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According to the results of sensory evaluation performed by experts, 14 black tea samples were divided into two groups based on their aroma quality: high-quality and quality-deficient black tea. Using fast gas chromatography-electronic-nose (GC-E-Nose) and gas chromatography-mass spectrometry (GC-MS) combined with multivariate statistical analysis, discriminant analysis of the two groups were carried out, and the key differential components between these groups were selected. The results showed that 117-dimensional dataset was obtained by the fusion of the GC-E-Nose (44-dimensional) and GC-MS (73-dimensional) data and used to establish a model for accurate classification of the two types of black tea employing orthogonal partial least squares-discriminant analysis (OPLS-DA). The model’s explanatory and predictive capacity (R2Y = 0.976, Q2 = 0.959) were better than those of the model established based on the GC-E-Nose or GC-MS data. Based on variable important in projection (VIP) scores > 1.6 and P < 0.05, eight key aroma components including dimethyl sulfide (B3 and B25), β-ionone (A59), (3E)-4,8-dimethylnon-1,3,7-triene (A20), dihydroactinidiolide (A64), linalool (A17), phenylethyl alcohol (A19), δ-octyl lactone (A41) and γ-nonalatone (A45) were selected, which played an important role in the classification. These results showed that GC-E-Nose combined with GC-MS allows rapid and accurate discrimination between quality-deficient and high-quality black tea, which can be used as a supplement to traditional sensory evaluation, providing technical support for quality control and improvement of black tea.

Zn--Ni--PTFE composite coatings were prepared by pulse electrodeposition in chloride bath at different current densities. The effect of current density on the micromorphology, elemental composition, phase structure, and corrosion resistance of Zn--Ni--PTFE composite coating was studied by scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), X-ray diffractometry (XRD), and electrochemical test, respectively. The results showed that the Zn--Ni--PTFE composite coating electrodeposited at a current density of 2.5 A/dm² featured a thickness of 30.9 µm, uniform distribution of PTFE particles therein, and excellent corrosion resistance. [ABSTRACT FROM AUTHOR]

The electrodeposition of Ni--P--SiC composite was conducted on the surface of piston as an environmentally friendly technology for replacing the chromium electroplating. The SiC nanoparticles were modified by pickling prior to electrodeposition. The effect of cathodic current density on properties of the composite coating was studied using scanning electron microscope (SEM), energy-dispersive spectrometer (EDS), and microhardness tester. The wear resistance of the composite coating was examined by reciprocating friction and wear test, and its abrasion rate was characterized using three-dimensional profiler. The results showed that the dispersibility of silicon carbide particles is improved after being pickled, significantly reducing their agglomeration. The Ni--P--SiC composite coating electrodeposited at a current density of 7 A/dm² has a microhardness as high as 599.02 HV, and its friction coefficient and wear rate are both reduced by about 38% with respect to the substrate. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the efficacy of modified femoral neck osteotomy (mFNO) in the surgical treatment of patients with ankylosing spondylitis (AS) and severe spinal kyphosis combined with hip flexion contracture., Methods: A retrospective analysis was conducted on 61 AS patients (103 hips) with spinal kyphosis and hip flexion contracture who underwent pedicle subtraction osteotomy (PSO) and total hip arthroplasty (THA) from January 1, 2019 to November 15, 2023. Data on mFNO operation time, blood loss, preoperative and postoperative values of the angle of the trunk and lower limb (ATL), hip passive range of motion (ROM), visual analogue scale (VAS), and incidence of in-hospital complications were recorded. Statistical analysis was performed using paired-samples t test. P < 0.05 was considered statistically significant., Results: The study ultimately included 10 cases, 9 males and 1 female, with an average age of (41.30±9.03) years. These patients underwent surgery for a total of 52 times, including 19 hips both receiving mFNO and THA, and 14 times PSO. The average operation time for nine bilateral mFNO was (133.11±34.81) min, with blood loss of (433.33±187.10) mL. A unilateral mFNO took 60 min with 200 mL of blood loss. The preoperative ATL of 19 hips was 40.37°±13.66°, and the postoperative ATL value was 88.47°±12.46° ( P < 0.05). The preoperative VAS score was 0, while the postoperative VAS score was 5.95±1.51 ( P < 0.05). The preoperative hip extension ROM was 37.37°±18.13°, while the postoperative hip extension ROM was -4.95°±21.24° ( P < 0.05). Hip flexion ROM improved from 37.37°±18.13° to 50.79°±20.36° after FNO ( P < 0.05). There were three cases of in-hospital complications (3/52, 5.67%): One case of postoperative atelectasis following PSO (1/52, 1.92%), one greater trochanter fracture identified during THA (1/52, 1.92%), and one early dislocation post-THA (1/52, 1.92%)., Conclusion: mFNO significantly improves the ATL in AS patients with severe spinal kyphosis combined with hip flexion contracture, facilitating PSO and THA surgeries.

Objective: To analyze the effect of stump-preserving repair on rotator cuff healing and shoulder function for degenerative total rotator cuff tears., Methods: A clinical data of 152 patients with degenerative total rotator cuff tears, who underwent arthroscopic repair between April 2019 and May 2022, was retrospectively analyzed. There were 76 males and 76 females with an average age of 55.4 years (range, 24-78 years). MRI was performed at 6 months postoperatively to evaluate the rotator cuff healing according to the Sugaya classification. Pre- and intra-operative related factors were included for univariate analysis, including age (≥60 years/<60 years), gender (male/female), passive activity disorder (yes/no), disease duration (≤3 months/>3 months), stump-preserving repair (yes/no), use of suture bridge technique (yes/no), shoulder joint abduction angle at knotting (<45°/≥45°), acromioplasty (yes/no), glucocorticoid injection (yes/no), time for patients to start postoperative passive exercise (≤2 weeks/>2 weeks), and time for patients to start postoperative active exercise (≤3 months/>3 months). The influencing factors of tendon healing were screened; further logistic regression was used to conduct multivariate analysis to screen for risk factors. Two sets of data were balanced by propensity score matching. The American Shoulder and Elbow Surgeons (ASES) score and Constant-Murley score of shoulder joint function at 6 and 12 months postoperatively, as well as rotator cuff healing rate at 6 months postoperatively, were compared between groups based on whether or not stump-preserving repair was used., Results: All patients were followed up 12-33 months (mean, 23.8 months). MRI at 25-31 weeks postoperatively showed the 121 cases of rotator cuff healing and 31 cases of non healing. Univariate analysis showed that the disease duration, stump-preserving repair, shoulder joint abduction angle at knotting, and the time for patients to start postoperative active exercise were the influencing factors of rotator cuff healing ( P <0.05). Multivariate analysis showed that non-stump-preserving repair, shoulder abduction angle more than 45° at knotting, and the time to start active exercise within 3 months postoperatively were risk factors affecting rotator cuff healing ( P <0.05). A total of 51 pairs of cases were matched based on the grouping criteria of whether the disease duration exceeded 3 months, whether the shoulder abduction angle at knotting exceeded 45°, and whether the time to start postoperative active exercise exceeded 3 months. The rotator cuff healing rate, ASES score, and Constant-Murley score of the preserving repair group at 6 months postoperatively were superior to those of the non-preserving repair group, and the differences were significant ( P <0.05). There was no significant difference in ASES score and Constant-Murley score between the two groups at 12 months postoperatively ( P >0.05)., Conclusion: For degenerative total rotator cuff tears, the stump-preserving repair can shorten the healing time and promote the shoulder function recovery, but has no significant effect on shoulder function at 1 year postoperatively.

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths in the world. Due to the insidious onset and rapid progression and a lack of effective treatments, the prognosis of patients with HCC is extremely poor, with the average 5-year survival rate being less than 10%. The tumor microenvironment (TME), the internal environment in which HCC develops, can regulate the oncogenesis, development, invasion, and metastasis of HCC. During the process of cancer progression, HCC cells can regulate the biological behaviors of tumor cells, cancer-associated fibroblasts, cancer-associated immune cells, and other cells in the TME by releasing exosomes containing specific signals, thereby promoting cancer progression. However, the exact molecular mechanisms and the roles of exosomes in the specific cellular regulation of these processes are not fully understood. Herein, we summarized the TME components of HCC, the sources and the biological traits of exosomes in the TME, and the impact of mechanical factors on exosomes. In addition, special attention was given to the discussion of the effects of HCC-exosomes on different types of cells in the microenvironment. There are still many difficulties to be overcome before exosomes can be applied as carriers in clinical cancer treatment. First of all, the homogeneity of exosomes is difficult to ensure. Secondly, exosomes are mainly administered through subcutaneous injection. Although this method is simple and easy to implement, the absorption efficiency is not ideal. Thirdly, exosome extraction methods are limited in number and inefficient, making it difficult to prepare exosomes in large quantities. It is important to ensure that exosomes are used in sufficient quantities to trigger an effective tumor immune response, especially for exosome-mediated tumor immunotherapy. With the improvement in identification, isolation, and purification technology, exosomes are expected to be successfully used in the clinical diagnosis of early-stage HCC and the clinical treatment of liver cancer., Competing Interests: 利益冲突　所有作者均声明不存在利益冲突, (© 2024《四川大学学报（医学版）》编辑部 版权所有Copyright ©2024 Editorial Board of Journal of Sichuan University (Medical Sciences).)

Objective: The study aimed at association of family life, resilience and bullying on the use of tobacco in preadolescents., Methods: A total of 4792 students from 5 junior schools in Baise City were recruited with cluster-sampling method, filled with questionnaire of family life, resilience, parents&apos; Control, bullying, initiation of tobacco and smoking from Feb. to Nov. 2018.The sample comprised of 52.63% male students and 46.66% female students. The average age was(11.8±0.5). There were 56.78% of students lived in city and 43.22% of students lived in county town; The nationality of the sample was as follows: Zhuang nationality 90.00%, Han nationality 7.62%, other minorities(Yao nationality, Miao nationality, Yi nationality, et al)2.05%. The Logistic regression was used to explore the effect., Results: There were 9.75% and 6.97% of the sample reported initiation of tobacco and smoking respectively. The initiation of tobacco and smoking of boys were higher than that of girls(initiation of tobacco: χ~2=57.230, P&lt;0.001; smoking: χ~2=56.013, P&lt;0.001). The multivariate Logistic analysis showed gender was statistically significant factor of initiation of tobacco(OR=0.468, 95%CI 0.377-0.582) and smoking(OR=0.422, 95% CI 0.324-0.551), and age was statistically significant factor of initiation of tobacco(OR=1.609, 95% CI 1.446-1.791) and smoking(OR=2.026, 95%CI 1.776-2.310). Bullying was statistically significant factors of smoking(OR=1.106, 95% CI 1.073-1.140). Three protective factors were associated with a lower likelihood of initiation of tobacco(individual power: OR=0.964, 95% CI 0.951-0.976; family cohesion, OR=0.946, 95% CI 0.892-0.984; family rules, OR=0.949, 95%CI 0.930-0.965) and smoking(individual power: OR=0.962, 95% CI 0.947-0.977; family cohesion, OR=0.937, 95%CI 0.885-0.992; family rules, OR=0.952, 95%CI 0.932-0.973)in the final subscale model., Conclusion: Bullying increased the risk of smoking, while Individual power, family cohesion and family rules were associated with a lower likelihood of initiation of tobacco and smoking in preadolescents.

Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose.

Objective: To compared the clinical efficacy of laparoscopic repair (LR) versus open repair (OR) for perforated peptic ulcers., Methods: From January 2010 to June 2014, in Shanghai Tongji Hospital, 119 patients who were diagnosed as perforated peptic ulcers and planned to receive operation were prospectively enrolled. Patients were randomly divided into LR (58 patients) and OR(61 patients) group by computer. Intra-operative and postoperative parameters were compared between two groups. This study was registered as a randomized controlled trial by the China Clinical Trials Registry (registration No.ChiCTR-TRC-11001607)., Results: There was no significant difference in baseline data between two groups (all P>0.05). No significant differences of operation time, morbidity of postoperative complication, mortality, reoperation probability, decompression time, fluid diet recovery time and hospitalization cost were found between two groups (all P>0.05). As compared to OR group, LR group required less postoperative fentanyl [(0.74±0.33) mg vs. (1.04±0.39) mg, t=-4.519, P=0.000] and had shorter hospital stay [median 7(5 to 9) days vs. 8(7 to 10) days, U=-2.090, P=0.001]. In LR group, 3 patients(5.2%) had leakage in perforation site after surgery. One case received laparotomy on the second day after surgery for diffuse peritonitis. The other two received conservative treatment (total parenteral nutrition and enteral nutrition). There was no recurrence of perforation in OR group. One patient of each group died of multiple organ dysfunction syndrome (MODS) 22 days after surgery., Conclusion: LR may be preferable for treating perforated peptic ulcers than OR, however preventive measures during LR should be taken to avoid postopertive leak in perforation site.

To establish a gene regulation system compatible with biopharmaceutical industry and gene therapy, we constructed a fusion protein of biotin ligase from Bacillus subtilis (BS-BirA) and the trans-activation domain, and used its expression vector as the regulatory vector. Meanwhile, BS-BirA-specific operators were ligated upstream of attenuated CMV promoter to obtain the response vector. In this way, a novel eukaryotic gene regulation system responsive to biotin was established and named BS-Biotin-On system. BS-Biotin-On system was further investigated with the enhancing green fluorescent protein (EGFP) as the reporter gene. The results showed that our system was superior to the current similar regulation system in its higher induction ratio, and that the expression of interest gene could be tuned in a rapid and efficient manner by changing the biotin concentrations in the cultures, Our results show that the established system may provide a new alternative for the exogenous gene modulation.

In the light of Chinese hamster ovary (CHO) cell line 11G-S expressing human recombinant pro-urokinase, the differences of gene expression levels of the cells in different growth phases in both batch and fed-batch cultures were revealed by using gene chip technology. Then, based on the known cell cycle regulatory networks, the transcriptional profiling of the cell cycle regulatory networks of the cells in batch and fed-batch cultures was analyzed by using Genmapp software. Among the approximate 19 191 target genes in gene chip, the number of down-regulated genes was more than those of up-regulated genes of the cells in both batch and fed-batch cultures. The number of down-regulated genes of the cells in the recession phase in fed-batch culture was much more than that of the cells in batch culture. Comparative transcriptional analysis of the key cell cycle regulatory genes of the cells in both culture modes indicated that the cell proliferation and cell viability of the cells in both batch and fed-batch cultures were mainly regulated through down-regulating Cdk6, Cdk2, Cdc2a, Ccne1, Ccne2 genes of CDKs, Cyclin and CKI family and up-regulating Smad4 gene.

Currently, exogenous gene expression system based on retroviral vector has been widely used as efficient gene expression system in both gene therapeutic research and RNA interference. In this study, we evaluated the efficiency of exogenous gene expression mediated by the retroviral vector in mammalian cells. First, we constructed EGFP (enhanced green fluorescent protein) vector using pcDNA3.1(+) and retroviral vector pQCXIN as backbone vector respectively. Then, we transfected or infected HEK293 cells and CHO-K1 cells with above vector or corresponding retroviral virus, and measured the relative fluorescence intensity (RFI) of EGFP. The results showed that the RFI of the retroviral virus-infected cells was two times higher than that of the plasmid-transfected cells. Further experiments revealed repeated virus infection enhanced the expression of EGFP markedly, with RFI increasing twice after four rounds of virus infection. Furthermore, the EGFP expression in HEK293 cells mediated by the retroviral vector was more stable than transfected with plasmid pcDNA3.1(+). Finally, we further validated the efficiency of exogenous gene expression system based on the retroviral vector by expressing recombinant human activated protein C (rhAPC) in HEK293 cells. We obtained HEK293 cell lines with rhAPC expression between 10 and 15 microg/(10(6) cells d). In conclusion, the exogenous gene expression system based on the retroviral vector is an alternative method for the generation of stable and high-expressing mammalian cell lines.

Taking a suspension adapted recombinant CHO cell line, 11G-S expressing human Pro-urokinase (Pro-UK) as the object of study, the impacts of different feeding nutrients, the start time of feeding and cell inoculation density on the growth and Pro-UK production of 11G-S cells in serum-free fed-batch culture were evaluated in 100 mL shacking flasks. The results indicated that amino acids, serum-free supplements and inorganic salts played important role in cell growth, cell viability and protein expression. And the effects of cells fed-batch culture was much better with the initial cell inoculation density at 3 x 10(5)-4 x 10(5) cells/mL and the start time of feeding set at 72 h, a maximum viable cells density of 7.8 x 10(6) cells/mL with a peak Pro-UK activity at 8570 IU/mL was achieved during 12 d fed-batch culture. Further, the mu of the 11G-S cells at the middle phase of the fed-batch culture, and both the q(glu) and q(gln) of the 11G-S cells at the middle and later phases of the fed-batch culture was higher than that of the 11G-S cells at the same phase of the batch culture, respectively.

We constructed and identified cardiac-specific a-myosin heavy chain (alpha-MHC) promoter-driven expression vector. alpha-MHC promoter was amplified by PCR by using mouse genomic DNA as template and inserted into pGEM-T Easy vector. The inserted fragment was released by enzyme digestion, and then the cytomegalovirus (CMV) promoter in pcDNA3.1(+)-EGFP-hygro vector was replaced by the alpha-MHC promoter to construct alpha-MHC-EGFP expression vector. After identification with enzyme digestion, alpha-MHC-EGFP was transfected into mouse primary cardiomyocytes by electroporation. Green fluorescence could be observed in transfected cardiomyocytes, but not in transfected non-cardiomyocytes. Alpha-MHC-EGFP expression vector was specifically expressed in cardiomyocytes, and could be used to purify embryonic stem cell-derived cardiomyocytes.