LeNRT1.1 Improves Nitrate Uptake in Grafted Tomato Plants under High Nitrogen Demand.

Grafting has become a common practice among tomato growers to obtain vigorous plants. These plants present a substantial increase in nitrogen (N) uptake from the root zone. However, the mechanisms involved in this higher uptake capacity have not been investigated. To elucidate whether the increase in N uptake in grafted tomato plants under high N demand conditions is related to the functioning of low- (high capacity) or high-affinity (low capacity) root plasma membrane transporters, a series of experiments were conducted. Plants grafted onto a vigorous rootstock, as well as ungrafted and homograft plants, were exposed to two radiation levels (400 and 800 µmol m-2 s-1). We assessed root plasma membrane nitrate transporters (LeNRT1.1, LeNRT1.2, LeNRT2.1, LeNRT2.2 and LeNRT2.3) expression, Michaelis‒Menten kinetics parameters (Vmax and Km), root and leaf nitrate reductase activity, and root respiration rates. The majority of nitrate uptake is mediated by LeNRT1.1 and LeNRT1.2 in grafted and ungrafted plants. Under high N demand conditions, vigorous rootstocks show similar levels of expression for LeNRT1.1 and LeNRT1.2, whereas ungrafted plants present a higher expression of LeNRT1.2. No differences in the uptake capacity (evaluated as Vmax), root respiration rates, or root nitrate assimilation capacity were found among treatments.

Analysis of the Real Performance of Crumb-Rubber-Modified Asphalt Mixtures.

The main goal of this study is to evaluate the field performance of crumb-rubber-modified asphalt mixtures used as a surface layer on high-volume traffic roads. For this purpose, several road sections were constructed under different climate conditions and using control mixtures (manufactured with traditional SBS polymer-modified binders) and crumb-rubber-modified mixtures. After the construction of the different road sections, cores were taken at different periods of their service life (up to 63 months) and they were tested in the laboratory in order to assess the evolution of the density, stiffness and fatigue resistance of the layers. Based on the results obtained from tests, it can be concluded that under real severe traffic and climate conditions, asphalt mixtures manufactured with crumb-rubber-modified bitumen offer ageing and mechanical performance very similar to that offered by asphalt mixtures manufactured with traditional SBS-modified bitumen. Based on these considerations, this application can be an interesting solution to minimize environmental problems caused by end-of-life tires in landfills.

[Chilean results of the international registry of risk factors and treatment of unstable angina and non ST elevation myocardial infarction: ACCORD (ACute CORonary syndrome Descriptive study)]. / Resultados Chilenos del registro internacional de factores de riesgo y tratamiento de angina inestable e infarto al miocardio sin supradesnivel del segmento ST: ACCORD (ACute CORonary syndrome Descriptive study).

BACKGROUND: Guidelines for the management of unstable angina (UA) and non ST elevation myocardial infarction (NSTEMI) have been issued, however, current practices are unknown in Chile. AIM: To evaluate in a prospective cohort of NSTEMI patients the current practices, treatments and risk factors. MATERIAL AND METHODS: One year prospective International non interventional registry, conducted in Chile between January 2005 and November 2006. RESULTS: Two hundred thirty three Chilean NSTEMI patients were enrolled. Mortality was 5.5% at the end of the follow-up. Mean age was 61.6 years, and 30.6% were female. Most of the patients had at least one risk factor (98%): hypertension (84%), previous myocardial infarction (33%), dyslipidemia (54%), diabetes (33%), current smoking (30%). Main procedures during the hospitalization were coronary angiogram (67%), angioplasty (33%; 88% with stent) and coronary bypass surgery (7%). During procedures, 31% of patients received clopidogrel, and 4.2% glycoprotein Ilb/IIIa antagonists. Medical management was selected for 60% of patients. In comparison to men, women received less interventional procedures despite having more risk factors. Treatments prescribed at discharge were aspirin (97%), clopidogrel (49%), beta blockers (78%), diuretics (21%), lipid lowering agents (78%), oral hypoglycemic agents (13%) and insulin (9%). At the end of the 1-year follow-up, treatments were aspirin (84%), beta blockers (72%), diuretics (19%), and dual antiplatelet therapy with clopidogrel (16%). CONCLUSIONS: A high prevalence of multiple risk factors for cardiovascular disease in Chilean patients with NSTEMI was observed. More aggressive primary and secondary preventive measures are urgently needed. Use of therapies proposed in the guidelines is high, but dual antiplatelet therapy is less than 50% at discharge and decreases during the one year-follow-up.

Pharmacological inhibition and genetic deficiency of plasminogen activator inhibitor-1 attenuates angiotensin II/salt-induced aortic remodeling.

OBJECTIVE: To test the hypothesis that pharmacological plasminogen activator inhibitor (PAI)-1 inhibition protects against renin-angiotensin-aldosterone system-induced cardiovascular injury, the effect of a novel orally active small-molecule PAI-1 inhibitor, PAI-039, was examined in a mouse model of angiotensin (Ang) II-induced vascular remodeling and cardiac fibrosis. METHODS AND RESULTS: Uninephrectomized male C57BL/6J mice were randomized to vehicle subcutaneus, Ang II (1 mug/h) subcutaneous, vehicle+PAI-039 (1 mg/g chow), or Ang II+PAI-039 during high-salt intake for 8 weeks. Ang II caused significant medial, adventitial, and aortic wall thickening compared with vehicle. PAI-039 attenuated Ang II-induced aortic remodeling without altering the pressor response to Ang II. Ang II increased heart/body weight ratio and cardiac fibrosis. PAI-039 did not attenuate the effect of Ang II on cardiac hypertrophy and increased fibrosis. The effect of PAI-039 on Ang II/salt-induced aortic remodeling and cardiac fibrosis was comparable to the effect of genetic PAI-1 deficiency. Ang II increased aortic mRNA expression of PAI-1, collagen I, collagen III, fibronectin, osteopontin, monocyte chemoattractant protein-1, and F4/80; PAI-039 significantly decreased the Ang II-induced increase in aortic osteopontin expression at 8 weeks. CONCLUSIONS: This study demonstrates that pharmacological inhibition of PAI-1 protects against Ang II-induced aortic remodeling. Future studies are needed to determine whether the interactive effect of Ang II/salt and reduced PAI-1 activity on cardiac fibrosis is species-specific. In this study, the effect of pharmacological PAI-1 inhibition in a mouse model of Ang II-induced vascular remodeling and cardiac fibrosis was examined. PAI-1 inhibition significantly attenuated Ang II-induced aortic medial and wall thickening, but not cardiac hypertrophy, and enhanced Ang II/salt-induced cardiac fibrosis.

Utilidad de la imagen en multi-modalidad para el diagnóstico diferencial de las masas cardíacas / Multi-modality imaging for diagnosis and characterization of cardiac masses

Introducción: El presente trabajo es un estudio descriptivo de una serie de casos con masas cardíacas cuyo estudio involucró múltiples modalidades de imagen no invasiva, incluyendo Ecocardiograma (ECO), Tomografía Axial Computada Cardíaca (TAC), PET/CT (Tomografía de Emisión de Positrones) y Resonancia nuclear magnética (RNM) Cardíaca. Objetivo: Establecer la capacidad diagnóstica de la multa-modalidad de imagen en el estudio etiológico y localización de una masa cardíaca pesquisada inicialmente por ECO transtorácico. Método: Se realizó un análisis descriptivo de 37 casos estudiados con diversas modalidades de imagen no invasiva en Vanderbilt University Medical Center, Nashville, Tennessee, entre Julio 2014 y Julio 2015, La naturaleza de las masas fue determinada por biopsia, cirugía o seguimiento clínico. Resultados: Del total de masas, 14 (39%) fueron tumores confirmados por biopsia; 11 (30%) correspondieron a trombos; 1 caso (2.8%) fue una masa valvular infecciosa; 1 caso (2.8%) correspondió a calcificación caseosa del anillo Mitral; 1 caso (2.8%) fue variante normal y solo 1 caso (2.8%) fue indeterminado; 6 (17%) casos fueron masas de localización extracardíaca. La modalidad ECO + RNM Cardíaca fue suficiente para caracterizar localización y tipo histológico en 28 casos (76%); la modalidad ECO + TAC Cardíaca + RNM Cardíaca fue necesaria en 7 casos (19%); La modalidad ECO + TAC Cardíaca + RNM Cardíaca + PET/CT fue necesaria en 1 caso (2.5%) para la actividad mitótica celular; la modalidad ECO + RNM Cardíaca + PET/CT fue necesaria en 1 caso (2.5%) para localización, tipo histológico, calcio y actividad infecciosa. La modalidad ECO + TAC Cardíaca no permitió identificar localización, tipo histológico con calcificación y /o tejido adiposo. Conclusión: La multi-modalidad de imagen permitió identificar la etiología y localización de la masa cardíaca en el 97% de los casos. La combinación ECO + RNM Cardíaca fue la modalidad más usada. La TAC Cardíaca es particularmente útil para caracterizar calcificaciones y/o tejido adiposo y el PET/CT para caracterizar actividad metabólica (infección activa y actividad mitótica celular).

Background: We analyzed a series of patients with cardiac masses who were studied using multiple imaging modalities, including echocardiography (ECHO), CT Scan, Magnetic Resonance imaging (RNM) and PET/CT Aim: to determine the usefulness of multi-modality imaging in determining the etiology and location of cardiac masses initially detected by ECHO Methods: 37 patients selected by the presence of a cardiac mass detected by ECHO were submitted to different modalities of cardiac imaging in order to determine the nature, location and etiology of the mass Results: 14 (39%) masses were tumors confirmed by biopsy; 11 (30%) fulfilled criteria to diagnose a thrombus; 1 patient (2.8%) had an infectious cardiac mass, another calcification of the mitral an-nulus, another turned out to be a normal variant and only in one patient (2.8%) a diagnosis was not possible. Six patients had extra cardiac masses. ECHO plus RNM were sufficient to characterize location and histologic type in 28 patients (76%). Seven cases (19%) required ECHO plus CT scan. ECHO plus CT scan plus RNM plus PET/CT was required in 1 patient to establish mitotic activity. ECHO plus RNM plus PT/CT was necessary to determine location, histologic type, presence of calcium and infectious activity Conclusion: Multimodality imaging allowed to determine etiology and location of cardiac masses in 97 % of cases. ECHO plus NMR was the combination most frequently used. CT scan was particularly useful to identify calcification and fat deposits and PET/CT to identify increased metabolic activity, either infection or mitotic activity.

Hallazgos de trombos intracardíacos por cardioresonancia no diagnosticados por ecocardiograma transtorácico / Intracardiac thrombus identified by nuclear magnetic resonance not previously diagnosed by transthoracic echocardiography

La Resonancia Magnética Cardíaca permite, entre otros, una superior localización espacial y caracterización tisular de las estructuras cardíacas, muchas veces omitidas por modalidades de alto uso como el ultrasonido. Objetivo: Describir los hallazgos de trombos in-tracardíacos en una serie de pacientes enviados a estudio de resonancia cardíaca, en los cuales el ecocar-diograma transtorácico no estableció el diagnóstico de trombo. Método: Se realizó un análisis descriptivo de una serie de 62 casos, 72% hombres, entre 18 y 84 años, con disfunción sistólica severa 63%; moderada 26% y normal 11%. El 38% tenía historia presente o remota de Accidente Vascular Encefálico. Todos tenían ecocardiograma transtorácico sin trombos visibles y fueron enviados a resonancia cardíaca por estudio de cardiomiopatía no isquémica 41%; viabilidad 41% y accidente vascular encefálico isquémico sin fuente embolígena demostrada 18% El estudio se efectuó en Vanderbilt University Medical Center, entre Julio del 2014 a Julio del 2015. Resultados: Las imágenes, correspondientes a trombos cardíacos en los 62 casos, fueron localizados en ventrículo izquierdo en su gran mayoría (58 casos, 94%), orejuela de aurícula izquierda (3, 5%) y ambas orejuelas (1 caso, 1%). Los trombos fueron en su gran mayoría laminares (52 casos, 84%), sésiles (10 casos, 16%) y ninguno pediculado. Conclusión: La resonancia cardíaca es un método de imagen no invasivo muy superior a la ecocardiografía transtorácica en la identificación y localización de trombos intracardíacos, incluyendo pacientes con estudio de fuente embolígena negativos.

Cardiac Magnetic Resonance imaging allows, among others, a better localization and tissue characterization of cardiac structures, which may be missed by other imaging modalities, namely ultrasonography. Aim: to describe the finding and characteristics of intracardiac thrombus in a series of patients referred for cardiac NMR imaging, whose previous transthoracic echocardiogram had been negative for the diagnosis of this condition. Methods: the study is a description of NMR imaging findings in patients with intracardiac thrombus. There were 62 patients, 72% males, aged 18 to 64 years. LV systolic function was normal in 11%, mo-derately decreased in 26% and severely depressed in 63% of patients. A remote or a recent cerebrovas-cular accident (CVA) was present in 38% of cases. All patients had a previous transthoracic echocar-diogram with no evidence of thrombus. Patients had been referred for NMR with a diagnosis of non is-chemic cardiomyopathy (41%), study of myocardial viability (41%) and CVA with unidentified embolic source (18%). The study was performed at Vander-bilt University Medical Center, between July 2014 and July 2015.

Resultados Chilenos del registro internacional de factores de riesgo y tratamiento de angina inestable e infarto al miocardio sin supradesnivel del segmento ST: ACCORD (ACute CORonary syndrome Descriptive study) / Chilean results of the international registry of risk factors and treatment of unstable angina and non ST elevation myocardial infarction: ACCORD (ACute CORonary syndrome Descriptive study)

Background: Guidelines for the management of unstable angina (UA) and non ST elevation myocardial infarction (NSTEMI) have been issued, however cu-rrent practices are unknown in Chile. Aitn: To evalúate in a prospective cohort of NSTEMI patients the current practices, treatments and risk factors. Material and Methods: Oneyear prospective International non interventional registry, conducted in Chile between January 2005 and November 2006. Results: Two hundred thirty three Chilean NSTEMI patients were enrolled. Mortality was 5.5 percent at the end ofthe follow-up. Mean age was 61.6 years, and 30.6 percent were female. Most of the patients had at least one risk factor (98 percent): hypertension (84 percent), previous myocardial infarction (33 percent), dyslipidemia (54 percent), diabetes (33 percent), current smoking (30 percent). Main procedures duringthe hospitalization were coronary angiogram (67 percent), angioplasty (33 percent; 88 percent with stent) and coronary bypass surgery (7 percent). Duringprocedures, 31 percent of patients received clopidogrel, and 4.2 percent glycoprotein Ilb/IIIa antagonists. Medical management was selected for 60 percent of patients. In comparison to men, women received less interventional procedures despite havingmore risk factors. Treatments prescribed at discharge were aspirin (97 percent), clopidogrel (49 percent), beta blockers (78 percent), diuretics (21 percent), lipid lowering agents (78 percent), oral hypoglycemic agents (13 percent) and insulin (9 percent). At the end ofthe 1-year follow-up, treatments were aspirin (84 percent), beta blockers (72 percent), diuretics (19 percent), and dual antiplatelet therapy with clopidogrel (16 percent). Conclusions: A high prevalence of múltiple risk factors for cardiovascular disease in Chilean patients with NSTEMI was observed. More aggressive primary and secondary preventive measures are urgently needed. Use of therapies proposed in the guidelines is high, but dual antiplatelet therapy is less than 50 percent at discharge and decreases during the one year-follow-up.

Differing effects of mineralocorticoid receptor-dependent and -independent potassium-sparing diuretics on fibrinolytic balance.

This study tests the hypothesis that spironolactone influences plasminogen activator inhibitor-1 (PAI-1) concentrations through mineralocorticoid receptor antagonism rather than through changes in potassium. Effects of spironolactone (50 mg per day) and triamterene (50 mg per day) on fibrinolytic balance were compared in 18 normotensive and 20 hypertensive subjects pretreated with hydrochlorothiazide (HCTZ; 12.5 mg per day). Blood pressure and serum potassium were similar in spironolactone and triamterene treatment groups. The effect of the 2 drugs on the renin-angiotensin-aldosterone system was also similar. In contrast, spironolactone and triamterene exerted opposing effects on PAI-1 antigen (P=0.006 for drug effect). In normotensive subjects, triamterene (from 10.1+/-7.8 to 16.9+/-9.9 ng/mL at 9 am, P=0.019; from 7.6+/-5.4 to 11.5+/-7.3 ng/mL at 11 am, P=0.027; from 9.3+/-7.7 to 13.7+/-8.5 ng/mL for average of all time points, P=0.054) but not spironolactone significantly increased PAI-1 antigen. In hypertensive subjects, spironolactone significantly decreased PAI-1 antigen (from 22.0+/-23.4 to 16.7+/-19.0 ng/mL at 10 am, P=0.041; from 17.5+/-21.7 to 12.7+/-16.8 ng/mL at 11 am, P=0.043; from 20.3+/-22.6 to 16.6+/-19.7 ng/mL for average of all time points, P=0.014), whereas there was no effect of triamterene. Only spironolactone significantly decreased the molar ratio of PAI-1 to tissue-type plasminogen activator (t-PA) in hypertensive subjects. By regression analysis, predictors of mean PAI-1 response were spironolactone versus triamterene (P=0.014), hypertension (P=0.002), and PAI-1 response to HCTZ (P=0.019), with a trend for aldosterone (P=0.061). Mineralocorticoid receptor antagonism prevents the effect of activation of the renin-angiotensin-aldosterone system on PAI-1 antigen in normotensive subjects and improves fibrinolytic balance in hypertensive subjects through a potassium-independent mechanism.