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排序方式: 共有763条查询结果,搜索用时 18 毫秒
51.
An In Vivo Autotransplant Model of Renal Preservation: Cold Storage Versus Machine Perfusion in the Prevention of Ischemia/Reperfusion Injury 总被引:2,自引:0,他引:2
Gaetano La Manna †Diletta Conte †Maria Laura Cappuccilli †‡Bruno Nardo Francesca D'Addio †‡Lorenza Puviani Giorgia Comai †Francesca Bianchi ‡Riccardo Bertelli †Nicole Lanci Gabriele Donati Maria Piera Scolari ‡Alessandro Faenza Sergio Stefoni 《Artificial organs》2009,33(7):565-570
There is increasing proof that organ preservation by machine perfusion is able to limit ischemia/reperfusion injury in kidney transplantation. This study was designed to compare the efficiency in hypothermic organ preservation by machine perfusion or cold storage in an animal model of kidney autotransplantation.
Twelve pigs underwent left nephrectomy after warm ischemic time; the organs were preserved in machine perfusion ( n = 6) or cold storage ( n = 6) and then autotransplanted with immediate contralateral nephrectomy. The following parameters were compared between the two groups of animals: hematological and urine indexes of renal function, blood/gas analysis values, histological features, tissue adenosine-5'-triphosphate (ATP) content, perforin gene expression in kidney biopsies, and organ weight changes were compared before and after preservation.
The amount of cellular ATP was significantly higher in organs preserved by machine perfusion; moreover, the study of apoptosis induction revealed an enhanced perforin expression in the kidneys, which underwent simple hypothermic preservation compared to the machine-preserved ones. Organ weight was significantly decreased after cold storage, but it remained quite stable for machine-perfused kidneys.
The present model seems to suggest that organ preservation by hypothermic machine perfusion is able to better control cellular impairment in comparison with cold storage. 相似文献
Twelve pigs underwent left nephrectomy after warm ischemic time; the organs were preserved in machine perfusion ( n = 6) or cold storage ( n = 6) and then autotransplanted with immediate contralateral nephrectomy. The following parameters were compared between the two groups of animals: hematological and urine indexes of renal function, blood/gas analysis values, histological features, tissue adenosine-5'-triphosphate (ATP) content, perforin gene expression in kidney biopsies, and organ weight changes were compared before and after preservation.
The amount of cellular ATP was significantly higher in organs preserved by machine perfusion; moreover, the study of apoptosis induction revealed an enhanced perforin expression in the kidneys, which underwent simple hypothermic preservation compared to the machine-preserved ones. Organ weight was significantly decreased after cold storage, but it remained quite stable for machine-perfused kidneys.
The present model seems to suggest that organ preservation by hypothermic machine perfusion is able to better control cellular impairment in comparison with cold storage. 相似文献
52.
Zehadin Gashi Roberta Censi Ledjan Malaj Roberto Gobetto Matteo Mozzicafreddo Mauro Angeletti Admir Masic Piera Di Martino 《Journal of pharmaceutical sciences》2009,98(11):4216-4228
The present work aims at the application of several methods to explain differences in the physical interaction of some aryl propionic acid derivatives (ibuprofen [IBP], ketoprofen [KET], flurbiprofen [FLU], naproxen [NAP], fenbufen [FEN]) with poly(vinylpyrrolidone) (PVP) K30, stored together at 298 ± 0.5 K and 22% RH. X-ray powder diffractometry and 13C-solid state NMR demonstrated that IBP was able to strongly interact with the polymer, while weak interaction was observed for KET, FLU, NAP, and the least for FEN. The interaction of comelted drug and PVP was studied by differential scanning calorimetry by applying the Gordon–Taylor equation, which revealed that small molar drug volumes may favour the drug diffusion through the PVP amorphous chains increasing the polymer free volume and decreasing the mixture Tg. The molecular docking study revealed that intermolecular energy is mainly due to the contribution of van der Waals energy component, causing the differences among the drugs, and is related to the drug–PVP surface contact area in the complex formed. Solid-state kinetic study demonstrated that IBP molecules are involved in a three-dimensional diffusion mechanism within the polymer favoured by its low molar volume that reduces molecular hindrance, and by the weakness of its crystal lattice, which facilitates crystallinity loss and stabilisation of the amorphous phase. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:4216–4228, 2009 相似文献
53.
Nasuti C Gabbianelli R Falcioni ML Di Stefano A Sozio P Cantalamessa F 《Toxicology》2007,229(3):194-205
Pyrethroids are a class of insecticides involved in different neurological disorders. They cross the blood-brain barrier and exert their effect on dopaminergic system, contributing to the burden of oxidative stress in Parkinson's disease through several pathways. The aim of the present study was to evaluate the effect of neonatal exposition to permethrin and cypermethrin (1/10 of DL(50)) in rats from the eighth to the fifteenth day of life. Open-field studies showed increased spontaneous locomotor activity in the groups treated with permethrin and the one treated with cypermethrin, while a higher number of center entries and time spent in the center was observed for the cypermethrin-treated group. Lower dopamine and higher homovanillic acid levels were measured in the striatum from both treated groups. A reduction of blood glutathione peroxidase content was measured, while no change in blood superoxide dismutase was observed. Carbonyl group formation increased in striatum, but not in erythrocytes. Lipid peroxidation occurred in erythrocytes, but not in striatum. No changes in fluidity at different depths of plasma membrane were measured in striatum or erythrocytes. The activation of monocyte NADPH oxidase by phorbol esters (PMA) shows that superoxide anion production was reduced in the pyrethroid-treated groups compared to the control group. Our studies suggest that neonatal exposition to permethrin or cypermethrin induces long-lasting effects after developmental exposure giving changes in open-field behaviors, striatal monoamine level, and increased oxidative stress. Although the action of pyrethroids on various target cells is different, a preferential interaction with the extracellular side of plasma membrane proteins can be observed. 相似文献
54.
Scala Daniela Mucherino Sara Wirth Francesca Orlando Valentina Polidori Piera Faggiano Maria Ernestina Iovine Daniela Saturnino Paola Cattel Francesco Costantini Alberto Giua Corrado Makoul Gregory Azzopardi Lilian M. Menditto Enrica 《International journal of clinical pharmacy》2022,44(4):1037-1045
International Journal of Clinical Pharmacy - Effective communication strategies in health care help to enhance patient empowerment and improve clinical outcomes. Adapt the original Communication... 相似文献
55.
56.
Takemoto SK Arns W Bunnapradist S Garrison LP Guirado L Kalo Z Oniscu G Opelz G Scolari MP Stefoni S Yaqoob M Brennan DC 《Transplantation》2008,86(1):18-25
Transplantation offers a unique opportunity to demonstrate the complementary roles of randomized controlled trials and outcome research. The surgery and collaboration necessary for the transplant procedure makes randomization and blinding difficult. Because essentially every recipient is included in a transplant registry, sampling bias is minimized. Regulatory agencies generally do not consider outcomes research when assessing efficacy of new drugs or medical interventions. This workgroup summary examines the suitability of outcomes research to complement results of randomized controlled trials and related issues: efficacy versus effectiveness, internal versus external validity, data types, limitations, and analysis methodologies. Many advances in outcomes research have been pioneered in transplantation. A case is made for regulatory and reimbursement authorities to use outcomes research when making efficacy, effectiveness, and coverage decisions in transplantation. 相似文献
57.
Andrea Ferrari Michela Casanova Filippo Spreafico Roberto Luksch Monica Terenziani Graziella Cefalo Maura Massimino Lorenza Gandola Piera Navarria Franca Fossati-Bellani 《Pediatric hematology and oncology》1999,16(5):415-421
A retrospective observational study was performed on a series of 12 consecutive pediatric patients treated over a 20-year period at the Istituto Nazionale Tumori, Milano. Conservative surgery was the treatment of choice in all patients; radical excision was obtained at diagnosis in 9 cases and after primary chemotherapy in 1 case. Five patients were subjected to surgery alone, and one to postoperative radiotherapy. After a median follow-up of 11 years (range 1-20), all the patients were alive without evidence of disease, 11 in first complete remisson, and 1 after local relapse. In agreement with other reports, the authors underline the unquestionable pivotal role of radical surgery in the treatment of liposarcoma. The high proportion of resectable tumors accounts for the excellent survival of the patients in this study. The role of both adjuvant chemotherapy and radiotherapy is uncertain and awaits multicentric cooperative prospective studies. 相似文献
58.
59.
Raha D Nehar S Paswan B Rebuffat P Neri G Naskar R Kumari K Raza B Rao NV Macchi C Sen NS Nussdorfer GG Ahmad MF 《International journal of molecular medicine》2007,20(1):91-95
Insulin-like growth factor (IGF)-I is a ubiquitously synthesized peptide that, along with IGF-II, acts via the IGF-R type I receptor. IGF-I and its receptor are expressed in the adrenal gland of humans and bovines, the secretion of which they seem to stimulate. As in humans and cows, the main glucocorticoid hormone secreted by guinea-pig adrenals is cortisol, and hence we have studied the adrenocortical effects of IGF-I in this species. In vivo experiments showed that prolonged IGF-I administration raised the plasma concentration of cortisol in both normal and dexamethasone/captopril-treated guinea pigs, thereby ruling out the possibility that IGF-I may act by activating the hypothalamic-pituitary-adrenal axis and the renin-angiotensin system. In vitro experiments demonstrated that IGF-I enhanced basal, but not maximally agonist [ACTH and angiotensin-II (Ang-II)]-stimulated, cortisol secretion from freshly dispersed guinea-pig inner adrenocortical cells. The IGF-I immuno-neutralization suppressed the IGF-I secretagogue effect, without altering the cortisol response to both ACTH and Ang-II. IGF-I raised cyclic-AMP and inositol triphosphate release from dispersed guinea-pig cells, and the effect was reversed by the adenylate cyclase inhibitor SQ-22536 and the phospholipase-C (PLC) inhibitor U-73122. SQ-22536, U-73122, the protein kinase (PK) A inhibitor H-89 and the PKC inhibitor calphostin-C decreased by approximately 50% the cortisol response of dispersed cells to IGF-I, and the combined exposure to SQ-22536 and U-73122 abolished it. We conclude that IGF-I stimulates glucocorticoid secretion from guinea-pig adrenocortical cells, acting via selective receptors coupled to both the adenylate cyclase/PKA- and PLC/PKC-dependent signaling cascades. 相似文献
60.
Luccardini C Yakovlev A Gaillard S van 't Hoff M Alberola AP Mallet JM Parak WJ Feltz A Oheim M 《Journal of biomedicine & biotechnology》2007,2007(7):68963
Semiconductor nanocrystals (NCs) are increasingly being used as photoluminescen markers in biological imaging. Their brightness, large Stokes shift, and high photostability compared to organic fluorophores permit the exploration of biological phenomena at the single-molecule scale with superior temporal resolution and spatial precision. NCs have predominantly been used as extracellular markers for tagging and tracking membrane proteins. Successful internalization and intracellular labelling with NCs have been demonstrated for both fixed immunolabelled and live cells. However, the precise localization and subcellular compartment labelled are less clear. Generally, live cell studies are limited by the requirement of fairly invasive protocols for loading NCs and the relatively large size of NCs compared to the cellular machinery, along with the subsequent sequestration of NCs in endosomal/lysosomal compartments. For long-period observation the potential cytotoxicity of cytoplasmically loaded NCs must be evaluated. This review focuses on the challenges of intracellular uses of NCs. 相似文献