Objective:To explore the molecular mechanism by which the methionine adenosyltransferase 2A (MAT2A)/β-catenin/zinc finger E-box binding homeobox 1 (ZEB1)/epithelial-mesenchymal transition (EMT) pathway regulates neural tube defect (NTD) through intracellular S-adenosylmethionine (SAM).Methods:A mouse NTD model was induced using the SAM metabolic disorder inhibitor ethionine. Eighty specific pathogen-free C57BL/6 mice were divided into three groups: a normal group (36 mice), an ethionine group (46 mice), and an ethionine+SAM group (44 mice). Phosphate-buffered saline (PBS), ethionine, and ethionine+SAM were respectively injected intraperitoneally on embryonic day 7.5 (E7.5), and the mice were sacrificed on E10.5. Embryonic tissues were collected, and the morphology of embryos in each group was observed under a stereomicroscope. The interaction between ethionine and MAT2A was analyzed using Autodock software. The expression levels of MAT2A, β-catenin, ZEB1, and EMT-related proteins in the brain tissues of embryos from the three groups were measured using immunofluorescence, immunohistochemistry, Western blotting, enzyme-linked immunosorbent assay (ELISA), and real-time quantitative polymerase chain reaction (RT-qPCR). Variance analysis was used for intergroup comparisons.Results:(1) Autodock analysis results showed that MAT2A binds to ethionine through covalent bonds, exhibiting a complementary effect, thereby accelerating the expression of MAT2A. (2) After successful construction of the NTD model, normal embryos were plump with well-developed brains. NTD embryos showed delayed development, obvious anencephaly, unclosed neural tubes, and asymmetry. (3) The levels of SAM and SAH in the embryonic tissues of the ethionine group were significantly lower than those in the normal group (1 737.56±95.64 vs. 872.33±205.11, and 89.17±9.50 vs. 51.25±9.48, respectively). The SAM and SAH levels in the ethionine+SAM group was 1 197.00±222.27 and 66.61±12.25, significantly higher than those in the ethionine group ( P<0.017). Compared with the normal group and the ethionine+SAM group, the expression of MAT2A mRNA in the embryonic brain tissue of the ethionine group was significantly upregulated (1.00±0.00, 1.59±0.52, and 2.42±0.53, respectively, F=49.64, P<0.001; pairwise comparisons between groups P<0.017). (4) Compared with the normal group, the expression of Ctnnb1 in the ethionine group was reduced, and the expression of Ctnnb1 in the ethionine+SAM group was higher than that in the ethionine group (1.00±0.00, 0.38±0.16, and 0.76±0.10, respectively, F=149.03, P<0.001; pairwise comparisons between groups P<0.017). (5) The expression of ZEB1 in the ethionine group was higher than that in the normal group and the ethionine+SAM group (2.91±0.55, 1.00±0.00, and 1.61±0.20, respectively, F=150.01, P<0.001; pairwise comparisons between groups P<0.017). (6) The expression levels of E-cadherin and Vimentin in the ethionine group were lower than those in the normal group. In contrast, the expression of N-cadherin was higher than that in the normal group. After SAM supplementation, the expression levels of E-cadherin and Vimentin were upregulated, and the expression level of N-cadherin was downregulated (0.54±0.12, 1.00±0.00, and 0.72±0.14, respectively, F=87.44; 0.53±0.17, 1.00±0.00, and 0.76±0.09, F=87.44; 3.11±0.53, 1.00±0.00, and 2.13±0.56, F=95.54; all P<0.001; pairwise comparisons within the same index group P<0.017]). Conclusions:Ethionine promotes the expression of MAT2A, leading to reduced SAM production. Ethionine regulates the level of ZEB1 by increasing MAT2A and inhibits the EMT process to interfere with methionine cycle metabolism, ultimately resulting in NTD.

Objective To establish a purification,enrichment and test method of tetrodotoxin in blood.Methods Through the investigation of various hydrophilic chromatographic columns,the comparison of extraction effects of different types of solid phase extraction columns and the interference analysis of mixed peaks on qualitative ion pairs,the matrix influence of tetrodotoxin was reduced,and the detection sensitivity and qualitative accuracy were improved.Results Tetrodotoxin is highly polar and easily inhibited by the matrix,while conventional precipitation protein method has low sensitivity and isomer double peaks,and the C18 column is not reserved.After comprehensive comparative analysis,the weak cation exchange column PWC column is finally used for purification and enrichment.Complete elution was achieved using 0.5 mL 10%formic acid and 50%acetonitrile aqueous solution.Seperation was performed on an Atlantis HILIC column,with qualitative ion pairs set at m/z,320.10>162.15 and 284.15.The detection limit of the method was 0.061 ng/mL.Conclusion The established PWC solid-phase extraction-LC/MS detection method demonstrates significant purification efficacy,minimal matrix influence,unobstructed chromatographic peaks,markedly improved detection sensitivity.This approach is operationally simple,and applicable to forensic casework.

Objective To establish a purification,enrichment and test method of tetrodotoxin in blood.Methods Through the investigation of various hydrophilic chromatographic columns,the comparison of extraction effects of different types of solid phase extraction columns and the interference analysis of mixed peaks on qualitative ion pairs,the matrix influence of tetrodotoxin was reduced,and the detection sensitivity and qualitative accuracy were improved.Results Tetrodotoxin is highly polar and easily inhibited by the matrix,while conventional precipitation protein method has low sensitivity and isomer double peaks,and the C18 column is not reserved.After comprehensive comparative analysis,the weak cation exchange column PWC column is finally used for purification and enrichment.Complete elution was achieved using 0.5 mL 10%formic acid and 50%acetonitrile aqueous solution.Seperation was performed on an Atlantis HILIC column,with qualitative ion pairs set at m/z,320.10>162.15 and 284.15.The detection limit of the method was 0.061 ng/mL.Conclusion The established PWC solid-phase extraction-LC/MS detection method demonstrates significant purification efficacy,minimal matrix influence,unobstructed chromatographic peaks,markedly improved detection sensitivity.This approach is operationally simple,and applicable to forensic casework.

Objective:To explore the molecular mechanism by which the methionine adenosyltransferase 2A (MAT2A)/β-catenin/zinc finger E-box binding homeobox 1 (ZEB1)/epithelial-mesenchymal transition (EMT) pathway regulates neural tube defect (NTD) through intracellular S-adenosylmethionine (SAM).Methods:A mouse NTD model was induced using the SAM metabolic disorder inhibitor ethionine. Eighty specific pathogen-free C57BL/6 mice were divided into three groups: a normal group (36 mice), an ethionine group (46 mice), and an ethionine+SAM group (44 mice). Phosphate-buffered saline (PBS), ethionine, and ethionine+SAM were respectively injected intraperitoneally on embryonic day 7.5 (E7.5), and the mice were sacrificed on E10.5. Embryonic tissues were collected, and the morphology of embryos in each group was observed under a stereomicroscope. The interaction between ethionine and MAT2A was analyzed using Autodock software. The expression levels of MAT2A, β-catenin, ZEB1, and EMT-related proteins in the brain tissues of embryos from the three groups were measured using immunofluorescence, immunohistochemistry, Western blotting, enzyme-linked immunosorbent assay (ELISA), and real-time quantitative polymerase chain reaction (RT-qPCR). Variance analysis was used for intergroup comparisons.Results:(1) Autodock analysis results showed that MAT2A binds to ethionine through covalent bonds, exhibiting a complementary effect, thereby accelerating the expression of MAT2A. (2) After successful construction of the NTD model, normal embryos were plump with well-developed brains. NTD embryos showed delayed development, obvious anencephaly, unclosed neural tubes, and asymmetry. (3) The levels of SAM and SAH in the embryonic tissues of the ethionine group were significantly lower than those in the normal group (1 737.56±95.64 vs. 872.33±205.11, and 89.17±9.50 vs. 51.25±9.48, respectively). The SAM and SAH levels in the ethionine+SAM group was 1 197.00±222.27 and 66.61±12.25, significantly higher than those in the ethionine group ( P<0.017). Compared with the normal group and the ethionine+SAM group, the expression of MAT2A mRNA in the embryonic brain tissue of the ethionine group was significantly upregulated (1.00±0.00, 1.59±0.52, and 2.42±0.53, respectively, F=49.64, P<0.001; pairwise comparisons between groups P<0.017). (4) Compared with the normal group, the expression of Ctnnb1 in the ethionine group was reduced, and the expression of Ctnnb1 in the ethionine+SAM group was higher than that in the ethionine group (1.00±0.00, 0.38±0.16, and 0.76±0.10, respectively, F=149.03, P<0.001; pairwise comparisons between groups P<0.017). (5) The expression of ZEB1 in the ethionine group was higher than that in the normal group and the ethionine+SAM group (2.91±0.55, 1.00±0.00, and 1.61±0.20, respectively, F=150.01, P<0.001; pairwise comparisons between groups P<0.017). (6) The expression levels of E-cadherin and Vimentin in the ethionine group were lower than those in the normal group. In contrast, the expression of N-cadherin was higher than that in the normal group. After SAM supplementation, the expression levels of E-cadherin and Vimentin were upregulated, and the expression level of N-cadherin was downregulated (0.54±0.12, 1.00±0.00, and 0.72±0.14, respectively, F=87.44; 0.53±0.17, 1.00±0.00, and 0.76±0.09, F=87.44; 3.11±0.53, 1.00±0.00, and 2.13±0.56, F=95.54; all P<0.001; pairwise comparisons within the same index group P<0.017]). Conclusions:Ethionine promotes the expression of MAT2A, leading to reduced SAM production. Ethionine regulates the level of ZEB1 by increasing MAT2A and inhibits the EMT process to interfere with methionine cycle metabolism, ultimately resulting in NTD.

Background At present, occupational poisoning has become one of the most serious occupational diseases that jeopardize the health of workers in China, in addition to pneumoconiosis, with a wide range of impacts and heavy social and economic losses. Objective To analyze the characteristics and patterns of the incidence of occupational poisoning in Tianjin from 2006 to 2020, and to provide a scientific basis for the development of effective intervention measures and prevention strategies. Methods The Occupational Diseases and Health Hazards Monitoring Information System, a module of the China Disease Prevention and Control Information System, was the primary data source of the study. The case files of acute and chronic occupational poisoning diagnosed by occupational disease diagnostic institutions in Tianjin from January 1, 2006 to December 31, 2020 were retrieved from the system. The data included basic information, occupational history, disease characteristics, and employer information. Excel 2016 was used to establish database, and frequencies and composition ratios were reported. Results From 2006 to 2020, a total of 234 cases of occupational chemical poisoning were reported in Tianjin, including 49 cases of acute occupational poisoning (20.94%) and 185 cases of chronic occupational poisoning (79.06%). The number of acute occupational poisoning cases showed a rising and then falling trend, and the number of chronic occupational poisoning cases showed an overall decreasing trend. Acute occupational poisoning mainly occurred in the four districts around the city (22 cases, 44.90%), and chronic occupational poisoning mainly occurred in Binhai New Area (90 cases, 48.65%). More male cases were reported than female cases. The age of onset was concentrated at 45-55 years old. The acute occupational poisoning cases were concentrated in the group with less than 5 years of service (22 cases, 44.90%), mainly asphyxiating gas poisoning, and the highest incidence was reported in chemical raw materials and chemical products manufacturing industry. The chronic occupational poisoning cases were concentrated in the groups with a working age of 5-14 years (70 cases, 37.84%), mainly organic solvent poisoning, and the highest incidence was also reported in chemical raw materials and chemical products manufacturing industry. Conclusion The prevention and control of occupational poisoning as well as health surveillance and management in Tianjin shall be carried out in a hierarchical and focused manner in accordance with types of acute and chronic occupational poisoning chemicals in the city, regional economic differences, types of industries, and distribution of workers.

Objective:To detect gene mutations in a pedigree with dominant dystrophic epidermolysis bullosa (DDEB) .Methods:A 20-year-old male proband presented with repeated blisters, ulceration, pigmentation, scars on the limbs, and deformation of the nails/toenails after birth. There were 5 patients in the 3-generation family, and they all presented with typical skin lesions. Peripheral blood samples were obtained from 14 members of the pedigree (including the 5 patients) and 100 unrelated healthy controls. Whole-exome sequencing was performed in the proband to identify relevant mutation sites, which were then confirmed in the family by Sanger sequencing.Results:Genetic testing indicated that the proband and the other 4 patients all carried a missense mutation (c.7885G>A) in exon 107 of the COL7A1 gene, resulting in the substitution of glycine by arginine at amino acid position 2629 (p.G2629R). The mutation was identified neither in the 9 healthy relatives nor in the 100 unrelated healthy controls. The mutation co-segregated with DDEB in the family, and was not included in databases such as Pubmed, HGMD or ClinVar, suggesting it was a novel missense mutation. The amino acid encoded by this mutation may alter the structure of type Ⅶ collagen, thereby affecting its function.Conclusion:A novel missense mutation was identified in exon 107 of the COL7A1 gene in the family with DDEB, expanding the spectrum of mutations in the COL7A1 gene.

Senior care workers specializing in traditional Chinese medicine (TCM) healthcare have become an indispensable force in institutional care, community care, and home care. The first Chinese nursing service team aimed to improve the health of the elderly by providing continuous services for physical and mental well-being, disease prevention, physical amelioration, and overall health enhancement using TCM concepts, methods, and technologies. The primary purpose of formulating this TCM health and elderly care worker service specification was to standardize services within the TCM elderly care industry, ensuring that the elderly receive better health and elderly care services supported by technical expertise. This specification outlined the basic requirements for TCM health and elderly care workers, including standards for service content, service quality control, service evaluation, and improvement. It primarily focused on the content and requirements of TCM health and elderly care services, such as constitution identification, life care, acupoint healthcare, and TCM auxiliary nursing for elderly individuals with chronic diseases. This specification is applicable to TCM health and elderly care personnel at various levels of hospitals and healthcare institutions and is noted for its strong applicability and effectiveness.

Sports fatigue of the lower limbs is one of the important factors affecting sports performance. How to improve the anti-fatigue ability of the lower limbs during endurance exercise is the focus of the research field of human sports biomechanics. This study systematically reviewed the relevant literature on transcranial direct current stimulation (tDCS) intervention on lower limb endurance performance, summarized the effect of tDCS on lower limb endurance performance, and analyzed the influencing factors and potential mechanisms. The results showed that: tDCS intervention has a significant effect on the endurance performance of the whole lower limbs, but there is no unified conclusion on the effect on the endurance performance of the knee joint. The researchers deem that tDCS can increase the excitability of the primary motor cortex and reduce the activation of the supplementary motor area and the premotor area to producing a lower rating of perceived exertion, but cannot affect the perception of exercise-induced pain, and stimulation protocols varied across studies, which may be partly responsible. This study can provide a theoretical basis for exploring the central mechanism of tDCS to improve endurance performance, formulating rehabilitation and sports training programsfor different groups of people, and developing new stimulation equipment to enhance the human body’s anti fatigue ability.

Objective To study the effects and mechanisms of molecular targeted drug combination on multi-driven proliferation hepatocellular carcinoma SK-Hep-1 cells. Methods Four molecular targeted drugs (HG6-64-1, Dasatinib, Crizotinib, and Sunitinib) were used to treat SK-Hep-1 cells, and the monophasic kinetic analysis curve and two-phase analysis curve were drawn. Western blot analysis was used to detect the effects of the above drugs on key signaling pathways in SK-Hep-1 cells. MTT assay was used to detect the effects of the above drugs and their combination on the proliferation of SK-Hep-1 cells. Results Compared with the monophasic kinetic analysis curve, the biphase analysis curve could better fit the effects of molecular targeted drugs on SK-Hep-1 cells, which predicted that the combination of HG6-64-1, Dasatinib, and MK-2206 could effectively inhibit the proliferation of SK-Hep-1 cells. Conclusion Two-phase kinetic analysis can quantitatively describe the response of multi-driven proliferation hepatocellular carcinoma SK-Hep-1 cells to molecular targeted therapy. The combination of HG6-64-1, Dasatinib, and MK-2206 is a potential drug combination for the treatment of hepatocellular carcinoma.

HYD-PEP06, an endostatin-modified polypeptide, has been shown to produce effective anti-colorectal carcinoma effects through inhibiting epithelial-mesenchymal transition (EMT). However, whether HYD-PEP06 has similar suppressive effect on hepatocellular carcinoma (HCC) remained unknown. In this study, HYD-PEP06 inhibited metastasis and EMT but not proliferation