OBJECTIVE: To prepare decellularized nerve grafts from alpha-1, 3-galactosyltransferase (GGTA1) gene-edited pigs and explore their biocompatibility for xenotransplantation. METHODS: The sciatic nerves from wild-type pigs and GGTA1 gene-edited pigs were obtained and underwent decellularization. The alpha-galactosidase (α-gal) content in the sciatic nerves of GGTA1 gene-edited pigs was detected by using IB4 fluorescence staining and ELISA method to verify the knockout status of the GGTA1 gene, and using human sciatic nerve as a control. HE staining and scanning electron microscopy observation were used to observe the structure of the nerve samples. Immunofluorescence staining and DNA content determination were used to evaluate the degree of decellularization of the nerve samples. Fourteen nude mice were taken, and subcutaneous capsules were prepared on both sides of the spine. Decellularized nerve samples of wild-type pigs ( n=7) and GGTA1 gene-edited pigs ( n=7) were randomly implanted in the subcutaneous capsules. Blood was drawn at 1, 3, 5, and 7 days after implantation to detect neutrophil counting. RESULTS: IB4 fluorescence staining and ELISA detection showed that GGTA1 gene was successfully knocked out in the nerves of GGTA1 gene-edited pigs. HE staining showed that the structure of the decellularized nerve from GGTA1 gene-edited pigs was well preserved; the nerve basement membrane tube structure was visible under scanning electron microscopy; no cell nuclei was observed, and the extracellular matrix components was retained in the nerve grafts by immunofluorescence staining; and the DNA content was significantly reduced when compared with the normal nerves ( P<0.05). In vivo experiments showed that the number of neutrophils in the two groups were similar at 1, 3, and 7 days after implantation, with no significant difference ( P>0.05); only at 5 days, the number of neutrophils was significantly lower in the GGTA1 gene-edited pigs than in the wild-type pigs ( P<0.05). CONCLUSION The decellularized nerve grafts from GGTA1 gene-edited pigs have well-preserved nerve structure, complete decellularization, retain the natural nerve basement membrane tube structure and components, and low immune response after xenotransplantation through in vitro experiments.
Animals ; Transplantation, Heterologous ; Galactosyltransferases/genetics* ; Sciatic Nerve/immunology* ; Swine ; Tissue Engineering/methods* ; Humans ; Graft Rejection/prevention & control* ; Gene Editing ; Mice ; Mice, Nude ; Heterografts/immunology* ; Animals, Genetically Modified ; Tissue Scaffolds ; Decellularized Extracellular Matrix

Objective To explore the predictive efficacy of platelet distribution width/platelet count(PDW/PLT)in retinopathy in patients with type 2 diabetes mellitus(T2DM).Methods A total of 120 pa-tients with T2DM admitted to Ma'anshan 17th Metallurgical Hospital from January 2020 to January 2023 were selected as the study group and were divided into the non-retinopathy group(n=69)and the retinopathy group(n=51).Another 80 healthy people who came to the hospital for physical examination during the same period were selected as the control group.The PDW and PLT were detected in all subjects after admission,and the PDW/PLT was calculated.The general data and biochemical indexes of each group were analyzed and compared.Receiver operating characteristic(ROC)curve was used to analyze the predictive efficacy of PDW/PLT in patients with T2DM complicated with retinopathy,and multivariate Logistic regression was used to analyze the related factors affecting patients with T2DM complicated with retinopathy.Results PDW and PDW/PLT in the study group were higher than those in the control group,and PLT was lower than that in the control group,and the differences were statistically significant(P＜0.05).PDW and PDW/PLT in the ret-inopathy group were higher than those in the non-retinopathy group,and PLT was lower than that in the non-retinopathy group,and the differences were statistically significant(P＜0.05).The ROC curve analysis re-sults showed that the area under the curve(AUC)of PDW for predicting retinopathy in T2DM patients was 0.840(95％CI:0.790-0.890),and the AUC of PLT for predicting retinopathy in T2DM patients was 0.765(95％CI:0.715-0.815),and the AUC of PDW/PLT for predicting retinopathy in T2DM patients was 0.906(95％CI:0.876-0.936).Multivariate Logistic stepwise regression analysis results showed that disease dura-tion(OR=3.047,95％CI:1.863-4.983),glycosylated hemoglobin(OR=3.963,95％CI:1.976-7.947),PDW/PLT(OR=4.191,95％CI:1.833-9.584)were risk factors for retinopathy in patients with T2DM(P＜0.05).Conclusion PDW/PLT is increased in T2DM patients with retinopathy,which could be used as an inde-pendent risk factor for T2DM patients with retinopathy,and has a high predictive value for retinopathy.

Objective:To develop the nursing staff's perception scale of patients′ suicide risk and test its reliability and validity, so as to provide basis for managers to formulate training strategies for nurses' suicide gatekeepers.Methods:This was a cross-sectional study. Based on cognitive-experiential self-theory, and on the basis of literature review and semi-structured interviews at home and abroad, a scale item pool was formed, and an initial scale was formed through expert inquiry and pre-investigation. In September, 2022, a cross-sectional survey was conducted among 459 nurses from three tertiary general hospitals and oncology hospitals by convenience sampling method in Jinan and Dezhou, Shandong Province. SPSS25.0 and AMOS23.0 software were used to analyze the items and test the reliability and validity of the scale.Results:The formal scale included three dimensions, namely, cognitive judgment, emotional evaluation, and concern, with 15 items in total. Exploratory factor analysis extracted three common factors, and the cumulative variance contribution rate was 67.845%. The results of confirmatory factor analysis showed that each test quantity of the fitness of the formal scale model is within the acceptable range and loads of 15 items in the corresponding factors were all >0.45; the content validity index S-CVI of the scale was 0.972, Cronbach′s α coefficient of the total scale was 0.907, and the half reliability was 0.814. Conclusion:The scale of nurses′ perception of patients′ suicide risk has good reliability and validity, and it can be used to evaluate nurses′ perceptions of patients′ suicide risk.

Objective To explore the clinical features of critical cases of coronavirus disease 2019 (COVID-19). Methods The clinical data of nine patients who were diagnosed with critical COVID-19 in Hainan General Hospital from January 21, 2020 to February 6, 2020 were retrospectively analyzed. RT-PCR testing for 2019 novel coronavirus (2019-nCoV) was performed with multi-sites synchronize specimens including pharyngeal swab, blood, excrement, and urine. The serum levels of leucocyte, C-reactive protein, procalcitonin and lactic acid between the improved group (five cases) and the deteriorated group (four cases) were compared. The t test was used for comparison of normally distributed continuous data between groups. Results There were eight males (88.9%) and 1 female enrolled. The patients aged 28-77 years old, with an age of (52.9±18.0) years. By March 4, 2020, all five cases in improved group were cured and discharged, three cases in deteriorated group died and 1case remained in critical condition. All multi-sites specimens of patients in improved group turned negative in 2-4 weeks of illness onset, while those of cases in deteriorated group showed sustained viral nucleic acid positive (up to 48th day of illness onset). The white blood cell counts ((13.52±8.24)×10 9 /L vs (10.49±4.46) ×10 9 /L), C-reactive protein ((139.71±87.46) mg/L vs (78.60±55.40) mg/L) and procalcitonin ((2.32±4.03) ng/mL vs (0.28±0.58) ng/mL) , lactic acid ((3.70±4.14) mmol/L vs (2.33±0.53) mmol/L) in deteriorated group were all significantly higher than those in improved group ( t =2.908, 5.009, 4.391 and 2.942, respectively, all P <0.01). A rapid rise of serum IL-6 level up to 8 500 pg/mL was observed in one patient three days prior to death. Conclusion Among the patients with critical COVID-19, serum levels of inflammatory cytokines of the death cases are higher than those of improved and discharged cases.