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1.
J Digit Imaging ; 36(1): 356-364, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36070014

RESUMEN

The objective of this study was to evaluate the influence of the extraction socket (distal or lingual root) and the type of region of interest (ROI) definition (manual or predefined) on the assessment of alveolar repair following tooth extraction using micro-computed tomography (micro-CT). The software package used for scanning, reconstruction, reorientation, and analysis of images (NRecon®, DataViewer®, CT-Analyzer®) was acquired through Bruker < https://www.bruker.com > . The sample comprised the micro-CT volumes of seven Wistar rat mandibles, in which the right first molar was extracted. The reconstructed images were analyzed using the extraction sockets, i.e., the distal and intermediate lingual root and the method of ROI definition: manual (MA), central round (CR), and peripheral round (PR). The bone volume fraction (BV/TV) values obtained were analyzed by two-way ANOVA with Tukey's post hoc test (α = 5%). The distal extraction socket resulted in significantly lower BV/TV values than the intermediate lingual socket for MA (P = 0.001), CR (P < 0.001), and PR (P < 0.001). Regarding the ROI, when evaluating the distal extraction socket, the BV/TV was significantly higher (P < 0.001) for MA than for CR and PR, with a lower BV/TV for CR. However, no significant difference was observed for MA (P = 0.855), CR (P = 0.769), or PR (P = 0.453) in the intermediate lingual extraction socket. The bone neoformation outcome (BV/TV) for alveolar bone repair after tooth extraction is significantly influenced by the ROI and the extraction socket. Using the predefined method with a standardized ROI in the central region of the distal extraction socket resulted in the assessment of bone volume, demonstrating the most critical region of the bone neoformation process.


Asunto(s)
Extracción Dental , Alveolo Dental , Animales , Ratas , Alveolo Dental/cirugía , Microtomografía por Rayos X , Ratas Wistar , Extracción Dental/métodos , Análisis de Varianza
2.
Artículo en Inglés | MEDLINE | ID: mdl-36361088

RESUMEN

There has been a wide use of thermal images of the human body in recent years, specifically images with thermal information of regions of interest (ROI) in the face; this information can be used for epidemiological, clinical, and/or psychological purposes. Due to this, it is important to have plenty of information on temperature in these ROIs in the basal state that allows their use as a reference in terms of their thermal analysis. In this work, a face thermal map of the Mexican population in the basal state (n = 196) is created, adding the comparison between different population groups, such as gender, age, and clinical status, obtaining results of great interest for future research. The t-test for independent samples was applied to the ROIs with normal distribution and Mann−Whitney u-test to the ones that did not present normal distribution. Statistically significant differences were found in some of the ROI comparisons like the corrugator, the supraorbitals, and the chin between the control and clinical groups, as well as in the differentiation by age (p < 0.05).

3.
EClinicalMedicine ; 26: 100508, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33089122

RESUMEN

BACKGROUND: Intrauterine infection with the Zika virus (ZIKV) has been connected to severe brain malformations, microcephaly, and abnormal electrophysiological activity. METHODS: We describe the interictal electroencephalographic (EEG) recordings of 47 children born with ZIKV-derived microcephaly. EEGs were recorded in the first year of life and correlated with brain morphology. In 31 subjects, we tested the association between computed tomography (CT) findings and interictal epileptiform discharges (IED). In eighteen, CTs were used for correlating volumetric measurements of the brainstem, cerebellum, and prosencephalon with the rate of IED. FINDINGS: Twenty-nine out of 47 (62%) subjects were diagnosed as having epilepsy. Those subjects presented epileptiform discharges, including unilateral interictal spikes (26/29, 90%), bilateral synchronous and asynchronous interictal spikes (21/29, 72%), and hypsarrhythmia (12/29, 41%). Interestingly, 58% of subjects with clinical epilepsy were born with rhombencephalon malformations, while none of the subjects without epilepsy showed macroscopic abnormalities in this region. The presence of rhombencephalon malformation was associated with epilepsy (odds ratio of 34; 95% CI: 2 - 654). Also, the presence of IED was associated with smaller brain volumes. Age-corrected total brain volume was inversely correlated with the rate of IED during sleep. Finally, 11 of 44 (25%) subjects presented sleep spindles. We observed an odds ratio of 0·25 (95% CI: 0·06 - 1·04) for having sleep spindles given the IED presence. INTERPRETATION: The findings suggest that certain CT imaging features are associated with an increased likelihood of developing epilepsy, including higher rates of IED and impaired development of sleep spindles, in the first year of life of CZVS subjects. FUNDING: This work was supported by the Brazilian Federal Government through a postdoctoral fellowship for EBS (Talented Youth, Science without Borders), an undergraduate scholarship for AJR (Institutional Program of Science Initiation Scholarships, Federal University of Rio Grande do Norte, Brazil), by International Centre for Genetic Engineering and Biotechnology (CRP/BRA18-05_EC) and by CAPES (Grant number 440893/2016-0), and CNPq (Grant number 88881.130729/2016-01).

4.
Rev Endocr Metab Disord ; 21(1): 37-44, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31965434

RESUMEN

Brown adipose tissue (BAT) is an endocrine adipose tissue with attributes to dissipate energy as heat in response to changes in temperature and diet. Infrared thermography (IRT) has been studied in recent years in the assessment of BAT thermogenesis, as an option to positron emission tomography - computed tomography (PET-CT), because of several advantages. We performed a systematic review on the use of IRT in BAT assessment. Comprehensive online search was performed in different databases. The QUADAS 2 tool was used to evaluate studies' quality. 12 studies fit the inclusion criteria, whereas only one of these was considered of low risk of bias. 10 studies were favorable to IRT appliance in BAT evaluation, observing elevation of supraclavicular skin temperature correlated with BAT activity. Studies were heterogeneous in design, and a meta-analysis was precluded. Further studies with similar methodologies are needed. Conclusion: Despite the large number of published methodologies, IRT is a promising method for detecting BAT activation. Current knowledge already allows a better understanding of thermography to improve and standardize the technique.


Asunto(s)
Tejido Adiposo Pardo/metabolismo , Termografía , Metabolismo Energético , Femenino , Humanos , Rayos Infrarrojos , Masculino , Tomografía Computarizada por Tomografía de Emisión de Positrones , Temperatura Cutánea
5.
Neuroimage Clin ; 18: 932-942, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29876278

RESUMEN

Background: White matter (WM) structural changes, particularly affecting the corpus callosum (CC), seem to be critically implicated in psychosis. Whether such abnormalities are progressive or static is still a matter of debate in schizophrenia research. Aberrant maturation processes might also influence the longitudinal trajectory of age-related CC changes in schizophrenia patients. We investigated whether patients with first-episode schizophrenia-related psychoses (FESZ) would present longitudinal CC and whole WM volume changes over the 5 years after disease onset. Method: Thirty-two FESZ patients and 34 controls recruited using a population-based design completed a 5-year assessment protocol, including structural MRI scanning at baseline and follow-up. The linear effects of disease duration, clinical outcome and antipsychotic (AP) use over time on WM and CC volumes were studied using both voxelwise and volume-based morphometry analyses. We also examined maturation/aging abnormalities through cross-sectional analyses of age-related trajectories of total WM and CC volume changes. Results: No interaction between diagnosis and time was observed, and clinical outcome did not influence CC volumes in patients. On the other hand, FESZ patients continuously exposed to AP medication showed volume increase over time in posterior CC. Curve-estimation analyses revealed a different aging pattern in FESZ patients versus controls: while patients displayed a linear decline of total WM and anterior CC volumes with age, a non-linear trajectory of total WM and relative preservation of CC volumes were observed in controls. Conclusions: Continuous AP exposure can influence CC morphology during the first years after schizophrenia onset. Schizophrenia is associated with an abnormal pattern of total WM and anterior CC aging during non-elderly adulthood, and this adds complexity to the discussion on the static or progressive nature of structural abnormalities in psychosis.


Asunto(s)
Antipsicóticos/uso terapéutico , Cuerpo Calloso/efectos de los fármacos , Cuerpo Calloso/patología , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/patología , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética/métodos , Masculino , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/patología , Esquizofrenia/diagnóstico
6.
Neuroimage Clin ; 19: 848-857, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29946510

RESUMEN

SPG11 mutations are the major cause of autosomal recessive Hereditary Spastic Paraplegia. The disease has a wide phenotypic variability indicating many regions of the nervous system besides the corticospinal tract are affected. Despite this, anatomical and phenotypic characterization is restricted. In the present study, we investigate the anatomical abnormalities related to SPG11 mutations and how they relate to clinical and cognitive measures. Moreover, we aim to depict how the disease course influences the regions affected, unraveling different susceptibility of specific neuronal populations. We performed clinical and paraclinical studies encompassing neuropsychological, neuroimaging, and neurophysiological tools in a cohort of twenty-five patients and age matched controls. We assessed cortical thickness (FreeSurfer software), deep grey matter volumes (T1-MultiAtlas tool), white matter microstructural damage (DTI-MultiAtlas) and spinal cord morphometry (Spineseg software) on a 3 T MRI scan. Mean age and disease duration were 29 and 13.2 years respectively. Sixty-four percent of the patients were wheelchair bound while 84% were demented. We were able to unfold a diffuse pattern of white matter integrity loss as well as basal ganglia and spinal cord atrophy. Such findings contrasted with a restricted pattern of cortical thinning (motor, limbic and parietal cortices). Electromyography revealed motor neuronopathy affecting 96% of the probands. Correlations with disease duration pointed towards a progressive degeneration of multiple grey matter structures and spinal cord, but not of the white matter. SPG11-related hereditary spastic paraplegia is characterized by selective neuronal vulnerability, in which a precocious and widespread white matter involvement is later followed by a restricted but clearly progressive grey matter degeneration.


Asunto(s)
Ganglios Basales/diagnóstico por imagen , Mutación , Proteínas/genética , Paraplejía Espástica Hereditaria/genética , Sustancia Blanca/diagnóstico por imagen , Adolescente , Adulto , Imagen de Difusión Tensora , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neuroimagen , Pruebas Neuropsicológicas , Paraplejía Espástica Hereditaria/diagnóstico por imagen , Adulto Joven
7.
Neuroscience ; 256: 379-91, 2014 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-24183962

RESUMEN

Perinatal nutrient restriction exerts profound influences on brain development. Animals that suffer undernutrition during lactation also display impaired weight gain. Feeding behavior is mainly modulated by neural and hormonal inputs to the hypothalamus. The arcuate-paraventricular neuropeptidergic Y pathway has a prominent role in appetite regulation. The aim of this work was to study the effects of protein undernutrition during lactation on this hypothalamic pathway. We used rats from 5 to 60 postnatal (P) days whose dams were fed a 0% protein diet (PFG) or a normoprotein diet (CG) from P1 to P10. To reproduce the same amount of calorie ingested by the PFG we used an underfed group (UFG). Immunohistochemistry was performed to assess neuropeptide Y (NPY) distribution in the arcuate, periventricular and paraventricular nuclei. Our results showed a NPY immunostaining peak at P10 in all nuclei in CG animals. In UFG animals this peak was observed by P15, while, in the PFG animals only by P20. Our results suggest that the neuropeptidergic arcuate-paraventricular pathway suffered a delay in NPY distribution in undernourished animals, particularly those fed a 0% protein diet, reflecting an effect on this pathway maturation that could explain previously reported alterations on feeding behavior in these animals.


Asunto(s)
Núcleo Arqueado del Hipotálamo/metabolismo , Regulación del Desarrollo de la Expresión Génica/fisiología , Desnutrición/patología , Neuropéptido Y/metabolismo , Núcleo Hipotalámico Paraventricular/metabolismo , Tejido Adiposo/patología , Análisis de Varianza , Animales , Animales Recién Nacidos , Índice de Masa Corporal , Ingestión de Alimentos/fisiología , Femenino , Leptina/sangre , Vías Nerviosas/metabolismo , Embarazo , Ratas , Ratas Wistar
8.
J Pediatr ; 164(1): 186-8, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24064151

RESUMEN

Management of pediatric chronic liver disease is limited by lack of validated noninvasive biomarkers of histologic severity. We demonstrate that magnetic resonance elastography is feasible and accurate in detecting significant hepatic fibrosis in a case series of 35 children with chronic liver disease, including severely obese children.


Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Cirrosis Hepática/diagnóstico , Imagen por Resonancia Magnética/métodos , Adolescente , Niño , Preescolar , Enfermedad Crónica , Diagnóstico por Imagen de Elasticidad/estadística & datos numéricos , Femenino , Humanos , Cirrosis Hepática/etiología , Hepatopatías/complicaciones , Hepatopatías/diagnóstico , Imagen por Resonancia Magnética/estadística & datos numéricos , Masculino , Curva ROC , Reproducibilidad de los Resultados , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Adulto Joven
9.
J Pediatr ; 163(5): 1458-64, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23896183

RESUMEN

OBJECTIVE: To test the hypothesis that international adoption of Chinese and Eastern European girls after 9 months of age results in long-term changes in the neural circuitry supporting monolingual English in later childhood. STUDY DESIGN: Functional magnetic resonance imaging was used to test this hypothesis by comparison with a control group of American-born English speakers (n = 13). Girls now aged 6-10 years adopted from China (n = 13) and Eastern Europe (n = 12) by English-speaking families were recruited through a pediatric hospital-based international adoption center after spending more than 6 months in an orphanage or other institution, a measure of early environmental deprivation. Functional magnetic resonance imaging scans were performed on a 3 Tesla MRI scanner using a verb generation language fluency task. Composite activation maps were computed for each group using a general linear model with random effects analysis. RESULTS: Chinese born adoptees demonstrate atypical lateralization of language function with an apparent shift of temporal-parietal and frontal areas of brain activity toward the right hemisphere. Eastern European adoptees exhibited a rightward shift relative to controls in both frontal and temporal-parietal brain regions. CONCLUSIONS: Significant differences in lateralization between the Chinese and American-born groups in temporal-parietal language areas highlight the possible impact of early tonal Asian language exposure on neural circuitry. Findings suggest that exposure to an Asian language during infancy can leave a long-term imprint on the neural circuitry supporting English language development.


Asunto(s)
Adopción , Mapeo Encefálico/métodos , Desarrollo del Lenguaje , Lenguaje , Imagen por Resonancia Magnética/métodos , Niño , China , Emigrantes e Inmigrantes , Europa Oriental , Femenino , Lóbulo Frontal/fisiología , Humanos , Lóbulo Parietal/fisiología , Lóbulo Temporal/fisiología , Factores de Tiempo , Estados Unidos
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