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1.
J Fr Ophtalmol ; 44(8): 1229-1236, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34243998

RESUMO

PURPOSE: To examine the reproducibility of spectral domain optical coherence tomography (SD-OCT) segmented ganglion cell complex and circumpapillary retinal nerve fiber layer (cpRNFL) measurements in children with primary congenital glaucoma (PCG) in comparison with healthy children. METHODS: 12 children with PCG (G1) and 24 healthy children (G2) were recruited. The following SD-OCT measurements (Spectralis, Heidelberg Engineering) were made in one eye per child: total macular thickness (MT), thicknesses in several subfields and volumes of the three inner macular layers, macular retinal nerve fiber layer (mRNFL), ganglion cell layer (GCL), and inner plexiform layer (IPL) and cpRNFL thickness. In a single day, an expert operator obtained 3 circumpapillary and 3 macular measurements in each participant to determine intraoperator variability. Intraoperator repeatability was defined by the coefficient of variation (CoV) and intraclass correlation (ICC). RESULTS: ICC was excellent in both groups for cpRNFL measurements (G1 ICC=0.950 and G2 ICC=0.995) and for MT was excellent in G1 (ICC=0.957) and moderate in G2 (ICC=552). For the inner macular layer measurements, all ICCs were better in PCG group (mRNFL-ICC: 0.915 vs. 0.765; ICC-GCL: 0.584 vs. 0.263 and ICC-IPL: 0.979 vs. 0.742; G1 and G2 respectively). Greater CoV were recorded for macular measurements (from 0.71% to 9.82%) compared to cpRNFL measurements (from 0.52% to 1.50%). CONCLUSION: In children with PCG, Spectralis SD-OCT showed excellent intrasession repeatability for cpRNFL, MT, mRNFL and IPL measurements and moderated for GCL measurements. For all macular measurements, ICC were higher in children with PCG than healthy children.


Assuntos
Glaucoma , Macula Lutea , Criança , Estudos Transversais , Glaucoma/diagnóstico , Humanos , Pressão Intraocular , Reprodutibilidade dos Testes , Células Ganglionares da Retina , Tomografia de Coerência Óptica
2.
Eur J Neurosci ; 53(5): 1498-1516, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33220131

RESUMO

While the involvement of executive processes in mind wandering is largely undebated, their exact relationship is subject to an ongoing debate and rarely studied dynamically within-subject. Several brain-stimulation studies using transcranial direct current stimulation (tDCS) have attempted to modulate mind-wandering propensity by stimulating the left dorsolateral prefrontal cortex (DLPFC) which is an important hub in the prefrontal control network. In a series of three studies testing a total of N = 100 participants, we develop a novel task that allows to study the dynamic interplay of mind wandering, behavioural varibility and the flexible recruitment of executive resources as indexed by the randomness (entropy) of movement sequences generated by our participants. We consistently find that behavioural variability is increased and randomness is decreased during periods of mind wandering. Interestingly, we also find that behavioural variability interacts with the entropy-MW effect, opening up the possibility to detect distinct states of off-focus cognition. When applying a high-definition transcranial direct-current stimulation (HD-tDCS) montage to the left DLPFC, we find that propensity to mind wander is reduced relative to a group receiving sham stimulation.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Atenção , Controle Comportamental , Função Executiva , Humanos , Córtex Pré-Frontal
3.
Neuroimage ; 224: 117412, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33011417

RESUMO

Mind wandering reflects the shift in attentional focus from task-related cognition driven by external stimuli toward self-generated and internally-oriented thought processes. Although such task-unrelated thoughts (TUTs) are pervasive and detrimental to task performance, their underlying neural mechanisms are only modestly understood. To investigate TUTs with high spatial and temporal precision, we simultaneously measured fMRI, EEG, and pupillometry in healthy adults while they performed a sustained attention task with experience sampling probes. Features of interest were extracted from each modality at the single-trial level and fed to a support vector machine that was trained on the probe responses. Compared to task-focused attention, the neural signature of TUTs was characterized by weaker activity in the default mode network but elevated activity in its anticorrelated network, stronger functional coupling between these networks, widespread increase in alpha, theta, delta, but not beta, frequency power, predominantly reduced amplitudes of late, but not early, event-related potentials, and larger baseline pupil size. Particularly, information contained in dynamic interactions between large-scale cortical networks was predictive of transient changes in attentional focus above other modalities. Together, our results provide insight into the spatiotemporal dynamics of TUTs and the neural markers that may facilitate their detection.


Assuntos
Atenção/fisiologia , Ondas Encefálicas/fisiologia , Rede de Modo Padrão/diagnóstico por imagem , Pupila , Pensamento/fisiologia , Adolescente , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Rede de Modo Padrão/fisiologia , Eletroencefalografia , Potenciais Evocados/fisiologia , Feminino , Neuroimagem Funcional , Voluntários Saudáveis , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia , Tamanho do Órgão , Máquina de Vetores de Suporte , Adulto Jovem
4.
Andrologia ; 50(2)2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28730608

RESUMO

This study was undertaken to evaluate the effects of Aframomum melegueta on male rat ejaculation using in/ex copula techniques. For the in copula experiment, rats were orally treated with aqueous or methanolic extract (20 and 100 mg/kg) of A. melegueta for 14 days. Each rat was mated with a primed receptive female on days 0, 7 and 14 of treatment, and the ejaculatory latency and post-ejaculatory interval were measured. In the ex copula experiment, the electromyography of the bulbospongiosus muscles and intraseminal pressure were recorded in spinal rats after mechanical (urethral and penile) and pharmacological stimulations (intravenous injection of dopamine (5 mg/kg) and, aqueous or methanolic extract of A. melegueta, 2.5; 5; 10 and 20 mg/kg). Furthermore, the effect of dopamine on fictive ejaculation was monitored in rats orally pre-treated with A. melegueta extracts (20 and 100 mg/kg) for 7 or 14 days. Treatment with the aqueous or methanolic extract of A. melegueta significantly decreased the ejaculatory latency (p < .05) and post-ejaculatory interval (p < .01) after 14 days. In spinal rats, mechanical or pharmacological stimulations triggered fictive ejaculation. In animals orally pre-treated with A. melegueta extracts, the pro-ejaculatory effect of dopamine was more expressed. Present findings show that A. melegueta possesses pro-ejaculatory effects.


Assuntos
Ejaculação/efeitos dos fármacos , Extratos Vegetais/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Zingiberaceae/química , Administração Oral , Animais , Dopamina/farmacologia , Feminino , Injeções Intravenosas , Masculino , Metanol/química , Modelos Animais , Ratos , Ratos Wistar , Água/química
5.
Asian Pac J Trop Med ; 7(8): 609-619, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25149374

RESUMO

OBJECTIVE: To investigate the effects of Dracaena arborea (D. arborea) on the sexual behavior parameters in experienced type-1 diabetic rats. METHODS: Aqueous and ethanol (100 and 500 mg/kg respectively) extracts of dried root barks of D. arborea, sildenafil citrate (1.44 mg/kg), trimethylamine-N-oxide (TMAO, 20 mg/kg) and distilled water (10 mL/kg) were orally administered to 4 weeks streptozotocin-induced diabetic rats. Mount latency and frequency (ML, MF), intromission latency and frequency (IL, IF) and post-ejaculatory interval (PEI) were measured by ejaculatory series during 90 min once a week for 4 weeks. Glycemia was determined at the beginning and at the end of the treatment. RESULTS: D. arborea did not show any major antihyperglycemic effects. Compared to the control group, a significant (P<0.05-0.001) increase in MF and IF was noticed in rats treated with sildenafil citrate (89.71% and 90.07% respectively), aqueous (500 mg/kg, 88.08% and 88.74% respectively) and ethanol (100 mg/kg; 89.53% and 89.17 respectively) extracts of D. arborea after two weeks (series 1) of treatment. ML, IL and PEI were significantly (P<0.05-0.001) decreased after 4 weeks of daily treatment [sildenafil citrate (96.31, 96.31% and 34.98%), and D. arborea aqueous 500 mg/kg (94.33, 94.33% and 66.60%) and ethanol extracts 100 mg/kg (96.98, 97.08% and 64.26%)]. CONCLUSIONS: These aphrodisiac potentials of D. arborea in experienced diabetic rats could be due to the antioxidant and androgenic properties of phenols, flavonoids, saponins and sterols revealed in the plant extracts.


Assuntos
Afrodisíacos/farmacologia , Diabetes Mellitus Experimental , Dracaena/química , Extratos Vegetais/farmacologia , Animais , Afrodisíacos/química , Glicemia , Ejaculação/efeitos dos fármacos , Feminino , Masculino , Piperazinas , Casca de Planta/química , Extratos Vegetais/química , Raízes de Plantas/química , Purinas , Comportamento Sexual Animal/efeitos dos fármacos , Citrato de Sildenafila , Sulfonamidas
6.
ISRN Hepatol ; 2013: 276563, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-27398385

RESUMO

Background/Aim. Metabolic Bone disorders are well-recognized extrahepatic complications of cirrhosis. The aim was to report their prevalence and the associated factors to their development in patients with viral cirrhosis. Patients and Methods. All consecutive patients with viral cirrhosis were prospectively enrolled. Parathyroid hormone, 25-hydroxyvitamin D, liver function, and phosphocalcic tests were measured in all patients. Bone mineral density was measured at the lumbar spine and total hip by dual-energy X-ray absorptiometry. Data were analyzed using SPSS software. Results. Forty-six cirrhotic patients were included with hepatitis C (87%) and hepatitis B (13%). The Child-Pugh score was grade A in 87% of cases and grade B in 13%. Thirty-seven patients had decreased bone mineral density with osteopenia in 24 patients and osteoporosis in 13 patients. Decreased 25-hydroxyvitamin D was found in 95.6% of cases. Bone disorders were significantly more frequent in old patients with low body mass index, long duration of liver disease, and low 25-hydroxyvitamin D level. None of these factors was an independent factor associated with bone disorders. Conclusion. Our study revealed a high prevalence of metabolic bone disorders among viral cirrhotic patients. Consequently, bone mineral density assessment should be performed systematically in all cirrhotic patients.

7.
J Nanosci Nanotechnol ; 12(8): 6800-3, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22962825

RESUMO

Cu-chalcogenide thin films were prepared using a two stage method: one step electrodeposition of CuISe and CIGSe, and the sulfurisation of CISe to prepare CISSe thin films. The films were deposited on different substrates: Mo and ITO coated glass. The optimum potentials for electrodeposition of CISe and CIGSe films were respectively selected in the range -400 to -550 mV and -650 to -700 mV (vs. SCE). The electrodeposited layers were firmly adhesive. The well known chalcopyrite structure appears after annealing at 400 degrees C under Argon for CISe. The band gap value deduced from the optical measurements is close to 1 eV. To increase this value, addition of gallium in the aqueous electrolytic solution was performed. A band gap value as high as 1.26 eV was recorded on the obtained CIGSe films. Sulfurisation of CISe layers under 5% H2S/Ar atmosphere lead to a shift of the position of the principal XRD peaks indicating the substitution of selenium atoms by sulfur atoms and thus the formation of the quaternary CISSe. Optical measurements performed on this quaternary compound show that our films exhibit a band gap value scaling from 1 eV to 1.4 eV depending on the amount of sulphur incorporated into the layers during the heat treatments.

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