BACKGROUND:Human embryonic stem cels exhibit self-renewal and multi-differentiation potential, and can differentiate into endothelial cels under certaininduction conditions.
OBJECTIVE:To explore induced conditions of the human embryonic stem cels differentiating into endothelial cels and to investigate the effect of vascular endothelial growth factors on theendothelial differentiation of human embryonic stem cels.
METHODS:After resuscitation,passage40 human embryonic stem cel lines H9 weresubjected to suspension culture to prepare embryos, and after 5-day culture,these cels werecultured in attachment medium to differentiate into embryoid bodies,folowed by induction with50 μg/L vascular endothelial growth factors. Passage 2 and 15 embryonic stem cels after induced differentiation weretaken for Dil-Ac-LDL uptake test and immunohistochemical staining, respectively.
RESULTS AND CONCLUSION:After 1-day culture, cord-like or polygonal monolayer cels around embryoid bodies showed bud-like andradialgrowth witharelative rapid speed merging into surrounding colonies; at 2-3 days, the number of suspension cels increased further, but the smal-round cels in the center began to die; at 5 days, embryoid bodies started to passage, and aggregated cels exhibited typical paving stone-like appearance. Moreover, some human embryonic cels after induced differentiation could actively takeupfluorescent labeled LDL,andred fluorescent particlesappeared.Additionaly, passage 15 embryonic stem cels after induced differentiation could express CD31 and FLK-1.These findings suggest that human embryonic stem cels induced by vascular endothelial growth factors can differentiate into endothelial cels.

ObjectiveTo verify the reliability of the mouse model of cerebral cortical microinfarct induced by two-photon microscopy and to explore its pathological changes.MethodsSeventeen male C57BL/6J mice were randomly divided into a microinfarct group (n=11) or a sham operation group (n=6).A thinned cranial window of 3 mm diameter was performed over the cerebral cortex with a high-speed micro-drill until the small blood vessels were clearly observed under a dissecting microscope.Then, a permanent single cortical penetrating arteriole occlusion was induced with a gradually enhanced ultrashort laser irradiation through the thinned cranial window with two-photon microscopy.At 7 days after modeling, the cerebral microinfarct volume was measured with HE staining, and the neuron loss, activation of glial cells and deposition of 3-nitrotyrosine were assessed using immunohistochemistry.ResultsThe target vessels of cerebral cortex in 8 (72.7%) mice were occluded and the microinfarcts formed in the microinfarct group, and the average microinfarct volume was 317.23±20.29 μm3.There were remarkable neuron loss and microglia infiltration in the infarcted core, a large number of reactive astrocytes surrounding the infarcted lesion, and massive deposition of 3-nitrotyrosine in the peri-infarct area.No infarcts were observed in the sham operation group.The deposition of 3-nitrotyrosine in the sham operation group was significantly less than that in the microinfarct group (8.00±1.48 vs.98.38±9.10;t=23.962, P<0.001).Conclusions The mouse model of cerebral cortical microinfarct induced by two-photon microscopy is reliable, and its histopathologic changes are consistent with the pathologic features of cerebral microinfarct.

Objective To investigate the effects and mechanisms of LINC00657 on oxidative glu-cose deprivation(OGD)-induced injury in mouse hippocampal neurons.Methods Mouse hippocam-pal neuron cell line HT22 was given OGD treatment to establish an injury model,with normally cul-tured HT22 cells as controls.The si-NC,si-LINC00657,microRNA(miR)-NC,and miR-224-3p mimics were transfected into HT22 cells,followed by OGD treatment.Co-transfection of si-LINC00657 and anti-miR-NC,or co-transfection of si-LINC00657 and anti-miR-224-3p,was performed in HT22 cells before OGD treatment.Real-time quantitative reverse transcription-polymerase chain reaction(qRT-PCR)was used to detect the relative expression levels of LINC00657 and miR-224-3p.CCK-8 assay and flow cytometry were used to detect cell viability and apoptosis rate,respectively.Kits were used to detect the activities of lactate dehydrogenase(LDH),superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),and the level of malondialdehyde(MDA).Dual-luciferase reporter gene assay was used to detect the effect of miR-224-3p overexpression on the luciferase activity of wild-type LINC00657 vector(WT-LINC00657)and mutant LINC00657 vector(MUT-LINC00657).Results Compared with controls,the expression of LINC00657 was upregulated and the expression of miR-224-3p was downregulated in OGD-induced HT22 cells(P＜0.05).Compared with trans-fection of si-NC or miR-NC,transfection of si-LINC00657 or miR-224-3p mimics resulted in in-creased cell viability,SOD activity,and GSH-Px activity,as well as decreased apoptosis rate,LDH activity,and MDA level(P＜0.05).Overexpression of miR-224-3p reduced the luciferase activity of WT-LINC00657(P＜0.05).Compared with cells co-transfected with si-LINC00657 and anti-miR-NC,cells co-transfected with si-LINC00657 and anti-miR-224-3p showed decreased cell viabili-ty,increased apoptosis rate,increased LDH activity and MDA level,and decreased SOD and GSH-Px activities(P＜0.05).Conclusion Interference with LINC00657 can promote cell proliferation,inhibit apoptosis and oxidative stress response by upregulating miR-224-3p,thereby alleviating OGD-induced injury in mouse hippocampal neurons.

Objective To investigate the effects and mechanisms of LINC00657 on oxidative glu-cose deprivation(OGD)-induced injury in mouse hippocampal neurons.Methods Mouse hippocam-pal neuron cell line HT22 was given OGD treatment to establish an injury model,with normally cul-tured HT22 cells as controls.The si-NC,si-LINC00657,microRNA(miR)-NC,and miR-224-3p mimics were transfected into HT22 cells,followed by OGD treatment.Co-transfection of si-LINC00657 and anti-miR-NC,or co-transfection of si-LINC00657 and anti-miR-224-3p,was performed in HT22 cells before OGD treatment.Real-time quantitative reverse transcription-polymerase chain reaction(qRT-PCR)was used to detect the relative expression levels of LINC00657 and miR-224-3p.CCK-8 assay and flow cytometry were used to detect cell viability and apoptosis rate,respectively.Kits were used to detect the activities of lactate dehydrogenase(LDH),superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),and the level of malondialdehyde(MDA).Dual-luciferase reporter gene assay was used to detect the effect of miR-224-3p overexpression on the luciferase activity of wild-type LINC00657 vector(WT-LINC00657)and mutant LINC00657 vector(MUT-LINC00657).Results Compared with controls,the expression of LINC00657 was upregulated and the expression of miR-224-3p was downregulated in OGD-induced HT22 cells(P＜0.05).Compared with trans-fection of si-NC or miR-NC,transfection of si-LINC00657 or miR-224-3p mimics resulted in in-creased cell viability,SOD activity,and GSH-Px activity,as well as decreased apoptosis rate,LDH activity,and MDA level(P＜0.05).Overexpression of miR-224-3p reduced the luciferase activity of WT-LINC00657(P＜0.05).Compared with cells co-transfected with si-LINC00657 and anti-miR-NC,cells co-transfected with si-LINC00657 and anti-miR-224-3p showed decreased cell viabili-ty,increased apoptosis rate,increased LDH activity and MDA level,and decreased SOD and GSH-Px activities(P＜0.05).Conclusion Interference with LINC00657 can promote cell proliferation,inhibit apoptosis and oxidative stress response by upregulating miR-224-3p,thereby alleviating OGD-induced injury in mouse hippocampal neurons.

Objective:To observe the effect of high-flow nasal cannula oxygen therapy (HFNC) in patients with chronic obstructive pulmonary disease (COPD) and mild hypercapnia, and to evaluate the early predictive ability of physiological parameters in these patients.Methods:A retrospective cohort study was conducted based on Medical Information Mart for Intensive Care-Ⅳ (MIMIC-Ⅳ) updated in September 2020 and the data of adult patients with COPD and mild hypercapnia [45 mmHg (1 mmHg = 0.133 kPa) < arterial partial pressure of carbon dioxide (PaCO 2)≤ 60 mmHg] from 2008 to 2019 were collected. These patients were assigned to the HFNC group or non-invasive ventilation (NIV) group according to whether they received HFNC or NIV. Baseline data such as gender, age, body mass index (BMI), simplified acute physiology scoreⅡ (SAPSⅡ), Charlson comorbidity index (CCI) and physiological parameters were collected. A propensity score matching was conducted according to the baseline data of the HFNC group patients. The 48-hour and 28-day intubation rates, 28-day mortality, length of intensive care unit (ICU) stay, the length of hospital stay, and the changes in physiological parameters within 48 hours after treatment were compared between the two groups. The receiver operating characteristic curve (ROC curve) was drawn and the ratio of heart rate over pulse oxygen saturation (HR/SpO 2) and ROX index [SpO 2 / (inhaled oxygen concentration, FiO 2×respiratory rate, RR)] were analyzed to predict the 24-hour and 48-hour intubation rates. Results:A total of 524 520 inpatient records were screened and 153 patients were included, while 37 patients in the HFNC group and 116 patients in NIV group. There were 31 patients in the HFNC group and 84 patients in the NIV group remained after propensity score matching according to the baseline data. There were no significant differences in the baseline data of gender, age, BMI, SAPSⅡ, CCI score, physiological parameters and prognosis data except the length of ICU stay. The length of ICU stay in HFNC group was significant longer than that of the NIV group [days: 4.6 (3.1, 10.0) vs. 3.1 (1.6, 5.8), P < 0.05]. HR and RR at 40- 48 hours were significantly lower than those at 0-8 hours after treatment only in the HFNC group [HR (bpm): 84.1±12.2 vs. 91.1±16.4, RR (times/min): 19.8±4.9 vs. 21.6±4.1, both P < 0.05]. Both in the HFNC group and NIV group the pH increased (7.42±0.08 vs. 7.36±0.05 and 7.41±0.06 vs. 7.36±0.05, both P < 0.05) and PaCO 2 decreased significantly [mmHg: 46.3 (39.5, 51.0) vs. 49.8 (45.5, 54.0) and 46.0 (40.5, 51.5) vs. 49.5 (45.5, 55.3), both P < 0.05]. The HR, PaO 2 were higher in the HFNC group than those in the HFNC group at 40-48 hours after treatment [HR (bpm): 91.1±15.4 vs. 84.1±12.2, PaO 2 (mmHg): 99.5 (86.0, 132.3) vs. 85.8 (76.5, 118.0), both P < 0.05], PaO 2/FiO 2 were lower in the HFNC group than that in the HFNC group at 40-48 hours after treatment [mmHg: 223.8 (216.5, 285.0) vs. 278.0 (212.3, 306.0), P < 0.05]. Both HR/SpO 2 and ROX index at 4 hours after treatment had predictive value for 24-hour and 48-hour intubation in the HFNC group. The areas under ROC curve (AUC) of HR/SpO 2 at 4 hours after treatment in the HFNC group were larger than those of ROX index for predicting 24-hour and 48-hour intubation (24-hour: 0.649 vs. 0.574, 48-hour: 0.692 vs. 0.581, both P < 0.01); the 95% confidence interval (95% CI) of 4 hours HR/SpO 2 and for ROX index predicting 24 hours and 48 hours intubation were 0.497-0.780, 0.567-0.799, 0.450-0.694 and 0.454-0.716, respectively. The high sensitivity of HR/SpO 2 and ROX index in predicting 24-hour and 48-hour intubation were 84.6%, 92.9%, 88.2% and 94.4%, respectively, and the low specificity were 52.3%, 23.7%, 54.7% and 29.6%, respectively. Conclusions:HFNC can be used in COPD patients with mild hypercapnia, but it cannot replace NIV. The accuracy of ROX index at 4 hours after HFNC treatment in predicting intubation in COPD patients with mild hypercapnia is poor.

Objective:To evaluate the diagnostic accuracy of a noninvasive physiological parameter-based early sepsis screening model for elderly patients in comparison to the systemic inflammatory response syndrome(SIRS)and quick sequential organ failure assessment(qSOFA)scores.Methods:A retrospective study was conducted using data from the Medical Information Mart for Intensive Care Ⅳ(MIMIC-Ⅳ)database.The study focused on patients who were admitted to the intensive care unit(ICU)within 24 hours and were categorized into septic and non-septic groups based on the presence or absence of sepsis.Baseline data and patient outcomes were recorded.Additionally, the SIRS score and qSOFA scores within 24 hours of ICU admission were calculated.Physiological parameters that showed statistical significance in the univariate analysis included respiratory rate, heart rate, level of consciousness, body temperature, systolic blood pressure, and urine output.These parameters were then included in Logistic regression models.The specificity and sensitivity of the regression model for sepsis screening were calculated, and receiver operating characteristic(ROC)curves were plotted.The areas under the ROC curves(AUCs)of the screening model, SIRS, and qSOFA scoring systems were compared.Results:A total of 53 150 ICU hospitalization records were screened, and 23 681 patients with infection or suspected infection within 24 hours were included.Among them, 18 277 patients had sepsis.The 28-day mortality rate for septic patients was higher compared to non-septic patients(13.5% vs.5.1%, χ2=285.131, P<0.001).The baseline data within 24 hours showed significant differences between the two groups in terms of heart rate, respiratory rate, body temperature, state of consciousness, 24-hour urine output, and systolic blood pressure(all P<0.001).These variables were included in the regression equation: ∑β iX i=2.055+ 0.285(temperature: 0/1)+ 0.172(respiratory rate: 0/1)+ 0.073(heart rate: 0/1)+ 1.204(mental status: 0/1)-0.022(systolic blood pressure)+ 0.227(classification of urine output: 0/1/2), P=1/[1+ EXP(-∑β iX i)].The regression model diagnosed sepsis ROC area in young and middle-aged patients as 0.726(95% CI: 0.718 to 0.735), which was significantly higher than the SIRS score(0.585, 95% CI: 0.576 to 0.595)and the qSOFA score(0.676, 95% CI: 0.667 to 0.685)(both P<0.001).In elderly patients, the regression model diagnosed sepsis ROC area as 0.671(95% CI: 0.663 to 0.679), which was also significantly higher than the SIRS score(0.572, 95% CI: 0.563 to 0.580)and the qSOFA score(0.631, 95% CI: 0.623 to 0.639)(both P<0.001). Conclusions:The early sepsis diagnosis model, which utilizes noninvasive physiological parameters, has shown higher accuracy when compared to the SIRS and qSOFA scores.However, it is important to note that its accuracy is lower in elderly patients as compared to young and middle-aged patients.This indicates the necessity for further optimization of the model in order to improve its performance in diagnosing sepsis in the elderly.

Lipid Droplets/metabolism* ; Bacteria ; Lipid Metabolism