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1.
Psychol Med ; 46(15): 3137-3149, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27572473

RESUMO

BACKGROUND: Impulsivity is a core feature of borderline personality disorder (BPD) and attention deficit hyperactivity disorder (ADHD). In BPD, impulsive behavior primarily occurs under acute stress; impulse control deficits under non-stress conditions may be partly related to co-morbid ADHD. We aimed to investigate whether acute experimental stress has an impact on self-reported impulsivity, response inhibition (action withholding, action cancelation) and delay discounting in BPD compared to ADHD. METHOD: Thirty female BPD patients, 28 female ADHD patients (excluding patients with co-morbid BPD and ADHD), and 30 female healthy controls (HC) completed self-reports and behavioral measures of impulsivity (IMT, assessing action withholding; GoStop, measuring action cancelation, Delay Discounting Task) under baseline conditions and after an experimental stress induction (Mannheim Multicomponent Stress Test). RESULTS: Both patient groups reported higher impulsivity than HC, ADHD reported higher trait impulsivity than BPD. On the IMT, ADHD showed significant action-withholding deficits under both conditions, while BPD performed significantly worse than HC under stress. In BPD but not ADHD and HC, action-withholding deficits (IMT) were significantly increased under stress compared to baseline, while no group/stress effects were found for action cancelation (GoStop). Delay discounting was significantly more pronounced in BPD than in HC (no stress effect was found). CONCLUSIONS: In BPD, behavioral deficits in action withholding (but not in action cancelation) appear to be influenced by acute experimental stress. Delay discounting seems to be a general feature of BPD, independent of co-morbid ADHD and acute stress, possibly underlying typical expressions of behavioral impulsivity in the disorder.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtorno da Personalidade Borderline/psicologia , Desvalorização pelo Atraso , Inibição Psicológica , Estresse Psicológico/psicologia , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Transtorno da Personalidade Borderline/fisiopatologia , Estudos de Casos e Controles , Feminino , Humanos , Estresse Psicológico/fisiopatologia , Adulto Jovem
2.
Acta Psychiatr Scand ; 134(6): 461-468, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27658720

RESUMO

OBJECTIVE: Electroconvulsive therapy (ECT) is a highly effective and well-tolerated therapy for severe and treatment-resistant depression. Cognitive side-effects are still feared by some patients and clinicians. Importantly, cognitive impairments are among the most disabling symptoms of depression itself. METHODS: Patients suffering from a severe episode of depression were treated with either ECT or treatment as usual (TAU) in an in-patient setting. Matched healthy participants served as controls (HC). Verbal memory was tested with the California Verbal Learning Test (CVLT) before the specific treatment started (ECT = 15, TAU = 16, HC = 31) and 2 months after the last ECT session or 2 months after discharge respectively. RESULTS: Before the specific treatment started, depressed patients performed substantially worse compared with HC in total, short- and long-delay recall in the CVLT, while the ECT group showed the worst performance. More severely depressed patients showed worse performances in these measures. Intriguingly, verbal memory showed a significant improvement in ECT-treated patients, but not in the other groups. No differences between the groups were found at follow-up. CONCLUSION: Contrary to the widely feared assumption that ECT has long-term impact on memory functions, we found evidence that ECT is superior to TAU in improving verbal memory in depressed patients.


Assuntos
Transtorno Depressivo Maior/terapia , Eletroconvulsoterapia/métodos , Transtornos da Memória/terapia , Avaliação de Resultados em Cuidados de Saúde , Adulto , Transtorno Depressivo Maior/complicações , Eletroconvulsoterapia/efeitos adversos , Feminino , Seguimentos , Humanos , Masculino , Transtornos da Memória/etiologia , Pessoa de Meia-Idade , Índice de Gravidade de Doença
3.
Neth Heart J ; 23(6): 348-50, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25896780

RESUMO

Alveolar rhabdomyosarcoma is an aggressive tumour in adulthood, in which cardiac troponin T seems to be a tumour marker and course parameter. We present the clinical course of a young man suffering from this rare disease and the development of troponin T during therapy. Noninvasive cardiac imaging was used to exclude cardiac involvement, myocardial infarction or inflammation processes.

4.
NMR Biomed ; 27(6): 709-15, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24692120

RESUMO

MRI and MRS in small rodents demand very high sensitivity. Cryogenic transmit/receive radiofrequency probes (CryoProbes) designed for (1) H MRI of mouse brain provide an attractive option for increasing the performance of small-animal MR systems. As the Larmor frequency of (13) C nuclei is four times lower than that for (1) H nuclei, an even larger sensitivity improvement is expected for (13) C applications. The aim of this work was to evaluate the performance of a prototype (13) C CryoProbe™ for mouse brain MRS. To investigate the possible gain of the (13) C CryoProbe™, we acquired localized single-voxel (13) C spectra and chemical shift images of a dimethyl sulfoxide phantom with the CryoProbe™, as well as with two room temperature resonators. The cryogenically cooled resonator achieved approximately four-fold higher signal-to-noise ratio in phantom tests when compared with the best-performing room temperature coil. In addition, we present localized (13) C spectra of mouse brain obtained with the CryoProbe™, as well as with one of the room temperature coils, demonstrating the performance in vivo. In summary, the cryogenic cooling technique significantly enhances the (13) C signal sensitivity at 9.4 T and enables the investigation of metabolism within mouse brain.


Assuntos
Encéfalo/metabolismo , Isótopos de Carbono , Espectroscopia de Ressonância Magnética/instrumentação , Razão Sinal-Ruído , Animais , Glucose/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Camundongos , Camundongos Endogâmicos C57BL , Imagens de Fantasmas , Temperatura
5.
Psychol Med ; 44(15): 3329-40, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25065373

RESUMO

BACKGROUND: Previous research on impulsivity in borderline personality disorder (BPD) has revealed inconsistent findings. Impulsive behaviour is often observed during states of emotional distress and might be exaggerated by current attention deficit hyperactivity disorder (ADHD) symptoms in individuals with BPD. We aimed to investigate different components of impulsivity dependent on stress induction controlling for self-reported ADHD symptoms in BPD. METHOD. A total of 31 unmedicated women with BPD and 30 healthy women (healthy controls; HCs), matched for age, education and intelligence, completed self-reports and behavioural tasks measuring response inhibition (go/stop task) and feedback-driven decision making (Iowa Gambling Task) under resting conditions and after experimental stress induction. ADHD symptoms were included as a covariate in the analyses of behavioural impulsivity. Additionally, self-reported emotion-regulation capacities were assessed. RESULTS: BPD patients reported higher impulsive traits than HCs. During stress conditions - compared with resting conditions - self-reported impulsivity was elevated in both groups. Patients with BPD reported higher state impulsivity under both conditions and a significantly stronger stress-dependent increase in state impulsivity. On the behavioural level, BPD patients showed significantly impaired performance on the go/stop task under stress conditions, even when considering ADHD symptoms as a covariate, but not under resting conditions. No group differences on the Iowa Gambling Task were observed. Correlations between impulsivity measures and emotion-regulation capacities were observed in BPD patients. CONCLUSIONS: Findings suggest a significant impact of stress on self-perceived state impulsivity and on response disinhibition (even when considering current ADHD symptoms) in females with BPD.


Assuntos
Transtorno da Personalidade Borderline/fisiopatologia , Comportamento Impulsivo/fisiologia , Inibição Psicológica , Desempenho Psicomotor/fisiologia , Estresse Psicológico/fisiopatologia , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem
6.
Magn Reson Med ; 69(2): 317-20, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22488982

RESUMO

Despite MEGA-PRESS being a robust method for editing the GABA resonance, there are macromolecule resonances at the same chemical shift that are coedited with this sequence. Although this is a known problem, it is still often overlooked. We aimed to evaluate the amount of macromolecule signal coedited, as well as the gender and age dependencies for the GABA resonance at 3.01 ppm using MEGA-PRESS with two different editing pulse frequencies. Forty-five healthy subjects (21-52 years) were included in an in vivo single voxel MEGA-PRESS study at 3.0 T. Phantom measurements were conducted to measure the signal loss when switching the editing pulse between 1.5 and 1.9 ppm instead of the mostly used switching between 1.9 and 7.5 ppm. The in vivo GABA signal detected by switching the editing pulse frequencies between 1.5 and 1.9 ppm was only 50% of the mean GABA detected by switching the editing pulse frequencies between 1.9 and 7.5 ppm. No gender differences were detected. A small age dependency was observed for GABA plus macromolecules, but not for GABA, suggesting an age-dependent macromolecule increase.


Assuntos
Envelhecimento/metabolismo , Algoritmos , Giro do Cíngulo/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Ácido gama-Aminobutírico/metabolismo , Adulto , Feminino , Humanos , Substâncias Macromoleculares/metabolismo , Masculino , Pessoa de Meia-Idade , Neurotransmissores/metabolismo , Prótons , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores Sexuais , Distribuição Tecidual
7.
Int J Cardiol ; 318: 115-120, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32413468

RESUMO

BACKGROUND: In the first three months after Transcatheter aortic valve implantation (TAVI), a remarkable number of patients have an unfavorable outcome. An inflammatory response after TAVI is suspected to have negative effects. The exact mechanisms remain unclear. We examined the influence of monocyte subpopulations on the clinical outcome, along with the degree of monocyte activation and further parameters of inflammation and platelet activation. METHODS: Flow-cytometric quantification analyses of peripheral blood were done in 120 consecutive patients who underwent TAVI (one day before TAVI and on day 1 and 7 after TAVI). Monocyte-subsets were defined by their CD14 and CD16 expression, monocyte-platelet-aggregates (MPA) by CD14/CD41 co-expression. The extent of monocyte activation was determined by quantification of CD11b-expression (activation epitope). Additionally, pro-inflammatory cytokines such as interleukin (IL)-6, IL-8, C-reactive protein were measured with the cytometric bead array method or standard laboratory tests. RESULTS: Elevated Mon2 (CD14++CD16+) - monocytes (38 vs. 62 cells/µl, p < 0.001) and a high expression of CD11b prior to TAVI (MFI 50.1 vs. 84.6, p < 0.05) were independently associated with death 3 months after TAVI. Mon2 showed the highest CD11b-expression and CD11b correlated with platelet activation and markers of systemic inflammation. Even CRP and IL-8 before TAVI were associated with death after TAVI. In contrast, a systemic inflammation response shortly after TAVI was not associated with early death. CONCLUSIONS: Elevated Mon2-monocytes and a high level of monocyte activation before TAVI are associated with early mortality after TAVI. Chronic inflammation in aging patients seems to be an important risk factor after TAVI.


Assuntos
Substituição da Valva Aórtica Transcateter , Valva Aórtica , Biomarcadores , Plaquetas , Humanos , Monócitos , Ativação Plaquetária , Substituição da Valva Aórtica Transcateter/efeitos adversos
8.
Arch Gen Psychiatry ; 57(10): 937-43, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11015811

RESUMO

BACKGROUND: We monitored the effect of electroconvulsive therapy (ECT) on the nuclear magnetic resonance-detectable metabolites N-acetylaspartate, creatine and phosphocreatine, and choline-containing compounds in the hippocampus by means of hydrogen 1 magnetic resonance spectroscopic imaging. We hypothesized that if ECT-induced memory deterioration was associated with neuronal loss in the hippocampus, the N-acetylaspartate signal would decrease after ECT and any increased membrane turnover would result in an increase in the signal from choline-containing compounds. METHODS: Seventeen patients received complete courses of ECT, during which repeated proton magnetic resonance spectroscopic imaging studies of the hippocampal region were performed. Individual changes during the course of ECT were compared with values obtained in 24 healthy control subjects and 6 patients remitted from major depression without ECT. RESULTS: No changes in the hippocampal N-acetylaspartate signals were detected after ECT. A significant mean increase of 16% of the signal from choline-containing compounds after 5 or more ECT treatments was observed. Despite the mostly unilateral ECT application (14 of 17 patients), the increase in the choline-containing compound signal was observed bilaterally. Lactate or elevated lipid signals were not detected. All patients showed clinical amelioration of depression after ECT. CONCLUSIONS: Electroconvulsive therapy is not likely to induce hippocampal atrophy or cell death, which would be reflected by a decrease in the N-acetylaspartate signal. Compared with an age-matched control group, the choline-containing compounds signal in patients with a major depressive episode was significantly lower than normal, before ECT and normalized during ECT.


Assuntos
Ácido Aspártico/análogos & derivados , Eletroconvulsoterapia , Hipocampo/anatomia & histologia , Hipocampo/metabolismo , Espectroscopia de Ressonância Magnética , Adulto , Ácido Aspártico/química , Ácido Aspártico/metabolismo , Morte Celular , Colina/análise , Colina/metabolismo , Creatina/análise , Creatina/metabolismo , Feminino , Hipocampo/química , Humanos , Espectroscopia de Ressonância Magnética/estatística & dados numéricos , Masculino , Transtornos da Memória/diagnóstico , Transtornos da Memória/etiologia , Transtornos da Memória/metabolismo , Pessoa de Meia-Idade , Fosfatidilcolinas/análise , Fosfatidilcolinas/metabolismo , Fosfocreatina/análise , Fosfocreatina/metabolismo
9.
Am J Psychiatry ; 158(8): 1314-6, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11481168

RESUMO

OBJECTIVE: Using proton magnetic resonance spectroscopic imaging, the authors measured thalamic N-acetylaspartate (NAA) concentrations in patients with schizophrenia. METHOD: The study included 15 schizophrenic patients on a stable medication regimen and 15 age-matched healthy comparison subjects. Concentrations of NAA, creatine plus phosphocreatine, and choline-containing compounds in bilateral thalamic regions were determined. RESULTS: Previous findings of lower NAA concentration in the left and right mediodorsal region of the thalamus and significant correlations between left and right thalamic NAA measures in patients with schizophrenia were corroborated. Furthermore, the concentrations of choline-containing compounds were significantly lower in the schizophrenic patients. No group differences in creatine plus phosphocreatine were found. CONCLUSIONS: There is strong evidence for neuronal dysfunction or loss in the mediodorsal region of the thalamus in patients with schizophrenia.


Assuntos
Ácido Aspártico/análise , Esquizofrenia/diagnóstico , Tálamo/química , Adulto , Ácido Aspártico/análogos & derivados , Colina/análise , Feminino , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Espectroscopia de Ressonância Magnética/estatística & dados numéricos , Masculino , Fosfocreatina/análise , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatologia , Tálamo/fisiopatologia
10.
Neurology ; 57(7): 1184-90, 2001 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-11591833

RESUMO

BACKGROUND: The appearance of decreased 2-[(18)F]fluoro-2-deoxy-D-glucose (FDG) uptake in the mesial temporal region in temporal lobe epilepsy may simply reflect loss of gray matter due to hippocampal atrophy. Increased partial volume effects due to atrophic hippocampi may further increase appearance of hypometabolism. METHODS: The authors used a combination of MRI-PET coregistration, with MRI-based gray matter segmentation, and partial volume correction to improve the examination of hippocampal specific glucose uptake in FDG PET. The goal was to determine 1) if relative mesial temporal hypometabolism is an artifact of gray matter (hippocampal) atrophy, 2) whether hippocampal metabolism correlates with atrophy evaluated on MRI, and 3) if MRI-based partial volume correction influences measurement of hippocampal metabolic-volume relationships, including epilepsy lateralization. RESULTS: Findings showed that ipsilateral hippocampi of mesial temporal lobe epilepsy (MTLE) are relatively hypometabolic per unit of gray matter volume, and that hippocampal metabolism directly correlates with hippocampal volume. Specifically, partial volume corrected hippocampal metabolism correlated strongly (r = 0.613, p < 0.001) with hippocampal volume. Without partial volume correction, a weaker, but still significant, correlation was present (r = 0.482, p < 0.001). Degree of asymmetry was consistently greater and provided higher sensitivity of lateralization with partial volume vs non-partial volume corrected metabolic measurements. CONCLUSIONS: Although, decreased metabolism may occur in the absence of neuronal cell loss, hippocampal atrophy and presumed degree of neuronal cell loss appears to be a primary factor involved in the cause of decreased metabolism in epileptogenic hippocampi. Partial volume correction is recommended for optimal interpretation of hippocampal structure and function relationships.


Assuntos
Epilepsia do Lobo Temporal/metabolismo , Glucose/metabolismo , Hipocampo/metabolismo , Adolescente , Adulto , Atrofia , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/patologia , Feminino , Fluordesoxiglucose F18 , Lateralidade Funcional , Hipocampo/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão
11.
Neurology ; 59(4): 633-6, 2002 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-12196667

RESUMO

(1)H MRS imaging was obtained from 10 patients with mesial temporal lobe epilepsy before and after surgery. After surgery, metabolic recovery in the contralateral hippocampus was detected. Preoperatively, reduced N-acetylaspartate (p < 0.04) increased after surgery nonsignificantly to equal control values. Cholines increased after surgery (p < 0.02) and creatine-phosphocreatine showed a trend to higher values. The results suggest that the contralateral hippocampus is affected by repeated seizure activity in the ipsilateral hippocampus, rather than presence of bilateral mesial temporal sclerosis.


Assuntos
Ácido Aspártico/análogos & derivados , Epilepsia do Lobo Temporal/cirurgia , Hipocampo/metabolismo , Espectroscopia de Ressonância Magnética , Procedimentos Neurocirúrgicos , Recuperação de Função Fisiológica , Adulto , Ácido Aspártico/análise , Ácido Aspártico/metabolismo , Colina/análise , Colina/metabolismo , Creatina/análise , Creatina/metabolismo , Feminino , Lateralidade Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Fosfocreatina/análise , Fosfocreatina/metabolismo , Prótons , Valores de Referência , Resultado do Tratamento , Água/análise , Água/metabolismo
12.
Schizophr Res ; 41(3): 389-95, 2000 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-10728716

RESUMO

The authors performed a MRSI study of the anterior cingulate gyrus in 19 schizophrenic patients under stable medication and 16 controls in order to corroborate previous findings of reduced NAA in the anterior cingulate region in schizophrenia. Furthermore, correlations between NAA in the anterior cingulate gyrus and age or illness duration have been determined. A decreased NAA signal was found in the anterior cingulate gyrus of patients compared to controls. Subdividing the patient group into two groups depending on medication revealed that the group of patients receiving a typical neuroleptic medication showed a lower mean NAA in comparison to the group of patients receiving atypical antipsychotic drugs. No significant group differences in the creatine and phosphocreatine signal or the signal from choline-containing compounds were found. The NAA signal significantly correlated with age, and therefore, individual NAA values were corrected for the age effect found in the control group. The age-corrected NAA signal in schizophrenia correlated significantly with the duration of illness. The detected correlations of NAA decrease with age and illness duration are consistent with recent imaging studies where progressing cortical atrophy in schizophrenia was found. Further studies will be needed to corroborate a possible favorable effect of atypical antipsychotics on the NAA signal.


Assuntos
Antipsicóticos/administração & dosagem , Ácido Aspártico/análogos & derivados , Giro do Cíngulo/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Esquizofrenia/tratamento farmacológico , Adulto , Antipsicóticos/efeitos adversos , Ácido Aspártico/metabolismo , Doença Crônica , Clozapina/efeitos adversos , Clozapina/uso terapêutico , Creatina/metabolismo , Feminino , Giro do Cíngulo/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Fosfocreatina/metabolismo , Valores de Referência , Risperidona/efeitos adversos , Risperidona/uso terapêutico , Esquizofrenia/fisiopatologia , Resultado do Tratamento
13.
Schizophr Res ; 39(1): 19-29, 1999 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-10480664

RESUMO

Brain function and laterality in schizophrenia were investigated by means of a simple motor task with a self-generated left-hand sequential finger opposition (SFO) using a whole-brain high-speed (100 ms per slice) functional imaging technique. Neuroleptic-naïve, acutely ill schizophrenic patients were compared to schizophrenic patients under stable neuroleptic medication and matched controls. The goal was to evaluate both the motor function in first-episode patients and possible effects of different neuroleptic treatments on functional MRI results. Forty patients satisfying ICD 10 criteria (F20.x) for schizophrenia and sex- and age-matched healthy volunteers participated in this study. All subjects underwent fMRI examinations on a conventional 1.5 T MR unit. The primary sensorimotor cortex and the high-order supplementary motor area (SMA) were evaluated. There was a close similarity in the activation of the primary and high-order (SMA) sensorimotor areas between first-episode schizophrenic patients and controls. In contrast, a significant reduction in the overall blood oxygen level dependent (BOLD) response was seen in sensorimotor cortices (contra- and ipsilateral) in schizophrenic patients under stable medication with typical neuroleptics. This effect was not present in patients treated with atypical antipsychotics. Both antipsychotic treatments, however, led to a significant reduction in activation of the SMA region compared to controls and neuroleptic-naïve subjects. Thus, the present study provides no evidence for the localized involvement of the primary motor cortex or the SMA as a relatively stable vulnerability marker in schizophrenia. There is, however, strong evidence that neuroleptics themselves influence fMRI activation patterns and that there are major differences between typical neuroleptics and atypical antipsychotics.


Assuntos
Antipsicóticos/efeitos adversos , Clozapina/efeitos adversos , Córtex Motor/anatomia & histologia , Córtex Motor/efeitos dos fármacos , Desempenho Psicomotor/efeitos dos fármacos , Risperidona/efeitos adversos , Esquizofrenia/tratamento farmacológico , Córtex Somatossensorial/anatomia & histologia , Córtex Somatossensorial/efeitos dos fármacos , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Motor/fisiopatologia , Oxigênio/sangue , Esquizofrenia/diagnóstico , Esquizofrenia/fisiopatologia , Córtex Somatossensorial/fisiopatologia
14.
Science ; 197(4299): 151-2, 1977 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-17834080
15.
Phys Med Biol ; 37(1): 261-71, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1741428

RESUMO

Image correlation methods enable the complementary use of information from different medical images of a patient. These images can be obtained from different imaging devices (CT, MR, PET), or, from one imaging device taken at different times. Unfortunately, there are few cases in which the requirements for later image correlation are taken into account at the time of image acquisition. There is therefore a need for correlation techniques requiring no preparation in advance. We have developed two correlation methods, both based on three or more anatomical or artificial landmarks, to be defined in corresponding image data sets. These methods have been evaluated with phantom data as well as with patient data. We have improved these correlation methods by using more landmarks and special selection criteria. They are applicable to all medical tomograms and to x-ray pictures taken under stereotactical conditions. The results obtained have error ranges in the order of the three-dimensional image resolution.


Assuntos
Diagnóstico por Imagem/métodos , Estudos de Avaliação como Assunto , Humanos , Imageamento por Ressonância Magnética , Modelos Estruturais , Tomografia Computadorizada de Emissão , Tomografia Computadorizada por Raios X
16.
J Infect ; 13(1): 25-30, 1986 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3734463

RESUMO

Over a period of 3 months during the summer, 362 African children admitted to King Edward VIII Hospital, Durban, were screened for the faecal excretion of Cryptosporidium oocysts. Of 259 children with diarrhoea, oocysts were detected in 31 (11.9%), while none was found in the faeces of 103 children without diarrhoea (controls). All those children excreting Cryptosporidium were under 2 years of age, giving a prevalence of 15% for this group. Other potential enteric pathogens were detected in the faeces of 12 (38.7%) of these children. The case fatality rate for patients with Cryptosporidium was 22.6%, which may reflect the selection of patients in a study concentrating on hospital inpatients. Cryptosporidium was the second most common organism detected in diarrhoeal faeces, and the only one detected in 9.2% of diarrhoeal children aged less than two years. These findings indicate that Cryptosporidium should be regarded as a potential pathogen in children admitted to this hospital with severe diarrhoea. Such association of Cryptosporidium with diarrhoea in children accords with recent studies in other parts of the world.


Assuntos
Criptosporidiose/epidemiologia , Diarreia/parasitologia , Enteropatias Parasitárias/epidemiologia , Fatores Etários , População Negra , Criança , Pré-Escolar , Criptosporidiose/mortalidade , Diarreia/epidemiologia , Fezes/parasitologia , Feminino , Humanos , Lactente , Masculino , África do Sul
17.
Psychiatry Res ; 98(3): 145-54, 2000 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10821997

RESUMO

The purpose of the present study was to evaluate the cortical response to motor stimulation in neuroleptic-naive first episode schizophrenics in comparison to matched controls using a high speed functional magnetic resonance imaging technique (fMRI). Twelve patients satisfying ICD 10 criteria (F20.0) for schizophrenia (paranoid subtype) as well as sex- and age-matched healthy volunteers participated in this study. All subjects underwent fMRI examination on a conventional 1.5 T MR unit equipped with an echo-planar imaging booster. The blood oxygen level dependent (BOLD) response of the sensorimotor cortex and the higher order SMA region was evaluated during performance of a left hand sequential finger opposition task. Special care was taken to minimize performance and motion artifacts. Patients and controls showed no notable difference with respect to laterality, changes of signal intensity or spatial extent of activation within the primary and higher order motor regions. Using high speed fMRI no fundamental motor cortical dysfunction was evident in a group of paranoid neuroleptic-naive first episode schizophrenic patients. In contrast to data previously reported for chronic disorganized medicated patients, these results suggest that motor dysfunction is not part of the phenomenology of acute paranoid first episode patients.


Assuntos
Imagem Ecoplanar , Córtex Motor/patologia , Destreza Motora , Esquizofrenia Paranoide/patologia , Doença Aguda , Adulto , Estudos de Casos e Controles , Dominância Cerebral , Feminino , Humanos , Masculino , Córtex Motor/fisiopatologia , Esquizofrenia Paranoide/fisiopatologia
18.
Rofo ; 170(6): 568-74, 1999 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-10420907

RESUMO

PURPOSE: 31P MR spectroscopic imaging (31P SI) was evaluated in a clinical study as a method for monitoring presurgical devascularization of meningiomas. The aim was to assess noninvasively metabolic alterations in tumor and in healthy brain tissue before and after embolization. METHODS: Localized 31P MR spectra of the brain were obtained by means of 2D-SI (voxel size: 36 cm3) using a 1,5-T whole-body MR tomograph. RESULTS: Eleven of 19 patients with intracranial meningiomas examined in this study underwent preoperative embolization therapy; eight patients were examined before and after treatment. After embolization, alterations of pH and of the concentrations of high-energy phosphates (nucleoside-5' triphosphate = NTP, phosphocreatine = PCr), inorganic phosphate (Pi), and membrane constituents were observed in the tumors. A tendency of [Pi] increase and decrease of [NTP], [PCr], and pH predominated, which is explained by ischemic processes after tumor devascularization. CONCLUSION: 31P SI is applicable in clinical studies and detects alterations of phosphate metabolism in a meningioma after embolization.


Assuntos
Embolização Terapêutica , Metabolismo Energético/fisiologia , Espectroscopia de Ressonância Magnética , Neoplasias Meníngeas/irrigação sanguínea , Meningioma/irrigação sanguínea , Adulto , Idoso , Encéfalo/irrigação sanguínea , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Pessoa de Meia-Idade , Fosfatos/metabolismo , Cuidados Pré-Operatórios
19.
Neurology ; 72(20): 1735-40, 2009 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-19451528

RESUMO

OBJECTIVE: The need for biological markers of Alzheimer disease (AD) is constantly increasing. Proton magnetic resonance spectroscopy ((1)H-MRS) studies have provided consistent evidence for a reduction of the neuronal marker N-acetylaspartate (NAA) in patients with AD. Within the German Competence Network on Dementia, we conducted a (1)H-MRS study in patients with mild dementia and mild cognitive impairment (MCI) at four sites to investigate the multicenter feasibility of (1)H-MRS. METHODS: In total, 130 patients with dementia (98 AD, 32 non-AD), 136 subjects with MCI (70 of AD type, 66 of non-AD type), and 45 unimpaired control subjects were included. Single-volume (1)H-MRS of the left medial temporal lobe was performed at long and short echo times. Metabolites were quantified and metabolic ratios were determined. RESULTS: We found a significant reduction of NAA concentration in patients with AD as compared to healthy volunteers and compared to patients with MCI of AD type. NAA/Cr (creatine/phosphocreatine) was also lower in patients with AD compared to control subjects. NAA, choline compounds, and Cr were lower in patients with AD compared to patients with non-AD dementia. CONCLUSIONS: We demonstrated the multicenter feasibility of proton magnetic resonance spectroscopy ((1)H-MRS) of the medial temporal lobe in mild dementia and mild cognitive impairment, which is a prerequisite for the application of (1)H-MRS in large-scale clinical trials. Since the concentration measures of the metabolites are adjusted for brain tissue volume, these findings are indicators of biochemical pathology beyond brain atrophy.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/patologia , Espectroscopia de Ressonância Magnética/métodos , Lobo Temporal/patologia , Idoso , Doença de Alzheimer/diagnóstico , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Biomarcadores/metabolismo , Transtornos Cognitivos/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Lobo Temporal/anatomia & histologia , Lobo Temporal/metabolismo
20.
Magn Reson Med ; 57(4): 784-90, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17390361

RESUMO

Echo-planar spectroscopic imaging (EPSI) is one of the fastest spectroscopic imaging (SI) methods. It has been applied to (1)H MR spectroscopy (MRS) studies of the human brain in vivo. However, to our knowledge, EPSI with detection of the (31)P nucleus to monitor phosphorus-containing neurometabolites has not yet been considered. In this work, eight different (31)P-{(1)H} EPSI sequence versions with spectral widths ranging from 313 Hz to 2.27 kHz were implemented on a clinical 1.5T whole-body MR tomograph. The sequence versions utilized the heteronuclear nuclear Overhauser effect (NOE) for (31)P signal enhancement. The sensitivity observed in experiments with model solutions was in good agreement with theoretical predictions. In vivo measurements performed on healthy volunteers (N = 16) demonstrated the feasibility of performing two-dimensional (2D) (31)P-{(1)H} EPSI in the human brain, and the technique enabled fast acquisition of well-resolved localized spectra.


Assuntos
Química Encefálica , Imagem Ecoplanar/métodos , Espectroscopia de Ressonância Magnética/métodos , Fosfatos/metabolismo , Trifosfato de Adenosina/metabolismo , Algoritmos , Estudos de Viabilidade , Humanos , Imagens de Fantasmas , Isótopos de Fósforo , Processamento de Sinais Assistido por Computador
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