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101.
Inhibition of autophagy increases apoptosis during re‐warming after cold storage in renal tubular epithelial cells 下载免费PDF全文
Swati Jain Daniel Keys Trevor Nydam Robert J. Plenter Charles L. Edelstein Alkesh Jani 《Transplant international》2015,28(2):214-223
Prolonged cold storage and re‐warming (CS/REW) of kidneys are risk factors for delayed graft function (DGF). Studies in renal tubular epithelial cells (RTECs) have determined apoptosis and autophagy in models of either cold storage (CS) or re‐warming alone. The effect of both cold storage and re‐warming on apoptosis and autophagy, in RTECS is not known and is relevant to DGF as the kidney is subjected to both CS and re‐warming. We hypothesized that CS/REW of RTECs would induce autophagy that protects against apoptosis. In CS/REW, there was increased autophagic flux of RTECs. Autophagy inhibition using an Atg5 siRNA resulted in increased cleaved caspase‐3 and increased apoptotic cells (on both morphology and annexin V staining) during CS/REW. The effect of autophagy inhibition on necrosis in RTECs is unknown. There were increased necrosis and caspase‐1, a mediator of necrosis, during CS/REW, and the Atg5 siRNA had no effect on necrosis and caspase‐1. In a kidney transplant model, there was an increase in LC3 II, a marker of autophagy, in kidneys transplanted after cold storage. In summary, autophagic flux is increased during CS/REW. Autophagy inhibition resulted in increased cleaved caspase‐3 and increased apoptosis during CS/REW without an effect on necrosis or caspase‐1. In conclusion, autophagy inhibition in RTECs after CS/REW induces apoptotic cell death and may be deleterious as a therapy to decrease DGF. 相似文献
102.
Liisa E. Paavola Anne M. Remes Marika J. Harila Tarja T. Varho Tapio T. Korhonen Kari Majamaa 《Journal of Neurodevelopmental Disorders》2015,7(1)
Background
Salla disease (SD) is a rare lysosomal storage disorder leading to severe intellectual disability. SD belongs to the Finnish disease heritage, and it is caused by mutations in the SLC17A5 gene. The aim of the study was to investigate the course of neurocognitive features of SD patients in a long-term follow-up.Methods
Neuropsychological and neurological investigations were carried out on 24 SD patients, aged 16–65 years, 13 years after a similar examination.Results
The survival analysis showed excess mortality among patients with SD after the age of 30 years. The course of the disease was progressive, but follow-up of SD patients revealed that motor skills improved till the age of 20 years, while mental abilities improved in most patients till 40 years of age. Verbal comprehension skills did not diminish during the follow-up, but productive speech deteriorated because of dyspraxia and dysarthria. Motor deficits were marked. Ataxia was prominent in childhood, but it was replaced by athetotic movements during the teens. Spasticity became more obvious with age especially in severely disabled SD patients.Conclusions
Younger SD patients performed better in almost every task measuring mental abilities that then seem to remain fairly constant till early sixties. Thus, the results indicate better prognosis in cognitive skills than earlier assumed. There is an apparent decline in motor skills after the age of 20 years. The early neurocognitive development predicts the later course of motor and cognitive development. 相似文献103.
104.
JY Nagata TF Rocha‐Lima BP Gomes CC Ferraz AA Zaia FJ Souza‐Filho A De Jesus‐Soares 《Australian dental journal》2015,60(3):416-420
Immature avulsed teeth are not usually treated with pulp revascularization because of the possibility of complications. However, this therapy has shown success in the treatment of immature teeth with periapical lesions. This report describes the case of an immature replanted tooth that was successfully treated by pulp revascularization. An 8‐year‐old boy suffered avulsion on his maxillary left lateral incisor. The tooth showed incomplete root development and was replanted after 30 minutes. After diagnosis, revascularization therapy was performed by irrigating the root canal and applying a calcium hydroxide paste and 2% chlorhexidine gel for 21 days. In the second session, the intracanal dressing was removed and a blood clot was stimulated up to the cervical third of the root canal. Mineral trioxide aggregate was placed as a cervical barrier at the entrance of the root canal and the crown was restored. During the follow‐up period, periapical repair, apical closure and calcification in the apical 4 mm of the root canal was observed. An avulsed immature tooth replanted after a brief extra‐alveolar period and maintained in a viable storage medium may be treated with revascularization. 相似文献
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107.
目的 探讨标本在室温保存时,不同放置时间对血小板功能检测仪PL-11结果的影响.方法 采集我院2012级学员队20位健康学员及2013年我院门诊20位服用氯吡格雷和阿司匹林的冠心病患者肘静脉枸橼酸钠抗凝全血,应用PL-11分别在采血后不同保存时间点(2 h、4 h、8 h)测定不同血小板活化诱导剂诱导的血小板聚集率.结果 健康组:以花生四烯酸(arachidonic acid,AA)为血小板活化诱导剂时,2 h、4 h、8 h的放置时间对血小板聚集功能未产生影响(P>0.05);二磷酸腺苷(adenosine di-phosphate,ADP)为诱导剂时,血小板聚集率在4 h明显降低(P<0.01),8 h时已经降低至4.3%(P<0.01);胶原(collagen,Col)诱导的血小板聚集率在采血后4 h时较2 h明显降低(P<0.01),但与8 h差异无统计学意义(P>0.05).服用抗血小板药物组:AA诱导的血小板聚集率2 h、4 h、8 h两两差异均无统计学意义(P>0.05),ADP诱导的血小板聚集率在4 h时明显降低(P<0.01),4 h与8 h差异无统计学意义(P>0.05),Col诱导的血小板聚集率在8 h后出现明显降低(P<0.01).结论 枸橼酸盐抗凝血标本采集后放置时间对PL-11血小板功能检测存在影响,在检测健康人组或已服用双联抗血小板药物患者组时,AA诱导血小板聚集受时间影响较小,ADP与胶原诱导血小板聚集时随着标本放置时间延长,血小板聚集率降低.结合凝血功能检测对枸橼酸盐抗凝血的要求,PL-11检测血小板功能时,AA诱导聚集可在采血后4 h内完成,ADP与胶原诱导应在采血后2 h内完成. 相似文献
108.
Bhawna Chandravanshi Anandh Dhanushkodi Ramesh Bhonde 《The review of diabetic studies : RDS》2014,11(3):267-278
BACKGROUND: Poor recovery of islets upon cryopreservation is the main hurdle in islet banking. Pancreatic islets have a poor antioxidative defense mechanism, and exposure of islets to low temperature leads to oxidative stress. AIM: We aimed to investigate whether known compounds such as metformin, γ aminobutyric acid (GABA), docosahexanoic acid (DHA), or eicosapentaenoic acid (EPA) alone or in combination are capable of reducing oxidative stress for better islet recovery upon storage at suboptimal temperatures. METHODS: Islets isolated from mouse pancreas were stored at low temperature (4°C) for 15 days and at ultralow temperature (-196°C) for 30 days with or without additives. After revival from cold storage, islets were assessed by using three methods: (1) specificity by dithizone (DTZ), (2) viability by fluorescein diacetate/propidium iodide (FDA/PI) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetra-zolium bromide (MTT) assay, and (3) functionality by glucose-stimulated insulin secretion (GSIS). The oxidative status of the islets stored at suboptimal temperatures was determined by both intracellular free radical release (fluorometric analysis) and lipid peroxidation (enzymatic determination). RESULTS: Supplementation with additives led to an improvement in islet survival upon storage at suboptimal temperatures, without depletion of insulin secretory activity, which was comparable to that of controls. The additives acted as cryoprotectants and antioxidants as revealed by high recovery of viable islets and reduction in total reactive oxygen species (ROS) and malonidealdehyde (MDA), respectively. CONCLUSIONS: Our results demonstrate for the first time that supplementation with EPA, DHA, and metformin may lead to higher islet recovery from -196°C storage, enabling proper islet banking. 相似文献
109.
《Digestive and liver disease》2020,52(4):359-367
Lysosomal storage diseases (LSDs) are a heterogeneous group of inherited disorders caused by loss-of-function mutations in genes encoding for lysosomal enzymes/proteins. The consequence is a progressive accumulation of substrates in these intracellular organelles, resulting in cellular and tissue damage. The overall incidence is about 1/8000 live births, but is likely underestimated. LSDs are chronic progressive multi-systemic disorders, generally presenting with visceromegaly, and involvement of the central nervous system, eyes, the skeleton, and the respiratory and cardiovascular systems. The age at onset and phenotypic expression are highly variable, according to the specific enzymatic defect and tissues involved, the residual activity, and the disease-causing genotype. Enzyme-replacement therapies and substrate-reduction therapies have recently become available, leading to the improvement in symptoms, disease progression and quality of life of affected individuals. Liver involvement and hepatosplenomegaly are frequent features of LSDs and a hallmark of adult-onset forms, frequently leading to medical attention. LSDs should therefore be considered in the differential diagnosis of liver disease with organomegaly. The present document will provide a short overview of adult-onset LSDs with hepatic involvement, highlighting the specificities and systemic manifestations of the ones most frequently encountered in clinical practice, which may hint at the correct diagnosis and the appropriate treatment. 相似文献
110.
The extraordinary properties of shape memory NiTi alloy are combined with the inherent viscoelastic behavior of a silicon elastomer. NiTi wires are incorporated in a silicon elastomer matrix. Benefits include features as electrical/thermal conductivity, reinforcement along with enhanced damping performance and flexibility. To gain more insight of this composite, a comprehensive dynamic thermomechanical analysis is performed and the temperature- as well as frequency-dependent storage modulus and the mechanical loss factor are obtained. The analyses are realized for the composite and single components. Moreover, the models to express the examined properties and their temperature along with the frequency dependencies are also presented. 相似文献