367 research outputs found
Is hypertension without any other comorbidities an independent predictor for COVID-19 severity and mortality?
Early reports from China found that both established cardiovascular disease and its risk factors, such as hypertension and diabetes mellitus, were common pre-existing conditions in patients with COVID- 19. The high prevalence of these comorbidities was confirmed in subsequent studies. Remarkably, the prevalence of these pre-existing conditions was higher in critically ill patients and in those who died. In the analysis performed by Wu and McGoogan, including 44 672 patients with confirmed COVID-19, the overall case fatality rate was 2.3%, and increased with comorbid conditions: 10.5% for cardiovascular disease, 7.3% for diabetes, and 6% for hypertension. The connections between cardiovascular disease, hypertension, age, and vascular aging are complex. The association between hypertension and COVID-19 mortality or severity could be explained in part by the increased age and higher prevalence of cardiovascular disease, both well-known risk factors for mortality in critical patients.
Therefore, in order to identify independent predictors of COVID-19 mortality or severity, models should be properly adjusted to exclude potential confounding effects.Facultad de Ciencias Médica
Comparison of two surrogate estimates of insulin resistance to predict cardiovascular disease in apparently healthy individuals
Background and aims: Insulin resistance is associated with a cluster of abnormalities that increase cardiovascular disease (CVD). Several indices have been proposed to identify individuals who are insulin resistant, and thereby at increased CVD risk. The aim of this study was to compare the abilities of 3 indices to accomplish that goal: 1) plasma triglyceride × glucose index (TG × G); 2) plasma triglyceride/high-density lipoprotein cholesterol ratio (TG/HDL-C); and 3) Metabolic Syndrome (MetS).
Methods and results: In a population sample of 723 individuals (486 women and 237 men, 50 ± 16 and 51 ± 16 years old, respectively), baseline demographic and metabolic variables known to increase CVD risk and incident CVD were compared among individuals defined as high vs. low risk by: TG × G; TG/HDL-C; or MetS. CVD risk profiles appeared comparable in high risk subjects, irrespective of criteria. Crude incidence of CVD events was increased in high risk subjects: 12.2 vs. 5.3% subjects/10 years, p = 0.005 defined by TG/HDL-C; 13.4 vs. 5.3% subjects/10 years, p = 0.002 defined by TG × G; and 13.4% vs. 4.5% of subjects/10 years, p < 0.001 in subjects with the MetS. The area under the ROC curves to predict CVD were similar, 0.66 vs. 0.67 for TG/HDL-C and TG × G, respectively. However, when adjusted by age, sex and multiple covariates, hazard ratios for incident CVD were significantly increased in high risk patients classified by either TG/HDL-C ratio (2.18, p = 0.021) or MetS (1.93, p = 0.037), but not by TG × G index (1.72, p = 0.087).
Conclusion: Although the 3 indices identify CVD risk comparably, the TG × G index seems somewhat less effective at predicting CVD.Facultad de Ciencias Médica
Estenosis aórtica severa: ¿qué ves cuando me ves?
Aortic stenosis is the most frequent valve disease in the world and its incidence increases with the aging of the population. The echocardiogram is a useful tool for the non-invasive evaluation of patients with aortic valve stenosis in all its stages of evolution.La estenosis aórtica es la valvulopatía más frecuente en el mundo y su incidencia se incrementa con el envejecimiento de la población. El ecocardiograma es una herramienta útil para la evaluación no invasiva de pacientes con estenosis valvular aórtica en todas sus fases de evolución
Effect Of Nb And Cu On The Crystallization Behavior Of Understoichiometric Nd–Fe–B Alloys
In this work, we present a complete study of the influence of Nb and Cu addition on the crystallization behavior of Nd-lean Nd-Fe-B melt-spun alloys. Alloys with compositions Nd10-x-yFe84B6NbxCuy (x = 1, y = 0 and x = 0.5, y = 0.5) were melt-spun at different wheel speeds (15-40 m s(-1)) to obtain samples in amorphous, highly disordered and nanocrystalline structures. The crystallization process, induced by different heat treatments, was studied by means of differential thermal analysis and x-ray powder thermodiffraction. Magnetic properties of as-made and heat-treated ribbons were measured by magnetometry. The as-made amorphous samples showed a crystallization to the 2: 14: 1 hard magnetic phase at T-1 similar to 350 degrees C. Doping with Nb results in an increase of T1, and addition of Cu lowers T1. This behavior is explained in terms of an inhibition of grain growth by Nb and a nucleation enhancement by Cu additions. During the crystallization process, a secondary phase (identified as a bcc-Fe-rich phase) is formed. The amount of such a phase increases with the annealing temperature. Coercivity increases upon annealing reaching maxima at 700-750 degrees C. This can be explained in terms of competition between the two phases formed: the 2: 14: 1 hard phase and the soft bcc-Fe-rich phase. The highest coercivity of the Nd-lean samples is observed when the microstructure is appropriate and both phases are exchange-coupled.This work has received funding from the DOE BES-DE-FG02-90ER45413 and the European Union MSCA grant agreement No 691235 (INAPEM). Technical and human support provided by SGIker (UPV/EHU, GV/EJ and ESF) is gratefully acknowledged
New insights on the seismogenic potential of the Eastern Betic Shear Zone (SE Iberia): Quaternary activity and paleoseismicity of the SW segment of the Carrascoy Fault Zone
The Carrascoy Fault (CAF) is one of the main active faults that form part of the Eastern Betic Shear Zone, a 450 km fault system that accommodates most of the convergence between the Eurasian (Iberia) and Nubian plates in the Betic Cordillera, south Spain. Although the CAF represents a major earthquake threat to the nearby City of Murcia, studies on its Quaternary tectonics and seismogenic potential are scarce to date. We present evidence that supports the division of the CAF into two overlapping segments with contrasting tectonic structure, Quaternary activity, and landform control: a SW segment, characterized by a broad fold-and-thrust zone similar to the forebergs defined in the Gobi-Altai region, and a NE segment, characterized by a sharp mountain front controlled by strike-slip tectonics. We attribute the differentiation into these two segments to the stresses associated with topography, which in turn is a consequence of the shortening component, at the middle Pleistocene, after circa 217.4 ka. For the SW segment we infer the occurrence of 9 to 11, Mw 6.7 paleoearthquakes in the last 30.2 kyr, and a slip rate of 0.37 ± 0.08 m/kyr. We date the occurrence of the last surface rupture event after 2750 B.P., and we estimate an average recurrence period of major events of 3.3 ± 0.7 kyrThis work was supported by SISMOGEN (IGME, 2279) and FASEGEO (CGL2009-09726) research projects and a technical assistance of the Civil Protection Service of Murci
Paleoseismological evidence of holocene activity of the Los Tollos fault (Murcia, se Spain): a lately formed quaternary tectonic feature of the eastern betic shear zone
The Los Tollos Fault is a recent and important feature of the Eastern Betic Shear Zone, one of the major tectonic structures in South Iberia accommodating the convergence between Nubian and Eurasian plates in the western Mediterranean. The Los Tollos Fault became active by the end of Middle Pleistocene introducing some paleogeographical modifications. Previously mapped as a secondary normal fault related to the Carrascoy Fault, recent research evidences that the Los Tollos Fault is an independent Holocene active left-lateral reverse fault extending for at least 15 km. Data analysis from 4 trenches dug across the fault has revealed the occurrence of at least two paleo-earthquake events during the Holocene. The most recent event is dated between 2,740 and 2,140 yr BP (8th to 2nd centuries BC). The size of the paleoevents is calculated to be Mw 6.3 – 6.6 following empirical regressions on surface rupture length. The recurrence interval is estimated to be between 2,200-6,860 years, fitting a slip rate for the fault between 0.12 and 0.17 mm/yr. Such parameters highlight the Los Tollos Fault as a tectonic structure with a considerable activity located relatively close to densely populated areas. These seismogenic parameters should be considered in future reassessments of the seismic hazard of the regionThis work forms part of the research activities carried out in the FASEGEO Project (CGL2009-09726) funded by the Spanish Ministry of Science and Innovatio
Paleoseismological evidence of Holocene activity of the Los Tollos Fault (Murcia, SE Spain): A lately formed Quaternary tectonic feature of the Eastern Betic Shear Zone
[EN] The Los Tollos Fault is a recent and important feature of the Eastern Betic Shear Zone, one of the major tectonic structures in South
Iberia accommodating the convergence between Nubian and Eurasian plates in the western Mediterranean. The Los Tollos Fault became
active by the end of Middle Pleistocene introducing some paleogeographical modifications. Previously mapped as a secondary normal fault
related to the Carrascoy Fault, recent research evidences that the Los Tollos Fault is an independent Holocene active left-lateral reverse fault
extending for at least 15 km. Data analysis from 4 trenches dug across the fault has revealed the occurrence of at least two paleo-earthquake
events during the Holocene. The most recent event is dated between 2,740 and 2,140 yr BP (8th to 2nd centuries BC). The size of the paleoevents
is calculated to be Mw 6.3 – 6.6 following empirical regressions on surface rupture length. The recurrence interval is estimated to be
between 2,200-6,860 years, fitting a slip rate for the fault between 0.12 and 0.17 mm/yr. Such parameters highlight the Los Tollos Fault as
a tectonic structure with a considerable activity located relatively close to densely populated areas. These seismogenic parameters should
be considered in future reassessments of the seismic hazard of the region.[ES] La falla de Los Tollos es una estructura reciente e importante de la Zona de Cizalla de la Bética Oriental, la principal estructura del sureste
de la Península Ibérica que acomoda gran parte de la convergencia entre las placas de Eurasia y Nubia en el Mediterráneo Occidental. La
falla de Los Tollos, descrita inicialmente como una falla normal secundaria relacionada con la falla de Carrascoy, comenzó su actividad a
finales del Pleistoceno Medio generando algunas modificaciones paleogeográficas significativas. El trabajo que aquí presentamos demuestra
su activad durante el Holoceno con una cinemática lateral sinestral con componente inversa a lo largo de una longitud de 15 km, e independiente
de la Falla de Carrascoy. Del análisis de los datos obtenidos en 4 trincheras paleosismológicas realizadas a lo largo de la traza de
la falla, se han podido interpretar la ocurrencia de al menos 2 paleoterremotos durante el Holoceno, acotándose el evento más reciente entre
hace 2.740 y 2.140 años (siglos VIII a II a.C.). La magnitud máxima de estos paleoterremotos, estimada mediante correlaciones empíricas
que consideran la longitud de rotura en superficie de la falla, se encuentra entre Mw 6,3 y 6,6, con un periodo de recurrencia comprendido
entre 2.200 y 6.860 años. La tasa de deslizamiento neta calculada para la falla se estima entre 0,12 y 0,17 mm/a. Estos parámetros identifican
la falla de Los Tollos como una estructura activa situada en las cercanías de áreas densamente pobladas y ponen de manifiesto el interés
que tendría considerarla en futuras reevaluaciones de la peligrosidad sísmica en la región.FASEGEO Project (CGL2009-09726) funded by the
Spanish Ministry of Science and Innovation.Peer reviewe
Paleoseismological evidence of Holocene activity of the Los Tollos Fault (Murcia, SE Spain): A lately formed Quaternary tectonic feature of the Eastern Betic Shear Zone
The Los Tollos Fault is a recent and important feature of the Eastern Betic Shear Zone, one of the major tectonic structures in South Iberia accommodating the convergence between Nubian and Eurasian plates in the western Mediterranean. The Los Tollos Fault became active by the end of Middle Pleistocene introducing some paleogeographical modifications. Previously mapped as a secondary normal fault related to the Carrascoy Fault, recent research evidences that the Los Tollos Fault is an independent Holocene active left-lateral reverse fault extending for at least 15 km. Data analysis from 4 trenches dug across the fault has revealed the occurrence of at least two paleo-earthquake events during the Holocene. The most recent event is dated between 2,740 and 2,140 yr BP (8th to 2nd centuries BC). The size of the paleoevents is calculated to be Mw 6.3 – 6.6 following empirical regressions on surface rupture length. The recurrence interval is estimated to be between 2,200-6,860 years, fitting a slip rate for the fault between 0.12 and 0.17 mm/yr. Such parameters highlight the Los Tollos Fault as a tectonic structure with a considerable activity located relatively close to densely populated areas. These seismogenic parameters should be considered in future reassessments of the seismic hazard of the region.La falla de Los Tollos es una estructura reciente e importante de la Zona de Cizalla de la Bética Oriental, la principal estructura del sureste de la Península Ibérica que acomoda gran parte de la convergencia entre las placas de Eurasia y Nubia en el Mediterráneo Occidental. La falla de Los Tollos, descrita inicialmente como una falla normal secundaria relacionada con la falla de Carrascoy, comenzó su actividad a finales del Pleistoceno Medio generando algunas modificaciones paleogeográficas significativas. El trabajo que aquí presentamos demuestra su activad durante el Holoceno con una cinemática lateral sinestral con componente inversa a lo largo de una longitud de 15 km, e independiente de la Falla de Carrascoy. Del análisis de los datos obtenidos en 4 trincheras paleosismológicas realizadas a lo largo de la traza de la falla, se han podido interpretar la ocurrencia de al menos 2 paleoterremotos durante el Holoceno, acotándose el evento más reciente entre hace 2.740 y 2.140 años (siglos VIII a II a.C.). La magnitud máxima de estos paleoterremotos, estimada mediante correlaciones empíricas que consideran la longitud de rotura en superficie de la falla, se encuentra entre Mw 6,3 y 6,6, con un periodo de recurrencia comprendido entre 2.200 y 6.860 años. La tasa de deslizamiento neta calculada para la falla se estima entre 0,12 y 0,17 mm/a. Estos parámetros identifican la falla de Los Tollos como una estructura activa situada en las cercanías de áreas densamente pobladas y ponen de manifiesto el interés que tendría considerarla en futuras reevaluaciones de la peligrosidad sísmica en la región
Nocturnal but not Diurnal Hypertension Is Associated to Insulin Resistance Markers in Subjects with Normal or Mildly Elevated Office Blood Pressure
Objective: The aim was to evaluate the relationships among insulin resistance markers and nocturnal and diurnal hypertension in normotensive or mildly untreated hypertensive adults.
Methods: The study was performed in both female and male adults referred to the Cardiometabolic Unit of the Hospital San Martín, La Plata, Argentina, in order to perform an ambulatory blood pressure measurement (ABPM) for the evaluation of a possible hypertensive disorder. The population was stratified according to their ABPM in: 1-presence or absence of diurnal hypertension and 2-presence or absence of nocturnal hypertension; both conditions were analyzed separately. Fasting plasma insulin (FPI), homeostasis model assessment of insulin resistance (HOMA-IR), and triglycerides (TG)/high-density lipoprotein cholesterol (HDL-C) ratio were used as surrogate markers of insulin resistance and compared among subjects with vs. without diurnal or nocturnal hypertension.
Results: One hundred and five patients, 55 women, 47 (11) years old, and 50 men, 44 (16) years old, were included. Diurnal and nocturnal hypertension were found in 60% and 64% of the sample, respectively. There were no significant differences among the levels of insulin resistance markers between individuals with or without diurnal hypertension. In contrast, individuals with nocturnal hypertension were more insulin resistant irrespectively of whether they were evaluated using FPI (P = 0.016), HOMA-IR (P = 0.019), or TG/HDL-C ratio (P = 0.011); FPI differences remained significant after adjustment for sex, age, and obesity indicators (P = 0.032).
Conclusions: Nocturnal but not diurnal hypertension was related to higher levels of 3 insulin resistance markers in normotensive and untreated mildly hypertensive adults; this relationship seems partially independent of obesity.Facultad de Ciencias Médica
Nocturnal but not Diurnal Hypertension Is Associated to Insulin Resistance Markers in Subjects with Normal or Mildly Elevated Office Blood Pressure
Objective: The aim was to evaluate the relationships among insulin resistance markers and nocturnal and diurnal hypertension in normotensive or mildly untreated hypertensive adults.
Methods: The study was performed in both female and male adults referred to the Cardiometabolic Unit of the Hospital San Martín, La Plata, Argentina, in order to perform an ambulatory blood pressure measurement (ABPM) for the evaluation of a possible hypertensive disorder. The population was stratified according to their ABPM in: 1-presence or absence of diurnal hypertension and 2-presence or absence of nocturnal hypertension; both conditions were analyzed separately. Fasting plasma insulin (FPI), homeostasis model assessment of insulin resistance (HOMA-IR), and triglycerides (TG)/high-density lipoprotein cholesterol (HDL-C) ratio were used as surrogate markers of insulin resistance and compared among subjects with vs. without diurnal or nocturnal hypertension.
Results: One hundred and five patients, 55 women, 47 (11) years old, and 50 men, 44 (16) years old, were included. Diurnal and nocturnal hypertension were found in 60% and 64% of the sample, respectively. There were no significant differences among the levels of insulin resistance markers between individuals with or without diurnal hypertension. In contrast, individuals with nocturnal hypertension were more insulin resistant irrespectively of whether they were evaluated using FPI (P = 0.016), HOMA-IR (P = 0.019), or TG/HDL-C ratio (P = 0.011); FPI differences remained significant after adjustment for sex, age, and obesity indicators (P = 0.032).
Conclusions: Nocturnal but not diurnal hypertension was related to higher levels of 3 insulin resistance markers in normotensive and untreated mildly hypertensive adults; this relationship seems partially independent of obesity.Facultad de Ciencias Médica
- …