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1.
目的:观察肝再生刺激因子(HSS)及表皮生长因子(EGF)对肝细胞增殖再生作用合适剂量及其联合效应。并推测HSS作用时相。方法:以^3HTdR掺入法检测细胞DNA增殖;体外原代大鼠肝细胞培养不同时间加入HSS,MTT法检测细胞生长状况。结果与结论:1.HSS(≤100μg/ml)和EGF(≤100ng/ml)对肝衍生细胞均有显著刺激作用(P<0.01),并存在剂量关系,但剂量过大,刺激作用反而下降。2.HSS、EGF存在协同作用,原代肝细胞、肝癌细胞株(SMMC.7721、BEL.7402)体外培养48h后,经(^3H)TdR掺入法检测cpm值分别为各自对照组的5.94,298和3.36倍。3.体外培养原代大鼠肝细胞,于贴壁后0h,20h加入HSS其刺激作用较40h组显著,提示HSS可能主要作用于肝细胞再生G1/S期。  相似文献   

2.
目的探讨重组大鼠肝再生增强因子(rrALR)对体外培养的肾小管上皮细胞增殖及凋亡的影响。方法将体外培养的人肾小管上皮细胞株(HK2)分组,分别加入不同浓度的庆大霉素(GM)或(和)m~LR,^3H-胸腺嘧啶核苷(^3H-TdR)掺入法检测HK2细胞的增殖:吖啶橙/溴乙啶(AO/EB)染色和钙磷脂结合蛋白/碘化丙啶(annexin V/PI)双标记流式细胞术检测上述各组HK2细胞的凋亡。结果(1)rrALR对常规培养条件下的HK2细胞有直接的促增殖作用。并具有量效关系(在25ng/ml~50μg/ml的浓度范围内逐渐增强,P〈0.01)和时效关系(培养12h即有该作用,48h达到高峰,以后逐渐下降,P〈0.05);(2)rrALR能够促进GM损伤后的HK2细胞增殖,有明显剂量依赖性(P〈0.05);(3)rrALR呈剂量依赖性抑制GM诱导的HK2细胞凋亡(P〈0.01)。结论rrALR能够促进体外常规培养和GM损伤后的肾小管上皮细胞增殖.抑制GM诱导的小管上皮细胞凋亡,提示ALR可能对小管上皮细胞的中毒性损伤有改善作用。  相似文献   

3.
骨髓间充质干细胞定向分化肝细胞及肝内移植研究   总被引:7,自引:2,他引:7  
目的 观察体外诱导骨髓问充质干细胞分化及肝纤维化形成环境中移植情况。方法 首先行骨髓间充质干细胞提取、分离和培养,加入肝细胞生长因子(HGF,20μg/L)和表皮生长因子(EGF,1.5mg/L)诱导定向分化。肝纤维化形成的大鼠随机分成2组,每组10只。使用5-溴脱氧尿苷(BrdU)标记诱导的骨髓间充质干细胞,经门静脉向肝纤维化形成的SD大鼠肝脏移植,对照组用BrdU标记未经诱导的骨髓间充质干细胞。2周后通过免疫组织化学方法检测大鼠肝脏标记细胞的分布及BrdU^+/ALB^+细胞数量。结果 体外诱导骨髓间充质干细胞定向分化的细胞CK8及ALB表达阳性。移植2周后大鼠肝脏均可检测到BrdU标记细胞,与对照组相比诱导后骨髓问充质干细胞组BrdU^+/ALB^+细胞数较多,差异有统计学意义(P〈0.05)。结论 经体外诱导骨髓间充质干细胞能分化为肝细胞,移植在大鼠肝纤维化形成环境中,白蛋白表达细胞数更多。  相似文献   

4.
目的 探讨肝星状细胞(hepatic stellate cells,HSCs)在大鼠肝部分切除术后对肝损伤修复的影响.方法 体外实验部分:将大鼠肝星状细胞(HSCs)与大鼠肝细胞系(BRL-3A)共培养,CCK-8比色法检测细胞增殖情况;ELISA法检测培养肝星状细胞上清液中细胞因子,即肝细胞生长因子(hepatic growth factor,HGF)、胰岛素样生长因子(insulin growth factor,IGF)、表皮细胞生长因子(epidermal growth factor,EGF)、转化生长因子-α(transfactor growth factor-α,TGF-α)含量.体内实验部分;将45只260 ~330 g健康雄性SD大鼠随机分为三组:正常组(生理盐水组)、对照组(肝星状细胞培养液组)、实验组(肝星状细胞培养上清液组).各组分别于肝大部切除术后第3、7、12天取血清检测肝功能情况并计算肝再生指数;HE染色切片显微镜下观察肝脏病理结构改变情况;免疫组织化学染色法检测增殖细胞核抗原(proliferating cell nucleus antigen,PCNA)、平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)、甲胎蛋白(a1pha feta1 protein,AFP)及白蛋白(albumin,ALB)的表达情况.结果 ①CCK-8法检测肝星状细胞能促进肝细胞增殖(P<0.05);②上清液较培养液中细胞因子HGF、TGF-α含量多,差别有统计学意义(P< 0.05);③实验组肝再生指数比对照组大,差别具有统计学意义(P<0.05);④实验组大鼠AST随着时间的推移,较对照组下降明显,差别有统计学意义(P<0.05);⑤实验组PCNA表达量较正常组、对照组增多,差别有统计学意义(P< 0.05);⑥平滑肌肌动蛋白、白蛋白、甲胎蛋白三组间差别不显著(P> 0.05).结论 ①体外肝星状细胞能促进肝细胞增殖;②肝星状细胞培养上清液能促进大鼠肝部分切除术后肝再生,其分泌的多种细胞因子在肝损伤再生修复中起了重要作用.  相似文献   

5.
目的 利用原代培养肝细胞,研究鹅脱氧胆酸损害肝细胞机制。方法 SD大鼠肝细胞原代短期培养,分别加入不同浓度的甘氨鹅氧胆酸(glycochenodeoxycholate,GCDC)后,流式细胞术检测凋亡细胞和坏死肝细胞的比例;抽提DNA电泳,涂片后生物素-dUTP标记凋亡细胞。胆总管结扎SD大鼠肝组织免疫组织化学染色检测Bcl-2基因表达。肝细胞与100μmol/L GCDC和不同浓度的果糖培养后,  相似文献   

6.
目的 探讨大鼠骨髓基质干细胞向肝细胞分化后体外标记方法及移植肝细胞的肝内组织学表现。方法 分离大鼠骨髓基质细胞,在体外诱导分化为成熟肝细胞。将5-溴脱氧尿嘧啶核苷(BrdU)掺入后的肝细胞移植入已行部分肝切除大鼠体内,分别应用免疫组织化学和免疫荧光方法观察受体肝脏内移植细胞的形态和功能。结果分化成熟肝细胞在BrdU掺入培养后细胞核染色可见特异性棕褐色标记;肝细胞移植后肝组织切片BrdU染色可定位移植细胞;白蛋白抗体染色显示移植细胞具有功能活性。结论 骨髓基质干细胞分化来源的肝细胞移植后形态功能稳定,是进行肝细胞移植的理想细胞来源。  相似文献   

7.
表皮生长因子和雌激素对肝脏DNA合成的影响初步研究   总被引:2,自引:0,他引:2  
目的 通过比较EGF,EGF-雌激素以及雌激素对原代培养肝细胞DNA合成的影响,探讨用EGF治疗肝细胞损伤的可能性。方法 用大鼠获得单个肝细胞悬液,随机分成EGF组、雌激素组、EGF-雌激素组及对照组进行细胞培养,3天后测量每组Tdk掺入量。结果 EGF组及EGF-雌激素的^3H-Tdk掺入量分别为对照组的2.1倍及3.4倍(P<0.01),雌激素亦有轻度促进DNA合成作用(P<0.05)。结论EGF在雌激素协同下能成倍地增加肝细胞DNA合成。  相似文献   

8.
目的探讨表达hTERT蛋白的重组腺病毒rAd-hTERT感染体外原代培养的肝细胞后对其增殖情况的影响。方法将表达hTERT蛋白的重组腺病毒rAd-hTERT感染体外原代培养的肝细胞。同时设空载体对照组及空白对照组。通过定量PCR及Western-blot检测基因在细胞中的表达情况;MTT法观察其对细胞增殖的影响;采用流式细胞术检测rAd-hTERT对细胞周期和凋亡的影响。结果(1)以50MOIrAd-hTERT感染肝细胞可明显促进其生长增殖,但不会引起细胞毒性作用。(2)定量PCR在转录水平检测rAd-hTERT感染后的细胞中hTERT表达量明显增加。(3)Western-blot在蛋白水平验证rAd-hTERT感染后的细胞中hTERT蛋白的表达及其蛋白活性。(4)流式细胞DNA含量分析显示,rAdhTERT可引起肝细胞周期S+62/M期增加,并抑制细胞的凋亡。结论rAd-hTERT在体外能有效促进原代肝细胞的生长。与阴性对照比较,同期生长的肝细胞S+62/M期细胞增加,凋亡细胞减少(P〈0.05),并未引起细胞的不典型增生表现。  相似文献   

9.
目的:探讨原代培养的大鼠肾小球系膜细胞血管内皮生长因子(vascular endothelial growth factor,VEGF)的表达及转化生长因子-β1(transforming growth factor-β1,TGF-β1)对其表达的影响。方法:采用RT-PCR和Westernblot方法检测大鼠原代培养的肾小球系膜细胞VEGF表达及不同浓度、不同时间的TGF-β1刺激对VEGF表达的作用。结果:原代培养的大鼠肾小球系膜细胞表达VEGF164、120mRNA,TGF-β1呈时间依赖性增加其表达,在12h表达最高,分别为刺激前3.17、2.925倍,有统计学差异(P〈0.001)。在剂量反应曲线上,2ng/ml TGF-β1刺激作用最强,VEGF164、120mRNA表达分别为未刺激组的2.82、2.45倍,有统计学差异(P〈0.001)。与VEGF mRNA表达一致,大鼠原代肾小球系膜细胞仅见VEGF164蛋白表达,2ng/ml TGF-β1呈时间依赖性的增加VEGF 164蛋白表达,24h达高峰,为刺激前的2.37倍。结论:促进肾小球系膜细胞VEGF表达可能是TGF-β1介导肾脏损害发生、发展的机制之一。  相似文献   

10.
目的通过比较EGF,EGF-雌激素以及雌激素对原代培养肝细胞DNA合成的影响,探讨用EGF治疗肝细胞损伤的可能性.方法用大鼠获得单个肝细胞悬液,随机分成EGF组、雌激素组、EGF-雌激素组及对照组进行细胞培养,3天后测量每组Tdk掺入量.结果EGF组及EGF-雌激素的3H-Tdk掺入量分别为对照组的2.1倍及3.4倍(P<0.01),雌激素亦有轻度促进DNA合成作用(P<0.05).结论EGF在雌激素协同下能成倍地增加肝细胞DNA合成.  相似文献   

11.
Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI2) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI2), TXB2 (stabile metabolite of thromboxane A2) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI2 release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB2 (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI2 release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A2, presumably contributing to hemodynamic stability within 30 min after MT.  相似文献   

12.
Don Dame 《Artificial organs》1996,20(5):613-617
Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.  相似文献   

13.
Background: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1.
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably.  相似文献   

14.
Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.  相似文献   

15.
Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H2O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg−1 followed by 0.15 mg · kg−1 · h−1, n=8) or verapamil (0.1 mg · kg−1 followed by 0.3 mg · kg−1 · h−1, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.  相似文献   

16.
Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.  相似文献   

17.
Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.  相似文献   

18.
Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg?1 i. v. or midazolam 0.05 mg · kg?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg?1 i. v. and 32 μg · kg?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg?1. The mean ED50s, calculated from dose-response curves, were 5.4 mg · kg?1, 3.9 μg · kg?1 and 0.4 mg · kg?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg?1 i. v. or midazolam 0.05 mg · kg?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg?1 and 8 μg · kg?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.  相似文献   

19.
Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg?1 · min?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min?1 · m?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO2I) and oxygen consumption index (VO2I) were also significantly increased in the dopexamine group (DO2I: from 416±91 to 717±110 ml/m2 · m2; VO2I: from 98±25 to 157±22 ml/m2 · m2), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.  相似文献   

20.
A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.  相似文献   

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