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1.
Biology (Basel) ; 10(4)2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33918970

RESUMEN

Intermittent rivers and ephemeral streams (IRES) are increasingly studied because of their often-unique aquatic and terrestrial biodiversity, biogeochemical processes and associated ecosystem services. This study is the first to examine the hydrological, physicochemical and taxonomic variability during the dry-wet transition of an intermittent river in the Chilean Mediterranean Zone. Based on 30-years of river monitoring data and the TREHS tool, the hydrology of the river was characterised. Overall, the river shows a significant reduction in streamflow (-0.031 m3/s per year) and a substantial increase of zero flow days (+3.5 days per year). During the transition of hydrological states, variations were observed in the environmental conditions and invertebrate communities. During the drying phase, abundance, richness, and diversity were highest, while species turn-over was highest during base flow conditions. The disconnected pools and the flow resumption phases were characterised by high proportions of lentic taxa and non-insects, such as the endemic species of bivalves, gastropods, and crustaceans, highlighting the relevance of disconnected pools as refuges. Future climatic change scenarios are expected to impact further the hydrology of IRES, which could result in the loss of biodiversity. Biomonitoring and conservation programmes should acknowledge these important ecosystems.

2.
Environ Pollut ; 251: 90-101, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31071637

RESUMEN

In the last twenty years, pesticide use in Chile has increased more than 160%, generating a greater risk of water resources pollution. The objective of this study was to assess the presence of 22 pesticides and 12 degradation products in surface water samples from the Cachapoal River basin, Central Chile, an area characterized by intense agricultural activity. Pesticide concentrations in the dissolved phase (DP) and particulate phase (PP) in samples collected in the dry season and after precipitation events was assessed. The solid-phase extraction technique was used to preconcentrate the samples and GC/MS and LC/MS were used to detect pesticides. The results present spatio-temporal variations in the proportion and concentration of pesticides and their degradation products in both the DP and PP for each site and sampling period. The most ubiquitous compounds in the dissolved phase were atrazine, atrazine-2-hydroxy (HA), cyprodinil, pyrimethanil, and tebuconazole, while in the particulate phase HA, imidacloprid, diazinon and pyrimidinol were detected. The results presented in this study make up the first record of pesticides in the dissolved and particulate phases in surface water in Chile. They show that the problem of pesticide contamination undoubtedly affects the quality of bodies of water in agricultural areas in Chile and support the need for a proper assessment of the water quality of the Cachapoal River in the future.


Asunto(s)
Monitoreo del Ambiente , Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Agricultura , Atrazina , Chile , Cromatografía de Gases y Espectrometría de Masas , Neonicotinoides , Nitrocompuestos , Ríos/química , Estaciones del Año , Extracción en Fase Sólida , Agua/química
3.
Circ Res ; 121(10): 1192-1204, 2017 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-28974553

RESUMEN

RATIONALE: Umbilical cord-derived mesenchymal stem cells (UC-MSC) are easily accessible and expanded in vitro, possess distinct properties, and improve myocardial remodeling and function in experimental models of cardiovascular disease. Although bone marrow-derived mesenchymal stem cells have been previously assessed for their therapeutic potential in individuals with heart failure and reduced ejection fraction, no clinical trial has evaluated intravenous infusion of UC-MSCs in these patients. OBJECTIVE: Evaluate the safety and efficacy of the intravenous infusion of UC-MSC in patients with chronic stable heart failure and reduced ejection fraction. METHODS AND RESULTS: Patients with heart failure and reduced ejection fraction under optimal medical treatment were randomized to intravenous infusion of allogenic UC-MSCs (Cellistem, Cells for Cells S.A., Santiago, Chile; 1×106 cells/kg) or placebo (n=15 per group). UC-MSCs in vitro, compared with bone marrow-derived mesenchymal stem cells, displayed a 55-fold increase in the expression of hepatocyte growth factor, known to be involved in myogenesis, cell migration, and immunoregulation. UC-MSC-treated patients presented no adverse events related to the cell infusion, and none of the patients tested at 0, 15, and 90 days presented alloantibodies to the UC-MSCs (n=7). Only the UC-MSC-treated group exhibited significant improvements in left ventricular ejection fraction at 3, 6, and 12 months of follow-up assessed both through transthoracic echocardiography (P=0.0167 versus baseline) and cardiac MRI (P=0.025 versus baseline). Echocardiographic left ventricular ejection fraction change from baseline to month 12 differed significantly between groups (+7.07±6.22% versus +1.85±5.60%; P=0.028). In addition, at all follow-up time points, UC-MSC-treated patients displayed improvements of New York Heart Association functional class (P=0.0167 versus baseline) and Minnesota Living with Heart Failure Questionnaire (P<0.05 versus baseline). At study completion, groups did not differ in mortality, heart failure admissions, arrhythmias, or incident malignancy. CONCLUSIONS: Intravenous infusion of UC-MSC was safe in this group of patients with stable heart failure and reduced ejection fraction under optimal medical treatment. Improvements in left ventricular function, functional status, and quality of life were observed in patients treated with UC-MSCs. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov/ct2/show/NCT01739777. Unique identifier: NCT01739777.


Asunto(s)
Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/terapia , Trasplante de Células Madre Mesenquimatosas/métodos , Cordón Umbilical/trasplante , Anciano , Movimiento Celular/fisiología , Método Doble Ciego , Femenino , Humanos , Infusiones Intravenosas , Masculino , Células Madre Mesenquimatosas/fisiología , Persona de Mediana Edad , Resultado del Tratamiento
4.
Rev Med Chil ; 143(4): 415-23, 2015 Apr.
Artículo en Español | MEDLINE | ID: mdl-26204531

RESUMEN

BACKGROUND: Intracoronary delivery of autologous bone marrow mononuclear cells is an interesting therapeutic promise for patients with heart failure of different etiologies. AIM: To evaluate the long-term safety and efficacy of this therapy in patients with dilated cardiomyopathy of different etiologies under optimal medical treatment. PATIENTS AND METHODS: Prospective, open-label, controlled clinical trial. Of 23 consecutive patients, 12 were assigned to autologous bone marrow mononuclear cell intracoronary transplantation, receiving a mean dose of 8.19 ± 4.43 x 10(6) CD34+ cells. Mortality, cardiovascular readmissions and cancer incidence rate, changes in functional capacity, quality of life questionnaires and echocardiographic measures from baseline, were assessed at long-term follow-up (37.7 ± 9.7 months) in patients receiving or not the cells. RESULTS: No significant differences were observed in mortality, cardiovascular readmissions or cancer incidence rate amongst groups. An improvement in functional class and quality of life questionnaires in the transplanted group was observed (p < 0.01). The treated group showed a non-significant increase in left ventricular ejection fraction at long-term follow-up (from 26.75 ± 4.85% to 34.90 ± 8.57%, p = 0.059 compared to baseline). There were no changes in left ventricular volumes. We observed no improvement of these variables in the control group. CONCLUSIONS: Intracoronary transplantation of autologous bone marrow mononuclear cells is feasible and safe in patients with dilated cardiomyopathy of diverse etiologies. This therapy was associated to persistent improvements in functional class and quality of life. There was also a non-significant long-term improvement of left ventricular function.


Asunto(s)
Trasplante de Médula Ósea/métodos , Cardiomiopatía Dilatada/cirugía , Trasplante de Médula Ósea/mortalidad , Volumen Cardíaco/fisiología , Cardiomiopatía Dilatada/diagnóstico por imagen , Cardiomiopatía Dilatada/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Readmisión del Paciente/estadística & datos numéricos , Estudios Prospectivos , Calidad de Vida , Volumen Sistólico/fisiología , Encuestas y Cuestionarios , Factores de Tiempo , Trasplante Autólogo , Resultado del Tratamiento , Ultrasonografía , Función Ventricular/fisiología
5.
Rev. méd. Chile ; 143(4): 415-423, abr. 2015. ilus, tab
Artículo en Español | LILACS | ID: lil-747546

RESUMEN

Background: Intracoronary delivery of autologous bone marrow mononuclear cells is an interesting therapeutic promise for patients with heart failure of different etiologies. Aim: To evaluate the long-term safety and efficacy of this therapy in patients with dilated cardiomyopathy of different etiologies under optimal medical treatment. Patients and Methods: Prospective, open-label, controlled clinical trial. Of 23 consecutive patients, 12 were assigned to autologous bone marrow mononuclear cell intracoronary transplantation, receiving a mean dose of 8.19 ± 4.43 x 10(6) CD34+ cells. Mortality, cardiovascular readmissions and cancer incidence rate, changes in functional capacity, quality of life questionnaires and echocardiographic measures from baseline, were assessed at long-term follow-up (37.7 ± 9.7 months) in patients receiving or not the cells. Results: No significant differences were observed in mortality, cardiovascular readmissions or cancer incidence rate amongst groups. An improvement in functional class and quality of life questionnaires in the transplanted group was observed (p < 0.01). The treated group showed a non-significant increase in left ventricular ejection fraction at long-term follow-up (from 26.75 ± 4.85% to 34.90 ± 8.57%, p = 0.059 compared to baseline). There were no changes in left ventricular volumes. We observed no improvement of these variables in the control group. Conclusions: Intracoronary transplantation of autologous bone marrow mononuclear cells is feasible and safe in patients with dilated cardiomyopathy of diverse etiologies. This therapy was associated to persistent improvements in functional class and quality of life. There was also a non-significant long-term improvement of left ventricular function.


Asunto(s)
Femenino , Humanos , Masculino , Persona de Mediana Edad , Trasplante de Médula Ósea/métodos , Cardiomiopatía Dilatada/cirugía , Trasplante de Médula Ósea/mortalidad , Volumen Cardíaco/fisiología , Cardiomiopatía Dilatada/mortalidad , Cardiomiopatía Dilatada , Estudios de Seguimiento , Readmisión del Paciente/estadística & datos numéricos , Estudios Prospectivos , Calidad de Vida , Volumen Sistólico/fisiología , Encuestas y Cuestionarios , Factores de Tiempo , Trasplante Autólogo , Resultado del Tratamiento , Función Ventricular/fisiología
6.
Rev Med Chil ; 142(8): 1034-46, 2014 Aug.
Artículo en Español | MEDLINE | ID: mdl-25424676

RESUMEN

Available medical therapy is unable to completely prevent or revert the pathological cardiac remodeling secondary to ischemia or other injuries, which is responsible for the development of heart failure. Regenerative medicine through stem cells had an explosive development in the cardiovascular area during the past decade. Stem cells possess the capacity to regenerate, repair or substitute damaged tissue, allowing the reestablishment of its function. Stem cells can also modulate apoptosis, angiogenesis, fibrosis and inflammation, favoring the endogenous regenerative process initiated by the damaged tissue. These capacities have been corroborated in several animal models of cardiovascular diseases with positive results. In humans, therapies with bone marrow mononuclear stem cells, mesenchymal stem cells and cardiac stem cells are safe. Most randomized clinical trials in patients with myocardial infarction or cardiomyopathies of different etiologies have reported benefits on ventricular function, quality of life and even over mortality of treated patients. This article reviews the state of art of stem cell therapy in cardiovascular diseases, focusing on the most common cellular types used in patients with acute myocardial infarction and chronic cardiomyopathies of different etiologies.


Asunto(s)
Enfermedades Cardiovasculares/cirugía , Trasplante de Células Madre/métodos , Transdiferenciación Celular , Enfermedad Crónica , Cardiopatías/cirugía , Humanos , Células Madre Multipotentes/fisiología , Células Madre Multipotentes/trasplante , Infarto del Miocardio/cirugía
7.
Rev. méd. Chile ; 142(8): 1034-1046, ago. 2014. ilus, graf, tab
Artículo en Español | LILACS | ID: lil-728352

RESUMEN

Available medical therapy is unable to completely prevent or revert the pathological cardiac remodeling secondary to ischemia or other injuries, which is responsible for the development of heart failure. Regenerative medicine through stem cells had an explosive development in the cardiovascular area during the past decade. Stem cells possess the capacity to regenerate, repair or substitute damaged tissue, allowing the reestablishment of its function. Stem cells can also modulate apoptosis, angiogenesis, fibrosis and inflammation, favoring the endogenous regenerative process initiated by the damaged tissue. These capacities have been corroborated in several animal models of cardiovascular diseases with positive results. In humans, therapies with bone marrow mononuclear stem cells, mesenchymal stem cells and cardiac stem cells are safe. Most randomized clinical trials in patients with myocardial infarction or cardiomyopathies of different etiologies have reported benefits on ventricular function, quality of life and even over mortality of treated patients. This article reviews the state of art of stem cell therapy in cardiovascular diseases, focusing on the most common cellular types used in patients with acute myocardial infarction and chronic cardiomyopathies of different etiologies.


Asunto(s)
Humanos , Enfermedades Cardiovasculares/cirugía , Trasplante de Células Madre/métodos , Transdiferenciación Celular , Enfermedad Crónica , Cardiopatías/cirugía , Células Madre Multipotentes/fisiología , Células Madre Multipotentes/trasplante , Infarto del Miocardio/cirugía
8.
Rev. chil. cardiol ; 29(2): 193-198, ago. 2010. ilus
Artículo en Español | LILACS | ID: lil-577265

RESUMEN

Resumen: Antecedentes: El acceso radial es una alternativa aceptable y segura para procedimientos endovasculares. Sin embargo no existe una clara evaluación de la integridad de la arteria radial (AR) post procedimiento. Objetivo: Evaluar el impacto funcional y estructural a largo plazo de la punción y colocación del introductor vascular en arteria radial (AR) post intervencionismo coronario. Método: Se estudian 33 pacientes con cardiopatía coronaria a quienes se realizó coronadografía y/o angioplastía vía radial. A los 6-10 meses de seguimiento se analizó las características ecográficas funcionales y estructurales de la AR comparándola con la AR contralateral. Resultados: Con el seguimiento se observan 3 AR ocluidas (9 por ciento). No se encontró un aumento significativo del grosor de la pared a nivel distal (zona de punción), 0,36 +/- 0,22 vs 0,28 +/- 0,08mm; el diámetro fue similar a nivel distal 2,6 +/- 0,7mm vs 2,8 +/- 0,35mm (ns) y proximal 2,8 +/- 0,35 vs 2,5 +/- 0,7mm. No hay diferencia significativa en la velocidad peak sistólica (VPS), en la AR puncionada vs la control 54 +/- 16 vs 50 +/- 14 cm/seg ni en los índices de resistencia 0,83 +/- 0,1 vs 0,87 +/-0,1. Conclusiones: La utilización de la vía radial para intervencionismo coronario ocasiona en un bajo porcentaje la oclusión esta arteria. En las arterias que permanecen permeables no se encontró a largo plazo un impacto sobre las características estructurales ni funcionales.


Background: the radial artery is a common and safe access site for endovascular procedures. There has been no adequate evaluation of the radial artery integrity following the procedure. Aim: to evaluate the long term functional and structural status of the radial artery use for cardiac interventional procedures Methods: 33 patients with coronary artery disease had coronary angiography and/or PTCA using the radial artery approach. After 6-10 months the functional and structural status of the artery was evaluated by comparison to the contra lateral artery Results: Three (9 percent) arteries were occluded. No thickening of the arterial wall distal to the puncture site was observed. Diameters were 2.6 +/- 0.7 vs 2.8 +/- 0.35mm (punctured vs control) distally and 2.8 +/- 0.35 vs 2.5 +/- 0.7mm proximally. Respective peak systolic flow velocities were 54 +/- 16 vs 50 +/- 14 cm/sec (NS) and resistance indexes were 0.83+/-0.1 compared to 0.67+/-0.1 (NS) Conclusion: A low percent of radial arterial occlusion is observed following use of the radial artery following cardiovascular interventions. Patent arteries showed no structural or functional limitations at long term evaluation.


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Angiografía Coronaria/métodos , Angioplastia/métodos , Arteria Radial , Cateterismo Cardíaco/métodos , Enfermedad de la Arteria Coronaria , Enfermedad de la Arteria Coronaria/terapia , Arteria Radial/fisiología , Estudios de Seguimiento
9.
Rev. chil. cardiol ; 29(3): 299-305, 2010. ilus, tab
Artículo en Español | LILACS | ID: lil-592017

RESUMEN

Antecedentes: El intervencionismo en las oclusiones totales crónicas (OTC) requiere técnicas complejas y el éxito es poco predecible. Es útil identificar la efectividad de las guías de cruce y del balón para el intervencionismo en distintos niveles de complejidad de OTC. Objetivos: Evaluar la efectividad de cruce de distintas guías y balones en el tratamiento de OTC. Métodos: Se revisa en forma retrospectiva la efectividad de distintos tipos de guías y balones de cruce utilizados en intervencionismo de OTC efectuados entre agosto de 2007 y agosto de 2009. Se define "efectividad" como la capacidad de avanzar y cruzar la oclusión crónica con la guía y el balón, ambas necesarias para efectuar la angioplastia de la OTC. Se agrupan los resultados según el nivel de complejidad de la OTC de acuerdo a score propio, distinguiendo entre OTC simples, complejas y de alta complejidad. Resultado: En el período estudiado se revisan 90 OTC. Se utilizan 148 guías (1,6 guía/proc.) y se utilizan 92 balones en 76 procedimiento que logran paso efectivo de guía. (1,2 bal/proc). Se realiza una tabla con la tasa de efectividad de distintas guías y balones de cruce. Destaca la utilidad de guía PT2 en lesiones simples y complejas, como la utilidad de la guía Miracle 6 en OTC de alta complejidad. Conclusiones: En OTC se obtiene un éxito de 67 por ciento en nuestro medio, con mayor efectividad de la guía PT2 en lesiones simples y complejas y de Miracle 6 en lesiones de alta complejidad. En cuanto a balones se obtiene mayor efectividad en los tipo Maverick, Mercury y Voyaguer de 1,5 mm en lesiones simples y complejas, como del Balón Maverick de 1,5 mm en lesiones de alta complejidad. Es de gran utilidad un registro de la efectividad de balones y guías en el tratamiento de OTC, lo que permite al intervencionista una adecuada elección del material con el consecuente ahorro de tiempo y mayor efectividad del procedimiento.


Background.: PCI in chronic coronary occlusions requires complex techniques and is associated to less predictable results. It is important to evaluate the effectiveness of different guides and balloons in PCI for total coronary occlusion (TCO). Aim: To evaluate the effectiveness of different guides and balloons in the treatment of TCO. Methods: A retrospective review of the effectiveness of different guides and balloons in the treatment of TCO performed from 2007 to 2009 was carried out Effectiveness was defined as the ability to traverse the occlusion with the guide and the balloon. The analysis was performed according to groups defined by the complexity of the TCO as assessed by a locally developed score. Occlusions were classified as simple, complex or highly complex. Results: 90 procedures were analyzed 148 guides were utilized (mean of 1.6 per procedure) and 92 balloons were used in 76 cases were the guide successfully crossed the occlusion. The PT2 guide was effective for simple and complex lesions, whereas de Miracle 6 guide was effective in the treatment of highly complex lesions. Regarding balloons, the Maverick, Mercury and Voyageur 1.5 mm were satisfactory in simple and complex lesions, while the Maverick 1.5mm was more effective in highly complex lesions Conclusion: TCO was successfully treated by PCI in 67 percent of cases. PT2 guides and all types of balloons were effective for treatment of simple and complex lesions. In contrast, the Miracle 6 guide and the Maverick 1.5 balloon were more effective in highly complex lesions. These findings may be useful to help de proper selection of angioplasty materials when treating.


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Angioplastia Coronaria con Balón/métodos , Estenosis Coronaria/terapia , Enfermedad Crónica , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
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