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1.
Alzheimers Dement ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38963127

ABSTRACT

INTRODUCTION: This study derived composite scores for two novel cognitive measures, the No Practice Effect (NPE) battery and the Miami Computerized Functional Skills Assessment and Training system for use in early-stage Alzheimer's disease (AD) clinical trials. Their psychometric properties and associations with AD risk markers were compared to those of well-established measures. METHODS: For 291 older adults with healthy cognition or early mild cognitive impairment, Exploratory factor analyses were used to identify the factor structure of the NPE. Factor and total scores were examined for their psychometric properties and associations with AD risk biomarkers. RESULTS: Composite scores from the novel cognitive and functional measures demonstrated better psychometric properties (distribution and test-retest reliability) and stronger associations with AD-related demographic, genetic, and brain risk markers than well-established measures, DISCUSSION: These novel measures have potential for use as primary cognitive and functional outcomes in early-stage AD clinical trials. HIGHLIGHTS: Well-established cognitive tests may not accurately detect subtle cognitive changes. No Practice Effect (NPE) and Computerized Functional Skills Assessment and Training are novel measures designed to have improved psychometric properties. NPE had Executive Function, Cognitive Control/Speed, and Episodic Memory domains. Novel measures had better psychometric properties compared to established measures. Significant associations with Alzheimer's disease biomarkers were found with novel measures.

2.
Entropy (Basel) ; 26(2)2024 Jan 29.
Article in English | MEDLINE | ID: mdl-38392373

ABSTRACT

The Non-Informative Nuisance Parameter Principle concerns the problem of how inferences about a parameter of interest should be made in the presence of nuisance parameters. The principle is examined in the context of the hypothesis testing problem. We prove that the mixed test obeys the principle for discrete sample spaces. We also show how adherence of the mixed test to the principle can make performance of the test much easier. These findings are illustrated with new solutions to well-known problems of testing hypotheses for count data.

3.
Front Bioeng Biotechnol ; 11: 1257778, 2023.
Article in English | MEDLINE | ID: mdl-37799814

ABSTRACT

Introduction: Thrombogenesis, a major cause of implantable cardiovascular device failure, can be addressed through the use of biodegradable polymers modified with anticoagulating moieties. This study introduces a novel polyester urethane urea (PEUU) functionalized with various anti-platelet deposition molecules for enhanced antiplatelet performance in regenerative cardiovascular devices. Methods: PEUU, synthesized from poly-caprolactone, 1,4-diisocyanatobutane, and putrescine, was chemically oxidized to introduce carboxyl groups, creating PEUU-COOH. This polymer was functionalized in situ with polyethyleneimine, 4-arm polyethylene glycol, seleno-L-cystine, heparin sodium, and fondaparinux. Functionalization was confirmed using Fourier-transformed infrared spectroscopy and X-ray photoelectron spectroscopy. Bio-compatibility and hemocompatibility were validated through metabolic activity and hemolysis assays. The anti-thrombotic activity was assessed using platelet aggregation, lactate dehydrogenase activation assays, and scanning electron microscopy surface imaging. The whole-blood clotting time quantification assay was employed to evaluate anticoagulation properties. Results: Results demonstrated high biocompatibility and hemocompatibility, with the most potent anti-thrombotic activity observed on pegylated surfaces. However, seleno-L-cystine and fondaparinux exhibited no anti-platelet activity. Discussion: The findings highlight the importance of balancing various factors and addressing challenges associated with different approaches when developing innovative surface modifications for cardiovascular devices.

4.
Adv Virus Res ; 117: 81-119, 2023.
Article in English | MEDLINE | ID: mdl-37832992

ABSTRACT

Astroviruses encapsidate a positive-sense, single-stranded RNA genome into ∼30nm icosahedral particles that infect a wide range of mammalian and avian species, but their biology is not well understood. Human astroviruses (HAstV) are divided into three clades: classical HAstV serotypes 1-8, and novel or non-classical HAstV of the MLB and VA clades. These viruses are part of two genogroups and phylogenetically cluster with other mammalian astroviruses, highlighting their zoonotic potential. HAstV are a highly prevalent cause of nonbacterial gastroenteritis, primarily in children, the elderly and immunocompromised. Additionally, asymptomatic infections and extraintestinal disease (e.g., encephalitis), are also observed, mostly in immunocompetent or immunocompromised individuals, respectively. While these viruses are highly prevalent, no approved vaccines or antivirals are available to prevent or treat infections. This is in large part due to their understudied nature and the limited understanding of even very basic features of their life cycle and pathogenesis at the cellular and organismal level. This review will summarize molecular features of human astrovirus biology, pathogenesis, and tropism, and then focus on two stages of the viral life cycle, namely entry and egress, since these are proven targets for therapeutic interventions. We will further highlight gaps in knowledge in hopes of stimulating future research into these understudied viruses.


Subject(s)
Gastroenteritis , Mamastrovirus , Animals , Child , Humans , Aged , Mamastrovirus/genetics , Genotype , Phylogeny , Mammals
5.
Antibiotics (Basel) ; 12(7)2023 Jun 22.
Article in English | MEDLINE | ID: mdl-37508183

ABSTRACT

The Caribbean region is a hotspot of biodiversity (i.e., algae, sponges, corals, mollusks, microorganisms, cyanobacteria, and dinoflagellates) that produces secondary metabolites such as polyketides and polypropionates. Polyketides are a diverse class of natural products synthesized by organisms through a biosynthetic pathway catalyzed by polyketide synthase (PKS). This group of compounds is subdivided into fatty acids, aromatics, and polypropionates such as macrolides, and linear and cyclic polyethers. Researchers have studied the Caribbean region to find natural products and focused on isolation, purification, structural characterization, synthesis, and conducting biological assays against parasites, cancer, fungi, and bacteria. These studies have been summarized in this review, including research from 1981 to 2020. This review includes about 90 compounds isolated in the Caribbean that meet the structural properties of polyketides. Out of 90 compounds presented, 73 have the absolute stereochemical configuration, and 82 have shown biological activity. We expect to motivate the researchers to continue exploring the Caribbean region's marine environments to discover and investigate new polyketide and polypropionate natural products.

6.
Int J Ophthalmol ; 16(3): 434-441, 2023.
Article in English | MEDLINE | ID: mdl-36935800

ABSTRACT

AIM: To determine the prevalence of refractive error in 5- to 17-year-old schoolchildren in Puerto Rico. METHODS: A quantitative descriptive study of 2867 children aged 5 to 17y from all seven educational regions of Puerto Rico was conducted from 2016-2019. Refractive error was determined via static and subjective refraction. Children with distance acuity ≤20/40 or near visual acuity ≤20/32 had a cycloplegic refraction. Data analysis included descriptive statistics, correlation coefficient, Kruskal-Wallis, Chi-square, and t test calculations. RESULTS: Twenty percent of the children had a spherical equivalent refractive error ≤ -0.50 D, 3.2% had a spherical equivalent ≥ +2.00 D, and 10.4% had astigmatism ≥1 D. There was a statistically (but non-clinically) significant myopic change in spherical equivalent refractive error with age (P<0.001). The prevalence of myopia increased with age (P<0.001) but not hyperopia (P=0.59) or astigmatism (P=0.51). Males had a significantly higher hyperopic spherical equivalent than females (P<0.001). Females had a higher prevalence of myopia (P<0.001) than males, but there was no difference in the hyperopia (P=0.74) or astigmatism prevalence (P=0.87). CONCLUSION: The prevalence of a spherical equivalent equal to or less than -0.50 D (myopia, 20.7%) is one of the highest among similar-aged children worldwide. Further studies should explore the rate of myopia progression in children in Puerto Rico. Individual children must be monitored to examine the need for treatment of myopia progression.

7.
Microsurgery ; 43(4): 365-372, 2023 May.
Article in English | MEDLINE | ID: mdl-36645336

ABSTRACT

BACKGROUND: The innervated vastus lateralis flap (IVLF) is a barely used possibility for facial palsy reconstruction because of its thickness compared to the gracilis, latissimus dorsi, and pectoralis minor flaps. The aim of this study is to perform a precise description of the intramuscular distribution of the nerve motor branches and its relationship with the vascular pedicle in order to harvest a segmental muscle flap with the best contractile strength to restore facial reanimation. METHODS: The study was performed on 16 adult cadaver thighs identifying the vastus lateralis muscle and the distribution and relationships of its neurovascular pedicle and branches. We evaluated where the nerve pierced the muscle and the course of the nerve within it. Transverse segments of the nerve were obtained from the proximal and distal ends of the nerve and stained using anti-ChAT (Choline acetyltransferase) antibodies which are specific of motor neurons. RESULTS: A nerve for the vastus lateralis from the posterior division of the femoral nerve divided into 2 branches in 56% of cases; the principal branch coursed along the vascular pedicle and pierced the muscle more proximally than the respective vessels, and a minor branch that pierced the muscle 25-60 mm proximally. There were 3 main intramuscular branches. The nerve length (mean 132.65 ± 22.89 mm) allowed to reach the contralateral side of the face in almost all cases (95%). The mean ChAT positive fibers was 351.0 ± 92.4/mm2 at the proximal end, and 270.3 ± 87.9/mm2 at the distal end (p = 0.49). The number of ChAT negative fibers was higher than ChAT positive in both proximal and distal ends of the nerve. CONCLUSION: We propose the IVLF as a one-step surgical flap for facial paralysis reanimation due to the constant neurovascular pattern and lengthy pedicle. The amount of motor fibers in several segments of the nerve is appropriate to produce a powerful contraction for dynamic reconstruction.


Subject(s)
Facial Paralysis , Quadriceps Muscle , Adult , Humans , Quadriceps Muscle/innervation , Surgical Flaps/blood supply , Facial Paralysis/surgery , Facial Paralysis/etiology , Femoral Nerve , Cadaver , Facial Nerve/surgery
8.
J Stroke ; 25(1): 92-100, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36592969

ABSTRACT

BACKGROUND AND PURPOSE: High-grade carotid artery stenosis may alter hemodynamics in the ipsilateral hemisphere, but consequences of this effect are poorly understood. Cortical thinning is associated with cognitive impairment in dementia, head trauma, demyelination, and stroke. We hypothesized that hemodynamic impairment, as represented by a relative time-to-peak (TTP) delay on MRI in the hemisphere ipsilateral to the stenosis, would be associated with relative cortical thinning in that hemisphere. METHODS: We used baseline MRI data from the NINDS-funded Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis-Hemodynamics (CREST-H) study. Dynamic contrast susceptibility MR perfusion-weighted images were post-processed with quantitative perfusion maps using deconvolution of tissue and arterial signals. The protocol derived a hemispheric TTP delay, calculated by subtraction of voxel values in the hemisphere ipsilateral minus those contralateral to the stenosis. RESULTS: Among 110 consecutive patients enrolled in CREST-H to date, 45 (41%) had TTP delay of at least 0.5 seconds and 9 (8.3%) subjects had TTP delay of at least 2.0 seconds, the maximum delay measured. For every 0.25-second increase in TTP delay above 0.5 seconds, there was a 0.006-mm (6 micron) increase in cortical thickness asymmetry. Across the range of hemodynamic impairment, TTP delay independently predicted relative cortical thinning on the side of stenosis, adjusting for age, sex, hypertension, hemisphere, smoking history, low-density lipoprotein cholesterol, and preexisting infarction (P=0.032). CONCLUSIONS: Our findings suggest that hemodynamic impairment from high-grade asymptomatic carotid stenosis may structurally alter the cortex supplied by the stenotic carotid artery.

9.
JAMA Neurol ; 80(1): 73-81, 2023 01 01.
Article in English | MEDLINE | ID: mdl-36374494

ABSTRACT

Importance: Neuroimaging studies have documented racial and ethnic disparities in brain health in old age. It remains unclear whether these disparities are apparent in midlife. Objective: To assess racial and ethnic disparities in magnetic resonance imaging (MRI) markers of cerebrovascular disease and neurodegeneration in midlife and late life. Design, Setting, and Participants: Data from 2 community-based cohort studies, Washington Heights-Inwood Columbia Aging Project (WHICAP) and the Offspring Study of Racial and Ethnic Disparities in Alzheimer Disease (Offspring), were used. Enrollment took place from March 2011 and June 2017, in WHICAP and Offspring, respectively, to January 2021. Of the 822 Offspring and 1254 WHICAP participants approached for MRI scanning, 285 and 176 refused participation in MRI scanning, 36 and 76 were excluded for contraindications/ineligibility, and 4 and 32 were excluded for missing key variables, respectively. Main Outcomes and Measures: Cortical thickness in Alzheimer disease-related regions, white matter hyperintensity (WMH) volume. Results: The final sample included 1467 participants. Offspring participants (497 [33.9%]) had a mean (SD) age of 55 (10.7) years, had a mean (SD) of 13 (3.5) years of education, and included 117 Black individuals (23.5%), 348 Latinx individuals (70%), 32 White individuals (6.4%), and 324 women (65.2%). WHICAP participants (970 [66.1%]) had a mean (SD) age of 75 (6.5) years, had a mean (SD) of 12 (4.7) years of education, and included 338 Black individuals (34.8%), 389 Latinx individuals (40.1%), 243 White individuals (25.1%), and 589 women (65.2%). Racial and ethnic disparities in cerebrovascular disease were observed in both midlife (Black-White: B = 0.357; 95% CI, 0.708-0.007; P = .046) and late life (Black-Latinx: B = 0.149, 95% CI, 0.068-0.231; P < .001; Black-White: B = 0.166; 95% CI, 0.254-0.077; P < .001), while disparities in cortical thickness were evident in late life only (Black-Latinx: B = -0.037; 95% CI, -0.055 to -0.019; P < .001; Black-White: B = -0.064; 95% CI -0.044 to -0.084; P < .001). Overall, Black-White disparities were larger than Latinx-White disparities for cortical thickness and WMH volume. Brain aging, or the association of age with MRI measures, was greater in late life compared with midlife for Latinx (cortical thickness: B = 0.006; 95% CI, 0.004-0.008; P < .001; WMH volume: B = -0.010; 95% CI, -0.018 to -0.001; P = .03) and White (cortical thickness: B = 0.005; 95% CI, 0.002-0.008; P = .001; WMH volume: B = -0.021; 95% CI -0.043 to 0.002; P = .07) participants but not Black participants (cortical thickness: B = 0.001; 95% CI, -0.002 to 0.004; P =.64; WMH volume: B = 0.003; 95% CI, -0.010 to 0.017; P = .61), who evidenced a similarly strong association between age and MRI measures in midlife and late life. Conclusions and Relevance: In this study, racial and ethnic disparities in small vessel cerebrovascular disease were apparent in midlife. In Latinx and White adults, brain aging was more pronounced in late life than midlife, whereas Black adults showed accelerated pattern of brain aging beginning in midlife.


Subject(s)
Alzheimer Disease , Middle Aged , Humans , Female , Aged , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/pathology , Brain/diagnostic imaging , Brain/pathology , Aging/pathology , Cohort Studies , Magnetic Resonance Imaging
10.
Dev Comp Immunol ; 139: 104562, 2023 02.
Article in English | MEDLINE | ID: mdl-36183839

ABSTRACT

Periparturient cows are commonly fed diets supplemented with Niacin (nicotinic acid, NA) because of its anti-lipolytic properties. NA confers its anti-lipolytic effects by activating the hydroxycarboxylic acid 2 receptor (HCA2). HCA2 is also activated by the ketone body beta-hydroxybutyrate (BHB) and circulating BHB levels are elevated in postpartum dairy cows. The HCA2 receptor is highly expressed in bovine polymorphonuclear leukocytes (PMN) and could link metabolic and innate immune responses in cattle. We investigated how HCA2 agonists affected bovine PMN function in vitro. We studied different PMN responses, such as granule release, surface expression of CD11b and CD47, generation of neutrophil extracellular traps (NETs), and apoptosis. NA, BHB, and 4,4aR,5,5aR-tetrahydro-1H-cyclopropa [4,5] cyclopenta [1,2-c] pyrazole-3-carboxylic acid (MK-1903) treatment triggered the release of matrix metalloproteinase 9 (MMP-9), a component of the tertiary granule, from neutrophils. Additionally, all HCA2 agonists induced NETs formation but did not affect surface expression of CD11b and CD47. Finally, none of the HCA2 agonists triggered apoptosis in bovine PMN. This information will give new insights into the potential role of the HCA2 receptor in the bovine innate immune response.


Subject(s)
Matrix Metalloproteinase 9 , Cattle , Animals , Female
11.
12.
Polymers (Basel) ; 14(17)2022 Aug 23.
Article in English | MEDLINE | ID: mdl-36080517

ABSTRACT

Vascular grafts (VGs) are medical devices intended to replace the function of a blood vessel. Available VGs in the market present low patency rates for small diameter applications setting the VG failure. This event arises from the inadequate response of the cells interacting with the biomaterial in the context of operative conditions generating chronic inflammation and a lack of regenerative signals where stenosis or aneurysms can occur. Tissue Engineered Vascular grafts (TEVGs) aim to induce the regeneration of the native vessel to overcome these limitations. Besides the biochemical stimuli, the biomaterial and the particular micro and macrostructure of the graft will determine the specific behavior under pulsatile pressure. The TEVG must support blood flow withstanding the exerted pressure, allowing the proper compliance required for the biomechanical stimulation needed for regeneration. Although the international standards outline the specific requirements to evaluate vascular grafts, the challenge remains in choosing the proper biomaterial and manufacturing TEVGs with good quality features to perform satisfactorily. In this review, we aim to recognize the best strategies to reach suitable mechanical properties in cell-free TEVGs according to the reported success of different approaches in clinical trials and pre-clinical trials.

13.
Biomater Adv ; 134: 112589, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35525749

ABSTRACT

Bioadhesives are intended to facilitate the fast and efficient reconnection of tissues to restore their functionality after surgery or injury. The use of mussel-inspired hydrogel systems containing pendant catechol moieties is promising for tissue attachment under wet conditions. However, the adhesion strength is not yet ideal. One way to overcome these limitations is to add polymeric nanoparticles to create nanocomposites with improved adhesion characteristics. To further enhance adhesiveness, polydopamine nanoparticles with controlled size prepared using an optimized process, were combined with a mussel-inspired hyaluronic acid (HA) hydrogel to form a nanocomposite. The effects of sizes and concentrations of polydopamine nanoparticles on the adhesive profiles of mussel-inspired HA hydrogels were investigated. Results show that the inclusion of polydopamine nanoparticles in nanocomposites increased adhesion strength, as compared to the addition of poly (lactic-co-glycolic acid) (PLGA), and PLGA-(N-hydroxysuccinimide) (PLGA-NHS) nanoparticles. A nanocomposite with demonstrated cytocompatibility and an optimal lap shear strength (47 ± 3 kPa) was achieved by combining polydopamine nanoparticles of 200 nm (12.5% w/v) with a HA hydrogel (40% w/v). This nanocomposite adhesive shows its potential as a tissue glue for biomedical applications.


Subject(s)
Nanocomposites , Nanoparticles , Tissue Adhesives , Adhesives/pharmacology , Hyaluronic Acid/pharmacology , Hydrogels/pharmacology , Indoles , Nanocomposites/therapeutic use , Polymers , Tissue Adhesives/pharmacology
14.
Front Microbiol ; 13: 868347, 2022.
Article in English | MEDLINE | ID: mdl-35422778

ABSTRACT

Background: In the practice of breast augmentation and reconstruction, implant irrigation with various solutions has been widely used to prevent infection and capsular contracture, but to date, there is no consensus on the optimal protocol to use. Recently, application of povidone iodine (PI) for 30 min has shown in vitro to be the most effective irrigating formula in reducing contamination in smooth breast implants. However, as 30 min is not feasible intraoperatively, it is necessary to determine whether shorter times could be equally effective as well as to test it in both smooth and textured implants. Methods: We tested the efficacy of 10% PI at 1', 3', and 5' against biofilms of 8 strains (2 ATCC and 6 clinical) of Staphylococcus spp. on silicone disks obtained from Mentor® and Polytech® implants of different textures. We analyzed the percentage reduction of cfu counts, cell viability and bacterial density between treatment (PI) and control (sterile saline, SS) groups for each time of application. We consider clinical significance when > 25% reduction was observed in cell viability or bacterial density. Results: All textured implants treated with PI at any of the 3 exposure times reduced 100% bacterial load by culture. However, none of the implants reached enough clinical significance in percentage reduction of living cells. Regarding bacterial density, only 25-50 µm Polytxt® Polytech® implants showed significant reduction at the three PI exposure times. Conclusion: PI is able to inhibit bacterial growth applied on the surface of breast implants regardless of the exposure time. However, no significant reduction on living cells or bacterial density was observed. This lack of correlation may be caused by differences in texture that directly affect PI absorption.

15.
Sci Total Environ ; 833: 155068, 2022 Aug 10.
Article in English | MEDLINE | ID: mdl-35413346

ABSTRACT

We have investigated the source and role of light-absorbing impurities (LAIs) deposited on the glaciers of the Olivares catchment, in Central Chile. LAIs can considerably darken (lowered albedo) the glacier surface, enhancing their melt. We combined chemical and mineralogical laboratory analyses of surface and ice core samples with field-based spectral reflectance measurements to investigate the nature and properties of such LAIs. Using remote sensing-based albedo maps, we upscaled local information to glacier-wide coverage. We then used a model to evaluate the sensitivity of surface mass balance to a change in ice and snow albedo. The across-scale surface observations in combination with ice core analysis revealed a history of over half a century of LAIs deposition. We found traces of mining residuals in glacier surface samples. The glaciers with highest mass loss in the catchment present enhanced concentrations of surface dust particles with low reflectance properties. Our results indicate that dust particles with strong light-absorbing capacity have been mobilized from mine tailings and deposited on the nearby glacier surfaces. Large-scale assessment from satellite-based observations revealed darkening (ice albedo lowering) at most investigated glacier tongues from 1989 to 2018. Glacier melt is sensitive to ice albedo. We believe that an accelerated winter and spring snow albedo decrease, partially triggered by surface impurities, might be responsible for the above-average mass loss encountered in this catchment.


Subject(s)
Ice Cover , Snow , Chile , Dust/analysis , Ice Cover/chemistry , Seasons , Snow/chemistry
16.
Head Neck Pathol ; 16(3): 814-817, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35257326

ABSTRACT

Intravascular papillary endothelial hyperplasia (IPEH) is a rare benign non-neoplastic vascular lesion. A typical presentation consists of a subcutaneous nodule that may simulate other clinical entities. Presentation in the oral cavity is uncommon. It is thought to develop as an abnormal proliferative reaction of endothelial cells in a process of impaired thrombogenesis. When endothelial proliferation occurs, a differential diagnosis with a soft tissue sarcoma, in particular an angiosarcoma, should be performed. We report a case of a 68-year-old female patient who presented with a lesion on the upper lip of 3 months' duration. Surgical resection revealed an IPEH. 1 year later, the patient showed a local recurrence requiring excision with clear margins. Pathological and immunohistochemical features can help us distinguish these lesions from those requiring more aggressive treatment. The gold standard is surgical resection with clear margins. Accurate preoperative diagnosis is essential to avoid overtreatment. Emphasis should be placed on clinical, radiological and histological studies.


Subject(s)
Endothelial Cells , Vascular Neoplasms , Aged , Diagnosis, Differential , Female , Humans , Hyperplasia , Mouth Mucosa
17.
Magn Reson Imaging ; 85: 71-79, 2022 01.
Article in English | MEDLINE | ID: mdl-34662699

ABSTRACT

White matter hyperintensities (WMH) are areas of increased signal visualized on T2-weighted fluid attenuated inversion recovery (FLAIR) brain magnetic resonance imaging (MRI) sequences. They are typically attributed to small vessel cerebrovascular disease in the context of aging. Among older adults, WMH are associated with risk of cognitive decline and dementia, stroke, and various other health outcomes. There has been increasing interest in incorporating quantitative WMH measurement as outcomes in clinical trials, observational research, and clinical settings. Here, we present a novel, fully automated, unsupervised detection algorithm for WMH segmentation and quantification. The algorithm uses a robust preprocessing pipeline, including brain extraction and a sample-specific mask that incorporates spatial information for automatic false positive reduction, and a half Gaussian mixture model (HGMM). The method was evaluated in 24 participants with varying degrees of WMH (4.9-78.6 cm3) from a community-based study of aging and dementia with dice coefficient, sensitivity, specificity, correlation, and bias relative to the ground truth manual segmentation approach performed by two expert raters. Results were compared with those derived from commonly used available WMH segmentation packages, including SPM lesion probability algorithm (LPA), SPM lesion growing algorithm (LGA), and Brain Intensity AbNormality Classification Algorithm (BIANCA). The HGMM algorithm derived WMH values that had a dice score of 0.87, sensitivity of 0.89, and specificity of 0.99 compared to ground truth. White matter hyperintensity volumes derived with HGMM were strongly correlated with ground truth values (r = 0.97, p = 3.9e-16), with no observable bias (-1.1 [-2.6, 0.44], p-value = 0.16). Our novel algorithm uniquely uses a robust preprocessing pipeline and a half-Gaussian mixture model to segment WMH with high agreement with ground truth for large scale studies of brain aging.


Subject(s)
Leukoaraiosis , Stroke , White Matter , Aged , Brain/diagnostic imaging , Brain/pathology , Humans , Magnetic Resonance Imaging/methods , Stroke/pathology , White Matter/diagnostic imaging , White Matter/pathology
19.
Biomedica ; 41(4): 660-675, 2021 12 15.
Article in English, Spanish | MEDLINE | ID: mdl-34936252

ABSTRACT

Introduction: Armed conflicts affect territories rich in resources and biodiversity. As a result of the environmental damage caused by violent actions, the health of populations can be affected. Objectives: To assess the risks to human health due to environmental degradation associated with three violent actions in the context of the Colombian armed conflict: Pipeline bombing, informal mining with mercury, and spraying of illicit crops with glyphosate. Materials and methods: We conducted a quantitative evaluation of the risks to individual health associated with armed conflict activities using methodologies focused on the routes of pollutants dispersion, their concentrations in the environment, the exposure of the individuals, and the risks of carcinogenic and non-carcinogenic effects. Results: The risk assessment of the armed conflict-related actions under study evidenced intolerable carcinogenic risk and unacceptable non-carcinogenic risk due to the consumption of water and fish contaminated by polycyclic aromatic hydrocarbons (PAH), mercury, and glyphosate. Conclusions: The study reiterates the inextricable connections existing among the environment, society, and health, as well as the implications of environmental violence for the public health of vulnerable population groups and, in general, for the well-being of all living beings affected by the armed conflict.


Introducción. Los conflictos armados afectan los territorios ricos en recursos y biodiversidad; el daño ambiental causado por las acciones violentas puede afectar la salud de las poblaciones. Objetivos. Evaluar los riesgos para la salud humana debidos a la degradación ambiental asociada con tres acciones violentas en el marco del conflicto armado colombiano: la voladura de oleoductos, la minería informal con mercurio y la aspersión de cultivos ilícitos con glifosato. Materiales y métodos. Se hizo una evaluación cuantitativa de los riesgos para la salud individual asociados con actividades del conflicto armado, usando metodologías que tienen en cuenta la ruta de dispersión de los contaminantes, su concentración en el ambiente, la exposición de los individuos y los riesgos de efectos cancerígenos y no cancerígenos. Resultados. La evaluación de los riesgos asociados con las acciones en el marco del conflicto armado analizadas, evidenció un riesgo cancerígeno intolerable y uno no cancerígeno inaceptable debidos al consumo de agua y peces contaminados por hidrocarburos aromáticos policíclicos, mercurio y glifosato. Conclusiones. El estudio reafirmó las conexiones inextricables que existen entre ambiente, sociedad y salud, y las implicaciones de la violencia ambiental para la salud pública de los grupos poblacionales vulnerables y, en general, para el bienestar de todos los seres vivos afectados por el conflicto armado.


Subject(s)
Environmental Exposure , Mercury , Animals , Armed Conflicts , Colombia/epidemiology , Environmental Exposure/adverse effects , Humans , Mining , Risk Assessment
20.
Biomédica (Bogotá) ; 41(4): 660-675, oct.-dic. 2021. tab
Article in Spanish | LILACS | ID: biblio-1355741

ABSTRACT

Resumen | Introducción. Los conflictos armados afectan los territorios ricos en recursos y biodiversidad; el daño ambiental causado por las acciones violentas puede afectar la salud de las poblaciones. Objetivos. Evaluar los riesgos para la salud humana debidos a la degradación ambiental asociada con tres acciones violentas en el marco del conflicto armado colombiano: la voladura de oleoductos, la minería informal con mercurio y la aspersión de cultivos ilícitos con glifosato. Materiales y métodos. Se hizo una evaluación cuantitativa de los riesgos para la salud individual asociados con actividades del conflicto armado, usando metodologías que tienen en cuenta la ruta de dispersión de los contaminantes, su concentración en el ambiente, la exposición de los individuos y los riesgos de efectos cancerígenos y no cancerígenos. Resultados. La evaluación de los riesgos asociados con las acciones en el marco del conflicto armado analizadas, evidenció un riesgo cancerígeno intolerable y uno no cancerígeno inaceptable debidos al consumo de agua y peces contaminados por hidrocarburos aromáticos policíclicos, mercurio y glifosato. Conclusiones. El estudio reafirmó las conexiones inextricables que existen entre ambiente, sociedad y salud, y las implicaciones de la violencia ambiental para la salud pública de los grupos poblacionales vulnerables y, en general, para el bienestar de todos los seres vivos afectados por el conflicto armado.


Abstract | Introduction: Armed conflicts affect territories rich in resources and biodiversity. As a result of the environmental damage caused by violent actions, the health of populations can be affected. Objectives: To assess the risks to human health due to environmental degradation associated with three violent actions in the context of the Colombian armed conflict: Pipeline bombing, informal mining with mercury, and spraying of illicit crops with glyphosate. Materials and methods: We conducted a quantitative evaluation of the risks to individual health associated with armed conflict activities using methodologies focused on the routes of pollutants dispersion, their concentrations in the environment, the exposure of the individuals, and the risks of carcinogenic and non-carcinogenic effects. Results: The risk assessment of the armed conflict-related actions under study evidenced intolerable carcinogenic risk and unacceptable non-carcinogenic risk due to the consumption of water and fish contaminated by polycyclic aromatic hydrocarbons (PAH), mercury, and glyphosate. Conclusions: The study reiterates the inextricable connections existing among the environment, society, and health, as well as the implications of environmental violence for the public health of vulnerable population groups and, in general, for the well-being of all living beings affected by the armed conflict.


Subject(s)
Environmental Health , Armed Conflicts , Environmental Pollution , Polycyclic Aromatic Hydrocarbons , Risk Assessment , Mercury , Mining
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