CRIS

Permanent URI for this communityhttps://investigadores.udd.cl/handle/123456789/1

Browse

Search Results

Now showing 1 - 10 of 99
  • Some of the metrics are blocked by your 
    Item type:Patent,
    METHOD FOR PROCESSING BRAIN IMAGES
    (2022-08-23)
    ZAMORANO MENDIETA, FRANCISCO
    ;
    The present invention relates to a novel methodology for the field of brain images from Positron Emission Tomography (PET), likewise applicable to brain images from Single-Photon Emission Computer Tomography (SPECT) or another technique that makes it possible to generate images of brain metabolism, function or blood flow. This methodology arises from the need to improve the medical diagnosis of neurological disorders and from the need for objective, unbiased quantification of brain metabolism. The method is based on the spatial symmetry of the metabolism of the healthy human brain. Under this assumption, the entire healthy brain metabolism can be deduced from the metabolism of a single hemisphere of the brain.
      14
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Polypoid melanoma: An aggressive variant of nodular melanoma
    (2018)
    Pérez-Wilson, Jaime
    ;
    Arellano, Javier
    ;
    Genetic evidence for a trimeric structure for purine nucleoside phosphorylase in the brook lamprey is presented. This enzyme is encoded by a single locus with two alleles segregating at frequencies of 0.98 and 0.02 in a Welsh population. It is suggested that this enzyme is likely to be a trimer in all classes of vertebrates.
      1Scopus© Citations 2  4
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Cardiovascular Assessment Tool for Breast Cancer Survivors and Oncology Providers: Usability Study
    (2021)
    Kathryn E Weaver
    ;
    Heidi D Klepin
    ;
    Brian J Wells
    ;
    Emily V Dressler
    ;
    Karen M Winkfield
    <jats:sec> <jats:title>Background</jats:title> <jats:p>Cardiovascular health is of increasing concern to breast cancer survivors and their health care providers, as many survivors are more likely to die from cardiovascular disease than cancer. Implementing clinical decision support tools to address cardiovascular risk factor awareness in the oncology setting may enhance survivors’ attainment or maintenance of cardiovascular health.</jats:p> </jats:sec> <jats:sec> <jats:title>Objective</jats:title> <jats:p>We sought to evaluate survivors’ awareness of cardiovascular risk factors and examine the usability of a novel electronic health record enabled cardiovascular health tool from the perspective of both breast cancer survivors and oncology providers.</jats:p> </jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>Breast cancer survivors (n=49) recruited from a survivorship clinic interacted with the cardiovascular health tool and completed pre and posttool assessments about cardiovascular health knowledge and perceptions of the tool. Oncologists, physician assistants, and nurse practitioners (n=20) who provide care to survivors also viewed the cardiovascular health tool and completed assessments of perceived usability and acceptability.</jats:p> </jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>Enrolled breast cancer survivors (84% White race, 4% Hispanic ethnicity) had been diagnosed 10.8 years ago (SD 6.0) with American Joint Committee on Cancer stage 0, I, or II (45/49, 92%). Prior to viewing the tool, 65% of survivors (32/49) reported not knowing their level for one or more cardiovascular health factors (range 0-4). On average, only 45% (range 0%-86%) of survivors’ known cardiovascular health factors were at an ideal level. More than 50% of survivors had ideal smoking status (45/48, 94%) or blood glucose level (29/45, 64%); meanwhile, less than 50% had ideal blood pressure (12/49, 24%), body mass index (12/49, 24%), cholesterol level (17/35, 49%), diet (7/49, 14%), and physical activity (10/49. 20%). More than 90% of survivors thought the tool was easy to understand (46/47, 98%), improved their understanding (43/47, 91%), and was helpful (45/47, 96%); overall, 94% (44/47 survivors) liked the tool. A majority of survivors (44/47, 94%) thought oncologists should discuss cardiovascular health during survivorship care. Most (12/20, 60%) oncology providers (female: 12/20, 60%; physicians: 14/20, 70%) had been practicing for more than 5 years. Most providers agreed the tool provided useful information (18/20, 90%), would help their effectiveness (18/20, 90%), was easy to use (20/20, 100%), and presented information in a useful format (19/20, 95%); and 85% of providers (17/20) reported they would use the tool most or all of the time when providing survivorship care.</jats:p> </jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>These usability data demonstrate acceptability of a cardiovascular health clinical decision support tool in oncology practices. Oncology providers and breast cancer survivors would likely value the integration of such apps in survivorship care. By increasing awareness and communication regarding cardiovascular health, electronic health record–enabled tools may improve survivorship care delivery for breast cancer and ultimately patient outcomes.</jats:p> </jats:sec>
      10Scopus© Citations 10
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Ecocardiografía Funcional y sus aplicaciones clínicas en Neonatología
    (2021)
    Irene Montoya Claramunt
    ;
    Claudia Sánchez Ramírez
    ;
    Raul Nachar Hidalgo
    ;
    Jorge Torres Torretti
    <jats:p>La Ecocardiografía funcional surge como una herramienta clínica para la valoración del estado hemodinámico del paciente, luego de demostrarse que los métodos clínicos usados tradicionalmente en la unidad de cuidados intensivos neonatales son limitados y muchas veces tardíos. Esto nos permite establecer un diagnóstico hemodinámico más certero y así mejorar la morbimortalidad neonatal ya que permite formular una recomendación basada en la fisiología, que resulta en un plan de tratamiento racional e individualizado. Los escenarios en los cuales se ha visto su utilidad son: transición inadecuada del recién nacido prematuro de muy bajo peso de nacimiento, inestabilidad hemodinámica, valoración del ductus arterioso persitente y su repercusión hemodinámica e hipertensión pulmonar. La presente revisión actualiza la información sobre la utilidad de la ecocardiografía funcional en la unidad de cuidados intensivos neonatales y los escenarios clínicos en donde se recomienda su uso.</jats:p>
      1Scopus© Citations 4
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Novel Pannexin-1-Coupled Signaling Cascade Involved in the Control of Endothelial Cell Function and NO-Dependent Relaxation
    (2021)
    Mauricio A. Lillo
    ;
    Pablo S. Gaete
    ;
    Mariela Puebla
    ;
    Pía C. Burboa
    ;
    Inés Poblete
    <jats:p>Deletion of pannexin-1 (Panx-1) leads not only to a reduction in endothelium-derived hyperpolarization but also to an increase in NO-mediated vasodilation. Therefore, we evaluated the participation of Panx-1-formed channels in the control of membrane potential and [Ca2+]i of endothelial cells. Changes in NO-mediated vasodilation, membrane potential, superoxide anion (O2⋅–) formation, and endothelial cell [Ca2+]i were analyzed in rat isolated mesenteric arterial beds and primary cultures of mesenteric endothelial cells. Inhibition of Panx-1 channels with probenecid (1 mM) or the Panx-1 blocking peptide 10Panx (60 μM) evoked an increase in the ACh (100 nM)-induced vasodilation of KCl-contracted mesenteries and in the phosphorylation level of endothelial NO synthase (eNOS) at serine 1177 (P-eNOSS1177) and Akt at serine 473 (P-AktS473). In addition, probenecid or 10Panx application activated a rapid, tetrodotoxin (TTX, 300 nM)-sensitive, membrane potential depolarization and [Ca2+]i increase in endothelial cells. Interestingly, the endothelial cell depolarization was converted into a transient spike after removing Ca2+ ions from the buffer solution and in the presence of 100 μM mibefradil or 10 μM Ni2+. As expected, Ni2+ also abolished the increment in [Ca2+]i. Expression of Nav1.2, Nav1.6, and Cav3.2 isoforms of voltage-dependent Na+ and Ca2+ channels was confirmed by immunocytochemistry. Furthermore, the Panx-1 channel blockade was associated with an increase in O2⋅– production. Treatment with 10 μM TEMPOL or 100 μM apocynin prevented the increase in O2⋅– formation, ACh-induced vasodilation, P-eNOSS1177, and P-AktS473 observed in response to Panx-1 inhibition. These findings indicate that the Panx-1 channel blockade triggers a novel complex signaling pathway initiated by the sequential activation of TTX-sensitive Nav channels and Cav3.2 channels, leading to an increase in NO-mediated vasodilation through a NADPH oxidase-dependent P-eNOSS1177, which suggests that Panx-1 may be involved in the endothelium-dependent control of arterial blood pressure.</jats:p>
      7Scopus© Citations 13
  • Some of the metrics are blocked by your 
    Item type:Publication,
    An integrated multi-criteria decision analysis and optimization modeling approach to spatially operational road repair decisions
    (2021)
    Sättar Ezzati
    ;
    ;
    Pete Bettinger
    ;
    Ljusk Ola Eriksson
    ;
    Anjali Awasthi
    In this study, we developed a generic cost-effective approach for spatially explicit decision support involving the allocation of road repair treatments. The approach begins with an assessment of the existing road condition to identify the extent of environmental impacts and to determine road repair regimes in a subjective manner using group-decision making efforts. An integer programming model is then formulated by combining expert opinions with operational costs to guide repair schedules required for each road segment at the operational planning level. To demonstrate model performance, we applied it to a 400 km<jats:sup>2</jats:sup> landscape consisting of 289 km of paved roads in the mountainous region of the Hyrcanian forests in Iran. We assessed sensitivity of the inputs, such as weight verification, budgetary limitations, and rehabilitation weights. The results of the subjective analysis show that 76% of the roads analyzed in these forests must be prioritized to receive treatments as intended for logistical purposes. Incorporating the extent of environmental dimensions into operational costs allows us to generate an optimal tradeoff curve by selecting an appropriate treatment for segments of a road network. The approach demonstrated here can be used to design detailed alternative solutions for addressing spatially-informed road decisions under various terrain conditions.
      4Scopus© Citations 5
  • Some of the metrics are blocked by your 
    Item type:Publication,
    The dual aversion of Chile’s constitution-making process
    <jats:title>Abstract</jats:title> <jats:p>Chile initiated a constitution-making process in late 2019, after the major political parties signed an agreement to respond to the massive demonstrations that took over the streets in October of 2019. Dominant trends in Chile and Latin America’s constitutional thought typically examine this type of process through the lenses of the constituent power or transformative constitutionalism. The authors of this essay offer a different view. They argue that Chile’s constitution-making process, as designed by the multiparty agreement, manifests a double aversion: to avoid the Bolivarian way of constitution-making—including its associated constituent power narrative—and to put an end to the institutional and symbolic legacy of the Pinochet regime. In attempting to stay clear of these two negative models, the authors argue that the rules of the constitution-making process have adopted the main features of the post-sovereign model of constitution-making.</jats:p>
      14Scopus© Citations 19
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Parámetros hematológicos y biomarcadores predictores de gravedad en Síndrome Inflamatorio Pediátrico Multisistémico asociado a SARS-CoV-2
    (2021)
    Patricia Verdugo
    ;
    Patricia Álvarez
    ;
    Patricia Aroca
    ;
    Vicente Enrique Montes-nogales
    ;
    <jats:p>El síndrome inflamatorio multisistémico pediátrico asociado a SARS-CoV-2 (MIS-C) se caracteriza por un estado hiperinflamatorio producto de una tormenta de citoquinas, evidenciado en alteraciones del laboratorio hematológico y proteínas de fase aguda.Objetivo: Describir las características clínicas y de laboratorio de pacientes hospitalizados por MIS-C e identificar marcadores predictores de gravedad.Pacientes y Método: Estudio retrospectivo de 32 pacientes. El grupo se dividió en crítico y no crítico según presentación clínica y tipo de terapia utilizada. En ellos se estudiaron aspectos clínicos y de laboratorio que incluyeron hemograma completo, pruebas de coagulación y biomarcadores. Resultados: 18/32 hombres, mediana de edad 6,8 años. Las manifestaciones más frecuentes fueron cardiovasculares (84,3%), digestivas (84%) y mucocutáneas (59%). El grupo de los críticos incluyó 15 pacientes, 12 hombres con mediana de edad de 8,9 años y los no críticos 17 pacientes; 6 hombres, con mediana de edad de 5,4 años. Los parámetros de laboratorio al ingreso en el grupo global mostraron aumento de la proteína C reactiva, dímero-D, leucocitos, neutrófilos, ferritina y fibrinógeno. La albúmina y la natremia en cambio se encontraban disminuidas. El grupo crítico se caracterizó por tener al ingreso: trombocitopenia, hipoalbuminemia, prolongación del tiempo de protrombina y elevación de la ferritina. Al deterioro hubo acentuación de la trombocitopenia, ascenso mayor de la proteína C reactiva junto a elevación de los neutrófilos.Conclusión: El hemograma, la proteína C reactiva y la albuminemia al ingreso resultaron ser de alto valor en la identificación de pacientes con riesgo de agravamiento clínico.</jats:p>
      20Scopus© Citations 10
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Lesions that do or do not impair digit span: a study of 816 stroke survivors
    (2021)
    Sharon Geva
    ;
    Teodros Truneh
    ;
    Mohamed L Seghier
    ;
    Thomas M H Hope
    ;
    Alex P Leff
    <jats:title>Abstract</jats:title> <jats:p>Prior studies have reported inconsistency in the lesion sites associated with verbal short-term memory impairments. Here we asked: How many different lesion sites can account for selective impairments in verbal short-term memory that persist over time, and how consistently do these lesion sites impair verbal short-term memory? We assessed verbal short-term memory impairments using a forward digit span task from the Comprehensive Aphasia Test. First, we identified the incidence of digit span impairments in a sample of 816 stroke survivors (541 males/275 females; age at stroke onset 56 ± 13 years; time post-stroke 4.4 ± 5.2 years). Second, we studied the lesion sites in a subgroup of these patients (n = 39) with left hemisphere damage and selective digit span impairment—defined as impaired digit span with unimpaired spoken picture naming and spoken word comprehension (tests of speech production and speech perception, respectively). Third, we examined how often these lesion sites were observed in patients who either had no digit span impairments or digit span impairments that co-occurred with difficulties in speech perception and/or production tasks. Digit span impairments were observed in 222/816 patients. Almost all (199/222 = 90%) had left hemisphere damage to five small regions in basal ganglia and/or temporo-parietal areas. Even complete damage to one or more of these five regions was not consistently associated with persistent digit span impairment. However, when the same regions were spared, only 5% (23/455) presented with digit span impairments. These data suggest that verbal short-term memory impairments are most consistently associated with damage to left temporo-parietal and basal ganglia structures. Sparing of these regions very rarely results in persistently poor verbal short-term memory. These findings have clinical implications for predicting recovery of verbal short-term memory after stroke.</jats:p>
      1Scopus© Citations 14  2
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Global research priorities for COVID-19 in maternal, reproductive and child health: Results of an international survey
    (2021)
    Melanie Etti
    ;
    Jackeline Alger
    ;
    Sofía P. Salas
    ;
    Robin Saggers
    ;
    Tanusha Ramdin
    <jats:sec id="sec001"> <jats:title>Background</jats:title> <jats:p>The World Health Organization’s “<jats:italic>Coordinated Global Research Roadmap</jats:italic>: <jats:italic>2019 Novel Coronavirus</jats:italic>” outlined the need for research that focuses on the impact of COVID-19 on pregnant women and children. More than one year after the first reported case significant knowledge gaps remain, highlighting the need for a coordinated approach. To address this need, the Maternal, Newborn and Child Health Working Group (MNCH WG) of the COVID-19 Clinical Research Coalition conducted an international survey to identify global research priorities for COVID-19 in maternal, reproductive and child health.</jats:p> </jats:sec> <jats:sec id="sec002"> <jats:title>Method</jats:title> <jats:p>This project was undertaken using a modified Delphi method. An electronic questionnaire was disseminated to clinicians and researchers in three different languages (English, French and Spanish) via MNCH WG affiliated networks. Respondents were asked to select the five most urgent research priorities among a list of 17 identified by the MNCH WG. Analysis of questionnaire data was undertaken to identify key similarities and differences among respondents according to questionnaire language, location and specialty. Following elimination of the seven lowest ranking priorities, the questionnaire was recirculated to the original pool of respondents. Thematic analysis of final questionnaire data was undertaken by the MNCH WG from which four priority research themes emerged.</jats:p> </jats:sec> <jats:sec id="sec003"> <jats:title>Results</jats:title> <jats:p>Questionnaire 1 was completed by 225 respondents from 29 countries. Questionnaire 2 was returned by 49 respondents. The four priority research themes which emerged from the analysis were 1) access to healthcare during the COVID-19 pandemic, 2) the direct and 3) indirect effects of COVID-19 on pregnant and breastfeeding women and children and 4) the transmission of COVID-19 and protection from infection.</jats:p> </jats:sec> <jats:sec id="sec004"> <jats:title>Conclusion</jats:title> <jats:p>The results of these questionnaires indicated a high level of concordance among continents and specialties regarding priority research themes. This prioritized list of research uncertainties, developed to specifically highlight the most urgent clinical needs as perceived by healthcare professionals and researchers, could help funding organizations and researchers to answer the most pressing questions for clinicians and public health professionals during the pandemic. It is hoped that these identified priority research themes can help focus the discussion regarding the allocation of limited resources to enhance COVID-19 research in MNCH globally.</jats:p> </jats:sec>
      3Scopus© Citations 8