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2.
J Med Case Rep ; 18(1): 109, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38383477

RESUMEN

BACKGROUND: While noninvasive imaging is typically used during the initial assessment of carotid artery disease, digital subtraction angiography remains the gold standard for evaluating carotid stent thrombosis and stenosis (Krawisz in Cardiol Clin 39:539-549, 2021). This case highlights the importance of digital subtraction angiography for assessing carotid artery stent patency in place of non-invasive imaging. CASE PRESENTATION: We present a 61-year-old African American male patient with a history of right cervical internal carotid artery dissection that was treated with carotid artery stenting and endovascular thrombectomy, who developed recurrent right hemispheric infarcts related to delayed carotid stent thrombosis. Digital subtraction angiography found multiple filling defects consistent with extensive in-stent thrombosis not clearly observed with magnetic resonance angiography. Etiology was likely secondary to chronic antiplatelet noncompliance. Therefore, the patient was treated medically with a heparin drip, and dual antiplatelet therapy (dAPT) was restarted. At 1-month follow-up the patient did not report new motor or sensory deficits. CONCLUSION: In the setting of delayed carotid stent thrombosis secondary to antiplatelet noncompliance, digital subtraction angiography may play an essential diagnostic role for early identification and determination of the most appropriate treatment.


Asunto(s)
Estenosis Carotídea , Trombosis , Humanos , Masculino , Persona de Mediana Edad , Stents/efectos adversos , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/cirugía , Angiografía Cerebral , Trombosis/diagnóstico por imagen , Trombosis/etiología , Arteria Carótida Interna/diagnóstico por imagen , Angiografía de Substracción Digital
4.
Nat Plants ; 9(11): 1810-1817, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37845335

RESUMEN

Large-scale, abrupt ecosystem change in direct response to climate extremes is a critical but poorly documented phenomenon1. Yet, recent increases in climate-induced tree mortality raise concern that some forest ecosystems are on the brink of collapse across wide environmental gradients2,3. Here we assessed climatic and productivity trends across the world's five Mediterranean forest ecosystems from 2000 to 2021 and detected a large-scale, abrupt forest browning and productivity decline in Chile (>90% of the forest in <100 days), responding to a sustained, acute drought. The extreme dry and warm conditions in Chile, unprecedented in the recent history of all Mediterranean-type ecosystems, are akin to those projected to arise in the second half of the century4. Long-term recovery of this forest is uncertain given an ongoing decline in regional water balance. This dramatic plummet of forest productivity may be a spyglass to the future for other Mediterranean ecosystems.


Asunto(s)
Cambio Climático , Ecosistema , Bosques , Árboles/fisiología , Sequías
6.
Ecol Appl ; 31(6): e02394, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34164882

RESUMEN

Seedling planting plays a key role in active forest restoration and regeneration of managed stands. Plant attributes at outplanting can determine tree seedling survival and consequently early success of forest plantations. Although many studies show that large seedlings of the same age within a species have higher survival than small ones, others report the opposite. This may be due to differences in environmental conditions at the planting site and in the inherent functional characteristics of species. Here, we conducted a global-scale meta-analysis to evaluate the effect of seedling size on early outplanting survival. Our meta-analysis covered 86 tree species and 142 planting locations distributed worldwide. We also assessed whether planting site aridity and key plant functional traits related to abiotic and biotic stress resistance and growth capacity, namely specific leaf area and wood density, modulate this effect. Planting large seedlings within a species consistently increases survival in forest plantations worldwide. Species' functional traits modulate the magnitude of the positive seedling size-outplanting survival relationship, showing contrasting effects due to aridity and between angiosperms and gymnosperms. For angiosperms planted in arid/semiarid sites and gymnosperms in subhumid/humid sites the magnitude of the positive effect of seedling size on survival was maximized in species with low specific leaf area and high wood density, characteristics linked to high stress resistance and slow growth. By contrast, high specific leaf area and low wood density maximized the positive effect of seedling size on survival for angiosperms planted in subhumid/humid sites. Results have key implications for implementing forest plantations globally, especially for adjusting nursery cultivation to species' functional characteristics and planting site aridity. Nursery cultivation should promote large seedlings, especially for stress sensitive angiosperms planted in humid sites and for stress-resistant species planted in dry sites.


Asunto(s)
Plantones , Clima Tropical , Bosques , Hojas de la Planta , Árboles
7.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33551278

RESUMEN

INTRODUCTION: Immune cell functional assay (ImmuKnow®) is a non-invasive method that measures the state of cellular immunity in immunosuppressed patients. We studied the prognostic value of the assay for predicting non-cytomegalovirus (CMV) infections in lung transplant recipients. METHODS: A multicenter prospective observational study of 92 patients followed up from 6 to 12 months after transplantation was performed. Immune cell functional assay was carried out at 6, 8, 10, and 12 months. RESULTS: Twenty-three patients (25%) developed 29 non-CMV infections between 6 and 12 months post-transplant. At 6 months, the immune response was moderate (ATP 225-525ng/mL) in 14 (15.2%) patients and low (ATP<225ng/mL) in 78 (84.8%); no patients had a strong response (ATP≥525ng/mL). Only 1 of 14 (7.1%) patients with a moderate response developed non-CMV infection in the following 6 months compared with 22 of 78 (28.2%) patients with low response, indicating sensitivity of 95.7%, specificity of 18.8%, positive predictive value (PPV) of 28.2%, and negative predictive value (NPV) of 92.9% (AUC 0.64; p=0.043). Similar acute rejection rates were recorded in patients with mean ATP≥225 vs. <225ng/mL during the study period (7.1% vs. 9.1%, p=0.81). CONCLUSION: Although ImmuKnow® does not seem useful to predict non-CMV infection, it could identify patients with a very low risk and help us define a target for an optimal immunosuppression.

8.
Int J Phytoremediation ; 23(11): 1169-1174, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33594916

RESUMEN

Interest in Baccharis linearis has increased as an alternative for assisted phytostabilization due to its spontaneous colonization of tailings dumps. The search for a novel fast-vegetative propagation technique to accelerate its coverage on mine tailings is a promising research area for sustainable mine closure plans. In this study, we determined the optimal proportion of compost and tailings as growing media to promote fast B. linearis propagation through a compound layering technique. The assessed growing substrates were: 100% tailings, 70% tailings + 30% compost, and 50% tailings + 50% compost. After 84 days of growth, the change in number and height of layering branches, root and shoot dry mass, percentage of ground coverage, and substrate chemical properties were assessed. The main results showed that compound layering of B. linearis is possible with compost addition. The growth of new roots and layering branches was significantly improved by either 30% or 50% compost addition into tailings, due to chemical improvements of substrate (higher nutrients and pH and decreased copper bioavailability). The study confirms that the compound layering of B. linearis may be an effective and novel technique for speeding the reclamation of post-operative mine tailings, which is improved by the incorporation of compost.


Asunto(s)
Baccharis , Compostaje , Contaminantes del Suelo , Biodegradación Ambiental , Cobre , Suelo , Contaminantes del Suelo/análisis
9.
Arch Bronconeumol ; 57(11): 690-696, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35699006

RESUMEN

INTRODUCTION: Immune cell functional assay (ImmuKnow®) is a non-invasive method that measures the state of cellular immunity in immunosuppressed patients. We studied the prognostic value of the assay for predicting non-cytomegalovirus (CMV) infections in lung transplant recipients. METHODS: A multicenter prospective observational study of 92 patients followed up from 6 to 12 months after transplantation was performed. Immune cell functional assay was carried out at 6, 8, 10, and 12 months. RESULTS: Twenty-three patients (25%) developed 29 non-CMV infections between 6 and 12 months post-transplant. At 6 months, the immune response was moderate (ATP 225-525ng/mL) in 14 (15.2%) patients and low (ATP<225ng/mL) in 78 (84.8%); no patients had a strong response (ATP≥525ng/mL). Only 1 of 14 (7.1%) patients with a moderate response developed non-CMV infection in the following 6 months compared with 22 of 78 (28.2%) patients with low response, indicating sensitivity of 95.7%, specificity of 18.8%, positive predictive value (PPV) of 28.2%, and negative predictive value (NPV) of 92.9% (AUC 0.64; p=0.043). Similar acute rejection rates were recorded in patients with mean ATP≥225 vs. <225ng/mL during the study period (7.1% vs. 9.1%, p=0.81). CONCLUSION: Although ImmuKnow® does not seem useful to predict non-CMV infection, it could identify patients with a very low risk and help us define a target for an optimal immunosuppression.


Asunto(s)
Trasplante de Pulmón , Receptores de Trasplantes , Adenosina Trifosfato , Humanos , Huésped Inmunocomprometido , Pulmón
10.
Environ Sci Pollut Res Int ; 24(15): 13484-13496, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28390018

RESUMEN

Abandoned tailing dumps (ATDs) offer an opportunity to identify the main physicochemical filters that determine colonization of vegetation in solid mine wastes. The current study determined the soil physicochemical factors that explain the compositional variation of pioneer vegetal species on ATDs from surrounding areas in semiarid Mediterranean-climate type ecosystems of north-central Chile (Coquimbo Region). Geobotanical surveys-including physicochemical parameters of substrates (0-20 cm depth), plant richness, and coverage of plant species-were performed on 73 ATDs and surrounding areas. A total of 112 plant species were identified from which endemic/native species (67%) were more abundant than exotic species (33%) on ATDs. The distribution of sampling sites and plant species in canonical correspondence analysis (CCA) ordination diagrams indicated a gradual and progressive variation in species composition and abundance from surrounding areas to ATDs because of variations in total Cu concentration (1.3%) and the percentage of soil particles <2 µm (1.8%). According to the CCA, there were 10 plant species with greater abundance on sites with high total Cu concentrations and fine-textured substrates, which could be useful for developing plant-based stabilization programs of ATDs in semiarid Mediterranean-climate type ecosystems of north-central Chile.


Asunto(s)
Contaminantes del Suelo , Suelo/química , Chile , Minería , Plantas
11.
Crit Ultrasound J ; 8(1): 4, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27034059

RESUMEN

BACKGROUND: Medical residents' training in ultrasonography usually follows the recommendations of the American College of Emergency Physicians (ACEP), even though these do not provide specific technical guidelines. Adequate training is considered to require 25 practical iterations in the majority of ultrasound procedures. However, the effectiveness of this approach has not been verified experimentally. We set out to determine the number of repetitions required for an acceptable ultrasound procedure of the inferior vena cava (IVC), as an important and emerging ultrasound procedure in cardiology. METHODS: Using three human models, each of eight medical residents in the Emergency Medicine (EM) Program at the Universidad del Rosario performed 25 iterations of the recommended procedure, with image quality evaluation by an EM physician expert in the technique. Logistic regression analysis was used to determine the lowest number of repetitions required to achieve an adjusted probability of success of 80 and 90 %, respectively. RESULTS: We obtained 200 ultrasound images. The percentage success by each resident ranged from 52 to 96 %. There was no statistical significance in the relation between gender and success (p = 0.83), but there was an association between year of residency and success (p < 0.001). The average time taken for each procedure was 17.3 s (SD 8.1); there was no association between the time taken and either repetition number or image quality. We demonstrate that eleven repetitions are required to achieve acceptable image quality in 80 %, and that 21 repetitions are required to achieve acceptable image quality in 90 %. CONCLUSIONS: This is the first study to formally evaluate the effectiveness of recommended training in ultrasound techniques. Our findings demonstrate that training comprising 25 procedural repetitions is easily sufficient to achieve optimal image quality, and they also provide empiric knowledge toward elucidating the times and minimum repetitions needed to acquire and improve ultrasonographic technique in novice operators to a level which fulfills quality requirements for interpretation.

12.
Rev. chil. cardiol ; 35(1): 25-31, 2016. ilus, tab
Artículo en Español | LILACS | ID: lil-782639

RESUMEN

Antecedentes: En el año 2014 se inició Telemedicina desde el Policlinico de Tratamiento Anticoagulante oral del Hospital San Juan de Dios y el Hospital de Curacaví, evitando así el traslado de pacientes a Santiago para el control con el médico especialista. Métodos: Se utilizó licencia de video conferencia en el Hospital San Juan de Dios, dispositivo móvil, equipo de INR capilar y stock de Acenocumarol en el Hospital de Curacaví. Resultados: En total se han realizado 2.174 consultas vía Telemedicina (junio 2014 a diciembre 2015). Esta estrategia ha sido bien evaluada por los pacientes. La mejora en la calidad del tratamiento ha sido evidente: 58,3% de los pacientes del Hospital de Curacaví se encuentran en rango terapéutico, superior al 50,8% de los pacientes del Hospital San Juan de Dios (p < 0,05). En cuanto al Tiempo en Rango Terapéutico (TTR) 50,6% de los pacientes del Hospital de Curacaví se encuentran en rango versus 46,2% de los pacientes del Hospital San Juan de Dios (p< 0,05). Conclusiones: La Telemedicina utilizada por equipos comprometidos es capaz de mantener indicadores de calidad de la atención que la validan como herramienta de atención clínica a distancia. La Telemedicina, en cuanto es una herramienta que acerca el especialista a comunidades alejadas de centros hospitalarios complejos, es valorada y muy bien calificada por los usuarios.


Background: Starting in 2014 telemedicine has been used to control oral anticoagulant treatment (OAT) in patients attending a peripheral hospital (Curacaví), in connection with Hospital San Juan de Dios, based in Santiago. Methods: A license for video conference was available to communicate both hospitals. Capillary INR and medications were available at Curacaví Hospital. Results: Between June 2014 and December 2015, 2174 indications for OAT have been made through tele-medicine. Different estimates of quality of care and user satisfaction have been rated > 6.7 (1-7 scale). Percent of INR measurements in therapeutic range was 58.3% in Curacavi and 50.8% at Hospital San Juan de Dios (p<0.05) and time in therapeutic range was 50.6% vs 42.6%, respectively (p<0.05) Conclusion: Tele-medicine allowed a close relationship between remote medical facilities and a complex medical center and was fully validated as a means of controlling OAT with a high degree of acceptance by patients.


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Monitoreo de Drogas , Telemedicina/métodos , Anticoagulantes/administración & dosificación , Factores de Tiempo , Capilares , Administración Oral , Encuestas y Cuestionarios , Satisfacción del Paciente , Relación Normalizada Internacional
13.
Asian Cardiovasc Thorac Ann ; 22(3): 371-3, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24585928

RESUMEN

The video-assisted thoracoscopic approach for bronchoplasty procedures is not standardized. Although 3 to 4 incisions are usually made, with adequate surgical technique, the operation can be successfully carried out using only 2 incisions. We describe the technique of video-assisted thoracoscopic surgery for a right upper lobe sleeve lobectomy for a carcinoid tumor in the right upper bronchus, using only 2 ports.


Asunto(s)
Neoplasias de los Bronquios/cirugía , Tumor Carcinoide/cirugía , Neumonectomía/métodos , Cirugía Torácica Asistida por Video , Neoplasias de los Bronquios/patología , Tumor Carcinoide/patología , Femenino , Humanos , Persona de Mediana Edad , Posicionamiento del Paciente , Técnicas de Sutura , Resultado del Tratamiento
15.
Radiol. bras ; Radiol. bras;44(5): 308-314, set.-out. 2011. ilus, graf, tab
Artículo en Portugués | LILACS | ID: lil-612933

RESUMEN

DWI/ADC is a completely non-invasive technique that has been successfully conducted for many years in brain imaging and is currently being studied for the assessment of other organs, such as the abdomen and pelvis and in particular the head and neck structures. Even though DWI and the ADC measurement are able provide tissue information at the cellular level, most imaging centers have not yet adopted them as part of their routine evaluation of the head and neck. DWI has demonstrated usefulness to discriminate specific histological tumor types, especially to differentiate benign solid lesions from malignant masses, to evaluate lymph nodes, particularly to differentiate benign disease from malignancy, to differentiate postradiation changes from residual tumor and potentially to predict therapy success. Moreover DWI seems to be a safer and more affordable method considering the absence of radiation and to the higher cost of FDG-PET to localize tumors and to differentiate benign from malignant masses. Given all these advantages and strengths, DWI will certainly become part of the routine in the MR imaging of the head and neck.


DWI é uma técnica totalmente não invasiva que tem sido utilizada com sucesso por muitos anos em imagens do cérebro e recentemente incluída como parte da avaliação de outros sistemas, por exemplo, no abdome e pelve e na cabeça e pescoço. Apesar de a DWI e a medida dos valores de ADC serem capazes de fornecer informações de tipos histológicos específicos de tumores, a maioria dos centros de imagem ainda não os adotaram como parte da rotina na avaliação da cabeça e pescoço. A medida de ADC demonstrou ser útil para discriminar tipos específicos de tumores histológicos, especialmente para diferenciar lesões benignas sólidas de massas malignas, importante na avaliação de linfonodos cervicais, principalmente para diferenciar processos nodais benignos de malignos, para diferenciar as alterações pós-radioterapia de tumor residual e ter uso potencial para predizer sucesso terapêutico. Além disso, DWI/ADC parece ser um método mais seguro e mais acessível, considerando a ausência de radiação ionizante e ao maior custo do FDG-PET na localização de tumores e diferenciar massas benignas de malignas. Com todas essas vantagens e potencialidades, DWI/ADC certamente fará parte da rotina na avaliação por imagem da cabeça e pescoço.


Asunto(s)
Carcinoma de Células Escamosas , Cabeza , Neoplasias de Cabeza y Cuello , Imagen de Difusión por Resonancia Magnética/métodos , Cuello , Imagen de Difusión por Resonancia Magnética , Sensibilidad y Especificidad
16.
Pediatr Infect Dis J ; 23(10 Suppl): S149-55, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15502694

RESUMEN

AIM: To analyze changes in prevalence and seasonality of diarrhea morbidity and mortality and to evaluate the impact of rotavirus disease among Mexican children younger than 5 years old. METHODS: Diarrhea surveillance was performed from 1990 to 2002. Rotavirus testing was performed on stool specimens from 1996 to 2002. Data were obtained from different surveillance systems considering a nationwide representation in Mexico. Diarrhea morbidity and mortality rates were analyzed against time to determine trends or seasonal patterns. RESULTS: Improvement of surveillance for all diarrhea episodes denoted an initial morbidity increase from 1995 to 1999, followed by a decrease by 2002, without any seasonal pattern. However, from 1990 to 1995, morbidity for severe diarrhea decreased 63%. From 1996 to 2002, 62-68% of severe diarrhea episodes occurring during the fall-winter season (FWS) were rotavirus-positive compared with 6-12% in the spring-summer season (SSS). From 1990 to 2002, diarrhea mortality decreased 84%. Higher mortality rates for children younger than 1 year old coincided precisely during the FWS, annually. Both severe diarrhea episodes and diarrhea deaths denoted a changing seasonal pattern. In 1990-1991, 2 waves of increased diarrhea activity occurred. The increase in SSS was much more pronounced than that in FWS. From 1992 to 1995 for severe diarrhea and from 1993 to 2002 for diarrhea deaths, the SSS frequencies subsequently reduced, whereas the FWS peaks remained annually. CONCLUSIONS: A significant reduction in morbidity and mortality of severe diarrhea has occurred from 1990 and 2002 in Mexican children younger than 5 years old. This is a consequence of preventive programs initiated for cholera control since 1991, which had greater impact on SSS diarrhea and limited response for FWS diarrhea, when rotavirus is mainly present. Currently rotavirus diarrhea requires new prevention strategies and specific control measures, such as a specific national vaccine program.


Asunto(s)
Diarrea/mortalidad , Diarrea/prevención & control , Infecciones por Rotavirus/mortalidad , Infecciones por Rotavirus/prevención & control , Vacunas contra Rotavirus/inmunología , Estaciones del Año , Distribución de Chi-Cuadrado , Preescolar , Diarrea/virología , Femenino , Humanos , Lactante , Recién Nacido , Masculino , México/epidemiología , Vigilancia de la Población , Prevalencia
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