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Objective To investigate whether the overexpression of neurogenin 3 ( Ngn3 ) can promote the induced differentiation of human umbilical cord mesenchymal stem cells ( HUCMSCs) into insulin-producing cells (IPGs). Methods HUCMSCs were isolated and cultured, identified by flow cytometry, and the differentiation potential was identified by adipogenesis and osteogenesis induction. HUCMSCs were induced into IPCs in different stages, including a low glucose induction stage and a high glucose induction stage. The experiment was divided into two groups, the control group was induced by the above scheme, while the experimental group was additionally infected the lentivirus overexpression vector carrying the target gene Ngn3 on the 6th day of the same induction process. After induction, the changes of cell structure were observed by electron microscope ; mRNA and protein was collected and Real-time PCR and Western blotting were used to compare the expressions of insulin and musculoaponeurotic fibrosarcoma oncogene homolog A Mafa in the two groups ; medium supernatant was collected and C-peptide content was determined by ELISA. Results HUCMSCs were successfully isolated with positive expression of CD 105 and CD90 and negative expression of CD34 and CD45, which had adipogenic and osteogenic differentiation ability. Then, HUCMSCs were induced into IPCs by stage induction, and the cells expressed Mafa and insulin positively. Ngn3 was overexpressed in the experimental group during the induction. After induction, electron microscopy showed that the cell structure was more mature in the experimental group. The expression levels of insulin and Mafa in the experimental group were significantly higher than those in the control group. During the induction process, the amount of C-peptide secreted by the experimental group was higher than that of the control group. Conclusion Lentivirus-mediated Ngn3 overexpression improves the differentiation efficiency of HUCMSCs into IPCs.
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Objective:To compare the effects of phenoxybenzamine and doxazosin on intraoperative hemodynamics in patients with normotensive pheochromocytoma.Methods:Perioperative data of patients who underwent surgery for normotensive pheochromocytoma in Peking University First Hospital from January 1, 2004 to December 31, 2017 were collected.Patients were divided into phenoxybenzamine group and doxazosin group according to the type of preoperative α-blockade.The primary endpoint was intraoperative hemodynamic fluctuations.Secondary endpoints included postoperative circulatory support, complications, mortality, and etc.Results:Sixty-one patients were included in the study, with 24 cases in phenoxybenzamine group and 37 cases in doxazosin group.There was no significant difference in the area under the curve of intraoperative blood pressure fluctuation between the two groups ( P>0.05). The area under the curve of intraoperative heart rate >110 bpm was significantly greater in phenoxybenzamine group than in doxazosin group ( P<0.05). There was no significant difference in the secondary endpoints between the two groups ( P>0.05). Conclusion:The effect of preoperative administration of doxazosin or phenoxybenzamine on blood pressure fluctuation has no significantly statistical difference in patients with normotensive pheochromocytoma, and the patients took phenoxybenzamine preoperatively have an increased risk of intraoperative tachycardia.
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Objective To evaluate the risk factors for intraoperative hemodynamic instability (HI) in patients with adrenal incident pheochromocytoma.Methods Perioperative clinical parameters of patients undergoing surgery for adrenal incident pheochromocytoma at the First Hospital of Peking University from January 2001 to July 2018 were analyzed.There were 39 males and 41 females,with mean age of 45.1 years (13-76 years old).The median tumor length was 5.1 cm (1.5-14.0 cm),with 25 cases (31.3％) on the left side,55 cases (68.8％) on the right side.There were 37 cases combined with coronary heart disease or diabetes or BMI≥24 kg/m2.Patients were divided into hemodynamic instability (HI group) and hemodynamic stability group (HS group) by whether intraoperative hemodynamic instability occurred.The differences of demographic characteristics and clinical parameters between the two groups were compared.Logistic regression analysis was done for seeking the risk factors for hemodynamic instability during surgery.Results There were 54 cases (67.5％) in the HS group and 26 cases (32.5％) in the HI group.Univariate analysis showed that there was no significant difference in age [(44.06 ± 13.58) years old vs.(47.35 ± 16.11) years old],combined with coronary heart disease or diabetes or BMI≥24 kg/m2 [50.0％(27/54) vs.38.5％ (10/26)],tumor long diameter [median 5.0 cm(1.5-14.0 cm) vs.6.0cm(1.5-13.5 cm)],tumor location [left:29.6％ (16/54) vs.34.6％ (9/26)],preoperative catecholamine test positive [44.4％ (20/45) vs.50.0％ (10/20)],open surgery [27.8％ (15/54) vs.34.6％ (9/26)]and preoperative non-alpha blockers[13.0％ (7/54) vs.30.8％ (8/26)] between HS group and HI group (P ＞ 0.05).Further logistic regression analysis was used to analyze the risk factors of intraoperative hemodynamic instability.Multivariate analysis found that patients who preoperative non-alpha blockers before surgery were independent risk factor for HI (OR =4.574,95 ％ CI 1.273-16.432,P =0.020).Conclusions Preoperative non-alpha blocker in patients with adrenal incidental pheochromocytoma could be independent risk factor for intraoperative hemodynamic instability.Therefore,it is recommended that patients with adrenal incidental tumors,especially those who fail to rule out pheochromocytoma,take preoperative alpha blockers.
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Objective To investigate the relationship between preoperative albumin level and postoperative acute kidney injury(AKI)following off-pump coronary artery bypass(OPCAB)surgery;to confirm albumin cut-off value associated with AKI. Method This was a retrospective cohort study. data from patients who accepted OPCAB surgery in last two years in our hospital and AKI was diagnosed according to KIDGO-AKI criteria. Results Generalized additive model and multivariable logistic regression analysis have shown that the higher preoperative albumin level is related with the lower the incidence of AKI after OPCAB surgery. By generalized additive model,multivariable logistic regression analysis and ROC curve,we confirmed the albumin cut-off value associated with AKI between 39~40 g/L. Conclusion For patients undergoing OPCAB surgery,the higher preoperative albumin level ,the lower the incidence of AKI. In order to reduce the incidence of AKI in OPCAB surgery patients,preoperative albumin level higher than 40 g/L should be maintained.
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The objectives of this study were to investigate the effects of veratridine (VER) on persistent sodium current (I(Na.P)), Na(+)/Ca(2+) exchange current (I(NCX)), calcium transients and the action potential (AP) in rabbit ventricular myocytes, and to explore the mechanism in intracellular calcium overload and myocardial contraction enhancement by using whole-cell patch clamp recording technique, visual motion edge detection system, intracellular calcium measurement system and multi-channel physiological signal acquisition and processing system. The results showed that I(Na.P) and reverse I(NCX) in ventricular myocytes were obviously increased after giving 10, 20 μmol/L VER, with the current density of I(Na.P) increasing from (-0.22 ± 0.12) to (-0.61 ± 0.13) and (-2.15 ± 0.14) pA/pF (P < 0.01, n = 10) at -20 mV, and that of reverse I(NCX) increasing from (1.62 ± 0.12) to (2.19 ± 0.09) and (2.58 ± 0.11) pA/pF (P < 0.05, n = 10) at +50 mV. After adding 4 μmol/L tetrodotoxin (TTX), current density of I(Na.P) and reverse I(NCX) returned to (-0.07 ± 0.14) and (1.69 ± 0.15) pA/pF (P < 0.05, n = 10). Another specific blocker of I(Na.P), ranolazine (RAN), could obviously inhibit VER-increased I(Na.P) and reverse I(NCX). After giving 2.5 μmol/L VER, the maximal contraction rate of ventricular myocytes increased from (-0.91 ± 0.29) to (-1.53 ± 0.29) μm/s (P < 0.01, n = 7), the amplitude of contraction increased from (0.10 ± 0.04) to (0.16 ± 0.04) μm (P < 0.05, n = 7), and the baseline of calcium transients (diastolic calcium concentration) increased from (1.21 ± 0.08) to (1.37 ± 0.12) (P < 0.05, n = 7). After adding 2 μmol/L TTX, the maximal contraction rate and amplitude of ventricular myocytes decreased to (-0.86 ± 0.24) μm/s and (0.09 ± 0.03) μm (P < 0.01, n = 7) respectively. And the baseline of calcium transients reduced to (1.17 ± 0.09) (P < 0.05, n = 7). VER (20 μmol/L) could extend action potential duration at 50% repolarization (APD(50)) and at 90% repolarization (APD(90)) in ventricular myocytes from (123.18 ± 23.70) to (271.90 ± 32.81) and from (146.94 ± 24.15) to (429.79 ± 32.04) ms (P < 0.01, n = 6) respectively. Early afterdepolarizations (EADs) appeared in 3 out of the 6 cases. After adding 4 μmol/L TTX, APD(50) and APD(90) were reduced to (99.07 ± 22.81) and (163.84 ± 26.06) ms (P < 0.01, n = 6) respectively, and EADs disappeared accordingly in 3 cases. It could be suggested that: (1) As a specific agonist of the I(Na.P), VER could result in I(Na.P) increase and intracellular Na(+) overload, and subsequently intracellular Ca(2+) overload with the increase of reverse I(NCX). (2) The VER-increased I(Na.P) could further extend the action potential duration (APD) and induce EADs. (3) TTX could restrain the abnormal VER-induced changes of the above-mentioned indexes, indicating that these abnormal changes were caused by the increase of I(Na.P). Based on this study, it is concluded that as the I(Na.P) agonist, VER can enhance reverse I(NCX) by increasing I(Na.P), leading to intracellular Ca(2+) overload and APD abnormal extension.
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Animals , Rabbits , Acetanilides , Pharmacology , Action Potentials , Calcium , Metabolism , Myocardial Contraction , Myocytes, Cardiac , Cell Biology , Patch-Clamp Techniques , Piperazines , Pharmacology , Ranolazine , Sodium-Calcium Exchanger , Metabolism , Tetrodotoxin , Pharmacology , Veratridine , PharmacologyABSTRACT
Objectiye To investigate the expression of regulated on activation, normal T-cell expressed and secreted (RANTES) and occluding in brain, and investigate the role of expression of RANTES in the change of blood-brain barrier permeability of rats with acute pancreatitis. Methods 49 Sprague-Dawley rats were randomly divided into 7 groups according to random number table, including sham-operated group (SO) , acute edematous pancreatitis (AEP) 3, 6 h group and acute necrotizing pancreatitis (ANP) 3, 6, 12 and 24 h group. AEP and ANP were induced by retrograde injection of 0. 5% and 5% sodium taurocholate, respectively. RT-PCR, Western blot, and immunohistochemistry methods were performed to assess the expression of RANTES and occludin mRNA and protein in brain tissue. Results The RANTES mRNA expressions in SO, AEP 3, 6 h, ANP 3, 6, 12, 24 h group were 0, 0, 0, 0.36±0.05, 0.47±0.04, 0.65±0.05, 0.83±0.07, respectively; The RANTES protein expressions were 0, 0, 0, 0.42±0. 03, 0. 57±0.04,0.78±0.08, 1.05±0.08, respectively; the values in ANP group were significantly lower than those in SO group and AEP group (P<0.01). The occludin mRNA expressions were 1.21±0.07,1.17±0.07, 1.15±0.08,0.84±0.07,0.77±0.05,0.64±0.09,0.56±0.09, respectively, the occludin protein expressions were 1.18 ±0.08, 1. 16 ±0. 10, 1. 11 ±0. 10, 0. 90 ±0. 03, 0. 65 ±0."05, 0.57 ±0.05, 0.48 ±0.05, respectively, the values in ANP group were significantly lower than those in SO group and AEP group (P< 0.01). The expression of RANTES was positively related to the pancreatic pathologic score (r = 0. 936,P< 0. 001) ; the expression of occluding was negatively related to the pancreatic pathologic score (r = - 0. 943, P < 0.001). The expression of RANTES was negatively related to the expression of occluding (r = -0. 943, P <0. 001). Conclusions The expression of RANTES was progressively increased in the brain tissue in rats with ANP, while the expression of occluding was progressively decreased; RANTES may play an important role in the change of blood-brain barrier permeability via down-regulating the expression of occluding.
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This article introduces cryosurgery devices, cryopreservation devices, some cryogenic freezing methods in medicine and the recent progress about cryotherapy technology.