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1.
Transplant Proc ; 48(4): 1288-91, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27320606

RESUMO

Cellular survival and death are at least partially regulated by the phosphorylation of proteins. A chaperon protein, 14-3-3ζ, regulates the activity of many proteins by covering the phosphorylation site within a 14-3-3 binding motif. Therefore, regulation of 14-3-3ζ activity may affect the fate of cells subjected to cold preservation and/or hypothermic oxygenated conditions. The present study assessed whether 14-3-3ζ protects cells from hypothermic oxygenation-induced injury and clarified its role in mitochondrial functions. Human renal tubular cell line HK-2 or 14-3-3ζ-overexpressed HK-2 (ζHK-2) cells were subjected to 72 hours of normoxic cold preservation in UW solution with or without antioxidants and hydroperoxides. Cellular death, adenosine triphosphate (ATP) content, and MTT catabolism were evaluated. Deferoxamine treatment reduced cellular death and augmented ATP content in both cell types. These indices were higher in ζHK-2, regardless of deferoxamine treatment. Exposure to hydroperoxides did not affect cellular death in either cell type, whereas hydroperoxide supplementation significantly reduced ATP content, except for low-dose hydrogen peroxide in HK-2 cells. MTT assay at normal state showed higher values in ζHK-2 cells, whereas it was impaired by hydroperoxides in both cell types. These results suggest that accumulation of hydroperoxides as a byproduct of the augmented oxidative phosphorylation by 14-3-3ζ overexpression causes mitochondrial dysfunction. In conclusion, despite possessing many potentially protective functions, 14-3-3ζ exacerbates cellular injury under hypothermic oxygenated conditions. 14-3-3ζ accelerates mitochondrial functions together with iron-dependent oxidative damage. Although further investigations are necessary, upregulation of 14-3-3ζ could be a method to maintain mitochondrial function under hypothermic oxygenated conditions, as shown in hypothermic machine preservation of renal grafts, when appropriate antioxidant treatment is administered.


Assuntos
Proteínas 14-3-3/fisiologia , Túbulos Renais/fisiologia , Proteínas 14-3-3/metabolismo , Adenosina/farmacologia , Alopurinol/farmacologia , Antioxidantes/farmacologia , Soluções Cardioplégicas/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Criopreservação/métodos , Desferroxamina/farmacologia , Glutationa/farmacologia , Humanos , Insulina/farmacologia , Túbulos Renais/citologia , Túbulos Renais/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Preservação de Órgãos/métodos , Soluções para Preservação de Órgãos/farmacologia , Fosforilação Oxidativa , Estresse Oxidativo/fisiologia , Rafinose/farmacologia , Sideróforos/farmacologia
2.
Transplant Proc ; 44(2): 373-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22410020

RESUMO

Because of the serious organ shortage in Japan, the use of extended criteria (EC) donors is inevitable to increase the number of deceased donors. However, the influence of this practice on recipient outcomes has not been clarified yet. We analyzed donor and recipient factors to determine whether those factors, especially from EC donors impacted early recipient outcomes. From February 1999 to January 2011, 100 deceased liver transplantations were performed in Japan, including 85 consecutive adult cases (age≥18 years) who were studied to evaluate whether 6 recipient and 16 donor factors affected 3-month (90-day) recipient survival. Upon univariate analysis, Model for End-stage Liver Disease (MELD) score≥25 (P=.018), donor age≥55 years (P=.040), and cold ischemia time (CIT)≥10 hours (P=.00013) significantly reduced 3-month survival. Multivariate analysis confirmed the independent contributions of, three adverse factors including MELD score≥25 (P=.0133, odds ratio [OR]=12.3, 95% confidence interval [CI]=1.7-90.3), donor age≥55 years (P=.013, OR=14.0, 95% CI=1.6-119.5), and CIT≥10 hours (P=.0024, OR=67.6, 95% CI=4.5-1024.9). Three-month recipient survivals with 0, 1, 2, and 3 positive factors were 100% (n=34), 94.4% (n=36), 53.8% (n=13), and 0% (n=2), respectively (P<.0001). In conclusion, to improve recipient short-term survivals, minimizing CIT is the first priority. In the long-term, we must promote deceased donation to reduce recipient MELD scores by shortening the waiting time, and revise the allocation system to minimize CIT by giving priority to the local area.


Assuntos
Seleção do Doador , Transplante de Fígado , Doadores de Tecidos/provisão & distribuição , Fatores Etários , Isquemia Fria/efeitos adversos , Feminino , Humanos , Japão , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Medição de Risco , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo , Obtenção de Tecidos e Órgãos , Resultado do Tratamento , Listas de Espera
3.
ASAIO J ; 42(5): M332-7, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8944901

RESUMO

An implantable rechargeable battery is one of the key technologies for totally implantable artificial hearts. The nickel-metal hydride (Ni-MH) battery is promising for its high energy density of 1.5-2.0 times that of a nickel-cadmium battery. In this study, the effects of pulsatile discharge loads on the operating time and cycle life of Ni-MH batteries at 39 degrees C were studied. Two battery cells (TH-3M, 1,200 mAh, phi 14.5 x 49 mm; Toshiba, Tokyo, Japan) in series were charge/discharge cycled at 39 degrees C using a charge current of 1CA (1,200 mA) and then were fully discharged to 1.0 V/cell under either pulsatile discharge loads, which mimicked a systole (1 A for 0.3 sec) and a diastole (0.4 A for 0.3 sec), or a non pulsatile discharge load equivalent to the average of the pulsatile loads (0.7 A). Each cycle life test was interrupted on the 482nd cycle under pulsatile load, and on the 423rd cycle under non pulsatile load, because of malfunction of each battery charger. The tests showed that the pulsatile discharge cells had significantly (p < 0.001) less operating time (74.0 +/- 7.15 min) throughout the test period (up to 482 days) compared to the cells under equivalent non pulsatile discharge loads (93.7 +/- 7.74 min). The pulsatile-discharged Ni-MH cells provide significantly less operating time than the constantly discharged cells; the Ni-MH battery has an operating time of over 78 min and a cycle life of almost 500 cycles at 39 degrees C. In conclusion, the Ni-MH battery is feasible as an implantable back-up battery for a totally implantable artificial heart system.


Assuntos
Eletrônica Médica/instrumentação , Coração Artificial , Estudos de Avaliação como Assunto , Humanos , Técnicas In Vitro , Níquel , Desenho de Prótese
4.
Pharmacology ; 53(2): 114-22, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8902876

RESUMO

The effects of various organic anions (2 mumol/100 g body weight) on biliary glutathione excretion were studied in rats. Bromosulfophthalein markedly inhibited glutathione excretion, whereas dibromosulfophthalein was a less potent inhibitor. Experiments with different bromosulfophthalein doses revealed that the extent of inhibition of glutathione excretion was related to the total bromosulfophthalein excretion. Indocyanine green also inhibited biliary glutathione excretion. Dinitrophenyl glutathione and pravastatin did not inhibit biliary glutathione excretion. These findings indicate the existence of several pathways of biliary excretion of organic anions and suggest that one of them is a pathway for biliary glutathione excretion.


Assuntos
Bile/metabolismo , Glutationa/metabolismo , Indicadores e Reagentes/farmacologia , Sulfobromoftaleína/análogos & derivados , Sulfobromoftaleína/farmacologia , Animais , Bile/efeitos dos fármacos , Indicadores e Reagentes/administração & dosagem , Injeções Intraperitoneais , Marcação por Isótopo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Espectrofotometria Ultravioleta , Sulfobromoftaleína/administração & dosagem
5.
Artif Organs ; 20(6): 497-502, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8817946

RESUMO

One of the key technologies required for rotary blood pumps is sealing of the motor shaft. A ferrofluidic seal was developed for an axial flow pump. The seal body was composed of a plastic magnet and two pole pieces. This seal was formed by injecting ferrofluid into the gap between the pole pieces and the motor shaft. To contain the ferrofluid in the seal and to minimize the possibility of ferrofluid making contact with blood, a shield with a small cavity was provided on the pole piece. Sealing pressure of the seal was measured. The sealing pressure was maintained at more than 23.3 kPa (175 mm Hg) for a motor speed up to 11,000 rpm. The specially designed ferrofluidic seal for sealing out liquids is useful for axial flow blood pumps.


Assuntos
Coração Auxiliar/normas , Velocidade do Fluxo Sanguíneo , Campos Eletromagnéticos , Polímeros , Pressão
8.
Hepatology ; 16(2): 365-71, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1639345

RESUMO

We previously reported that the human Y' bile acid binder, which has higher bile acid binding affinities than rat Y' binders (3 alpha-hydroxysteroid dehydrogenases), has dihydrodiol dehydrogenase activity and is different from 3 alpha-hydroxysteroid dehydrogenases. In this study, 3 alpha-hydroxysteroid dehydrogenases and 3 beta-hydroxysteroid dehydrogenase were purified from human liver, and bile acid binding affinities and enzyme kinetics of the 3 alpha-hydroxysteroid dehydrogenases were studied. On chromatofocusing of pooled Affigel blue fraction of the Y' fraction, three 3 alpha-hydroxysteroid dehydrogenase peaks eluted at pH 6.0, 5.7 and 5.4. These peaks did not bind bile acids, and further purification by hydroxyapatite-high-performance liquid chromatography gave pure 3 alpha-hydroxysteroid dehydrogenases with identical M(r) (36,000) having dihydrodiol dehydrogenase activity. 3 beta-Hydroxysteroid dehydrogenase was eluted together with Y' bile acid binder at pH 7.2 on chromatofocusing and was separated from Y' bile acid binder on hydroxyapatite-high-performance liquid chromatography as a pure protein with M(r) 32,000. The apparent Kms of 3 alpha-hydroxysteroid dehydrogenases were similar to those of rat enzymes. In conclusion, we purified human hepatic 3 alpha-hydroxysteroid dehydrogenases, which have similar characteristics to rat enzymes, but do not bind bile acids or reduce bile acid precursors. These data further support the importance of human bile acid binder in intracellular bile acid transport in the human liver.


Assuntos
3-Hidroxiesteroide Desidrogenases/isolamento & purificação , Citosol/enzimologia , Fígado/enzimologia , 3-alfa-Hidroxiesteroide Desidrogenase (B-Específica) , Ácidos e Sais Biliares/metabolismo , Humanos , Cinética
9.
Kyobu Geka ; 43(9): 754-6, 1990 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-2232399

RESUMO

The patients reported as double chambered right ventricle are mainly children. A 60-year-old woman had been pointed out for her systolic cardiac murmur without any symptom. She was admitted to our hospital for her gradual onset of fatigue, lassitude. Cardiac catheterization data revealed a 105 mmHg peak-to-peak gradient within the right ventricular cavity with normal pulmonary pressures [20/5 (12) mmHg]. Right ventricular end-diastolic pressure was 4 mmHg. Right ventriculogram demonstrated double chambered right ventricle. Electrocardiogram showed neither right ventricular hypertrophy nor upright T wave in V3R. In order to release intraventricular pressure gradient and her symptom, the anomalous muscle bundles were resected through both the right atrium and the pulmonary artery. Surgical repair without right ventriculotomy is suitable for such an elder patient with double chambered right ventricle whose ventricular function may decrease.


Assuntos
Ventrículos do Coração/anormalidades , Fatores Etários , Cateterismo Cardíaco , Eletrocardiografia , Feminino , Ventrículos do Coração/cirurgia , Humanos , Métodos , Pessoa de Meia-Idade
10.
Nihon Kyobu Geka Gakkai Zasshi ; 37(9): 1979-83, 1989 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-2600474

RESUMO

A 70-year-old man was successfully operated on A-C bypass for coronary triple vessel disease and replacement of abdominal aortic aneurysm. The two different procedures were performed simultaneously under cardio-pulmonary bypass. This simultaneous operation can provide benefits of shortening operating time and of clamping easily the abdominal aorta.


Assuntos
Aneurisma Aórtico/cirurgia , Ponte de Artéria Coronária , Doença das Coronárias/cirurgia , Idoso , Aorta Abdominal/cirurgia , Aneurisma Aórtico/complicações , Prótese Vascular , Doença das Coronárias/complicações , Humanos , Masculino
11.
Gan To Kagaku Ryoho ; 16(8 Pt 2): 2880-3, 1989 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-2506826

RESUMO

We report the complications and the results of intra-arterial infusion chemotherapy (IAIC) for liver metastases in colorectal cancer. Fifteen synchronous liver metastases and 11 metachronous liver metastases were treated from September 1986 to February 1989. Eight cases had H1 (metastases in one lobe only), 11 cases H2 (a few scattered metastases in both lobes) and 7 cases had H3 (numerous metastases in both lobes). Eight cases underwent hepatic resection and 20 cases were treated by IAIC with implantable reservoir. Incidence of complication was decreased from 75% to 17% by the improved technique of hepatic arterial catheter intubation. Median survival was 12 months, 20 months and 8 months, respectively. When used with MMC, the IAIC showed unsatisfactory results. We should therefore investigate possible use of alternative drugs, their optimum dosages, and the regimens for improved chemotherapy.


Assuntos
Neoplasias Colorretais/patologia , Neoplasias Hepáticas/tratamento farmacológico , Mitomicinas/administração & dosagem , Adulto , Idoso , Cateterismo/efeitos adversos , Cateterismo/métodos , Feminino , Artéria Hepática , Humanos , Bombas de Infusão , Infusões Intra-Arteriais/métodos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Mitomicina , Mitomicinas/uso terapêutico
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