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1.
Allergy ; 72(4): 598-603, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27644013

RESUMEN

INTRODUCTION: Component-resolved diagnostics using specific IgE to 2 S albumins has shown to be a valuable new option in diagnostic procedure. Ana o 3 is a 2 S albumin from cashew. The aim of this study was to investigate the role of Ana o 3-specific serum IgE in the diagnosis of cashew allergy and to identify cut-off levels to replace oral food challenges. Moreover, the value of additional determination of total IgE has been investigated. METHODS: In a multicentre study, we analysed specific IgE to cashew extract and Ana o 3 as well as total IgE in children with suspected cashew allergy using the ImmunoCAP-FEIA and a standardized diagnostic procedure including oral challenges where indicated. RESULTS: A total of 61 patients were included in the study. Forty-two were allergic to cashew, and 19 were tolerant. In receiver operating curves, Ana o 3 discriminates between allergic and tolerant children better than cashew-specific IgE with an area under the curve of 0.94 vs 0.78. The ratio of Ana o 3-specific IgE to total IgE did not further improve the diagnostic procedure. Probability curves for Ana o 3-specific IgE have been calculated, and a 95% probability could be estimated at 2.0 kU/l. CONCLUSION: Specific IgE to Ana o 3 is a valuable tool for the diagnosis of cashew allergy. Considering its positive predictive value, it might allow to make a considerable number of oral challenges superfluous.


Asunto(s)
Alérgenos/inmunología , Anacardium/efectos adversos , Antígenos de Plantas/inmunología , Inmunoglobulina E/inmunología , Hipersensibilidad a la Nuez/diagnóstico , Hipersensibilidad a la Nuez/inmunología , Proteínas de Plantas/inmunología , Especificidad de Anticuerpos/inmunología , Niño , Femenino , Humanos , Inmunoglobulina E/sangre , Masculino , Pronóstico , Curva ROC
2.
Laryngorhinootologie ; 95(11): 774-782, 2016 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-27128640

RESUMEN

Objective: Voice feminization is an important step in the therapy of male-to-female transsexualism. Approaches are conservative voice therapy and surgical interventions. The most powerful parameter of gender perception is the fundamental frequency. Besides the vocal pitch, there are other parameters influencing gender perception of a voice, e. g. intonation, prosody or formant frequencies. Material and methods: In 21 male to female transgender persons after surgical elevation of the vocal pitch the Voice Handicap Index (VHI), the Life Satisfaction Questionnaire (FLZ) and a new addendum were used. A new algorithm for voice feminization in male-to-female transsexualism was deduced. Results: After elevation of the vocal pitch, the self-confidence of the male-to-female transgender persons has increased. Despite of an elevated pitch some persons were not satisfied with their voice. Conclusion: Surgical intervention changes only the pitch of a voice. To change other parameters, conservative voice therapy is necessary. If the transgender persons are able to reach a satisfying female voice with conservative voice therapy alone, surgical intervention is not indicated.


Asunto(s)
Algoritmos , Satisfacción del Paciente , Personas Transgénero , Calidad de la Voz , Femenino , Humanos , Masculino , Transexualidad
3.
Lupus ; 22(13): 1349-52, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23989738

RESUMEN

Antibodies to phosphatidylserine/prothrombin (aPS/PT) complex were measured in 728 serum specimens from patients suspected of having antiphospholipid syndrome (APS), but without diagnostic elevations in the levels of antibodies to cardiolipin or Beta-2 Glycoprotein 1 (ß2-GP1). Of the 728 specimens, 41 had elevated levels of aPS/PT. Thrombotic events occurred in 11 of the 22 patients with accessible medical histories. Six of the patients with accessible medical records also had laboratory evidence of the lupus anticoagulant. The identification of aPS/PT in patients without evidence of antibodies to cardiolipin, ß2-GP1, or the lupus anticoagulant can contribute to the identification of APS in patients that may go undetected with current testing methods.


Asunto(s)
Anticuerpos Antifosfolípidos/sangre , Síndrome Antifosfolípido/inmunología , Fosfatidilserinas/inmunología , Protrombina/inmunología , beta 2 Glicoproteína I/inmunología , Anticuerpos Anticardiolipina/sangre , Síndrome Antifosfolípido/sangre , Síndrome Antifosfolípido/complicaciones , Síndrome Antifosfolípido/diagnóstico , Biomarcadores/sangre , Ensayo de Inmunoadsorción Enzimática , Humanos , Inhibidor de Coagulación del Lupus/sangre , Valor Predictivo de las Pruebas , Trombosis/sangre , Trombosis/inmunología
4.
J Microsc ; 245(2): 161-70, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21999192

RESUMEN

Accurate extraction of cell outlines from microscopy images is essential for analysing the dynamics of migrating cells. Phase-contrast microscopy is one of the most common and convenient imaging modalities for observing cell motility because it does not require exogenous labelling and uses only moderate light levels with generally negligible phototoxicity effects. Automatic extraction and tracking of high-resolution cell outlines from phase-contrast images, however, is difficult due to complex and non-uniform edge intensity. We present a novel image-processing method based on refined level-set segmentation for accurate extraction of cell outlines from high-resolution phase-contrast images. The algorithm is validated on synthetic images of defined noise levels and applied to real image sequences of polarizing and persistently migrating keratocyte cells. We demonstrate that the algorithm is able to reliably reveal fine features in the cell edge dynamics.


Asunto(s)
Movimiento Celular/fisiología , Forma de la Célula/fisiología , Epidermis/ultraestructura , Procesamiento de Imagen Asistido por Computador/métodos , Microscopía de Contraste de Fase/métodos , Algoritmos , Animales , Polaridad Celular , Células Epidérmicas , Peces/fisiología
5.
J Periodontal Res ; 47(4): 479-87, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22212171

RESUMEN

BACKGROUND AND OBJECTIVE: Angiogenesis plays a crucial role in early wound healing and tissue regeneration. Although enamel matrix derivative (EMD) has demonstrated the potential to stimulate periodontal regeneration, the biological effects of EMD on angiogenesis and underlying mechanisms have not been fully elucidated. The aim of the present study was to examine the angiogenic effects of EMD in vitro. MATERIAL AND METHODS: Human umbilical vein endothelial cells (HUVECs) were used to assess the effect of EMD on proliferation, survival, adhesion and migration. The effect of EMD on HUVEC angiogenesis was assessed by a three-dimensional sprouting assay. In order to understand the signalling mechanism of altered cell proliferation of HUVECs caused by EMD, the phosphorylation status of ERK1/2 and of the serine/threonine protein kinase Akt was analysed by western blot using phospho-specific antibodies. RESULTS: The proliferation of HUVECs was stimulated by 50 µg/mL EMD, whereas higher concentrations (≥100 µg/mL) resulted in an increased apoptotic rate. The mitogenic response to EMD was associated with the activation of ERK1/2. Enamel matrix derivative did not affect cell adhesion, but all concentrations of EMD tested (0.1-250 µg/mL) promoted migration of HUVECs. Furthermore, EMD induced capillary-like sprout formation from HUVEC spheroids in a dose-dependent manner. CONCLUSION: Our data indicate that EMD acts as a proangiogenic factor in vitro and, as such, might contribute to periodontal tissue regeneration by stimulation of vessel formation during wound healing.


Asunto(s)
Proteínas del Esmalte Dental/farmacología , Células Endoteliales/efectos de los fármacos , Neovascularización Fisiológica/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos , Apoptosis , Adhesión Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Activación Enzimática , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Fosforilación , Cultivo Primario de Células , Proteínas Proto-Oncogénicas c-akt/metabolismo , Esferoides Celulares/efectos de los fármacos , Venas Umbilicales/citología
6.
Science ; 166(3912): 1502-3, 1969 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-17742848

RESUMEN

The helium-4 solar wind flux during the Apollo 11 lunar surface excursion was (6.3 +/- 1.2) x 10(6) atoms per square centimeter per second. The solar wind direction and energy are essentially not perturbed by the moon. Evidence for a lunar solar wind albedo was found.

7.
Caries Res ; 43(4): 261-8, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19439947

RESUMEN

Although CO(2) laser irradiation can decrease enamel demineralisation, it has still not been clarified which laser wavelength and which irradiation conditions represent the optimum parameters for application as preventive treatment. The aim of the present explorative study was to find low-fluence CO(2) laser (lambda = 10.6 microm) parameters resulting in a maximum caries-preventive effect with the least thermal damage. Different laser parameters were systematically evaluated in 3 steps. In the first experiment, 5 fluences of 0.1, 0.3, 0.4, 0.5 and 0.6 J/cm(2), combined with high repetition rates and 10 micros pulse duration, were chosen for the experiments. In a second experiment, the influence of different pulse durations (5, 10, 20, 30 and 50 micros) on the demineralisation of dental enamel was assessed. Finally, 3 different irradiation times (2, 5 and 9 s) were tested in a third experiment. In total, 276 bovine enamel blocks were used for the experiments. An 8-day pH-cycling regime was performed after the laser treatment. Demineralisation was assessed by lesion depth measurements with a polarised light microscope, and morphological changes were assessed with a scanning electron microscope. Irradiation with 0.3 J/cm(2), 5 micros, 226 Hz for 9 s (2,036 overlapping pulses) increased caries resistance by up to 81% compared to the control and was even significantly better than fluoride application (25%, p < 0.0001). Scanning electron microscopy examination did not reveal any obvious damage caused by the laser irradiation.


Asunto(s)
Susceptibilidad a Caries Dentarias/efectos de la radiación , Caries Dental/prevención & control , Esmalte Dental/efectos de la radiación , Dureza/efectos de la radiación , Láseres de Gas/uso terapéutico , Animales , Bovinos , Estudios Transversales , Terapia por Láser/instrumentación , Terapia por Láser/métodos , Modelos Lineales , Estadísticas no Paramétricas , Desmineralización Dental/prevención & control , Desmineralización Dental/radioterapia
8.
Cell Calcium ; 41(1): 41-50, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16876243

RESUMEN

Stretch-elicited intracellular calcium ([Ca(2+)](i)) changes in individual smooth muscle cells in a ring of aorta were measured simultaneously with the force developed by the ring. A phasic increase in [Ca(2+)](i) was observed in 30% of the cells and a sustained one in 10%. Depletion of intracellular calcium store by thapsigargin and caffeine decreased phasic and increased sustained calcium responses. The inhibition of calcium entry either by stretching the aorta in a calcium-free medium or by the inhibition of stretch-activated, non-selective cationic channels by 5 microM GsMtx-4 toxin, decreased the proportion of sustained [Ca(2+)](i) responses but increased transient responses. In this condition, a third of the cells responded to stretch by a bursts of [Ca(2+)](i) spikes. The decrease of calcium influx triggered the generation of burst of calcium spikes after the application of stretch steps to the vascular wall. We conclude that progressive recruitment of smooth muscle cells is the mechanism underlying the force-generating part of the myogenic response. Two types of stretch-elicited calcium responses were observed during the recruitment of the smooth muscle cells. One was a phasic calcium discharge generated by the sarcoplasmic reticulum. The second was a tonic response produced by the activation of the stretch-sensitive cationic channels allowing extracellular Ca(2+) entry.


Asunto(s)
Aorta Torácica/metabolismo , Señalización del Calcio/fisiología , Actinas/metabolismo , Animales , Aorta Torácica/fisiología , Citoesqueleto/metabolismo , Elasticidad , Técnicas In Vitro , Masculino , Ratones , Ratones Endogámicos C57BL , Contracción Muscular , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiología , Miocitos del Músculo Liso/metabolismo , Estrés Mecánico
9.
Mol Biol Cell ; 15(9): 4310-20, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15240821

RESUMEN

Myofibroblasts of wound granulation tissue, in contrast to dermal fibroblasts, join stress fibers at sites of cadherin-type intercellular adherens junctions (AJs). However, the function of myofibroblast AJs, their molecular composition, and the mechanisms of their formation are largely unknown. We demonstrate that fibroblasts change cadherin expression from N-cadherin in early wounds to OB-cadherin in contractile wounds, populated with alpha-smooth muscle actin (alpha-SMA)-positive myofibroblasts. A similar shift occurs during myofibroblast differentiation in culture and seems to be responsible for the homotypic segregation of alpha-SMA-positive and -negative fibroblasts in suspension. AJs of plated myofibroblasts are reinforced by alpha-SMA-mediated contractile activity, resulting in high mechanical resistance as demonstrated by subjecting cell pairs to hydrodynamic forces in a flow chamber. A peptide that inhibits alpha-SMA-mediated contractile force causes the reorganization of large stripe-like AJs to belt-like contacts as shown for enhanced green fluorescent protein-alpha-catenin-transfected cells and is associated with a reduced mechanical resistance. Anti-OB-cadherin but not anti-N-cadherin peptides reduce the contraction of myofibroblast-populated collagen gels, suggesting that AJs are instrumental for myofibroblast contractile activity.


Asunto(s)
Uniones Adherentes/metabolismo , Fibroblastos/citología , Fibroblastos/metabolismo , Mioblastos/citología , Mioblastos/metabolismo , Actinas/metabolismo , Animales , Fenómenos Biomecánicos , Cadherinas/metabolismo , Diferenciación Celular , Células Cultivadas , Colágeno , Femenino , Geles , Modelos Biológicos , Ratas , Ratas Wistar , Piel/citología , Piel/lesiones , Piel/metabolismo , Cicatrización de Heridas/fisiología
10.
Sci Rep ; 6: 31271, 2016 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-27507785

RESUMEN

Vascular smooth muscle cells exhibit intercellular Ca(2+) waves in response to local mechanical or KCl stimulation. Recently, a new type of intercellular Ca(2+) wave was observed in vitro in a linear arrangement of smooth muscle cells. The intercellular wave was denominated ultrafast Ca(2+) wave and it was suggested to be the result of the interplay between membrane potential and Ca(2+) dynamics which depended on influx of extracellular Ca(2+), cell membrane depolarization and its intercel- lular propagation. In the present study we measured experimentally the conduction velocity of the membrane depolarization and performed simulations of the ultrafast Ca(2+) wave along coupled smooth muscle cells. Numerical results reproduced a wide spectrum of experimental observations, including Ca(2+) wave velocity, electrotonic membrane depolarization along the network, effects of inhibitors and independence of the Ca(2+) wave speed on the intracellular stores. The numerical data also provided new physiological insights suggesting ranges of crucial model parameters that may be altered experimentally and that could significantly affect wave kinetics allowing the modulation of the wave characteristics experimentally. Numerical and experimental results supported the hypothesis that the propagation of membrane depolarization acts as an intercellular messenger mediating intercellular ultrafast Ca(2+) waves in smooth muscle cells.


Asunto(s)
Señalización del Calcio , Calcio/metabolismo , Músculo Liso Vascular/citología , Miocitos del Músculo Liso/metabolismo , Animales , Aorta/metabolismo , Membrana Celular/metabolismo , Células Cultivadas , Simulación por Computador , Uniones Comunicantes , Cinética , Potenciales de la Membrana , Modelos Teóricos , Ratas , Factores de Tiempo
11.
Cell Calcium ; 37(1): 25-34, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15541461

RESUMEN

Cytosolic-free [Ca2+] was evaluated in freshly dissociated smooth muscle cells from mouse thoracic aorta by the ratio of Fura Red and Fluo 4 emitted fluorescence using confocal microscopy. The role of intercellular communication in forming and shaping ATP-elicited responses was demonstrated. Extracellular ATP (250 microM) elicited [Ca2+]i transient responses, sustained [Ca2+]i rise, periodic [Ca2+]i oscillations and aperiodic repetitive [Ca2+]i transients. Quantity of smooth muscle cells in the preparation responding to ATP with periodical [Ca2+]i oscillations depended on the density of isolated cells on the cover slip. ATP-elicited bursts of [Ca2+]i spikes in 66+/-7% of cells in dense and in 33+/-8.5% of cells in non-dense preparations. The number of cells responding to ATP with bursts of [Ca2+]i spikes decreased from 55+/-5% (n=84) to 14+/-3% (n=141) in dense preparations pretreated with carbenoxolone. Simultaneous measurement of [Ca2+]i and ion currents revealed a correlation between [Ca2+]i and current oscillations. ATP-elicited bursts of current spikes in 76% of cells regrouped in small clusters and in 9% of isolated cells. Clustered cells responding to ATP with current oscillations had higher membrane capacity than clustered cells with transient and sustained ATP-elicited responses. Lucifer Yellow (1% in 130 mM KCl) injected into one of clustered cells was transferred to the neighboring cell only when ATP-elicited oscillations. Fast application of carbenoxolone (100 microM) inhibited ATP (250 microM) elicited Ca2+-dependent current oscillations. Taken together these results suggest that the probability of ATP (250 microM) triggered cytosolic [Ca2+]i oscillations accompanied with K+ and Cl- current oscillations increased with the coupling of smooth muscle cells.


Asunto(s)
Adenosina Trifosfato/metabolismo , Señalización del Calcio/fisiología , Comunicación Celular/fisiología , Uniones Comunicantes/fisiología , Miocitos del Músculo Liso/fisiología , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Adenosina Trifosfato/farmacología , Animales , Antiulcerosos/farmacología , Aorta/citología , Aorta/efectos de los fármacos , Aorta/fisiología , Relojes Biológicos/efectos de los fármacos , Relojes Biológicos/fisiología , Calcio/metabolismo , Canales de Calcio/efectos de los fármacos , Canales de Calcio/fisiología , Señalización del Calcio/efectos de los fármacos , Carbenoxolona/farmacología , Recuento de Células , Células Cultivadas , Canales de Cloruro/efectos de los fármacos , Canales de Cloruro/fisiología , Uniones Comunicantes/efectos de los fármacos , Isoquinolinas , Masculino , Ratones , Ratones Endogámicos C57BL , Contracción Muscular/efectos de los fármacos , Contracción Muscular/fisiología , Miocitos del Músculo Liso/efectos de los fármacos , Técnicas de Placa-Clamp , Canales de Potasio/efectos de los fármacos , Canales de Potasio/fisiología
12.
J Mol Biol ; 237(3): 266-74, 1994 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-8145241

RESUMEN

The prr locus was originally described as coding a ribonuclease that is activated after phage T4 infection to cut within the anticodon of a specific tRNA, inactivating protein synthesis and thus blocking phage development. Wild-type T4 phage has two genes coding the enzymes polynucleotide kinase and RNA ligase, whose only function seems to be to repair the damage done by the anticodon nuclease. As the only apparent function of the prr ribonuclease is to combat phage infection, it can be considered as an RNA-based restriction enzyme. In non-infected cells, the prr enzyme is kept inactive in a complex with three other proteins which were predicted on the basis of DNA homologies to be the subunits of a type IC DNA restriction and modification system. Unlike other type IC systems so far characterized, prr is chromosomally rather than plasmid coded. However, sequences upstream from prr also have homology with sequences from the plasmid R124 and the prophage P1. We have now investigated the prr system and shown that it is indeed a bona fide type IC system which we call EcoprrI, and which is active both in vivo and in vitro. The system is fully functional even in the absence of the anticodon nuclease and seems to be a typical type I enzyme. EcoprrI recognizes the sequence CCA(N7)RTGC. One peculiarity is that, with low efficiency, EcoprrI will recognize and methylate variants of its recognition sequence such as CCT(N7)ATGC, which is methylated in one strand of the DNA only.


Asunto(s)
Metilasas de Modificación del ADN/genética , Escherichia coli/genética , Genes Bacterianos/genética , Ribonucleasas/genética , Metiltransferasa de ADN de Sitio Específico (Adenina Especifica)/genética , Secuencia de Aminoácidos , Bacteriófago lambda/crecimiento & desarrollo , Secuencia de Bases , Clonación Molecular , Cósmidos , Metilasas de Modificación del ADN/química , Metilasas de Modificación del ADN/aislamiento & purificación , Metilasas de Modificación del ADN/metabolismo , ADN Viral/metabolismo , Metilación , Datos de Secuencia Molecular , Mutagénesis Insercional , Mapeo Restrictivo , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Metiltransferasa de ADN de Sitio Específico (Adenina Especifica)/química , Metiltransferasa de ADN de Sitio Específico (Adenina Especifica)/aislamiento & purificación , Metiltransferasa de ADN de Sitio Específico (Adenina Especifica)/metabolismo
13.
Cell Calcium ; 30(4): 261-7, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11587550

RESUMEN

The regulation of cytosolic-free calcium concentration of smooth-muscle and endothelial cells was mainly studied on cultured cells where the cross talk between these two coupled cell types is lost. In the present study, the cytosolic-free calcium concentration in the endothelial and the smooth-muscle cells was examined in an intact arterial wall in vitro. Strips of the main branch of rat mesenteric artery were used. Cytosolic-free calcium concentration [Ca2+]i was estimated by determining the fluorescence ratio of the two calcium probes, Fluo-4 and Fura red. The emitted fluorescence of both probes was measured with a confocal microscope. We showed that potassium and phenylephrine, which increase the cytosolic -free calcium concentration of the smooth-muscle cells, also indirectly influence the calcium concentration in the endothelial cells. By simultaneously determining [Ca2+]i in the endothelial and the smooth-muscle cells of an arterial strip, we observed that when calcium increases in the endothelial cells in response to acetylcholine, it slightly decreases in the smooth-muscle cells. We conclude that the regulation of [Ca2+]i in the arterial endothelial cell, depends according to the stimuli either upon the endothelial cells themselves, or upon the coupled smooth-muscle cells.


Asunto(s)
Calcio/metabolismo , Endotelio Vascular/metabolismo , Músculo Liso/metabolismo , Acetilcolina/farmacología , Agonistas alfa-Adrenérgicos/farmacología , Compuestos de Anilina/análisis , Animales , Benzofuranos/análisis , Citosol/metabolismo , Endotelio Vascular/efectos de los fármacos , Colorantes Fluorescentes/análisis , Imidazoles/análisis , Técnicas In Vitro , Masculino , Arterias Mesentéricas , Músculo Liso/efectos de los fármacos , Fenilefrina/farmacología , Potasio/farmacología , Ratas , Ratas Sprague-Dawley , Vasodilatadores/farmacología , Xantenos/análisis
14.
Hypertension ; 18(4 Suppl): II77-83, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1680813

RESUMEN

A new high-precision ultrasonic device was developed to determine noninvasively arterial compliance as a function of blood pressure. Because of the nonlinear elastic properties of arterial walls, measurements of compliance can be appropriately compared only if obtained over a range of pressures. This apparatus was used to evaluate in a double-blind, parallel fashion the effect of three different antihypertensive drugs and of a placebo on radial artery compliance. Thirty-two normotensive volunteers were randomly allocated to an 8-day, once-a-day oral treatment with either a placebo, 100 mg atenolol, 20 mg nitrendipine, or 20 mg lisinopril. Blood pressure, heart rate, radial artery diameter, and arterial compliance were measured immediately before as well as 6 hours after dosing on the first and last days of the study. On the eighth day of administration, within 6 hours after dosing, lisinopril induced an acute increase in radial artery diameter, from 2.99 +/- 0.06 to 3.28 +/- 0.09 mm (mean +/- SEM, p less than 0.01). The compliance-pressure curve was shifted upward on day 1 (p less than 0.01) as well as on day 8 (p less than 0.05). None of the other drugs induced any significant modification of these parameters. Arterial compliance has a strong nonlinear dependency on intra-arterial pressure and therefore has to be defined as a function of pressure. Antihypertensive drugs acting by different mechanisms may have different effects on the mechanical properties of large arteries.


Asunto(s)
Antihipertensivos/farmacología , Arterias/fisiología , Presión Sanguínea/efectos de los fármacos , Antagonistas Adrenérgicos beta/farmacología , Adulto , Angiotensina II/sangre , Arterias/efectos de los fármacos , Adaptabilidad/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino
15.
J Natl Cancer Inst Monogr ; (18): 35-9, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8562220

RESUMEN

Hispanics are among the fastest growing minorities in the United States, after Asian-Americans and Pacific-Islanders. Hispanics, Latinos, Chicanos, Mexican-Americans, Puerto Ricans, Cuban-Americans, etc. are all designations used to describe this large, heterogeneous population with different cultural, ethnic, geographic, and social backgrounds. There is still no clear definition of the term "Hispanic." The data available regarding the incidence, morbidity, and mortality from cancer in Hispanics are scarce, scattered, outdated, and often incomplete. From the studies looking at the accessibility and availability of medical care for this population, few have examined in detail the variability within the entire Hispanic population. The aggregation of culturally distinct subgroups, which have resided in the United States for different periods of time, into a more inclusive Hispanic category assumes that all persons of Mexican, Cuban, and Puerto Rican extraction have similar needs and experience similar barriers in using health services. There is, however, no clear evidence for this assumption. On the contrary, there is evidence that each group has specific characteristics that make it different and independent from another, despite the fact that they also share some commonalities. Because of the lower overall prevalence of cancer in this population, potential protective factors need to be explored. Hispanics, however, appear to have a less favorable stage of disease at presentation and have overall lower death rates from cancer than non-Hispanic whites, but lower overall survival in certain cancers. Demographic and epidemiologic data collection need to be updated and improved.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Hispánicos o Latinos , Neoplasias/etnología , Actitud Frente a la Salud , Ensayos Clínicos como Asunto/métodos , Recolección de Datos/métodos , Femenino , Accesibilidad a los Servicios de Salud , Necesidades y Demandas de Servicios de Salud , Hispánicos o Latinos/clasificación , Hispánicos o Latinos/psicología , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Incidencia , Masculino , Neoplasias/epidemiología , Neoplasias/prevención & control , Neoplasias/psicología , Selección de Paciente , Factores de Riesgo , Estados Unidos/epidemiología
16.
Mayo Clin Proc ; 59(7): 477-83, 1984 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6539842

RESUMEN

We assessed the nutritional status at the time of hospital admission of 74 patients who were admitted for elective gynecologic or urologic operations. Nutritional assessment included measurement of serum albumin, thyroxine-binding prealbumin, retinol-binding protein, weight-change history, estimate of daily protein and total calorie intake, and a global estimate of nutritional risk. The sensitivity, specificity, false-positive rate, likelihood ratio, and positive predictive value of these nutrition-related variables were analyzed in patients who stayed in the hospital for longer than 10 days and in those patients with recognized complications. In the analysis of patients who remained in the hospital longer than 10 days, the finding of a low serum protein concentration or a low protein intake was most sensitive, and a low serum albumin concentration was the most specific. A receiver-operating-characteristic diagram that depicts the sensitivity and false-positive rates for the single variables and the combinations of variables is probably the most clinically useful summary of our study. Using the information in such a diagram, a clinician might choose variables that are more sensitive to identify hospitalized patients who should receive special nutritional attention in comparison with another clinician who might need fewer false-positive results for a prospective study of nutritional intervention.


Asunto(s)
Proteínas Sanguíneas/análisis , Tiempo de Internación , Fenómenos Fisiológicos de la Nutrición , Complicaciones Posoperatorias , Adulto , Anciano , Infecciones Bacterianas/etiología , Reacciones Falso Positivas , Femenino , Enfermedades de los Genitales Femeninos/cirugía , Humanos , Masculino , Persona de Mediana Edad , Prealbúmina/análisis , Proteínas de Unión al Retinol/análisis , Riesgo , Albúmina Sérica/análisis , Enfermedades Urológicas/cirugía
17.
IEEE Trans Med Imaging ; 21(6): 662-7, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12166863

RESUMEN

Results of development and testing of the new medical imaging system are described. The system uses a planar array consisting of 256 electrodes and enables obtaining images of the three-dimensional conductivity distribution in regions below the skin's surface up to several centimeters deep. The developed measuring system and image reconstruction algorithm can be used for breast tissue imaging and diagnostics, in particular for malignant tumor detection. Examples of tomographic images obtained in vivo during clinical tests are presented. The mammary gland, being an organ-target, alters at the background with such physiological events as menstrual cycle, pregnancy, lactation, and postmenopause. The objectives of this paper include estimation of the possibilities of electrical impedance mammography for investigation of mammary glands' state among women with different hormonal status. We found that electrical impedance mammograms from different groups had clear visual distinctions and statistically significant differences in mammary glands' conductivity. Our data on conductivity distribution in the mammary gland during different physiological periods will allow us to use it as normal values in the future, to continue this research on mammary glands with different pathology.


Asunto(s)
Mama/anatomía & histología , Mama/fisiología , Impedancia Eléctrica , Imagenología Tridimensional/instrumentación , Imagenología Tridimensional/métodos , Tomografía/métodos , Adolescente , Adulto , Anciano , Envejecimiento/fisiología , Diseño de Equipo , Femenino , Humanos , Aumento de la Imagen , Menopausia/fisiología , Persona de Mediana Edad , Posmenopausia/fisiología , Embarazo
18.
J Biomech ; 29(5): 635-42, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8707790

RESUMEN

The dynamics of arterial wall remodeling was studied on the basis of a phenomenological mathematical model. Sustained hypertension was simulated by a step increase in blood pressure. Remodeling rate equations were postulated for the evolution of the geometrical dimensions that characterize the zero stress state of the artery. The driving stimuli are the deviations of the extreme values of the circumferential stretch ratios and the average stress from their values at the normotensive state. Arterial wall was considered to be a thick-walled tube made of nonlinear elastic incompressible material. Results showed that thickness increases montonically with time whereas the opening angle exhibits a biphasic pattern. Geometric characteristics reach asymptotically a new homeostatic steady state, in which the stress and strain distribution is practically identical with the distribution under normotensive conditions. The model predictions are in good agreement with published experimental findings.


Asunto(s)
Arterias/fisiología , Presión Sanguínea , Hemorreología , Modelos Cardiovasculares , Algoritmos , Arterias/anatomía & histología , Elasticidad , Predicción , Homeostasis , Humanos , Hipertensión/patología , Hipertensión/fisiopatología , Matemática , Estrés Mecánico
19.
J Biomech ; 34(11): 1463-9, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11672721

RESUMEN

Chondrocytes depend upon solute transport within the avascular extracellular matrix of adult articular cartilage for many of their biological activities. Alterations to bioactive solute transport may, therefore, represent a mechanism by which cartilage compression is transduced into cellular metabolic responses. We investigated the effects of cartilage static compression on diffusivity and partitioning of a range of model solutes including dextrans of molecular weights 3 and 40 kDa, and tetramethylrhodamine (a 430 Da fluorophore). New fluorescence methods were developed for real-time visualization and measurement of transport within compressed cartilage explants. Experimental design allowed for multiple measurements on individual explants at different compression levels in order to minimize confounding influences of compositional variations. Results demonstrate that physiological levels of static compression may significantly decrease solute diffusivity and partitioning in cartilage. Effects of compression were most dramatic for the relatively high molecular weight solutes. For 40 kDa dextran, diffusivity decreased significantly (p<0.01) between 8% and 23% compression, while partitioning of 3 and 40 kDa dextran decreased significantly (p<0.01) between free-swelling conditions and 8% compression. Since diffusivity and partitioning can influence pericellular concentrations of bioactive solutes, these observations support a role for perturbations to solute transport in mediating the cartilage biological response to compression.


Asunto(s)
Cartílago Articular/fisiología , Líquido Sinovial/fisiología , Soporte de Peso/fisiología , Animales , Cartílago Articular/citología , Cartílago Articular/metabolismo , Bovinos , Condrocitos/metabolismo , Condrocitos/fisiología , Dextranos/farmacocinética , Difusión , Matriz Extracelular/metabolismo , Matriz Extracelular/fisiología , Femenino , Colorantes Fluorescentes , Técnicas In Vitro , Articulación de la Rodilla/citología , Articulación de la Rodilla/metabolismo , Articulación de la Rodilla/fisiología , Microscopía Fluorescente , Peso Molecular , Ósmosis , Rodaminas/farmacocinética , Líquido Sinovial/metabolismo
20.
J Biomech ; 26(2): 201-9, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8429061

RESUMEN

A new method for the separation of forward and backward running waves in elastic conduits, with possible extension to the arterial system, has been developed. The mathematical model is based on the one-dimensional flow equations which allow the treatment of non-periodic or transient pressure and flow pulses. The method is fully nonlinear, i.e. no linearizing assumptions are made. The method includes the effects of convective acceleration and pressure-dependent vessel compliance. A first approximation for the fluid friction at the wall is also included. The application of the method requires the knowledge of the elastic properties, the instantaneous pressure and flow, as well as the instantaneous spatial derivatives of pressure and flow. Analysis of simulated data shows good results and suggests that the proposed method, unlike previous quasi-nonlinear and frequency domain methods, can be applied to strongly nonlinear and/or nonperiodic flows. The method predicts that if a linear analysis is applied to a nonlinear system errors arise.


Asunto(s)
Arterias/fisiología , Modelos Cardiovasculares , Arterias/anatomía & histología , Velocidad del Flujo Sanguíneo , Presión Sanguínea , Elasticidad , Humanos , Flujo Sanguíneo Regional , Reología , Estrés Mecánico , Viscosidad
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