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4.
Int J Sports Med ; 37(4): 305-12, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26667928

RESUMO

We tested a hypothesis that low-load squat training with slow movement and tonic force generation (LST) would increase muscle size and strength but not necessarily power. Healthy young men were assigned to LST [50% one-repetition maximum (1-RM) load, 3 s for lowering/lifting without pause: n=9] or low-load normal speed (LN: 50% 1-RM load, 1 s for lowering/lifting with 1-s pause; n=7) groups. Both groups underwent an 8-week squat training program (10 repetitions/set, 3 sets/day, and 3 days/week) using the assigned methods. Before and after the intervention, quadriceps femoris muscle thickness, maximal torque during isometric hip extension and knee extension, 1-RM squat, lifting power from squatting position and rate of electromyography rise (RER) in knee extensors during the task, leg extension power and vertical jump height were measured. After the intervention, the LN group showed no changes in all the variables. The LST group significantly (P<0.05) increased muscle thickness (6-10%), isometric hip extension torque (18%) and 1-RM squat (10%), but not isometric knee extension torque, lifting power and RER, leg extension power and vertical jump height. These results suggest that LST can increase muscle size and task-related strength, but has little effect on power production during dynamic explosive movements.


Assuntos
Força Muscular/fisiologia , Músculo Quadríceps/fisiologia , Levantamento de Peso/fisiologia , Eletromiografia , Articulação do Quadril/fisiologia , Humanos , Contração Isométrica , Articulação do Joelho/fisiologia , Perna (Membro) , Masculino , Movimento , Tamanho do Órgão , Postura , Torque , Adulto Jovem
6.
J Int Med Res ; 39(1): 51-63, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21672307

RESUMO

This study assessed the diagnostic value of QT dispersion for left ventricular hypertrophy (LVH) as determined by echocardiography. The QT and QRS interval parameters were determined automatically using computerized 12-lead electrocardiography in 153 Japanese out-patients. Corrected QT dispersion (QTcD) and maximal QRS duration (MaxQRS) were significantly correlated with left ventricular mass index. The sum of QTcD and MaxQRS showed the highest correlation with left ventricular mass index among QT and QRS interval parameters and their combinations. The cut-off points for LVH discrimination in this study were different to those reported in Western, mainly Caucasian, populations, suggesting the need for ethnicity-specific LVH detection criteria. A scoring system derived from multiple logistic regression analysis, employing a combination of QTcD, QRS time-voltage product and ST-T change, showed a specificity of 86.3%. It was concluded that QTcD, in addition to QRS time-voltage product and ST-T change, improved the detection of LVH.


Assuntos
Povo Asiático/etnologia , Ecocardiografia/métodos , Eletrocardiografia/métodos , Hipertrofia Ventricular Esquerda/diagnóstico , Idoso , Feminino , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/etnologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Pacientes Ambulatoriais , Estudos Prospectivos , Sensibilidade e Especificidade , População Branca/etnologia
7.
Neuroscience ; 166(3): 819-31, 2010 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-20074624

RESUMO

Recent studies have demonstrated the contribution of the gamma subunit of the Fc receptor of IgG (FcRgamma) to neuronal death following ischemic injury and Parkinson's disease. We examined the role of FcRgamma in hippocampal pyramidal cell death induced by kainic acid (KA). FcRgamma-deficient mice (FcRgamma-/-) and their FcRgamma+/+ littermates (wild type, B6) received an injection of KA into the dorsal hippocampus. Pyramidal cell death was quantified 24 and 72 h after the injection. The number of survived pyramidal cells was significantly larger in FcRgamma-/- mice than in B6 mice in both the CA1 and CA3. Immunohistochemical and immunofluorescent studies detected FcgammaRIIB protein in parvalbumin neurons, whereas FcgammaRIII and FcgammaRI proteins were detected in microglial cells. No activated microglial cells were detected 24 h after the KA injection in FcRgamma-/- mice, whereas many activated microglial cells were present in B6 mice. The production of nitrotyrosine as well as of the inducible nitric oxide synthase and cyclooxygenase-2 proteins, increased by 16 h after the KA injection in B6 mice. In addition, tissue plasminogen activator and metalloproteinase-2 proteins increased. By contrast, the magnitude of oxidative stress and the increase in protease expression were mild in FcRgamma-/- mice. Co-injection of a neutralizing antibody against FcgammaRll and FcgammaRlll with KA abolished pyramidal cell death and microglial activation. In addition, the neutralizing antibody reduced oxidative stress and expression of proteases. These observations suggested a role for FcgammaRllB in parvalbumin neurons as well as FcRgamma in microglia in pyramidal cell death.


Assuntos
Hipocampo/efeitos dos fármacos , Ácido Caínico/farmacologia , Células Piramidais/efeitos dos fármacos , Receptores de IgG/fisiologia , Animais , Anticorpos Neutralizantes/farmacologia , Morte Celular , Ciclo-Oxigenase 2/biossíntese , Hipocampo/citologia , Hipocampo/metabolismo , Metaloproteinase 2 da Matriz/biossíntese , Camundongos , Camundongos Knockout , Microglia/metabolismo , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo II/biossíntese , Estresse Oxidativo , Células Piramidais/citologia , Células Piramidais/metabolismo , Receptores de IgG/antagonistas & inibidores , Receptores de IgG/genética , Receptores de IgG/metabolismo , Ativador de Plasminogênio Tecidual/biossíntese , Tirosina/análogos & derivados , Tirosina/biossíntese
8.
Kyobu Geka ; 62(10): 880-3, 2009 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-19764493

RESUMO

The patient was a 41-year-old female and had been pointed out an abnormal shadow at the left lung apex on the chest X-ray film. Chest computed tomography (CT) scan and magnetic resonance imaging (MRI) revealed a left upper mediastinal mass at the Th1 to Th2 level, measuring 30 mm in size, which was suspected to be a neurogenic tumor. Surgical removal of the tumor using thoracoscopic procedure through 3 chest ports combined with a supraclavicular approach was successfully performed. She was discharged from the hospital on the 7th postoperative day. A pathological examination revealed the tumor to be benign neurilemmoma.


Assuntos
Neoplasias do Mediastino/cirurgia , Neurilemoma/cirurgia , Adulto , Feminino , Humanos , Toracoscopia
9.
J Colloid Interface Sci ; 320(1): 353-9, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18221752

RESUMO

The force of double-layer interaction between dissimilar flat oxide surfaces charged oppositely at infinite separation and with Stern-Grahame layers was calculated as a function of the surface separation under the conditions of charge regulation. The interaction force showed a monotonic attraction with respect to the surface separation, lying between constant surface potential and constant surface charge conditions. The variations of surface potentials and surface charge densities of respective double layers were also presented as functions of the surface separation. When the negative diffuse-layer potential at infinite separation changed its sign to positive as a result of specific adsorption of cations on the negatively changed surface, the double-layer interaction force showed a repulsive force barrier followed by an attraction at some particular separation.

10.
Biosystems ; 88(3): 334-42, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17182171

RESUMO

Brain-related researches encompass many fields of studies and usually involve worldwide collaborations. Recognizing the value of these international collaborations for efficient use of resources and improving the quality of brain research, the International Neuroinformatics Coordinating Facility (INCF) started to coordinate the effort of establishing neuroinformatics (NI) centers and portal sites among the different participating countries. These NI centers and portal sites will serve as the conduit for the interchange of information and brain-related resources among different countries. In Japan, several NI platforms under the support of NIJC (NI Japan Center) are being developed with one platform called, Visiome, already operating and publicly accessible at "http://www.platform.visiome.org". Each of these platforms requires their own set of keywords that represent important terms covering their respective fields of study. One important function of this predefined keyword list is to help contributors classify the contents of their contributions and group related resources. It is vital, therefore, that this predefined list should be properly chosen to cover the necessary areas. Currently, the process of identifying these appropriate keywords relies on the availability of human experts which does not scale well considering that different areas are rapidly evolving. This problem prompted us to develop a tool to automatically filter the most likely terms preferred by human experts. We tested the effectiveness of the proposed approach using the abstracts of the Vision Research Journal (VR) and Investigative Ophthalmology and Visual Science Journal (IOVS) as source files.


Assuntos
Biologia Computacional , Bases de Dados Factuais , Neurobiologia , Animais , Biologia Computacional/estatística & dados numéricos , Apresentação de Dados , Humanos , Neurobiologia/estatística & dados numéricos , Biologia de Sistemas/estatística & dados numéricos
11.
J Colloid Interface Sci ; 296(1): 150-8, 2006 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-16209871

RESUMO

Models of surfaces with intrinsic ionisable amphoteric surface sites governed by the dissociation of acid-base potential determining ion species together with the capacity for the adsorption of anion and cations of the supporting electrolyte are required to describe both the results of electrokinetic and titration measurements of inorganic oxides. The Gouy-Chapman-Stern-Grahame (CGSG) model is one such model that has been widely used in the literature. The electrical double layer interaction between two dissimilar CGSG surfaces has been studied by Usui recently [S. Usui, J. Colloid Interface Sci. 280 (2004) 113] where erroneous discontinuities in the slope of the pressure-separation relation were observed. We revisit this calculation and provide a simple general methodology to analyse the electrical double layer interaction between dissimilar ionisable surfaces with ion adsorption.

12.
Biosystems ; 82(2): 168-88, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16115726

RESUMO

In a typical optimization problem, the main goal is to search for the appropriate values of the variables that provide the optimal solution of the given function. In artificial neural networks (ANN), this translates to the minimization of the error surface during training such that misclassification is minimized during generalization. However, since optimal training performance does not necessarily imply optimal generalization due to the possibility of overfitting or underfitting, we developed SEPA (Structure Evolution and Parameter Adaptation) which addressed these issues by simultaneously evolving ANN structure and weights. Since SEPA primarily relies on the perturbation function to bring variation in its population, this follow-up study aims to find out SEPAs evolvability, optimality, and robustness in other perturbation functions. Our findings indicate that SEPAs optimal generalization performances are stable and robust from the effect of the different perturbation functions. This is due to the feedback loop between its architecture evolution and weight adaptation such that any shortcoming of the former is compensated by the latter, and vice versa. Our results strongly suggest that proper ANN design requires simultaneous adaptation of ANN structure and weights to avoid one-sided or bias convergence to either the weight or architecture space.


Assuntos
Algoritmos , Modelos Teóricos , Redes Neurais de Computação , Biologia de Sistemas/métodos , Classificação/métodos , Simulação por Computador , Retroalimentação , Processos Estocásticos
13.
J Colloid Interface Sci ; 280(1): 113-9, 2004 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-15476781

RESUMO

The force of interaction between two flat double layers with dissimilar surface potentials but of the same signs, in contact with 1-1 electrolyte solutions (0.001, 0.01, and 0.1 M), was calculated as a function of the surface separation. The calculation was carried out on the basis of the Gouy-Chapman-Stern-Grahame double-layer model, incorporating the site-dissociation and site-binding model used previously for many oxide studies. The results demonstrated that the interaction force under surface charge regulation was always repulsive, increasing progressively with decreasing surface separation. This result is in contrast to the predictions of previous theories that are based on the Gouy-Chapman (GC) double-layer model. Dependence of surface potentials and surface charge densities on the surface separation is also presented.

14.
Diabetes Res Clin Pract ; 59(3): 181-9, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12590014

RESUMO

The effects of bezafibrate and pravastatin on remnant-like lipoprotein particles (RLPs) and lipoprotein subclasses were compared in type 2 diabetes. Bezafibrate (400 mg/day) and pravastatin (10 mg/day) were given to 27 Japanese diabetics in a randomized crossover design. RLP cholesterol (RLP-C) and RLP triglyceride (RLP-TG) were measured by an immunoseparation technique. LDL and HDL were separated each into three subclasses (large, medium, small) and their cholesterol (C) contents were measured by an HPLC method. RLP-C was reduced more effectively by pravastatin (bezafibrate -16.0% vs. pravastatin -40.6%, P < 0.05), whereas RLP-TG was reduced more effectively by bezafibrate (-55.2% vs. -35.0%, P < 0.05). Further, pravastatin decreased large and small LDL-C levels equally (large; -23.6%; medium; -17.2%, small; -21.0%), while bezafibrate produced a relatively larger reduction in small LDL-C (-12.1; -16.9; -21.5%). Whereas bezafibrate significantly decreased large HDL-C and increased medium and small HDL-C (-49.6; 34.1; 35.8%), pravastatin significantly increased only medium HDL-C (5.2; 9.4; 5.9%). Bezafibrate reduced RLP-C and RLP-TG more effectively in patients with high TG levels, whereas pravastatin's effect was not markedly influenced by the initial TG level. Thus measurements of RLP-C, RLP-TG, and HPLC subclasses revealed that bezafibrate and pravastatin differently influence the lipoprotein status in type 2 diabetes.


Assuntos
Bezafibrato/administração & dosagem , Diabetes Mellitus Tipo 2/complicações , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Hipertrigliceridemia/tratamento farmacológico , Hipolipemiantes/administração & dosagem , Pravastatina/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Colesterol/sangue , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Humanos , Hipertrigliceridemia/sangue , Hipertrigliceridemia/complicações , Lipoproteínas/sangue , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue
15.
Apoptosis ; 7(6): 519-25, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12370494

RESUMO

Intracellular acidification is known to be involved in the initiation phase of apoptosis. However, the necessity of intracellular acidic conditions in the execution phase of apoptosis remains unknown. In this study, we found that in HL-60 cells imidazole induces cell death, associated with intracellular acidification, caspase-3 activation and DFF-45 cleavage, but not oligonucleosomal DNA fragmentation. A caspase inhibitor prevented cell death but not intracellular acidification. When pHi was neutralized by changing from imidazole-containing medium to fresh medium, oligonucleosomal DNA fragmentation and increased caspase-3 activity was observed in the imidazole-treated HL-60 cells. Furthermore, the DNA fragmentation induced by intracellular neutralization was inhibited by caspase inhibitor treatment. These results indicate that imidazole induces caspase-dependent cell death, and suggest that maintaining pHi in the neutral range is essential for the induction of oligonucleosomal DNA fragmentation in the execution phase of apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Imidazóis/farmacologia , Proteínas Reguladoras de Apoptose , Caspase 3 , Caspases/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Células HL-60 , Humanos , Concentração de Íons de Hidrogênio , Líquido Intracelular/metabolismo , Proteínas/metabolismo
16.
J Colloid Interface Sci ; 250(2): 371-8, 2002 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-16290674

RESUMO

The zeta (zeta) potential of an insoluble monolayer of stearic acid at the air-water interface was measured as a function of pH in the presence of 0.0001, 0.001, and 0.01 M NH4NO3. The zeta potential was measured by means of the plane interface technique which involved the determination of the electrophoretic velocity profile of reference (polystyrene latex) particles along the solution depth in a rectangular open quartz cell. The zeta vs pH relationship at 0.001 and 0.01 M NH4NO3 was analyzed in terms of the Gouy-Chapman-Stern-Grahame model for electrical double-layer incorporating a simple site-binding model used previously for many oxide and latex colloid studies. The dissociation constant (pKa) of stearic acid monolayer and double-layer parameters such as integral capacitances of inner and outer Helmholtz layers and the complexation constant of counterion complexes were also estimated.

17.
Shokuhin Eiseigaku Zasshi ; 42(3): 206-9, 2001 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-11577395

RESUMO

An unknown peak (peak A) was detected in a mass chromatogram of komatsuna extract containing a high concentration of phenthoate (PAP), and it was considered to be O,O,S-trimethyl phosphorodithioate (OOS). Although it is generally known that OOS exists as an impurity in technical malathion and PAP, it has not been reported that OOS is present in crops. Since an OOS standard is not commercially available, OOS was separated and purified from commercial emulsifiable malathion. Peak A was confirmed to be OOS by GC/MS using the purified OOS. The concentration of OOS was estimated to be 0.02 microgram/g. It is supposed that OOS was detected in crops because they contained a high concentration of PAP residue.


Assuntos
Organotiofosfatos/análise , Compostos Organotiofosforados/química , Verduras/química , Cromatografia Gasosa , Espectrometria de Massas , Resíduos de Praguicidas/análise
18.
J Neurophysiol ; 86(4): 2118-22, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11600668

RESUMO

The consequence of exposure to microgravity on the otolith organs was studied by recording the responses of vestibular nerve afferents supplying the utricular otolith organ to inertial accelerations in four toadfish, Opsanus tau, sequentially for 5 days following two National Aeronautics and Space Administration shuttle orbital flights. Within the first day postflight, the magnitude of response to an applied translation was on average three times greater than for controls. The reduced gravitational acceleration in orbit apparently resulted in an upregulation of the sensitivity of utricular afferents. By 30 h postflight, responses were statistically similar to control. The time course of return to normal afferent sensitivity parallels the reported decrease in vestibular disorientation in astronauts following return from space.


Assuntos
Adaptação Fisiológica/fisiologia , Sensação Gravitacional/fisiologia , Neurônios/fisiologia , Voo Espacial , Nervo Vestibular/fisiologia , Batracoidiformes , Eletrofisiologia , Humanos , Membrana dos Otólitos/inervação , Membrana dos Otólitos/fisiologia , Nervo Vestibular/citologia
19.
J Biochem ; 130(2): 199-205, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11481036

RESUMO

The protein B23 is a major nucleolar phosphoprotein comprising two isoforms, B23.1 and B23.2, which differ only in their carboxyl-terminal short sequences, the N-terminal 255 residues being identical in both forms. Both B23.1 and B23.2 stimulated immunoaffinity-purified calf thymus DNA polymerase alpha in a dose-dependent manner. The stimulatory effect of protein B23.1, the longer isoform, was found to be 2-fold greater than that of B23.2. Purified DNA polymerase alpha bound tightly to a protein B23.1-immobilized column, while it bound weakly to a protein B23.2-immobilized column. Surface plasmon resonance studies by BIAcore further showed that protein B23.1 bound to the DNA polymerase alpha-(dA).(dT) complex more tightly than did protein B23.2. The protein B23 isoforms appear to interact directly with the DNA polymerase alpha protein and not through the bound nucleic acid. These observations indicated that protein B23 physically bound to the DNA polymerase alpha and stimulated the enzyme activity. Product analyses showed that protein B23 greatly enhanced the reaction both in amount and length of product DNA, whereas it did not significantly alter the processivity of polymerization. In contrast, protein B23 effectively protected DNA polymerase alpha from heat inactivation. These results suggest that protein B23 stabilizes DNA polymerase alpha that is detached from product DNA, allowing the enzyme to be recruited for further elongation. Moreover, experiments using various C-terminal deletion mutants of protein B23 indicated that 12 amino acids at the C-terminal end of B23.1, which are absent in B23.2, may be essential for the full stimulation of the DNA polymerase alpha.


Assuntos
DNA Polimerase I/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Sequência de Aminoácidos , Animais , Estabilidade Enzimática , Dados de Sequência Molecular , Mutação , Proteínas Nucleares/genética , Nucleofosmina , Ligação Proteica , Isoformas de Proteínas , Estrutura Terciária de Proteína , Ratos , Proteínas Recombinantes/metabolismo , Ressonância de Plasmônio de Superfície
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