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1.
Proc IEEE Int Symp Biomed Imaging ; 2019: 303-306, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32461782

RESUMO

Paraseptal emphysema (PSE) is a relatively unexplored emphysema subtype that is usually asymptomatic, but recently associated with interstitial lung abnormalities which are related with clinical outcomes, including mortality. Previous local-based methods for emphysema subtype quantification do not properly characterize PSE. This is in part for their inability to properly capture the global aspect of the disease, as some the PSE lesions can involved large regions along the chest wall. It is our assumption, that path-based approaches are not well-suited to identify this subtype and segmentation is a better paradigm. In this work we propose and introduce the Slice-Recovery network (SR-Net) that leverages 3D contextual information for 2D segmentation of PSE lesions in CT images. For that purpose, a novel convolutional network architecture is presented, which follows an encoding-decoding path that processes a 3D volume to generate a 2D segmentation map. The dataset used for training and testing the method comprised 664 images, coming from 111 CT scans. The results demonstrate the benefit of the proposed approach which incorporate 3D context information to the network and the ability of the proposed method to identify and segment PSE lesions with different sizes even in the presence of other emphysema subtypes in an advanced stage.

2.
Phys Rev Lett ; 120(22): 221301, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29906152

RESUMO

A search for boosted dark matter using 161.9 kt yr of Super-Kamiokande IV data is presented. We search for an excess of elastically scattered electrons above the atmospheric neutrino background, with a visible energy between 100 MeV and 1 TeV, pointing back to the Galactic center or the Sun. No such excess is observed. Limits on boosted dark matter event rates in multiple angular cones around the Galactic center and Sun are calculated. Limits are also calculated for a baseline model of boosted dark matter produced from cold dark matter annihilation or decay. This is the first experimental search for boosted dark matter from the Galactic center or the Sun interacting in a terrestrial detector.

3.
Rev Sci Instrum ; 87(2): 02C106, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26932116

RESUMO

Dust particles of µm size produced by a monoplasmatron ion source are observed by a laser light scattering. The scattered light signal from an incident laser at 532 nm wavelength indicates when and where a particle passes through the ion beam transport region. As the result, dusts with the size more than 10 µm are found to be distributed in the center of the ion beam, while dusts with the size less than 10 µm size are distributed along the edge of the ion beam. Floating potential and electron temperature at beam transport region are measured by an electrostatic probe. This observation can be explained by a charge up model of the dust in the plasma boundary region.

4.
Rev Sci Instrum ; 85(2): 02A714, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593448

RESUMO

Argon ion beam fluctuation from an AC filament driven Bernas-type ion source is observed. The ion beam was measured by an 8 measurement elements beam profile monitor. The amplitude of the beam current fluctuation stayed in the same level from 100 Hz to 1 kHz of the filament heating frequency. The beam current fluctuation frequency measured by the beam profile monitor was equal to the frequency of the AC filament operation. The fluctuation amplitudes of the beam current by AC operation were less than 7% and were in the same level of the DC operation.

5.
J Cancer Res Clin Oncol ; 139(10): 1701-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23974271

RESUMO

PURPOSE: The incidence of hot flashes under hormone manipulation therapy is so high that this symptom caused by sex hormone blocking agents has been bothering patients and has a negative impact on their quality of life. Venlafaxine and gabapentin are most promising novel nonestrogenic agents to control the symptom. We seek to quatitatively summarize the efficacy of these novel agents. PATIENTS AND METHODS: We conducted a meta-analysis of randomized controlled studies on the efficacy of venlafaxine/gabapentin to hot flashes in cancer patient under hormone deprivation therapies. A search for Medline, Embase, Cochrane Central Register of Controlled Trials, Ichushi, and Google Scholar yielded 733 citations, which were independently assessed by two authors. We estimated overall effect sizes and its 95 % confidence intervals (CI) for the efficacy of these agents compared with the controls with standardized mean difference. RESULTS: A total of 5 studies involving 588 cancer patients with hot flashes finally fulfilled the predefined inclusion criteria. Overall effect size of the efficacy of venlafaxine/gabapentin was -0.630 (95 % CI [-0.801, -0.459]). CONCLUSION: Venlafaxine/gabapentin significantly improved hot flashes in cancer patients under hormone manipulation therapies.


Assuntos
Aminas/uso terapêutico , Antineoplásicos Hormonais/efeitos adversos , Ácidos Cicloexanocarboxílicos/uso terapêutico , Cicloexanóis/uso terapêutico , Fogachos/tratamento farmacológico , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Ácido gama-Aminobutírico/uso terapêutico , Gabapentina , Fogachos/induzido quimicamente , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Cloridrato de Venlafaxina
6.
J Synchrotron Radiat ; 20(Pt 2): 219-25, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23412477

RESUMO

A Si(111) winged crystal has been designed to minimize anticlastic bending and improve sagittal focusing efficiency. The crystal was thin with wide stiffening wings. The length-to-width ratio of the crystal was optimized by finite element analysis, and the optimal value was larger than the `golden value'. The analysis showed that the slope error owing to anticlastic bending is less than the Darwin width. The X-rays were focused two-dimensionally using the crystal and a tangentially bent mirror. The observed profiles of the focal spot agreed well with the results of a ray-tracing calculation in the energy range from 8 to 17.5 keV. X-ray diffraction measurements with a high signal-to-noise ratio using this focusing system were demonstrated for a small protein crystal.


Assuntos
Muramidase/química , Difração de Raios X/métodos , Animais , Cristalização/instrumentação , Desenho de Equipamento , Síncrotrons
8.
J Electromyogr Kinesiol ; 12(1): 37-43, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11804810

RESUMO

A new method for estimating the distribution of conduction velocities (DCV) of peripheral nerve fibers has been developed. It also enables estimation of single nerve fiber action potential (SFAP), which agrees with the physiological knowledge. Two compound nerve action potentials (CAPs) elicited by electrical stimulation of a nerve bundle were recorded at different conduction distances. The distances between the stimulation and recording electrodes were measured on the skin surface along the nerve bundle. Starting with an arbitrary SFAP, the first estimated DCV was calculated from a CAP by the regularized non-negative least squares method. The next SFAP was then calculated by deconvolution of the other CAP and the estimated DCV. A lowpass filter with an appropriate cutoff frequency was used to obtain better conversion. The process was iterated until the CAP error defined as /CAP(calculated)-CAP/(2) was small enough. The conduction distances contained errors in measurement, especially in the distal segment, that distorted the estimated results. The Fibonacci search, therefore, was adopted to optimize the distance according to the CAP error. The accuracy of this method was demonstrated by a simulation study performed with two CAPs calculated from an arbitrary bimodal DCV and a biphasic SFAP to which a Gaussian white noise was added. The reliability of this method was checked in normal subjects by recording a pair of CAPs elicited by stimulation of the median nerve at the wrist and the elbow.


Assuntos
Potenciais de Ação/fisiologia , Condução Nervosa/fisiologia , Nervos Periféricos/fisiologia , Adulto , Estimulação Elétrica , Eletrodos , Eletrofisiologia , Humanos , Análise dos Mínimos Quadrados , Masculino , Modelos Neurológicos
9.
J Immunol ; 167(6): 3156-63, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11544301

RESUMO

A novel IFN-like molecule, limitin, was recently identified and revealed to suppress B lymphopoiesis through the IFN-alphabeta receptor, although it lacked growth suppression on myeloid and erythroid progenitors. Here we have studied diverse effects of limitin on T lymphocytes and compared limitin with previously known IFNs. Like IFN-alpha and -beta, limitin modified immunity in the following responses. It suppressed mitogen- and Ag-induced T cell proliferation through inhibiting the responsiveness to exogenous IL-2 rather than suppressing the production of IL-2. In contrast, limitin enhanced cytotoxic T lymphocyte activity associated with the perforin-granzyme pathway. To evaluate the effect of limitin in vivo, a lethal graft-versus-host disease assay was established. Limitin-treatment of host mice resulted in the enhancement of graft-versus-host disease. Limitin did not influence thymocyte development either in fetal thymus organ cultures or in newborn mice injected with limitin-Ig, suggesting that limitin is distinguishable from IFN-alpha and -beta. From these findings, it can be speculated that the human homolog of limitin may be applicable for clinical usage because of its IFN-like activities with low adverse effects on, for example, T lymphopoiesis, erythropoiesis, and myelopoiesis.


Assuntos
Citocinas/fisiologia , Ativação Linfocitária/efeitos dos fármacos , Subpopulações de Linfócitos T/efeitos dos fármacos , Adjuvantes Imunológicos/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Citocinas/efeitos dos fármacos , Citocinas/toxicidade , Citotoxicidade Imunológica , Avaliação Pré-Clínica de Medicamentos , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/imunologia , Hematopoese/efeitos dos fármacos , Imunossupressores/farmacologia , Interferon-alfa/farmacologia , Interferon beta/farmacologia , Interleucina-2/análise , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Muromonab-CD3/farmacologia , Técnicas de Cultura de Órgãos , Ovalbumina/imunologia , Quimera por Radiação , Subpopulações de Linfócitos T/imunologia , Timo/citologia , Timo/embriologia
10.
Pharmacopsychiatry ; 34(2): 73-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11302567

RESUMO

In order to examine the effects of risperidone on cognitive impairment in schizophrenia, event-related potentials (ERPs) were recorded before and after switching from conventional neuroleptics to risperidone in schizophrenic patients. ERPs were recorded during two auditory discrimination tasks (an oddball task and a distraction task) in 10 medicated schizophrenic patients during conventional neuroleptic and risperidone treatments. The amplitudes and latencies of N 100 and P300 component were measured in ERPs for target stimuli in the oddball task and in ERPs for target and novel stimuli in the distraction task. Although N 100 amplitude and latency and P 300 amplitude did not change significantly after switching the drug compared to that during conventional neuroleptic treatment, P 300 latency for target stimuli shortened significantly during risperidone treatment in both tasks, accompanied by the shortening of the reaction time in the distraction task. The P 300 latency change did not correlate with the change of the severity of psychopathology. These findings suggest that risperidone may speed the information processing in schizophrenic patients, contributing to the improvement of cognitive functions.


Assuntos
Antipsicóticos/farmacologia , Potenciais Evocados P300/efeitos dos fármacos , Risperidona/farmacologia , Esquizofrenia/fisiopatologia , Adulto , Antipsicóticos/uso terapêutico , Atenção/efeitos dos fármacos , Feminino , Humanos , Masculino , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Risperidona/uso terapêutico , Esquizofrenia/tratamento farmacológico
11.
Nature ; 414(6866): 893-5, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11780058

RESUMO

Deformation of solid materials affects not only their microstructures, but also their microchemistries. Although chemical unmixing of initially homogeneous multicomponent solids is known to occur during deformation by diffusion creep, there has been no report on their chemical zoning due to deformation by dislocation creep, in either natural samples or laboratory experiments. Here we report striped iron zoning of olivine ((Mg,Fe)2SiO4) in deformed peridotites, where the iron concentration increases at subgrain boundaries composed of edge dislocations. We infer that this zoning is probably formed by alignment of edge dislocations dragging a so-called Cottrell 'atmosphere' of solute atoms (iron in this case) into subgrain boundaries during deformation of the olivine by dislocation creep. We have found that the iron zoning does not develop in laboratory experiments of high strain rates where dislocations move too fast to drag the Cottrell atmosphere. This phenomenon might have important implications for the generation of deep-focus earthquakes, as transformation of olivine to high-pressure phases preferentially occurs in high-iron regions, and therefore along subgrain boundaries which would be preferentially aligned in plastically deformed mantle peridotites.

12.
J Rehabil Med ; 33(6): 249-55, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11766953

RESUMO

In this study, we investigated the relationship between the motor evoked potentials obtained from trunk muscles and the clinical function of trunk muscle. Twenty patients with unilateral hemispheric stroke and 11 healthy adults were examined. The responses of the bilateral external oblique muscles and the erector spinae muscles to the magnetic stimulation of multiple sites over both cortical hemispheres were recorded. Trunk muscle performance was assessed using the Trunk Control Test and Stroke Impairment Assessment Set. In the stroke group, stimulation of the affected hemisphere resulted in a motor evoked potential in only one patient, while the other 19 stroke patients produced no response to stimulation of the affected hemisphere. Stimulation of the unaffected hemisphere evoked bilateral responses in 19 patients. Further, stimulation of the unaffected hemisphere in the stroke group produced larger motor evoked potentials in the ipsilateral muscles than the motor evoked potentials recorded in the ipsilateral muscles of the control group. The clinical assessment scores of trunk function (i.e. Trunk Control Test and trunk items of Stroke Impairment Assessment Set) were correlated with the amplitudes of the motor evoked potentials of the ipsilateral external oblique muscle that were evoked by stimulation of the unaffected hemisphere. Our results suggest that the recovery of trunk function after stroke is associated with an increase in ipsilateral motor evoked potentials in the external oblique muscle upon stimulation of the unaffected hemisphere, suggesting a role for compensatory activation of uncrossed pathways in recovery of trunk function.


Assuntos
Potencial Evocado Motor , Músculo Esquelético/fisiopatologia , Paresia/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Estimulação Magnética Transcraniana , Adulto , Idoso , Mapeamento Encefálico , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiopatologia , Paresia/etiologia , Acidente Vascular Cerebral/complicações
13.
Cancer Res ; 60(15): 4262-9, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10945640

RESUMO

A new human myeloma cell line, OPM-6, was established from the peripheral blood of a patient with advanced IgG-kappa plasma cell leukemia. Cytogenetic and phenotypic analysis confirmed that the cells were derived from the patient's leukemic cells. Insulin-like growth factor-1 (IGF-1) acts as an autocrine growth factor in these cells. In addition, OPM-6 cells were particularly sensitive to dexamethasone (DEX), when endogenous IGF-1 was blocked. Under these conditions, >95% of the DEX-treated cells died within 36 h. Therefore, OPM-6 represents a potentially powerful tool for the analysis of the molecular mechanisms of DEX-induced apoptosis, because it is possible to easily analyze the direct effects of DEX using this system. Using this culture system of OPM-6, we demonstrated that the treatment with DEX plus a monoclonal antibody to the human IGF-1 receptor (alphaIGF-1R) leads to the down-regulation of the gene expression of Bcl-xL, an antiapoptotic gene, and the activation of CPP32 during this apoptotic process. IFN-alpha as well as IL-6 prevented DEX plus alphaIGF-1R-induced apoptosis, and this prevention was blocked by the mitogen-activated protein kinase kinase inhibitor, PD098059, or the phosphatidylinositol 3-kinase inhibitor, wortmannin. Therefore, both IL-6 and IFN-alpha blocked DEX plus alphaIGF-1R-induced apoptosis through activation of the mitogen-activated protein kinase and phosphatidylinositol 3-kinase pathways.


Assuntos
Apoptose/efeitos dos fármacos , Dexametasona/antagonistas & inibidores , Interferon Tipo I/farmacologia , Interleucina-6/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mieloma Múltiplo/patologia , Fosfatidilinositol 3-Quinases/fisiologia , Células Tumorais Cultivadas/patologia , Idoso , Apoptose/genética , Caspase 3 , Caspases/metabolismo , Dexametasona/toxicidade , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Fator de Crescimento Insulin-Like I/antagonistas & inibidores , Fator de Crescimento Insulin-Like I/biossíntese , Fator de Crescimento Insulin-Like I/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/fisiologia , Mieloma Múltiplo/enzimologia , Fosfatidilinositol 3-Quinases/metabolismo , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/fisiologia , Receptor de Interferon alfa e beta , Receptores de Interferon/fisiologia , Receptores de Interleucina-6/fisiologia , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Células Tumorais Cultivadas/efeitos dos fármacos
14.
Blood ; 96(1): 234-41, 2000 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10891456

RESUMO

Cell migration requires a dynamic interaction between the cell, its substrate, and the cytoskeleton-associated motile apparatus. Integrin-associated protein (IAP)/CD47 is a 50-kd cell surface protein that is physically associated with beta3 integrins and that modulates the functions of beta3 integrins in various cells. However, in B-lymphocytes that express beta1 integrins but few beta3 integrins, the roles of IAP/CD47 remain to be determined. Cross-linking of IAP/CD47 by the immobilized anti-IAP/CD47 monoclonal antibody (mAb) B6H12, but not 2D3, produced signals to promote polarization with lamellipodia, a characteristic morphology during leukocyte migration, in pre-B and mature B-cell lines (BALL, Nalm6, ONHL-1, Daudi), but not in myeloma cell lines (RPMI8226, OPM-2). In the presence of the immobilized fibronectin (FN), soluble B6H12 could increase the rate of the polarization and activate migratory activity of BALL cells to FN in a transwell filter assay. Furthermore, the dominant-negative form of CDC42 completely blocked B6H12-induced morphologic and functional changes without inhibiting phorbol 12-myristate 13-acetate-induced spreading on FN in BALL cells, whereas the dominant-negative form of Rac1 inhibited all these changes. These findings demonstrate that in B-lymphocytes, IAP/CD47 may transduce the signals to activate the migratory activity, in which CDC42 may be specifically involved, and that IAP/CD47 shows synergistic effect with alpha4beta1 on B-cell migration. These findings would provide new insight into the role of IAP/CD47 on B-cell function.


Assuntos
Antígenos CD/fisiologia , Linfócitos B/fisiologia , Proteínas de Transporte/fisiologia , Proteína cdc42 de Ligação ao GTP/metabolismo , Anticorpos Monoclonais/farmacologia , Linfócitos B/citologia , Linfoma de Burkitt , Antígeno CD47 , Polaridade Celular , Reagentes de Ligações Cruzadas , Fibronectinas/fisiologia , Humanos , Integrina beta1/fisiologia , Integrina beta3 , Glicoproteínas da Membrana de Plaquetas/fisiologia , Receptores de Fibronectina/fisiologia , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Transfecção , Células Tumorais Cultivadas
15.
Muscle Nerve ; 23(7): 1076-83, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10883002

RESUMO

Motor unit action potentials (MUPs) recorded by a monopolar needle electrode in normal and neuropathic muscles were computer-simulated. Five experienced electromyographers acted as examiners and assessed the firing sounds of these MUPs without seeing them on a display monitor. They judged whether the sounds were crisp or close enough to accept for the evaluation of MUP parameters and whether, when judged acceptable, they were neuropathic-polyphasic. The examiners recognized motor unit (MU) sound as crisp or polyphasic when the MUP obtained was 0.15-0.2 mm from the edge of the MU territory. When the intensity of the sound decreased, they were unable to perceive it as crisp. When the intensity exceeded the saturation level of loudspeaker output, the sound was perceived as polyphasic, but the wave form of the MUP was not. When the frequency of the neuropathic MUP was lowered, the examiners were unable to determine whether the MUP was polyphasic. MUPs recognized as acceptable for evaluation can be distinguished by listening to MU sounds. The audio amplifier gain must be appropriately adjusted for each MUP amplitude in order to assess whether an individual MU sound is crisp or polyphasic before MUP parameters are measured on a display monitor.


Assuntos
Eletromiografia/métodos , Neurônios Motores/fisiologia , Músculo Esquelético/fisiologia , Doenças Neuromusculares/diagnóstico , Doenças Neuromusculares/fisiopatologia , Adulto , Simulação por Computador , Eletromiografia/instrumentação , Humanos , Potenciais da Membrana/fisiologia , Microcomputadores , Microeletrodos , Fibras Musculares Esqueléticas/fisiologia
16.
Nat Med ; 6(6): 659-66, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10835682

RESUMO

We have identified an interferon-like cytokine, limitin, on the basis of its ability to arrest the growth of or kill lympho-hematopoietic cells. Limitin strongly inhibited B lymphopoiesis in vitro and in vivo but had little influence on either myelopoiesis or erythropoiesis. Because limitin uses the interferon alpha/beta receptors and induces interferon regulatory factor-1, it may represent a previously unknown type I interferon prototype. However, preferential B-lineage growth inhibition and activation of Janus kinase 2 in a myelomonocytic leukemia line have not been described for previously known interferons.


Assuntos
Linfócitos B/citologia , Citocinas/fisiologia , Células-Tronco Hematopoéticas/citologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Medula Óssea/metabolismo , Linhagem Celular Transformada , Clonagem Molecular , Citocinas/análise , Citocinas/genética , DNA Complementar , Proteínas de Ligação a DNA/metabolismo , Feminino , Expressão Gênica , Inibidores do Crescimento/genética , Inibidores do Crescimento/metabolismo , Humanos , Fator Regulador 1 de Interferon , Interferon Tipo I/química , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Dados de Sequência Molecular , Fosfoproteínas/metabolismo , Receptor de Interferon alfa e beta , Receptores de Interferon/genética , Receptores de Interferon/metabolismo , Transdução de Sinais , Baço/metabolismo , Células Tumorais Cultivadas
17.
Schizophr Res ; 42(3): 187-91, 2000 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-10785577

RESUMO

We examined the relationship between event-related potentials and thought disorder in schizophrenia. The subjects were 29 chronic schizophrenic patients. Thought disorder was assessed using the Comprehensive Index of Positive Thought Disorder developed by Harrow and colleagues (Harrow and Quinlan, 1985; Marengo et al., 1986). Auditory event-related potentials were recorded during a standard oddball task. The P300 amplitude correlated negatively with the severity of the thought disorder. The P300 amplitude in the patients with thought disorder was significantly smaller than in the patients without thought disorder. These results suggest that a reduction in P300 amplitude is associated with a fundamental impairment of information processing in schizophrenic patients.


Assuntos
Transtornos Cognitivos/etiologia , Potenciais Evocados P300/fisiologia , Esquizofrenia/complicações , Pensamento/fisiologia , Adulto , Transtornos Cognitivos/diagnóstico , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Índice de Gravidade de Doença
18.
Nihon Rinsho ; 57(6): 1406-9, 1999 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-10391008

RESUMO

We preliminarily describe the frequency of TTV in Japanese pregnant women, non-parenteral, postnatal materno-infantile transmission of TTV, and 2 cases in which infantile development of the TTV carrier-state seemed to have occurred by vertical infection. The sera of 85 hepatitis B, C and G-positive and 36 non-pathological pregnant Japanese women were screened for the presence of TTV DNA with a use of semi-nested PCR. The positive rates were 25.9 and 27.8%, respectively. No significant differences were gained between these two groups. Twenty-one infants were born to the TTV carrier women. Of them, 9 infants (42.9%) sero-converted to TTV DNA-positive after their age of 4 months. Among the infants who were breast-fed, the positive sero-conversion rate of TTV DNA tended to increase as the length of the breast feeding period increased. Serum AST/ALT levels stayed within normal upper limits in the 9 infants. This study indicates the frequent, and furthermore, certain possibility of non-parenteral (i.e., via breast milk), postnatal vertical infection of TTV.


Assuntos
Infecções por Vírus de DNA/transmissão , Vírus de DNA/isolamento & purificação , Hepatite Viral Humana/transmissão , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez , Biomarcadores/análise , Aleitamento Materno , Portador Sadio/virologia , Infecções por Vírus de DNA/epidemiologia , Infecções por Vírus de DNA/virologia , DNA Viral/análise , Feminino , Hepatite Viral Humana/epidemiologia , Hepatite Viral Humana/virologia , Humanos , Lactente , Recém-Nascido , Japão/epidemiologia , Troca Materno-Fetal , Gravidez
19.
J Electromyogr Kinesiol ; 9(3): 201-8, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10328415

RESUMO

A computer simulation was performed to investigate the size index as a motor unit identifier in electromyography. The size index calculated from the amplitude and area of the simulated motor unit action potential (MUP) was plotted against the distance between the needle electrode and current source to show how the index changes as a function of the distance. The index of the MUP also was plotted against the number of muscle fibers belonging to a single motor unit, the size of the motor unit territory, and the diameter of the muscle fibers in order to establish the major determinants of the index. The index was relatively constant for the distance less than 2 mm between the needle electrode and closest edge of the current source. It changed logarithmically with the number of muscle fibers and with the diameter of the fibers.


Assuntos
Simulação por Computador , Eletromiografia/métodos , Potencial Evocado Motor/fisiologia , Músculo Esquelético/fisiologia , Humanos , Fibras Musculares Esqueléticas/fisiologia
20.
Br J Haematol ; 103(3): 804-12, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9858236

RESUMO

Very late antigen (VLA)-4 integrin has been suggested to play an important role in haemopoiesis. However, little is known concerning the roles of the fibronectin (FN)/VLA-4 interaction in the proliferation of human B cells. In this study we investigated the effect of immobilized FN on the proliferation of various B-cell lines, including a newly-established B-cell line, OPM-3, and human tonsillar B cells, that primarily express VLA-4 but not VLA-5. Immobilized FN significantly promoted the proliferation of OPM-3 cells and normal B cells via VLA-4. The cross-linking of beta1 integrins of OPM-3 cells resulted in the phosphorylation of the focal adhesion kinase (FAK) associated 90 kD protein, an increase in FAK-associated kinase activity, and the phosphorylation of Raf-1. Furthermore, the MEK1 inhibitor, PD98059, inhibited the FN-promoted proliferation of OPM-3 cells. These results demonstrate that the FN/VLA-4 interaction transmits the growth signal(s) which may be mediated by Ras pathway in OPM-3 cells, and suggest that OPM-3 cells may be of great value in studying the roles of the FN/VLA-4 interaction in human B-cell growth.


Assuntos
Linfócitos B/patologia , Fibronectinas/metabolismo , Integrinas/metabolismo , Leucemia de Células B/patologia , Receptores de Retorno de Linfócitos/metabolismo , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Divisão Celular , Reagentes de Ligações Cruzadas , Humanos , Integrina alfa4beta1 , Células Tumorais Cultivadas , Tirosina/metabolismo
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