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A newly produced murine recombinant angiotensin (Ang)-converting enzyme 2 (ACE2) was characterized in vivo and in vitro. The effects of available ACE2 inhibitors (MLN-4760 and 2 conformational variants of DX600, linear and cyclic) were also examined. When murine ACE2 was given to mice for 4 weeks, a marked increase in serum ACE2 activity was sustainable. In acute studies, mouse ACE2 (1 mg/kg) obliterated hypertension induced by Ang II infusion by rapidly decreasing plasma Ang II. These effects were blocked by MLN-4760 but not by either form of DX600. In vitro, conversion from Ang II to Ang-(1-7) by mouse ACE2 was blocked by MLN-4760 (10(-6) m) but not by either form of DX600 (10(-5) m). Quantitative analysis of multiple Ang peptides in plasma ex vivo revealed formation of Ang-(1-9) from Ang I by human but not by mouse ACE2. Both human and mouse ACE2 led to the dissipation of Ang II with formation of Ang (1-7). By contrast, mouse ACE2-driven Ang-(1-7) formation from Ang II was blocked by MLN-4760 but not by either linear or cyclic DX600. In conclusion, sustained elevations in serum ACE2 activity can be accomplished with murine ACE2 administration, thereby providing a strategy for ACE2 amplification in chronic studies using rodent models of hypertension and cardiovascular disease. Human but not mouse ACE2 degrades Ang I to form Ang-(1-9). There are also species differences regarding rodent and human ACE2 inhibition by known inhibitors such that MLN-4760 inhibits both human and mouse ACE2, whereas DX600 only blocks human ACE2 activity.  相似文献   
995.
Impaired interatrial conduction or interatrial block is well documented but is not described as an individual electrocardiographic (ECG) pattern in most of ECG books, although the term atrial abnormalities to encompass both concepts, left atrial enlargement (LAE) and interatrial block, has been coined. In fact, LAE and interatrial block are often associated, similarly to what happens with ventricular enlargement and ventricular block. The interatrial blocks, that is, the presence of delay of conduction between the right and left atria, are the most frequent atrial blocks. These may be of first degree (P-wave duration >120 milliseconds), third degree (longer P wave with biphasic [±] morphology in inferior leads), and second degree when these patterns appear transiently in the same ECG recording (atrial aberrancy). There are evidences that these electrocardiographic P-wave patterns are due to a block because they may (a) appear transiently, (b) be without associated atrial enlargement, and (c) may be reproduced experimentally. The presence of interatrial blocks may be seen in the absence of atrial enlargement but often are present in case of LAE. The most important clinical implications of interatrial block are the following: (a) the first degree interatrial blocks are very common, and their relation with atrial fibrillation and an increased risk for global and cardiovascular mortality has been demonstrated; (b) the third degree interatrial blocks are less frequent but are strong markers of LAE and paroxysmal supraventricular tachyarrhythmias. Their presence has been considered a true arrhythmological syndrome.  相似文献   
996.
Commercially pure (c.p.) titanium grade IV with a bimodal microstructure is a promising material for biomedical implants. The influence of the processing parameters on the physical, microstructural, and mechanical properties was investigated. The bimodal microstructure was achieved from the blends of powder particles with different sizes, while the porous structure was obtained using the space-holder technique (50 vol.% of ammonium bicarbonate). Mechanically milled powders (10 and 20 h) were mixed in 50 wt.% or 75 wt.% with c.p. titanium. Four different mixtures of powders were precompacted via uniaxial cold pressing at 400 MPa. Then, the specimens were sintered at 750 °C via hot pressing in an argon gas atmosphere. The presence of a bimodal microstructure, comprised of small-grain regions separated by coarse-grain ones, was confirmed by optical and scanning electron microscopies. The samples with a bimodal microstructure exhibited an increase in the porosity compared with the commercially available pure Ti. In addition, the hardness was increased while the Young’s modulus was decreased in the specimens with 75 wt.% of the milled powders (20 h).  相似文献   
997.
The Multi-Attitude Suicide Tendency Scale (MAST) was designed to assess suicidal tendencies in youth. This 30-item scale has four types of attitudes: attraction to life, repulsion by life, attraction to death, and repulsion by death. Normative, factor structure, and psychometric data were investigated with American youth with a range of suicidal ideations and behaviors. The reported factor structure was replicated with American youths. In addition, all four factor scales showed good reliability estimates. Finally, the relationships among the MAST factors and measures of suicidal behavior and ideation, social desirability, and general psychopathology were examined.  相似文献   
998.
ObjetivosConocer la perspectiva de profesionales sobre aspectos y dimensiones que deberían formar parte indispensable de la Atención Centrada en la Persona (ACP).DiseñoTécnica Delphi.EmplazamientoAtención Primaria.ParticipantesSetenta y cuatro expertos médicos especialistas en medicina familiar y comunitaria (MF), tutores docentes, psicólogos y sociólogos distribuidos por todo el territorio nacional (enero-junio 2015).MétodosRespondieron a tres cuestionarios: primero sobre aspectos que debería tener en cuenta un MF para realizar ACP en todas sus dimensiones. En el segundo se preguntó sobre el grado de acuerdo con cada ítem y dimensión en que lo clasificaba. Las respuestas se priorizaron en un tercer cuestionario (escala Likert, rango de puntuación 1-10).ResultadosLa tasa de respuesta (TR) al primer cuestionario fue de 54,05%, obteniéndose 84 ítems, los más frecuentes Respeto y Atención Integral. El 2.° cuestionario con TR = 48,6%, obtuvo 52 ítems con acuerdo superior al 75%. La TR del tercer cuestionario fue de 52,7%, obteniendo 21 ítems con puntuación > 9. Los valores más altos correspondieron a aspectos esenciales de la ACP: respeto, atención integral, enfoque biopsicosocial, autonomía del paciente y participación en la toma de decisiones.ConclusionesSe identificaron nuevas dimensiones: Prevención y promoción de la salud, Gestión de Recursos y Competencia Clínica; añadidas a las previamente descritas: Perspectiva biopsicosocial, Médico como persona, Paciente como persona, Relación médico-paciente y Poder y Responsabilidad compartidas.El respeto, la atención integral, el enfoque biopsicosocial, la autonomía del paciente y su participación en la toma de decisiones, son los aspectos más valorados entre los seleccionados por los profesionales participantes.Palabras clave: Atención centrada en el paciente, Atención primaria de salud, Evaluación del resultado de la atención al paciente, Técnica Delphi, Médicos de familia, Atención centrada en la persona  相似文献   
999.
The aim of the present study was to describe the epidemiological and clinical characteristics of inflammatory bowel disease (IBD), including medical and surgical treatments, in several countries in Latin America and the Caribbean.IBD is recognized as a global health problem because its incidence and prevalence have increased significantly over the last few years.This multicenter retrospective cohort study included 4714 patients with IBD diagnosed from 9 countries in Latin America and the Caribbean: Colombia, Cuba, Dominican Republic, Ecuador, Mexico, Peru, Puerto Rico, Uruguay, and Venezuela.Crohn disease (CD) was more frequent in Puerto Rico (71.9%), the Dominican Republic (61.0%), and Peru (53.1%). Ulcerative colitis was more frequent in Colombia (78.6%), Venezuela (78.2%), Mexico (75.5%), Cuba (69.9%), Ecuador (64.1%), and Uruguay (60.9%). The following clinical characteristics were more frequent in the Caribbean: penetrating behavior in CD, steroid dependence, steroid resistance, intolerance to thiopurines, extraintestinal manifestations, surgeries, hospitalizations due to IBD, and family history of IBD. The factors associated with the use of biological therapy were pancolitis in ulcerative colitis, penetrating behavior in CD, steroid resistance and dependence, presence of extraintestinal manifestations, and the need for surgery.This study from Latin America and the Caribbean demonstrated the different epidemiological and clinical characteristics of IBD.  相似文献   
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