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1.
Alzheimers Dement ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963127

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-38392373

RESUMO

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.
Proc Natl Acad Sci U S A ; 117(8): 3996-4006, 2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32047039

RESUMO

The future response of the Antarctic ice sheet to rising temperatures remains highly uncertain. A useful period for assessing the sensitivity of Antarctica to warming is the Last Interglacial (LIG) (129 to 116 ky), which experienced warmer polar temperatures and higher global mean sea level (GMSL) (+6 to 9 m) relative to present day. LIG sea level cannot be fully explained by Greenland Ice Sheet melt (∼2 m), ocean thermal expansion, and melting mountain glaciers (∼1 m), suggesting substantial Antarctic mass loss was initiated by warming of Southern Ocean waters, resulting from a weakening Atlantic meridional overturning circulation in response to North Atlantic surface freshening. Here, we report a blue-ice record of ice sheet and environmental change from the Weddell Sea Embayment at the periphery of the marine-based West Antarctic Ice Sheet (WAIS), which is underlain by major methane hydrate reserves. Constrained by a widespread volcanic horizon and supported by ancient microbial DNA analyses, we provide evidence for substantial mass loss across the Weddell Sea Embayment during the LIG, most likely driven by ocean warming and associated with destabilization of subglacial hydrates. Ice sheet modeling supports this interpretation and suggests that millennial-scale warming of the Southern Ocean could have triggered a multimeter rise in global sea levels. Our data indicate that Antarctica is highly vulnerable to projected increases in ocean temperatures and may drive ice-climate feedbacks that further amplify warming.

4.
Microsurgery ; 43(4): 365-372, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36645336

RESUMO

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.


Assuntos
Paralisia Facial , Músculo Quadríceps , Adulto , Humanos , Músculo Quadríceps/inervação , Retalhos Cirúrgicos/irrigação sanguínea , Paralisia Facial/cirurgia , Paralisia Facial/etiologia , Nervo Femoral , Cadáver , Nervo Facial/cirurgia
5.
Ann Plast Surg ; 87(4): 415-420, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33560002

RESUMO

ABSTRACT: Late seroma related to breast silicone implants is a rare complication. Interest for its characterization has grown after its association with the recently described breast implant-associated anaplastic large cell lymphoma. The differential diagnosis includes infectious diseases, mechanical and traumatic causes, tumors, postpartum seroma, and inflammatory, allergic, or idiopathic causes.Sarcoidosis has been associated with breast silicone implants over the last decades, but it has never been reported as a cause of breast effusion. We describe a rare presentation of sarcoidosis as a late breast implant seroma simulating the clinical features and radiologic findings of breast implant-associated anaplastic large cell lymphoma and highlight that sarcoidosis can be suspected by the presence of nonnecrotizing epithelioid granulomas in the cytology, with a characteristic inverted ratio of CD4/CD8 T cells.The aims of this article are to review the current evidence about sarcoidosis related to silicone implants and breast cancer, provide a new alternative in the differential diagnosis of late seroma, and advise the scientific community how early implant removal can improve the disease.


Assuntos
Implantes de Mama , Neoplasias da Mama , Linfoma Anaplásico de Células Grandes , Sarcoidose , Implantes de Mama/efeitos adversos , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Linfoma Anaplásico de Células Grandes/diagnóstico , Linfoma Anaplásico de Células Grandes/etiologia , Seroma/diagnóstico , Seroma/etiologia
6.
J Foot Ankle Surg ; 60(4): 839-844, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33509723

RESUMO

Soft tissue defects of the distal third of the leg and ankle, which frequently expose tendon, bone or osteosynthesis material, are difficult to cover and pose a major challenge to the plastic surgeon. Traditional reconstructive options for this region usually require complex flaps which made them unsuitable for elderly patients or those with multiple comorbidities. We hereby present the reverse dermis flap as an easy and reliable choice to cover this type of wounds and refer our experience in 9 cases in which clinical, operative, and follow-up data were recorded. Of the 9 flaps performed, 8 survived completely and 1 presented a partial flap necrosis, requiring additional surgery. No other operative procedure was required. In conclusion, the reversed dermis flap is a simple, quick, noninvasive, and safe technique for coverage of noble structures such as tendon or bone in the distal third of the leg that every plastic surgeon should incorporate in his surgical armamentary.


Assuntos
Traumatismos da Perna , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Idoso , Tornozelo , Derme , Humanos , Perna (Membro) , Traumatismos da Perna/cirurgia , Lesões dos Tecidos Moles/cirurgia , Resultado do Tratamento
7.
Analyst ; 143(2): 420-428, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29236110

RESUMO

Cryopreservation can be used for long-term preservation of tissues and organs. It relies on using complex mixtures of cryoprotective agents (CPAs) to reduce the damaging effects of freezing, but care should be taken to avoid toxic effects of CPAs themselves. In order to rationally design cryopreservation strategies for tissues, it is important to precisely determine permeation kinetics of the protectants that are used to ensure maximum permeation, while minimizing the exposure time and toxicity effects. This is particularly challenging with protectant solutions consisting of multiple components each with different physical properties and diffusing at a different rate. In this study, we show that an attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) setup can be used to simultaneously monitor diffusion of multiple components in a mixture into tissues in real time. Diffusion studies were done with decellularized heart valves using a sucrose-DMSO mixture as well as vitrification solution VS83. To assess diffusion kinetics of different solutes in mixtures, the increase in specific infrared absorbance bands was monitored during diffusion through the tissue. Solute specific wavenumber ranges were selected, and the calculated area was assumed to be proportional to the CPA concentration in the tissue. A diffusion equation based on Fick's second law of diffusion fitted the experimental data quite well, and clear differences in permeation rates were observed among the different mixture components dependent on molecular size and physical properties.


Assuntos
Criopreservação , Crioprotetores/análise , Vitrificação , Animais , Difusão , Dimetil Sulfóxido , Congelamento , Valvas Cardíacas , Concentração Osmolar , Sacarose , Suínos
8.
Adv Virus Res ; 117: 81-119, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37832992

RESUMO

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.


Assuntos
Gastroenterite , Mamastrovirus , Animais , Criança , Humanos , Idoso , Mamastrovirus/genética , Genótipo , Filogenia , Mamíferos
9.
Dev Comp Immunol ; 139: 104562, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36183839

RESUMO

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.


Assuntos
Metaloproteinase 9 da Matriz , Bovinos , Animais , Feminino
10.
Int J Ophthalmol ; 16(3): 434-441, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36935800

RESUMO

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.

11.
JAMA Neurol ; 80(1): 73-81, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36374494

RESUMO

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.


Assuntos
Doença de Alzheimer , Pessoa de Meia-Idade , Humanos , Feminino , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Envelhecimento/patologia , Estudos de Coortes , Imageamento por Ressonância Magnética
12.
J Stroke ; 25(1): 92-100, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36592969

RESUMO

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.

13.
Front Bioeng Biotechnol ; 11: 1257778, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37799814

RESUMO

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.

14.
Antibiotics (Basel) ; 12(7)2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37508183

RESUMO

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.

15.
Biomater Adv ; 134: 112589, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35525749

RESUMO

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.


Assuntos
Nanocompostos , Nanopartículas , Adesivos Teciduais , Adesivos/farmacologia , Ácido Hialurônico/farmacologia , Hidrogéis/farmacologia , Indóis , Nanocompostos/uso terapêutico , Polímeros , Adesivos Teciduais/farmacologia
16.
Head Neck Pathol ; 16(3): 814-817, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35257326

RESUMO

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.


Assuntos
Células Endoteliais , Neoplasias Vasculares , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Hiperplasia , Mucosa Bucal
17.
Sci Total Environ ; 833: 155068, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35413346

RESUMO

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.


Assuntos
Camada de Gelo , Neve , Chile , Poeira/análise , Camada de Gelo/química , Estações do Ano , Neve/química
18.
Magn Reson Imaging ; 85: 71-79, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34662699

RESUMO

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.


Assuntos
Leucoaraiose , Acidente Vascular Cerebral , Substância Branca , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Acidente Vascular Cerebral/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
19.
Front Microbiol ; 13: 868347, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35422778

RESUMO

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.

20.
Polymers (Basel) ; 14(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36080517

RESUMO

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.

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