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1.
Braz J Med Biol Res ; 55: e11987, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35857997

RESUMO

Early childhood obesity increases the risk of developing metabolic diseases. We examined the early introduction of exercise in small-litter obese-induced rats (SL) on glucose metabolism in the epididymal adipose tissue (AT) and soleus muscle (SM). On day 3 post-birth, pups were divided into groups of ten or three (SL). On day 22, rats were split into sedentary (S and SLS) and exercise (E and SLE) groups. The rats swam three times/week carrying a load for 30 min. In the first week, they swam without a load; in the 2nd week, they carried a load equivalent to 2% of their body weight; from the 3rd week to the final week, they carried a 5% body load. At 85 days of age, an insulin tolerance test was performed in some rats. At 90 days of age, rats were killed, and blood was harvested for plasma glucose, cholesterol, and triacylglycerol measurements. Mesenteric, epididymal, retroperitoneal, and brown adipose tissues were removed and weighed. SM and AT were incubated in the Krebs-Ringer bicarbonate buffer, 5.5 mM glucose for 1 h with or without 10 mU/mL insulin. Comparison between the groups was performed by 3-way ANOVA followed by the Tukey post-hoc test. Sedentary, overfed rats had greater body mass, more visceral fat, lower lactate production, and insulin resistance. Early introduction of exercise reduced plasma cholesterol and contained the deposition of white adipose tissue and insulin resistance. In conclusion, the early introduction of exercise prevents the effects of obesity on glucose metabolism in adulthood in this rat model.


Assuntos
Resistência à Insulina , Obesidade Infantil , Tecido Adiposo/metabolismo , Animais , Glicemia/metabolismo , Criança , Colesterol/metabolismo , Glucose/metabolismo , Humanos , Insulina , Obesidade Infantil/metabolismo , Ratos
2.
J Chem Phys ; 156(9): 094502, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35259882

RESUMO

We report the temperature evolution of hydrogen bond (HB) chains and rings in Mn5[(PO4)2(PO3(OH))2](HOH)4 to reveal conduction pathways based on difference Fourier maps with neutron- and synchrotron x-ray diffraction data. Localized proton dynamics for the five distinct hydrogen sites were observed and identified in this study. Their temperature evaluation over ten orders of magnitude in time was followed by means of quasielastic neutron scattering, dielectric spectroscopy, and ab initio molecular dynamics. Two out of the five hydrogen sites are geometrically isolated and are not suitable for long-range proton conduction. Nevertheless, the detected dc conductivity points to long-range charge transport at elevated temperatures, which occurs most likely (1) over H4-H4 sites between semihelical HB chains (interchain-exchanges) and (2) by rotations of O1-H1 and site-exchanging H4-O10-O5 groups along each semihelical HB chain (intrachain-exchanges). The latter dynamics freeze into a proton-glass state at low temperatures. Rotational and site-exchanging motions of HOH and OH ligands seem to be facilitated by collective motions of framework polyhedra, which we detected by inelastic neutron scattering.

3.
Braz. j. med. biol. res ; 55: e11987, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1384144

RESUMO

Early childhood obesity increases the risk of developing metabolic diseases. We examined the early introduction of exercise in small-litter obese-induced rats (SL) on glucose metabolism in the epididymal adipose tissue (AT) and soleus muscle (SM). On day 3 post-birth, pups were divided into groups of ten or three (SL). On day 22, rats were split into sedentary (S and SLS) and exercise (E and SLE) groups. The rats swam three times/week carrying a load for 30 min. In the first week, they swam without a load; in the 2nd week, they carried a load equivalent to 2% of their body weight; from the 3rd week to the final week, they carried a 5% body load. At 85 days of age, an insulin tolerance test was performed in some rats. At 90 days of age, rats were killed, and blood was harvested for plasma glucose, cholesterol, and triacylglycerol measurements. Mesenteric, epididymal, retroperitoneal, and brown adipose tissues were removed and weighed. SM and AT were incubated in the Krebs-Ringer bicarbonate buffer, 5.5 mM glucose for 1 h with or without 10 mU/mL insulin. Comparison between the groups was performed by 3-way ANOVA followed by the Tukey post-hoc test. Sedentary, overfed rats had greater body mass, more visceral fat, lower lactate production, and insulin resistance. Early introduction of exercise reduced plasma cholesterol and contained the deposition of white adipose tissue and insulin resistance. In conclusion, the early introduction of exercise prevents the effects of obesity on glucose metabolism in adulthood in this rat model.

4.
Curr Opin Struct Biol ; 71: 259-273, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34592682

RESUMO

Accurate predictions from models based on physical principles are the ultimate metric of our biophysical understanding. Although there has been stunning progress toward structure prediction, quantitative prediction of enzyme function has remained challenging. Realizing this goal will require large numbers of quantitative measurements of rate and binding constants and the use of these ground-truth data sets to guide the development and testing of these quantitative models. Ground truth data more closely linked to the underlying physical forces are also desired. Here, we describe technological advances that enable both types of ground truth measurements. These advances allow classic models to be tested, provide novel mechanistic insights, and place us on the path toward a predictive understanding of enzyme structure and function.


Assuntos
Genômica , Fenômenos Biofísicos , Biofísica
5.
Science ; 373(6553)2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34437092

RESUMO

Systematic and extensive investigation of enzymes is needed to understand their extraordinary efficiency and meet current challenges in medicine and engineering. We present HT-MEK (High-Throughput Microfluidic Enzyme Kinetics), a microfluidic platform for high-throughput expression, purification, and characterization of more than 1500 enzyme variants per experiment. For 1036 mutants of the alkaline phosphatase PafA (phosphate-irrepressible alkaline phosphatase of Flavobacterium), we performed more than 670,000 reactions and determined more than 5000 kinetic and physical constants for multiple substrates and inhibitors. We uncovered extensive kinetic partitioning to a misfolded state and isolated catalytic effects, revealing spatially contiguous regions of residues linked to particular aspects of function. Regions included active-site proximal residues but extended to the enzyme surface, providing a map of underlying architecture not possible to derive from existing approaches. HT-MEK has applications that range from understanding molecular mechanisms to medicine, engineering, and design.


Assuntos
Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/antagonistas & inibidores , Fosfatase Alcalina/química , Biocatálise , Domínio Catalítico , Flavobacterium/enzimologia , Hidrólise , Cinética , Microfluídica , Modelos Moleculares , Mutação , Oxigênio/metabolismo , Fosfatos/metabolismo , Conformação Proteica , Dobramento de Proteína , Termodinâmica
6.
Phys Rev E ; 103(2-1): 023104, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33736007

RESUMO

Quantitative, three-dimensional (3D) spatially resolved magnetic resonance flow imaging (flow MRI) methods are presented to characterize structure-flow correlations in a 4-mm-diameter plug of Ketton limestone rock using undersampled k- and q-space data acquisition methods combined with compressed sensing (CS) data reconstruction techniques. The acquired MRI data are coregistered with an X-ray microcomputed tomography (µCT) image of the same rock sample, allowing direct correlation of the structural features of the rock with local fluid transport characteristics. First, 3D velocity maps acquired at 35 µm isotropic spatial resolution showed that the flow was highly heterogeneous, with ∼10% of the pores carrying more than 50% of the flow. Structure-flow correlations were found between the local flow velocities through pores and the size and topology (coordination number) associated with these pores. These data show consistent trends with analogous data acquired for flow through a packing of 4-mm-diameter spheres, which may be due to the microstructure of Ketton rock being a consolidation of approximately spherical grains. Using two-dimensional and 3D visualization of coregistered µCT images and velocity maps, complex pore-scale flow patterns were identified. Second, 3D spatially resolved propagators were acquired at 94 µm isotropic spatial resolution. Flow dispersion within the rock was examined by analyzing each of the 331 776 local propagators as a function of observation time. Again, the heterogeneity of flow within the rock was shown. Quantification of the mean and standard deviation of each of the local propagators showed enhanced mixing occurring within the pore space at longer observation times. These spatially resolved measurements also enable investigation of the length scale of a representative elementary volume. It is shown that for a 4-mm-diameter plug this length scale is not reached.

7.
J Microsc ; 276(2): 63-81, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31587277

RESUMO

There exists a strong motivation to increase the spatial resolution of magnetic resonance imaging (MRI) acquisitions so that MRI can be used as a microscopy technique in the study of porous materials. This work introduces a method for identifying novel data sampling patterns to achieve undersampling schemes for compressed sensing MRI (CS-MRI) acquisitions, enabling 3D spatial resolutions of 17.6 µm to be achieved. A data-driven learning approach is used to derive k-space undersampling schemes for 3D MRI acquisitions from 3D X-ray microcomputed tomography (µCT) datasets acquired at a higher spatial resolution than can be acquired using MRI. The performance of the new sampling approach was compared to other, well-established sampling strategies using simulated MRI data obtained from high-resolution µCT images of rock core plugs. These simulations were performed for a range of different k-space sampling fractions (0.125-0.375) using images of Ketton limestone. The method was then extended to consideration of imaging Estaillades limestone and Fontainebleau sandstone. The results show that the new sampling approach performs as well as or better than conventional variable density sampling and without need for time-consuming parameter optimisation. Further, a bespoke sampling pattern is produced for each rock type. The novel undersampling strategy was employed to acquire 3D magnetic resonance images of a Ketton limestone rock at spatial resolutions of 35 and 17.6 µm. The ability of the k-space sampling scheme produced using the new approach in enabling reconstruction of the pore space characteristics of the rock was then demonstrated by benchmarking against the pore space statistics obtained from high-resolution µCT data. The MRI data acquired at 17.6 µm resolution gave excellent agreement with the pore size distribution obtained from the X-ray microcomputed tomography dataset, while the pore coordination number distribution obtained from the MRI data was slightly skewed to lower coordination numbers. This approach provides a method of producing a k-space undersampling pattern for MRI acquisition at a spatial resolution for which a fully sampled acquisition at that spatial resolution would be impractically long. The approach can be easily extended to other CS-MRI techniques, such as spatially resolved flow and relaxation time mapping. LAY DESCRIPTION: Magnetic resonance imaging (MRI) is widely used to study the microstructure of, and fluid transport phenomena in porous media relevant for engineering applications. A major application is the study of water and hydrocarbon transport in porous sedimentary rocks, which typically have pore sizes smaller than 100 µm. The spatial resolution of routine MRI acquisitions, however, is limited to several hundred µm due to the relatively low sensitivity of the magnetic resonance method. Therefore, there exists a strong motivation to increase the spatial resolution of MRI by one to two orders of magnitude to be able to study these rocks at a pore scale. This work reports the initial step towards achieving this. Three-dimensional images of rock pore structure are acquired at both 35 and 17.6 µm spatial resolution. In ongoing work, these methods are now being incorporated into magnetic resonance velocity imaging methods, thereby enabling imaging of both pore structure and hydrodynamics at these much higher spatial resolutions than were hitherto possible. Although X-ray microcomputed tomography (µCT) produces high spatial resolution images, it is far more limited in being able to spatially map transport processes (i.e. flow) in porous media. This work reports a strategy for accelerating the image acquisition time such that sufficient signal-to-noise ratio (SNR) is achieved to increase the spatial resolution, that is, the voxel size within which there is sufficient SNR within the resulting image. To achieve this, a technique known as compressed sensing is used which exploits undersampling of the acquired data relative to the standard fully sampled image. In MRI, data are acquired in so-called k-space and Fourier transformed to yield the real space image. The challenge, when undersampling, is to optimise the specific points in k-space that are acquired because these will influence the quality of the resulting image. This work reports a straightforward, robust strategy for identifying the optimal sets of k-space points to acquire. The method introduced uses simulated MRI images calculated from high-resolution µCT images of the rocks of interest, from which optimised MRI sampling patterns are obtained. The method does not require any optimisation of parameters for its implementation, which is a significant advantage compared to other strategies. Moreover, we show that the pore space characteristics of the acquired MRI images are in excellent agreement with the same characteristics obtained from a high-resolution µCT image.

8.
Neurología (Barc., Ed. impr.) ; 34(4): 234-240, mayo 2019. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-180813

RESUMO

Introducción: La inexistencia de signos clínicos que diferencien entre crisis epilépticas y episodios paroxísticos no epilépticos hace necesario utilizar métodos diagnósticos específicos, principalmente en pacientes refractarios al tratamiento farmacológico. La monitorización prolongada con videoelectroencefalografía durante las crisis epilépticas evidencia descargas epileptiformes en el EEG ictal y constituye una prueba fundamental para su diagnóstico. La presente investigación pretende caracterizar los eventos paroxísticos y comparar los patrones encontrados en pacientes con diagnóstico de epilepsia refractaria. Métodos: Se realizó un estudio y análisis retrospectivo a partir de los registros médicos de la monitorización prolongada con video EEG de 91 pacientes diagnosticados con epilepsia refractaria durante su internamiento. Resultados: Durante el videoelectroencefalograma prolongado el 76,9% (n = 70) de los pacientes presentaron eventos paroxísticos. El número promedio de eventos fue 3,4 (± 2,7) y su duración fue muy variable. La mayoría de los pacientes (80,0%) presentó las crisis durante vigilia y los principales tipos de eventos registrados fueron: focales con alteración de la conciencia, evolutivos a crisis convulsivas bilaterales y crisis psicógenas no epilépticas. Considerando la totalidad de los eventos paroxísticos, no se objetivan diferencias en cuanto al número o tipo de eventos descritos según el sexo, la edad de inicio de la enfermedad o el sexo y la duración de los eventos, o al número de eventos según el tipo. Las crisis psicógenas no epilépticas se registran predominantemente en vigilia, presentan mayor duración, se inician más tardíamente y ocurren principalmente en mujeres. Conclusiones: Los eventos paroxísticos observados durante la monitorización prolongada con videoelectroencefalograma de pacientes internados con epilepsia refractaria muestran patrones y características similares a los descritos en otras latitudes


Introduction: Given that epileptic seizures and non-epileptic paroxysmal events have similar clinical manifestations, using specific diagnostic methods is crucial, especially in patients with drug-resistant epilepsy. Prolonged video electroencephalography monitoring during epileptic seizures reveals epileptiform discharges and has become an essential procedure for epilepsy diagnosis. The main purpose of this study is to characterise paroxysmal events and compare patterns in patients with refractory epilepsy. Methods: We conducted a retrospective analysis of medical records from 91 patients diagnosed with refractory epilepsy who underwent prolonged video electroencephalography monitoring during hospitalisation. Results: During prolonged video electroencephalography monitoring, 76.9% of the patients (n = 70) had paroxysmal events. The mean number of events was 3.4 ± 2.7; the duration of these events was highly variable. Most patients (80%) experienced seizures during wakefulness. The most common events were focal seizures with altered levels of consciousness, progressive bilateral generalized seizures and psychogenic non-epileptic seizures. Regarding all paroxysmal events, no differences were observed in the number or type of events by sex, in duration by sex or age at onset, or in the number of events by type of event. Psychogenic nonepileptic seizures were predominantly registered during wakefulness, lasted longer, started at older ages, and were more frequent in women. Conclusions: Paroxysmal events recorded during prolonged video electroencephalography monitoring in patients with refractory epilepsy show similar patterns and characteristics to those reported in other latitudes


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto Jovem , Adulto , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Eletroencefalografia/métodos , Convulsões/diagnóstico por imagem , Gravação em Vídeo/métodos , Monitorização Neurofisiológica/métodos , Estudos Retrospectivos , Hospitalização/estatística & dados numéricos , Diagnóstico Diferencial
9.
Neurologia (Engl Ed) ; 34(4): 234-240, 2019 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28318732

RESUMO

INTRODUCTION: Given that epileptic seizures and non-epileptic paroxysmal events have similar clinical manifestations, using specific diagnostic methods is crucial, especially in patients with drug-resistant epilepsy. Prolonged video electroencephalography monitoring during epileptic seizures reveals epileptiform discharges and has become an essential procedure for epilepsy diagnosis. The main purpose of this study is to characterise paroxysmal events and compare patterns in patients with refractory epilepsy. METHODS: We conducted a retrospective analysis of medical records from 91 patients diagnosed with refractory epilepsy who underwent prolonged video electroencephalography monitoring during hospitalisation. RESULTS: During prolonged video electroencephalography monitoring, 76.9% of the patients (n=70) had paroxysmal events. The mean number of events was 3.4±2.7; the duration of these events was highly variable. Most patients (80%) experienced seizures during wakefulness. The most common events were focal seizures with altered levels of consciousness, progressive bilateral generalized seizures and psychogenic non-epileptic seizures. Regarding all paroxysmal events, no differences were observed in the number or type of events by sex, in duration by sex or age at onset, or in the number of events by type of event. Psychogenic nonepileptic seizures were predominantly registered during wakefulness, lasted longer, started at older ages, and were more frequent in women. CONCLUSIONS: Paroxysmal events recorded during prolonged video electroencephalography monitoring in patients with refractory epilepsy show similar patterns and characteristics to those reported in other latitudes.


Assuntos
Epilepsia Resistente a Medicamentos/diagnóstico , Eletroencefalografia/métodos , Diagnóstico Diferencial , Epilepsia Resistente a Medicamentos/fisiopatologia , Feminino , Humanos , Masculino , Monitorização Fisiológica/métodos , Estudos Retrospectivos , Gravação em Vídeo , Adulto Jovem
10.
Clin Exp Allergy ; 48(8): 1025-1034, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29758103

RESUMO

BACKGROUND: The prevalence of sesame food allergy (SFA) has increased over recent years, with the potential of anaphylactic reactions upon exposure. Oral food challenge (OFC) remains the diagnostic standard, yet its implementation may be risky. Commercial skin prick tests (SPT) have a low sensitivity. Investigation of alternate diagnostic methods is warranted. OBJECTIVE: To evaluate the utility of SPT and the basophil activation test (BAT) for SFA diagnosis. METHODS: Eighty-two patients with suspected SFA completed an open OFC to sesame or reported a recent confirmed reaction. Patients were administered skin prick tests (SPT) with commercial sesame seed extract (CSSE) and a high protein concentration sesame extract (HPSE) (100 mg/mL protein). Whole blood from 80 patients was stimulated with sesame seed extract (40-10 000 ng/mL protein) for BAT), assessing CD63 and CD203c as activation markers. RESULTS: Sixty patients (73%) had IgE-mediated reactions to sesame, and 22 (27%) did not react. Receiver operating characteristic (ROC) curve analysis demonstrated an area under the curve (AUC) of 0.87 for HPSE-SPT and 0.66 for CSSE-SPT. At 1000 ng/mL of sesame protein, induction of CD63 and CD203c was weakly but significantly associated with OFC eliciting dose by rank (Spearman's rho = -.42 (P < .01) and -.35 (P < .05) for CD63 and CD203c, respectively). By ROC analysis, the AUC was 0.86 for CD63 and was 0.81 for CD203c sesame-induced basophil expression. Using HPSE-SPT as a first test to definitively diagnose (n = 24) or rule-out (n = 5) SFA and BAT as a second test to diagnose the remainder results in the correct classification of 73 of 80 (91%) patients, leaving one false negative and 4 false positive patients. Two BAT non-responders remain unclassified by this algorithm. CONCLUSIONS & CLINICAL RELEVANCE: While prospective cohort validation is necessary, joint utilization of BAT and SPT with HPSE extract may obviate the need for OFC in most SFA patients.


Assuntos
Alérgenos/imunologia , Basófilos/imunologia , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/imunologia , Sesamum/efeitos adversos , Testes Cutâneos , Teste de Degranulação de Basófilos , Basófilos/metabolismo , Biomarcadores , Feminino , Humanos , Masculino , Fenótipo , Curva ROC , Sensibilidade e Especificidade
11.
Transp Porous Media ; 121(1): 15-35, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31983793

RESUMO

Accurate monitoring of multiphase displacement processes is essential for the development, validation and benchmarking of numerical models used for reservoir simulation and for asset characterization. Here we demonstrate the first application of a chemically-selective 3D magnetic resonance imaging (MRI) technique which provides high-temporal resolution, quantitative, spatially resolved information of oil and water saturations during a dynamic imbibition core flood experiment in an Estaillades carbonate rock. Firstly, the relative saturations of dodecane ( S o ) and water ( S w ) , as determined from the MRI measurements, have been benchmarked against those obtained from nuclear magnetic resonance (NMR) spectroscopy and volumetric analysis of the core flood effluent. Excellent agreement between both the NMR and MRI determinations of S o and S w was obtained. These values were in agreement to 4 and 9% of the values determined by volumetric analysis, with absolute errors in the measurement of saturation determined by NMR and MRI being 0.04 or less over the range of relative saturations investigated. The chemically-selective 3D MRI method was subsequently applied to monitor the displacement of dodecane in the core plug sample by water under continuous flow conditions at an interstitial velocity of 1.27 × 10 - 6 m s - 1 ( 0.4 ft day - 1 ) . During the core flood, independent images of water and oil distributions within the rock core plug at a spatial resolution of 0.31 mm × 0.39 mm × 0.39 mm were acquired on a timescale of 16 min per image. Using this technique the spatial and temporal dynamics of the displacement process have been monitored. This MRI technique will provide insights to structure-transport relationships associated with multiphase displacement processes in complex porous materials, such as those encountered in petrophysics research.

12.
Allergy ; 73(3): 593-601, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29127694

RESUMO

BACKGROUND: Ambiguities exist regarding the diagnosis of tree-nut allergy, necessitating either their elimination or the performance of oral food challenges (OFCs). OBJECTIVE: To examine the coincidences of allergies among tree-nuts and improve diagnostic testing to minimize the need for OFC. METHODS: Eighty-three patients prospectively evaluated for walnut, pecan, cashew, pistachio, hazelnut, and almond allergy. A history of previous reactions was obtained, and standardized skin prick tests (SPTs) using finely ground tree-nut solution and basophil activation tests (BAT) were performed. Patients underwent OFC for each tree-nut they eliminated and to which a reaction in the previous 2 years was not documented. RESULTS: While most patients were sensitized to 5-6 tree-nuts, over 50% were allergic to only 1-2 tree-nuts. The highest rate of allergy in sensitized patients was observed for walnut (74.6%) and cashew (65.6%). The rate of co-allergy for most tree-nuts was <30%. Two-thirds of walnut- and cashew-allergic patients were also allergic to pecan and pistachio, respectively, while all pecan- and pistachio-allergic patients were allergic to walnut and cashew, respectively. Receiver-operating characteristic analysis for SPT and BAT was tree-nut dependent and yielded area under the curve (AUC) values ranging from 0.75 to 0.94. Knowledge of coincident allergies in these pairs along with the combination of SPT and BAT correctly distinguished allergic from tolerant patients for walnut (87%), pecan (66%), cashew (71%), and pistachio (79%). CONCLUSION: The data presented here should assist in differentiating between allergic and tolerant patients, decrease the need for OFC, and allow for appropriate elimination recommendations.


Assuntos
Teste de Degranulação de Basófilos/métodos , Hipersensibilidade a Noz/diagnóstico , Testes Cutâneos/métodos , Criança , Estudos de Coortes , Feminino , Humanos , Masculino
13.
Br J Cancer ; 117(5): 656-665, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28751755

RESUMO

BACKGROUND: Translationally controlled tumour protein (TCTP) is an antiapoptotic protein highly conserved through phylogeny. Translationally controlled tumour protein overexpression was detected in several tumour types. Silencing TCTP was shown to induce tumour reversion. There is a reciprocal repression between TCTP and P53. Sertraline interacts with TCTP and decreases its cellular levels. METHODS: We evaluate the role of TCTP in melanoma using sertraline and siRNA. Cell viability, migration, and clonogenicity were assessed in human and murine melanoma cells in vitro. Sertraline was evaluated in a murine melanoma model and was compared with dacarbazine, a major chemotherapeutic agent used in melanoma treatment. RESULTS: Inhibition of TCTP levels decreases melanoma cell viability, migration, clonogenicity, and in vivo tumour growth. Human melanoma cells treated with sertraline show diminished migration properties and capacity to form colonies. Sertraline was effective in inhibiting tumour growth in a murine melanoma model; its effect was stronger when compared with dacarbazine. CONCLUSIONS: Altogether, these results indicate that sertraline could be effective against melanoma and TCTP can be a target for melanoma therapy.


Assuntos
Biomarcadores Tumorais/antagonistas & inibidores , Biomarcadores Tumorais/genética , Melanoma/genética , RNA Mensageiro/metabolismo , Sertralina/farmacologia , Neoplasias Cutâneas/tratamento farmacológico , Animais , Antineoplásicos Alquilantes/uso terapêutico , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/genética , Sobrevivência Celular/efeitos dos fármacos , Dacarbazina/uso terapêutico , Feminino , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Inativação Gênica , Humanos , Melanoma/metabolismo , Melanoma Experimental/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , RNA Interferente Pequeno/genética , Sertralina/uso terapêutico , Transfecção , Proteína Tumoral 1 Controlada por Tradução , Ensaio Tumoral de Célula-Tronco , Proteína Supressora de Tumor p53/metabolismo
14.
J Magn Reson ; 270: 187-197, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27500742

RESUMO

Three-dimensional (3D) imaging of the fluid distributions within the rock is essential to enable the unambiguous interpretation of core flooding data. Magnetic resonance imaging (MRI) has been widely used to image fluid saturation in rock cores; however, conventional acquisition strategies are typically too slow to capture the dynamic nature of the displacement processes that are of interest. Using Compressed Sensing (CS), it is possible to reconstruct a near-perfect image from significantly fewer measurements than was previously thought necessary, and this can result in a significant reduction in the image acquisition times. In the present study, a method using the Rapid Acquisition with Relaxation Enhancement (RARE) pulse sequence with CS to provide 3D images of the fluid saturation in rock core samples during laboratory core floods is demonstrated. An objective method using image quality metrics for the determination of the most suitable regularisation functional to be used in the CS reconstructions is reported. It is shown that for the present application, Total Variation outperforms the Haar and Daubechies3 wavelet families in terms of the agreement of their respective CS reconstructions with a fully-sampled reference image. Using the CS-RARE approach, 3D images of the fluid saturation in the rock core have been acquired in 16min. The CS-RARE technique has been applied to image the residual water saturation in the rock during a water-water displacement core flood. With a flow rate corresponding to an interstitial velocity of vi=1.89±0.03ftday(-1), 0.1 pore volumes were injected over the course of each image acquisition, a four-fold reduction when compared to a fully-sampled RARE acquisition. Finally, the 3D CS-RARE technique has been used to image the drainage of dodecane into the water-saturated rock in which the dynamics of the coalescence of discrete clusters of the non-wetting phase are clearly observed. The enhancement in the temporal resolution that has been achieved using the CS-RARE approach enables dynamic transport processes pertinent to laboratory core floods to be investigated in 3D on a time-scale and with a spatial resolution that, until now, has not been possible.

15.
Rev Neurol ; 63(2): 58-64, 2016 Jul 16.
Artigo em Espanhol | MEDLINE | ID: mdl-27377981

RESUMO

INTRODUCTION: Thirty percent of patients with epilepsy have recurrent seizures, representing fifteen million people in the world. This population has been scarcely described. AIM: To characterize sociodemographic and clinically the patients diagnosed with refractory epilepsy in a tertiary referral hospital of the Costa Rican social security. PATIENTS AND METHODS: This study presents an analysis of all cases of refractory epilepsy evaluated at the epilepsy unit of San Juan de Dios Hospital from August, 2012 to October, 2014. RESULTS: Clinical records of 91 patients were studied; patients with psychogenic seizures were analyzed separately. The mean age of onset was 13.1 ± 11.1 years, secondary generalized seizures were the predominant type (81.3%), the most frequent etiology was mesial temporal sclerosis (48.3%) and the majority had normal neurological exams and normal or low neuropsychological assessments. Around half (48.8%) of the patients had been medicated with a range of 4-6 antiepileptic drugs, being lamotrigine, carbamazepine, valproic acid and phenytoin the most prescribed. Treatment optimization, neurosurgery, and further analysis were standard recommendations. Sociodemographic characteristics, patient management, and antiepileptic drugs used are similar to the described in other latitudes. Differences between the age of onset and gender; seizure frequency and gender; age of onset and failed treatments and time of evolution of the disease and employment were observed. The percentage and characteristics of recurrent seizures of psychogenic nature found are comparable to other refractory epilepsy studies. CONCLUSION: Sociodemographic characteristics, management of patients, antiepileptic drugs used and the differences observed are similar to those previously described.


TITLE: Caracterizacion de los pacientes con epilepsia refractaria de un hospital de tercer nivel en Costa Rica.Introduccion. El 30% de los pacientes con epilepsia presenta convulsiones recurrentes, porcentaje que representa aproximadamente a 15 millones de personas en el mundo y constituye una poblacion escasamente descrita. Objetivo. Caracterizar sociodemografica y clinicamente la poblacion de pacientes diagnosticados con epilepsia refractaria en un hospital terciario de Costa Rica. Pacientes y metodos. Se analizan los registros medicos de los pacientes con epilepsia refractaria valorados en la unidad de epilepsia del Hospital San Juan de Dios de la Caja Costarricense del Seguro Social desde agosto de 2012 a octubre de 2014. Resultados. Se incluyen los expedientes clinicos de 91 pacientes. La edad media de inicio fue de 13,1 ± 11,1 años. Las crisis secundariamente generalizadas constituyen el tipo predominante (81,3%), la etiologia mas frecuente es la esclerosis mesial temporal (48,3%) y la mayoria de los pacientes presentaba examenes neurologicos normales y valoraciones neuro­psicologicas normales o bajas. Alrededor de la mitad (48,8%) de los pacientes habia sido medicada con un rango de 4-6 farmacos antiepilepticos, y los mas prescritos fueron lamotrigina, carbamacepina, acido valproico y fenitoina. Las principales recomendaciones en estos pacientes fueron: optimizacion de tratamiento, neurocirugia y reingreso. Se observan diferencias entre la edad de inicio y el sexo, la frecuencia de las crisis y el sexo, el tiempo de evolucion de la patologia y la cantidad de tratamientos fallidos, y el tiempo de evolucion de la enfermedad y la ocupacion. Conclusiones. Las caracteristicas sociodemograficas, el manejo de los pacientes, los farmacos antiepilepticos utilizados y las diferencias encontradas son similares a las descritas en otras latitudes.


Assuntos
Epilepsia Resistente a Medicamentos/epidemiologia , Adolescente , Anticonvulsivantes/uso terapêutico , Criança , Pré-Escolar , Costa Rica/epidemiologia , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Humanos , Centros de Atenção Terciária , Adulto Jovem
16.
Allergy ; 71(2): 275-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26482941

RESUMO

Studies examining the long-term effect of oral immunotherapy in food-allergic patients are limited. We investigated cow's milk-allergic patients, >6 months after the completion of oral immunotherapy (n = 197). Questionnaires, skin prick tests, and basophil activation assays were performed. Of the 195 patients contacted, 180 (92.3%) were consuming milk protein regularly. Half experienced adverse reactions, mostly mild. Thirteen patients (6.7%) required injectable epinephrine. Higher reaction rate after immunotherapy was associated with more anaphylactic episodes before treatment and a lower starting dose (OR = 2.1, P = 0.035 and OR = 2.3, P = 0.035, respectively). Reaction rate in patients who were 6-15 months, 15-30 months, or >30 months post-treatment decreased from 0.28/month to 0.21/month to 0.15/month, respectively (P < 0.01). Milk-induced %CD63 and %CD203c expression was significantly lower in patients >24 months vs in patients <24 months post-treatment (P = 0.038 and P = 0.047, respectively). In conclusion, many patients experience mild adverse reactions after completing oral immunotherapy and some require injectable epinephrine. Progressive desensitization, both clinically and in basophil reactivity, occurs over time.


Assuntos
Alérgenos/imunologia , Dessensibilização Imunológica , Hipersensibilidade a Leite/imunologia , Hipersensibilidade a Leite/terapia , Leite/efeitos adversos , Administração Oral , Alérgenos/administração & dosagem , Animais , Bovinos , Pré-Escolar , Dessensibilização Imunológica/efeitos adversos , Dessensibilização Imunológica/métodos , Feminino , Seguimentos , Humanos , Lactente , Masculino , Hipersensibilidade a Leite/diagnóstico , Testes Cutâneos , Resultado do Tratamento
17.
Phys Rev Lett ; 113(16): 167601, 2014 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-25361280

RESUMO

We have studied neutron diffuse scattering in a Sr(0.61)Ba(0.39)Nb(2)O(6) single crystal by neutron backscattering at sub-µeV energy resolution. We can identify two response components with transverse polarization: an elastic (resolution limited) central peak, which monotonically increases with decreasing temperature, and a quasielastic central peak, having a maximum intensity around the ferroelectric phase transition close to 350 K. In contrast to previous neutron experiments on this and other relaxor materials, we were able to observe a temperature dependence of the characteristic frequency of these fluctuations, obeying the same Vogel-Fulcher law as the dynamic part of the dielectric permittivity of this material. In this way our findings provide a first direct link between the Vogel-Fulcher-type frequency dependence of dielectric permittivity and dynamic nanoscale lattice modulations with a transverse correlation length of about 5-10 unit cells.

18.
Arch Pediatr ; 21(6): 614-9, 2014 Jun.
Artigo em Francês | MEDLINE | ID: mdl-24768067

RESUMO

INTRODUCTION: Although instrumental vaginal delivery reduces the risk of neonatal mortality, it increases the risk of specific morbidity including prolonged neonatal discomfort. Previous studies suggest that neonatal exposure to acute pain could have long-term effects on the pain response later in life. The aim of the study was to investigate whether instrumental vaginal delivery may alter the response to a noxious stimulus at the age of two months. METHOD: Newborn infants were enrolled in this prospective observational study after parental consent. A group of children born by instrumental vaginal delivery (group 2) were compared to matched controls born by vaginal delivery (group 1). Pain was assessed in each newborn infant between two and four hours after birth using the scale of pain and discomfort of the newborn baby (EDIN). These children were reassessed for pain response to immunizations (Infanrix(®) and Prevenar(®)) at two months of age using the DAN scale. RESULTS: Thirteen children were enrolled in this study, six in group 1 and seven in group 2. Gestational age, birth weight, Apgar score, and umbilical arterial blood were similar in both groups. The EDIN measured between H2 and H4 was significantly higher in group 2 (median, 4 [IQ, 3] versus 0 [3.25], P<0.05). While the DAN score before and during immunization was similar in the two groups, it was statistically higher in group 2 than in group 1 (4 [3] versus 2 [2.25], P<0.01) within the15 min following the injections. CONCLUSION: These results indicate that birth by instrumental vaginal delivery causes discomfort after birth and increases the pain response to immunization at the age of two months. This study supports the hypothesis that instrumental vaginal delivery may alter pain perception later in life.


Assuntos
Parto Obstétrico/instrumentação , Forceps Obstétrico/efeitos adversos , Percepção da Dor , Vácuo-Extração/efeitos adversos , Adulto , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Medição da Dor , Gravidez , Estudos Prospectivos , Vacinação
19.
Endosc Ultrasound ; 3(Suppl 1): S11-2, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26425508

RESUMO

INTRODUCTION: Male, 72-year-old, morbidly obese, diabetic, admitted for abdominal pain, prostration and fever that started last 3 days. Abdominal ultrasound and abdominal computed tomography scan showed liver injury in the transition of V and VI segments measuring 8.4 cm. Due to the possibility of liver abscess, initiate empirical antibiotic therapy with ampicillin and sulbactam and metronidazole and performed ultrasound-guided percutaneous drainage of liver injury. Negative for malignant cells, with the presence of leukocytes and negative culture. After 2 weeks of treatment, take control image without changing the lesion dimension. New percutaneous drainage with the same results. We opted for performing endoscopic ultrasound (EUS) with fine-needle aspiration (FNA). FNA pathology: Moderately differentiated adenocarcinoma. Immunohistochemistry suggestive of metastasis of the lower gastrointestinal tract. Due this finding, realized colonoscopy, which revealed a vegetating lesion with central ulceration, bleeding, filling almost the entire cecum. Patient was referred for surgical resection of the bowel tumor, which showed moderately differentiated adenocarcinoma infiltrating vegetative and possibly originated from villous adenoma with high-grade dysplasia. DISCUSSION: The finding of metastatic liver abscess of colonic neoplasia is not common. In most cases, the material from the abscess drainage allows the diagnosis, but in this case, even after two ultrasound-guided percutaneous drainage was not obtained conclusive bacteriological or histopathological. Opted for new puncture through EUS, which allowed definitive diagnosis of the condition. CONCLUSION: Metastatic colon neoplasm should be considered in cases of differential diagnosis of liver abscess.

20.
Curr Med Chem ; 19(12): 1780-91, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22414084

RESUMO

In recent years, the effects of cancer chemotherapy and radiotherapy (CT/RT) regimens as they apply to the immune system have been explored. NK cells represent the main cytotoxic arm of the innate immune system, and their functionality is vital to establishing an effective anti tumor immune response. This review examines current CT/RT interventions in light of their effects on NK cell functionality. The effects of CT/RT on the expression of the various ligands for activating and inhibitory NK cell receptors are discussed. Expression of ligands for the activating NKG2D receptor is enhanced by cell stress; accordingly there are numerous reports of their higher expression in cells exposed to various CT/RT agents. In contrast, some agents have been reported to cause ligand shedding, which can serve to inhibit NK cell activity. Reported effects of CT/RT on tumor expression of ligands for the activating Natural Cytotoxicity Receptors, and of HLA class I ligands for NK cell inhibitory receptors are also noted. Additionally, we describe reports concerning the direct effects of CT/RT on NK cell function. Many treatments adversely affect NK cell function directly, but observations made through in vitro systems may differ from those obtained utilizing clinical samples. The effects of CT/RT on both direct NK cell cytotoxicity and on NK cell-mediated Antibody Dependent Cellular Cytotoxicity are explored. Taken together, CT/RT affects NK cell anti-tumor immunity from multiple angles. The interplay is complex, and future work is needed to achieve the optimal synergy between CT/RT and innate as well as adaptive immunity in the treatment of cancer.


Assuntos
Antineoplásicos/uso terapêutico , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/efeitos da radiação , Neoplasias/terapia , Radiação Ionizante , Animais , Quimiorradioterapia , Citotoxicidade Imunológica/efeitos dos fármacos , Citotoxicidade Imunológica/imunologia , Citotoxicidade Imunológica/efeitos da radiação , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Células Matadoras Naturais/imunologia , Neoplasias/imunologia , Neoplasias/metabolismo , Receptores de Células Matadoras Naturais/imunologia , Receptores de Células Matadoras Naturais/metabolismo
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