In order to separate chiral D-phenylalanine from L-phenylalanine,the enzyme catalytic method by papain and immobilized papain were used in this investigation.It indicated that the yield rate of N-acetyl-DL-phenylalanine synthesized from DL-phenylalanine was 88.7%.The ionic strength was the strongest influencing factor in the synthesis of N-acetyl-L-phenylalanylaniline by both papain and immobilized papain on sodium alginate-ehitosan(IPSAC).But the reaction temperature was the strongest influencing factor in the synthesis by immobilized papain on nylon cloth(IPN).The ionic strength and the pH were the important influencing factors in the synthesis.The yield rates of the best synthesis system of N-acetyl-L-phenylalanylaniline by papain,IPSAC,IPN were 61.2%,54.7%,36.3%,respectively.The yield rate of L-phenylalanine from N-acetyl-L-phenylalanylaniline hydrolyzation was 59.2%.The optical purity of the product was 96.6%.The vield rate of D-phenylalanine from N-acetyl-D-phenylalanine hydrolyzation was 61.7%.The optical purity was 95.7%.

Objective To evaluate the ultrasonic feature and clinical significance of persistent left superior vena cava(PLSVC)in fetal life.Methods Fetal echocardiography was performed in 3368 fetuses.Thirty-one fetuses of PLSVC were confirmed.Results The dilated coronary sinus was observed in 30 of 31 fetuses.Congenital heart defects were presented in 14 of these cases,and extracardiac anomalies were presented in 6 fetuses.Both congenital heart defects and extracardiac anomalies were observed in 4 fetuses.Conclusions PLSVC is always associated with congenital heart defects.The prognosis Of affected fetuses largely depends on whether or not the PLSVC is associated with a congenital heart defect.Prenatal diagnosis of PLSVC can help US plan perinatal counseling and ameliorate the postnatal course.

OBJECTIVE To study the mitochondrial toxicity effect of Radix Aconiti Lateralis Praepa?rata(Fuzi)on H9c2 cardiomyocytes. METHODS H9c2 cells were exposed to Fuzi decoction 6.25, 12.5,25,50 and 100 g·L-1 for 24 h. Fluorescence staining and CCK-8 assay were used to detect cell viability. H9c2 cells were exposed to Fuzi decoction 6.25,12.5 and 25 g · L-1 for 24 h,while the effect on mitochondrial membrane potential and reactive oxygen species(ROS)was detected by flow cytometry. The fluorescence molecular probe and laser scanning confocal microscope were used to observe the effect on Ca2+ in cells,Ca2+ and superoxide in mitochondria. The effect on ATP concentration in cells was detected via firefly luciferin and the expression of Pgc-1α,Bcl-2 and Bax mRNA evaluated by real-time PCR,while the expression of Pgc-1α protein was measured by Western blotting. RESULTS H9c2 cell viability was significantly inhibited by Fuzi decoction 12.5-100 g · L-1(P<0.05,P<0.01). The IC50 value was 47.4669 g · L-1,while the 95%confidence limit was 32.5997-69.1145 g · L-1. After treatment with Fuzi decoction 25 g · L-1 ,the fluorescence intensity of ROS in the normal control group increased from 204±67 to 454±78(P<0.05),that of mitochondrial superoxide increased from 5.4±1.8 to 26.8±8.5 (P<0.01),mitochondrial membrane potential decreased from 1.7±0.5 to 0.8±0.4(P<0.05),the fluores?cence intensity of intracellular Ca2+increased from 7.8±0.8 to 22.1±0.5(P<0.05)while that of mitochon?drial Ca2+decreased from 38.0±4.3 to 9.2±1.6(P<0.01),and intracellular ATP concentration decreased from (10.6 ± 0.4)μmol · g-1 to (5.3 ± 1.1)μmol · g-1 protein (P<0.05). qPCR and Western blotting test results showed that compared with the normal control group ,Pgc-1αand Bcl-2 mRNA relative expression level in Fuzi decoction 25 g·L-1 group was decreased from 1.00±0.10 and 1.00±0.10 to 0.09±0.06(P<0.01)and 0.43±0.06(P<0.01),respectively, while the relative expression of Bax mRNA was increased from 1.00 ± 0.03 to 1.17 ± 0.06 (P<0.05),and the expression of Pgc-1α protein was decreased from 0.906±0.034 to 0.541±0.003(P<0.01). CONCLUSION Fuzi has some mitochondrial toxicity to cardiomy?opathy. This effect arises from the combined action of different mechanisms. Mitochondrial toxicity of myocytes may account for the cardiac toxicity of Fuzi.

Combined with teaching practice, this study summarizes the teaching contents, methods and effect evaluation of pathological technology for professional postgraduates majoring in pathology. According to the basic conditions of postgraduates, the pathological technology training program has been formulated, student-centered heuristic teaching is carried out by using diversified teaching methods such as flipped classroom, interactive theoretical teaching is carried out by using the intelligent teaching platform, and practical teaching is carried out by using the problem-based learning mode, aiming to improve the theoretical literacy and practical level of pathological technology of professional postgraduates majoring in pathology, improve their clinical research thinking, and lay a foundation for clinical pathological diagnosis and scientific research in the future.

Objective:To study the risk factors of surgical therapy in neonates with necrotizing enterocolitis (NEC).Methods:From January 2016 to July 2020, neonates with a confirmed diagnosis of NEC (Bell's Stage Ⅱ and above) admitted to our hospital were retrospectively enrolled. They were assigned into surgical group and conservative group according to whether surgeries were performed. The conditions during perinatal period, clinical characteristics and laboratory examinations at the onset of NEC were compared between the two groups. Multivariate Logistic regression analysis was used to determine the risk factors of surgical therapy.Results:A total of 177 neonates with NEC were identified, including 62 cases (35.0%) in the surgical group and 115 cases (65.0%) in the conservative group. Multivariate Logistic regression analysis showed that male gender ( OR=3.178,95% CI 1.457~6.929, P=0.004), comorbidity with shock ( OR=3.434, 95% CI 1.112~10.607, P=0.032), mechanical ventilation>7 d before NEC onset ( OR=3.663, 95% CI 1.098~12.223, P=0.035) and lymphocytes <2.0×10 9/L ( OR=4.121, 95% CI 1.801~9.430, P=0.001) at the onset of NEC were independent risk factors for surgical therapy. Conclusions:Male gender, comorbidity with shock, mechanical ventilation >7 d before NEC and lymphocytopenia at the onset are independent risk factors for surgical therapy in neonates with NEC (Stage Ⅱ and above).

BACKGROUND:In recent years,with the development of biological scaffold materials and bioprinting technology,tissue-engineered bone has become a research hotspot in bone defect repair. OBJECTIVE:To summarize the current treatment methods for bone defects,summarize the biomaterials and bioprinting technology for preparing tissue-engineered bone scaffolds,and explore the application of biomaterials and printing technology in tissue engineering and the current challenges. METHODS:Search terms were"bone defect,tissue engineering,biomaterials,3D printing technology,4D printing technology,bioprinting,biological scaffold,bone repair"in Chinese and English.Relevant documents published from January 1,2009 to December 1,2022 were retrieved on CNKI,PubMed and Web of Science databases.After being screened by the first author,high-quality references were added.A total of 93 articles were included for review. RESULTS AND CONCLUSION:The main treatment methods for bone defects include bone transplantation,membrane-guided regeneration,gene therapy,bone tissue engineering,etc.The best treatment method is still uncertain.Bone tissue engineering technology is a new technology for the treatment of bone defects.It has become the focus of current research by constructing three-dimensional structures that can promote the proliferation and differentiation of osteoblasts and enhance the ability of bone formation.Biological scaffold materials are diverse,with their characteristics,advantages and disadvantages.A single biological material cannot meet the demand for tissue-engineered bone for the scaffold.Usually,multiple materials are combined to complement each other,which is to meet the demand for mechanical properties while taking into account the biological properties of the scaffold.Bioprinting technology can adjust the pore of the scaffold,build a complex spatial structure,and is more conducive to cell adhesion,proliferation and differentiation.The emerging 4D printing technology introduces"time"as the fourth dimension to make the prepared scaffold dynamic.With the synchronous development of smart materials,4D printing technology provides the possibility of efficient repair of bone defects in the future.

Objective:To study the risk factors of necrotizing enterocolitis (NEC) after surgery for intestinal atresia.Method:From August 2013 to June 2020, children with intestinal atresia receiving surgery in our hospital were retrospectively reviewed. The patients were assigned into NEC group and non-NEC group according to the occurrence of postoperative NEC. Demographic data and clinical characteristics were summarized and the risk factors for postoperative NEC were analyzed using Logistic regression analysis method.Result:A total of 96 infants were enrolled and NEC occurred in 13 patients (13.5%) after surgery for intestinal atresia. Compared with the non-NEC group, the NEC group were diagnosed of intestinal atresia [4.0(1.5,6.0)d vs. 1.4(0,2.0)d, P<0.001] and received surgery [4.8(2.0,7.0)d vs. 3.1(1.0,4.0)d, P=0.034] at later ages. The incidences of complex intestinal atresia [76.9%(10/13) vs. 44.6%(37/83), P=0.030] and blood transfusion [46.2%(6/13) vs. 13.3%(11/83), P=0.007] in the NEC group were higher than the non-NEC group. Logistic regression analysis showed that the age of initial diagnosis of intestinal atresia ( OR=3.346, 95% CI 1.493~7.500, P=0.003), complex intestinal atresia ( OR=9.052, 95% CI 1.119~73.209, P=0.039) and blood transfusion ( OR=6.835, 95% CI 1.399~33.380, P=0.018) were independent risk factors for postoperative NEC. Conclusion:Patients with delayed diagnosis of intestinal atresia, complex intestinal atresia and blood transfusion within 48 hours after surgery should be monitored for the occurrence of postoperative NEC.

The pathogenesis of Sjögren's syndrome （SS） was considered to involve external dryness， internal injured essence and blood， yin-deficiency endowment， and abnormal emotion and spirit， and it was believed that SS has the characteristics of dryness and impassability， and the pathogenesis of deficiency-excess in complexity. According to the theory “upper dryness treats qi， and lower dryness treats blood” in YE Gui's monograph “Medical Records for Clinical Guidance”， the dryness was divided into upper dryness and lower dryness syndromes to be differentiated and treated. When treating dryness syndrome， the patient should follow the characteristics of the five zang organs， using soft and cool medicines， avoiding warm and dry medicines， and valuing the animal products. The upper dryness could be treated with Sangxiang Decoction （桑杏汤） to clear the qi and moisten the dryness， Qiaohe Decoction （翘荷汤） to clear the upper with pungent-cool， and Shashen Maidong Decoction （沙参麦冬汤） to nourish yin and promote the production of body fluid. The lower dryness could be treated with Fumai Decoction （复脉汤） to enrich and nourish the five kinds of fluid. Liuwei Dihuang Pill （六味地黄丸） to nourish the kidneys and supplement essence， and Wuren Pill （五仁丸） to moisten the dryness and nourish the blood， which provided a new way of thinking for differentiation of the dryness syndrome.

Objective:To explore the innovation mode of independent transformation-oriented science and technology research program approval by medical new research & development (R&D) institution.Methods:Through analyzing the program layout, funds, review experts, undertaking units, chief experts and interdisciplinarity to summarize the experiences of the independent transformation-oriented municipal program approval by Haihe laboratory of Cell Ecosystem in 2022.Results:As a new medical R&D institution, which vigorously constructed by Tianjin, Haihe laboratory of Cell Ecosystem has carried out the practice of the independent transformation-oriented municipal program through the measures of layout of full-chain transformation, conducting transformation-oriented review, gathering high-level research talents, and emphasizing interdisciplinarity.Conclusions:The experiences of Haihe laboratory of Cell Ecosystem make significance for medical new R&D institutions to explore and cultivate scientific research program with transformation potential and to promote the transformation of scientific and technological achievements, which are powerful factors for new R&D institutions to play a role of pilot and provide important support to scientific and technological innovation and transformation.

Bromodomain containing protein 4 (BRD4), as an epigenetic reader, can specifically bind to the acetyl lysine residues of histones and has emerged as an attractive therapeutic target for various diseases, including cancer, cardiac remodeling and heart failure. Herein, we described the discovery of hit 5 bearing 4-phenylquinazoline skeleton through a high-throughput virtual screen using 2,003,400 compound library (enamine). Then, structure-activity relationship (SAR) study was performed and 47 new 4-phenylquinazoline derivatives toward BRD4 were further designed, synthesized and evaluated, using HTRF assay set up in our lab. Eventually, we identified compound C-34, which possessed better pharmacokinetic and physicochemical properties as well as lower cytotoxicity against NRCF and NRCM cells, compared to the positive control JQ1. Using computer-based molecular docking and cellular thermal shift assay, we further verified that C-34 could target BRD4 at molecular and cellular levels. Furthermore, treatment with C-34 effectively alleviated fibroblast activation in vitro and cardiac fibrosis in vivo, which was correlated with the decreased expression of BRD4 downstream target c-MYC as well as the depressed TGF-β1/Smad2/3 signaling pathway. Taken together, our findings indicate that novel BRD4 inhibitor C-34 tethering a 4-phenylquinazoline scaffold can serve as a lead compound for further development to treat fibrotic cardiovascular disease.