In June 2018,sows at a pig farm in Jiamusi,Heilongjiang Province,suffered a large num-ber of miscarriages,and subsequently weaned piglets at the farm began to show persistent high fe-ver symptoms at around 35 days of age,with some pigs having a fever of more than 41.5 ℃.In or-der to determine the cause of this outbreak,63 clinical samples from this farm were tested.The re-sults showed that 60 out of 63 samples were positive for the porcine reproductive and respiratory syndrome virus(PRRSV)antigen.Subsequently,PRRSV antigen-positive plasmid was transfected into African green monkey embryonic kidney cells(Marc-145),and after three generations of blind transmission,indirect immunofluorescence assay(IFA)was performed.The results showed that one PRRSV strain,named HLJ38,was successfully isolated.Then the whole genome of HLJ38 strain was sequenced and then analyzed in detail by bioinformatics software.Sequence analysis showed that there were three deletions of 131 amino acids(323-433 aa,483 aa and 504-522 aa)in the derived sequence of Nsp2 gene of HLJ38 strain,which was consistent with the molecular ge-netic marker of NADC30 PRRSV.The phylogenetic tree analysis showed that HLJ38 and NADC30 PRRSV in GenBank belong to lineage 1 subgroup,and the nucleotide homology of HLJ38 and NADC30 PRRSV in GenBank was only 85.2％and 84.6％.Recombinant analysis showed that HLJ38 was a recombinant NADC30-like PRRSV,and the recombinant gene fragments were de-rived from multiple strains,among which the fragment of 1-201 nt was provided by VR2332 strain and fragment of 6 641-8 061 nt derived from the HP-PRRSV strain.In summary,the re-sults showed that the outbreak in this pig farm may be caused by the recombination of PRRSV strains among different lineages,and the recombinant circulating strains not only have certain pathogenicity but also suggest that the existing commercial vaccines provide limited cross-protec-tion against them.Recombination between different lineages increases the genetic diversity of PRRSV and aggravates the difficulty of prevention and control of PRRS in pig farms.Therefore,it is necessary to continuously monitor the epidemic dynamics of PRRSV in pig farms and take effec-tive measures in time to curb the spread of PRRS.

BACKGROUND:Oligodendrocyte precursor cells are seed cells for the treatment of white matter damage diseases.Establishing an efficient and stable in vitro differentiation method is an important prerequisite for clinical translational research.OBJECTIVE:To investigate the effect of fibronectin on biological characteristics such as proliferation,migration,and differentiation of oligodendrocyte precursor cells derived from human neural stem cells.METHODS:Human neural stem cells cultured in suspension were digested into single cells using Accutase.The expression of specific markers Nestin,Sox2,Vimentin,CD133,and Musashi was detected by flow cytometry.The single cells of human neural stem cells were resuspended in oligodendrocyte precursor cell medium and seeded in six-well plates coated with different concentrations of fibronectin(0,1,2.5,5,and 10 μg/mL).Accutase digestion was performed after 7 days of culture.Cells were counted by trypan staining.Fibronectin-coated group with the strongest amplification ability and the oligodendrocyte precursor cells without fibronectin-coated group were selected for further tests.The migration ability of the two groups of cells was detected by Transwell.Flow cytometry was used to detect the expression of Olig2,Sox10,and PDGFR-α.Oligodendrocyte precursor cells were induced to differentiate into oligodendrocytes for 3 weeks,and the expression of Galc in differentiated cells was detected by immunofluorescence staining.RESULTS AND CONCLUSION:(1)H uman neural stem cells grew in suspension spheres.Flow cytometry showed that human neural stem cells highly expressed Nestin,Sox2,Vimentin,CD133,and Musashi.(2)The cell bodies of oligodendrocyte precursor cells induced by human neural stem cells were round or oval,with strong refractive nature and bipolar or tertiary protrusions.Compared with the 0 μg/mL fibronectin coating group,there was a significant difference in the amplification ability of oligodendrocyte precursor cells in the 2.5,5,and 10 μg/mL fibronectin coating groups(P＜0.05).The amplification ability of oligodendrocyte precursor cells was the strongest when the fibronectin concentration was 10 μg/mL.(3)Flow cytometry results showed that the oligodendrocyte precursor cell markers 0Iig2,Sox10,and PDGFR-α were highly expressed in the 0 and 10 μg/mL fibronectin coating groups,and there was no significant difference between the two groups(P＞0.05).(4)Transwell chamber assay results showed that compared with the 0 μg/mL fibronectin-coated group,the migration ability of oligodendrocyte precursor cells in the 10 μg/mL fibronectin-coated group was increased(P＜0.01).(5)After 3 weeks of differentiation into oligodendrocytes,oligodendrocyte precursor cells showed complex morphology with multiple branches,grids or membrane sheets.Immunofluorescence staining results showed that there was no statistical difference in the Galc positive rate of oligodendrocytes between the two groups(P＞0.05).These findings indicate that when the concentration of fibronectin coated well plate is 10 μg/mL,the proliferation and migration of oligodendrocyte precursor cells are the strongest,but it does not affect the expression of oligodendrocyte precursor cells-specific markers Olig2,Sox10,and PDGFR-α and their differentiation into oligodendrocytes.

AIM:We investigated the survival,migration and differentiation abilities of human oligodendro-cyte precursor cells(hOPC)in the brains of mice with vascular dementia(VaD),the effects of hOPC on cerebral white matter,and the underlying mechanisms.METHODS:Mouse VaD model was constructed using the bilateral common ca-rotid artery stenosis method,and the mice were randomly divided into sham,VaD and hOPC groups.Eight weeks after model establishment,the mice in VaD and hOPC groups received equal volume of vehicle(PBS)and hOPC solution,re-spectively,through the corpus callosum.Survival,migration and differentiation of hOPC in the brain were observed by im-munofluorescence staining at 4 and 12 weeks after transplantation.Twelve weeks after transplantation,the effects of hOPC on mouse brain white matter were detected by immunofluorescence staining of myelin basic protein(MBP),myelin-associ-ated glycoprotein(MAG),neurofilament protein 200(NF200)and non-phosphorylated neurofilament H(using monoclo-nal antibody SMI32),and by water maze experiments.Paracrine signaling by hOPC was explored using immunofluores-cence staining for vascular endothelial growth factor(VEGF).RESULTS:The hOPC survived in the brains of VaD mice for 12 weeks,migrated to damaged white matter areas,and partially differentiated into mature oligodendrocytes(approxi-mately 64%).Twelve weeks after transplantation,hOPC significantly increased the fluorescence intensity of MBP,MAG,and NF200(P<0.05 or P<0.01)and decreased the fluorescence intensity of SMI32(P<0.01).The VEGF expression in hOPC-treated mice was significantly higher than that in sham and VaD groups(P<0.01).The difference in water maze test performance between hOPC and sham groups was not statistically significant(P>0.05).The mice in hOPC group had a shorter latency than those in VaD group(P<0.05 or P<0.01),and performed more platform crossings than those in VaD group(P<0.05).CONCLUSION:The hOPC can survive,migrate and differentiate in the brains of VaD mice,attenuate cerebral white matter lesions,and improve cognitive function.These improvements may be attributed to cell replacement and paracrine effects.

Objective:To construct a framework for evaluating the quality of health economic evaluation methodology based on the pragmatic clinical trial.Methods:An evaluation framework was constructed based on existing quality evaluation tools for health economic evaluation other quality evaluation tools.The weights of each item in the framework were determined by the Delphi method,and the weighted average was calculated using the expert authority coefficient.Results:A total of 23 experts were consulted,and the expert authority coefficients were 0.88 and 0.90,respectively.The results of the Wilcoxon signed-rank test showed no statistically signifi-cant differences among the expert opinions in two rounds(P＞0.05).Finally,a framework with 3 dimensions and 8 items was estab-lished.Conclusion:The evaluation framework has high scientificity and reliability.

Objective:To investigate the effect of risk forewarning hierarchical management on mental state,major adverse cardiovascular events(MACE)and quality of life in patients with acute coronary syndrome after percutane-ous coronary intervention(PCI).Methods:This randomized controlled study enrolled 152 patients with acute coro-nary syndrome who underwent PCI in the First Hospital of Qinhuangdao between July 2021 and June 2023.Patients were randomly divided into control group(n=76,conventional intervention program)and intervention group(n=76,additional risk forewarning hierarchical management).After 3-month intervention,mental state[Hamilton anxiety scale(HAMA)and Hamilton depression scale(HAMD)scores],health literacy[perceived knowledge scale for coronary heart diseases(PKS-CHD)score],quality of life[Seattle angina questionnaire(SAQ)score]and in-cidence of MACE were compared between the two groups.Results:Compared to those in the control group,patients in the intervention group had significantly higher total score of PKS-CHD[(35.08±3.59)points vs.(30.53±3.85)points],SAQ dimensional scores of physical limitation[(15.24±1.73)points vs.(13.26±1.45)points],an-ginal stability[(16.84±1.39)points vs.(15.18±1.48)points],disease perception[(17.00±1.46)points vs.(14.34±1.93)points],anginal frequency[(18.55±1.18)points vs.(16.11±1.39)points]and treatment satis-faction[(17.12±1.45)points vs.(14.04±1.93)points](P＜0.001 all),and significantly lower HAMA score[(11.89±1.64)points vs.(13.55±1.56)points],HAMD score[(12.61±1.76)points vs.(16.42±1.92)points]and the incidence of MACE(8.00％vs.28.38％)(P＜0.001 all).Conclusion:Risk forewarning hierarchical man-agement may effectively relieve patients'negative emotions,improve their health literacy and quality of life,and significantly reduce the risk of MACE in patients with acute coronary syndrome after PCI.

BACKGROUND:Oligodendrocyte precursor cells are seed cells for the treatment of white matter damage diseases.Establishing an efficient and stable in vitro differentiation method is an important prerequisite for clinical translational research.OBJECTIVE:To investigate the effect of fibronectin on biological characteristics such as proliferation,migration,and differentiation of oligodendrocyte precursor cells derived from human neural stem cells.METHODS:Human neural stem cells cultured in suspension were digested into single cells using Accutase.The expression of specific markers Nestin,Sox2,Vimentin,CD133,and Musashi was detected by flow cytometry.The single cells of human neural stem cells were resuspended in oligodendrocyte precursor cell medium and seeded in six-well plates coated with different concentrations of fibronectin(0,1,2.5,5,and 10 μg/mL).Accutase digestion was performed after 7 days of culture.Cells were counted by trypan staining.Fibronectin-coated group with the strongest amplification ability and the oligodendrocyte precursor cells without fibronectin-coated group were selected for further tests.The migration ability of the two groups of cells was detected by Transwell.Flow cytometry was used to detect the expression of Olig2,Sox10,and PDGFR-α.Oligodendrocyte precursor cells were induced to differentiate into oligodendrocytes for 3 weeks,and the expression of Galc in differentiated cells was detected by immunofluorescence staining.RESULTS AND CONCLUSION:(1)H uman neural stem cells grew in suspension spheres.Flow cytometry showed that human neural stem cells highly expressed Nestin,Sox2,Vimentin,CD133,and Musashi.(2)The cell bodies of oligodendrocyte precursor cells induced by human neural stem cells were round or oval,with strong refractive nature and bipolar or tertiary protrusions.Compared with the 0 μg/mL fibronectin coating group,there was a significant difference in the amplification ability of oligodendrocyte precursor cells in the 2.5,5,and 10 μg/mL fibronectin coating groups(P＜0.05).The amplification ability of oligodendrocyte precursor cells was the strongest when the fibronectin concentration was 10 μg/mL.(3)Flow cytometry results showed that the oligodendrocyte precursor cell markers 0Iig2,Sox10,and PDGFR-α were highly expressed in the 0 and 10 μg/mL fibronectin coating groups,and there was no significant difference between the two groups(P＞0.05).(4)Transwell chamber assay results showed that compared with the 0 μg/mL fibronectin-coated group,the migration ability of oligodendrocyte precursor cells in the 10 μg/mL fibronectin-coated group was increased(P＜0.01).(5)After 3 weeks of differentiation into oligodendrocytes,oligodendrocyte precursor cells showed complex morphology with multiple branches,grids or membrane sheets.Immunofluorescence staining results showed that there was no statistical difference in the Galc positive rate of oligodendrocytes between the two groups(P＞0.05).These findings indicate that when the concentration of fibronectin coated well plate is 10 μg/mL,the proliferation and migration of oligodendrocyte precursor cells are the strongest,but it does not affect the expression of oligodendrocyte precursor cells-specific markers Olig2,Sox10,and PDGFR-α and their differentiation into oligodendrocytes.

Objective:To investigate abnormal blood lipids of military flying personnel and related contributors in order to provide data for health support to military flying personnel.Methods:The physical examination data of 358 military flying personnel between November 2022 and April 2023 was retrospectively analyzed. The flying personnel were divided into 3 groups by age (20-≤29 years, 30-≤39 years and ≥40 years), 3 groups by aircraft types (helicopters, fighters and trainers), 2 groups by flying hours (≤2 000 h and >2 000 h) and 2 groups by body mass index (<24.0 kg/m 2 and ≥24.0 kg/m 2). The blood lipid abnormalities of these military flying personnel were compared across groups. Results:There was a significant difference in levels of total cholesterol ( F=3.77, P=0.024), triglyceride ( H=12.10, P=0.002) and low-density lipoprotein cholesterol ( F=5.61, P=0.004) across age groups, but there was no significant difference in levels of high-density lipoprotein cholesterol ( P>0.05). There was no significant difference in levels of total cholesterol, triglyceride, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol between military flying personnel working for different types of aircraft (all P>0.05). Levels of total cholesterol ( F=8.69, P=0.003), triglyceride ( Z=2.57, P=0.010) and high-density lipoprotein cholesterol ( F=10.61, P=0.001) in the >2 000 h group were significantly higher than those in the ≤2 000 h group. There was no significant difference in levels of low-density lipoprotein cholesterol between groups of different flying hours ( P>0.05). The levels of total cholesterol ( F=10.39, P=0.002), triglyceride ( Z=4.05, P<0.001) and low-density lipoprotein cholesterol ( F=12.73, P<0.001) in the body mass index ≥24 kg/m 2 group were significantly higher than those in the body mass index <24 kg/m 2 group. There was no significant difference in levels of high-density lipoprotein cholesterol between different body mass index groups ( P>0.05). Conclusions:There were differences in the blood lipid abnormality among military flying personnel with different ages, flying hours and body mass index. It is critical to better manage the blood lipid indicators of flying personnel, provide early intervention and treatment, improve the rate of normal blood lipids, and ensure the health of flying personnel.

Objective:To investigate the effect of risk forewarning hierarchical management on mental state,major adverse cardiovascular events(MACE)and quality of life in patients with acute coronary syndrome after percutane-ous coronary intervention(PCI).Methods:This randomized controlled study enrolled 152 patients with acute coro-nary syndrome who underwent PCI in the First Hospital of Qinhuangdao between July 2021 and June 2023.Patients were randomly divided into control group(n=76,conventional intervention program)and intervention group(n=76,additional risk forewarning hierarchical management).After 3-month intervention,mental state[Hamilton anxiety scale(HAMA)and Hamilton depression scale(HAMD)scores],health literacy[perceived knowledge scale for coronary heart diseases(PKS-CHD)score],quality of life[Seattle angina questionnaire(SAQ)score]and in-cidence of MACE were compared between the two groups.Results:Compared to those in the control group,patients in the intervention group had significantly higher total score of PKS-CHD[(35.08±3.59)points vs.(30.53±3.85)points],SAQ dimensional scores of physical limitation[(15.24±1.73)points vs.(13.26±1.45)points],an-ginal stability[(16.84±1.39)points vs.(15.18±1.48)points],disease perception[(17.00±1.46)points vs.(14.34±1.93)points],anginal frequency[(18.55±1.18)points vs.(16.11±1.39)points]and treatment satis-faction[(17.12±1.45)points vs.(14.04±1.93)points](P＜0.001 all),and significantly lower HAMA score[(11.89±1.64)points vs.(13.55±1.56)points],HAMD score[(12.61±1.76)points vs.(16.42±1.92)points]and the incidence of MACE(8.00％vs.28.38％)(P＜0.001 all).Conclusion:Risk forewarning hierarchical man-agement may effectively relieve patients'negative emotions,improve their health literacy and quality of life,and significantly reduce the risk of MACE in patients with acute coronary syndrome after PCI.

To summarize the nursing experience of a patient with uremia on maintenance hemodialysis complicated by recurrent ventricular tachycardia and treated with transcatheter radiofrequency ablation.Key nursing interventions included:dynamically assessing the patient's coagulation and bleeding status,being vigilant against the occurrence of deep vein thrombosis,and preventing local and major organ bleeding;implementing goal-oriented volume management strategies to prevent electrolyte disorders;the strengthened management of vascular access to reduce risks of stenosis or occlusion in the arteriovenous fistula;conducting precise assessment and comprehensive intervention to reduce the patient's psychological and mental burden.After careful treatment and nursing care,the patient was stable and discharged on the 6th postoperative day.During the 2-month outpatient follow-up,cardiac function indicators were normal,and the fistula was unobstructed,and the patient recovered well.

PURPOSE: To investigate the protective effect of sub-hypothermic mechanical perfusion combined with membrane lung oxygenation on ischemic hypoxic injury of yorkshire brain tissue caused by traumatic blood loss. METHODS: This article performed a random controlled trial. Brain tissue of 7 yorkshire was selected and divided into the sub-low temperature anterograde machine perfusion group (n = 4) and the blank control group (n = 3) using the random number table method. A yorkshire model of brain tissue injury induced by traumatic blood loss was established. Firstly, the perfusion temperature and blood oxygen saturation were monitored in real-time during the perfusion process. The number of red blood cells, hemoglobin content, NA⁺, K⁺, and Ca²⁺ ions concentrations and pH of the perfusate were detected. Following perfusion, we specifically examined the parietal lobe to assess its water content. The prefrontal cortex and hippocampus were then dissected for histological evaluation, allowing us to investigate potential regional differences in tissue injury. The blank control group was sampled directly before perfusion. All statistical analyses and graphs were performed using GraphPad Prism 8.0 Student t-test. All tests were two-sided, and p value of less than 0.05 was considered to indicate statistical significance. RESULTS: The contents of red blood cells and hemoglobin during perfusion were maintained at normal levels but more red blood cells were destroyed 3 h after the perfusion. The blood oxygen saturation of the perfusion group was maintained at 95% - 98%. NA⁺ and K⁺ concentrations were normal most of the time during perfusion but increased significantly at about 4 h. The Ca²⁺ concentration remained within the normal range at each period. Glucose levels were slightly higher than the baseline level. The pH of the perfusion solution was slightly lower at the beginning of perfusion, and then gradually increased to the normal level. The water content of brain tissue in the sub-low and docile perfusion group was 78.95% ± 0.39%, which was significantly higher than that in the control group (75.27% ± 0.55%, t = 10.49, p < 0.001), and the difference was statistically significant. Compared with the blank control group, the structure and morphology of pyramidal neurons in the prefrontal cortex and CA1 region of the hippocampal gyrus were similar, and their integrity was better. The structural integrity of granulosa neurons was destroyed and cell edema increased in the perfusion group compared with the blank control group. Immunofluorescence staining for glail fibrillary acidic protein and Iba1, markers of glial cells, revealed well-preserved cell structures in the perfusion group. While there were indications of abnormal cellular activity, the analysis showed no significant difference in axon thickness or integrity compared to the 1-h blank control group. CONCLUSIONS Mild hypothermic machine perfusion can improve ischemia and hypoxia injury of yorkshire brain tissue caused by traumatic blood loss and delay the necrosis and apoptosis of yorkshire brain tissue by continuous oxygen supply, maintaining ion homeostasis and reducing tissue metabolism level.
Animals ; Perfusion/methods* ; Disease Models, Animal ; Brain Injuries/etiology* ; Swine ; Male ; Hypothermia, Induced/methods*