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1.
Proc Natl Acad Sci U S A ; 117(52): 33373-33383, 2020 12 29.
Article in English | MEDLINE | ID: mdl-33318178

ABSTRACT

Natural selection is an important driver of genetic and phenotypic differentiation between species. For species in which potential gene flow is high but realized gene flow is low, adaptation via natural selection may be a particularly important force maintaining species. For a recent radiation of New World desert shrubs (Encelia: Asteraceae), we use fine-scale geographic sampling and population genomics to determine patterns of gene flow across two hybrid zones formed between two independent pairs of species with parapatric distributions. After finding evidence for extremely strong selection at both hybrid zones, we use a combination of field experiments, high-resolution imaging, and physiological measurements to determine the ecological basis for selection at one of the hybrid zones. Our results identify multiple ecological mechanisms of selection (drought, salinity, herbivory, and burial) that together are sufficient to maintain species boundaries despite high rates of hybridization. Given that multiple pairs of Encelia species hybridize at ecologically divergent parapatric boundaries, such mechanisms may maintain species boundaries throughout Encelia.


Subject(s)
Asteraceae/genetics , Desert Climate , Hybridization, Genetic , Selection, Genetic , Ecosystem , Gene Flow , Genetic Fitness , Herbivory , Mexico , Salinity , Water , Wind
2.
Acta méd. costarric ; 61(1)ene.-mar. 2019.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1505470

ABSTRACT

La colonoscopia se considera como la prueba de elección para el tamizaje del cáncer colorrectal. Su eficacia dependerá de múltiples factores entre los que se incluyen una preparación adecuada, una inspección meticulosa al realizar la exploración, apego a las recomendaciones de seguimiento y una capacitación óptima del colonoscopista. Para asegurar que los endoscopistas a nivel nacional brinden una colonoscopia de calidad, surge la iniciativa de establecer indicadores de calidad locales. A continuación, la Asociación Costarricense de Gastroenterología y Endoscopia Digestiva propone los indicadores de calidad para la realización de colonoscopias seguras y efectivas.


Colonoscopy is considered as the gold standard study for colorectal cancer. The efficacy of colonoscopy depends on multiple factors, including a correct bowel preparation, careful inspection tecnique, close following of the screening guidelines and adecuate training of the colonoscopist. The initiative of establishing local quality indicatorsarise from the necessity to arise the quality of the colonospy delivered by Costarican endoscopists. On this document, the Costarican Society of Gastroenterology and Digestive Endoscopy establishes quality indicators for performing safe and effective colonoscopy.

3.
Adv Wound Care (New Rochelle) ; 7(4): 134-143, 2018 Apr 01.
Article in English | MEDLINE | ID: mdl-29675338

ABSTRACT

Objective: Venous leg ulcers (VLUs) are one of the most common complications in lower extremity wounds. To date, clinicians employ visual inspection of the wound site during its healing process by monitoring surface granulation and reduction in wound size across weeks of treatment. In this study, a handheld near-infrared optical scanner (NIROS) has been developed at the Optical Imaging Laboratory to differentiate healing from nonhealing VLUs based on differences in blood flow to the wound and its surroundings. Approach: Noncontact near-infrared (NIR) area imaging of 12 VLUs have been carried out at two podiatric clinics. Diffuse reflectance images of the wounds were used to quantify optical contrasts between the wound and its surroundings. The variability in imaging conditions, analysis, and operator dependency were assessed to determine the robustness of the imaging approach. Results: Optical contrast obtained from diffuse reflectance images of VLUs were distinctly different for healing (positive contrast) and nonhealing (negative contrast) wounds, independent of the varying imaging and data analysis conditions. Innovation: NIR imaging of wounds to differentiate healing from nonhealing VLUs using a noncontact wide-area imager has been demonstrated for the first time. Conclusion: The application of a portable handheld imager to assess the healing or nonhealing nature of VLUs during weekly clinical treatment is significant since physiological changes, as observed using NIROS, manifest before visual reduction in wound size during the healing process.

4.
Adv Wound Care (New Rochelle) ; 5(8): 349-359, 2016 Aug 01.
Article in English | MEDLINE | ID: mdl-27602254

ABSTRACT

Significance: Noninvasive imaging approaches can provide greater information about a wound than visual inspection during the wound healing and treatment process. This review article focuses on various optical imaging techniques developed to image different wound types (more specifically ulcers). Recent Advances: The noninvasive optical imaging approaches in this review include hyperspectral imaging, multispectral imaging, near-infrared spectroscopy (NIRS), diffuse reflectance spectroscopy, optical coherence tomography, laser Doppler imaging, laser speckle imaging, spatial frequency domain imaging, and fluorescence imaging. The various wounds imaged using these techniques include open wounds, chronic wounds, diabetic foot ulcers, decubitus ulcers, venous leg ulcers, and burns. Preliminary work in the development and implementation of a near-infrared optical scanner for wound imaging as a noncontact hand-held device is briefly described. The technology is based on NIRS and has demonstrated its potential to differentiate a healing from nonhealing wound region. Critical Issues: While most of the optical imaging techniques can penetrate few hundred microns to a 1-2 mm from the wound surface, NIRS has the potential to penetrate deeper, demonstrating the potential to image internal wounds. Future Directions: All the technologies are currently at various stages of translational efforts to the clinic, with NIRS holding a greater promise for physiological assessment of the wounds internal, beyond the gold-standard visual assessment.

5.
Rev. enferm. neurol ; 15(1): 10-18, ene-abr 2016.
Article in Spanish | LILACS, BDENF - Nursing | ID: biblio-1024333

ABSTRACT

Las posturas que identifican las causas de un efecto adverso (EA) han sido vistas únicamente desde una perspectiva cuantitativa, con fines de determinar la incidencia, evitabilidad y factores de riesgo, lo que resulta complicado por la subjetividad del fenómeno.


Subject(s)
Humans , Nursing , Pharmaceutical Preparations , No-Observed-Adverse-Effect Level
6.
Neurosci Lett ; 492(2): 99-104, 2011 Apr 01.
Article in English | MEDLINE | ID: mdl-21291957

ABSTRACT

Previous studies have investigated whether routine use of antiepileptic drugs is adequate to improve cognitive abilities in children who are learning disabled not otherwise specified (LD NOS) and who display interictal paroxysmal patterns in the electroencephalogram (EEG) but do not have epilepsy, and the findings of these studies have been controversial. In the current study, 112 LD children without epilepsy were assessed; however, only 18 met the strict inclusion/exclusion criteria in order to obtain a homogeneous sample. These children showed interictal paroxysmal patterns in the EEG, and a randomized, double-blind trial was carried out on them. The children were treated with either magnesium valproate (MgV; 20mg/kg/day) or a placebo for six months, and differences in WISC subtests, in a computerized reading skills battery (BTL) and EEG recordings were evaluated between groups before and after the treatment period. Performance IQ score and several items of the BTL (rhymes and ordering of words) improved in children who received MgV, whereas no changes were observed in the placebo group. No changes in the number of interictal paroxysmal patterns were observed in any group; however increased EEG currents at 10.92 and 12.87Hz (alpha band) in posterior regions and decreased currents in frequencies within the theta band (3.90, 4.29 and 5.07Hz) in frontal regions and at 4.68 and 5.46Hz in the parietal cortex were observed, suggesting an improvement in EEG maturation.


Subject(s)
Brain Mapping , Enzyme Inhibitors/therapeutic use , Learning Disabilities/drug therapy , Learning Disabilities/physiopathology , Valproic Acid/therapeutic use , Child , Electroencephalography/methods , Enzyme Inhibitors/pharmacology , Female , Humans , Male , Neuropsychological Tests , Photic Stimulation , Psychophysics , Valproic Acid/pharmacology
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