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1.
Sci Rep ; 10(1): 19445, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33173086

RESUMO

Using histogram analysis of T2 values to detect early involvement of extraocular muscles (EOMs) in patients with thyroid-associated ophthalmopathy (TAO). Five EOMs of each orbit were analyzed for 45 TAO patients and 22 healthy controls (HCs). Patients' EOMs were grouped into involved or normal-appearing EOMs (NAEOMs). Histogram parameters and signal intensity ratios (SIRs) of EOMs were compared; receiver operating characteristic (ROC) curve analysis was performed to differentiate NAEOMs from EOMs of HCs. 24 patients were reassessed following immunosuppressive treatment. For SIRs, involved muscles showed higher values than those of NAEOMs and HCs (p < 0.05); there were no differences between NAEOMs and HCs (p = 0.26). Parameters of involved muscles showed no different from those of NAEOMs excluding 25th, 50th percentiles, and standard deviation (SD) (p < 0.05). NAEOMs displayed higher values of 90th, 95th percentiles, SD, skewness, inhomogeneity, and entropy than HCs (p < 0.05). ROC curve analysis of entropy yielded the best area under the ROC curve (AUC; 0.816) for differentiating NAEOMs and HCs. After treatment, histogram parameters including 5th, 75th, 90th, and 95th percentiles, SD, kurtosis, inhomogeneity, and entropy were reduced in NAEOMs (p < 0.05). T2 histogram analysis could detect early involvement of EOMs in TAO prior to detection on conventional orbital MRI.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Oftalmopatia de Graves/diagnóstico , Interpretação de Imagem Assistida por Computador/métodos , Músculos Oculomotores/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos
2.
Addict Biol ; 22(4): 1057-1067, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26969418

RESUMO

Models of heroin addiction emphasize the role of disrupted frontostriatal circuitry supporting cognitive control processes. However, heroin addiction-related alterations in functional and structural interactions among brain regions, especially between the cerebral hemispheres, are rarely examined directly. Resting-state functional magnetic resonance imaging (fMRI) approaches, which reveal patterns of coherent spontaneous fluctuations in the fMRI signal, offer a means to quantify directly functional interactions between the hemispheres. The corpus callosum (CC), which connects homologous regions of the cortex, is the major conduit for information transfer between the cerebral hemispheres and represents a structural connectivity index between hemispheres. We compared interhemispheric voxel-mirrored homotopic connectivity (VMHC) and CC volume between 45 heroin dependent-individuals (HDIs) and 35 non-addict individuals. We observed significant reduction of VMHC in a number of regions, particularly the striatum/limbic system regions, and significant decrease in splenium and genu sub-regions of CC in HDI. Importantly, within HDI, VMHC in the dorsal lateral prefrontal cortex (DLPFC) correlated with genu CC volume, VMHC in the putamen, VMHC in the DLPFC and genu CC volume and splenium CC volume were negatively correlated with heroin duration and impulsivity traits. Further analyses demonstrated that impairment of VMHC of bilateral DLPFC partially mediated the association between genu CC volumes decreased and increased impulsivity in HDI. Our results reveal a substantial impairment of interhemispheric coordination in the HDI. Further, interhemispheric connectivity correlated with the duration of heroin abuse and higher impulsivity behavior in HDI. Our findings provide insight into a heroin addicts' related pathophysiology and reinforce an integrative view of the interhemispheric cerebral functional and structural organization.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Dependência de Heroína/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Adulto , Encéfalo/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/fisiopatologia , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/efeitos dos fármacos , Corpo Caloso/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
3.
Eur Radiol ; 27(3): 1161-1168, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27329520

RESUMO

OBJECTIVES: To characterize interhemispheric functional and anatomical connectivity and their relationships with impulsive behaviour in codeine-containing cough syrup (CCS)-dependent male adolescents and young adults. METHODS: We compared volumes of corpus callosum (CC) and its five subregion and voxel-mirrored homotopic functional connectivity (VMHC) in 33 CCS-dependent male adolescents and young adults and 38 healthy controls, group-matched for age, education and smoking status. Barratt impulsiveness scale (BIS.11) was used to assess participant impulsive behaviour. Abnormal CC subregions and VMHC revealed by group comparison were extracted and correlated with impulsive behaviour and duration of CCS use. RESULTS: We found selective increased mid-posterior CC volume in CCS-dependent male adolescents and young adults and detected decreased homotopic interhemispheric functional connectivity of medial orbitofrontal cortex (OFC). Moreover, impairment of VMHC was associated with the impulsive behaviour and correlated with the duration of CCS abuse in CCS-dependent male adolescents and young adults. CONCLUSIONS: These findings reveal CC abnormalities and disruption of interhemispheric homotopic connectivity in CCS-dependent male adolescents and young adults, which provide a novel insight into the impact of interhemispheric disconnectivity on impulsive behaviour in substance addiction pathophysiology. KEY POINTS: • CCS-dependent individuals (patients) had selective increased volumes of mid-posterior corpus callosum • Patients had attenuated interhemispheric homotopic FC (VMHC) of bilateral orbitofrontal cortex • Impairment of VMHC correlated with impulsive behaviour in patients • Impairment of VMHC correlated with the CCS duration in patients.


Assuntos
Codeína , Corpo Caloso/diagnóstico por imagem , Transtornos Relacionados ao Uso de Opioides/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Adolescente , Adulto , Antitussígenos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/fisiopatologia , Mapeamento Encefálico , Estudos de Casos e Controles , China , Corpo Caloso/patologia , Corpo Caloso/fisiopatologia , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Transtornos Relacionados ao Uso de Opioides/fisiopatologia , Tamanho do Órgão , Córtex Pré-Frontal/patologia , Córtex Pré-Frontal/fisiopatologia , Adulto Jovem
4.
J Magn Reson Imaging ; 45(1): 177-186, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27341655

RESUMO

PURPOSE: To identify codeine-containing cough syrups (CCS)-related modulations of intrinsic connectivity network (ICN) and to investigate whether these changes of ICN can be related to duration of CCS use and to impulsivity behavior in CCS-dependent individuals. MATERIALS AND METHODS: Resting-state functional magnetic resonance imaging (fMRI) data in 41 CCS-dependent individuals and 34 healthy controls (HC) were scanned at 1.5T and analyzed using independent component analysis (ICA), in combination with a "dual-regression" technique to identify the group differences of three important resting-state networks, the default mode network (DMN), the executive control network (ECN), and the salience network (SN) between the CCS-dependent individuals and HC. RESULTS: Compared with the HC, CCS-dependent individuals had aberrant intrinsic connectivity within the DMN, ECN, and SN (P < 0.05, AlphaSim corrected). Furthermore, a longer duration of CCS use was associated with greater abnormalities in the intrinsic network functional connectivity (FC, P < 0.05, Bonferroni correction). Intrinsic network FC also correlated with higher impulsivity in CCS-dependent individuals (P < 0.05, AlphaSim corrected). CONCLUSION: Our findings revealed aberrant DMN, ECN, and SN connectivity patterns in CCS-dependent patients, which may provide new insight into how neuronal communication and information integration are disrupted among DMN, ECN, and SN key structures due to long duration of CCS use. LEVEL OF EVIDENCE: 1 J. Magn. Reson. Imaging 2017;45:177-186.


Assuntos
Antitussígenos/efeitos adversos , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Codeína/efeitos adversos , Conectoma/métodos , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/fisiopatologia , Humanos , Masculino , Rede Nervosa/efeitos dos fármacos , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiopatologia , Reprodutibilidade dos Testes , Descanso , Sensibilidade e Especificidade , Adulto Jovem
5.
Brain Imaging Behav ; 11(5): 1470-1478, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27738991

RESUMO

Adolescence is a unique period in neurodevelopment. Dextromethorphan (DXM)-containing cough syrups are new addictive drugs used by adolescents and young adults. The effects of chronic DXM abuse on neurodevelopment in adolescents and young adults are still unknown. The aim of this study was to investigate the differences in cortical thickness and subcortical gray matter volumes between DXM-dependent adolescents and young adults and healthy controls, and to explore relationships between alternations in cortical thickness/subcortical volume and DXM duration, initial age of DXM use, as well as impulsive behavior in DXM-dependent adolescents and young adults. Thirty-eight DXM-dependent adolescents and young adults and 18 healthy controls underwent magnetic resonance imaging scanning, and cortical thickness across the continuous cortical surface was compared between the groups. Subcortical volumes were compared on a structure-by-structure basis. DXM-dependent adolescents and young adults exhibited significantly increased cortical thickness in the bilateral precuneus (PreC), left dorsal lateral prefrontal cortex (DLPFC. L), left inferior parietal lobe (IPL. L), right precentral gyrus (PreCG. R), right lateral occipital cortex (LOC. R), right inferior temporal cortex (ITC. R), right lateral orbitofrontal cortex (lOFC. R) and right transverse temporal gyrus (TTG. R) (all p < 0.05, multiple comparison corrected) and increased subcortical volumes of the right thalamus and right pallidum. There was a significant correlation between initial age of DXM use and cortical thickness of the DLPFC. L and PreCG. R. A significant correlation was also found between cortical thickness of the DLPFC. L and impulsive behavior in patients. This was the first study to explore relationships between cortical thickness/subcortical volume and impulsive behavior in adolescents dependent on DXM. These structural changes might explain the neurobiological mechanism of impulsive behavior in adolescent DXM users.


Assuntos
Antitussígenos/efeitos adversos , Encéfalo/efeitos dos fármacos , Dextrometorfano/efeitos adversos , Substância Cinzenta/efeitos dos fármacos , Transtornos Relacionados ao Uso de Substâncias/diagnóstico por imagem , Antitussígenos/administração & dosagem , Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Estudos de Casos e Controles , Estudos Transversais , Dextrometorfano/administração & dosagem , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/crescimento & desenvolvimento , Substância Cinzenta/patologia , Humanos , Comportamento Impulsivo , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão , Estudos Prospectivos , Transtornos Relacionados ao Uso de Substâncias/patologia , Transtornos Relacionados ao Uso de Substâncias/psicologia , Adulto Jovem
6.
Oncol Rep ; 36(6): 3700-3706, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27748902

RESUMO

The present study aimed to investigate the proteomic difference between melanosis coli (MC) alone and melanosis coli with colon cancer (MCCC). Protein expression in patients with different diseases was analyzed using two-dimensional gel electrophoresis and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/TOF-MS). A total of 14 protein differences with a confidence level of >95% were found. There were six differences between MC and normal tissues, in which two proteins exhibited upregulated expression levels and four proteins exhibited downregulated expression levels in MC. Furthermore, one protein was expressed only in MC (P<0.05). In addition, there were differences in the expression of eight proteins between MC and MCCC tissues, in which one protein had an upregulated expression in MC tissues and seven proteins had an upregulated expression in MCCC tissues. Furthermore, two proteins were only expressed in MCCC tissues (P<0.05). Eight proteins were identified using mass spectrometry and database search. In conclusion, comparative proteomics accurately displayed the expression differences in eight proteins between MC, MCCC and normal colon tissues.


Assuntos
Colo/metabolismo , Neoplasias do Colo/metabolismo , Melanose/metabolismo , Proteoma/metabolismo , Biomarcadores Tumorais/metabolismo , Estudos de Casos e Controles , Colo/patologia , Eletroforese em Gel Bidimensional , Humanos , Proteômica
7.
Eur Radiol ; 26(9): 2964-73, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26662031

RESUMO

OBJECTIVE: To investigate alterations of resting brain function in codeine-containing cough syrups (CCS) dependent individuals before and after ultra-rapid opioid detoxification under general anaesthesia (UROD) combined with naltrexone treatment (NMT). METHODS: Fourteen CCS-dependent individuals were scanned using resting-state fMRI. After UROD and 2 weeks of NMT, CCS-dependent individuals were rescanned. Fourteen matched controls were studied at baseline and compared. The amplitude of low frequency fluctuations (ALFF) and seed-based functional connectivity (FC) were used to characterize resting-state cerebral function. RESULTS: After UROD and 2 weeks of NMT, CCS-dependent individuals had increased ALFF in the bilateral parahippocampal gyrus and right medial orbitofrontal cortex (mOFC), decreased ALFF in the left post-central gyrus (PoCG), left middle occipital cortex (MOC) and left dorsal lateral prefrontal cortex (DLPFC), and reduced FC between right mOFC and right DLPFC, and between left DLPFC and left inferior parietal lobe relative to pretreatment. Decreased ALFFs in the left PoCG and left MOC were associated with decreased withdrawal syndrome severity in CCS-dependent individuals. CONCLUSIONS: We offer the first report describing how regional and integral synchronous neural activity occurs after UROD and short-term NMT, accompanied by decreased withdrawal syndrome severity. These findings contribute to the understanding of complex systems involved in UROD-NMT effects. KEY POINTS: • CCS-dependent individuals had reduced ALFF and increased FC at baseline. • UROD treatment can change the regional and integral brain function of CCS-dependent individuals. • Attenuated ALFFs are correlated with the withdrawal syndrome after treatment.


Assuntos
Anestesia Geral , Encéfalo/efeitos dos fármacos , Codeína/intoxicação , Naltrexona/uso terapêutico , Tratamento de Substituição de Opiáceos/métodos , Transtornos Relacionados ao Uso de Opioides/reabilitação , Adulto , Antitussígenos/intoxicação , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Antagonistas de Entorpecentes/uso terapêutico , Estudos Prospectivos , Síndrome de Abstinência a Substâncias/diagnóstico por imagem , Síndrome de Abstinência a Substâncias/fisiopatologia , Resultado do Tratamento , Adulto Jovem
8.
PLoS One ; 9(2): e87114, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24516545

RESUMO

OBJECTIVE: To prospectively investigate and detect early cerebral regional homogeneity (ReHo) changes in neurologically asymptomatic patients with end stage renal disease (ESRD) using in vivo resting-state functional MR imaging (Rs-fMRI). METHODS: We enrolled 20 patients (15 men, 5 women; meanage, 37.1 years; range, 19-49 years) with ESRD and 20 healthy controls (15 men, 5 women; mean age, 38.3 years; range, 28-49 years). The mean duration of hemodialysis for the patient group was 10.7±6.4 monthes. There was no significant sex or age difference between the ESRD and control groups. Rs-fMRI was performed using a gradient-echo echo-planar imaging sequence. ReHo was calculated using software (DPARSF). Voxel-based analysis of the ReHo maps between ESRD and control groups was performed with a two-samples t test. Statistical maps were set at P value less than 0.05 and were corrected for multiple comparisons. The Mini-Mental State Examination (MMSE) was administered to all participants at imaging. RESULTS: ReHo values were increased in the bilateral superior temporal gyrus and left medial frontal gyrus in the ERSD group compared with controls, but a significantly decreased ReHo value was found in the right middle temporal gyrus. There was no significant correlation between ReHo values and the duration of hemodialysis in the ESRD group. Both the patients and control subjects had normal MMSE scores (≥28). CONCLUSIONS: Our finding revealed that abnormal brain activity was distributed mainly in the memory and cognition related cotices in patients with ESRD. The abnormal spontaneous neuronal activity in those areas provide information on the neural mechanisms underlying cognitive impairment in patients with ESRD, and demonstrate that Rs-fMRI with ReHo analysis is a useful non-invasive imaging tool for the detection of early cerebral ReHo changes in hemodialysis patients with ESRD.


Assuntos
Encéfalo/patologia , Encéfalo/fisiopatologia , Falência Renal Crônica/fisiopatologia , Imageamento por Ressonância Magnética , Diálise Renal , Descanso , Adulto , Mapeamento Encefálico , Estudos de Casos e Controles , Demografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Drug Alcohol Depend ; 134: 314-321, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24286968

RESUMO

OBJECTIVE: To characterize the association between clinical symptoms and anatomical and functional cerebral deficits in codeine-containing cough syrups (CCS) users using voxel-based morphometry and resting state functional connectivity analysis. METHODS: Participants were 30 CCS users and 30 matched controls. Both groups were scanned using a volumetric three-dimensional fast field echo sequence and a gradient-echo echo-planar imaging sequence. Impulsivity traits of both groups were evaluated with the Barratt Impulsiveness Scale 11 (BIS 11). Voxel-based morphometry was used to characterize gray matter (GM) deficits in CCS users. The clinical significance of regional volume reduction was investigated by evaluating its association with impulsivity in CCS users and with alterations in resting state functional connectivity when brain regions with GM volume reduction were used as seed areas. RESULTS: Significantly decreased GM volume was observed in CCS users in bilateral ventral medial prefrontal cortex (vmPFC) which was related to greater impulsivity in CCS users. Significantly decreased integration was found in CCS users between the vmPFC and the default mode network. Also, significantly enhanced functional connectivity was found between the vmPFC and the right insula, and the right dorsal lateral PFC. Negative correlation was observed between BIS total scores, scores for attentional impulsivity and vmPFC-inferior parietal lobe connectivity in CCS users. CONCLUSIONS: The findings revealed volume loss and aberrant functional organization in vmPFC among CCS users. In addition, the decreased vmPFC GM volume and attenuated functional connectivity of the vmPFC-inferior parietal lobe network were associated with clinical higher impulsivity trait in CCS users.


Assuntos
Codeína/efeitos adversos , Rede Nervosa/patologia , Medicamentos sem Prescrição/efeitos adversos , Córtex Pré-Frontal/patologia , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Rede Nervosa/efeitos dos fármacos , Rede Nervosa/fisiologia , Tamanho do Órgão , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiologia , Estudos Prospectivos , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Adulto Jovem
10.
Liver Int ; 33(3): 375-83, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23402608

RESUMO

BACKGROUND: Many studies have reported that cognitive deficits exist in cirrhotic patients without overt hepatic encephalopathy (OHE). However, the neurobiological mechanisms underlying these deficits are still not fully understood. AIM: To investigate regional activity abnormalities in patients with hepatitis B virus-related cirrhosis (HBV-RC) without OHE using resting-state functional MRI (Rs-fMRI), and to examine the relationship between regional activity abnormalities and impaired cognition. METHODS: A newly reported regional homogeneity (ReHo) approach was used to compare the local synchronization of Rs-fMRI signals in 32 patients with HBV-RC without OHE and 32 well-matched healthy controls. Cognition was measured in all patients using psychometric hepatic encephalopathy score (PHES) tests, and the relationship between ReHo variation and PHES was analysed. RESULTS: Relative to healthy controls, the cirrhosis group showed high ReHo in the prefrontal cortex, and widespread low ReHo in visual association areas (left lingual gyrus, middle temporal gyrus and right middle occipital gyrus), motor association areas (bilateral precentral gyrus and paracentral lobule) and the bilateral precuneus. Correlation analysis of the mean ReHo values in different brain areas and PHES in cirrhotic patients revealed a significantly positive correlation in the left lingual gyrus (r = 0.352; P = 0.048), right middle occipital gyrus (r = 0.453; P = 0.009) and bilateral precentral gyrus (left: r = 0.436, P = 0.013; right: r = 0.582, P < 0.001), paracentral lobule (r = 0.485; P = 0.005) and precuneus (r = 0.468; P = 0.007). CONCLUSIONS: Our results provide information on the pathophysiological mechanisms underlying cognitive alterations in cirrhotic patients and demonstrate the feasibility of using Rs-fMRI with ReHo analysis as a noninvasive modality with which to detect the progression of cognitive changes in cirrhotic patients.


Assuntos
Encéfalo/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Hepatite B/complicações , Cirrose Hepática/etiologia , Cirrose Hepática/fisiopatologia , Adulto , China , Transtornos Cognitivos/etiologia , Feminino , Humanos , Cirrose Hepática/complicações , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Prospectivos
11.
Neurosci Lett ; 538: 43-8, 2013 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-23352851

RESUMO

PURPOSE: Chronic exposure to heroin induced cerebral structural abnormalities may underlie heroin-related behaviors. The aim of this study was to: (1) identify cerebral structural abnormalities in heroin-dependent individuals (HDIs) by an automated and unbiased morphometric technique. (2) Define the correlation between these cerebral structural abnormalities and the impulsivity characteristic in HDIs. METHODS: 24 HDIs and 24 control subjects were completed with (1) high resolution structural magnetic resonance imaging scanning and analysis of gray matter volume using voxel-based morphometry implemented in Statistical Parametric Mapping and (2) a Chinese translation Barratt Impulsiveness Scale-11 questionnaire survey. Differences in regional gray matter volume were tested using an analysis of covariance model, co-varying for global gray matter and age. Statistical maps were set at p<0.05, corrected for multiple comparisons. The abnormal brain regions were correlated with the duration of heroin use and impulsivity scores. RESULTS: After adjusting for effects of age and total gray matter volume, cortical gray matter volume in the bilateral medial prefrontal cortex, bilateral dorsal lateral prefrontal cortex, and right fusiform cortex were significantly reduced in HDIs. Moreover, the gray matter volume in prefrontal cortex that showed group differences was negatively correlated with the duration of heroin use and negatively correlated with the impulsivity characteristic in HDIs. CONCLUSION: These findings reveal the prefrontal cortex was impaired in HDIs, meanwhile, indicate the changes in gray matter volume are relating to the duration of heroin use and the impulsivity characteristic of the HDIs.


Assuntos
Dependência de Heroína/patologia , Córtex Pré-Frontal/patologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Fatores de Tempo
12.
Radiology ; 261(2): 551-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21875854

RESUMO

PURPOSE: To identify heroin-related modulations of neural activity in the resting state in heroin-dependent individuals (HDIs) by using resting-state functional magnetic resonance (MR) imaging and a regional homogeneity method and to investigate whether these changes of neural activity can be related to duration of heroin use and to decision-making deficits in HDIs. MATERIALS AND METHODS: This prospective study was approved by the appropriate ethics committee, and written informed consent was obtained from each participant. Thirty-one HDIs receiving methadone-maintained treatment and 24 control subjects participated. Resting-state functional MR imaging was performed by using a gradient-echo echo-planar imaging sequence. Regional homogeneity was calculated by using software. Voxel-based analysis of the regional homogeneity maps between control and HDI groups was performed with two-sample t tests by using software. Statistical maps were set at P less than .05 and were corrected for multiple comparisons. The Iowa gambling task (IGT) was used to assess participant decision making during uncertainty. Abnormal clusters revealed by group comparison were extracted and correlated with behavioral performance at the IGT and with duration of heroin use. RESULTS: Regional homogeneity was diminished in the bilateral medial orbitofrontal cortex (OFC), bilateral dorsal medial thalamus, bilateral cuneus, and lingual gyrus in HDIs compared with control subjects. There were negative correlations between mean regional homogeneity in the medial OFC, bilateral cuneus, and lingual gyrus and duration of heroin use. There was a positive correlation between mean regional homogeneity in the medial OFC and performance level at the IGT. CONCLUSION: The present study reveals resting-state abnormalities in HDIs that may lead to further improvement of the understanding of the neural substrates of cognitive impairment in HDIs.


Assuntos
Encéfalo/patologia , Dependência de Heroína/patologia , Imageamento por Ressonância Magnética/métodos , Vias Neurais/patologia , Adulto , Mapeamento Encefálico/métodos , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Tomada de Decisões , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estatísticas não Paramétricas , Análise e Desempenho de Tarefas
13.
Nan Fang Yi Ke Da Xue Xue Bao ; 28(12): 2235-8, 2008 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-19114368

RESUMO

OBJECTIVE: To analyze the computed tomography (CT) and magnetic resonance imaging (MRI) findings of small hepatocellular carcinoma to improve the accuracy in the diagnosis. METHODS: This retrospective analysis involved 41 patients with small hepatocellular carcinoma cases confirmed by pathological examination of the biopsy samples or follow-up. These patients were assessed for CT and MRI findings including lesion size, density or signal intensity, enhancement patterns, and presence of tumor capsules. RESULTS: On unenhanced CT images, small hepatocellular carcinomas were displayed mainly as low-density masses, and the majority of tumors presented with low signal intensity on T1-weighted unenhanced MR images with increased signal intensity on T2-weighted images in comparison with the surrounding liver parenchyma. Most of tumors showed intense enhancement during the arterial phase (CT in 15 cases and MRI in 13 cases), but some appeared isointense to the liver parenchyma (CT in 4 cases and MRI in 4 cases). In portal and delayed phases, the tumors typically had lower signal intensity than that of the surrounding liver tissues (CT in 25 cases and MRI in 12 cases) with enhancement of the tumor capsules (13 cases). CONCLUSION: Dynamic enhanced scanning can be more informative of the pathology and blood supply of small hepatocellular carcinoma. Early and late arterial phase imaging may help in detecting the small lesions and in making differential diagnosis.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Adulto , Idoso , Carcinoma Hepatocelular/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Aumento da Imagem , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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