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1.
J Phys Condens Matter ; 31(1): 015501, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30499454

RESUMO

We present a comprehensive spectroscopic study of C[Formula: see text] point-group symmetry sites in Sm[Formula: see text]:CaF[Formula: see text]/SrF[Formula: see text] codoped with either NaF or LiF. Data includes electron paramagnetic resonance measurements of Zeeman and hyperfine interactions for the ground state, as well as site-selective excitation and fluorescence spectroscopy up to the [Formula: see text]G[Formula: see text] multiplet. Inclusion of the EPR data allowed us to determine unique crystal-field parameters. The parameters provide information about the geometry of the sites and the nature of the interactions between the Sm[Formula: see text] dopant and the alkaline earth co-dopant.

2.
J Nutr Health Aging ; 20(2): 185-91, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26812515

RESUMO

OBJECTIVE: To investigate the effects of nutritional intervention with resistance training on skeletal muscle mass in elderly patients with disabilities in a convalescent rehabilitation setting. DESIGN: A randomized controlled trial. (UMIN Clinical Trials Registry ID: UMIN000006238). SETTING: A rehabilitation hospital. PARTICIPANTS: 39 elderly patients with decreased skeletal muscle mass in an inpatient convalescence rehabilitation unit. INTERVENTIONS: A combination of resistance training plus nutritional supplementation (R/N group) or resistance training alone (R group). The training and supplementation were conducted essentially from the patient's admission to discharge (2-6 months). OUTCOME MEASURES: The patients were evaluated at the time of admission and at the end of the intervention for skeletal muscle mass (calf circumference [CC] as a primary outcome, and arm circumference [AC]), hand grip strength (HG), Mini-Nutritional Assessment-Short Form (MNA®-SF) score, serum albumin level (Alb), body mass index (BMI), and activities of daily living (ADL) as represented by the Barthel Index (BI) score. RESULTS: Significant treatment effects were seen for CC, AC, BI, Alb in the R/N group compared to the R group. A mean treatment effect of 3.2 (95%CI: 2.0-4.4) was seen in CC, 1.4 (95%CI: 0.8-2.1) was seen in AC, 11.2 (95%CI: 0.5-21.8) was seen in BI, 0.3 (95%CI: 0.1-0.5) was seen in Alb. CONCLUSION: The results of this study suggest that nutritional intervention added to resistance training during convalescent rehabilitation may improve skeletal muscle mass and activities of daily living.


Assuntos
Atividades Cotidianas , Convalescença , Suplementos Nutricionais , Músculo Esquelético , Treinamento Resistido , Idoso , Idoso de 80 Anos ou mais , Braço , Índice de Massa Corporal , Feminino , Força da Mão , Hospitalização , Humanos , Perna (Membro) , Masculino , Albumina Sérica/metabolismo
3.
J Phys Condens Matter ; 18(26): 6033-44, 2006 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-21690816

RESUMO

X-ray diffraction of Ce(3+)-doped SrMgF(4) (SMF:Ce) crystals shows a superlattice structure, reflecting the distribution of Ce(3+) polyhedra centres observed in optical experiments. Optical absorption bands and fluorescence bands from the Ce(3+) polyhedra centres overlap in the vacuum ultraviolet (VUV) and ultraviolet (UV) regions, respectively, so that wide pumping and tuning ranges are expected for laser operation. The SMF:Ce crystals, as well as the isomorphous BaMgF(4), are candidates for a tunable laser gain material with nonlinear properties. The optical absorption, excitation, and fluorescence bands observed in the SMF:Ce crystals at low temperatures are ascribed to five distinct fluorescent centres. Three centres have well-known Ce(3+) optical characters, for example, fluorescence with double peaks separated by 2000 cm(-1) and five resolved absorption/excitation bands. These centres are assigned to Ce(3+)-polyhedra classified by weak and strong crystal fields as a consequence of the superlattice structure. The other two fluorescence bands observed in the visible region have 1.5-2 times larger linewidths than those of the former three bands. These bands are interpreted as optical transitions from complexes consisting of Ce(3+) and one or two electrons trapped at a vacancy of the nearest neighbour F(-) ligand ions.

4.
Biochem Soc Trans ; 32(Pt 6): 1107-9, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15506980

RESUMO

We have investigated the cellular distribution of p122RhoGAP, a GTPase-activating protein of Rho small GTPase and an activator of phospholipase C-delta(1). Immunofluorescence studies demonstrated that endogenous p122 is localized at the tips of actin stress fibres and co-localizes with vinculin in normal rat kidney cells. In immunoprecipitation studies, p122 co-precipitated with vinculin, indicating that p122 is localized at the sites of focal adhesion. We have also shown that the N-terminal half of p122 is responsible for this localization. It is conceivable, therefore, that p122 is involved in the reorganization of the actin cytoskeleton and focal adhesions that regulate cell-substratum adhesion and cell migration.


Assuntos
Proteínas Ativadoras de GTPase/metabolismo , Isoenzimas/metabolismo , Fosfolipases Tipo C/metabolismo , Animais , Sítios de Ligação , Adesão Celular , Rim/fisiologia , Modelos Biológicos , Fosfolipase C delta , Ligação Proteica , Ratos , Vinculina/fisiologia
5.
J Hand Surg Br ; 28(3): 218-23, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12809651

RESUMO

In order to investigate the mechanism of nerve irritation in thoracic outlet syndrome (TOS), we studied 150 patients who presented with symptoms of neurologic TOS between 1985 and 1999. They first performed various provocative physical manoeuvres and then underwent injection of contrast medium into the supraclavicular part of the brachial plexus. Several of the provocative manoeuvres were then repeated and radiographs were again obtained. Based on the neuroradiographs, we identified three subsets of patients; those with only compression (type 1 TOS, n=27, 18%), those with combined compression and stretching (type 2 TOS, n=111, 74%), and those with only stretching (type 3 TOS, n=12, 8%). We were able to correlate the neuroradiological subsets with symptoms elicited by pre-radiographic provocative manoeuvres; in 92 patients (61%) these were elicited by traction manoeuvres. We conclude that stretching is an important factor of nerve irritation in TOS.


Assuntos
Plexo Braquial/fisiopatologia , Síndromes de Compressão Nervosa/fisiopatologia , Exame Neurológico/métodos , Síndrome do Desfiladeiro Torácico/fisiopatologia , Adolescente , Adulto , Fatores Etários , Plexo Braquial/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Síndromes de Compressão Nervosa/diagnóstico por imagem , Postura/fisiologia , Radiografia , Rotação , Fatores Sexuais , Síndrome do Desfiladeiro Torácico/diagnóstico por imagem , Tração
6.
J Surg Res ; 101(2): 238-41, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11735281

RESUMO

BACKGROUND: Despite the established preservation method for major organs of perfusion followed by immersion at hypothermia, a standard preservation technique for skeletal muscle is still a matter of controversy. The purpose of this study is to examine the effect of perfusion on the preservation of skeletal muscle in amputated limbs. MATERIALS AND METHOD: The rat hindlimb was amputated for perfusion with Euro-Collins (EC) or University of Wisconsin (UW) solution at different perfusion pressures (40 or 100 cm-gravity). After certain ischemic periods (4 or 5 h), the skeletal muscle viability was determined by measuring the tissue content of adenosine triphosphate (ATP). RESULT: The UW solution perfusion group maintained better ATP levels than the EC solution group when the ischemic period was extended to 5 h. The perfusion pressure of 100 cm-gravity was more effective for preserving muscle viability than 40 cm-gravity with both EC and UW solutions. CONCLUSION: UW solution might be adequate to preserve muscle viability and perfusion pressure is recommended at 100 cm-gravity rather than at minimal pressure (40 cm-gravity), which washes out stagnant blood.


Assuntos
Isquemia/fisiopatologia , Músculo Esquelético/irrigação sanguínea , Soluções para Preservação de Órgãos , Preservação de Tecido , Adenosina/farmacologia , Trifosfato de Adenosina/análise , Alopurinol/farmacologia , Animais , Glutationa/farmacologia , Soluções Hipertônicas/farmacologia , Insulina/farmacologia , Masculino , Perfusão , Rafinose/farmacologia , Ratos , Ratos Endogâmicos Lew
7.
Neurology ; 57(10): 1767-73, 2001 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-11723261

RESUMO

OBJECTIVE: Televised images are the most common stimulus for provoking photosensitive seizures in photosensitive persons. To inhibit photosensitive seizures in photosensitive persons who do or do not have epilepsy, the authors sought nonpharmacologic methods for reducing the levels of photic stimulation of televised images. BACKGROUND: The authors found two types of pathophysiologic mechanisms (wavelength-dependent and quantity of light-dependent mechanisms) for photoparoxysmal responses (PPR). METHODS: The authors tested two different types of optical filters, one reflecting long-wavelength red light selectively, which stimulates a wavelength-dependent mechanism, and the other absorbing light in the visible spectrum evenly (neutral density filters). Inhibiting effects of optical filters were studied by conventional intermittent photic stimulation (IPS) using strobe light and novel photic stimulation using flashing cathode ray tubes (CRT). RESULTS: Both filters individually inhibited PPR insufficiently (less than 50%). Compound optical filters, composed of both types of filters, can inhibit the PPR, approximately 90% for IPS and 95% for photic stimulation with CRT. These compound optical filters do not destroy chromaticity of emissions from the television's CRT. CONCLUSIONS: These compound filters may be useful to prevent seizures induced by television in photosensitive persons.


Assuntos
Epilepsia Reflexa/prevenção & controle , Filtração/instrumentação , Estimulação Luminosa/efeitos adversos , Televisão/instrumentação , Adolescente , Criança , Pré-Escolar , Percepção de Cores/fisiologia , Apresentação de Dados/efeitos adversos , Epilepsia Reflexa/etiologia , Epilepsia Reflexa/fisiopatologia , Feminino , Humanos , Masculino , Óptica e Fotônica
8.
Acta Orthop Scand ; 72(4): 404-10, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11580130

RESUMO

Oxygen free radicals (OFR) and neutrophils are potent sources of reperfusion injury. We compared the effect of EPC-K1, a new OFR scavenger, and neutrophil depletion on the reperfusion injury in skeletal muscle, using an ischemic revascularized hindlimb model in rats. Warm ischemia, produced by vascular pedicle clamping, was sustained for 4 h. After 24 h of reperfusion, muscle function and damage were evaluated in 4 groups: a sham operation group, a control study group, a group treated by EPC-K1 (EPC group), and a group that received nitrogen mustard to induce neutropenia (NM group). Both the EPC and NM groups had limited muscle damage compared to the control group. The EPC group preserved muscle function significantly better than the control group and the mean isometric tetanic tension in the EPC group appeared to be higher than that in the NM group. Furthermore, levels of lipid peroxides in muscle and serum, and muscle edema in the EPC group, were significantly lower than in the NM group. Histological examinations supported these results. These findings suggest that limiting OFR generation by EPC-K1 in the early phase of reoxygenation is more potent than depletion of neutrophils in reducing reperfusion injury.


Assuntos
Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/uso terapêutico , Modelos Animais de Doenças , Sequestradores de Radicais Livres/uso terapêutico , Músculo Esquelético/lesões , Neutropenia/etiologia , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/imunologia , Vitamina E/análogos & derivados , Vitamina E/uso terapêutico , Animais , Ácido Ascórbico/química , Ácido Ascórbico/imunologia , Avaliação Pré-Clínica de Medicamentos , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/imunologia , Contração Isométrica/efeitos dos fármacos , Contagem de Leucócitos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Neutropenia/sangue , Neutrófilos/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Endogâmicos Lew , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/metabolismo , Vitamina E/química , Vitamina E/imunologia
9.
J Hand Surg Am ; 26(4): 663-9, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11466641

RESUMO

We studied the effect of repeated and continuous nerve strain using a rat forelimb model to investigate whether an innocuous level of strain applied continuously affects nerve function when applied repeatedly. We used the rat medial cord of the brachial plexus and assessed the effects of strain by studying nerve histology (blood-nerve barrier), function (grasping strength), and electrophysiology. Continuous stretching was applied to the rat forelimb for 1 hour at 2 N. After this strain neither histologic analysis, grasping strength, nor electrophysiologic analysis revealed any effect. We then applied repeated strain at both 60 and 120 times per hour; after the latter strain abnormalities in histology, grasping strength, and nerve conduction were identified. There results suggest that a small nerve strain applied repeatedly results in nerve dysfunction. Our data may help explain the cause of nonspecific neural symptoms in the upper extremities of patients with no objective findings.


Assuntos
Plexo Braquial/fisiologia , Transtornos Traumáticos Cumulativos/fisiopatologia , Animais , Neuropatias do Plexo Braquial/fisiopatologia , Eletrofisiologia , Membro Anterior , Força da Mão , Modelos Animais , Condução Nervosa , Ratos , Ratos Wistar , Estresse Mecânico
10.
J Surg Res ; 99(1): 1-6, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11421597

RESUMO

BACKGROUND: The ultimate aim of replantations and transplantations of skeletal muscle is to improve impaired function. The purpose of this study was to examine the contribution of varying durations of ischemia to postischemic blood flow in the skeletal muscle and the contribution of modulation of postischemic blood flow to skeletal muscle function and viability, using an ischemic revascularized hind limb model in rats. MATERIALS AND METHODS: Warm ischemia produced by vascular pedicle clamping was sustained for 90 min, 3 h, or 6 h. Postischemic blood flow was measured by a Doppler flowmeter or microsphere technique. In another series of experiments of 3-h ischemia, either saline or N(G)-methyl-l-arginine acetate (l-NMMA) was infused for the first 2 h of reperfusion. Postischemic blood flow was also measured. Muscle contractile function and viability were determined after 24 h of reperfusion. RESULTS: Postischemic blood flow was significantly increased during the first 10 min of reperfusion in the 90-minute ischemic group and during the first 2 h in the 3-h ischemic group compared with contralateral control blood flow. No significant increase in postischemic blood flow was noted in the 6-h ischemic group. Postischemic blood flow was significantly decreased by the l-NMMA infusion. Contractile function and viability of the tibialis anterior muscle and contractile function of the gastrocnemius muscle in the l-NMMA group were significantly increased. CONCLUSION: Reperfusion blood flow increased time dependently until 3 h of warm ischemia. Hyperemia deteriorated skeletal muscle contractile function, although it was well preserved by l-NMMA infusion to restrict the postischemic hyperemia.


Assuntos
Isquemia/fisiopatologia , Contração Isométrica , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/fisiopatologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Inibidores Enzimáticos/farmacologia , Membro Posterior , Hiperemia/fisiopatologia , Contração Isométrica/efeitos dos fármacos , Fluxometria por Laser-Doppler , Masculino , Microesferas , Músculo Esquelético/efeitos dos fármacos , Ratos , Ratos Endogâmicos Lew , Fluxo Sanguíneo Regional , Sobrevivência de Tecidos/efeitos dos fármacos , ômega-N-Metilarginina/farmacologia
11.
J Cell Sci ; 114(Pt 10): 1829-38, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11329369

RESUMO

Rac1, a member of the Rho family small GTPases, regulates E-cadherin-mediated cell-cell adhesion. However, it remains to be clarified how the localization and activation of Rac1 are regulated at sites of cell-cell contact. Here, using enhanced green fluorescence protein (EGFP)-tagged Rac1, we demonstrate that EGFP-Rac1 is colocalized with E-cadherin at sites of cell-cell contact and translocates to the cytosol during disruption of E-cadherin-mediated cell-cell adhesion by Ca(2+) chelation. Re-establishment of cell-cell adhesion by restoration of Ca(2)(+) caused EGFP-Rac1 to become relocalized, together with E-cadherin, at sites of cell-cell contact. Engagement of E-cadherin to the apical membrane by anti-E-cadherin antibody (ECCD-2) recruited EGFP-Rac1. We also investigated whether E-cadherin-mediated cell-cell adhesion induced Rac1 activation by measuring the amounts of GTP-bound Rac1 based on its specific binding to the Cdc42/Rac1 interactive binding region of p21-activated kinase. The formation of E-cadherin-mediated cell-cell adhesion induced Rac1 activation. This activation was inhibited by treatment of cells with a neutralizing antibody (DECMA-1) against E-cadherin, or with wortmannin, an inhibitor of phosphatidylinositol 3-kinase (PI 3-kinase). IQGAP1, an effector of Rac1, and EGFP-Rac1 behaved in a similar manner during the formation of E-cadherin-mediated cell-cell adhesion. Rac1 activation was also confirmed by measuring the amounts of coimmunoprecipitated Rac1 with IQGAP1 during the establishment of cell-cell adhesion. Taken together, these results suggest that Rac1 is recruited at sites of E-cadherin-mediated cell-cell adhesion and then activated, possibly through PI 3-kinase.


Assuntos
Caderinas/metabolismo , Células Epiteliais/metabolismo , Adesões Focais/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteínas Ativadoras de ras GTPase , Androstadienos/farmacologia , Animais , Anticorpos Monoclonais/farmacologia , Caderinas/imunologia , Proteínas de Transporte/análise , Proteínas de Transporte/metabolismo , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Células Epiteliais/citologia , Adesões Focais/química , Genes Reporter , Proteínas de Fluorescência Verde , Guanosina Trifosfato/metabolismo , Indicadores e Reagentes/metabolismo , Junções Intercelulares/química , Junções Intercelulares/metabolismo , Proteínas Luminescentes/genética , Fosfatidilinositol 3-Quinases/metabolismo , Testes de Precipitina , Transdução de Sinais/fisiologia , Wortmanina , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/análise , Proteínas rac1 de Ligação ao GTP/genética
12.
J Bone Joint Surg Br ; 83(2): 226-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11284570

RESUMO

We investigated the incidence of evidence of irritation of the brachial plexus in 119 patients with whiplash injuries sustained in road-traffic accidents. We compared the symptoms, physical signs, autonomic status, psychological status and findings from radiographs of the cervical spine using examination charts and a modified Cornell Medical Index Health questionnaire, in patients in two distinct groups: those with irritation of the brachial plexus and those without. There were 45 patients (37.8%) in the first group. The ratio of women to men was significantly higher in patients with irritation of the plexus as was the incidence of symptoms other than neck pain. There was no significant difference between the two groups with regard to psychological status or findings in radiographs of the cervical spine. Symptoms and signs attributable to stretching of the brachial plexus do occur in a significant proportion of patients after a whiplash injury. Their presence and persistence are associated with a poor outcome.


Assuntos
Plexo Braquial/fisiopatologia , Traumatismos em Chicotada/fisiopatologia , Adolescente , Adulto , Índice Médico de Cornell , Feminino , Humanos , Masculino , Cervicalgia/etiologia , Radiografia , Fatores Sexuais , Traumatismos em Chicotada/diagnóstico por imagem
13.
Mol Cell Biol ; 21(6): 2165-83, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11238950

RESUMO

We have previously proposed that IQGAP1, an effector of Rac1 and Cdc42, negatively regulates cadherin-mediated cell-cell adhesion by interacting with beta-catenin and by causing the dissociation of alpha-catenin from cadherin-beta-catenin-alpha-catenin complexes and that activated Rac1 and Cdc42 positively regulate cadherin-mediated cell-cell adhesion by inhibiting the interaction of IQGAP1 with beta-catenin. However, it remains to be clarified in which physiological processes the Rac1-Cdc42-IQGAP1 system is involved. We here examined whether the Rac1-IQGAP1 system is involved in the cell-cell dissociation of Madin-Darby canine kidney II cells during 12-O-tetradecanoylphorbol-13-acetate (TPA)- or hepatocyte growth factor (HGF)-induced cell scattering. By using enhanced green fluorescent protein (EGFP)-tagged alpha-catenin, we found that EGFP-alpha-catenin decreased prior to cell-cell dissociation during cell scattering. We also found that the Rac1-GTP level decreased after stimulation with TPA and that the Rac1-IQGAP1 complexes decreased, while the IQGAP1-beta-catenin complexes increased during action of TPA. Constitutively active Rac1 and IQGAP1 carboxyl terminus, a putative dominant-negative mutant of IQGAP1, inhibited the disappearance of alpha-catenin from sites of cell-cell contact induced by TPA. Taken together, these results indicate that alpha-catenin is delocalized from cell-cell contact sites prior to cell-cell dissociation induced by TPA or HGF and suggest that the Rac1-IQGAP1 system is involved in cell-cell dissociation through alpha-catenin relocalization.


Assuntos
Proteínas de Transporte/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteínas Ativadoras de ras GTPase , Animais , Sequência de Bases , Caderinas/metabolismo , Proteínas de Transporte/genética , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Células Cultivadas , Proteínas do Citoesqueleto/análise , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Cães , Proteínas de Fluorescência Verde , Fator de Crescimento de Hepatócito/farmacologia , Proteínas Luminescentes/análise , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Dados de Sequência Molecular , Mutação , Transporte Proteico , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , alfa Catenina , Proteína rhoA de Ligação ao GTP/metabolismo
14.
Biochem Biophys Res Commun ; 273(2): 712-7, 2000 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-10873669

RESUMO

Cadherin is a well-known cell-cell adhesion molecule, and it binds to beta-catenin, which in turn binds to alpha-catenin. However, little is known about the regulatory mechanism underlying the cadherin-mediated cell-cell adhesion. Here we purified two novel beta-catenin-interacting proteins with molecular masses of 180 kDa (p180) and 150 kDa (p150) from bovine brain cytosol by using glutathione S-transferase (GST)-beta-catenin affinity column chromatography. Mass spectral analysis revealed p180 to be identical to KIAA0313 which has a putative Rap1 guanine nucleotide exchange factor (GEF) domain and p150 to be the same as KIAA0705 which has a high degree of sequence similarity to the synaptic scaffolding molecule (S-SCAM), which binds beta-catenin and KIAA0313 in the yeast two-hybrid system and overlay assay, respectively (Ide et al., Biochem. Biophys. Res. Commun. 256, 456-461, 1999; Ohtsuka et al., Biochem. Biophys. Res. Commun. 265, 38-44, 1999). beta-Catenin was coimmunoprecipitated with KIAA0313 in Madin-Darby canine kidney II (MDCKII) cells, bovine brain cytosol, and EL cells. KIAA0313 and beta-catenin were partly colocalized at sites of cell-cell contact in MDCKII cells. Taken together, our data suggest that KIAA0313 associates with beta-catenin through KIAA0705 in vivo at sites of cell-cell contact.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Transativadores , Animais , Caderinas/metabolismo , Proteínas de Transporte/química , Bovinos , Adesão Celular , Cães , Técnicas In Vitro , Camundongos , Modelos Biológicos , Proteínas do Tecido Nervoso/química , Estrutura Terciária de Proteína , beta Catenina
15.
Can J Anaesth ; 47(3): 237-41, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10730734

RESUMO

PURPOSE: To compare the efficacy of ephedrine, dopamine and dobutamine for circulatory support during thoracic epidural anesthesia after anesthetic induction with propofol. METHODS: Forty patients undergoing lobectomy or mastectomy were divided into four groups of 10: a control group received no vasopressor; an ephedrine group received 5 mg ephedrine when the mean arterial pressure (MAP), measured every 2.5 min, decreased by 10% from baseline; dopamine and dobutamine groups received 5 microg x kg(-1) x min(-1) dopamine or 3 microg x kg(-1) x min(-1) dobutamine from five minutes after epidural injection of local anesthetic to the end of tracheal intubation. Anesthesia was induced with 2 mg x kg(-1) propofol. The MAP and heart rate (HR) were measured at baseline, 20 min after epidural injection, three minutes after propofol, and one minute after tracheal intubation. RESULTS: In the control group, MAP and HR decreased from 86+/-9 mmHg, 74+/-8 bpm to 62+/-9 mm Hg; P<0.0001, 60+/-8 bpm; P = 0.0003 after propofol. After tracheal intubation, MAP was restored to (81+/-13 mmHg, 70+/-13 bpm). In the ephedrine, dopamine, and dobutamine groups, MAP and HR remained unchanged during epidural anesthesia and propofol induction. However, after tracheal intubation, MAP and HR increased in the ephedrine (104+/-11 mm Hg; P = 0.004, 87+/-11 bpm; P<0.0001) and dobutamine (117+/-13 mm Hg; P = 0.0005, 100+/-11 bpm; P<0.0001) groups, but not in the dopamine group compared with baseline. CONCLUSION: Dopamine is preferable to ephedrine and dobutamine in providing hemodynamic stability during propofol induction and tracheal intubation following epidural anesthesia.


Assuntos
Adrenérgicos/uso terapêutico , Anestesia Epidural , Anestésicos Intravenosos/administração & dosagem , Cardiotônicos/uso terapêutico , Dobutamina/uso terapêutico , Dopamina/uso terapêutico , Efedrina/uso terapêutico , Hipotensão/tratamento farmacológico , Propofol/administração & dosagem , Simpatomiméticos/uso terapêutico , Análise de Variância , Anestésicos Locais/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Distribuição de Qui-Quadrado , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Intubação Intratraqueal , Masculino , Mastectomia , Pessoa de Meia-Idade , Pneumonectomia , Vasoconstritores/uso terapêutico
16.
J Biol Chem ; 274(40): 28537-41, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10497218

RESUMO

We have previously observed, using a green fluorescent protein (GFP) fusion system, that PLC-delta1 is localized mainly at the plasma membrane and in the cytosol, whereas little is present in the nucleus in Madin-Darby canine kidney cells (Fujii, M., Ohtsubo, M., Ogawa, T., Kamata, H., Hirata, H., and Yagisawa, H. (1999) Biochem. Biophys. Res. Commun. 254, 284-291). Herein, we demonstrate that PLC-delta1 has a functional nuclear export signal (NES) sequence in amino acid residues 164-177 of the EF-hand domain. The fluorescence of NES-disrupted GFP/PLC-delta1 expressed in Madin-Darby canine kidney cells was present not only at the plasma membrane and in the cytosol but also in the nucleus. Moreover, treatment with leptomycin B, a specific inhibitor of NES-dependent nuclear export, resulted in the accumulation of GFP/PLC-delta1 in the nucleus. A site-directed mutant containing a pleckstrin homology domain, which does not bind inositol 1,4,5-trisphosphate and cannot hydrolyze phosphatidylinositol 4,5-bisphosphate in vitro, accumulated in the nucleus to a much greater extent than wild-type GFP/PLC-delta1 after treatment with leptomycin B. These results suggest that PLC-delta1 is shuttled between the cytoplasm and the nucleus; its nuclear export is dependent on the leucine-rich NES sequence and its active nuclear import is regulated by an unidentified signal(s).


Assuntos
Núcleo Celular/metabolismo , Isoenzimas/metabolismo , Fosfolipases Tipo C/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Membrana Celular/metabolismo , Citosol/metabolismo , Primers do DNA , Cães , Isoenzimas/química , Isoenzimas/genética , Mutagênese Sítio-Dirigida , Fosfolipase C delta , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Homologia de Sequência de Aminoácidos , Fosfolipases Tipo C/química , Fosfolipases Tipo C/genética
17.
Acta Orthop Scand ; 70(2): 207-11, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10366926

RESUMO

EPC-K1, a phosphate diester of alpha-tocopherol and ascorbic acid, is a new hydroxyl radical scavenger. We examined the effects of EPC-K1 according to differences in the timing of its administration. Warm ischemia, produced by vascular pedicle clamping, was sustained for 4 hours. After 24 hours of reperfusion, muscle injury was evaluated in 4 groups: the first group received a sham operation, the second group was treated with an intravenous injection of EPC-K1 prior to ischemia, the third group was treated with EPC-K1 prior to reperfusion, and the fourth group was controls. Compared with the control group, both the preischemic and pre-reperfusion EPC-K1-treated groups showed a statistically significant amelioration in the reduction of isometric muscle contraction. There were also significant reductions in the muscle and serum levels of thiobarbituric acid reactive substances (TBA-RS) and muscle damage, indicated by the biochemical and histological study. A comparison of the timing of EPC-K1 administration revealed that only the muscle TBA-RS level in the pre-reperfusion EPC-K1-treated group was significantly higher than that in the preischemic EPC-K1-treated group. These observations indicate that EPC-K1 not only by preischemic but also by pre-reperfusion administration acted effectively on reperfusion injury in muscle, thereby improving muscle function.


Assuntos
Antioxidantes/administração & dosagem , Ácido Ascórbico/análogos & derivados , Sequestradores de Radicais Livres/uso terapêutico , Isquemia/prevenção & controle , Contração Isométrica/efeitos dos fármacos , Músculo Esquelético/irrigação sanguínea , Traumatismo por Reperfusão/prevenção & controle , Vitamina E/análogos & derivados , Animais , Ácido Ascórbico/administração & dosagem , Biópsia , Modelos Animais de Doenças , Esquema de Medicação , Avaliação Pré-Clínica de Medicamentos , Injeções Intravenosas , Isquemia/metabolismo , Isquemia/patologia , Isquemia/fisiopatologia , Masculino , Músculo Esquelético/fisiopatologia , Distribuição Aleatória , Ratos , Ratos Endogâmicos Lew , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fatores de Tempo , Vitamina E/administração & dosagem
18.
Appl Opt ; 38(35): 7202-5, 1999 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-18324267

RESUMO

We report on three-dimensional bright and long-lasting phosphorescence in a Ce(3+)-doped Ca(2)Al(2)SiO(7) crystal. After we scan with a focused 800-nm femtosecond pulsed laser, the path traversed by the focal point of the laser in the crystal emits bright and long-lasting phosphorescence that can be seen with the naked eye in the dark even 10 h after the removal of the activating laser. Absorption spectra of the crystal show that defect centers have formed after the laser irradiation, and the absorption that is due to the defect centers decays with time. It is suggested that a mechanism of the long-lasting phosphorescence consists of a thermostimulated recombination of holes and electrons at traps induced by the laser irradiation at room temperature.

19.
Int Endod J ; 31(4): 242-50, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9823113

RESUMO

The study aimed to evaluate intracanal irrigation procedures in eradicating bacteria from surface, shallow and deep layers of root dentine using extracted human teeth. Artificial bacterial smear layer was successfully produced by rubbing a mixture of dental plaque and artificially decalcified dentine or carious dentine on root canal walls. The reservoir holes were 3.5 mm in depth, 1 mm in diameter prepared 1.5 mm apart and parallel to the root canals on the decrowned planes, in which five separate bacterial species were placed (Actinomyces israelii, Fusobacterium nucleatum, Propionibacterium acnes, Streptococcus mutans and Streptococcus sanguis). Bacterial eradication after irrigation of the prepared canals was determined by bacterial recovery (i) from the root canal surfaces and shallow layers where bacteria were smeared artificially and (ii) from deeper layers of root canal dentine reservoir holes. Ultrasonic irrigation with 5.5% and 12% NaOCl eradicated bacteria from artificial smear layer (P < 0.0001), whilst 12% NaOCl irrigation with a syringe was insufficient. Ultrasonic irrigation with water or 15% EDTA-failed to eradicate bacteria from smeared surfaces. Ultrasonic irrigation with 12% NaOCl killed A. israelii, F. nucleatum, P. acnes, S. mutans, and S. sanguis placed in reservoir channels, although for F. nucleatum, a very small number of bacteria remained in five samples out of 12. Ultrasonic irrigation with less concentrated NaOCl failed to eliminate bacteria completely from reservoir channels in most samples. Ultrasonic irrigation with 12% NaOCl appeared to eliminate bacteria efficiently from surface, shallow and deep layers of root dentine.


Assuntos
Bactérias/efeitos dos fármacos , Cavidade Pulpar/microbiologia , Dentina/microbiologia , Irrigantes do Canal Radicular/farmacologia , Hipoclorito de Sódio/farmacologia , Actinomyces/efeitos dos fármacos , Contagem de Colônia Microbiana , Relação Dose-Resposta a Droga , Ácido Edético/farmacologia , Fusobacterium nucleatum/efeitos dos fármacos , Humanos , Microscopia Eletrônica de Varredura , Propionibacterium/efeitos dos fármacos , Camada de Esfregaço , Streptococcus/efeitos dos fármacos , Raiz Dentária/microbiologia , Ultrassom
20.
Acta Orthop Scand ; 68(4): 369-73, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9310042

RESUMO

L-ascorbic acid 2-[3,4-dihydro-2,5,7,8-tetramethyl- 2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6-yl hydrogen phosphate] potassium salt (EPC-K1), a phosphate diester of alpha-tocopherol and ascorbic acid, is a potent antioxidant. We examined the effects of EPC-K1 on ischemia-reperfusion injury in the skeletal muscle of rats, using an ischemic revascularized hind limb model. Warm ischemia (25 degrees C), produced by vascular pedicle clamping, was sustained for 4 hours. After 24 hours of reperfusion, skeletal muscle injury was evaluated in 2 groups: one group treated by intravenous injection of EPC-K1 (10 mg/kg) prior to ischemia, and a group of controls. The EPC-K1-treated group showed a statistically significant amelioration in the reduction of the isometric muscle contraction, inhibition of the elevation of the muscle wet- to dry-weight ratio, limitation of the muscle level of thiobarbituric acid reactive substances and the serum levels of creatine phosphokinase, lactate dehydrogenase and mitochondrial glutamic oxaloacetic transaminase, and reduction of the extent of muscle injury according to the histological findings. These observations indicate that EPC-K1 acted effectively on ischemia-reperfusion injury in the rat skeletal muscle and thereby improved muscle function.


Assuntos
Antioxidantes/uso terapêutico , Ácido Ascórbico/análogos & derivados , Sequestradores de Radicais Livres/uso terapêutico , Músculo Esquelético/irrigação sanguínea , Traumatismo por Reperfusão/tratamento farmacológico , Vitamina E/análogos & derivados , Animais , Antioxidantes/química , Ácido Ascórbico/química , Ácido Ascórbico/uso terapêutico , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Sequestradores de Radicais Livres/química , Contração Isométrica , Masculino , Ratos , Ratos Endogâmicos Lew , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Vitamina E/química , Vitamina E/uso terapêutico
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