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1.
Epilepsy Behav ; 25(1): 120-4, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22841424

RESUMO

The increasing demand for clinical fMRI data has resulted in a need to translate research methods to clinical use. Referrals for language lateralization prior to epilepsy surgery are becoming more common, but time constraints make this unachievable in many busy neuroimaging departments. This study examines whether a single covert verbal fluency paradigm with real-time monitoring and online processing (BrainWave) could replace conventional offline processing (SPM) for the purpose of establishing expressive language dominance prior to epilepsy surgery. We analyzed language fMRI results of 30 patients (17 female; 24 right-handed; median age: 30.5) with temporal lobe epilepsy. Concordance between visual assessment of SPM and BrainWave was 92.8%. Lateralization indices correlated closely with visual assessments of lateralization with a concordance of 85.7%. BrainWave provided a real-time, fast and accurate display of language lateralization easily applied in a clinical setting using only online image processing.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/irrigação sanguínea , Epilepsia do Lobo Temporal/patologia , Idioma , Sistemas On-Line , Comportamento Verbal/fisiologia , Adolescente , Adulto , Ondas Encefálicas/fisiologia , Epilepsia do Lobo Temporal/cirurgia , Feminino , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Adulto Jovem
2.
Neuroimage ; 46(3): 749-61, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19236922

RESUMO

The segmentation from MRI of macroscopically ill-defined and highly variable structures, such as the hippocampus (Hc) and the amygdala (Am), requires the use of specific constraints. Here, we describe and evaluate a fast fully automatic hybrid segmentation that uses knowledge derived from probabilistic atlases and anatomical landmarks, adapted from a semi-automatic method. The algorithm was designed at the outset for application on images from healthy subjects and patients with hippocampal sclerosis. Probabilistic atlases were built from 16 healthy subjects, registered using SPM5. Local mismatch in the atlas registration step was automatically detected and corrected. Quantitative evaluation with respect to manual segmentations was performed on the 16 young subjects, with a leave-one-out strategy, a mixed cohort of 8 controls and 15 patients with epilepsy with variable degrees of hippocampal sclerosis, and 8 healthy subjects acquired on a 3 T scanner. Seven performance indices were computed, among which error on volumes RV and Dice overlap K. The method proved to be fast, robust and accurate. For Hc, results with the new method were: 16 young subjects {RV=5%, K=87%}; mixed cohort {RV=8%, K=84%}; 3 T cohort {RV=9%, K=85%}. Results were better than with atlas-based (thresholded probability map) or semi-automatic segmentations. Atlas mismatch detection and correction proved efficient for the most sclerotic Hc. For Am, results were: 16 young controls {RV=7%, K=85%}; mixed cohort {RV=19%, K=78%}; 3 T cohort {RV=10%, K=77%}. Results were better than with the semi-automatic segmentation, and were also better than atlas-based segmentations for the 16 young subjects.


Assuntos
Tonsila do Cerebelo/anatomia & histologia , Inteligência Artificial , Hipocampo/anatomia & histologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Reconhecimento Automatizado de Padrão/métodos , Adulto , Algoritmos , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Acta Radiol ; 47(10): 1067-72, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17135010

RESUMO

PURPOSE: To compare automatic software-based co-registration of serial magnetic resonance imaging (MRI) scans with conventional visual comparison, by expert neuroradiologists. MATERIAL AND METHODS: Sixty-four patients who were referred to our epilepsy MRI unit for cerebral imaging were identified as having potentially, non-, or slow-growing lesions or cerebral atrophy and followed with sequential scans over a period of up to 8 years, resulting in a total of 92 pairs of scans. Scans were categorized as showing either lesions or atrophy. Each pair of scans was reviewed twice for the presence of change, with and without co-registration, performed using automated software. RESULTS: Co-registration and visual reporting without co-registration were discordant in the lesions group in nine out of 69 datasets (13%), and in 16 out of 23 pairs of scans in the atrophy group (69%). The most common cause of discordance was visual reporting not detecting changes apparent by co-registration. In three cases, changes detected visually were not detected following co-registration. CONCLUSION: In the group of patients studied, co-registration was more sensitive for detecting changes than visual comparison, particularly with respect to atrophic changes of the brain. With the increasing availability of sophisticated independent consoles attached to MRI scanners that may be used for image co-registration, we propose that serial T1-weighted volumetric MRI brain co-registration should be considered for integration into routine clinical practice to assess patients with suspected progressive disease.


Assuntos
Encéfalo/patologia , Epilepsia/patologia , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Atrofia , Competência Clínica , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
Addict Biol ; 6(2): 177-181, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11341858

RESUMO

Since the early 1990s ring-substituted derivatives of amphetamine have been abused widely in the Republic of Ireland. The main ring-substituted amphetamines being abused include methylenedioxyamphetamine (MDA), methylenedioxymethamphetamine (MDMA) and methylenedioxyethamphetamine (MDEA). A newer illicit synthetic analogue, which has been seized to a lesser extent by Irish police, is N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MBDB). The work presented here involved the determination of the type of ring-substituted amphetamines being abused by a group of recovering opiate abusers participating in a methadone maintenance programme in a Dublin Drug Rehabilitation Centre. Urine samples which tested positive for amphetamines and ring-substituted amphetamines via EMIT immunoassay were subjected to further analysis using GC-MS with MBTFA flash derivatization. It was found that the methylenedioxypropanamines were being abused, as was amphetamine itself. However, no abuse of methylenedioxybutanamines or thioamphetamines was observed.

6.
Addict Biol ; 4(1): 81-7, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20575774

RESUMO

Five commercially available immunoassay test kits (SYVA EMIT(R) d.a.u(TM), SYVA EMIT(R) II assay, Abbott FPIA, Cozart Auto-Lyte(R) and Roche Abuscreen(R) Online(TM), all used for the benzodiazepine group of drugs) were evaluated for their ability to detect flunitrazepam, its major urinary metabolite, 7-aminoflunitrazepam, and several other benzodiazepines at serial dilutions (final concentration 25-1000 ng/ml) in drug-free urine and in urines following oral administration of flunitrazepam (1-3 mg). For comparison, gas chromatography/mass spectrometry was used to measure urinary levels of 7-aminoflunitrazepam. Levels of drug detected in the study were compared with the cross-reactivities presented by the manufacturers for each individual kit. One to three mg doses of flunitrazepam were taken by volunteers and levels excreted in urine analysed over several hours. A positive response was obtained in several samples from volunteers who had taken 2 mg or 3 mg doses, but not a 1 mg dose. Thirty-five clinical samples from the individuals suspected of benzodiazepine abuse were also examined. The results were not consistent among the kits evaluated.We conclude that the test kits evaluated in this study do not detect flunitrazepam reliably, due primarily to their poor sensitivities.

7.
J Steroid Biochem ; 28(5): 565-9, 1987 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3682822

RESUMO

[3H]Dihydrotestosterone (50 microCi) was infused into normal men and women for 8 h. It was previously shown that this was sufficient time for this material to reach a steady state. Venous plasma was obtained at 6 and 8 h, pooled, and the unconjugated steroids removed by ether extraction. The remaining plasma was adjusted to pH 4.9 and the steroid conjugate was extracted first with ethyl acetate and then with an ether-ethanol mixture. The extracts were combined and taken to dryness. Steroid sulfates were solvolyzed using dioxane, and the mixture partitioned between ether and 1% NaOH. The aqueous phase was acidified and added to an XAD-2 column, washed with water, and the glucuronide fraction eluted with methanol. The solvent was concentrated and the methanol extract was passed through a C18 Sep-Pak, filtered through an Acrodisc CR and then subjected to gradient high performance liquid chromatography [HPLC] (Nova-Pak C18, KH2PO4, pH 3, and methanol). The fractions containing steroid glucuronides were collected and esterified with diazomethane and then acetylated with acetic anhydride in pyridine. The glucuronide triacetyl methyl ester (GAME) derivatives were then run in a second HPLC system (3 Lichrosorb 5 mu columns, 4 mm x 25 cm) using a gradient of ethanol-heptane and heptane. We clearly established that this system separates 3 alpha-diol GAME conjugated at the 17 and 3 positions (44 vs 50 min) with authentic samples previously synthesized in our laboratory. We concluded that the pooled plasma contained only the 17-GAME conjugate. No significant activity of the 3-glucuronide was detected. The natural compound in circulation, therefore, is 5 alpha-androstane-3 alpha, 17 beta-diol 17-glucuronide.


Assuntos
Androstano-3,17-diol/sangue , Androstanóis/sangue , Androstano-3,17-diol/análogos & derivados , Androstano-3,17-diol/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Di-Hidrotestosterona/metabolismo , Feminino , Humanos , Masculino , Trítio
8.
Int J Pept Protein Res ; 29(1): 118-25, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3570651

RESUMO

The DL-arylamino acid ethyl ester derivatives of beta-(3-pyridyl)-DL-alanine, and beta-(3-benzo[b]thienyl)-DL-alanine were synthesized by diethyl acetamidomalonate condensation with the respective arylmethyl halides followed by partial hydrolysis to the monoethyl ester and decarboxylation. Each derivative was enzymatically resolved to a separable mixture of the corresponding N-acetyl-L-amino acid and the unchanged D amino acid derivative. Acidic hydrolysis of the latter gave the corresponding D-amino acid, the optical purity of which was established by HPLC analysis of the 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl isothiocyanate (GITC) derivative. The free D amino acids were converted to D-BOC derivatives by reaction with di-tert-butyldicarbonate in tert-butyl alcohol, water and sodium hydroxide.


Assuntos
Alanina/análogos & derivados , Alanina/síntese química , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Espectrofotometria Infravermelho
10.
Regul Pept ; 8(3): 177-87, 1984 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6611566

RESUMO

Pancreatic polypeptide (PP) immunoreactivity in acid-ethanol extracts of the pancreas of representative species of mammals, birds, reptiles, amphibians, and fish was studied by a radioimmunoassay (RIA) that utilizes an antiserum which cross-reacts exclusively with the COOH-terminal hexapeptide of PP (CTPP). PP immunoreactivity in acid-ethanol extracts of rat nonpancreas tissues (stomach, duodenum, skeletal muscle, brain) was also examined. Significant concentrations of PP immunoreactivity were detected in the pancreatic extracts of all species, except fish. Appreciable quantities of PP immunoreactivity were also found in the stomach and duodenum of rats. In all cases, tissue extracts showed parallelism with reference PP (bovine) in the RIA. Gel chromatography (Sephadex G-50sf) of tissue extracts (rat, turtle) demonstrated a major peak of PP immunoreactivity, which eluted in the region of the reference PP. Salamander PP immunoreactivity eluted after bovine PP. In addition, the CTPP RIA can be applied to measure plasma levels of PP in rats, dogs, and humans. By using this PP RIA, we observed that plasma PP levels increase significantly in dogs (P less than 0.05) after intravenous administration of neurotensin. In rats, administration of intravenous bombesin resulted in a significant elevation of plasma PP.


Assuntos
Polipeptídeo Pancreático/análise , Animais , Galinhas , Cães , Duodeno/análise , Peixes , Humanos , Soros Imunes , Lagartos , Necturus , Pâncreas/análise , Polipeptídeo Pancreático/imunologia , Fragmentos de Peptídeos/imunologia , Radioimunoensaio/métodos , Rana pipiens , Ratos , Especificidade da Espécie , Estômago/análise , Distribuição Tecidual , Tartarugas
11.
Steroids ; 42(4): 401-8, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6689617

RESUMO

10 beta-Hydroperoxy-7 alpha-methylnorethindrone 17-heptanoate (II), a product of allylic autoxidation of 7 alpha-methylnorethindrone enanthate (I), has been isolated and characterized. The synthesis of the hydroperoxide (II) from the 3-ethylene ketal of 7 alpha-methylnorethynodrel (III) was achieved. Esterification of alcohol (III), subsequent deketalization, and photochemical oxygenation resulted in the hydroperoxide (II). Reduction of the hydroperoxide (II) to the 10 beta-alcohol (VI) and acetylation of (II) to the 10 beta-acetoxyperoxide (VII) are described. A single subcutaneous injection of the compounds (II), (VI), and (VII) to rats failed to produce long term inhibition of fertility in contrast to the parent compound (I) which is at least five times more effective than norethindrone enanthate as measured by suppression of vaginal cornification and estrous cycles.


Assuntos
Noretindrona/análogos & derivados , Progestinas/síntese química , Animais , Fenômenos Químicos , Química , Estro/efeitos dos fármacos , Feminino , Noretindrona/síntese química , Noretindrona/farmacologia , Oxirredução , Gravidez , Progestinas/farmacologia , Ratos , Vagina/efeitos dos fármacos
12.
Australas Nurses J ; 9(10): 15, 19, 1980 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6905735
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