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Start date: 2022Language: search.filters.language.English

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    Item type:Patent,
    METHOD FOR PROCESSING BRAIN IMAGES
    (2022-08-23)
    ZAMORANO MENDIETA, FRANCISCO
    ;
    BILLEKE BOBADILLA, PABLO ERNESTO  
    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
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    Leukocoria in Children: Findings on CT and MRI of the Principal Causes
    (2022)
    N. Sánchez
    ;
    P. Kranz
    ;
    D. Constenla
    <jats:p>Leukocoria is the result of an alteration in the normal red reflex of the ocular fundus, secondary to an obstruction of the normal passage of light to the fundus of the eye that produces a white light reflex. There are many ocular pathologies that can present as leukocoria, among which retinoblastoma is the most frequent. Other causes include cataracts, Coats disease, persistent fetal vasculature, coloboma, retinopathy of prematurity, vitreous hemorrhage, astrocytic hamartoma, and ocular toxocariasis. Although in many situations the diagnosis of these pathologies is clinical or possible with the use of ocular sonography, in certain circumstances, CT or MR imaging may play a very important role in the differential diagnosis. In this review article, we propose that findings such as ocular size, the presence of calcifications, intravenous contrast enhancement, MR imaging signal intensity, CT density, and other pathology-specific findings, along with some clinical data, will guide us to the cause of leukocoria. Knowledge of the most prevalent ages of presentation of these pathologies assists with establishing the final diagnosis.Learning Objectives: To understand why leukocoria occurs, to list the major causes of leukocoria in children, and to recognize the imaging findings of the most frequent causes of leukocoria and apply them in the differential diagnosis</jats:p>
      4
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    Item type:Publication,
    A Chilean Experience of Telestroke in a COVID-19 Pandemic Year
    (2022)
    Carlos Delfino
    ;
    MAZZON AGURTO, ENRICO  
    ;
    Felipe Jurado Díaz
    ;
    MUÑOZ VENTURELLI, PAULA ANDREA  
    ;
    BRUNSER, ALEJANDRO  
    <jats:p>&lt;b&gt;&lt;i&gt;Background and Purpose:&lt;/i&gt;&lt;/b&gt; Telemedicine for stroke patients’ care (telestroke [TS]) has grown notably in recent decades and may offer advantages during health crisis. Hospital admissions related to stroke have decreased globally during the COVID-19 pandemic, but scarce information is available regarding the effect of COVID-19 in TS. Using a population-based TS registry, we investigated the impact of the first year of the COVID-19 pandemic throughout our TS network in Santiago, Chile. &lt;b&gt;&lt;i&gt;Methods:&lt;/i&gt;&lt;/b&gt; Stroke codes evaluated after the onset of COVID-19 restrictions in Chile (defined as March 15, 2020) were compared with those evaluated in 2019. We analyzed differences between number of stroke codes, thrombolysis rate, stroke severity, and time from the stroke onset to hospital admission. &lt;b&gt;&lt;i&gt;Results:&lt;/i&gt;&lt;/b&gt; We observed that the number of stroke codes and the number of patients undergoing reperfusion therapy did not change significantly (&lt;i&gt;p&lt;/i&gt; = 0.669 and 0.415, respectively). No differences were found with respect to the median time from the stroke onset to admission (&lt;i&gt;p&lt;/i&gt; = 0.581) or in National Institutes of Health Stroke Scale (NIHSS) scores (&lt;i&gt;p&lt;/i&gt; = 0.055). The decision-making-to-needle time was significantly shorter in the COVID-19 period (median 5 min [IQR 3–8], &lt;i&gt;p&lt;/i&gt; &amp;#x3c; 0.016), but no significant changes were found at the other times. &lt;b&gt;&lt;i&gt;Conclusions:&lt;/i&gt;&lt;/b&gt; This study demonstrates the potential of adapting TS to extreme situations such as the COVID-19 pandemic, as well as the importance of establishing networks that facilitate patient access to quality treatments. </jats:p>
    Scopus© Citations 7  1
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    Item type:Publication,
    Trail running injury risk factors: a living systematic review
    (2022)
    Carel Viljoen
    ;
    Dina C (Christa) Janse van Rensburg
    ;
    Willem van Mechelen
    ;
    Evert Verhagen
    ;
    Bruno Silva
    <jats:sec><jats:title>Objective</jats:title><jats:p>To review and frequently update the available evidence on injury risk factors and epidemiology of injury in trail running.</jats:p></jats:sec><jats:sec><jats:title>Design</jats:title><jats:p>Living systematic review. Updated searches will be done every 6 months for a minimum period of 5 years.</jats:p></jats:sec><jats:sec><jats:title>Data sources</jats:title><jats:p>Eight electronic databases were searched from inception to 18 March 2021.</jats:p></jats:sec><jats:sec><jats:title>Eligibility criteria</jats:title><jats:p>Studies that investigated injury risk factors and/or reported the epidemiology of injury in trail running.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Nineteen eligible studies were included, of which 10 studies investigated injury risk factors among 2 785 participants. Significant intrinsic factors associated with injury are: more running experience, level A runner and higher total propensity to sports accident questionnaire (PAD-22) score. Previous history of cramping and postrace biomarkers of muscle damage is associated with cramping. Younger age and low skin phototypes are associated with sunburn. Significant extrinsic factors associated with injury are neglecting warm-up, no specialised running plan, training on asphalt, double training sessions per day and physical labour occupations. A slower race finishing time is associated with cramping, while more than 3 hours of training per day, shade as the primary mode of sun protection and being single are associated with sunburn. An injury incidence range 0.7–61.2 injuries/1000 hours of running and prevalence range 1.3% to 90% were reported. The lower limb was the most reported region of injury, specifically involving blisters of the foot/toe.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>Limited studies investigated injury risk factors in trail running. Our review found eight intrinsic and nine extrinsic injury risk factors. This review highlighted areas for future research that may aid in designing injury risk management strategies for safer trail running participation.</jats:p><jats:p>PROSPERO registration number</jats:p><jats:p>CRD42021240832.</jats:p></jats:sec>
      5Scopus© Citations 23
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    Chronic Stress and Ovulatory Dysfunction: Implications in Times of COVID-19
    (2022)
    Pilar Vigil
    ;
    Jaime Meléndez
    ;
    Hugo Soto
    ;
    Grace Petkovic
    ;
    Yanara A. Bernal
    <jats:p>Stress is known to be associated with adverse health outcomes. The COVID-19 pandemic and its associated lockdowns are examples of chronic stressors. Lockdown measures inadvertently caused significant psychological distress and became a powerful source of anxiety/stress, sleep disturbances, nutritional changes and weight gain. Stress is known to impact women's health specifically, through hypothalamic-pituitary-gonadal (HPG) axis dysfunction and resultant ovulatory dysfunction. Such dysfunction may manifest in menstrual irregularities and/or infertility due to hypothalamic hypogonadism. Here, we review the key physiological mediators of stress and associated ovulatory dysfunction. The kisspeptinergic system is comprised of sets of neurons located in the hypothalamus, the rostral periventricular region of the third ventricle (RP3V) and the arcuate nucleus (ARC). This system links nutrition, reproductive signals and stress. It plays a key role in the function of the HPG axis. During chronic stress, the kisspeptinergic system affects the HPG axis, GnRH pulsatility, and, therefore, ovulation. Leptin, insulin and corticotrophin-releasing hormone (CRH) are thought to be additional key modulators in the behavioral responses to chronic stress and may contribute to stress-related ovulatory dysfunction. This mini-review also summarizes and appraises the available evidence on the negative impact of chronic stress as a result of the COVID-19 pandemic lockdowns. It proposes physiological mechanisms to explain the observed effects on women's reproductive health and well-being. The review suggests areas for future research.</jats:p>
    Scopus© Citations 19  1
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    On new Milne-type inequalities and applications
    (2023)
    BOSCH PÉREZ, PAUL JESÚS  
    ;
    José M. Rodríguez
    ;
    José M. Sigarreta
    Inequalities play a major role in pure and applied mathematics. In particular, the inequality plays an important role in the study of Rosseland’s integral for the stellar absorption. In this paper we obtain new Milne-type inequalities, and we apply them to the generalized Riemann–Liouville-type integral operators, which include most of the known Riemann–Liouville integral operators.
      18  1Scopus© Citations 23
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    Unequal Access and Use of Health Care Services among Settled Immigrants, Recent Immigrants, and Locals: A Comparative Analysis of a Nationally Representative Survey in Chile
    (2022)
    Marcela Oyarte
    ;
    CABIESES VALDES, BALTICA BEATRIZ  
    ;
    Isabel Rada
    ;
    Alice Blukacz
    ;
    Manuel Espinoza
    <jats:p>Globally, and particularly in the Latin American region, international migration continues to grow. Access and use of health care services by migrants vary according to their country of origin and residence time. We aimed to compare the access and use of health care services between international migrants (including settled migrants from Peru, Argentina, Bolivia, Ecuador; Emerging migrants from Venezuela, Dominican Republic, Colombia, Haiti; and migrants from other countries) and the Chilean population. After performing a secondary data analysis of population-based nationally representative surveys (CASEN 2011–2017), access and use patterns (insurance, complementary insurance, non-consultation, and non-treatment coverage) were described and compared among settled immigrants, recent emerging immigrants, others, and locals. Immigrants had a significantly higher uninsured population compared to locals. Specifically, in CASEN 2017, 19.27% of emerging (95% CI: 15.3–24.1%), 11.79% of settled (95% CI: 10.1–13.7%), and 2.25% of locals (95% CI: 2.1–2.4%) were uninsured. After 2013, settled and recent emerging migrants showed higher percentages of non-consultation. Collaborative and interculturally relevant strategies from human rights and equity perspectives are needed. Initiatives with a particular focus on recent immigrants can contribute to reducing the existing disparities in health care access and use with locals due to lack of insurance and treatment coverage.</jats:p>
      9Scopus© Citations 10
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    Seroprevalence of Natural and Acquired Immunity against the SARS-CoV-2 Virus in a Population Cohort from Two Chilean Cities, 2020–2022
    (2023)
    Loreto Núñez-Franz
    ;
    Muriel Ramírez-Santana
    ;
    RUBILAR RAMIREZ, PAOLA  
    ;
    Macarena Said
    ;
    VIAL COX, MARIA CECILIA  
    <jats:p>Background: Chile has achieved the highest coverage for vaccines against the SARS-CoV-2 virus worldwide. Objective: To assess the progression of immunity (natural and acquired by vaccine) in a cohort from two Chilean cities. Methods: Individuals (n = 386) who participated in three phases of population-based serial prevalence studies were included (2020–2021 and 2022). Presence of SARS-CoV-2 antibodies was measured in serum. Data including time of vaccination and type of vaccine received were analysed with descriptive statistics. Results: Seroprevalence was 3.6% in the first round and increased to 96.9% in the second and 98.7% in the third. In the third round, 75% of individuals who had received the basal full scheme were seropositive at 180 days or more since their last dose; 98% of individuals who received one booster dose were seropositive at 180 days or more, and 100% participants who received two boosters were seropositive, regardless of time since their last dose. Participants receiving mRNA vaccines had higher seroprevalence rates over time. Conclusions: The high vaccination coverage in Chile enabled the population to maintain high levels of antibodies. Vaccination boosters are essential to maintain immunity over time, which also depends on the type of vaccine administered.</jats:p>
      1Scopus© Citations 12
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    Item type:Publication,
    Multisite Detection of Tn
    <i>1549</i>
    -Mediated
    <i>vanB</i>
    Vancomycin Resistance in Multidrug-Resistant Enterococcus faecalis ST6 in Texas and Florida
    (2023)
    Shelby R. Simar
    ;
    Truc T. Tran
    ;
    Kirsten B. Rydell
    ;
    Diana Panesso
    ;
    German A. Contreras
    <jats:p> In the United States, <jats:italic>vanB</jats:italic> -mediated resistance in enterococci is rare. We characterized three sequence type (ST) 6, vancomycin-resistant <jats:named-content content-type="genus-species">Enterococcus faecalis</jats:named-content> isolates causing bacteremia in unique patients in spatiotemporally distinct settings. </jats:p>
      7  1Scopus© Citations 3
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    Los inicios de la enseñanza de pediatría en Chile y la fundación de hospitales de niños
    (2023)
    Luisa Schonhaut Berman
    ;
    Pablo Chavez Zuñiga
    ;
    Nelson Vargas Catalán
    <jats:p>El objetivo del presente manuscrito es revisar antecedentes históricos previos a la creación de la Sociedad Chilena de Pediatría (SOCHIPE) en el año 1922, con el propósito de reflexionar sobre su impacto en la profesionalización de la pediatría nacional, especialmente en la salud y sobrevida de los niños. Se revisaron documentos de la Junta de Beneficencia, libros y estudios especializados de la época. Hasta principios del siglo XX, el país ostentaba una de las tasas de mortalidad infantil más elevadas del mundo, y contaba con precarias instalaciones para enfrentarlas. En aquellos años, el único establecimiento cerrado para la atención de infantes era la Casa de Huérfanos, que estaba al cuidado de religiosas con apoyo de médicos; es ahí donde se desarrollaron los primeros cursos teórico-prácticos de la especialidad. Presionados por la alta mortalidad infantil y las mortíferas epidemias, la Junta de Beneficencia vio la urgencia de mejorar las condiciones higiénicas y crear instalaciones para el cuidado de los niños. El manuscrito aborda el surgimiento de espacios encargados del resguardo de la salud de los menores de cinco años, desde la creación de la cátedra de pediatría y del primer hospital de niños, el Hospital Roberto del Río, lo que marcó el inicio de las políticas de salud pública infantiles.</jats:p>
      4Scopus© Citations 3