Genetic analysis of developmental and epileptic encephalopathy caused by novel biallelic SZT2 gene mutations in three Chinese Han infants: a case series and literature review.

BACKGROUND: Developmental and epileptic encephalopathy (DEE) exhibits phenotypic and genetic heterogeneity. Biallelic variants of the SZT2 gene can lead to DEE18, of which few cases have been reported. This study aimed to analyze the potential pathogenic factors in three cases of DEE18. METHODS: Trio-whole exome sequencing and crystal structure simulation analysis were performed, along with a literature review of DEE18 cases. RESULTS: All three patients had compound heterozygous variants in the SZT2 gene (patient 1, c.2887A > G/c.7970G > A; patient 2, c.3508A > G/c.7936C > T; and patient 3, c.2489G > T/c.8640_8641insC). The variants were predicted to have structural effects on the protein. Particularly, c.3508A > G/p.Ser1170Gly may lead to impaired binding of SZT2 to GATOR1, potentially resulting in the overactivation of the mTORC1 signaling pathway, causing seizures. Through the literature review, we observed that 27 patients with DEE had different degrees of intellectual and developmental disorders (DDs), and the variants leading to protein truncation cause severe DD and refractory epilepsy. Therefore, the phenotypic severity of patients may be related to the residual activity of variant SZT2 protein. CONCLUSION: We provide recently developed knowledge on the DEE18 genotype-phenotype spectrum and suggest that gene detection is of great value for the accurate diagnosis of patients with early-onset epilepsy. Further research is required for the development of individualized interventions for patients with DEE.

Relationship between the sodium fluorescein yellow fluorescence boundary and the actual boundary of high-grade gliomas during surgical resection.

OBJECTIVE: Resection of high-grade glioma with sodium fluorescein can improve the resection rate of the glioma and improve survival. However, it is unclear whether the yellow fluorescence boundary of the high-grade glioma is consistent with the actual boundary of the tumor. This study explores the yellow fluorescence boundary and the actual tumor boundary in high-grade glioma surgery. METHODS: This is a retrospective analysis of 10 patients with high-grade gliomas who underwent tumor visualization with sodium fluorescein. After staining of the tumor, random selections of both developed and non-developed yellow fluorescent border tissue at the fluorescence chromogenic boundary were made, followed by pathological examination. Claudin-5, an important component of the tight connections between vascular endothelial cells, was assessed by immunohistochemistry and qRT-PCR in the tumor and surrounding tissues in order to determine the tumor cell content of the tissue, blood-brain barrier damage, and vascular proliferation. The yellow fluorescence boundary was compared with the actual tumor boundary and the results analyzed. RESULTS: Tumor cells were still detected outside the yellow fluorescence boundary during high-grade glioma surgery (P < 0.05). Claudin-5 expression was higher in high-grade gliomas than in adjacent normal tissues (P < 0.05), while disconnected Claudin-5 expression was associated with intraoperative yellow fluorescence imaging (r = 0.67). CONCLUSIONS: There is a difference between the yellow fluorescence boundary and the actual boundary of the tumor in high-grade glioma, and there are glioma cell infiltrations in the brain tissue of the undeveloped yellow fluorescent border. To ensure patient recovery and function, it is recommended that tumor resection be expanded based on yellow fluorescence visualization. Claudin-5 is overall up-regulated in high-grade gliomas, but some Claudin-5 expression is disconnected. This Claudin-5 expression pattern may be related to the development of yellow fluorescence.

[Effect of health education on farmers' intention of joining in the new rural cooperative medical system].

OBJECTIVE: To evaluate the impact of health education intervention on promoting rural residents to join new rural cooperative medical system (NCMS) and their intention of joining NCMS based on Health Belief Model in project areas in Henan and Jilin Provinces. METHODS: Quasi-experiment study was used to evaluate intervention impact. Following the evidence-based approach, according to needs assessment, a half-year health education intervention was implemented among farmers in the experimental counties in Henan and Jilin Provinces respectively. A questionnaire survey was conducted among farmers in intervention and control counties before and after intervention, and intervention impact was evaluated by comparing the indicators' changes in intervention and control counties. RESULTS: After health education intervention, the knowledge level of farmers in two intervention counties increased by 29.0% and 37.8% respectively, their scores of perceived threatens of health risk and perceived barriers of joining NCMS among the respondents were decreased. Meanwhile, their score of perceived benefit of joining NCMS were increased, and the rate of willingness to join NCMS increased remarkably in both intervention counties. CONCLUSION: Health education was effective and helpful in increasing farmer's knowledge, understanding and cognitive level of NCMS, and it should play an important role for the sustainable development of NCMS.

Transforming and secreting expression of human egf in mutant strain WYBS2001 of Bacillus and its functions.

Mutant strain WYBS2001 of B. subtilis with strong anti-pathogenic activity was obtained by mutagenic ultraviolet rays. The gene fragment of Human Epidermal Growth Factor(hegf) of 175 bp was synthesized by PCR and the restriction sites Pst I and Hind III, original code and the signal sequence CTTAGA of secreting vector pUS186 were induced in the fragment. The DNA sequencing result revealed that the synthesized fragment was identical with that of human egf. Then the biological engineering strain WYBS2001T with human egf was obtained by transforming pUSE which was constructed by cloning egf into the secreting plasmid pUS186, into mutant strain WYBS2001. The result of RIA showed that hEGF can be found in the supernatant of the cultures and its content was 7.6 ng/ml. And the content can be increased if the proteinase inhibitor was added into the medium. After several generations' culturing, WYBS2001T positive engineering strain can still secrete and express hEGF steadily. The result of experiment showed hEGF had biological activity of proliferation and growth of human cell K562 in vitro. WYBS2001T engineering strain had obvious effect on healing the burned animals' models. This research showed microecological gene-engineering bacteria has good applying foreground.

[Study on transformation of snowdrop lectin gene to chrysanthemum and aphid resistance of the transgenic plants].

Agrobacterium-mediated transformation in chrysanthemum was studied to prevent the insect pest of aphid (Mizus persicae). The gna gene was successfully transferred into chrysanthemum by leaf dish, and 93 transgenic clones were obtained. The highest transformation frequency 11.21% was achieved on the optimization facts, which were medium YEB with pH5.6, bacterial concentration OD600 = 0.4, precultivation for one day, cocultivation for four days, the cocultivation media supplemented with GA3 0.5 mg/L and leaf explants growed for 45 days. The results from PCR and FQ-PCR analysis confirmed that gna gene was integrated into the genome of chrysanthemum plants. The insect bioassay with aphid showed that the aphid resistance of different transgenic plants was difference, and the rate of aphid population inhibition of them were from 10% to 84% with an average rate of 39.4%. The leaf-extracts from different transgenic plants showed varying actinties in red-blood cell bioassay.

[Establishment of high-yield suspension cell line of Curcuma zedoaria (Berg.) Rosc and study on the volatile oil synthesis-controlling with precursors].

The condition for high-yield suspension cell line and the precursors of volatile oil synthesis of Curcuma zedoaria (Berg.) Rosc were studied. The results showed that the light yellow particle callus was suitable for establishment of the high-yield suspension cell line. The optimum conditions for cell growth were MS medium added 15-30 g/L glucose and 15-30 g/L sucrose (1:1) as carbon source, the total concentration of 80 mmol/L nitrogen source combined NH4+ with NO3- (1:3), hormones of 3.0-5.0 mg/L 6-BA, 1.0 mg/L 2,4-D and dark culture after 10-15 days light culture. The 229 g/L cell (FW) and 2.11% content of volatile oil were obtained in vitro. The addition of precursors of calcium pantothenate, ammonium acetate and potassium acetate during the middle period of the cell suspension culture enhanced the volatile oil content respectively, and ammonium acetate was most effective among them. The highest yield of volatile oil obtained was 3.11% and 8.27 g/L respectively , which was 1.25 and 1.2 times of the control group.