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51.
Jürgen Treckmann Manfred Nagelschmidt Thomas Minor Fuat Saner Stefano Saad Andreas Paul 《Cryobiology》2009,59(1):19-23
Objectives
Especially for preservation of marginal donor organs, machine perfusion (MP) and retrograde oxygen persufflation (ROP) are alternatives to cold storage (CS). Using a porcine kidney autotransplantation model we compared metabolic and morphologic effects of CS, ROP, and MP on kidneys exposed to warm ischemia.Methods
Kidneys of 21 pigs were exposed in situ to warm ischemia for 60 min. The kidneys were randomly allocated to three experimental groups, each receiving a 4-h treatment of either cold storage, machine perfusion, or retrograde oxygen persufflation. Tissue samples were examined for malondialdehyde and histological changes. Daily blood samples were examined for creatinine levels.Results
Seven days after transplantation, the plasma creatinine levels in the CS and MP groups were still significantly elevated above the baseline values. In the ROP group, all animals exhibited nearly normal creatinine levels. Malondialdehyde, an indicator of lipidperoxidation, was dramatically increased in the machine perfused kidneys on day 7, whereas the malondialdehyde levels in the other two groups were near normal values. The MP kidneys exhibited the most striking histological changes.Conclusion
Though MP has been well introduced in organ transplantation, in our opinion, it must still be optimized and standardized. It is necessary to clarify questions such as whether there is a need for oxygenation during perfusion, the length of perfusion, the impact of pressure, and the effects of additional scavengers. The results of the present study suggest the reconsideration of the ROP-technique for the preservation of predamaged donor grafts especially of NHBD and further studies, comparing MP and ROP upon long term preservation are strongly encouraged. 相似文献52.
在成年狗身上制备右侧孤离颈动脉窦,借助灌流装置用饱和氧的任氏液对其进行灌流。灌流压为搏动性的。通过改变每搏泵出量、灌流管道的阻力和弹性来调节灌流压及其变化速率。用多导生理记录仪同步记录股动脉血压、窦内灌流压及其变化速率。本文主要观察窦内压的变化速率对降压反射的影响。在8只狗身上共进行了93次实验。结果表明,在窦内压相同的情况下,灌流压的上升速率愈快,降压效应愈明显,而其下降速率则无显著作用。已有资料证明搏动性窦内压所引起的降压效应较非搏动性压力更为明显。由此可见,狗的颈动脉窦压力感受器不仅对搏动性压力而且对其上升的变化速率也很敏感。 相似文献
53.
Minmin Huang Entezar Mehrabi Nasab Seyyed Shamsadin Athari 《Saudi Journal of Biological Sciences》2021,28(12):6957-6962
Asthma is a complicated lung disease, which has increased morbidity and mortality rates in worldwide. There is an overlap between asthma pathophysiology and mitochondrial dysfunction and MSCs may have regulatory effect on mitochondrial dysfunction and treats asthma. Therefore, immune-modulatory effect of MSCs and mitochondrial signaling pathways in asthma was studied.After culturing of MSCs and producing asthma animal model, the mice were treated with MSCs via IV via IT. BALf's eosinophil Counting, The levels of IL-4, −5, −13, −25, –33, INF-γ, Cys-LT, LTB4, LTC4, mitochondria genes expression of COX-1, COX-2, ND1, Nrf2, Cytb were measured and lung histopathological study were done.BALf's eosinophils, the levels of IL-4, −5, −13, −25, –33, LTB4, LTC4, Cys-LT, the mitochondria genes expression (COX-1, COX-2, Cytb and ND-1), perivascular and peribronchial inflammation, mucus hyper-production and hyperplasia of the goblet cell in pathological study were significantly decreased in MSCs-treated asthma mice and reverse trend was found about Nrf-2 gene expression, IFN-γ level and ratio of the INF-γ/IL-4.MSC therapy can control inflammation, immune-inflammatory factors in asthma and mitochondrial related genes, and prevent asthma immune-pathology. 相似文献
54.
Wen Yuan Chung Amar M. Eltweri John Isherwood Jonathan Haqq Seok Ling Ong Gianpiero Gravante David M. Lloyd Matthew S. Metcalfe Ashley R. Dennison 《Journal of visualized experiments : JoVE》2013,(82)
The use of ex vivo perfused models can mimic the physiological conditions of the liver for short periods, but to maintain normal homeostasis for an extended perfusion period is challenging. We have added the kidney to our previous ex vivo perfused liver experiment model to reproduce a more accurate physiological state for prolonged experiments without using live animals. Five intact livers and kidneys were retrieved post-mortem from sacrificed pigs on different days and perfused for a minimum of 6 hr. Hourly arterial blood gases were obtained to analyze pH, lactate, glucose and renal parameters. The primary endpoint was to investigate the effect of adding one kidney to the model on the acid base balance, glucose, and electrolyte levels. The result of this liver-kidney experiment was compared to the results of five previous liver only perfusion models. In summary, with the addition of one kidney to the ex vivo liver circuit, hyperglycemia and metabolic acidosis were improved. In addition this model reproduces the physiological and metabolic responses of the liver sufficiently accurately to obviate the need for the use of live animals. The ex vivo liver-kidney perfusion model can be used as an alternative method in organ specific studies. It provides a disconnection from numerous systemic influences and allows specific and accurate adjustments of arterial and venous pressures and flow. 相似文献
55.
The serum-free medium MDSS2 (Merten et al., 1994), was used for cultivating Vero cells as well as for producing poliovirus (Sabin type 1) in static and in perfused micro-carrier cultures. At slightly different growth rates of 0.0120/h and 0.0106/h, respectively, static cultures in serum-containing (SCM) and serum-free (SFM) medium produced titers of 106.75 and 106.67 TCID50 per 50 μl; signifying a specific productivity of 0.89 and 1.07 TCID50/c. Serum-free bioreactor cultures of Vero cells on DEAE-dextran microcarriers at 6.25 g/l produced cell densities of about 1.5×106c/ml. After infection with virus (multiplicity of infection (MOI) 0.1–0.3) titers of about 6.3×108 TCID50/ml were obtained, signifying an average specific productivity of 7.1 TCID50/c.h. Although these values were 4 and 2 fold, respectively, higher than in classical resum-based production processes (Montagnon et al. Dev. biol. Stand. 1981, 47, 55), a reference culture, for which cell growth was done in SCM and only virus production was done in SFM, produced 2×109 TCID/ml with an average specific virus production rate of 18.9 TCID50/c.h. The differences between the fully serum-free and our reference process were mainly due to physiological differences of cells grown in SCM and SFM and also due to strongly modified consumption kinetics after virus infection leading to limitations of one or several essential medium compounds, like glucose and amino acids. Avoiding these limitations by increasing the residual concentration of glucose, glutamine, histidine, and SH-amino acids, led to specific virus production rates (of about 17.9 TCID59/c.h.) comparable to those found in the reference virus production process. The optimisation of the production of the poliovirus (Sabin 1) will be described with respect to the modification of the medium composition. This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
56.
Elza van Deel Yanto Ridwan J. Nicole van Vliet Sasha Belenkov Jeroen Essers 《Journal of visualized experiments : JoVE》2016,(108)
The use of Micro-Computed Tomography (MicroCT) for in vivo studies of small animals as models of human disease has risen tremendously due to the fact that MicroCT provides quantitative high-resolution three-dimensional (3D) anatomical data non-destructively and longitudinally. Most importantly, with the development of a novel preclinical iodinated contrast agent called eXIA160, functional and metabolic assessment of the heart became possible. However, prior to the advent of commercial MicroCT scanners equipped with X-ray flat-panel detector technology and easy-to-use cardio-respiratory gating, preclinical studies of cardiovascular disease (CVD) in small animals required a MicroCT technologist with advanced skills, and thus were impractical for widespread implementation. The goal of this work is to provide a practical guide to the use of the high-speed Quantum FX MicroCT system for comprehensive determination of myocardial global and regional function along with assessment of myocardial perfusion, metabolism and viability in healthy mice and in a cardiac ischemia mouse model induced by permanent occlusion of the left anterior descending coronary artery (LAD). 相似文献
57.
Accurate cell settling velocity determination is critical for perfusion culture using a gravity settler for cell retention. We have developed a simple apparatus (a settling column) for measuring settling velocity and have validated the procedure with 15-μm polystyrene particles with known physical properties. The measured settling velocity of the polystyrene particles is within 4% of the value obtained using the traditional Stokes' law approach. The settling velocities of three hybridoma cell lines were measured, resulting in up to twofold variation among cell lines, and the values decreased as the cell culture aged. The settling velocities of the nonviable cells were 33-50% less than the corresponding viable cells. The significant variation of settling velocities among cell populations and growth phases confirms the necessity of routine measurement of this property during long-term perfusion culture. 相似文献
58.
应用快速灌注色谱系统首次从经Cd2+诱导的柱状田头菇(茶薪菇)Agrocybecylindracea(DC.:Fr:)R.Maoire菌丝体中分离得到一种镉结合蛋白。通过SephadexG-75凝胶过滤层析,原子吸收光谱分析(AAS),巯基含量测定及紫外吸收光谱分析表明这种镉结合蛋白具有金属硫蛋白(metallothionein,MT)的理化性质:即分子量为6kDa、每分子MT含18个半胱氨酸残基并结合7个镉原子、具有镉硫金属簇的特征紫外吸收光谱,初步鉴定为茶薪菇Cd-MT。 相似文献
59.
本文采用体重２００±２０ｇ健康雄性Ｗｉｓｔａｒ大鼠,随机分为平原冻伤（ＦＮ）组、急性缺氧冻伤（ＦＡＨ）组和缺氧习服缺氧冻伤（ＦＨＡＣ）组,实验观察了大鼠右后肢重度冻伤前后各组大鼠双后肢皮肤微循环灌流量的改变。结果表明,平原冻伤使大鼠双后肢微循环灌流量明显减少,提示局部重度冻伤对微循环的影响不只局限于冻区也涉及到对侧肢体。冷冻前ＦＡＨ组大鼠微循环灌流量已明显低于ＦＮ组,表明急性缺氧时血容量进行代偿性的再分配,使微循环灌流量减少;ＦＡＨ组大鼠冻后双后肢微循环灌流量的改变结果提示急性缺氧可加重其冻伤对微循环的损伤程度。ＦＨＡＣ组大鼠冻前微循环灌流量非常明显地低于正常对照,也明显低于急性缺氧对照,表明缺氧习服可造成微循环障碍;ＦＨＡＣ组大鼠冻肢微循环灌流量非常明显地低于ＦＮ组,提示缺氧习服加重高原冻伤引起的微循环障碍。 相似文献
60.
K. Akiyama T.L. Gluckman A. Terhakopian P.M. Jinadasa S. Narayan S. Singaswamy B. Massey III R.J. Bing 《Tissue & cell》1997,29(6):733-743
We report the appearance of apoptotic cells in experimental myocardial infarction (rabbit heart) in in situ and in vitro preparations. Apoptosis was recognized by intravital staining with Hoechst 33342 (Ho342), by nick-end labeling (TUNEL) and by DNA laddering. A steady rise in the relative number of apoptotic cardiomyocytes (apoptotic index) was noted in in situ preparations. Apoptosis was first noted 6 h after the onset of ischemia with its highest value occurring after 72 h. Apoptotic nuclei were absent in remote areas of the left and right ventricles. Apoptotic nuclei within the infarcted area showed diminished intensity of Ho342 fluorescence. Three days after ischemia, a border zone adjacent to the infarcted area consisting of apoptotic macrophages was recognized. A novel finding was the appearance of apoptotic cardiomyocytes in the isolated perfused ischemic heart. Occurring as early as 50 min after the onset of ischemia, a high apoptotic index was present adjacent to the ligature placed around the coronary artery. This observation provides the opportunity to selectively examine factors leading to apoptosis in the ischemic heart under controlled experimental conditions. 相似文献