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1.
Eur J Neurosci ; 60(1): 3491-3504, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38693604

RESUMEN

The continually advancing landscape of neuroscientific and imaging research has broadened our comprehension of sex differences encoded in the human brain, expanding from the hypothalamus and sexual behaviour to encompass the entire brain, including its diverse lobes, structures, and functions. However, less is known about sex differences in the brains of neonates and infants, despite their relevance to various sex-linked diseases that develop early in life. In this review, we provide a synopsis of the literature evidence on sex differences in the brains of neonates and infants at the morphological, structural and network levels. We also briefly overview the present evidence on the sex bias in some brain disorders affecting infants and neonates.


Asunto(s)
Encefalopatías , Encéfalo , Caracteres Sexuales , Humanos , Lactante , Encefalopatías/patología , Encefalopatías/fisiopatología , Masculino , Femenino , Recién Nacido
2.
J Neurosci Res ; 97(4): 480-491, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30548647

RESUMEN

We assessed the sex and the lateralization differences in the corticospinal tract (CST) during the early postnatal period. Twenty-five healthy term neonates (13 girls, aged 39.2 ± 1.2 weeks, and 12 boys aged 38.6 ± 3.0 weeks) underwent Diffusion Tensor Imaging (DTI). Fiber tracking was performed to extract bilaterally the CST pathways and to quantify the parallel (E1 ) and perpendicular (E23 ) diffusions, the apparent diffusion coefficient (ADC), and fractional anisotropy (FA). The measurements were performed on the entire CST fibers and on four segments: base of the pons (CST-Po), cerebral peduncles (CST-CP), posterior limb of the internal capsule (CST-PLIC), and corona-radiata (CST-CR). Significantly higher E1 , lower E23, and higher FA in the right compared to the left were noted in the CST-PLIC of the girls. Significantly lower E23 and lower ADC with higher FA in the right compared to left were observed in the CST-CP of the boys. Moreover, the CST-PLIC of the boys had significantly higher E1 in the right compared to the left. There was a significant increase in left CST E1 of boys when compared with girls. Girls had a significantly lower E1 , lower E23 and, lower ADC in the left CST-CP compared with boys. In addition, girls had a significantly lower E23 and higher FA in the right CST-PLIC compared with boys. Sex differences and lateralization in structure-based segments of the CST were found in healthy term infants during early postnatal period. These findings are vital to understanding motor development of healthy term born neonates to better interpret newborn infants with abnormal neurodevelopment.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Encéfalo/fisiología , Desarrollo Infantil/fisiología , Tractos Piramidales/crecimiento & desarrollo , Tractos Piramidales/fisiología , Anisotropía , Mapeo Encefálico/métodos , Pedúnculo Cerebral/fisiología , Imagen de Difusión por Resonancia Magnética/métodos , Imagen de Difusión Tensora/métodos , Vías Eferentes/crecimiento & desarrollo , Femenino , Humanos , Recién Nacido/crecimiento & desarrollo , Recién Nacido/fisiología , Cápsula Interna/fisiología , Masculino , Factores Sexuales , Sustancia Blanca/fisiología
3.
J Magn Reson Imaging ; 50(5): 1433-1440, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30892782

RESUMEN

BACKGROUND: Multiple sedation regimes may be used to facilitate pediatric MRI scans. These regimes might affect cerebral blood flow and hemodynamics to varying degrees, particularly in children who may be vulnerable to anesthetic side effects. PURPOSE: To compare the effects of propofol monosedation solely (Pm group) vs. a combination of propofol and ketamine (KP group) on brain hemodynamics and perfusion. STUDY TYPE: Prospective double-blind randomized trial. FIELD STRENGTH/SEQUENCES: 1.5T and 3T. 2D-Cine phase contrast (2D-Cine PC) and pseudocontinuous arterial spin labeling (ASL). POPULATION: Children aged from 3 months to 10 years referred for MRI with deep sedation were randomized into either the KP or the Pm group. Perfusion images were acquired with ASL followed by single-slice 2D-Cine PC acquired between the cervical vertebra C2 and C3. ASSESSMENT: Average whole-brain perfusion (WBP ml.min-1 .100 ml-1 ) was extracted from the ASL perfusion maps and total cerebrovascular blood flow (CVF) was quantified by bilaterally summing the flow in the vertebral and the internal carotid arteries. The CVF values were converted to units of ml.min-1 .100 g-1 to calculate the tissue CVF100g (ml.min-1 .100 g-1 ). Images were assessed by a neuroradiologist and data from n = 81 (ASL) and n = 55 (PC) cases with no apparent pathology were entered into the analysis. STATISTICAL TESTS: Multivariate analysis of covariance was performed to compare drug sedation effects on WBP, CVF, and CVF100g . RESULTS: No significant difference in arterial flow was observed (P = 0.57), but the KP group showed significantly higher WBP than the Pm group, covarying for scanner and age (P = 0.003). A correlation analysis showed a significant positive correlation between mean WBP (ml.min-1 .100 g-1 ) and mean CVF100g . DATA CONCLUSION: The KP group showed higher perfusion but no significant difference in vascular flow compared with the Pm group. WBP and CVF100g correlated significantly, but ASL appeared to have more susceptibility to perfusion differences arising from the different sedation regimes. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2019;50:1433-1440.


Asunto(s)
Encéfalo/diagnóstico por imagen , Circulación Cerebrovascular , Sedación Profunda/métodos , Ketamina/administración & dosificación , Imagen por Resonancia Cinemagnética , Propofol/administración & dosificación , Marcadores de Spin , Niño , Preescolar , Análisis por Conglomerados , Método Doble Ciego , Femenino , Hemodinámica , Humanos , Lactante , Masculino , Análisis Multivariante , Perfusión , Estudios Prospectivos
4.
J Neurosci Res ; 95(3): 876-884, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27465433

RESUMEN

Using fiber tracking we investigated the early interhemispheric to cortical development by segmenting the corpus callosum (CC) in five substructures, genu, rostrum, body, isthmus, and splenium, and to examine gender differences in healthy, term neonates. Twenty neonates (11 boys aged 39 ± 2 days, nine girls aged 39 ± 1 days) were scanned in natural sleep with diffusion tensor imging and 35 gradient directions. Fiber tracking was performed using the FACT algorithm. The CC was segments in five substructures on midsagittal imaging. The fiber axial and radial diffusion were measured along with apparent diffusion coefficient and fractional anisotropy. Volume measures were performed for each of these substructures using high-resolution isotropic 3D T1-weighted images. Radial and mean diffusivity in all measured interhemispheric connections were significantly higher in male newborn infants than in female. Second, a gender-dependent regional difference of the measured interhemispheric connections exists. There was no volume difference between boys and girls in any of the five studied sudsubstructures. In addition there was no association between macrostructural and microstructural differences either in boys or girls. The cytoarchitecture and the integrity of the interhemispheric fibers is more developed in female infants in all subdivisions of the CC, except for the isthmus. This might result from a larger axonal diameter, highly packed fibers, or more well-developed myelin sheath. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Mapeo Encefálico , Cuerpo Calloso/diagnóstico por imagen , Cuerpo Calloso/crecimiento & desarrollo , Fibras Nerviosas Mielínicas/fisiología , Anisotropía , Imagen de Difusión Tensora , Femenino , Cabeza/diagnóstico por imagen , Humanos , Imagenología Tridimensional , Lactante , Recién Nacido , Masculino , Vaina de Mielina/fisiología
5.
Clin Genet ; 89(5): 608-13, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26848058

RESUMEN

Premature ovarian insufficiency (POI) affects approximately 1% of women before the age of 40. Genetic contribution is a significant component of POI. In this context, heterozygous mutations in NOBOX, BMP15 and GDF9 have been reported. The objective of our study was to evaluate the prevalence of these genes mutations in 125 unrelated Tunisian patients diagnosed with POI. The screening of NOBOX gene revealed three missense mutations (p.Arg117Trp; p.Gly91Trp and p.Pro619Leu) in eight patients. These mutations were not found in a 200 ethnically matched women without fertility problem. The sequencing of BMP15 and GDF9 gene revealed only previously reported variants. In contrast to previous studies, the prevalence of BMP15 variations is not higher than in the control population. Conversely, 6.4% of the cases present a NOBOX mutations; this high prevalence strengthens the consideration of NOBOX gene as strong autosomal candidate for POI.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Proteínas de Homeodominio/genética , Mutación Missense , Insuficiencia Ovárica Primaria/genética , Factores de Transcripción/genética , Adulto , Alelos , Análisis Mutacional de ADN , Femenino , Frecuencia de los Genes , Pruebas Genéticas/métodos , Pruebas Genéticas/estadística & datos numéricos , Genotipo , Humanos , Prevalencia , Insuficiencia Ovárica Primaria/diagnóstico , Insuficiencia Ovárica Primaria/epidemiología , Túnez/epidemiología
6.
Folia Biol (Praha) ; 62(5): 188-193, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27978413

RESUMEN

In humans, leukocyte telomere length (LTL) reduces with age and is reported to be inversely associated with ageing-related diseases. We measured LTL in leukocyte DNA using a quantitative PCR-based method from 127 blood samples of heart recipients (107 males, 20 females, age 44.1 ± 10.5), followed for up to 30 years. Patients with coronary artery disease survived for a shorter time and also had shorter LTL (both P < 0.05 after adjustment for age and sex) than subjects with dilated cardiomyopathy. Patients with non-cardiac causes of death had shorter LTL than patients with cardiac causes (P < 0.05 after adjustment for age). An inverse correlation between LTL and age (P < 0.03) was observed in patients with non-cardiac causes of death only. Most importantly, LTL was not associated with general survival time in patients after heart transplantation. However, shorter LTL was a marker of non-cardiac causes of death. Different LTLs and survival times were determined in association with aetiology of heart failure (HF).


Asunto(s)
Trasplante de Corazón/mortalidad , Leucocitos/metabolismo , Homeostasis del Telómero , Adulto , Causas de Muerte , Estudios de Seguimiento , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/mortalidad , Humanos , Estimación de Kaplan-Meier , Masculino , Análisis de Supervivencia
7.
Cell Mol Life Sci ; 71(22): 4361-71, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25080109

RESUMEN

Myostatin, a member of the transforming growth factor-ß superfamily, is a potent negative regulator of skeletal muscle growth and is conserved in many species, from rodents to humans. Myostatin inactivation can induce skeletal muscle hypertrophy, while its overexpression or systemic administration causes muscle atrophy. As it represents a potential target for stimulating muscle growth and/or preventing muscle wasting, myostatin regulation and functions in the control of muscle mass have been extensively studied. A wealth of data strongly suggests that alterations in skeletal muscle mass are associated with dysregulation in myostatin expression. Moreover, myostatin plays a central role in integrating/mediating anabolic and catabolic responses. Myostatin negatively regulates the activity of the Akt pathway, which promotes protein synthesis, and increases the activity of the ubiquitin-proteasome system to induce atrophy. Several new studies have brought new information on how myostatin may affect both ribosomal biogenesis and translation efficiency of specific mRNA subclasses. In addition, although myostatin has been identified as a modulator of the major catabolic pathways, including the ubiquitin-proteasome and the autophagy-lysosome systems, the underlying mechanisms are only partially understood. The goal of this review is to highlight outstanding questions about myostatin-mediated regulation of the anabolic and catabolic signaling pathways in skeletal muscle. Particular emphasis has been placed on (1) the cross-regulation between myostatin, the growth-promoting pathways and the proteolytic systems; (2) how myostatin inhibition leads to muscle hypertrophy; and (3) the regulation of translation by myostatin.


Asunto(s)
Atrofia Muscular/metabolismo , Miostatina/metabolismo , Transducción de Señal , Diferenciación Celular , Proliferación Celular , Humanos , Hipertrofia , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Atrofia Muscular/patología , Serina-Treonina Quinasas TOR/metabolismo
8.
J Neurosci Res ; 92(12): 1723-32, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25156430

RESUMEN

Pelizaeus-Merzbacher disease (PMD) is an X-linked disorder of the central nervous system (CNS) caused by a wide variety of mutations affecting proteolipid protein 1 (PLP1). We assessed the effects of PLP1 mutations on water diffusion in CNS white matter by using diffusion tensor imaging. Twelve patients with different PLP1 point mutations encompassing a range of clinical phenotypes were analyzed, and the results were compared with a group of 12 age-matched controls. The parallel (λ// ), perpendicular (λ⊥ ), and apparent diffusion coefficients (ADC) and fractional anisotropy were measured in both limbs of the internal capsule, the genu and splenium of corpus callosum, the base of the pons, and the cerebral peduncles. The mean ADC and λ⊥ in the PMD patient group were both significantly increased in all selected structures, except for the base of the pons, compared with controls. PMD patients with the most severe disease, however, had a significant increase of both λ// and λ⊥ . In contrast, more mildly affected patients had much smaller changes in λ// and λ⊥ . These data suggest that myelin, the structure responsible in part for the λ⊥ barrier, is the major site of disease pathogenesis in this heterogeneous group of patients. Axons, in contrast, the structures mainly responsible for λ// , are much less affected, except within the subgroup of patients with the most severe disease. Clinical disability in patients with PLP1 point mutation is thus likely determined by the extent of pathological involvement of both myelin and axons, with alterations of both structures causing the most severe disease. © 2014 Wiley Periodicals, Inc.


Asunto(s)
Encéfalo/patología , Imagen de Difusión Tensora , Mutación/genética , Proteína Proteolipídica de la Mielina/genética , Enfermedad de Pelizaeus-Merzbacher/genética , Enfermedad de Pelizaeus-Merzbacher/patología , Sustancia Blanca/patología , Adolescente , Adulto , Pedúnculo Cerebral/patología , Niño , Preescolar , Cuerpo Calloso/patología , Evaluación de la Discapacidad , Humanos , Cápsula Interna/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Adulto Joven
9.
J Fr Ophtalmol ; 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37648549

RESUMEN

PURPOSE: The goal of our study is to describe the functional results and preoperative factors predicting visual recovery after successful inverted flap technique and closure of large full-thickness macular holes (FTMH) and to evaluate the correlations between microstructural foveal changes and final visual acuity. METHODS: Retrospective, descriptive, analytical study including 80 eyes of 78 patients with large FTMH; operated by inverted flap technique with successful closure of the macular hole after surgery. All eyes underwent a full preoperative ophthalmic examination and macular B-scan SD-OCT. We performed the classic inverted flap technique for all patients. Postoperatively, all patients were examined at 7 days, 1, 3, 6, 9 and 12 months after surgery. SD-OCT was performed for all patients on each follow-up. Preoperatively, best-corrected visual acuity (BCVA), FTMH size and basal hole diameter were the main outcome measures. Postoperatively, BCVA, macular thickness, integrity of the external limiting membrane (ELM) and ellipsoid zone (EZ) were recorded. RESULTS: Mean age was 62±8.42 years with female predominance. Mean size of the FTMH was 692.59µm, and mean basal hole diameter was 1436.06µm. Mean BCVA improved from 1.06±0.491 LogMAR preoperatively to 0.52±0.32 at 9 months following surgery (P<0.001). At 9 months, the ELM was absent, partial or fully restored in 6.67, 10 and 83.33% respectively. The EZ was absent, partial or fully restored in 6.67, 33 and 63.33% respectively. ELM regeneration always preceded EZ regeneration at every point of follow-up. Final BCVA was statistically correlated with initial hole size (P=0.006, OR=1.056; CI [1.016-1.098]) and mean symptom duration prior to surgery (P=0.001. OR=0.987; CI [0.976-0.998]). Analysis of the ROC curve demonstrated that a hole diameter>478.5µm and symptom duration>5 weeks were correlated with non-improvement of visual acuity, with 81.3% sensibility and 18.7% specificity. CONCLUSION: We report tomographic microstructural foveal changes and functional results following successful large idiopathic FTMH surgery using the classic inverted flap technique. Preoperative parameters such as initial FTMH diameter and mean symptom duration prior to surgery are crucial prognostic factors influencing final visual results.

10.
Cureus ; 14(12): e32758, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36561329

RESUMEN

BACKGROUND: Cardiovascular disease is prevalent worldwide. The goal of this research is to evaluate the knowledge of Riyadh, Saudi Arabia, population about heart attack symptoms and risk factors. METHODOLOGY: A one-year cross-sectional study was carried out. The study was conducted on 385 individuals in Riyadh, Saudi Arabia. We used the Acute Coronary Syndrome Response Index, with additional questions added, such as risk factors of heart attack and physical activity time. An anonymous self-administered online questionnaire was used to collect the data. RESULTS: We collected data from 440 participants, but only 385 were included in the analysis. Males represented 41.4% of the participants. In terms of participant knowledge of heart attack symptoms, we found that chest pain or pressure was the most common (80.5%), followed by shortness of breath (77%) and weakness and fatigue (72.0%). In addition, 90.2% and 90.7% of the participants knew that smoking and obesity were risk factors for heart attacks. Furthermore, 46% of participants said they "would not be at all certain" of identifying the symptoms and indicators of a heart attack in another person and 45.7% "in themselves." We found that males were more likely than females to have low knowledge (RR: 1.84, 95% CI: 1.24:2.72, P = 0.002). CONCLUSION: Our findings suggest that there is a lack of awareness of the heart attack warning signs and symptoms. We propose that future local campaigns focus on increasing awareness and recognition of heart attack symptoms.

11.
Animal ; 16(7): 100556, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35696771

RESUMEN

Animal robustness is a complex trait of importance for livestock production systems and genetic selection. Phenotyping is essential for evaluation of the adaptation of different genotypes to changing environments. This study tested an experimental framework to induce marked deviations in the adaptive responses of suckling beef cows and to identify relevant indicators of responses to characterise individual differences in the robustness of cows. The production and metabolic responses of primiparous suckling Charolais cows to two periods of feed restriction (FR, 50% of their net energy requirements) of different durations were monitored. After calving, 13 cows (aged 39 ±â€¯2 months, BW of 680 ±â€¯42 kg at calving) had ad libitum access to a diet composed of hay and supplemented with concentrate to meet their energy and protein requirements. Starting at 54 ±â€¯6 days postcalving, the cows underwent two periods of FR: 4 days of FR (FR4), which was followed by 17 days of ad libitum intake to study the recovery from FR4, and 10 days of FR (FR10), which was followed by 18 days of ad libitum intake to study the recovery from FR10. The milk yield (MY), BW, body condition score and plasma non-esterified fatty acid (NEFA), ß-hydroxybutyrate, glucose and urea concentrations were measured before, during and after each FR. Among all measured variables, the MY and NEFA concentrations showed the most significant changes in response to FR. A functional data analysis approach was applied to the MY and NEFA data to model the adaptive responses and extract quantifiable indicators of deviation and recovery. Linear correlations (P < 0.03-0.07) between FR4 and FR10 were found for some indicators describing MY and NEFA levels before and after FR. The overall repeatability of MY and NEFA responses between both FR accounted for 46% based on quartile analysis performed on average responses. Moreover, the variance in both the MY and NEFA variables did not differ significantly between FR4 and FR10, despite a trend for higher variances in FR10. Altogether, (1) the calculated variables derived from the functional data analysis of the time patterns of the MY and NEFA accounted for the differences in the cow responses to FR, and (2) the animal responses appeared to show concordance between FR4 and FR10. In conclusion, short-term FR is a relevant framework for studying productive and metabolic adaptive responses in suckling cows and allows the identification of potential robustness indicators.


Asunto(s)
Ácidos Grasos no Esterificados , Lactancia , Ácido 3-Hidroxibutírico , Alimentación Animal , Animales , Bovinos , Dieta/veterinaria , Metabolismo Energético , Femenino , Lactancia/fisiología , Leche/metabolismo
12.
Cereb Cortex ; 20(3): 561-9, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19546156

RESUMEN

Institutional rearing is associated with neurocognitive and behavioral difficulties. Although such difficulties are thought to reflect abnormal neurologic development resulting from early social deprivation (ED) and there is evidence for functional abnormality in children with histories of ED, the impact of early deprivation on brain anatomy has received little study in humans. The present study utilized an objective and sensitive neuroimaging analysis technique (Tract-Based Spatial Statistics) to evaluate white matter fractional anisotropy (FA) and diffusivity in a group of right-handed children with histories of ED (n = 17; mean age = 10.9 + 2.6 years) as compared with age-matched healthy controls (n = 15; mean age = 11.7 + or - 2.8 years). Participants underwent magnetic resonance imaging diffusion tensor imaging sequences and comprehensive neuropsychological evaluations. Results revealed reduced FA in frontal, temporal, and parietal white matter including components of uncinate and superior longitudinal fasciculi, in children with histories of ED, providing further support for limbic and paralimbic abnormalities in children with such histories. Furthermore, white matter abnormalities were associated with duration of time in the orphanage and with inattention and hyperactivity scores. It is suspected that the observed white matter abnormalities are associated with multiple depriving factors (e.g., poor prenatal care, postnatal stress) associated with institutional caregiving.


Asunto(s)
Mapeo Encefálico , Corteza Cerebral/metabolismo , Imagen de Difusión por Resonancia Magnética , Vías Nerviosas/metabolismo , Carencia Psicosocial , Adolescente , Anisotropía , Niño , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Pruebas Neuropsicológicas , Escalas de Valoración Psiquiátrica , Estadística como Asunto
13.
Cereb Cortex ; 20(9): 2103-13, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20019145

RESUMEN

Major frontal lobe tracts and corpus callosum (CC) were investigated in 32 children with autism spectrum disorder (ASD, mean age: 5 years), 12 nonautistic developmentally impaired children (DI, mean age: 4.6 years), and 16 typically developing children (TD, mean age: 5.5 years) using diffusion tensor imaging tractography and tract-based spatial statistics. Various diffusion and geometric properties were calculated for uncinate fasciculus (UF), inferior fronto-occipital fasciculus (IFO), arcuate fasciculus (AF), cingulum (Cg), CC, and corticospinal tract. Fractional anisotropy was lower in the right UF, right Cg and CC in ASD and DI children; in right AF in ASD children; and in bilateral IFO in DI children, compared with TD children. Apparent diffusion coefficient was increased in right AF in both ASD and DI children. The ASD group showed shorter length of left UF and increased length, volume, and density of right UF; increased length and density of CC; and higher density of left Cg, compared with the TD group. Compared with DI group, ASD group had increased length, volume, and density of right UF; higher volume of left UF; and increased length of right AF and CC. Volume of bilateral UF and right AF and fiber density of left UF were positively associated with autistic features.


Asunto(s)
Trastornos Generalizados del Desarrollo Infantil/patología , Cuerpo Calloso/patología , Lóbulo Frontal/patología , Malformaciones del Sistema Nervioso/patología , Niño , Trastornos Generalizados del Desarrollo Infantil/genética , Trastornos Generalizados del Desarrollo Infantil/fisiopatología , Preescolar , Cuerpo Calloso/fisiopatología , Imagen de Difusión Tensora/métodos , Femenino , Lóbulo Frontal/fisiopatología , Lateralidad Funcional/genética , Humanos , Masculino , Malformaciones del Sistema Nervioso/complicaciones , Malformaciones del Sistema Nervioso/fisiopatología , Vías Nerviosas/patología , Vías Nerviosas/fisiopatología , Valor Predictivo de las Pruebas , Valores de Referencia
14.
Hum Brain Mapp ; 31(11): 1665-74, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20162597

RESUMEN

The fronto-striato-thalamic circuit has been implicated in the pathomechanism of Tourette Syndrome (TS). To study white and gray matter comprehensively, we used a novel technique called Tract-Based Spatial Statistics (TBSS) combined with voxel-based analysis (VBA) of diffusion tensor MR images in children with TS as compared to typically developing controls. These automated and unbiased methods allow analysis of cerebral white matter and gray matter regions. We compared 15 right-handed children with TS (mean age: 11.6 ± 2.5 years, 12 males) to 14 age-matched right-handed healthy controls (NC; mean age: 12.29 ± 3.2 years, 6 males). Tic severity and neurobehavioral scores were correlated with FA and ADC values in regions found abnormal by these methods. For white matter, TBSS analysis showed regions of increased ADC in the corticostriatal projection pathways including left external capsule and left and right subcallosal fasciculus pathway in TS group compared to NC group. Within the TS group, ADC for the left external capsule was negatively associated with tic severity (r= -0.586, P = 0.02). For gray matter, VBA revealed increased ADC for bilateral orbitofrontal cortex, left putamen, and left insular cortex. ADC for the right and left orbitofrontal cortex was highly correlated with internalizing problems (r = 0.665; P = 0.009, r = 0.545; P = 0.04, respectively). Altogether, this analysis revealed focal diffusion abnormalities in the corticostriatal pathway and in gray matter structures involved in the fronto-striatal circuit in TS. These diffusion abnormalities could serve as a neuroimaging marker related to tic severity and neurobehavioral abnormalities in TS subjects.


Asunto(s)
Cuerpo Estriado/fisiopatología , Imagen de Difusión Tensora/métodos , Lóbulo Frontal/fisiopatología , Síndrome de Tourette/fisiopatología , Adolescente , Anisotropía , Mapeo Encefálico , Niño , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Fibras Nerviosas Amielínicas/fisiología , Vías Nerviosas/fisiopatología , Índice de Severidad de la Enfermedad , Tálamo/fisiopatología
15.
Tissue Antigens ; 76(5): 380-6, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20604893

RESUMEN

Recent unconfirmed literature data suggest that elevated concentrations of the multifunctional cytokine hepatocyte growth factor (HGF) might be a marker of increased incidence of acute rejection after organ transplantation. The aim of this study was to test the hypothesis that HGF levels may correlate with the rejection and/or with the production of HLA and MHC Class I chain-related antigens A (MICA) specific antibodies. Sixty-three heart transplant recipients were included into the study. Hundred and eighty-five endomyocardial biopsies (EMB) obtained up to 6 months after transplantation were retrospectively analyzed for signs of cellular (CR) and antibody-mediated rejection (AMR). Pre- and post-transplant sera were tested for HGF concentrations and antibodies to HLA class I, class II and MICA antigens by xMap technology (Luminex). Pre-transplant HGF did not correlate with the incidence of CR or AMR. However, higher HGF concentrations correlated significantly with HLA antibody production before and after transplantation (P = 0.006 and P < 0.0001 respectively). Patients with both HLA class I and class II antibodies before transplantation had significantly lower AMR-free survival. Furthermore, recipients with pre-transplant donor-specific antibodies (DSA) had significantly lower AMR-free survival (50%) than recipients without pre-transplant HLA antibodies (90%) and patients with antibodies not specific to donor antigens (92%) (P = 0.005). Post-transplant MICA antibodies tended to be more frequent in patients with AMR (P = 0.063). In conclusion, elevated HGF concentrations in our study were not associated with the incidence of CR and/or AMR but with the presence of HLA-specific antibodies. Testing for DSA before heart transplantation by Luminex may be helpful for the identification of patients with increased risk of AMR.


Asunto(s)
Rechazo de Injerto/etiología , Rechazo de Injerto/inmunología , Antígenos HLA/inmunología , Trasplante de Corazón/efectos adversos , Trasplante de Corazón/inmunología , Factor de Crecimiento de Hepatocito/sangre , Antígenos de Histocompatibilidad Clase I/inmunología , Isoanticuerpos/sangre , Enfermedad Aguda , Adulto , Biomarcadores/sangre , Femenino , Rechazo de Injerto/diagnóstico , Trasplante de Corazón/patología , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos
16.
Physiol Res ; 59(3): 379-384, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19681656

RESUMEN

Despite the widespread use of potent immunosuppressive drugs, such as cyclosporin A and mycophenolate mofetil, ongoing and recurrent cellular rejection remain a common problem after heart transplantation. We aimed to describe the long-term effects of conversion from cyclosporine A to tacrolimus in patients with ongoing and recurrent cellular rejection. This was a single-centre retrospective analysis of 17 heart transplant recipients who were switched from cyclosporine A to tacrolimus due to ongoing (5 patients) or recurrent cellular rejection (12 patients). We studied long-term efficacy and safety of this approach. 167 endomyocardial biopsies were performed during a mean follow-up of 69.1 +/- 12.7 months. Thirteen biopsies (7.8%) in eight patients (47%) revealed higher grades of acute cellular rejection (Banff 2). However, they were not hemodynamically significant and did not require intravenous antirejection therapy. The mean rejection score was reduced significantly. Conversion to tacrolimus was tolerated in 82% pts without any significant side effects during a long-term follow-up. In conclusion, the conversion to tacrolimus in heart transplant recipients with ongoing or recurrent acute cellular rejection was safe and effective also during a long-term follow-up.


Asunto(s)
Ciclosporina/administración & dosificación , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Trasplante de Corazón/efectos adversos , Inmunosupresores/administración & dosificación , Tacrolimus/administración & dosificación , Enfermedad Aguda , Adulto , Biopsia , Ciclosporina/efectos adversos , Femenino , Rechazo de Injerto/inmunología , Rechazo de Injerto/patología , Humanos , Inmunosupresores/efectos adversos , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Tacrolimus/efectos adversos , Factores de Tiempo , Resultado del Tratamiento
17.
Chronobiol Int ; 37(2): 189-208, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31809592

RESUMEN

Ecological artificial light at night (ALAN) has been increasingly associated with negative effects on the behavior and ecology of wild birds. However, the impacts of short-term bright ALAN on the temporal biology of companion animals and the underlying mediating mechanism are unknown. We evaluated impacts of 1X60-min/middle night ALAN (200 lux, λDominant = 460 nm) nightly with or without melatonin administration on growth performance, reproductive capacity, food and water intake, and stress responses in Australian budgerigars (Melopsittacus undulatus) under captivity. 36 birds were housed in pairs under natural photoperiod and were equally divided into three groups: control, natural conditions; ALAN, control + ALAN; and melatonin, ALAN + melatonin in the drinking water during the dark period. Birds were regularly monitored for body mass, egg production, and hatchability over four months. Food intake, water consumption, and daily rhythm of fecal corticosterone were also evaluated. ALAN increased mass gain, food intake, water consumption, and drastically decreased reproductive capacity, whereas stress responses were markedly augmented. Melatonin restored food and water intake to control levels but partly reversed mass gain. Melatonin failed to ameliorate the impaired reproductive capacity despite reducing the stress responses to basal levels. These results suggest that the ALAN-induced negative impacts cannot be attributed solely to direct effects of melatonin suppression or/and exacerbated stress responses and the involvement of other photoperiodic pathway components warrant further studies. Finally, the results of our study may be of importance for improving the housing conditions of companion animals at least as concern bright ALAN exposures.


Asunto(s)
Melatonina , Animales , Australia , Aves , Ritmo Circadiano , Luz , Melatonina/farmacología , Fotoperiodo
18.
J Fr Ophtalmol ; 43(7): 604-610, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32631693

RESUMEN

INTRODUCTION: Childhood ocular trauma is a preventable cause of visual impairment and blindness worldwide. The purpose of our study was to determine demographic, etiologic, and clinical characteristics, visual outcome, and factors affecting visual prognosis in children with open globe injuries (OGI) and to analyze the predictive value of ocular trauma scoring systems for OGI in children. METHODS: We conducted a retrospective study enrolling 120 pediatric patients hospitalized for OGI from January 2010 to March 2017. Age, gender, date of trauma, time between trauma and presentation, place and circumstances of injury, etiology, visual acuity (VA), wound location and type of injury based on the Birmingham Eye Trauma Terminology, and the clinical signs were recorded. We recorded the number of surgical procedures performed, complications and visual outcomes. RESULTS: The mean age was 7.38 years. In all, 62.5% of the patients were male, and 37.5% were female. The gender ratio was observed to decrease with increasing age. The mean time interval between injury and consultation was 22.80±42.68hours. Injuries usually occurred at home (80%) followed by playgrounds and sports venues (8.3%), the street (6.7%) and school (5%). All of the OGI's were accidental, and the main context was play (70%). The most common traumas were penetrating injury (60.8%) and metal (30%) objects. Penetrating trauma accounted for 68.3% of cases, followed by rupture (27.5%) and intraocular foreign body (IOFB) (7.5%). Initial VA was<1/10 in 59.2% of cases, and the point of entry was the cornea in 65.8% of cases. Final VA was<1/10 in 39.69% of all cases. FVA was significantly correlated with BCVA prior to the surgery, mechanism of the trauma, wound location and size, and other associated lesions. The Ocular Trauma Score (OTS) and the Pediatric Ocular Trauma Score (POTS) were significantly correlated with final VA. CONCLUSION: OGI's in children occurs most frequently in school-age boys. Prognosis is determined by presenting visual acuity, trauma score, and wound severity and location.


Asunto(s)
Lesiones Oculares Penetrantes/diagnóstico , Lesiones Oculares Penetrantes/epidemiología , Adolescente , Ceguera/diagnóstico , Ceguera/epidemiología , Ceguera/etiología , Niño , Preescolar , Cuerpos Extraños en el Ojo/diagnóstico , Cuerpos Extraños en el Ojo/epidemiología , Cuerpos Extraños en el Ojo/etiología , Lesiones Oculares Penetrantes/patología , Femenino , Humanos , Lactante , Masculino , Pronóstico , Estudios Retrospectivos , Rotura/diagnóstico , Rotura/epidemiología , Rotura/etiología , Índices de Gravedad del Trauma , Túnez/epidemiología , Baja Visión/diagnóstico , Baja Visión/epidemiología , Baja Visión/etiología , Agudeza Visual
19.
Diagnostics (Basel) ; 10(6)2020 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-32526946

RESUMEN

This prospective study investigated the effects of fold-over oversampling on phase-offset background errors with 2D-Cine phase contrast (Cine-PC) magnetic resonance imaging (MRI). It was performed on brain MRI and compared to conventional Full-field of view FOV coverage and it was tested with two different velocity encoding (Venc) values. We chose Venc = 100 mm/s to encode cerebrospinal fluid (CSF) flows in the aqueduct and 600 mm/s to encode blood flow in the carotid artery. Cine-PC was carried out on 10 healthy adult volunteers followed simultaneously by an acquisition on static agar-gel phantom to measure the phase-offset background errors. Pixel-wise correction of both the CSF and the blood flows was calculated through 32 points of the cardiac-cycle. We compared the velocity-to-noise ratio, the section area, the absolute and the corrected velocity (peak; mean and minimum), the net flow, and the stroke volume before and after correction. We performed the statistical T-test to compare Full-FOV and fold-over and Bland-Altman plots to analyze their differences. Our results showed that following phase-offset error correction, the blood stroke-volume was significantly higher with Full-FOV compared to fold-over. We observed a significantly higher CSF mean velocity and net flow values in the fold-over option. Compared to Full-FOV, fold-over provides a significantly larger section area and significantly lower peak velocity-offset in the aqueduct. No significant difference between the two coverages was reported before and after phase-offset in blood flow measurements. In conclusion, fold-over oversampling can be chosen as an alternative to increase spatial resolution and accurate cerebral flow quantification in Cine-PC.

20.
Cereb Cortex ; 18(11): 2659-65, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18359780

RESUMEN

To investigate frontal lobe white matter in children with autism spectrum disorder (ASD), we performed diffusion tensor imaging (DTI) in 50 ASD children (mean age: 57.5 +/- 29.2 months, 43 males) and 16 typically developing children (mean age: 82.1 +/- 41.4 months, 11 males). The apparent diffusion coefficient (ADC) was significantly higher for whole frontal lobe (P = 0.011), long (P < 0.001) and short range (P = 0.0126) association fibers in ASD group. There was a trend toward statistical significance in the fractional anisotropy (FA) of whole frontal lobe fibers (P = 0.11). FA was significantly lower in ASD group for short range fibers (P = 0.0031) but not for long range fibers (P = not significant [NS]). There was no between-group difference in the number of frontal lobe fibers (short and long) (P = NS). The fiber length distribution was significantly more positively skewed in the normal population than in the ASD group (P < 0.001). The long range association fibers of frontal lobe were significantly longer in ASD group (P = 0.026 for both left and right hemispheres). Abnormal frontal FA and ADC may be due to white matter organization abnormalities in ASD. Lack of evidence for excessive short range connectivity in ASD in this study may need to be re-examined with future advances in DTI technology.


Asunto(s)
Trastorno Autístico/patología , Imagen de Difusión por Resonancia Magnética , Lóbulo Frontal/patología , Anisotropía , Niño , Preescolar , Femenino , Humanos , Masculino , Fibras Nerviosas/patología , Vías Nerviosas/patología
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