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1.
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.

2.
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
3.
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
4.
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.

6.
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
7.
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.

8.
Biochim Biophys Acta ; 1169(1): 103-6, 1993 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-8334144

RESUMO

Human serum lipoproteins were analyzed by a new modified synthetic boundary cell using an analytical ultracentrifuge. This cell allows the formation of the synthetic boundary at the bottom level of the cell with self-adjusting meniscus and baseline. Thus, the total amount of lipoproteins was seen as a single peak at first. During centrifugation, each component of the lipoproteins was separated according to its flotation characteristics. It was, therefore, possible to determine precisely all lipoprotein components, especially high-density lipoproteins, in the presence of a more rapidly migrating species and to calculate the flotation coefficient of each lipoprotein using the formula for sedimentation coefficient reported by Svedberg (Svedberg, T. (1925) Kolloid-Z. 36, 53-64.


Assuntos
Lipoproteínas/sangue , Ultracentrifugação/instrumentação , Humanos , Lipoproteínas/química , Lipoproteínas HDL/química , Gravidade Específica
9.
Biochim Biophys Acta ; 493(1): 196-200, 1977 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-577886

RESUMO

Aqueous solutions of bovine lung surfactant material were solubilized with a high concentration of sodium deoxycholate and the protein moiety could then be separated from the mixed lipid-sodium deoxycholate micelles by gel filtration in the presence of a micellar concentration of sodium deoxycholate of 10 mM. The lipid-free protein showed only one detectable peak in the gel filtrate and the sedimentation rate of this protein was 12.1 S. Sodium dodecyl sulfate disc gel electrophoresis showed essentially the same pattern as did the protein extracted directly from the bovine lung surfactant material with organic solvents, of which the major component has a molecular weight of 36 000. This protein should be the main apoprotein of lung surfactant material, and the main band in the sodium dodecyl sulfate disc gel electrophoresis, with a molecular weight of 36 000, would constitute the major protein subunit.


Assuntos
Apoproteínas/isolamento & purificação , Ácido Desoxicólico , Pulmão/análise , Surfactantes Pulmonares/isolamento & purificação , Animais , Bovinos , Eletroforese Descontínua , Peso Molecular , Ultracentrifugação
10.
Keio J Med ; 40(4): 235-9, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1803075

RESUMO

Somatosensory vertex potentials (SVPs), consisting of N1, P1, and N2, are obtained widely on the scalp between 100 and 500 msec of latency. To analyze interactions between SVPs evoked by right and left finger stimulation, the sum of N1-P1 or P1-N2 amplitude values in response to stimulation of independent right and left fingers were compared with those evoked by simultaneous stimulation of both fingers. SVPs were recorded at Cz, C3, and C4 in 12 healthy subjects. Three patterns of finger stimulation, namely, right, left, and both right and left, were randomly chosen until 80 responses had been obtained and averaged for each pattern of stimulation. Simultaneous bilateral responses were larger than either right or left finger SVPs. However, they were consistently smaller than summed SVPs from right and left fingers. These results suggest that the SVP generators be different between right and left. But they may be closely inter-related through occlusive connections.


Assuntos
Potenciais Somatossensoriais Evocados/fisiologia , Lateralidade Funcional/fisiologia , Adulto , Humanos , Masculino , Tempo de Reação/fisiologia
11.
Chest ; 95(4): 930-2, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2924632

RESUMO

A 54-year-old woman with the Noonan syndrome was admitted with congestive heart failure and a giant right atrial thrombus with atrial septal defect detected by two-dimensional echocardiography. The thrombus vanished on oral anticoagulant therapy with warfarin. The thrombus is considered to result from hemostasis in the right atrium due to congestive heart failure and to her specific skeletal characteristics. This report describes the first case of Noonan syndrome with right atrial thrombus.


Assuntos
Complexo de Eisenmenger/complicações , Cardiopatias/complicações , Síndrome de Noonan/complicações , Trombose/complicações , Ecocardiografia , Feminino , Átrios do Coração , Cardiopatias/diagnóstico , Humanos , Pessoa de Meia-Idade , Trombose/diagnóstico
12.
J Biochem ; 115(2): 333-7, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7911464

RESUMO

We prepared phospho-tyrosyl glutamine synthetase (P-GS) with suppressed activity from a highly adenylylated glutamine synthetase and applied it to the assay of protein-tyrosine phosphatase (PTPase) present in non-malignant rat liver cells (BRL) by RSV-transformation. The maximum PTPase activity toward P-GS was observed at neutral pH (pH 7.5-8.0) in the soluble and particulate fractions prepared from both BRL and RSV-transformed (RSV-BRL) cells. At low activity levels (< about 0.3 U), the PTPase activity in each fraction was proportional to the sample protein concentration (A280) and the specific activity of PTPase in the soluble fraction of BRL cells was about twofold higher than that in the soluble fraction of BRL cells, while those in particulate fractions of BRL and RSV-BRL cells were almost the same as each other. Soluble fractions of BRL and RSV-BRL were subjected to molecular-sieve and anion-exchange chromatographies. One major PTPase activity, with an M(r) of about 40,000 (40k), was detected in the BRL soluble fraction, and two were detected in the RSV-BRL soluble fraction with M(r)s of about 40k and 60k. The 40k PTPases in BRL and RSV-BRL had the same profiles on anion-exchange chromatography, but the 60k PTPase in RSV-BRL cells showed a different profile. We suggest that the RSV-transformation of BRL cells induced the appearance of the 60k PTPase in the soluble fraction.


Assuntos
Vírus do Sarcoma Aviário/fisiologia , Transformação Celular Viral , Glutamato-Amônia Ligase/metabolismo , Fígado/enzimologia , Proteínas Tirosina Fosfatases/metabolismo , Animais , Linhagem Celular , Linhagem Celular Transformada , Fracionamento Químico , Fígado/citologia , Peso Molecular , Fosforilação , Ratos
13.
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
14.
Int J Hematol ; 60(4): 273-80, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7894031

RESUMO

Protein C has an important role in the regulatory mechanisms of coagulation and fibrinolysis. In patients with heterozygous protein C deficiency, there is an increased risk for thromboembolic disease, especially in the venous system. We describe a patient with protein C deficiency presenting with an acute myocardial infarction (AMI). Direct sequence analysis of the whole protein C gene detected a single base mutation at exon 7; 157 [Arg(CGA) to stop codon (TGA): 6182 C to T]. Thus, the patient was suspected to have a deficiency of the protein C heavy chain molecule, resulting in both a low protein C antigen and activity level. The mutation was also found in the propositus' son and was confirmed by differential termination of the primer extension (DTPE).


Assuntos
Infarto do Miocárdio/etiologia , Deficiência de Proteína C , Proteína C/genética , Sequência de Bases , Códon , Éxons , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação , Análise de Sequência de DNA
15.
Heart ; 80(3): 292-5, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9875091

RESUMO

OBJECTIVE: To investigate cardiac function in patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) and clarify the clinical features of cardiomyopathy in MELAS. PATIENTS: 11 consecutive patients with MELAS (mean age at initial examination 11.3 years, range 4 to 16 years) were enrolled in the study. Six were followed for more than five years. RESULTS: On echocardiographic examination, three patients showed increased left ventricular end diastolic posterior wall thickness (LVPWTd), exceeding 140% of the normal value. Four patients, including these three, had an ejection fraction of less than 50%, and two also had increased left ventricular end diastolic volume (LVEDV) exceeding 140% of the normal value (%N). The LVPWTd%N was correlated positively with the LVEDV%N (R = 0.669, p < 0.05) and negatively with the ejection fraction (R = -0.6701, p < 0.05). One patient died of heart failure aged 22 years. CONCLUSIONS: The cardiomyopathy in MELAS is characterised by an abnormally thick left ventricular wall with progressive dilatation and poor left ventricular contraction developing over several years, indicating hypertrophic cardiomyopathy advancing to dilated cardiomyopathy.


Assuntos
Hipertrofia Ventricular Esquerda/fisiopatologia , Síndrome MELAS/fisiopatologia , Adolescente , Adulto , Criança , Ecocardiografia , Eletrocardiografia , Feminino , Seguimentos , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Síndrome MELAS/diagnóstico por imagem , Masculino , Volume Sistólico
16.
Neurosci Lett ; 253(1): 65-7, 1998 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-9754806

RESUMO

To test the hypothesis that the nerve fiber conduction velocity of a motor unit is correlated with the muscle fiber conduction velocity of the unit, the collision technique was used to discriminate the motor unit action potentials elicited by stimulation of a group of nerve fibers with known conduction velocity. Muscle fiber conduction velocity was determined from the propagating action potentials of the unit recorded by a surface electrode array. A weak but significantly positive correlation was found between nerve and muscle fiber conduction velocities in the thenar muscle of human subjects. The results indicate that the size principle that governs the relation between nerve and muscle fiber size is a fairly weak principle with occasional exceptions.


Assuntos
Nervo Mediano/fisiologia , Neurônios Motores/fisiologia , Fibras Musculares Esqueléticas/fisiologia , Músculo Esquelético/fisiologia , Fibras Nervosas/fisiologia , Potenciais de Ação/fisiologia , Adulto , Estimulação Elétrica , Humanos , Masculino , Músculo Esquelético/inervação , Condução Nervosa/fisiologia
17.
Int J Cardiol ; 59(2): 203-5, 1997 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-9158177

RESUMO

We reported two rare cases of diffuse pulmonary arteriovenous fistulas in infants and children. Both pulmonary angiography and chest computed tomography were obtained and revealed fine network formations clearly, from which the final diagnosis was made.


Assuntos
Fístula Arteriovenosa/diagnóstico por imagem , Pulmão/irrigação sanguínea , Angiografia , Fístula Arteriovenosa/fisiopatologia , Capilares , Pré-Escolar , Cianose/fisiopatologia , Oxigenação por Membrana Extracorpórea , Evolução Fatal , Feminino , Humanos , Lactente , Masculino , Tomografia Computadorizada por Raios X
18.
Brain Dev ; 17(2): 139-41; discussion 144-5, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7625550

RESUMO

We report the 3rd case in the literature of a 3-year-old boy with D-2-hydroxyglutaric (D-2-HG) aciduria, who presented primarily generalized hypotonia and feeding difficulty during the neonatal period, with eventual development of generalized myoclonic seizures. Gas chromatographic analysis of urinary organic acids showed persistent excretion of D-2-HG. The clinical manifestations are quite similar to those of the 2nd reported case with D-2-HG aciduria. Serial MRI performed 1 year and 2 1/2 years after birth demonstrated bilateral symmetrical periventricular lesions in the parieto-occipital white matter, which might reflect the cortical blindness in our patient.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/fisiopatologia , Encéfalo/patologia , Glutaratos/urina , Convulsões/fisiopatologia , Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Erros Inatos do Metabolismo dos Aminoácidos/urina , Cegueira/fisiopatologia , Cromatografia Gasosa , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Convulsões/urina
19.
Spine (Phila Pa 1976) ; 13(3): 257-66, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3388111

RESUMO

Fifty-four patients were treated by a standardized single stage anterior opening wedge and a posterior closing extension wedge osteotomy for back pain associated with postoperative loss of lumbar lordosis (iatrogenic flat back syndrome). Presenting complaints were fatigue, pain and a stooped posture. Etiological factors were, in descending order of frequency, distraction instrumentation with the lower end at the L5 or S1 vertebra, thoracolumbar junction kyphosis greater than 15 degrees, especially if associated with a hypokyphotic thoracic spine, and degenerative changes above and below a previous fusion. Kostuik-Harrington instrumentation was used anteriorly for the opening wedge and Dwyer cables and screws together with a midline plate were used posteriorly for the closing extension osteotomy. Malunion occurred in three patients, one requiring recorrection. Pain relief occurred in 48 (90%). Neurological complications occurred in two patients, one with permanent deficient. Follow-up averaged 4 years. Average preosteotomy lordosis L1-S1 was 21.5 degrees and was restored to 49 degrees (equal to the lordosis before the initial surgery) for an average correction of 29 degrees, (range 24 degrees to 63 degrees). Prevention of this complication can be accomplished by maintaining normal lordosis at the time of initial surgery.


Assuntos
Doença Iatrogênica , Cifose/cirurgia , Osteotomia , Adolescente , Adulto , Idoso , Avaliação da Deficiência , Desenho de Equipamento , Feminino , Humanos , Cifose/diagnóstico por imagem , Cifose/fisiopatologia , Região Lombossacral , Masculino , Pessoa de Meia-Idade , Dispositivos de Fixação Ortopédica , Período Pós-Operatório , Postura , Radiografia , Fusão Vertebral
20.
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
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