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CONTEXT: To evaluate the efficacy of diffusion fiber tractography (DFT) and voxel-based morphometry (VBM) for lateralizing language in comparison with functional magnetic resonance imaging (fMRI) to noninvasively assess hemispheric language lateralization in normal healthy volunteers. AIMS: The aim of the present study is to evaluate the concordance of language lateralization obtained by diffusion tensor imaging (DTI) and VBM to fMRI, and thus to see whether there exists an anatomical correlate for language lateralization result obtained using fMRI. SETTINGS AND DESIGN: This is an advanced neuroimaging study conducted in normal healthy volunteers. SUBJECTS AND METHODS: Fifty-seven normal healthy subjects (39 males and 18 females; age range: 15-40 years) underwent language fMRI and 30 underwent direction DTI. fMRI language laterality index (LI), fiber tract asymmetry index (AI), and tract-based statistics of dorsal and ventral language pathways were calculated. The combined results were correlated with VBM-based volumetry of Heschl's gyrus (HG), planum temporale (PT), and insula for lateralization of language function. STATISTICAL ANALYSIS USED: A linear regression analysis was done to study the correlation between fMRI, DTI, and VBM measurements. RESULTS: A good agreement was found between language fMRI LI and fiber tract AI, more specifically for arcuate fasciculus (ArcF) and inferior longitudinal fasciculus (ILF). The study demonstrated significant correlations (P < 0.05) between blood-oxygen-level dependent (BOLD) fMRI activations, tract-based statistics, and PT and HG volumetry for determining language lateralization. CONCLUSIONS: A strong one-to-one correlation between fMRI, laterality index, DTI tractography measures, and VBM-based volumetry measures for determining language lateralization exists.
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Encéfalo/fisiologia , Lateralidade Funcional , Idioma , Adolescente , Adulto , Encéfalo/anatomia & histologia , Imagem de Tensor de Difusão , Feminino , Voluntários Saudáveis , Humanos , Imageamento por Ressonância Magnética , MasculinoRESUMO
This work describes a new well-defined, air-stable, phosphine free palladium(II) [Pd(L)Cl] (1) catalyst. This catalyst was utilized for N-alkylation of amines and indole synthesis where H2O was found to be the by-product. A broad range of aromatic amines were alkylated using this homogeneous catalyst with a catalyst loading of 0.1 mol%. Greener aromatic and aliphatic primary alcohols were utilized and a hydrogen auto-transfer strategy via a metal-ligand cooperative approach was investigated. The precursor of the antihistamine-containing drug molecule tripelennamine was synthesized on a gram scale for large-scale applicability of the current synthetic methodology. A number of control experiments were performed to investigate the possible reaction pathway and the outcomes of these experiments indicated the azo-chromophore as a hydrogen reservoir during the catalytic cycle.
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Hydatidiform mole is an abnormal pregnancy common in Asian populations compared to western countries; however, a partial hydatidiform mole is relatively uncommon and very challenging to diagnose on ultrasound. We reported a 24 years old female visited our clinic whose first antenatal visit was regular with normal viable fetus on ultrasonographic scan. However, an uneventful scan at 12 weeks period of gestation revealed a large irregular gestational sac with the disproportionately small embryo corresponding to 6+6 weeks with no cardiac activity. Additionally, there was markedly thickened placenta measuring 30mm in thickness without cystic spaces within the placenta. Further, her beta-human chorionic gonadotrophin level was very high and suction evacuation sample showed hydropic chorionic villi lined by trophoblastic cells with cistern formation and scalloped border. In conclusion, partial hydatidiform mole is an uncommon molar pregnancy rarely diagnose on ultrasonography. Late first-trimester scan and excessively high beta-human chorionic gonadotrophin levels confirm the diagnosis. Keywords: Hydatidiform mole; molar pregnancy; partial hydatidiform mole.
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Mola Hidatiforme , Ultrassonografia Pré-Natal , Neoplasias Uterinas , Gonadotropina Coriônica Humana Subunidade beta/sangue , Feminino , Humanos , Mola Hidatiforme/diagnóstico por imagem , Placenta , Gravidez , Neoplasias Uterinas/diagnóstico por imagem , Adulto JovemRESUMO
Copper(i) complexes [Cu(L1-7)2](ClO4) (1-7) of bidentate ligands (L1-L7) have been synthesized via spontaneous reduction and characterized as catalysts for aromatic C-H activation using H2O2 as the oxidant. The single crystal X-ray structure of 1 exhibited a distorted tetrahedral geometry. All the copper(i) complexes catalyzed direct hydroxylation of benzene to form phenol with good selectivity up to 98%. The determined kinetic isotope effect (KIE) values, 1.69-1.71, support the involvement of a radical type mechanism. The isotope-labeling experiments using H218O2 showed 92% incorporation of 18O into phenol and confirm that H2O2 is the key oxygen supplier. Overall, the catalytic efficiencies of the complexes are strongly influenced by the electronic and steric factor of the ligand, which is fine-tuned by the ligand architecture. The benzene hydroxylation reaction possibly proceeded via a radical mechanism, which was confirmed by the addition of radical scavengers (TEMPO) to the catalytic reaction that showed a reduction in phenol formation.
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PURPOSE: To assess visual associative learning and famous face recognition ability among subjects with stable amnestic mild cognitive impairment (MCI) relative to early stage dementia due to Alzheimer's disease (AD) and cognitively normal healthy controls (NC) and to correlate these differences with volumetric changes on MRI. METHODS: A hospital-based cross-sectional observational study was conducted on 61 participants. The subjects underwent neuropsychological evaluation, including validated newly designed tests for novel face-name paired association learning recall and famous face recognition. MRI volumetry was done on a subset of patients to ascertain the topographical patterns of volume loss. RESULTS: There were significant differences in performance on free recall for face-name paired associate learning in MCI (n = 22) compared to NC (n = 20) (p < 0.001) and MCI compared to AD (n = 19; p < 0.001). Significant differences were also noted in scores on the famous personalities test between MCI and NC (p = 0.007), and MCI and AD (p = 0.032). The free recall component of face-name pair associative learning significantly correlated with left cuneus (p = 0.005; r = 0.833) and right cuneus (p = 0.003; r = 0.861) volume in AD with no significant correlation among MCI and NC cohorts. CONCLUSIONS: Novel and semantically familiar face-name associative recalls are significantly impaired in MCI, and these potentially predate the MRI volumetric changes in MCI. Our findings expand the spectrum of recall deficits in MCI.