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1.
Phys Rev Lett ; 131(10): 101002, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37739367

RESUMO

We report the first result of a direct search for a cosmic axion background (CaB)-a relativistic background of axions that is not dark matter-performed with the axion haloscope, the Axion Dark Matter eXperiment (ADMX). Conventional haloscope analyses search for a signal with a narrow bandwidth, as predicted for dark matter, whereas the CaB will be broad. We introduce a novel analysis strategy, which searches for a CaB induced daily modulation in the power measured by the haloscope. Using this, we repurpose data collected to search for dark matter to set a limit on the axion photon coupling of a CaB originating from dark matter cascade decay via a mediator in the 800-995 MHz frequency range. We find that the present sensitivity is limited by fluctuations in the cavity readout as the instrument scans across dark matter masses. Nevertheless, we suggest that these challenges can be surmounted using superconducting qubits as single photon counters, and allow ADMX to operate as a telescope searching for axions emerging from the decay of dark matter. The daily modulation analysis technique we introduce can be deployed for various broadband rf signals, such as other forms of a CaB or even high-frequency gravitational waves.

2.
Phys Rev Lett ; 127(25): 257001, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-35029441

RESUMO

The Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state, characterized by Cooper pairs condensed at finite momentum, has been a long-sought state that remains unresolved in many classes of fermionic systems, including superconductors and ultracold atoms. A fascinating aspect of the FFLO state is the emergence of periodic nodal planes in real space, but its observation is still lacking. Here we investigate the superconducting order parameter at high magnetic fields H applied perpendicular to the ab plane in a high-purity single crystal of FeSe. The heat capacity and magnetic torque provide thermodynamic evidence for a distinct superconducting phase at the low-temperature/high-field corner of the phase diagram. Despite the bulk superconductivity, spectroscopic-imaging scanning tunneling microscopy performed on the same crystal demonstrates that the order parameter vanishes at the surface upon entering the high-field phase. These results provide the first demonstration of a pinned planar node perpendicular to H, which is consistent with a putative FFLO state.

3.
J Synchrotron Radiat ; 21(Pt 1): 268-72, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24365948

RESUMO

The newly installed BL28XU beamline at SPring-8 is dedicated to in situ structural and electronic analysis of rechargeable batteries. It supports the time range (1 ms to 100 s) and spatial range (1 µm to 1 mm) needed for battery analysis. Electrochemical apparatus for battery charging and discharging are available in experimental hutches and in a preparation room. Battery analysis can be carried out efficiently and effectively using X-ray diffraction, X-ray absorption fine-structure analysis and hard X-ray photoelectron spectroscopy. Here, the design and performance of the beamline are described, and preliminary results are presented.

4.
J Nutr Health Aging ; 27(11): 946-952, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37997714

RESUMO

OBJECTIVES: Accumulating evidence from cross-sectional studies suggests that the serum creatinine-to-cystatin C ratio (CCR) may be a useful biomarker for sarcopenia. This study aimed to assess the cross-sectional and longitudinal associations of CCR with sarcopenia and its parameters in community-dwelling older adults. DESIGN: Cross-sectional and longitudinal study. SETTING AND PARTICIPANTS: This 6-year prospective cohort study included the repeated measurement data from 1,253 Japanese residents (662 males and 591 females) aged ≥65 years who underwent medical checkups in Kusatsu and Hatoyama, Japan. A total of 4,421 observations were collected. MEASUREMENTS: The CCR was grouped into quartiles by sex (Q1-Q4) using Q4 as the reference category. Sarcopenia was defined according to the Asian Working Group for Sarcopenia 2019 algorithm. Skeletal muscle mass index (SMI) measured using segmental multifrequency bioelectrical impedance analysis, handgrip strength (HGS), usual gait speed (UGS), and maximal gait speed (MGS) were measured repeatedly as sarcopenia parameters. The association of the CCR with changes in sarcopenia, SMI, HGS, UGS, and MGS during the 6-year period were analyzed using a generalized linear mixed-effects model. RESULTS: The prevalence of sarcopenia at baseline was 13.1% (11.9% in males and 14.5% in females). In a cross-sectional analysis, the CCR quartile was inversely associated with sarcopenia and was positively associated with SMI, HGS, and MGS (P for trend < 0.001). In a longitudinal analysis during the 6 years, a significant increase in sarcopenia in Q2 (B = 1.1% point/year; P = 0.026 for group-by-time interaction) and significant declines in SMI (B = -0.01 kg/m2/year; P = 0.044 for group-by-time interaction) and MGS (B = -0.008 m/sec/year; P = 0.041 for group-by-time interaction) in Q1 were observed compared with Q4. However, the dose-response relationship was significant only for MGS (P = 0.033 for trend). No significant group-by-time interaction was observed for HGS. CCR was not significantly associated with UGS either cross-sectionally or longitudinally. CONCLUSIONS: CCR is a useful biomarker regarding the status of sarcopenia. It may be used for sarcopenia screening even in older adults whose physical function is difficult to assess. However, further longitudinal studies are needed to determine whether CCR can be a predictor of future sarcopenia.


Assuntos
Sarcopenia , Masculino , Feminino , Humanos , Idoso , Sarcopenia/epidemiologia , Sarcopenia/diagnóstico , Estudos Longitudinais , Creatinina , Estudos Transversais , Força da Mão , Estudos Prospectivos , Cistatina C , Biomarcadores
5.
Med Phys ; 39(7): 4414-22, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22830774

RESUMO

PURPOSE: The purpose of this study is to propose a microfocus x-ray imaging technique for observing the internal structure of small radioactive sources and evaluating geometrical errors quantitatively, and to apply this technique to traceable pointlike (22)Na sources, which were designed for positron emission tomography calibration, for the purpose of quality control of the pointlike sources. METHODS: A microfocus x-ray imaging system with a focus size of 0.001 mm was used to obtain projection x-ray images and x-ray CT images of five pointlike source samples, which were manufactured during 2009-2012. The obtained projection and tomographic images were used to observe the internal structure and evaluate geometrical errors quantitatively. Monte Carlo simulation was used to evaluate the effect of possible geometrical errors on the intensity and uniformity of 0.511 MeV annihilation photon pairs emitted from the sources. RESULTS: Geometrical errors were evaluated with sufficient precision using projection x-ray images. CT images were used for observing the internal structure intuitively. As a result, four of the five examined samples were within the tolerance to maintain the total uncertainty below ±0.5%, given the source radioactivity; however, one sample was found to be defective. CONCLUSIONS: This quality control procedure is crucial and offers an important basis for using the pointlike (22)Na source as a basic calibration tool. The microfocus x-ray imaging approach is a promising technique for visual and quantitative evaluation of the internal geometry of small radioactive sources.


Assuntos
Imagens de Fantasmas/normas , Radiografia/instrumentação , Radiografia/normas , Radioisótopos de Sódio/análise , Radioisótopos de Sódio/normas , Desenho de Equipamento , Análise de Falha de Equipamento , Japão , Compostos Radiofarmacêuticos/análise , Compostos Radiofarmacêuticos/normas , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Nature ; 436(7050): 499-503, 2005 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-16049478

RESUMO

The detection of electron antineutrinos produced by natural radioactivity in the Earth could yield important geophysical information. The Kamioka liquid scintillator antineutrino detector (KamLAND) has the sensitivity to detect electron antineutrinos produced by the decay of 238U and 232Th within the Earth. Earth composition models suggest that the radiogenic power from these isotope decays is 16 TW, approximately half of the total measured heat dissipation rate from the Earth. Here we present results from a search for geoneutrinos with KamLAND. Assuming a Th/U mass concentration ratio of 3.9, the 90 per cent confidence interval for the total number of geoneutrinos detected is 4.5 to 54.2. This result is consistent with the central value of 19 predicted by geophysical models. Although our present data have limited statistical power, they nevertheless provide by direct means an upper limit (60 TW) for the radiogenic power of U and Th in the Earth, a quantity that is currently poorly constrained.

7.
J Nutr Health Aging ; 24(3): 282-289, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32115609

RESUMO

OBJECTIVES: To identify the dietary patterns among community-dwelling Japanese older adults and to explore the association between these patterns and sarcopenia. DESIGN: Cross-sectional study. SETTING: Kashiwa city, Chiba prefecture, Japan. PARTICIPANTS: Community-dwelling older adults (n = 1241) aged 65 years and over who were not eligible for long-term care. MEASUREMENTS: Dietary intake was assessed using the brief self-administered diet history questionnaire (BDHQ). Dietary patterns were identified using both principal component analysis and the score on the Japanese diet comprising soybeans and soybean products, fish, vegetables, pickles, mushroom, seaweeds, and fruits. Sarcopenia was defined by the Asian Working Group for Sarcopenia (AWGS) criteria. A binary logistic regression analysis was performed with sarcopenia status as the dependent variable after adjusting for economic status, living alone status, BMI, energy intake, multimorbidity, and physical activity. RESULTS: Participants' mean age was 74.6 years, and 52.1% were male. According to AWGS criteria, 5.1% had sarcopenia. Three dietary patterns were identified from the principal component analysis. Dietary pattern 1 (DP1), showed high loadings for fish, tofu, vegetables, and fruits which are similar to the side dishes in a typical Japanese diet. Dietary pattern 2 (DP2) had high factor loadings for fish, rice, and miso soup which are main dishes in a typical Japanese diet. Dietary pattern 3 (DP3) had a high factor loading for noodles. Men with the lowest tertile of DP1 score had a higher likelihood of being sarcopenic (Adjusted odds ratio (AOR) 3.67, 95% confidence interval (CI) 1.20-11.2). Women with the lowest tertile of DP2 score had a moderate likelihood of being sarcopenic (AOR 2.71, 95%CI 0.99-7.46). Low adherence to Japanese dietary pattern was associated with prevalence of sarcopenia in both genders. CONCLUSION: Adherence to a dietary pattern high in foods characteristic of a Japanese diet including fish, soybean products, vegetables, and fruits was associated with low prevalence of sarcopenia in both genders.


Assuntos
Dieta/efeitos adversos , Sarcopenia/induzido quimicamente , Idoso , Animais , Estudos Transversais , Feminino , Humanos , Vida Independente , Japão , Masculino
8.
Kyobu Geka ; 62(2): 136-9, 2009 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-19202935

RESUMO

A rare case of recurrent Castleman disease is reported. A 49-year-old man was referred to our division under the suspicion of mediastinal tumor. We performed tumor resection successfully, and the tumor was shown to be Castleman disease by histology. The patient had a past history of this disease, therefore it was suggested that the tumor recurred at the same site 20-years after removal.


Assuntos
Hiperplasia do Linfonodo Gigante/diagnóstico , Hiperplasia do Linfonodo Gigante/cirurgia , Hiperplasia do Linfonodo Gigante/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Tempo
9.
Kyobu Geka ; 62(7): 527-34, 2009 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-19588821

RESUMO

Airway obstruction due to compression by the thoracic great vessels or their branches sometimes appears in patients with congenital heart disease. However, to make a definitive diagnosis may not be easy, because respiratory symptoms are common and stem from a variety of causes in this cohort. Thus, some invasive evaluation, including angiography, bronchial fiberscopy, and bronchography has usually been required. We employed multi-slice helical computed tomography (MSCT) and 3-dimensional (3D) image reconstruction in 7 cases (median age, 107 days ; range, 21 days to 6 years) who were suspected of complicating external vascular compression as a cause of respiratory symptoms. The CT scan clearly showed detailed anatomy of the thoracic vessels and interrelationship with the airway systems. It also disclosed a culprit artery compressing the trachea or bronchus. Different from other invasive or noninvasive examination modalities, MSCT allows precise evaluation of 2 independent organ systems, such as vascular and respiratory systems. We conclude that MSCT with 3D image reconstruction represents a reliable less-invasive technique for assessment of symptomatic airway obstruction caused by vascular compression.


Assuntos
Obstrução das Vias Respiratórias/diagnóstico por imagem , Aorta Torácica/anormalidades , Tomografia Computadorizada Espiral , Obstrução das Vias Respiratórias/etiologia , Criança , Feminino , Humanos , Imageamento Tridimensional , Lactente , Recém-Nascido , Masculino
10.
Kyobu Geka ; 62(7): 560-3, 2009 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-19588827

RESUMO

A 77-year-old woman was transferred as traumatic thoracic aortic dissection with subarachnoid hemorrhage soon after a traffic accident. Her consciousness was slightly compromised and cardiogenic shock was developed. Serial computed tomography (CT) scans revealed an unchanging subarachnoid hemorrhage and a progressive mediastinal hemorrhage and pericardial effusion due to traumatic type B aortic dissection. An emergency distal arch replacement was performed under cardiopulmonary bypass 4 hours after the injury. She woke up 3 days after the operation without progression of subarachnoid hemorrhage on a cerebral CT scan. She was discharged 36 days after the injury.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Hemorragia Subaracnóidea/complicações , Traumatismos Torácicos/complicações , Acidentes de Trânsito , Idoso , Dissecção Aórtica/etiologia , Aneurisma da Aorta Torácica/etiologia , Emergências , Feminino , Humanos , Hemorragia Subaracnóidea/etiologia
11.
Nat Commun ; 10(1): 3282, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31337758

RESUMO

The pseudogap phenomenon in the cuprates is arguably the most mysterious puzzle in the field of high-temperature superconductivity. The tetragonal cuprate HgBa2CuO4+δ, with only one CuO2 layer per primitive cell, is an ideal system to tackle this puzzle. Here, we measure the magnetic susceptibility anisotropy within the CuO2 plane with exceptionally high-precision magnetic torque experiments. Our key finding is that a distinct two-fold in-plane anisotropy sets in below the pseudogap temperature T*, which provides thermodynamic evidence for a nematic phase transition with broken four-fold symmetry. Surprisingly, the nematic director orients along the diagonal direction of the CuO2 square lattice, in sharp contrast to the bond nematicity along the Cu-O-Cu direction. Another remarkable feature is that the enhancement of the diagonal nematicity with decreasing temperature is suppressed around the temperature at which short-range charge-density-wave formation occurs. Our result suggests a competing relationship between diagonal nematic and charge-density-wave order in HgBa2CuO4+δ.

12.
Kyobu Geka ; 61(2): 147-51, 2008 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-18268954

RESUMO

A 84-year-old woman presented with abdominal pain and tarry stools. She was admitted to our hospital, and colonofiberscopy showed type II tumor located cecum. We prevented deep vein thrombosis and acute pulmonary embolism (APE) after abdominal surgery by using the elastic stockings and intermittent pneumatic compression system in operation room. She underwent ileocecal resection and lymphonodi dissection (D2). On 2nd postoperative day, she complained of sudden respiratory distress with loss of consciousness and went into the state of shock. We made the diagnosis of APE after reviewing chest computed tomography and cardiac echo. An emergency atrial and pulmonary thromboembolectomy under cardiopulmonary bypass was performed. We removed the thrombus from right atrium and bilateral main pulmonary artery. After operation, we inserted a temporary vena cava filter into vena cava. We performed the anticoagulant therapy by continuous infusion of heparin with assisting respiration by respirator. The pulmonary artery pressure became steady about 25 approximately 30 mmHg. On 14th postoperative day, we extubated tracheotube. On 40th postoperative day, she could discharge from hospital on foot. Early diagnosis and prompt treatment for APE are important, and we should always keep APE in mind after abdominal surgery.


Assuntos
Neoplasias do Ceco/cirurgia , Complicações Pós-Operatórias , Embolia Pulmonar/terapia , Trombectomia , Doença Aguda , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Procedimentos Cirúrgicos do Sistema Digestório , Diagnóstico Precoce , Emergências , Feminino , Átrios do Coração , Heparina/administração & dosagem , Humanos , Dispositivos de Compressão Pneumática Intermitente , Artéria Pulmonar , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/prevenção & controle , Meias de Compressão , Resultado do Tratamento , Filtros de Veia Cava , Trombose Venosa/prevenção & controle
13.
Minerva Chir ; 62(2): 129-32, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17353855

RESUMO

We report a very rare case of an infant with viscero-atrial situs inversus presenting mirror image Berry syndrome (aortopulmonary window, interrupted aortic arch, anomalous origin of the left pulmonary artery, and intact ventricular septum). Successful surgical treatment was accomplished 56 days following the initial rescue bilateral pulmonary artery banding.


Assuntos
Anormalidades Múltiplas/cirurgia , Aorta Torácica/cirurgia , Defeito do Septo Aortopulmonar/cirurgia , Cardiopatias Congênitas/cirurgia , Artéria Pulmonar/cirurgia , Situs Inversus/cirurgia , Anormalidades Múltiplas/diagnóstico , Aorta Torácica/anormalidades , Defeito do Septo Aortopulmonar/diagnóstico , Procedimentos Cirúrgicos Cardíacos/métodos , Feminino , Cardiopatias Congênitas/diagnóstico , Humanos , Recém-Nascido , Artéria Pulmonar/anormalidades , Situs Inversus/diagnóstico , Síndrome , Resultado do Tratamento
14.
J Prev Alzheimers Dis ; 4(2): 93-99, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29186279

RESUMO

BACKGROUND: Cognitive function can substantially decline over a long period, and understanding the trajectory of cognitive function is important. However, little is known about the linkage between nutritional biomarkers and long-term cognitive change. OBJECTIVES: We analyzed 13-year longitudinal data for older Japanese to examine the associations of serum albumin and hemoglobin levels with the trajectory of cognitive function. DESIGN: Longitudinal study. SETTING: Community-based. PARTICIPANTS: A total of 1,744 community-dwelling adults aged 65 years or older who participated in annual health examinations in Kusatsu town, Gunma Prefecture, Japan, from 2002-2014. MEASUREMENTS: Cognitive function was assessed annually by the Mini-Mental State Examination (MMSE). Albumin and hemoglobin levels at baseline (the year when a respondent first participated in the health examination) were divided into quartiles. Hierarchical linear modeling was used to analyze intrapersonal and interpersonal differences in cognitive function. RESULTS: Participants' MMSE scores decreased at an accelerated rate over the 13-year period. Participants with the lowest baseline albumin level (below the first quartile line) showed a greater accelerated decline in MMSE scores over time, compared with those with the highest level (above the third quartile line). Moreover, MMSE scores in participants with a lower hemoglobin level and lower MMSE score at baseline tended to decline faster over time at an accelerated rate. CONCLUSIONS: These findings yield new insights about the complex and diverse roles of these nutritional biomarkers on the trajectory of cognitive function in old age.


Assuntos
Cognição , Disfunção Cognitiva/sangue , Hemoglobinas/análise , Albumina Sérica/análise , Idoso , Biomarcadores/sangue , Cognição/fisiologia , Progressão da Doença , Humanos , Vida Independente , Japão , Modelos Lineares , Estudos Longitudinais , Testes de Estado Mental e Demência , Fatores de Tempo
15.
J Nutr Health Aging ; 21(1): 11-16, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27999844

RESUMO

OBJECTIVES: To examine associations of dietary variety with changes in lean mass and physical performance during a 4-year period in an elderly Japanese population. DESIGN: Four-year prospective study. SETTING: The Hatoyama Cohort Study and Kusatsu Longitudinal Study, Japan. PARTICIPANTS: 935 community-dwelling Japanese aged 65 years or older. MEASUREMENTS: Dietary variety was assessed using a 10-item food frequency questionnaire. Body composition was determined by multifrequency bioelectrical impedance analysis, and physical performance (grip strength and usual gait speed) was measured in surveys at baseline and 4 years later. Longitudinal analysis included only participants who were originally in the upper three quartiles of lean body mass, appendicular lean mass, grip strength, and usual gait speed. The outcome measures were decline in lean body mass, appendicular lean mass, grip strength, and usual gait speed, defined as a decrease to the lowest baseline quartile level at the 4-year follow-up survey. Associations of dietary variety with the outcome measures were examined by logistic regression analysis adjusted for potential confounders. RESULTS: In the fully adjusted model, the odds ratios for decline in grip strength and usual gait speed were 0.43 (95% confidence interval, 0.19-0.99) and 0.43 (confidence interval, 0.19-0.99), respectively, for participants in the highest category of dietary variety score as compared with those in the lowest category. Dietary variety was not significantly associated with changes in lean body mass or appendicular lean mass. CONCLUSION: Among older adults, greater dietary variety may help maintain physical performance, such as grip strength and usual gait speed, but not lean mass.


Assuntos
Índice de Massa Corporal , Dieta , Aptidão Física , Idoso , Povo Asiático , Composição Corporal , Feminino , Seguimentos , Marcha , Força da Mão , Humanos , Japão , Modelos Logísticos , Estudos Longitudinais , Masculino , Avaliação Nutricional , Estudos Prospectivos , Inquéritos e Questionários
16.
J Nutr Health Aging ; 20(7): 691-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27499301

RESUMO

OBJECTIVES: To examine the associations of dietary variety with body composition and physical function in community-dwelling elderly Japanese. DESIGN: Cross-sectional study. SETTING: Community-based. PARTICIPANTS: A total of 1184 community-dwelling elderly adults aged 65 and over. MEASUREMENTS: Dietary variety was assessed with a food frequency questionnaire (maximum, 10 points) that encompassed the 10 main food components of Japanese meals (meat, fish/shellfish, eggs, milk, soybean products, green/yellow vegetables, potatoes, fruit, seaweed, and fats/oils). Body composition was determined by multifrequency bioelectrical impedance analysis. Physical function was assessed by measuring grip strength and usual walking speed. Multiple linear regression analysis was used to examine the associations of dietary variety with body composition and physical function. RESULTS: After adjusting for potential confounders, higher dietary variety scores were independently associated with higher lean mass (ß (SE): 0.176 (0.049), p<0.001) and appendicular lean mass (ß (SE): 0.114 (0.027), p<0.001) but not with body fat mass. Elders with a higher dietary variety score had greater grip strength and faster usual walking speed (ß (SE): 0.204 (0.071), p=0.004, and ß (SE): 0.008 (0.003), p=0.012, respectively). CONCLUSION: Greater dietary variety was significantly associated with greater lean mass and better physical function in Japanese elders. The causal relationship warrants investigation in a prospective study.


Assuntos
Composição Corporal/fisiologia , Dieta , Aptidão Física/fisiologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Laticínios , Inquéritos sobre Dietas , Feminino , Frutas , Força da Mão , Humanos , Vida Independente , Japão , Masculino , Carne , Verduras , Caminhada
17.
Biochim Biophys Acta ; 952(1): 37-47, 1988 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-3422029

RESUMO

Monoclonal antibodies were raised against human thrombin-antithrombin III complex by a hybridoma technique. Among them, five monoclonal antibodies, designated as JITAT-4, -14, -16, -17 and -19, were found to react with thrombin-antithrombin III, but not with its nascent components, alpha-thrombin or antithrombin III. Their respective immunoglobulin classes are IgG1 for JITAT-16 and -19, and IgG2a for JITAT-4, -14 and -17. Besides the thrombin-antithrombin III complex, they all bound to the Factor Xa-antithrombin III complex and the active-site-cleaved two-chain antithrombin III as well. Moreover, the reactivity of these two antibodies to the neoantigens was not affected by heparin, suggesting that their epitopes are independent of heparin-induced conformational changes of antithrombin III. Two of them, JITAT-16 and -17, were categorized as high-affinity antibodies to thrombin-antithrombin III complex, the dissociation constants being 6.7 nM and 4.8 nM, respectively. However, they do not share antigenic determinants. These monoclonal antibodies may allow us to explore more precisely the reaction between antithrombin III and thrombin or its related enzymes.


Assuntos
Antitrombina III/metabolismo , Trombina/metabolismo , Anticorpos Monoclonais , Complexo Antígeno-Anticorpo , Antitrombina III/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Fator Xa , Humanos , Imunoglobulina G , Cinética , Ligação Proteica , Serina Endopeptidases/metabolismo , Trombina/imunologia
18.
Biochim Biophys Acta ; 1232(3): 208-16, 1995 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-8534673

RESUMO

A Photosystem II (PS II) complex was purified from an acidophilic as well as a thermophilic red alga, Cyanidium caldarium. The purified PS II complex was essentially devoid of phycobiliproteins and other contaminating components, and showed a high oxygen-evolving activity of 2375 mumol O2/mg Chl per h using phenyl-p-benzoquinone as the electron acceptor. The expression of this high activity did not require addition of exogenous Ca2+, although EDTA reduced the activity by 40%. This effect of EDTA can be reversed not only by Ca2+ but also by Mg2+; a similar Mg2+ effect has been observed in purified cyanobacterial PS II but not in higher plant PS II. Immunoblotting analysis indicated the presence of major intrinsic polypeptides commonly found in PS II from cyanobacteria and higher plants as well as the extrinsic 33 kDa protein. Antibodies against the extrinsic 23 and 17 kDa proteins of higher plant PS II, however, did not crossreact with any polypeptides in the purified PS II, indicating the absence of these proteins in the red alga. In contrast, two other extrinsic proteins of 17 and 12 kDa were present in the red algal PS II; they were released by 1 M Tris or Urea/NaCl treatment but not by 1 M NaCl. The 17 kDa polypeptide was identified to be cytochrome c-550 from heme-staining, immunoblot analysis and N-terminal amino acid sequencing, and the 12 kDa protein was found to be homologous to the 12 kDa extrinsic protein of cyanobacterial PS II from its N-terminal sequence. These results indicate that PS II from the red alga is closely related to PS II from cyanobacteria rather than to that from higher plants, and that the replacement of PS II extrinsic cytochrome c-550 and the 12 kDa protein by the extrinsic 23 and 17 kDa proteins occurred during evolution from red algae to green algae and higher plants.


Assuntos
Grupo dos Citocromos c/análise , Complexo de Proteínas do Centro de Reação Fotossintética/isolamento & purificação , Proteínas de Plantas/análise , Rodófitas/química , Sequência de Aminoácidos , Cloroplastos/química , Cianobactérias/química , Grupo dos Citocromos c/química , Concentração de Íons de Hidrogênio , Magnésio/metabolismo , Dados de Sequência Molecular , Peso Molecular , Oxigênio/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/química , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Complexo de Proteína do Fotossistema II , Proteínas de Plantas/química , Análise de Sequência
19.
J Am Coll Cardiol ; 15(1): 131-9, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2295722

RESUMO

Blood flow in bypass grafts and recipient left anterior descending coronary arteries was evaluated with combined two-dimensional and Doppler echocardiography in 15 patients with an internal mammary artery graft and in 24 patients with a saphenous vein graft. Comparative studies of coronary hemodynamics were also performed regarding these two different grafting techniques. The graft vessel was detected in 11 (79%) of 14 patients with an internal mammary artery graft and in 20 (87%) of 23 with a saphenous vein graft. The recipient left anterior descending coronary artery was detected in 10 (67%) of the former group and 17 (71%) of the latter. The blood flow patterns obtained were generally biphasic, consisting of systolic and diastolic phases with higher velocity during diastole. The maximal diastolic flow velocity in internal mammary artery grafts was much higher than that in saphenous vein grafts. In patients with an internal mammary artery graft, the flow pattern characteristics within the recipient coronary artery were quite similar to those within the arterial graft, and flow velocities within the recipient coronary artery and the arterial graft were quantitatively almost identical. This outcome may contribute to the long-term patency seen in internal mammary artery grafts. On the other hand, the flow velocity in saphenous vein grafts was fairly low throughout the cardiac cycle. Flow velocity in the recipient coronary artery in patients with a saphenous vein graft was accelerated only in early diastole. As a result, the recipient coronary artery flow pattern and velocity differed substantially from those in the saphenous vein graft.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ponte de Artéria Coronária , Circulação Coronária/fisiologia , Ecocardiografia Doppler , Ecocardiografia , Anastomose de Artéria Torácica Interna-Coronária , Veia Safena/transplante , Velocidade do Fluxo Sanguíneo , Doença das Coronárias/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/fisiologia , Grau de Desobstrução Vascular
20.
J Bone Miner Res ; 13(9): 1370-7, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9738508

RESUMO

Aging is associated with an increase in bone marrow adipose tissue and a reduction in bone turnover. The P6 strain of senescence-accelerated mice (SAM) exhibit an early decrease in bone mass with a reduction in bone remodeling. In the bone marrow, suppressed osteoblastogenesis and osteoclastogenesis with enhanced adipogenesis are observed. The present study was undertaken to clarify the mechanism of age-related changes in bone turnover using bone marrow cells from SAMP6 mice. Because interleukin (IL)-11 has been shown to potently inhibit adipogenesis and to stimulate osteoclast formation, the effect of IL-11 on the differentiation of bone marrow cells was examined. The impaired formation of both osteoblasts and osteoclasts was restored and the enhanced formation of adipocytes was suppressed by the addition of 10 pM recombinant human IL-11. Other cytokines that activate gp130 as a common signal transducer, IL-6 and leukemia inhibitory factor, did not have such effects. Sequence analysis of the entire coding region of IL-11 cDNA obtained from SAMP6 stromal cells revealed no mutations. Constitutively secreted IL-11 protein into culture media, and its mRNA expression stimulated by transforming growth factor beta were reduced in stromal cells from SAMP6 compared with those in control mice. These results demonstrate that the expression of IL-11 is reduced in bone marrow cells of SAMP6 and suggest that the reduction in IL-11 actions is involved in the impairment of both osteoblastogenesis and osteoclastogenesis in these mice. There is a possibility that alterations in IL-11 actions may be associated with the age-related impairment in bone metabolism.


Assuntos
Tecido Adiposo/metabolismo , Envelhecimento/patologia , Doenças Ósseas Metabólicas/etiologia , Células da Medula Óssea/metabolismo , Interleucina-11/biossíntese , Interleucina-6 , Tecido Adiposo/citologia , Tecido Adiposo/efeitos dos fármacos , Envelhecimento/metabolismo , Animais , Antígenos CD/biossíntese , Antígenos CD/genética , Densidade Óssea/fisiologia , Doenças Ósseas Metabólicas/patologia , Células da Medula Óssea/efeitos dos fármacos , Remodelação Óssea/fisiologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultura , Receptor gp130 de Citocina , DNA Complementar/análise , Inibidores do Crescimento/biossíntese , Humanos , Interleucina-11/genética , Interleucina-11/farmacologia , Fator Inibidor de Leucemia , Linfocinas/biossíntese , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/genética , Camundongos , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/fisiologia
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