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1.
J Transl Med ; 12: 63, 2014 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-24612787

RESUMEN

BACKGROUND: To evaluate the safety of combination vaccine treatment of multiple peptides, phase I clinical trial was conducted for patients with advanced colorectal cancer using five novel HLA-A*2402-restricted peptides, three peptides derived from oncoantigens, ring finger protein 43 (RNF43), 34 kDa-translocase of the outer mitochondrial membrane (TOMM34), and insulin-like growth factor-II mRNA binding protein 3 (KOC1), and the remaining two from angiogenesis factors, vascular endothelial growth factor receptor 1 (VEGFR1) and VEGFR2. METHODS: Eighteen HLA- A*2402-positive colorectal cancer patients who had failed to standard therapy were enrolled in this study. 0.5 mg, 1.0 mg or 3.0 mg each of the peptides was mixed with incomplete Freund's adjuvant and then subcutaneously injected at five separated sites once a week. We also examined possible effect of a single site injection of "the cocktail of 5 peptides" on the immunological responses. ELISPOT assay was performed before and after vaccinations in the schedule of every 4 weeks. RESULTS: The vaccine treatment using multiple peptides was well tolerated without any severe treatment-associated systemic adverse events. Dose-dependent induction of peptide-specific cytotoxic T lymphocytes was observed. The single injection of "peptides cocktail" did not diminish the immunological responses. Regarding the clinical outcome, one patient achieved complete response and 6 patients revealed stable disease for 4 to 7 months. The median overall survival time (MST) was 13.5 months. Patients, in which we detected induction of cytotoxic T lymphocytes specific to 3 or more peptides, revealed significantly better prognosis (MST; 27.8 months) than those with poorer immune responses (MST; 3.7 months) (p = 0.032). CONCLUSION: Our cancer vaccine treatment using multiple peptides is a promising approach for advanced colorectal cancer with the minimum risk of systemic adverse reactions. CLINICAL TRIAL REGISTRATION: UMIN-CTR number UMIN000004948.


Asunto(s)
Vacunas contra el Cáncer/efectos adversos , Vacunas contra el Cáncer/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/inmunología , Epítopos/inmunología , Vacunas Combinadas/efectos adversos , Vacunas de Subunidad/efectos adversos , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Neoplasias Colorrectales/patología , Relación Dosis-Respuesta Inmunológica , Femenino , Humanos , Interferón gamma/metabolismo , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Monitorización Inmunológica , Análisis Multivariante , Metástasis de la Neoplasia , Modelos de Riesgos Proporcionales , Resultado del Tratamiento , Vacunación , Vacunas Combinadas/uso terapéutico , Vacunas de Subunidad/uso terapéutico
2.
J Transl Med ; 12: 108, 2014 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-24884643

RESUMEN

BACKGROUND: We previously conducted a phase I trial for advanced colorectal cancer (CRC) using five HLA-A*2402-restricted peptides, three derived from oncoantigens and two from vascular endothelial growth factor (VEGF) receptors, and confirmed safety and immunological responses. To evaluate clinical benefits of cancer vaccination treatment, we conducted a phase II trial using the same peptides in combination with oxaliplatin-based chemotherapy as a first-line therapy. METHODS: The primary objective of the study was the response rates (RR). Progression free survival (PFS), overall survival (OS), and immunological parameters were evaluated as secondary objective. The planned sample size was more than 40 patients for both HLA2402-matched and -unmatched groups. All patients received a cocktail of five peptides (3 mg each) mixed with 1.5 ml of IFA which was subcutaneously administered weekly for the first 12 weeks followed by biweekly administration. Presence or absence of the HLA-A*2402 genotype were used for classification of patients into two groups. RESULTS: Between February 2009 and November 2012, ninety-six chemotherapy naïve CRC patients were enrolled under the masking of their HLA-A status. Ninety-three patients received mFOLFOX6 and three received XELOX. Bevacizumab was added in five patients. RR was 62.0% and 60.9% in the HLA-A*2402-matched and -unmatched groups, respectively (p=0.910). The median OS was 20.7 months in the HLA-A*2402-matched group and 24.0 months in the unmatched group (log-rank, p=0.489). In subgroup with a neutrophil/lymphocyte ratio (NLR) of <3.0, patients in the HLA-matched group did not survive significantly longer than those in the unmatched group (log-rank, p=0.289) but showed a delayed response. CONCLUSIONS: Although no significance was observed for planned statistical efficacy endpoints, a delayed response was observed in subgroup with a NLR of <3.0. Biomarkers such as NLR might be useful for selecting patients with a better treatment outcome by the vaccination. TRIAL REGISTRATION: Trial registration: UMIN000001791.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/patología , Femenino , Antígenos HLA/análisis , Humanos , Masculino , Persona de Mediana Edad , Compuestos Organoplatinos/administración & dosificación , Oxaliplatino , Péptidos/administración & dosificación , Análisis de Supervivencia
3.
Nat Med ; 12(1): 133-7, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16327800

RESUMEN

The structure and function of blood vessels adapt to environmental changes such as physical development and exercise. This phenomenon is based on the ability of the endothelial cells to sense and respond to blood flow; however, the underlying mechanisms remain unclear. Here we show that the ATP-gated P2X4 ion channel, expressed on endothelial cells and encoded by P2rx4 in mice, has a key role in the response of endothelial cells to changes in blood flow. P2rx4(-/-) mice do not have normal endothelial cell responses to flow, such as influx of Ca(2+) and subsequent production of the potent vasodilator nitric oxide (NO). Additionally, vessel dilation induced by acute increases in blood flow is markedly suppressed in P2rx4(-/-) mice. Furthermore, P2rx4(-/-) mice have higher blood pressure and excrete smaller amounts of NO products in their urine than do wild-type mice. Moreover, no adaptive vascular remodeling, that is, a decrease in vessel size in response to a chronic decrease in blood flow, was observed in P2rx4(-/-) mice. Thus, endothelial P2X4 channels are crucial to flow-sensitive mechanisms that regulate blood pressure and vascular remodeling.


Asunto(s)
Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Receptores Purinérgicos P2/genética , Receptores Purinérgicos P2/metabolismo , Acetilcolina/metabolismo , Animales , Presión Sanguínea , Vasos Sanguíneos/patología , Northern Blotting , Calcio/metabolismo , Arterias Carótidas/patología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Técnicas de Transferencia de Gen , Proteínas Fluorescentes Verdes/metabolismo , Inmunohistoquímica , Arterias Mesentéricas/patología , Ratones , Ratones Transgénicos , Microscopía Fluorescente , Modelos Biológicos , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico/metabolismo , Reacción en Cadena de la Polimerasa , Receptores Purinérgicos P2X4 , Flujo Sanguíneo Regional , Factores de Tiempo
4.
J Theor Biol ; 287: 64-73, 2011 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-21820445

RESUMEN

The fractal state of the arterial vascular tree is considered to have a universal dimension related to the principle of minimum work rate, but can demonstrate the capacity to adapt to other dimensions in disease states such as congenital high-flow pulmonary hypertension (PH) by a process that is incompletely understood. To document and interpret fractal adaptation in patients with different degrees of PH, pulmonary and systemic vascular resistance was analyzed by a model that evaluated the fractal dimension, x, of the Poiseuille resistance contribution of the arterial vessel radius between 10 and 100µm, via the proportionality Q∝(R(peri)/BL)(-x/4), with Q, R(peri), and BL clinically observed variables representing total pulmonary or systemic blood flow, its peripheral arterial resistance, and body length, respectively. Identification of x in the pulmonary (P) and systemic (S) beds was evaluated from hemodynamic data of 213 patients, categorized into 7 groups by PH grade. In controls without PH, x(P)=2.2 while the dimension increased to 3.0, with the systemic dimension constant at x(S)=3.1. Our model predicts that severe grades of PH are associated with: a more elongated and hindered vessel in the periphery, and reductions in vessel numbers, as unit pulmonary resistive arterial trees (N(1)) and their component intra-acinar arteries (N(W)). These model network changes suggest a complex adaptive process of arterial network reorganization in the pulmonary circulation to minimize the work rate of high-flow congenital heart defects.


Asunto(s)
Cardiopatías Congénitas/fisiopatología , Modelos Cardiovasculares , Circulación Pulmonar/fisiología , Resistencia Vascular/fisiología , Adolescente , Adulto , Cateterismo Cardíaco , Niño , Preescolar , Femenino , Fractales , Cardiopatías Congénitas/complicaciones , Humanos , Hipertensión Pulmonar/etiología , Hipertensión Pulmonar/fisiopatología , Lactante , Masculino , Adulto Joven
5.
Med Biol Eng Comput ; 59(7-8): 1585-1596, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34264482

RESUMEN

Noninvasive and convenient measurement of vascular stiffness is of considerable importance for early detection and treatment of arteriosclerosis. Volume elastic modulus ([Formula: see text]) is one of representative measures reflecting effective vascular elasticity that is strongly dependent upon blood pressure (BP) or transmural pressure ([Formula: see text] = mean BP - (externally applied pressure)). However, its nonlinear nature in terms of functional form has not been fully investigated in human vasculature. This paper therefore seeks to clarify the functional form of [Formula: see text] in the human finger and radial arteries based on photoplethysmographic volume-oscillometry developed for novel indirect BP measurement. Using a smartphone-based instrument specially designed for this study, [Formula: see text] values at various [Formula: see text] levels were obtained in 11 male and female volunteers with various ages. It was demonstrated that [Formula: see text] showed an exponential behavior with respect to [Formula: see text] changes, expressed as [Formula: see text] ([Formula: see text], α; constant) with a high coefficient of determination, the validity of which was also supported through theoretical derivation. Conclusively, the [Formula: see text] is found to increase exponentially with arterial distending pressure, and the independent measures [Formula: see text] and α would be useful parameters to conveniently evaluate progressive changes of vascular stiffness among and/or within individuals, indicating that this measurement has potential for arteriosclerosis screening (200/200). Schematic diagram of overall configuration of the measurement system of arterial elasticity in the finger and the wrist, consisting of a measuring, signal processing and control (MSC) unit (surrounded by the dashed line) and a smartphone for data display and storage. An occlusive cuff and a photoplethysmographic placement of LED and PD for the finger and the wrist are shown in the upper middle part. Measurement scenes of the finger and the wrist are also inset in the upper left and in the upper right part, respectively.


Asunto(s)
Arteriosclerosis , Arteria Radial , Módulo de Elasticidad , Femenino , Dedos , Humanos , Masculino , Oscilometría
6.
Jpn J Infect Dis ; 73(5): 363-365, 2020 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-32350221

RESUMEN

In this study, we investigated four clinical cases of microbial contamination of in-use intravenous infusion fluid, detected by measuring "Adenosine triphosphate (ATP) + adenosine monophosphate (AMP)" ("ATP+AMP") levels. High "ATP+AMP" values correlate with microbial contamination, and by utilizing these values as indicator for microbial contamination possibility, we were able to rapidly detect the contamination and recommend replacement of catheters and administration sets. In three out of four cases, changing the infusion fluid led to improvement in the condition of the patients. "ATP+AMP" levels can be used to confirm microbial contamination of in-use intravenous infusion fluids, as it is fast (several minites) and convenient to measure them.


Asunto(s)
Adenosina Trifosfato/análisis , Infecciones Bacterianas/prevención & control , Contaminación de Medicamentos , Infusiones Intravenosas/métodos , Micosis/prevención & control , Nucleotidasas/análisis , Bacillus cereus/metabolismo , Candida tropicalis/metabolismo , Candidiasis/prevención & control , Fluidoterapia/métodos , Humanos , Infecciones por Serratia/prevención & control , Serratia marcescens/metabolismo
7.
BMC Infect Dis ; 9: 123, 2009 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-19664245

RESUMEN

BACKGROUND: There are limited choice of antimicrobial agents to treat infection with metallo-beta-lactamase-producing Pseudomonas aeruginosa. We evaluate the antimicrobial effects of aztreonam alone, colistin alone and the 3-drug combination of aztreonam, ceftazidime and amikacin on 23 strains of metallo-beta-lactamase-producing P. aeruginosa by time-killing tests. METHODS: Strains used were from different hospitals in Japan and had different pulse-field gel electrophoresis patterns by restriction with SpeI. The minimum inhibitory concentrations of 11 antimicrobial agents (piperacillin, piperacillin/tazobactam, imipenem, meropenem, aztreonam, ceftazidime, amikacin, tobramycin, arbekacin, ciprofloxacin and colistin) were determined using the agar dilution test. The effects of aztreonam, colistin and the combination of aztreonam, ceftazidime and amikacin were determined by time-killing studies. RESULTS: Bacteriostatic effects after 6 hours of drug exposure were observed in 12 strains (52.2%) of 23 strains of metallo-beta-lactamase-producing P. aeruginosa with 48 mg/l aztreonam, in 19 strains (82.6%) with the 3-drug combination of 16 mg/l aztreonam, 16 mg/l ceftazidime, and 4 mg/l amikacin, and in 23 strains (100%) with 2 mg/l colistin. Bactericidal effects after 6 h drug exposure were observed in 1 strain (4.3%) with 48 mg/l aztreonam, in 8 strains (30.4%) with the 3-drug combination and in all 23 strains (100%) with 2 mg/l colistin. CONCLUSION: Evaluation of in vitro antimicrobial effects on metallo-beta-lactamase-producing P. aeruginosa revealed relatively good effects of the 3-drug combination of aztreonam, ceftazidime and amikacin and marked effects of colistin.


Asunto(s)
Amicacina/farmacología , Antibacterianos/farmacología , Aztreonam/farmacología , Ceftazidima/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Colistina/farmacología , Farmacorresistencia Bacteriana , Quimioterapia Combinada , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa/enzimología , beta-Lactamasas/metabolismo
8.
J Biomech ; 88: 155-163, 2019 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-31023485

RESUMEN

To evaluate the efficiency of oxygen (O2) uptake from water through the fish gill lamellar system, a cost function (CF) representing mechanical power expenditure for water ventilation and blood circulation through the gill was formulated, by applying steady-state fluid mechanics to a homogeneous lamellar-channel model. This approach allowed us to express CF as the function of inter-lamellar water channel width (w) and to derive an analytical solution of the width (wmin) at the minimum CF. Morphometric and physiological data for rainbow trout in the literature were referred to calculate CF(w) curves and their wmin values at five intensity stages of swimming exercise. Obtained wmin values were evenly distributed around the standard measure of the width (ws = 24 µm) in this fish. Individual levels of CF(wmin) were also fairly close to the corresponding CF(ws) values within a 10% deviation, suggesting the reliability of approximating [CF(wmin) = CF(ws)]. The cost-performance of O2 uptake through the gill (ηg) was then assessed from reported data of total O2 uptake/CF(ws) at each intensity stage. The ηg levels at any swimming stage exceeded 95% of the theoretical maximum value, implying that O2 uptake is nearly optimally performed in the lamellar-channel system at all swimming speeds. Further analyses of O2 transport in this fresh water fish revealed that the water ventilation by the buccal/opercular pumping evokes a critical limit of swimming velocity, due to confined O2 supply to the peripheral skeletal muscles, which is avoided in ram ventilators such as tuna.


Asunto(s)
Peces/fisiología , Branquias/fisiología , Oxígeno/metabolismo , Animales , Transporte Biológico , Modelos Biológicos , Consumo de Oxígeno , Reproducibilidad de los Resultados , Respiración , Natación/fisiología , Agua/metabolismo
9.
J Biotechnol ; 133(2): 239-44, 2008 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-17850909

RESUMEN

We developed a compliant tube-type flow-loading apparatus that allows simultaneous application of physiological levels of shear stress and cyclic stretch to cultured cells and examined gene responses to a combination of the two forces. Human umbilical vein endothelial cells were exposed to shear stress and/or cyclic stretch for 24h, and changes in the mRNA levels of endothelin-1 (ET-1), a potent vasoconstrictor, and endothelial nitric oxide synthase (eNOS), which catalyzes the production of a potent vasodilator, NO, were determined by reverse transcriptase/PCR. Cyclic stretch (10%, 1 Hz) alone increased ET-1 mRNA levels approximately 1.6-fold, but had no effect on eNOS mRNA levels. A shear stress of 7 dynes/cm(2) and 15 dynes/cm(2) alone decreased ET-1 mRNA levels to around 83% and 61%, respectively, of the basal level, but increased the eNOS mRNA level to around 2.2-fold and 3.2-fold, respectively. When cyclic stretch and shear stress were applied simultaneously, ET-1 mRNA levels did not change significantly, but the eNOS mRNA level increased to a level equivalent to the increase in response to shear stress alone. These results indicate that the response of endothelial genes to shear stress or cyclic stretch depends on whether the two forces are applied separately or together.


Asunto(s)
Células Endoteliales/metabolismo , Endotelina-1/genética , Regulación de la Expresión Génica , Óxido Nítrico Sintasa de Tipo III/genética , Células Cultivadas , Células Endoteliales/citología , Células Endoteliales/enzimología , Endotelina-1/metabolismo , Regulación Enzimológica de la Expresión Génica , Humanos , Óxido Nítrico Sintasa de Tipo III/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Siliconas , Estrés Mecánico
10.
Jpn J Infect Dis ; 71(4): 306-308, 2018 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-29709985

RESUMEN

A simulation experiment was conducted to examine hand contamination from wiping the buttocks after the use and non-use of an electric toilet seat with water spray. A model of the buttocks was smeared with artificial diarrheal feces containing Serratia marcescens, and wiped by the participants wearing disposable gloves with 4 sheets of toilet paper after the use and non-use of the water spray of an electric toilet seat. Subsequently, the presence of S. marcescens on the surface of the gloves was quantified. After using the water spray, the mean count±standard deviation of S. marcescens was 0.067±0.249 colony-forming units (cfu)/glove, and it was 4,275±6,069 cfu/glove when water spray was not used. The cfu of S. marcescens was significantly lower when the water spray was used (p<0.00001) prior to wiping the artificial diarrheal feces. This result supports the effectiveness of water spray to prevent defecation-related hand contamination.


Asunto(s)
Higiene de las Manos/métodos , Mano/microbiología , Serratia marcescens/aislamiento & purificación , Cuartos de Baño , Adulto , Anciano , Recuento de Colonia Microbiana , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Biológicos , Modelos Teóricos
11.
Ann Thorac Surg ; 105(1): e7-e9, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29233366

RESUMEN

We report pulmonary resections for lung cancers in 2 patients with partial anomalous pulmonary venous connection (PAPVC) identified preoperatively. In case 1, right upper lobectomy was performed as the definitive operation for both lung cancer and PAPVC in the same lobe. In case 2, because lung cancer and PAPVC existed in different lobes, cardiac catheterization was performed to evaluate the need for correction of the PAPVC. Then, left lower lobectomy was safely performed without correcting the PAPVC located in the left upper lobe. The treatment plan for patients with PAPVC who require pulmonary resection should be carefully considered.


Asunto(s)
Neoplasias Pulmonares/cirugía , Neumonectomía , Venas Pulmonares/anomalías , Malformaciones Vasculares/cirugía , Anciano , Humanos , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Venas Pulmonares/diagnóstico por imagen , Malformaciones Vasculares/complicaciones , Malformaciones Vasculares/diagnóstico por imagen
12.
J Appl Physiol (1985) ; 102(6): 2315-23, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17347385

RESUMEN

The branching systems in our body (vascular and bronchial trees) and those in the environment (plant trees and river systems) are characterized by a fractal nature: the self-similarity in the bifurcation pattern. They increase their branch density toward terminals according to a power function with the exponent called fractal dimension (D). From a stochastic model based-on this feature, we formulated the fractal-based integrals to calculate such morphological parameters as aggregated branch length, surface area, and content volume for any given range of radius (r). It was followed by the derivation of branch number and cross-sectional area, by virtue of the logarithmic sectioning of the r axis and of the branch radius-length relation also given by a power function of r with an exponent (alpha). These derivatives allowed us to quantify various hydrodynamic parameters of vascular and bronchial trees as fluid conduit systems, including the individual branch flow rate, mean flow velocity, wall shear rate and stress, internal pressure, and circumferential tension. The validity of these expressions was verified by comparing the outcomes with actual data measured in vivo in the vascular beds. From additional analyses of the terminal branch number, we found a simple equation relating the exponent (m) of the empirical power law (Murray's so-called cube law) to the other exponents as (m=D+alpha). Finally, allometric studies of mammalian vascular trees revealed uniform and scale-independent distributions of terminal arterioles in organs, which afforded an infarct index, reflecting the severity of tissue damage following arterial infarction.


Asunto(s)
Vasos Sanguíneos/anatomía & histología , Vasos Sanguíneos/crecimiento & desarrollo , Bronquios/anatomía & histología , Bronquios/crecimiento & desarrollo , Fractales , Modelos Biológicos , Morfogénesis/fisiología , Animales , Simulación por Computador , Humanos , Modelos Anatómicos , Modelos Estadísticos , Procesos Estocásticos
13.
Jpn J Infect Dis ; 60(6): 367-9, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18032836

RESUMEN

In 106 inpatients with methicillin-resistant Staphylococcus aureus (MRSA)-positive body sites, MRSA contamination on their surrounding environmental surfaces and the palm of their dominant hand were detected and quantified. The association between MRSA-positive sites (palm of dominant hand, sputum, nasal discharge, pharyngeal mucosa, open pus, closed pus, urine, feces, and others) in patients and MRSA contamination in their surrounding environmental surfaces was evaluated by quantification theory II of multivariate analysis. The surrounding environmental surfaces were contaminated with MRSA in 54 (50.9%) of the 106 patients. The contamination of MRSA was 380.2 +/- 2,198.0 colony forming units (cfu)/100 cm(2) in 41 (40.2%) of 102 bed linen samples, 15.2 +/- 69.5 cfu/100 cm(2) in 19 (22.4%) of 85 overbed table samples, 12.8 +/- 56.5 cfu/about 100 cm(2) in 18 (20.9%) of 86 bed side rail samples, and 0.2 +/- 1.3 cfu/entire handle surface in 2 (2.7%) of 74 samples of room door handles on the inner side of the patients' room doors. In the palm, 6,743.3 +/- 65,446.5 cfu/palm MRSA was detected in 29 (29.6%) of 98 patients. MRSA in patients' palms had the most marked influence on MRSA contamination of their surrounding environmental surfaces. When MRSA is detected in patients' palms the possibility of MRSA contamination of their surrounding environmental surfaces is high.


Asunto(s)
Reservorios de Enfermedades , Contaminación de Equipos , Equipos y Suministros de Hospitales/microbiología , Resistencia a la Meticilina , Meticilina/farmacología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad , Habitaciones de Pacientes , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/efectos de los fármacos
14.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 63(1): 91-6, 2007 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-17344638

RESUMEN

Echo planar imaging (EPI) is highly sensitive to static magnetic field inhomogeneities. The degree of local image compression and stretching is a function of the static field gradient in the phase-encoding direction. This is caused by the accumulation of a phase shift. Any static field shift will lead to a position shift in the image, and it is the regions with large static fields that are the most difficult to correct. We reduce image distortion by SENSE with an array coil. However, we often use a surface coil because we cannot use an array coil in clinical studies. In this case, image distortion becomes greater, and reduction of distortion is very important. For the purpose of this study, we examined the relation between imaging parameters and image distortion. Image distortion of EPI is unrelated to the following parameters: number of phase encodings, half scan, echo time, and diffusion b-value. However, the following parameters influenced image distortion: FOV, number of frequency encodings, rectangle FOV, and multi-shot imaging. Image distortion of EPI is decided by the area of the phase-encoding gradient and the interval of readout gradients. We hope that many institutions will find these data useful.


Asunto(s)
Imagen Eco-Planar/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Artefactos , Imagen Eco-Planar/instrumentación , Campos Electromagnéticos
15.
J Appl Physiol (1985) ; 100(6): 1793-8, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16497835

RESUMEN

The objective of this study was to evaluate whether the nitric oxide (NO) released from vascular endothelial cells would decrease vessel wall oxygen consumption by decreasing the energy expenditure of mechanical work by vascular smooth muscle. The oxygen consumption rate of arteriolar walls in rat cremaster muscle was determined in vivo during NO-dependent and -independent vasodilation on the basis of the intra- and perivascular oxygen tension (Po2) measured by phosphorescence quenching laser microscopy. NO-dependent vasodilation was induced by increased NO production due to increased blood flow, whereas NO-independent vasodilation was induced by topical administration of papaverine. The energy efficiency of vessel walls was evaluated by the variable ratio of circumferential wall stress (amount of mechanical work) to vessel wall oxygen consumption rate (energy cost) in the arteriole between normal and vasodilated conditions. NO-dependent and -independent dilation increased arteriolar diameters by 13 and 17%, respectively, relative to the values under normal condition. Vessel wall oxygen consumption decreased significantly during both NO-dependent and -independent vasodilation compared with that under normal condition. However, vessel wall oxygen consumption during NO-independent vasodilation was significantly lower than that during NO-dependent vasodilation. On the other hand, there was no significant difference between the energy efficiency of vessel walls during NO-dependent and -independent vasodilation, suggesting the decrease in vessel wall oxygen consumption produced by NO to be related to reduced mechanical work of vascular smooth muscle.


Asunto(s)
Arteriolas/fisiología , Endotelio Vascular/fisiología , Óxido Nítrico/fisiología , Consumo de Oxígeno/fisiología , Vasodilatación/fisiología , Animales , Arteriolas/anatomía & histología , Fenómenos Biomecánicos , Endotelio Vascular/anatomía & histología , Masculino , Músculo Esquelético/irrigación sanguínea , Músculo Esquelético/fisiología , Papaverina/farmacología , Ratas , Ratas Wistar , Vasodilatación/efectos de los fármacos , Vasodilatadores/farmacología
16.
Hypertens Res ; 28(4): 331-8, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16138563

RESUMEN

A number of major clinical trials have demonstrated the clinical benefits of lowering blood pressure and have indicated that a majority of patients with hypertension will require more than one drug to achieve optimal blood pressure control. However, there is little data showing which antihypertensive combination best protects patients from cardiovascular events and which best achieves the target blood pressure with the fewest adverse events. The Combination Therapy of Hypertension to Prevent Cardiovascular Events (COPE) trial is the first large-scale investigator-initiated multicenter study with a prospective, randomized, open, blinded endpoint evaluation (PROBE) design to directly compare cardiovascular mortality and morbidity, incidence of adverse drug reaction, and degree of blood pressure reduction in Japanese hypertensive patients for a combination of angiotensin receptor blockers, beta-blockers or thiazide diuretics in addition to a calcium antagonist, benidipine hydrochloride, with a response-dependent dose titration scheme. The COPE trial is being conducted with the cooperation of more than 100 centers and clinics in Japan and involves 3,000 patients, who will be followed for 3 years. Eligible patients are being enrolled from May 2003 until May 2006. Results from the COPE trial should provide new evidence for selecting optimal combination therapies for hypertensive patients.


Asunto(s)
Antihipertensivos/uso terapéutico , Enfermedades Cardiovasculares/prevención & control , Hipertensión/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Enfermedades Cardiovasculares/tratamiento farmacológico , Quimioterapia Combinada , Humanos , Hipertensión/mortalidad , Estudios Multicéntricos como Asunto/métodos
17.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 61(11): 1551-8, 2005 Nov 20.
Artículo en Japonés | MEDLINE | ID: mdl-16317416

RESUMEN

Diffusion weighted imaging (DWI) theoretically aims to detect random motion over small distances, such as Brownian motion. Therefore, breath-hold scanning has been considered the only way to acquire DWI in the body without artifacts from bulk motion. Recent reports suggest that non-breath-hold scanning is feasible. The purpose of this study was to evaluate the influence of respiratory motion on DWI using a moving phantom model. Our results showed that the difference in apparent diffusion coefficient (ADC) was less than 10% between a static phantom and a moving phantom. There was no relation between the speed and stroke of the moving phantom and the calculated ADC. The results indicate that stable motion such as calm respiration does not cause signal loss on DWI, in contrast to intra-voxel incoherent motion (IVIM). The images obtained using this method showed high resolution and signal-to-noise ratio (SNR), suitable for three-dimensional display of the lesion.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Movimiento (Física) , Fantasmas de Imagen
18.
Infect Control Hosp Epidemiol ; 23(2): 98-9, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11893155

RESUMEN

A survey of 145 Japanese hospitals revealed the use of 4 inappropriate aldehyde disinfection methods in 5.5% to 16.8%. Following education, there was discontinuation of 3 of these practices in 26 of 28 affected centers, but only 4 of 18 affected centers stopped the use of formaldehyde vapor cabinets. There is a need to inform hospitals about inappropriate disinfection methods that pose chemical risks to patients and staff.


Asunto(s)
Desinfectantes/efectos adversos , Formaldehído/efectos adversos , Glutaral/efectos adversos , Hospitales , Control de Infecciones/métodos , Humanos , Japón , Cuerpo Médico de Hospitales , Encuestas y Cuestionarios
19.
J Appl Physiol (1985) ; 95(5): 2081-8, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12857765

RESUMEN

Endothelial progenitor cells (EPCs), circulating in peripheral blood, migrate toward target tissue, differentiate, and contribute to the formation of new vessels. In this study, we report that shear stress generated by blood flow or tissue fluid flow can accelerate the proliferation, differentiation, and capillary-like tube formation of EPCs. When EPCs cultured from human peripheral blood were subjected to laminar shear stress, the cells elongated and oriented their long axes in the direction of flow. The cell density of the EPCs exposed to shear stress was higher, and a larger percentage of these cells were in the G2-M phase of the cell cycle, compared with EPCs cultured under static conditions. Shear stress markedly increased the EPC expression of two vascular endothelial growth factor receptors, kinase insert domain-containing receptor and fms-like tyrosine kinase-1, and an intercellular adhesion molecule, vascular endothelial-cadherin, at both the protein and mRNA levels. Assays for tube formation in the collagen gels showed that the shear-stressed EPCs formed tubelike structures and developed an extensive tubular network significantly faster than the static controls. These findings suggest that EPCs are sensitive to shear stress and that their vasculogenic activities may be modulated by shear stress.


Asunto(s)
Endotelio Vascular/citología , Endotelio Vascular/fisiología , Neovascularización Fisiológica/fisiología , Células Madre/citología , Células Madre/fisiología , Antígenos CD , Biomarcadores , Cadherinas/genética , Diferenciación Celular/fisiología , División Celular/fisiología , Colágeno , Proteínas de la Matriz Extracelular/genética , Geles , Humanos , Leucocitos Mononucleares/citología , ARN Mensajero/análisis , Estrés Mecánico , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética
20.
Dent Mater J ; 21(4): 306-13, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12608420

RESUMEN

The depths of calcium-ion incorporation into a commercially pure titanium and an experimental beta-type titanium alloy were determined using Auger electron spectroscopy. After the electrochemical deposition of apatite, new compositional gradients appeared in the profiles in which the Ca and P concentrations gradually decreased as a function of the depth up to 6-8 nm. The relative concentration of Ca in the outermost layer was higher than that of P. On the other hand, after the soaking in a simulated body fluid, the relative concentration of P was higher than that of Ca in the outermost layer. These results suggested that Ca ions were well incorporated into the outermost oxide layer of titanium accompanied by the electrochemical apatite-deposition on its surface.


Asunto(s)
Apatitas/química , Calcio/química , Titanio/química , Materiales Biocompatibles/química , Líquidos Corporales/química , Aleaciones Dentales/química , Electroquímica , Galvanoplastia , Humanos , Niobio/química , Fósforo/química , Análisis Espectral , Propiedades de Superficie
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