopedic medical consumables for knee and hip joints in the implementation cycle of orthopedic medical consumables procurement based on the two-tier management structure of the hospital from 2022 to 2023 was evaluated.Results:In the execution cycle of quantity-based procurement based on the two-tier management structure,the completion of the quantity-based procurement medical consumables agreement could be monitored in real time.The agreement volume statistics time had been shortened from the original one week to real-time statistics,saving 83.6%of the medical consumables cost throughout the year.Conclusion:The quantity-based procurement management model for orthopedic medical consumables based on a two-tier management structure can strengthen the information monitoring means of medical consumables,improve the completion rate of quantity-based procurement agreements for orthopedic medical consumables,and promote the smooth and orderly implementation of quantity-based procurement of orthopedic medical consumables by building a dynamic monitoring platform for quantity-based procurement data for medical consumables.

Objective:To explore the hot spots and development direction of medical consumables research in China,and to provide reference for further improving the management of medical consumables and the quality of medical services.Methods:The academic journals with medical consumables as the subject word were searched in the database of China National Knowledge Network(CNKI)from 1 January 2014 to 20 December 2023.A total of 2,656 related literatures were retrieved,and 1,865 research literatures were finally included according to the inclusion and exclusion criteria.CiteSpace literature analysis software was used to analyze the number of publications,research institutions,high-frequency keywords and keyword emergence of 1,865 selected literatures.Results:The overall number of publications in the field of medical consumables in China showed an overall upward trend from 2014 to 2023,and the relevant literature research reached a peak from 2019 to 2022,with the annual publication volume maintained at around 250.The topics related to informatization,cost control,rational use,and volume-based procurement of medical consumables were the focus of attention.Conclusion:It is necessary to continue to explore the cost control of medical consumables,especially low-value non-chargeable consumables,and be good at using scientific methods such as health technology evaluation to build an evaluation system for rational use of medical consumables.The research on volume-based procurement has been a hot topic recently,and may continue to lead the research trend in the future,and the supervision of the use of volume-based procurement is the top priority of subsequent medical consumables management and research.

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.