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1.
Child Dev ; 94(4): 865-873, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36752147

RESUMEN

Since robots are becoming involved in children's lives, it is urgent to determine how children perceive robots. The present study assessed whether Japanese 5-year-olds care about their reputation when interacting with a social robot. Children were given stickers and asked to divide them between themselves and an absent recipient. Results revealed that children (N = 112, 55 boys, 57 girls) strategically shared more stickers when being watched by a social interactive robot than by an attentional but non-interactive robot or a still robot. Additionally, children (N = 36, 18 boys, 18 girls) attributed higher psychological properties to social robots. This study is the first to show that 5-year-olds care about their reputations from social robots.


Asunto(s)
Robótica , Masculino , Femenino , Humanos , Niño , Preescolar , Robótica/métodos , Interacción Social
2.
J Artif Organs ; 26(2): 127-133, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35776247

RESUMEN

Few reports have examined the association between changes in cerebral oxygenation and clinical factors, including blood pressure (BP), upon standing after hemodialysis (HD). This study aimed to clarify the factors affecting the changes in cerebral regional oxygen saturation (rSO2) upon standing after HD and monitor the differences in cerebral rSO2 changes that occur upon standing after HD in patients with and without diabetes mellitus (DM). Changes in mean BP and cerebral rSO2 were tracked in 43 HD patients during 120 s of standing after HD using an INVOS 5100c oxygen saturation monitor. The post-HD cerebral rSO2 at rest was 55.8 ± 10.2%, while that at 120 s of standing decreased to 51.9 ± 9.6%; therefore, the percentage change in cerebral rSO2 at 120 s of standing was - 6.8 ± 6.4%, which was significantly lower than before HD (p < 0.001). This change was significantly correlated with the presence of DM, HD duration, mean BP at 120 s of standing, and percentage change in mean BP at 120 s of standing. A multivariable linear regression analysis showed that percentage change in cerebral rSO2 at 120 s of standing was independently associated with the percentage change in mean BP at 120 s of standing (standardized coefficient: 0.432; p = 0.004). Furthermore, there were significant decreases in percentage changes in cerebral rSO2 throughout the standing period in HD patients with versus without DM. Therefore, cerebral oxygenation deterioration upon standing after HD should receive attention, particularly in HD patients with DM.


Asunto(s)
Diabetes Mellitus , Diálisis Renal , Humanos , Oxígeno , Presión Sanguínea , Encéfalo
3.
Heart Vessels ; 37(11): 1947-1956, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35569067

RESUMEN

PURPOSE: For patients with aortic dissection (AD) and intramural hematoma (IMH), the optimal cardiac phase to detect intimal tears (IT) and ulcer-like projections (ULP) on retrospective electrocardiogram (ECG)-gated computed tomography angiography (CTA) remains unclear. The purpose of this study was to compare the accuracy of retrospective ECG-gated CTA for detecting IT in AD and ULP in IMH between each cardiac phase. MATERIALS AND METHODS: A total of 75 consecutive patients with AD and IMH of the thoracic aorta were enrolled in this single-center retrospective study. The diagnostic performance to detect IT and ULP in the thoracic aortic regions (including the ascending aorta, aortic arch, and proximal and distal descending aorta) was compared in each cardiac phase on retrospective ECG-gated CTA. RESULTS: In the systolic phase (20%), the accuracy, sensitivity, and specificity to detect IT in AD was 64% (95% confidence interval [CI] 56-72%), 69% (95%CI 60-78%), and 25% (95%CI 3.3-45%), respectively. In the diastolic phase (70%), the accuracy, sensitivity, and specificity to detect IT in AD was 52% (95%CI 43-60%), 52% (95%CI 42-61%), and 50% (95%CI 25-75%), respectively. The accuracy to detect IT in AD on ECG-gated CTA was significantly higher in the systolic phase than that in the diastolic phase (P = 0.025). However, there were no differences in the accuracy (83%; 95%CI 78-89%), sensitivity (71%; 95%CI 62-80%), or specificity (100%; 95%CI 100%) to detect ULP in IMH between the cardiac cycle phases. CONCLUSION: Although it is currently recommended for routine diagnosis of AD and IMH, single-diastolic-phase ECG-gated CTA has risk to miss some IT in AD that are detectable in the systolic phase on full-phase ECG-gated CTA. This information is critical for determining the optimal treatment strategy for AD.


Asunto(s)
Disección Aórtica , Angiografía por Tomografía Computarizada , Disección Aórtica/diagnóstico por imagen , Aorta Torácica , Electrocardiografía , Hematoma/terapia , Humanos , Estudios Retrospectivos , Úlcera
4.
Nature ; 456(7222): 617-9, 2008 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-19052622

RESUMEN

Type Ia supernovae are thermonuclear explosions of white dwarf stars in close binary systems. They play an important role as cosmological distance indicators and have led to the discovery of the accelerated expansion of the Universe. Among the most important unsolved questions about supernovae are how the explosion actually proceeds and whether accretion occurs from a companion or by the merging of two white dwarfs. Tycho Brahe's supernova of 1572 (SN 1572) is thought to be one of the best candidates for a type Ia supernova in the Milky Way. The proximity of the SN 1572 remnant has allowed detailed studies, such as the possible identification of the binary companion, and provides a unique opportunity to test theories of the explosion mechanism and the nature of the progenitor. The determination of the hitherto unknown spectroscopic type of this supernova is crucial in relating these results to the diverse population of type Ia supernovae. Here we report an optical spectrum of Tycho's supernova near maximum brightness, obtained from a scattered-light echo more than four centuries after the direct light from the explosion swept past the Earth. We find that SN 1572 belongs to the majority class of normal type Ia supernovae.

5.
Kyobu Geka ; 67(1): 79-82, 2014 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-24743416

RESUMEN

A 43-year-old female with a history of osteogenesis imperfecta was admitted to our hospital for congestive heart failure due to mitral valve regurgitation. The patient had suffered from bone fractures 5 times, dislocation of elbow and fingers 3 times since childhood, and subarachnoid hemorrhage 2 years before. She and her son have blue scleras. She was diagnosed with osteogenesis imperfecta type IA clinically. Echocardiography revealed severe mitral regurgitation and aneurysmal formation in the interatrial septum bulging to the right atrium. Mitral valve replacement and repair of the atrial septum were performed without any blood transfusion, but with rib fractures. Echocardiography showed no peri-valvular regurgitation at 1 year after the valve replacement. Cardiovascular disease is rarely associated with osteogenesis imperfecta, but its surgical mortality rate is high due to coagulation abnormality and fragile tissue. To reduce postoperative complications, precise classification of the disease and careful handling of the tissues during operation will be needed.


Asunto(s)
Aneurisma Cardíaco/complicaciones , Tabiques Cardíacos , Insuficiencia de la Válvula Mitral/complicaciones , Osteogénesis Imperfecta/complicaciones , Adulto , Femenino , Prótesis Valvulares Cardíacas , Humanos , Insuficiencia de la Válvula Mitral/cirugía
6.
PLoS One ; 19(2): e0298644, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38394249

RESUMEN

BACKGROUND: The most appropriate surgical method for patients with uncomplicated type B aortic dissection (UTBAD) in the chronic phase remains controversial. This study evaluated the outcomes of patients with UTBAD who needed aortic treatment as well as the impact of the treatment method or indication criteria on their prognosis. METHODS: This retrospective review of 106 consecutive patients with aortic events in the chronic phase who underwent initial treatment for UTBAD between 2004 and 2021 comprised three groups: 19 patients who underwent endovascular repair (TEVAR), 38 who underwent open aortic repair and the medication group that included 49 patients. Aortic events were defined as a late operation or indication for operation for dissected aorta, aortic diameter (AD) ≥ 55 mm, rapid aortic enlargement (≥5 mm/6 months), and saccular aneurysmal change. The endpoint was all-cause death. We assessed the association between treatment methods or surgical indication criteria and mortality using a Cox regression analysis. RESULTS: The 5-year actuarial mortality rates were 27.1% in the TEVAR group, 19.6% in the open aortic repair group, and 38.4% in the medication group (p = 0.86). Moreover, the 5-year actuarial mortality rates in patients who had AD ≥ 55 mm were significantly higher than those patients with other surgical indication criteria (41.2% vs. 18.7%, p < 0.01). Multivariable analysis revealed a significant difference in AD ≥ 55 mm (hazard ratio [HR]: 2.88, 95% confidence interval [CI] 1.38-6.02, p < 0.01) and age (HR: 1.09, 95% CI 1.05-1.13, p < 0.01). CONCLUSIONS: Under the existing surgical indication criteria, there was no difference in mortality rates among patients with UTBAD based on their surgical treatment.


Asunto(s)
Aneurisma de la Aorta Torácica , Disección Aórtica , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Humanos , Implantación de Prótesis Vascular/efectos adversos , Aneurisma de la Aorta Torácica/cirugía , Resultado del Tratamiento , Factores de Riesgo , Disección Aórtica/cirugía , Estudios Retrospectivos , Procedimientos Endovasculares/efectos adversos
7.
Ann Vasc Dis ; 16(3): 230-233, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37779654

RESUMEN

An 81-year-old Japanese man who had distal aortic arch dilatation at age 77 had thoracic endovascular aortic surgery. The patient developed a fever and was taken to the hospital. Reduced diffusion in the descending aortic wall along the stent graft was discovered using whole-body diffusion-weighted imaging with background body signal suppression, and stent-graft infection was identified. The 16S ribosomal RNA gene analysis and blood culture results identified Campylobacter insulaenigrae as the etiological bacterial species. The patient was released from the hospital after 6 weeks of antibiotic treatment since the swelling and inflammatory response had decreased.

8.
Nature ; 443(7108): 186-8, 2006 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-16971942

RESUMEN

When galaxy formation started in the history of the Universe remains unclear. Studies of the cosmic microwave background indicate that the Universe, after initial cooling (following the Big Bang), was reheated and reionized by hot stars in newborn galaxies at a redshift in the range 6 < z < 14 (ref. 1). Though several candidate galaxies at redshift z > 7 have been identified photometrically, galaxies with spectroscopically confirmed redshifts have been confined to z < 6.6 (refs 4-8). Here we report a spectroscopic redshift of z = 6.96 (corresponding to just 750 Myr after the Big Bang) for a galaxy whose spectrum clearly shows Lyman-alpha emission at 9,682 A, indicating active star formation at a rate of approximately 10M(o) yr(-1), where M(o) is the mass of the Sun. This demonstrates that galaxy formation was under way when the Universe was only approximately 6 per cent of its present age. The number density of galaxies at z approximately 7 seems to be only 18-36 per cent of the density at z = 6.6.

9.
Interact Cardiovasc Thorac Surg ; 34(6): 1132-1140, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35147677

RESUMEN

OBJECTIVES: In uncomplicated type B aortic dissection, a large false lumen (FL) is reportedly a risk factor for late aortic events. However, it is unclear how the relationship between the false and true lumen (TL) diameters affects the dissected aorta. This study aimed to evaluate the impact on clinical outcomes of the FL being larger than the TL. METHODS: We retrospectively reviewed 111 consecutive patients with uncomplicated acute type B aortic dissection between 2004 and 2018. We divided the patients into group A (FL > TL; n = 51) and group B (FL ≤ TL; n = 60), and compared the outcomes. The endpoints were aortic events, including surgery for aortic dissection and indication for surgery, and mortality. RESULTS: The 5-year incidence rates of aortic events were 68.4% in Group A and 33.6% in Group B (P = 0.002). The 5-year all-cause mortality rates were 5.3% in Group A and 21.9% in Group B (P = 0.003). The multivariable analyses revealed that FL > TL was an independent factor associated with aortic events (adjusted hazard ratio 2.482, 95% confidence interval 1.467-4.198, P < 0.001), but had low mortality (adjusted hazard ratio 0.209, 95% confidence interval 0.073-0.597, P = 0.003). CONCLUSIONS: Patients with uncomplicated type B aortic dissection with FL > TL at admission are at increased risk of aortic events but improve mortality compared to patients with FL ≤ TL. CLINICAL TRIAL REGISTRATION: UMIN000036997.


Asunto(s)
Aneurisma de la Aorta Torácica , Disección Aórtica , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Disección Aórtica/complicaciones , Disección Aórtica/diagnóstico por imagen , Disección Aórtica/cirugía , Aorta/cirugía , Aneurisma de la Aorta Torácica/complicaciones , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/efectos adversos , Procedimientos Endovasculares/efectos adversos , Humanos , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
10.
Kyobu Geka ; 63(3): 204-7, 2010 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-20214348

RESUMEN

A 63-year-old woman who underwent surgery for valve replacement had shocks 2 times. First, 1 postoperative day (POD), she had dyspnea, high grade fever and tacycardia. Then, she was intubated again, and needed intraaortic ballon pumping (IABP) support. Second, 32 POD, she had dyspnea, loss of consciousness and metabolic acidosis. Then she was intubated and needed continuous hemodiafiltration (CHDF). In both cases, causes were unknown, but she recovered from shocks after steroid therapy. Relative adrenal insufficiency during septic shock has been well known, and it was reported that steroid therapy reduce the risk of death. Also in cardiac surgery, relative adrenal insufficiency and euthyroid sick syndrome due to stress may occur. In a case of shock requiring large amount of catecholamine after cardiac surgery and the reason of the shock is unknown, specimens of adrenocorticotropic hormone (ACTH), cortisol, thyroid-stimulating hormone (TSH), free T3 and free T4 should be taken following by administration of 100 mg hydrocortisone intravenously.


Asunto(s)
Implantación de Prótesis de Válvulas Cardíacas , Hidrocortisona/uso terapéutico , Choque/tratamiento farmacológico , Hiperfunción de las Glándulas Suprarrenales/complicaciones , Femenino , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias , Choque/etiología
11.
Jpn J Radiol ; 38(11): 1036-1045, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32710132

RESUMEN

PURPOSE: To compare the accuracy of non-electrocardiogram (ECG)-gated CT angiography (CTA), single-diastolic-phase ECG-gated CTA, and full-phase ECG-gated CTA in detecting the intimal tear (IT) in aortic dissection (AD) and ulcer-like projection (ULP) in intramural hematoma (IMH). MATERIALS AND METHODS: A total of 81 consecutive patients with AD and IMH of the thoracic aorta were included in this single-center retrospective study. Non-ECG-gated CTA, single-diastolic-phase ECG-gated CTA, and full-phase ECG-gated CTA were used to detect the presence of the IT and ULP in thoracic aortic regions including the ascending aorta, aortic arch, and proximal and distal descending aorta. RESULTS: The accuracy of detecting the IT and ULP was significantly greater using full-phase ECG-gated CTA (88% [95% CI: 100%, 75%]) than non-ECG-gated CTA (72% [95% CI: 90%, 54%], P = 0.001) and single-diastolic-phase ECG-gated CTA (76% [95% CI: 93%, 60%], P = 0.008). CONCLUSION: Full-phase ECG-gated CTA is more accurate in detecting the IT in AD and ULP in IMH, than non-ECG-gated CTA and single-diastolic-phase ECG-gated CTA.


Asunto(s)
Aneurisma de la Aorta/diagnóstico por imagen , Disección Aórtica/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Hematoma/diagnóstico por imagen , Túnica Íntima/diagnóstico por imagen , Úlcera/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Disección Aórtica/complicaciones , Aorta/diagnóstico por imagen , Aneurisma de la Aorta/complicaciones , Estudios de Cohortes , Electrocardiografía/métodos , Femenino , Hematoma/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Úlcera/complicaciones
12.
Cancer Immunol Immunother ; 58(11): 1843-52, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19396597

RESUMEN

To investigate the safety and immunological responses of personalized peptide vaccination in combination with oral administration of UFT and UZEL for metastatic colorectal carcinoma (mCRC), fourteen patients were enrolled in the present study. Peptides were determined based on the presence of peptide-specific cytotoxic T lymphocyte precursors and IgG in each patient. A maximum of four peptides were subcutaneously administered weekly with UFT (300 mg/m2 day(-1)) and UZEL (75 mg/day) for 4 weeks, followed by 1 week of rest. This therapy was well-tolerated although there was a grade-3 skin reaction at the vaccination site in one patient. An increase in peptide-specific interferon-gamma production or peptide-specific IgG after the tenth vaccination was observed in nine of ten or eight of ten patients tested, respectively. IgG responses were well correlated with overall survival (P = 0.0215). The safety and immunological responsiveness of the present therapy suggest that this combination would be of clinical benefit for mCRC patients, and further trials are merited.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Vacunas contra el Cáncer/inmunología , Neoplasias Colorrectales/terapia , Antígenos HLA-A/inmunología , Antígeno HLA-A2/inmunología , Leucovorina/administración & dosificación , Vacunación , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/mortalidad , Terapia Combinada , Femenino , Antígeno HLA-A24 , Humanos , Interferón gamma/biosíntesis , Leucovorina/efectos adversos , Masculino , Persona de Mediana Edad , Linfocitos T Citotóxicos/inmunología , Tegafur/administración & dosificación , Tegafur/efectos adversos , Uracilo/administración & dosificación , Uracilo/efectos adversos
13.
EJVES Short Rep ; 38: 4-7, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29276787

RESUMEN

A 71 year old male who had undergone extra-anatomic bypass grafting between the ascending aorta and the thoraco-abdominal aorta at 41 years of age for aortic coarctation was admitted with back pain and dyspnea. A 16 mm Cooley double velour knitted polyethylene terephthalate (PET) graft was used in the initial operation in 1983. Computed tomography showed disruption of the initial PET graft perforating the right atrium, and a pseudoaneurysm at the distal anastomosis. The patient was in acute cardiac failure because of left to right shunting. A two stage operation was performed. The first stage comprised emergency re-grafting and right atrium repair, and the second stage re-grafting for the pseudoaneurysm. The patient is doing well 48 months post-operatively; however, monitoring of the patient will continue for potential PET graft rupture.

14.
Interact Cardiovasc Thorac Surg ; 26(2): 176-182, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29049807

RESUMEN

OBJECTIVES: Medical treatment is the gold standard for uncomplicated acute Type B aortic dissection (ATBAD). Although endovascular treatment could become an alternative therapy, it is unclear which ATBAD patients should undergo endovascular intervention. We aimed to evaluate the outcomes of patients with uncomplicated ATBAD and identify the risk factors for major adverse events. METHODS: We retrospectively reviewed 134 consecutive patients who underwent initial treatment for uncomplicated ATBAD between 2004 and 2015. Follow-up rate was 98.5%, and the median follow-up period was 47 months. We evaluated the incidence of major adverse events (aortic-related death, aortic surgery and dilated aorta ≥ 55 mm) and identified the predictors of major adverse events using multivariable analysis. RESULTS: In-hospital mortality rate was 0.7% (1/134). During follow-up, 46 patients had major adverse events. The 1-, 3-, and 5-year rates of freedom from major adverse events were 79.8%, 71.4%, and 63.6%, respectively. The independent risk factors for major adverse events were initial aortic diameter ≥40 mm (hazard ratio 3.735, 95% confidence interval 1.888-7.390; P < 0.001) and false-lumen diameter > true-lumen diameter (hazard ratio 3.411, 95% confidence interval 1.491-7.806; P = 0.004). CONCLUSIONS: Initial aortic diameter ≥40 mm and false-lumen diameter > true-lumen diameter are predictors of major adverse events after uncomplicated ATBAD. Patients with these risk factors may benefit from early endovascular intervention. Clinical registration number: UMIN 000025388, https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000029229.


Asunto(s)
Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/diagnóstico , Disección Aórtica/diagnóstico , Imagenología Tridimensional , Tomografía Computarizada por Rayos X/métodos , Anciano , Disección Aórtica/cirugía , Aneurisma de la Aorta Torácica/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores de Tiempo , Procedimientos Quirúrgicos Vasculares
15.
Hepatogastroenterology ; 54(74): 407-13, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17523285

RESUMEN

BACKGROUND/AIMS: We prospectively compared changes in function between colonic J-pouch and straight anastomoses from 1 to 5 years after low anterior resection for rectal cancer. METHODOLOGY: At 1, 3, and 5 years after surgery, functional outcome was compared between 48 patients with J-pouch reconstruction (J group) and 51 with straight anastomosis (S group), using a 17-item questionnaire (overall best, 0; overall worst, 26). Reservoir function was evaluated manovolumetrically. RESULTS: At 5 years, patients with ultralow anastomoses (< or =4 cm from anal verge) had fewer bowel movements during day or night, and less urgency and soiling in the J than S group. At that time, patients with low anastomoses (5 to 8 cm above the verge), had fewer bowel movements at night and less urgency in the J than S group. Manovolumetric results were better in the J than S group for both anastomotic levels. Functional scores improved significantly over time for both anastomotic levels, especially in the S group. Mean scores with ultralow anastomoses were J-group, 5.6 at 1 year vs. 5.3 at 3 years (P = 0.0304) vs. 3.7 at 5 years (P < 0.0001); and S group, 10.2 at 1 year vs. 9.6 at 3 years (P = 0.0063) vs. 7.3 at 5 years (P < 0.0001). Mean scores with low anastomoses were J group, 3.4 at 1 year vs. 3.1 at 3 years (P = 0.0052) vs. 2.1 at 5 years (P = 0.0003); and S group, 5.2 at 1 year vs. 3.8 at 3 years (P < 0.0001) vs. 2.7 at 5 years (P < 0.0001). Manovolumetric results improved overtime in both groups. CONCLUSIONS: Functional outcome improved in the J and especially the S group over 5 years. However, function was better in the J than S group at all time points.


Asunto(s)
Anastomosis Quirúrgica , Reservorios Cólicos , Complicaciones Posoperatorias/fisiopatología , Neoplasias del Recto/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Canal Anal/fisiopatología , Canal Anal/cirugía , Defecación/fisiología , Incontinencia Fecal/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Manometría , Persona de Mediana Edad , Estudios Prospectivos , Recto/fisiopatología , Recto/cirugía
16.
J Am Coll Cardiol ; 46(4): 707-13, 2005 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-16098440

RESUMEN

OBJECTIVES: The purpose of this study was to test the hypothesis that activated monocytes with soluble plasma tissue factor (pTF) activate factors VII and X to generate thrombin. BACKGROUND: Despite heparin, thrombin is progressively generated during cardiac surgery with cardiopulmonary bypass (CPB), produces intravascular fibrin and fibrinolysis, and causes serious thromboembolic and nonsurgical bleeding complications. Thrombin is primarily produced in the surgical wound, but mechanisms are unclear. METHODS: In 13 patients, interactions of mononuclear cells, platelets, pTF, and pTF fractions to activate factors VII and X were evaluated in pre-bypass, perfusate, and pericardial wound blood before and during CPB. RESULTS: Monocytes are activated in wound, but not in pre-bypass or perfusate plasma (monocyte chemotactic protein-1 = 29.5 +/- 2.1 pmoles/l vs. 2.8 +/- 1.2 pmoles/l and 3.3 +/-1.4 pmoles/l, respectively). Wound pTF is substantially elevated compared to other locations (3.64 +/- 0.45 pmoles/l vs. 0.71 +/- 0.65 pmoles/l and 1.31 +/- 1.4 pmoles/l). Supernatant wound pTF contains 81.7% of TF antigen; wound microparticle pTF contains 18.3%. Wound monocytes and all C5a-stimulated monocytes (but not activated platelets) completely convert factor VII to factor VIIa with wound pTF. Activated monocytes more efficiently activate factor X with wound supernatant TF/factor VII(VIIa) complex than with wound microparticle TF/factor VII(fVIIa). The correlation coefficient (r) between wound thrombin generation (F1.2) and wound pTF concentration is 0.944 (p = 0.0004). CONCLUSIONS: During cardiac surgery with CPB, wound monocytes plus wound pTF or wound microparticle-free supernatant pTF preferentially accelerate activation of factor VII and factor X. This system represents a novel mechanism for thrombin generation via the TF coagulation pathway.


Asunto(s)
Coagulación Sanguínea/fisiología , Puente Cardiopulmonar/efectos adversos , Factor VII/biosíntesis , Factor X/biosíntesis , Monocitos/fisiología , Plasma/química , Hemorragia Posoperatoria/fisiopatología , Trombina/biosíntesis , Tromboplastina/análisis , Anciano , Anciano de 80 o más Años , Factores de Coagulación Sanguínea/fisiología , Western Blotting , Factor VII/análisis , Factor X/análisis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuidados Posoperatorios , Cicatrización de Heridas
17.
Thromb Haemost ; 95(3): 462-8, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16525574

RESUMEN

Soluble plasma tissue factor (TF) circulates in picomolar concentrations in healthy individuals and increases in a wide spectrum of diseases. This study tests the hypothesis that both truncated TF (rsTF) or soluble plasmaTF (pTF) in low concentration combine with monocytes or platelets to convert factorVII (fVII) to fVIIa. Both rsTF (33 kDa) and pTF (47 kDa), obtained from pericardial wounds of patients having cardiac surgery using cardiopulmonary bypass (CPB), were studied in association with blood cells and TF-bearing microparticles. Tissue factor was measured by ELISA. RsTF binds to erythrocytes, platelets, mononuclear cells and polymorphoneutrophils. The rate of fVII conversion with rsTF (1-10(3) nM) is highest with mononuclear cells, less with platelets, minimal with polymorphoneutrophils and undetectable with erythrocytes. Either stimulated or unstimulated mononuclear cells or platelets in the presence of 3.5 pM rsTF or pTF convert fVII (10 pM) [corrected] to fVIIa, but the amounts of fVIIa produced differ. When leukocytes or platelets are absent, microparticles associated with 3.5 pM TF antigen derived from pericardial wound plasma do not activate fVII. Stimulated mononuclear cells convert nearly all available fVII (10 nM) to fVIIa with 3.5 nM pTF; unstimulated mononuclear cells convert small amounts of fVII with 1 pM rsTF. In all comparisons mononuclear cells more efficiently convert fVII to fVIIa than do platelets. This study shows that stimulated mononuclear cells provide the most efficient platform for activation of rsTF or pTF at low concentrations of TF antigen.


Asunto(s)
Factor VIIa/metabolismo , Monocitos/efectos de los fármacos , Tromboplastina/farmacología , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Cinética , Monocitos/metabolismo , Fragmentos de Péptidos/farmacología , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacología , Tromboplastina/química , Tromboplastina/genética
18.
Chem Phys Lipids ; 142(1-2): 43-57, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16620799

RESUMEN

The self-association of sodium taurodeoxycholate (NaTDC) and a zwitterionic derivative of cholic acid (CHAPS) in deuterium oxide was investigated by one- and two-dimensional nuclear magnetic resonance spectroscopy (NMR) spectroscopy. Analysis of the concentration dependence of the chemical shifts of several protons suggested that NaTDC and CHAPS form nonamers and heptamers, respectively, as well as dimer. The equilibrium constants of dimerization and the micellar aggregation numbers are close to the literature values. From the intensities of intermolecular cross-peaks in the nuclear Overhauser effect spectroscopy (NOESY) and rotating frame nuclear Overhauser effect spectroscopy (ROESY) spectra of NaTDC and CHAPS micellar solutions, partial structures of their micelles were estimated. The CHAPS micelle consists mainly of the back-to-back association, similarly to taurocholate (NaTC). However, the NaTDC micelle consists of the back-to-face association, because the face of NaTDC is rather hydrophobic. Furthermore, the back of bile molecules forms a convex plane and the face forms a concave plane. The back-to-face structure of NaTDC will be stabilized by a close contact between these planes. The chemical shift changes of several protons of CHAPS and NaTC in the micellar state are close to each other, but are different from those of NaTDC. This finding is consistent with the difference in their micellar structures.


Asunto(s)
Ácidos y Sales Biliares/química , Detergentes/química , Espectroscopía de Resonancia Magnética/métodos , Ácidos y Sales Biliares/metabolismo , Ácidos Cólicos/química , Óxido de Deuterio/química , Difusión , Interacciones Hidrofóbicas e Hidrofílicas , Micelas , Modelos Moleculares , Protones , Ácido Taurodesoxicólico/química
19.
Gan To Kagaku Ryoho ; 33(12): 1745-7, 2006 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-17212094

RESUMEN

We herein administered combination-therapy using a personalized vaccination and the oral administration of UFT/UZEL for the treatment of either advanced or recurrent colorectal cancer. Safety and the efficacy of this new treatment modality were evaluated. Eight patients were enrolled in this clinical trial from July 2005 to May 2006. Up to 4 kinds of peptide vaccines which were selected according to the immune response of each patient were injected hypodermically every week. At the same time, UFT (300 mg/m2/day) and UZEL (75 mg/day) were also administered orally for 28 days followed by a 7-day rest period. Regarding the adverse events, callosity, a type of leukopenia, and liver-dysfunction, such as hyperbilirubinemia, an increase in the aminotransferase were observed. During the clinical evaluation after the end of the 2 courses, 3 cases showed progressive disease (PD) while 5 cases showed stable disease (SD). Our findings indicate that additional peptide vaccine therapy with UFT/UZEL, can be administered without compromising the patient's safety. Moreover, the use of UFT/UZEL does not normally interfere with the normal course of immune-therapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Vacunas contra el Cáncer/administración & dosificación , Neoplasias Colorrectales/terapia , Fluorouracilo/administración & dosificación , Leucovorina/administración & dosificación , Péptidos/inmunología , Administración Oral , Adulto , Anciano , Ensayos Clínicos Fase I como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/terapia
20.
Science ; 320(5880): 1195-7, 2008 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-18511684

RESUMEN

Cassiopeia A is the youngest supernova remnant known in the Milky Way and a unique laboratory for supernova physics. We present an optical spectrum of the Cassiopeia A supernova near maximum brightness, obtained from observations of a scattered light echo more than three centuries after the direct light of the explosion swept past Earth. The spectrum shows that Cassiopeia A was a type IIb supernova and originated from the collapse of the helium core of a red supergiant that had lost most of its hydrogen envelope before exploding. Our finding concludes a long-standing debate on the Cassiopeia A progenitor and provides new insight into supernova physics by linking the properties of the explosion to the wealth of knowledge about its remnant.

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