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1.
PLoS One ; 19(5): e0304054, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38776338

RESUMO

This study explores the Hydrothermal Carbonization (HTC) treatment of lignocellulosic biomass blends, delving into the influence of several key parameters: temperature, additive nature and dosage, residence time, and biomass composition. Rapeseeds, Pinus radiata sawdust, oat husks, and pressed olive served as the studied biomasses. One hundred twenty-eight experiments were conducted to assess the effects on mass yield (MY), energy yield (EY), higher heating value (HHV), and final ash content (ASH) by a Factorial Experimental Design. The derived model equations demonstrated a robust fit to the experimental data, averaging an R2 exceeding 0.94, affirming their predictive accuracy. The observed energy yield ranged between 65% and 80%, notably with sawdust and olive blends securing EY levels surpassing 70%, while rapeseed blends exhibited the highest HHV at 25 MJ/kg. Temperature emerged as the most influential factor, resulting in an 11% decrease in MY and a substantial 2.20 MJ/kg increase in HHV. Contrastingly, blend composition and additive presence significantly impacted ASH and EY, with all blends exhibiting increased ASH in the presence of additives. Higher initial hemicellulose and aqueous extractive content in raw biomass correlated proportionally with heightened HHV.


Assuntos
Biocombustíveis , Biomassa , Biocombustíveis/análise , Lignina/química , Temperatura , Pinus/química , Olea/química , Brassica rapa/química , Temperatura Alta
2.
Clin Transl Oncol ; 26(8): 1896-1907, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38578537

RESUMO

BACKGROUND: Retrospective data suggest an association between bevacizumab efficacy and the incidence of arterial hypertension (AHT). Additionally, epigenetic mechanisms have been related to AHT. METHODS: This prospective observational study conducted by GEICAM Spanish Breast Cancer Research Group included metastatic breast (MBC) or colorectal (mCRC) cancer patients treated with bevacizumab-containing chemotherapy as first-line treatment. Blood pressure (BP) levels were measured (conventional and 24-h Holter monitoring) at baseline and up to cycle 3. Primary endpoint assessed BP levels increase as predictive factor for progression-free survival (PFS). Germline DNA methylation profile was explored in pre-treatment blood samples; principal component analysis was used to define an epigenetic predictive score for increased BP levels. RESULTS: From Oct-2012 to Jul-2016, 143 (78 MBC and 65 mCRC) patients were included. The incidence of AHT according to guidelines was neither predictive of PFS nor of best overall tumor response (BOR). No statistically significant association was observed with systolic BP nor diastolic BP increment for PFS or BOR. Grade 3 and 4 adverse events were observed in 37 and 5% of patients, respectively. We identified 27 sites which baseline methylation status was significantly associated to BP levels increase secondary to bevacizumab-containing chemotherapy. CONCLUSIONS: Neither the frequency of AHT nor the increase of BP levels were predictive of efficacy in MBC and mCRC patients treated with bevacizumab-containing chemotherapy. CLINICAL TRIAL REGISTRY: ClinicalTrials.gov Identifier: NCT01733628.


Assuntos
Bevacizumab , Neoplasias da Mama , Neoplasias Colorretais , Hipertensão , Humanos , Bevacizumab/uso terapêutico , Bevacizumab/administração & dosagem , Feminino , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Pessoa de Meia-Idade , Hipertensão/induzido quimicamente , Estudos Prospectivos , Idoso , Masculino , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Idoso de 80 Anos ou mais , Intervalo Livre de Progressão , Metilação de DNA
3.
PLoS One ; 18(9): e0291838, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37729330

RESUMO

Global population growth and rising consumption levels have significantly increased resource use and energy demand, leading to higher greenhouse gas concentrations and increased waste output. As a result, alternative waste treatment methods for sustainable municipal solid waste (MSW) management are crucial. This research evaluates the efficiency of integrating hydrothermal carbonization (HTC) and gasification for an optimized MSW biomass blend. HTC was conducted for one hour at 220°C in a 5 L reactor, followed by gasification in a hybrid porous medium gasifier. The study investigated the effects of different filtration speeds on combustion temperature and hydrogen concentrations. The results showed that a filtration speed of 35 cm/s resulted in a maximum combustion temperature of 1035.7°C. The temperature remained consistent across filter speeds, while higher velocities yielded higher hydrogen concentrations. Additionally, increasing the filtration velocity raised temperatures in the hybrid bed while increasing the volumetric fraction of biomass decreased maximum temperatures. This research contributes to the understanding of merging HTC and gasification for MSW biomass blend treatment, aiming to reduce environmental impacts and costs while promoting renewable resources for long-term energy production.


Assuntos
Febre , Resíduos Sólidos , Humanos , Porosidade , Biomassa , Hidrogênio
4.
Cancers (Basel) ; 15(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36900229

RESUMO

OBJECTIVE: To analyze, in a cohort of acromegalic patients, the results of the efficiency and safety of radiosurgery (CyberKnife), as well as the prognostic factors associated with disease remission. MATERIAL AND METHODS: Observational, retrospective, longitudinal, and analytical study that included acromegalic patients with persistent biochemical activity after initial medical-surgical treatment, who received treatment with CyberKnife radiosurgery. GH and IGF-1 levels at baseline after one year and at the end of follow-up were evaluated. RESULTS: 57 patients were included, with a median follow-up of four years (IQR, 2-7.2 years). The biochemical remission rate was 45.6%, 33.33% achieved biochemical control, and 12.28% attained biochemical cure at the end of follow-up. A progressive and statistically significant decrease was observed in the comparison of the concentrations of IGF-1, IFG-1 x ULN, and baseline GH at one year and at the end of follow-up. Both cavernous sinus invasion and elevated baseline IGF-1 x ULN concentrations were associated with an increased risk of biochemical non-remission. CONCLUSION: Radiosurgery (CyberKnife) is a safe and effective technique in the adjuvant treatment of GH-producing tumors. Elevated levels of IGF x ULN before radiosurgery and invasion of the cavernous sinus by the tumor could be predictors of biochemical non-remission of acromegaly.

5.
Int J Spine Surg ; 16(3): 521-529, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35772984

RESUMO

BACKGROUND: Patients with epilepsy have a higher risk of skeletal injuries, and some of these fractures occur in the spine during a seizure. Seizure-induced spinal fractures (SISF) are unusual injuries that typically occur in the thoracolumbar spine. Because these skeletal injuries are not well described in the literature, this article aims to analyze the characteristics of this uncommon clinical entity. METHODS: A PubMed and Scopus search adhering to preferred reporting items for systematic reviews and meta-analyses guidelines was performed to include studies reporting patients with SISF. The data gathered from this review were analyzed to characterize this condition. RESULTS: The search yielded 34 articles with a total of 38 patients with SISF. All studies were case reports (level 5 evidence). Most fractures occurred in the thoracic and lumbar spine, and the most common injuries were type A1 and A4 fractures according to the AO spine classification system. Different characteristics of SISF are described including demographics, clinical findings, imaging, and treatment. CONCLUSIONS: SISF should be ruled out in patients who have a recent history of seizures and who report persistent dorsolumbar pain or neurological deficit. SISF usually occurs in the thoracolumbar spine and less frequently in the cervical spine. This review shows that different patterns of neurological deficits, some of them severe, may occur in approximately a quarter of patients with SISF. CLINICAL RELEVANCE: This study provides awareness of an uncommon spine condition. Physicians should suspect SISF in patients with persistent dorsolumbar pain after a seizure.

6.
Infectio ; 26(2): 193-196, Jan.-June 2022. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1356268

RESUMO

Resumen Scedosporium sp. es un género de hongos filamentosos que de forma infrecuente se relaciona a infecciones localizadas o diseminadas en pacientes inmunocom prometidos, o inmunocompetentes con trauma penetrante contaminado. Reportamos el caso de un paciente masculino de 31 años con antecedente de trauma penetrante por arma de fuego requiriendo enucleación de su ojo izquierdo, quien 12 años posterior al trauma inicial presenta necrosis de la cavidad anoftálmica con extrusión del implante y lisis del párpado inferior, finalmente identificando Scedosporium sp. como germen causal, y un mucocele en el seno frontal como reservorio. El paciente recibió tratamiento médico con voriconazol sistémico, desbridamiento quirúrgico amplio, y resección endoscópica del quiste de retención mucoso, con una evolución satisfactoria. Las infecciones micóticas de la cavidad anoftálmica son infrecuentes, requiriendo una alta sospecha diagnóstica y trata miento agresivo para evitar consecuencias potencialmente devastadoras.


Abstract Scedosporium sp. is a genus of filamentous fungi that is infrequently related to localized or disseminated infections in either immunocompromised patients, or immunocompetent patients with penetrating contaminated trauma. We report the case of a 31-year-old patient with a history of penetrating gunshot wound that required enucleation of his left eye, who 12 years after initial trauma presents necrosis of the anophthalmic socket with implant extrusion and lysis of inferior eyelid, finally identifying the causal agent to be Scedosporium sp. The patient received medical treatment with systemic voriconazole, and wide surgical debridement, with a satisfactory evolution. Fungal infections of anophthalmic sockets are infrequent, requiring a high diagnostic suspicion and aggressive treatment to avoid potentially devastating consequences.

7.
Biomimetics (Basel) ; 7(2)2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35466255

RESUMO

We have studied the external surface (elytra) of the Sonoran Desert beetle (Eleodes eschscholtzii). Our aim was to assess whether this species has similar traits to some beetles from the Namibian Desert that are known to have hierarchical micropatterns that allow for water harvesting. We have conducted scanning electron microscopy (SEM) and apparent contact angle experiments on specimens collected at two sampling sites with different ambient humidity. The results show that the beetle's external surface microstructure is composed of a compact array of polygons with randomly scattered protuberances. The density of the polygons in the microstructure is different for individuals collected in different sites: the polygon array is denser in the more humid site and less dense in the drier site. The measured contact angles also depend on the sampling site. For individuals collected in the drier site, the average apparent contact angle is 70°, whereas for the more humid site, the average apparent contact angle is 92°. FT-IR experiments are consistent with the presence of hydrophobic wax compounds in the studied surfaces. Our investigation opens new questions that are currently being addressed by experiments that are underway. For instance, it would be interesting to know whether the observed nanopatterns could be used in biomimetic devices for water harvesting purposes.

8.
Sci Total Environ ; 828: 154474, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35276176

RESUMO

Climate change is the world's greatest challenge today, the reason why it is urgent to optimize industrial processes and find new renewable energy sources. Hydrothermal carbonization (HTC) is one of the Waste-to-Energy technologies with greater projections due to its operative advantages. However, for its large-scale implementation, there are challenges related to the variability of the composition of the waste biomass and the seasonal and geographical availability. This research applied the Life Cycle Analysis methodology to evaluate the environmental impacts caused by three biomasses blends as raw material in the HTC process at laboratory scale. The blends analyzed considered different organic fractions of municipal solid waste (food and pruning) and sewage sludge. The results showed that blend 1 had a lower environmental impact for the case of production in the experimental laboratory level, compared with blends 2 and 3. This is mainly due to its greater calorific value and mass yield, which allows obtaining more hydrochar compared with the other blends, increasing the energy efficiency of the process. Also, between 87.94% and 98.00% of the energy reduction is required to obtain neutral impacts regarding the energy requirements in the experimental laboratory level scenario and the Chilean energy matrix. The processing of blends in HTC has excellent potential in a context where municipal solid wastes have been disposed in sanitary landfills or dumps, as in most emerging countries. Since this study incorporated data from the literature, future studies should perform an elemental analysis to provide experimental and differentiated data.


Assuntos
Carbono , Esgotos , Biomassa , Resíduos Sólidos , Temperatura
9.
Neurosurg Rev ; 45(3): 2013-2026, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35184233

RESUMO

Primary intraventricular hemorrhage (PIVH) is a special subtype of intraventricular hemorrhage (IVH) without a hemorrhagic parenchymal component. Different conditions may cause this uncommon hemorrhage including trauma, vascular anomalies, coagulation disorders, and others. Frequently, PIVH is associated with structural vascular anomalies such as aneurysms, arteriovenous malformations, and dural fistulas. Traditionally, hypertension has been considered a predisposing factor for PIVH. A wide variety of studies have been published describing patients with PIVH; however, studies describing exclusively patients with hypertensive PIVH are lacking in the literature. For this reason, the features of PIVH secondary to hypertension are not well described. The purpose of this study is to analyze and describe the characteristics of hypertensive PIVH. A PubMed and Scopus search adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed to include studies reporting patients with hypertensive PIVH. The search yielded 19 articles reporting retrospective case series. The diagnosis of hypertensive PIVH should be established in patients meeting the following criteria: (a) elevation of blood pressure is observed at admission, (b) a cerebral angiography is negative for vascular anomalies, and (c) other causes of intracranial hemorrhage are ruled out. The prognosis is poorer in patients who present with low Glasgow Coma Score (GCS), old age, hydrocephalus, or more extensive intraventricular bleeding. The results of this study show that hypertension is the most common cause of PIVH, followed by hemorrhage caused by vascular anomalies. Hypertension may be a direct cause of PIVH, but also it may be a predisposing factor for bleeding in cases of an associated vascular anomaly.


Assuntos
Hemorragia Cerebral , Hipertensão , Pressão Sanguínea/fisiologia , Hemorragia Cerebral/diagnóstico , Ventrículos Cerebrais , Humanos , Hipertensão/complicações , Estudos Retrospectivos , Resultado do Tratamento
10.
Andes Pediatr ; 93(4): 579-584, 2022 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-37906858

RESUMO

The Epstein Barr virus is an infectious disease with a high worldwide prevalence, which can present multiple systemic manifestations. The ophthalmological findings are the least frequent and nonspe cific and, therefore, its diagnosis is complicated and delayed; however, it should always be considered as a diagnostic possibility in the presence of atypical ocular and periocular inflammatory clinical pictures. OBJECTIVE: To describe the clinical case of a patient with the presence of a conjunctival mass as the first finding in Epstein Barr virus infection. CLINICAL CASE: A 4-year-old boy with a 4-day history of left upper eyelid edema and ptosis associated with a large, fast-growing, elevated, painful, and salmon-colored upper bulbar conjunctival mass with extension to the upper fornix associated with bilateral cervical and inguinal lymphadenopathy. Initially, a lymphoproliferative disorder was suspected, with blood count with lymphocytosis and atypical lymphocytes, elevated lactate dehydro genase, peripheral blood smear with an increase in white blood cells and some atypical lymphocytes, bone marrow aspirate with a predominance of granulocytes and predominantly CD8-positive T lym phocytes and an increase in Gamma-Delta T lymphocytes. The orbit CT scan showed thickening of the left upper eyelid with peripheral enhancement and the abdominal CT scan showed splenomegaly. Biopsy confirmed chronic Epstein Barr virus infection with positive IgM and indeterminate IgG anti bodies. Symptomatic management was indicated with satisfactory evolution and complete resolution of the conjunctival lesion and lymphadenopathy. CONCLUSION: Epstein Barr virus infection should be considered as a possible diagnosis in atypical ocular and periocular inflammatory manifestations in the pediatric population.


Assuntos
Infecções por Vírus Epstein-Barr , Linfadenopatia , Masculino , Humanos , Criança , Pré-Escolar , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4 , Linfadenopatia/complicações
11.
Bioresour Technol ; 343: 126112, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34648962

RESUMO

The hydrothermal carbonization (HTC) optimization of oat husk was performed using a response surface methodology. Furthermore, anaerobic digestion (AD) of spent liquor and hydrochar addition were evaluated in the biomethane potential (BMP) test. Results found that temperature influences the most in the studied responses (i.e., mass yield (MY) and higher heating value (HHV)). Optimal hydrochar MY (53.8%) and HHV (21.5 MJ/kg) were obtained for 219.2 °C, 30 min, and 0.08 of biomass/water ratio. A successful prediction capability of the optimization approach was observed, archiving an error < 1% between predicted and validated responses. The BMP experiment showed the feasibility of spent liquor as a potential substrate to be treated by AD (144 NmLCH4/gCOD). Hydrochar boosted the methane production of spent liquor increasing up to 17% compared to digestion with no hydrochar addition. These findings provide new insights regarding oat husk valorization by integrating HTC and AD for energy production.


Assuntos
Avena , Carbono , Anaerobiose , Biomassa , Temperatura
12.
Br J Neurosurg ; 36(1): 105-107, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29943648

RESUMO

This paper presents the case of a 68 years old male who was admitted to the hospital after being attacked by another person. The main clinical signs were confusion and severe periorbital edema, findings of gunshot injury were not evident initially. However, a CT scan showed findings compatible with an orbito-cranial perforating gunshot injury. To the best of the author's knowledge, cases like this have not been reported in the literature. This report shows us that an orbito-cranial gunshot injury should be ruled out in cases of severe periorbital edema, especially if the cause of the injury remains unidentified.


Assuntos
Ferimentos por Arma de Fogo , Idoso , Edema , Humanos , Masculino , Crânio , Tomografia Computadorizada por Raios X , Ferimentos por Arma de Fogo/complicações , Ferimentos por Arma de Fogo/diagnóstico por imagem , Ferimentos por Arma de Fogo/cirurgia
13.
Front Neurosci ; 15: 759219, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34955720

RESUMO

The ability to perceive the world is not merely a passive process but depends on sensorimotor loops and interactions that guide and actively bias our sensory systems. Understanding which and how cognitive processes participate in this active sensing is still an open question. In this context, the auditory system presents itself as an attractive model for this purpose as it features an efferent control network that projects from the cortex to subcortical nuclei and even to the sensory epithelium itself. This efferent system can regulate the cochlear amplifier sensitivity through medial olivocochlear (MOC) neurons located in the brainstem. The ability to suppress irrelevant sounds during selective attention to visual stimuli is one of the functions that have been attributed to this system. MOC neurons are also directly activated by sounds through a brainstem reflex circuit, a response linked to the ability to suppress auditory stimuli during visual attention. Human studies have suggested that MOC neurons are also recruited by other cognitive functions, such as working memory and predictability. The aim of this research was to explore whether cognitive processes related to delayed responses in a visual discrimination task were associated with MOC function. In this behavioral condition, chinchillas held their responses for more than 2.5 s after visual stimulus offset, with and without auditory distractors, and the accuracy of these responses was correlated with the magnitude of the MOC reflex. We found that the animals' performance decreased in presence of auditory distractors and that the results observed in MOC reflex could predict this performance. The individual MOC strength correlated with behavioral performance during delayed responses with auditory distractors, but not without them. These results in chinchillas, suggest that MOC neurons are also recruited by other cognitive functions, such as working memory.

14.
Global Spine J ; 11(2): 232-239, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32875852

RESUMO

STUDY DESIGN: Systematic review and illustrative case. OBJECTIVES: Lumbar spinal chondromas (LSCs) are rare spine tumors. The characteristics of these intraspinal lesions are not well described in the literature. The goal of this article is to describe the features of this rare spinal tumor. METHODS: A PubMed and Scopus search adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed to include studies reporting patients with LSCs. The data gathered from this review was analyzed to characterize LSCs. RESULTS: The search yielded 14 cases of patients with LSCs. All studies were case reports (Level V of evidence). Different characteristics of LSCs are described, including demographics, clinical findings, imaging, and treatment. CONCLUSIONS: The results of this review show that LSCs are almost exclusively seen in the extradural space and may adopt a dumbbell shape. LSCs frequently manifest in a very similar way to lumbar disc herniations; therefore, they should be considered in the differential diagnosis of sciatica, especially if magnetic resonance imaging with gadolinium shows peripheral rim enhancement of the lesion. Different degrees of improvement are usually observed after surgical treatment of these patients.

15.
Sci Rep ; 10(1): 14894, 2020 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-32913207

RESUMO

The auditory efferent system comprises descending projections from the cerebral cortex to subcortical nuclei, reaching the cochlear receptor through olivocochlear fibres. One of the functions attributed to this corticofugal system is to suppress irrelevant sounds during selective attention to visual stimuli. Medial olivocochlear neurons can also be activated by sounds through a brainstem reflex circuit. Whether the individual variability of this reflex is related to the cognitive capacity to suppress auditory stimuli is still controversial. Here we propose that the individual strength per animal of the olivocochlear reflex is correlated with the ability to suppress auditory distractors during visual attention in awake chinchillas. The olivocochlear reflex was elicited with a contralateral broad-band noise at ~ 60 dB and ipsilateral distortion product otoacoustic emissions were obtained at different frequencies (1-8 kHz). Fourteen chinchillas were evaluated in a behavioural protocol of visual attention with broad-band noise and chinchilla vocalizations as auditory distractors. Results show that the behavioural performance was affected by both distractors and that the magnitudes of the olivocochlear reflex evaluated at multiple frequencies were relevant for behavioural performance during visual discrimination with auditory distractors. These results stress the ecological relevance of the olivocochlear system for suppressing natural distractors.


Assuntos
Estimulação Acústica , Atenção/fisiologia , Chinchila/fisiologia , Cóclea/fisiologia , Núcleo Olivar/fisiologia , Visão Ocular , Vigília , Animais , Masculino
16.
Environ Sci Pollut Res Int ; 27(30): 38344-38352, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32734542

RESUMO

Some databases report global emissions of certain pollutants. Emissions Database for Global Atmospheric Research (EDGAR) project is one of these, which also records emissions by sources. In this study, the emissions of black and organic carbon and fine particulate matter from the EDGAR database were used as an input to process it in the Sparse Matrix Operator Kernel Emissions (SMOKE) model. We showed the spatial distribution of the fraction of black and organic carbon in particulate matter from each source in the Southern Hemisphere. Also, we extracted these ratios for several cities in the domain of analysis. The results and methodology of this study could improve the emission inventories with bottom-up methodology in areas without information located at Southern Hemisphere. Also, it could be relevant to obtain better performance in air quality modeling at the local level for decision-making on climate change and health effects.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Carbono/análise , Cidades , Mudança Climática , Monitoramento Ambiental , Material Particulado/análise
17.
Rev. Soc. Colomb. Oftalmol ; 53(1): 8-16, 2020.
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1128015

RESUMO

Introducción: las malposiciones palpebrales (ptosis, dermatochalasis superior y ectropión) son de los principales motivos de consulta en el área de cirugía plástica ocular. Aún no hay información concluyente en la literatura sobre los cambios corneales topográficos que se generan con las malposiciones palpebrales y si hay cambios en la topografía corneal posterior a la corrección quirúrgica de estas. Objetivo: determinar los cambios corneales topográficos de los pacientes con malposiciones palpebrales sometidos a corrección quirúrgica. Diseño del estudio: estudio observacional prospectivo longitudinal. Método: pacientes seleccionados por conveniencia a quienes se les realizó corrección quirúrgica de afecciones palpebrales (ptosis, ectropión y dermatochalasis superior) en el Hospital Militar Central de Bogotá entre abril y septiembre de 2019. Se describieron los datos de la topografía corneal previa a la corrección y al mes y tres meses después de esta y la agudeza visual mejor corregida preoperatoria y en la última evaluación postoperatoria realizada. Resultados: se realizó corrección quirúrgica de malposiciones palpebrales a 106 ojos de 54 pacientes. El cilindro medio tuvo un cambio de 0,13 D y el desplazamiento de su eje de 1, 49º. El cambio global en la queratometría media fue de 0,01 D y el grosor corneal central disminuyó 1,5 mcs. En cuanto la agudeza visual mejor corregida hubo un aumento de 0,0415 por escala LogMAR. Conclusión: la cirugía de las malposiciones palpebrales genera cambios topográficos corneales, donde la corrección de ptosis es la que más cambios ocasiona, con persistencia de los cambios a los 3 meses postoperatorio.


Background: palpebral malpositions (ptosis, upper dermatochalasis and ectropion) are the main reasons for consultation in the area of eye plastic surgery. There is still no conclusive information in the literature on the topographic corneal changes that are generated with palpebral malpositions and if there are changes in the corneal topography after surgical correction. Objective: to determine the topographic corneal changes of patients with palpebral malpositions submitted to surgical correction. Study design: longitudinal prospective observational study. Method: patients selected for convenience who underwent surgical correction of palpebral conditions (ptosis, ectropion and upper dermatochalasis) at the Central Militar Hospital of Bogotá between April and September 2019. Corneal topography data prior to correction were described and one month and three months after this and the visual acuity better corrected preoperatively and in the last postoperative evaluation performed. Results: surgical correction of palpebral malpositions was performed in 106 eyes of 54 patients. The middle cylinder had a change of 0,13 D and the displacement of the cylinder axis of 1,49 °. The average global change in mean keratometry was 0,01 D and the central corneal thickness decreased 1,5 mcs. With the best corrected visual acuity there was an increase of 0,0415 per LogMAR scale. Conclusion: palpebral malpositions surgery generates corneal topographic changes, where the correction of ptosis is the one that causes the most changes, with persistence of the changes at 3 months postoperatively.


Assuntos
Blefaroptose/cirurgia , Cirurgia Plástica , Topografia da Córnea , Ectrópio , Ectrópio/cirurgia , Olho
18.
PLoS One ; 14(1): e0208939, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30615632

RESUMO

Evidence shows that selective attention to visual stimuli modulates the gain of cochlear responses, probably through auditory-cortex descending pathways. At the cerebral cortex level, amplitude and phase changes of neural oscillations have been proposed as a correlate of selective attention. However, whether sensory receptors are also influenced by the oscillatory network during attention tasks remains unknown. Here, we searched for oscillatory attention-related activity at the cochlear receptor level in humans. We used an alternating visual/auditory selective attention task and measured electroencephalographic activity simultaneously to distortion product otoacoustic emissions (a measure of cochlear receptor-cell activity). In order to search for cochlear oscillatory activity, the otoacoustic emission signal, was included as an additional channel in the electroencephalogram analyses. This method allowed us to evaluate dynamic changes in cochlear oscillations within the same range of frequencies (1-35 Hz) in which cognitive effects are commonly observed in electroencephalogram works. We found the presence of low frequency (<10 Hz) brain and cochlear amplifier oscillations during selective attention to visual and auditory stimuli. Notably, switching between auditory and visual attention modulates the amplitude and the temporal order of brain and inner ear oscillations. These results extend the role of the oscillatory activity network during cognition in neural systems to the receptor level.


Assuntos
Cóclea/fisiologia , Emissões Otoacústicas Espontâneas/fisiologia , Adulto , Vias Auditivas/fisiologia , Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Eletroencefalografia , Feminino , Humanos , Adulto Jovem
20.
Acta Neurochir (Wien) ; 160(7): 1439-1449, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29802560

RESUMO

BACKGROUND: Glioependymal cysts (GECs) are benign intracranial cysts that have been rarely reported in the literature. The exact pathogenesis of these developmental anomalies is controversial. Moreover, the terminology used to name GECs and other intracranial cysts is confusing because they are undistinguishably reported under a variety of names. The available information in the literature about GECs is scarce, and for this reason, a detailed description about these uncommon lesions is necessary. METHODS: An illustrative case is presented; in addition, a PubMed and Scopus search adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed to include studies reporting patients with GECs. Different information was analyzed in these patients to describe the characteristics of this condition. In addition, different sources of literature were analyzed to complete the description of this clinical entity. RESULTS: The literature review yielded 26 cases of patients with intracranial GECs showing a diversity of clinical manifestations. All studies were case reports or small case series. Different characteristics of GECs are described. Moreover, the authors suggest an updated classification of intracranial benign cysts. CONCLUSIONS: The data collected from this review shows that GECs are rare and very often are erroneously named. They are congenital benign lesions with a neuroectodermal origin that share many radiological characteristics with a variety of intracranial benign cysts. The definite diagnosis of GECs is confirmed by the presence of a glial layer in the cyst wall at histological examination. The appropriate surgical technique should be selected according to the location of the cyst and its proximity to the ventricles or subarachnoid space.


Assuntos
Encefalopatias/diagnóstico por imagem , Cistos/diagnóstico por imagem , Neuroglia/patologia , Idoso , Encefalopatias/patologia , Ventrículos Cerebrais/diagnóstico por imagem , Ventrículos Cerebrais/patologia , Cistos/patologia , Feminino , Humanos , Espaço Subaracnóideo/diagnóstico por imagem , Espaço Subaracnóideo/patologia
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