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1.
Angew Chem Int Ed Engl ; 60(39): 21536-21542, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34260129

RESUMEN

The Buchwald-Hartwig C-N coupling reaction has found widespread applications in organic synthesis. Over the past two decades or so, many improved catalysts have been introduced, allowing various amines and aryl electrophiles to be readily used nowadays. However, there lacks a protocol that could be used to couple a wide range of chiral amines and aryl halides, without erosion of the enantiomeric excess (ee). Reported in this article is a method based on molecular Ni catalysis driven by light, which enables stereoretentive C-N coupling of optically active amines, amino alcohols, and amino acid esters with aryl bromides, with no need for any external photosensitizer. The method is effective for a wide variety of coupling partners, including those bearing functional groups sensitive to bases and nucleophiles, thus providing a viable alternative to accessing synthetically important chiral N-aryl amines, amino alcohols, and amino acids esters. Its viability is demonstrated by 92 examples with up to 99 % ee.

2.
Metab Brain Dis ; 33(6): 1887-1897, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30187180

RESUMEN

To assess whether EGb761 could protect elderly diabetic mice with cognitive disorders and explore the role of beclin-1-mediated autophagy in these protective effects. Two-month-old male db/db-/- mice and wild-type C57/BL6 mice were randomly divided into six groups: db/db-/- control, db/db-/- 50 mg, db/db-/- 100 mg, wild-type (WT) control, WT 50 mg, and WT 100 mg. EGb761 (50 mg/kg or 100 mg/kg of bodyweight) was given by gavage once a day for 1 month from the age of 6 months. Y-maze and social choice tests were performed at 8th months. The blood pressure was measured. The imaging changes in the brain were measured using magnetic resonance imaging (MRI). The expression and distribution of beclin-1, LC3, and NF-κB were detected using immunohistochemistry staining and western blotting. Ultrastructure alterations in the hippocampus were observed using transmission electron microscopy. Compared with WT mice, the learning ability, memory and overall cognitive function of db/db-/- mice decreased (P < 0.05), and EGb761 could significantly improve the learning and memory function of db/db-/- mice (P < 0.05). EGb761 significantly improved systolic blood pressure in db/db-/- mice (P < 0.01). In addition, fMRI-bold showed a decline in the hippocampus of mice in the db/db-/- group compared with WT. EGb761 could improve these above changes. Immunohistochemistry staining and western blotting confirmed that EGb761 significantly increased beclin-1 and reduced LC3-II/I levels in the brains of db/db-/- mice (P < 0.05). NF-κB levels were obviously higher in the db/db-/- group than that in the WT group, and EGb761 significantly reduced NF-κB levels in db/db-/- mice (P < 0.05). There was a trend of increased autophagosomes in db/db-/- mice, but EGb761 did not change obviously the number of autophagosomes. Compared with normal aged WT mice, aging db/db-/- mice had more common complications of cerebral small vessel disease and cognitive dysfunction. EGb761 could significantly improve the cognitive function of aging db/db-/- mice via a mechanism that may involve the regulation of beclin-1, LC3, and NF-κB.


Asunto(s)
Envejecimiento/metabolismo , Beclina-1/metabolismo , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/metabolismo , FN-kappa B/metabolismo , Extractos Vegetales/uso terapéutico , Envejecimiento/efectos de los fármacos , Envejecimiento/genética , Animales , Beclina-1/agonistas , Disfunción Cognitiva/genética , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Relación Dosis-Respuesta a Droga , Ginkgo biloba , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Aprendizaje por Laberinto/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , FN-kappa B/antagonistas & inhibidores , Extractos Vegetales/farmacología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología
3.
J Neurol Neurosurg Psychiatry ; 85(1): 99-105, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23761913

RESUMEN

OBJECTIVE: Peripheral nerve injury can induce immediate and long-standing remodelling of the brain cortex, which may affect outcomes of nerve repair. This study examined changes of corresponding cortical representations in patients with brachial plexus injuries. METHODS: Resting-state fMRI was acquired for 13 adult patients with total brachial plexus root avulsion, three of whom underwent second scans 7 or 8 months later. The time of examination ranged from 1 to 16 months after injuries. Nine healthy adults were enrolled as control. Seed-based functional connectivity was performed for all subjects. RESULTS: For nine patients whose first fMRI was performed from 1 to 4 months after brachial plexus injuries, images showed that their cortical maps of sensorimotor areas corresponding to the hand and arm in the hemisphere contralateral to the injured side had much weaker correlation with the supplementary motor area (SMA) than those ipsilateral to the injured side. Symmetrical maps of bilateral cortical sensorimotor areas corresponding to the hand and arm were observed in other four cases with fMRI tested from 7 to 16 months after injuries. For three of the nine patients with asymmetrical cortical representations, second scans indicated symmetric results or even stronger correlation with SMA in the cerebral cortex contralateral to the injured side. CONCLUSIONS: Total brachial plexus root avulsion causes cortical representations of the brachial plexus to undergo a change from an inactive to an active state. This implies that peripheral deafferentation after brachial plexus injuries will induce corresponding cortical representations to be occupied by adjacent non-deafferented cortical territories.


Asunto(s)
Neuropatías del Plexo Braquial/patología , Plexo Braquial/lesiones , Corteza Motora/patología , Corteza Somatosensorial/patología , Accidentes de Tránsito , Adulto , Plexo Braquial/cirugía , Neuropatías del Plexo Braquial/cirugía , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Motocicletas , Transferencia de Nervios/métodos , Procedimientos Neuroquirúrgicos/métodos , Oxígeno/sangre , Descanso , Trastornos de la Sensación/etiología , Nervios Espinales/patología , Resultado del Tratamiento , Adulto Joven
4.
Acta Neurochir (Wien) ; 156(12): 2295-302, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25246146

RESUMEN

BACKGROUND: Resting-state functional magnetic resonance imaging (R-fMRI) is a promising tool in clinical application, especially in presurgical mapping for neurosurgery. This study aimed to investigate the sensitivity and specificity of R-fMRI in the localization of hand motor area in patients with brain tumors validated by direct cortical stimulation (DCS). We also compared this technique to task-based blood oxygenation level-dependent (BOLD) fMRI (T-fMRI). METHODS: R-fMRI and T-fMRI were acquired from 17 patients with brain tumors. The cortex sites of the hand motor area were recorded by DCS. Site-by-site comparisons between R-fMRI/T-fMRI and DCS were performed to calculate R-fMRI and T-fMRI sensitivity and specificity using DCS as a "gold standard". R-fMRI and T-fMRI performances were compared statistically RESULTS: A total of 609 cortex sites were tested with DCS and compared with R-fMRI findings in 17 patients. For hand motor area localization, R-fMRI sensitivity and specificity were 90.91 and 89.41 %, respectively. Given that two subjects could not comply with T-fMRI, 520 DCS sites were compared with T-fMRI findings in 15 patients. The sensitivity and specificity of T-fMRI were 78.57 and 84.76 %, respectively. In the 15 patients who successfully underwent both R-fMRI and T-fMRI, there was no statistical difference in sensitivity or specificity between the two methods (p = 0.3198 and p = 0.1431, respectively) CONCLUSIONS: R-fMRI sensitivity and specificity are high for localizing hand motor area and even equivalent or slightly higher compared with T-fMRI. Given its convenience for patients, R-fMRI is a promising substitute for T-fMRI for presurgical mapping.


Asunto(s)
Mapeo Encefálico/métodos , Mano/inervación , Imagen por Resonancia Magnética/métodos , Corteza Motora/fisiopatología , Adulto , Neoplasias Encefálicas/diagnóstico , Estimulación Encefálica Profunda , Femenino , Glioma/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
5.
Acta Neurochir (Wien) ; 156(10): 1837-45, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25002281

RESUMEN

BACKGROUND: The ability of preoperative MRI-sequences to predict the consistency of intracranial meningiomas has not yet been clearly defined. We aim to demonstrate that diffusion tensor imaging (DTI) improves the prediction of intracranial meningiomas consistency. METHODS: We prospectively studied 110 meningioma patients operated on in a single center from March 1st to the 25th of May 2012. Demographic data, location and size of the tumor, peritumoral edema, T1WI, T2WI, proton density weighted (PDWI), fluid-attenuated inversion recover (FLAIR) sequences, and arterial spin labeling (ASL) perfusion were studied and compared with the gray matter signal to predict meningioma consistency. Diffusion tensor imaging (DTI) with fractional anisotropy (FA) and mean diffusivity (MD) maps were included in the preoperative MRI. Meningioma consistency was evaluated by the operating surgeon who was unaware of the neuroradiological findings. RESULTS: In univariate analysis, meningioma size (diameter > 2 cm) and supratentorial or sphenoidal wing location were more frequently associated with hard-consistency meningiomas (p < 0.05). In addition, isointense signal on MD maps (p = 0.009), hyperintense signal on FA maps, and FA value > 0.3 (p = 0.00001) were associated with hard-consistency tumors. Age and sex, T1WI, T2WI, PDWI, FLAIR, or ASL perfusion sequences and peritumoral edema were not significantly associated with meningioma consistency. In logistic regression analysis, the most accurate model (AUC: 0.9459) for predicting a hard-consistency meningioma shows that an isointense signal in MD-maps, a hyperintense signal in FA-maps, and an FA value of more than 0.3 have a significant predictive value. CONCLUSIONS: FA value and MD and FA maps are useful for prediction of meningioma consistency and, therefore, may be considered in the preoperative routine MRI examination of all patients with intracranial meningiomas.


Asunto(s)
Imagen de Difusión Tensora/métodos , Neoplasias Meníngeas/diagnóstico , Meningioma/diagnóstico , Adulto , Anciano , Femenino , Humanos , Masculino , Neoplasias Meníngeas/clasificación , Neoplasias Meníngeas/patología , Meningioma/clasificación , Meningioma/patología , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico
6.
Neuroradiology ; 55(1): 41-8, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22922867

RESUMEN

INTRODUCTION: Sensory neuronopathy (SNN) is a distinctive subtype of peripheral neuropathies, specifically targeting dorsal root ganglion (DRG). We utilized MRI to demonstrate the imaging characteristics of DRG, spinal cord (SC), and brachial plexus at C7 level in SNN. METHODS: We attempted multiple-echo data image combination (MEDIC) and turbo inversion recovery magnitude (TIRM) methods in nine patients with sensory neuronopathy and compared with those in 16 disease controls and 20 healthy volunteers. All participants underwent MRI for the measurement of DRG, posterior column (PC), lateral column, and spinal cord area (SCA) at C7 level. DRG diameters were obtained through its largest cross section, standardized by dividing sagittal diameter of mid-C7 vertebral canal. We also made comparisons of standardized anteroposterior diameter (APD) and left-right diameters of SC and PC in these groups. Signal intensity and diameter of C7 spinal nerve were assessed on TIRM. RESULTS: Compared to control groups, signal intensities of DRG and PC were higher in SNN patients when using MEDIC, but the standardized diameters were shorter in either DRG or PC. Abnormal PC signal intensities were identified in eight out of nine SNN patients (89 %) with MEDIC and five out of nine (56 %) with T2-weighted images. SCA, assessed with MEDIC, was smaller in SNN patients than in the other groups, with significant reduction of its standardized APD. C7 nerve root diameters, assessed with TIRM, were decreased in SNN patients. CONCLUSION: MEDIC and TIRM sequences demonstrate increased signal intensities and decreased area of DRG and PC, and decreased diameter of nerve roots in patients with SNN, which can play a significant role in early diagnosis.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Enfermedades del Sistema Nervioso Periférico/patología , Trastornos de la Sensación/patología , Adulto , Anciano , Plexo Braquial , Femenino , Ganglios Espinales , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Médula Espinal , Adulto Joven
7.
Zhong Xi Yi Jie He Xue Bao ; 10(7): 766-76, 2012 Jul.
Artículo en Zh | MEDLINE | ID: mdl-22805083

RESUMEN

BACKGROUND: Alzheimer disease (AD) is a chronic neurodegenerative disease that is characterized by its gradual progression. At present, the cause and mechanism of AD are yet unclear, and there is no effective therapy for treating it. With development of global aging, the prevalence rate of AD is increasing. The life quality of elderly people is affected severely by AD that is ultimately life-threatening. Recently, study on treating AD with traditional Chinese medicine (TCM) has deepened. OBJECTIVE: To explore the therapeutic effects of a syndrome differentiation-based TCM regime in treating patients with mild to moderate AD for improving cognition, and to evaluate the changes in brain function of AD patients observed by resting-state functional magnetic resonance imaging (fMRI) technique. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: Adopting the internationally recognized criteria developed by National Institute of Neurological and Communicative Diseases and Stroke/Alzheimer's Disease and Related Disorders Association, the clinical trial was conducted on 131 patients with mild to moderate AD from 5 communities and 7 social welfare institutions. Participants were accepted after informed consent was received, and laboratory tests and a head imaging study were conducted. The patients were randomly divided into Chinese medicine group (CMG) (66 cases) or Western medicine group (WMG) (65 cases). Patients in the CMG were treated monthly with Chinese medicine according to syndrome differentiation. Patients in the WMG were treated with donepezil at a dose of 5 mg once daily. The therapeutic course lasted 48 weeks. MAIN OUTCOME MEASURES: The scores of Mini-Mental State Examination (MMSE), Fuld Object-Memory Evaluation (FOM), Block Design (BD) and Digit Span (DS) were used to evaluate the cognitive function; resting-state fMRI was used for observing brain function. The questionnaires and fMRI were performed before and after treatments. RESULTS: The cognitive functions of the patients in the CMG and WMG were improved after treatment. MMSE score was improved significantly in both groups (P<0.05 or P<0.001). After 48 weeks of treatment, 70.91% patients in the CMG had an improved MMSE score and 20% got worse, however, 55.77% patients in the WMG were improved in MMSE score and 34.62% got worse. Scores of FOM denominator and BD increased significantly in both groups; scores of FOM numerator and DS were also increased in the CMG (P<0.05 or P<0.01). The results of fMRI suggested that both Chinese medicine and donepezil treatment improved the connectivity between posterior cingulated gyrus and specific areas in the brain. The influence range of Chinese medicine primarily impacted on the left parietal lobe, being less than the influence range of donepezil, which primarily affected both sides of frontal lobes. CONCLUSION: TCM treatment based on syndrome differentiation is effective in improving cognitive function of patients with mild to moderate AD and increasing the brain function by increasing connectivity between posterior cingulated gyrus and specific areas in the brain.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Cognición/efectos de los fármacos , Donepezilo , Humanos , Indanos/uso terapéutico , Nootrópicos/uso terapéutico , Piperidinas/uso terapéutico
8.
Zhonghua Yi Xue Za Zhi ; 91(23): 1600-4, 2011 Jun 21.
Artículo en Zh | MEDLINE | ID: mdl-21914391

RESUMEN

OBJECTIVE: To evaluate the severity of punctate white matter lesions (PWML) in neonatal brain injury with susceptibility weighted imaging (SWI) and explore the value and limitation of SWI versus the conventional magnetic resonance imaging (MRI). METHODS: A total of 34 neonates presenting with PWML at initial MRI were recruited for this prospective study. PWML were defined as punctuate lesions with T(1) hyperintensity and T(2) isointensity or hypointensity in white matter. There were 21 males and 13 females with a median age of 9.24 days (range: 2 - 17 days). All MRI examinations were performed at 1.5 Tesla unit including conventional MRI (T(1), T(2) & Flair sequences), DWI and SWI. PWML were classified into two groups: (1) T(1) hyperintensity & T(2) isointensity; (2) T(1) hyperintensity & T(2) hypointensity. The manifestations of PWML on SWI were analyzed. RESULTS: Among all cases, only 5 cases (14.7%) demonstrated an evidence of hemorrhage on SWI. There were 7 cases in Group 1. Only 1 case showed punctate hypointensity in the areas of PWML on SWI while there was no hemorrhage on SWI in other 6 cases. Twenty-seven cases were in Group 2. Only 4 cases showed an evidence of hemorrhage on SWI while hemorrhage was absent on SWI in other 23 cases. CONCLUSION: Most areas of PWML in neonatal brain show no hemorrhage on SWI. And SWI can help to identify whether or not hemorrhage is present in PWML of neonates.


Asunto(s)
Encefalopatías/patología , Imagen de Difusión por Resonancia Magnética/métodos , Femenino , Humanos , Recién Nacido , Magnetismo , Masculino , Estudios Prospectivos
9.
Acta Neurochir (Wien) ; 152(11): 1847-57, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20652607

RESUMEN

OBJECTIVE: Resection of gliomas invading primary motor cortex and subcortical motor pathway is difficult in both surgical decision-making and functional outcome prediction. In this study, magnetic resonance (MR) diffusion tensor imaging (DTI) data were used to perform tractography to visualize pyramidal tract (PT) along its whole length in a stereoscopic virtual reality (VR) environment. The potential value of its clinical application was evaluated. METHODS: Both three-dimensional (3-D) magnetic resonance imaging (MRI) and DTI datasets were obtained from 45 eligible patients with suspected cerebral gliomas and then transferred to the VR system (Dextroscope; Volume Interactions Pte. Ltd., Singapore). The cortex and tumor were segmented and reconstructed via MRI, respectively, while the tractographic PTs were reconstructed via DTI. All those were presented in a stereoscopic 3-D display synchronously, for the purpose of patient-specific presurgical planning and surgical simulation in each case. The relationship between increasing amplitude of the number of effective fibers of PT (EPT) at affected sides and the patients' Karnofsky Performance Scale (KPS) at 6 months was addressed out. RESULTS: In VR presurgical planning for gliomas, surgery was aided by stereoscopic 3-D visualizing the relative position of the PTs and a tumor. There was no significant difference between pre- and postsurgical EPT in this population. A positive relationship was proved between EPT increasing amplitude and 6-month KPS. CONCLUSIONS: 3-D stereoscopic visualization of tractography in this VR environment enhances the operators to well understand the anatomic information of intra-axial tumor contours and adjacent PT, results in surgical trajectory optimization initially, and maximal safe tumor resection finally. In accordance to the EPT increasing amplitude, surgeon can predict the long-term motor functional outcome.


Asunto(s)
Neoplasias Encefálicas/patología , Glioma/patología , Neuronavegación/métodos , Cuidados Preoperatorios/métodos , Interfaz Usuario-Computador , Adolescente , Adulto , Anciano , Neoplasias Encefálicas/fisiopatología , Neoplasias Encefálicas/cirugía , Niño , Preescolar , Imagen de Difusión Tensora/métodos , Femenino , Glioma/fisiopatología , Glioma/cirugía , Humanos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Vías Nerviosas/fisiología , Vías Nerviosas/cirugía , Neuronavegación/instrumentación , Cuidados Preoperatorios/instrumentación , Adulto Joven
10.
Zhonghua Xin Xue Guan Bing Za Zhi ; 37(11): 1018-21, 2009 Nov.
Artículo en Zh | MEDLINE | ID: mdl-20137330

RESUMEN

OBJECTIVE: To explore the relationship between clinical ischemic events and carotid calcification detected by 64 slices CT angiography. METHODS: We retrospectively analyzed the carotid calcified plaques in 116 patients underwent the 64 slices CT angiography. The relationship between the carotid calcification and the clinical ischemic events was analyzed. RESULTS: A total of 377 plaques were detected and the incidence of carotid plaque calcification was 63.40%. Incidence of plaque calcification was significantly lower in patients with ages < 50 years than that in patients with ages 51 - 59 years, 60 - 69 years and higher than 70 years (P = 0.003, P = 0.002, P = 0.000, respectively). The incidence of plaque calcification in the common carotid artery was significantly lower than the carotid bifurcation (P = 0.000) and the internal carotid artery (P = 0.000). The incidences of calcification in the mild, moderate and severe degree of stenosis and occlusion were 46.54%, 33.33%, 26.67% and 0% respectively. The distribution of intraplaque calcium was similar between patients with ischemic event and non-ischemic event group. However, the incidence of calcification was significantly lower patients with ischemic event than that in patients without ischemic event (30.34% vs. 43.10%, P = 0.013). Calcified plaque was negatively associated with ischemic event (beta = -0.688, P = 0.006). CONCLUSION: 64 slices CT angiography can analyze the characterization of carotid plaque calcium.


Asunto(s)
Calcinosis/diagnóstico por imagen , Estenosis Carotídea/complicaciones , Isquemia Miocárdica/complicaciones , Tomografía Computarizada Espiral/métodos , Factores de Edad , Anciano , Calcinosis/complicaciones , Calcinosis/epidemiología , Estenosis Carotídea/diagnóstico por imagen , Humanos , Incidencia , Persona de Mediana Edad , Isquemia Miocárdica/diagnóstico por imagen , Estudios Retrospectivos
11.
Neural Regen Res ; 14(5): 868-875, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30688273

RESUMEN

Idiopathic rapid eye movement sleep behavior disorder (iRBD) is often a precursor to neurodegenerative disease. However, voxel-based morphological studies evaluating structural abnormalities in the brains of iRBD patients are relatively rare. This study aimed to explore cerebral structural alterations using magnetic resonance imaging and to determine their association with clinical parameters in iRBD patients. Brain structural T1-weighted MRI scans were acquired from 19 polysomnogram-confirmed iRBD patients (male:female 16:3; mean age 66.6 ± 7.0 years) and 20 age-matched healthy controls (male:female 5:15; mean age 63.7 ± 5.9 years). Gray matter volume (GMV) data were analyzed based on Statistical Parametric Mapping 8, using a voxel-based morphometry method and two-sample t-test and multiple regression analysis. Compared with controls, iRBD patients had increased GMV in the middle temporal gyrus and cerebellar posterior lobe, but decreased GMV in the Rolandic operculum, postcentral gyrus, insular lobe, cingulate gyrus, precuneus, rectus gyrus, and superior frontal gyrus. iRBD duration was positively correlated with GMV in the precuneus, cuneus, superior parietal gyrus, postcentral gyrus, posterior cingulate gyrus, hippocampus, lingual gyrus, middle occipital gyrus, middle temporal gyrus, and cerebellum posterior lobe. Furthermore, phasic chin electromyographic activity was positively correlated with GMV in the hippocampus, precuneus, fusiform gyrus, precentral gyrus, superior frontal gyrus, cuneus, inferior parietal lobule, angular gyrus, superior parietal gyrus, paracentral lobule, and cerebellar posterior lobe. There were no significant negative correlations of brain GMV with disease duration or electromyographic activity in iRBD patients. These findings expand the spectrum of known gray matter modifications in iRBD patients and provide evidence of a correlation between brain dysfunction and clinical manifestations in such patients. The protocol was approved by the Ethics Committee of Huashan Hospital (approval No. KY2013-336) on January 6, 2014. This trial was registered in the ISRCTN registry (ISRCTN18238599).

12.
J Neurosci Methods ; 167(2): 176-83, 2008 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-17889370

RESUMEN

In rat models to induce both focal cerebral ischemia and chronic cerebral hypoperfusion, it is highly desirable to verify the success of vessel occlusion and reopening with non-invasive method. The contrast-agent free 3D time-of-flight magnetic resonance angiography (TOF-MRA), diffusion-weighted imaging (DWI) and T2-weighted imaging by 3.0-T MR clinical scanner were applied when unilateral middle cerebral artery (MCA) was occluded and reopened, and after bilateral common carotid arteries were in ligation. The arterial angiograms of the rat brain and neck were achieved successfully in all chosen directions by the 3D TOF-MRA. It was shown that MCA in occlusion presented no signal in MRA, and the parenchyma of the ipsilateral MCA territory hypointensity signal in maps of apparent diffusion coefficient (ADC). After reperfusion, the signal intensity of ipsilateral MCA was resumed in MRA, and the decreased ADC was restored simultaneously. However, after 5h of reperfusion, it was found that the value of ADC deteriorated second time with high T2 value. In bilateral common carotid artery occlusion (BCCAO) rats, it can be confirmed by MRA that the effectively occluded BCCA presented the absent signal and the basilar artery became tortuous. As a result, MRA by clinical scanner was proved of a valuable method to validate transient middle cerebral artery occlusion (MCAO) and permanent BCCAO rat model.


Asunto(s)
Enfermedades de las Arterias Carótidas/diagnóstico , Infarto de la Arteria Cerebral Media/diagnóstico , Angiografía por Resonancia Magnética/métodos , Animales , Conducta Animal , Mapeo Encefálico , Modelos Animales de Enfermedad , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Ratas , Ratas Sprague-Dawley
13.
Neural Regen Res ; 13(6): 1061-1065, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29926834

RESUMEN

Research on brain function after brachial plexus injury focuses on local cortical functional reorganization, and few studies have focused on brain networks after brachial plexus injury. Changes in brain networks may help understanding of brain plasticity at the global level. We hypothesized that topology of the global cerebral resting-state functional network changes after unilateral brachial plexus injury. Thus, in this cross-sectional study, we recruited eight male patients with unilateral brachial plexus injury (right handedness, mean age of 27.9 ± 5.4 years old) and eight male healthy controls (right handedness, mean age of 28.6 ± 3.2). After acquiring and preprocessing resting-state magnetic resonance imaging data, the cerebrum was divided into 90 regions and Pearson's correlation coefficient calculated between regions. These correlation matrices were then converted into a binary matrix with affixed sparsity values of 0.1-0.46. Under sparsity conditions, both groups satisfied this small-world property. The clustering coefficient was markedly lower, while average shortest path remarkably higher in patients compared with healthy controls. These findings confirm that cerebral functional networks in patients still show small-world characteristics, which are highly effective in information transmission in the brain, as well as normal controls. Alternatively, varied small-worldness suggests that capacity of information transmission and integration in different brain regions in brachial plexus injury patients is damaged.

14.
Front Hum Neurosci ; 12: 426, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30459581

RESUMEN

Ocular hypertension (OHT), the common situation in adult patients in the outpatients, occurs ∼5% worldwide. However, there are still some practical problems in differentiation of OHT with early primary open-angle glaucoma (POAG) using current standard methods. Application of high resolution diffusion tensor imaging (DTI) enables us to the differentiate axonal architecture of visual pathway between POAG and OHT subjects. Among 32 POAG patients recruited (15 OHT and 14 control subjects), 62.5% of glaucoma were in early stage for the current study. All subjects underwent ophthalmological assessments with standard automated perimetry and optical coherence tomography (OCT). DTI was applied to measure fraction anisotropy (FA) and mean diffusivity (MD) of optic tract (OT), lateral geniculate body (LGN) and optic radiation (OR) using voxel-based analysis. Our data demonstrated that FA values of bilateral OR in POAG were significantly lower in the right or left than that of OHT patients (left OR: 0.51 ± 0.04 vs. 0.54 ± 0.03, p < 0.05; right OR: 0.51 ± 0.05 vs. 0.54 ± 0.03, p < 0.05). In right LGN, MD values were higher in POAG patients compared with OHT subjects (9.81 ± 1.45 vs. 8.23 ± 0.62, p < 0.05). However, no significant difference of all of the DTI parameters was observed between OHT and control subjects. DTI parameters in POAG patients were positively correlated with morphological and functional measurements (p < 0.05). Vertical cup to disc ratio (VCDR) was correlated with ipsilateral FA of OT (p < 0.05), ipsilateral MD of OT (p < 0.05), ipsilateral MD of LGN (p < 0.05), and contralateral MD of OT (p < 0.05). Mean deviation of visual field (MDVF) was correlated with ipsilateral FA of OT (p < 0.05), ipsilateral MD of OT (p < 0.05), and ipsilateral FA of LGN (p < 0.05). Our study demonstrated that DTI can differentiate POAG from OHT subjects in optic pathway, particularly in early POAG, and DTI parameters can quantify the progression of POAG.

15.
Chin J Integr Med ; 24(5): 328-335, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29752611

RESUMEN

OBJECTIVE: To compare the effects of electroacupuncture (EA) and mild-warm moxibustion (Mox) therapies for constipation-predominant irritable bowel syndrome (C-IBS) patients. METHODS: Sixty C-IBS patients were assigned to 2 groups by simple randomized method, i.e. EA group (30 cases) and Mox group (30 cases). Both EA and Mox treatments were performed on bilateral Tianshu (ST 25) and Shangjuxu (ST 37) for 30 min each time, 6 times per week, for 4 consecutive weeks. The gastrointestinal symptoms and psychological symptoms of the two groups were scored before and after treatment. The effects on the corresponding functional brain areas, namely the anterior cingulate cortex (ACC), insular cortex (IC) and prefrontal cortex (PFC) were observed by functional magnetic resonance imaging (fMRI) before and after treatment. RESULTS: Compared with the Mox group, greater improvements in abdominal distension, defecation frequency, diffificulty in defecation and stool features were observed in the EA group (all P<0.01), both Hamilton Anxiety Rating Scale and Hamilton Depression Rating Scale scores were signifificantly decreased in the EA group (all P<0.01). Finally, decreased activated voxel values were observed in the ACC, right IC and PFC brain regions of EA group with 150 mL colorectal distension stimulation (P<0.05 or P<0.01). CONCLUSIONS: Both EA and Mox could signifificantly improve some of the most intrusive symptoms of C-IBS patients, and EA was more effective than Mox. The therapeutic effect of these two therapies might through modulating of the brain-gut axis function. (Registration No. ChiCTRTRC-11001349).


Asunto(s)
Encéfalo/fisiopatología , Estreñimiento/fisiopatología , Estreñimiento/terapia , Electroacupuntura , Síndrome del Colon Irritable/fisiopatología , Síndrome del Colon Irritable/terapia , Moxibustión , Adulto , Electroacupuntura/efectos adversos , Humanos , Imagen por Resonancia Magnética , Moxibustión/efectos adversos , Dimensión del Dolor , Recto/fisiopatología , Umbral Sensorial/fisiología
16.
Org Lett ; 9(7): 1243-6, 2007 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-17328554

RESUMEN

[structure: see text]. The asymmetric hydrogenation of quinolines catalyzed by chiral dendritic catalysts derived from BINAP gave the corresponding products with high enantioselectivities (up to 93%), excellent catalytic activities (TOF up to 3450 h(-1)), and productivities (TON up to 43,000). In addition, the third-generation catalyst could be recovered by precipitation and filtration and reused at least six times with similar enantioselectivity.


Asunto(s)
Dendrímeros , Iridio/química , Naftalenos , Compuestos Organometálicos , Quinolinas/química , Catálisis , Dendrímeros/síntesis química , Dendrímeros/química , Hidrogenación , Estructura Molecular , Naftalenos/síntesis química , Naftalenos/química , Compuestos Organometálicos/síntesis química , Compuestos Organometálicos/química , Estereoisomerismo
17.
Chem Commun (Camb) ; (6): 613-5, 2007 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-17264908

RESUMEN

The chiral diphosphinite ligand derived from (R)-1,1'-spirobiindane-7,7'-diol has been found to be highly effective in the Ir-catalyzed asymmetric hydrogenation of quinolines with high substrate/catalyst ratio (up to 5000) and high enantioselectivity (up to 94% ee).

18.
Am J Chin Med ; 35(6): 937-45, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18186580

RESUMEN

In this study, 4 male Qigong masters (aged 60 +/- 12) who had Qigong practicing experience for more than 30 years were tested. By using the technique of fMRI, the change of brain function under the state of Qigong was observed through the peripheral pain stimulation generated by potassium penetrating method. The fMRI examination was running on a GE signa VH/3.0 T MRI machine and block design was used. The test was repeated several times, which was carried out before and 15 min after Qigong practicing. The heart and respiration rate of these 4 Qigong masters were monitored during the whole test. SPM2 was used for the data analysis, and the result showed that before Qigong practicing, besides SI and SII-insula regions, many other Brodmann areas, the cigulate cortex, the thalamus, and the cerebellum were all activated, while 15 min after that, the activated areas were decreased obviously, which were mainly at the SII-insula region and some other Brodmann areas. Since the SII-insula region was activated in both of these two states, further analysis of the response curve was focused on it. Its response amplitude under the state of Qigong (3.5%) was greater than that before Qigong (1.2%). Our result indicated that the main manifestation of brain functional change under Qigong was functional suppressing, but in some particular regions such as SII-insula region in our study, the response amplitude was increased. Further study of the exact physiological mechanism of Qigong is needed.


Asunto(s)
Encéfalo/fisiopatología , Ejercicios Respiratorios , Umbral del Dolor/fisiología , Dolor/fisiopatología , Anciano , Encéfalo/patología , Mapeo Encefálico , Cerebelo/patología , Cerebelo/fisiopatología , Frecuencia Cardíaca/fisiología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Dolor/patología , Respiración , Tálamo/patología , Tálamo/fisiopatología
19.
Acupunct Electrother Res ; 32(3-4): 179-93, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18494380

RESUMEN

The purpose of this study was to investigate the neuronal specificity of needling acupoints at same meridian by functional Magnetic Resonance Imaging (fMRI). The selected acupoints GB34 (Yanglinquan) and GB39 (Xuanzhong) were at the same gallbladder meridian based on traditional Chinese medicine. In our study we devise three distinct EA (electroacupuncture) manipulations: real EA (deep needling at acupoints), sham EA (deep needling at no-meridian points) and shallow EA (subcutaneous needling at acupoints). Twelve healthy volunteers with right-handiness were enrolled and received three different EA manipulations in counter-balanced orders. DeQi scores were used to evaluate the degree of needling sensation. We found real EA can induce significant stronger needling sensation than sham EA and shallow EA. Multisubjects group mean analysis showed that pain-related cortex including primary and secondary somatosensory cortex (SI and S II), anterior cingulated cortex (ACC), insula were involved in three EA stimulation. Bilateral activation of prefrontal gyrus and occipital cortex were exclusively found in real EA. Deactivation over the rostral segment of ACC was also shown in real and shallow EA. Further paired two difference analysis indicated that real EA induced higher activation than sham EA over bilateral prefrontal gyrus, right-side occipital gyrus and deactivation over the rostral segment of ACC. In the comparing with real EA versus shallow EA, there was right-side activation over the SI, S II, motor cortex, ACC, insula, thalamus, hippocampus, occipital cortex, and cerebellum; also activation over bilateral prefrontal gyrus, caudate and pons. Although no significant activation was found over periaqueductal gray (PAG), further analysis showed the mean and maximal signal changes were different under three EA manipulations. We concluded that EA at analgesic acupoints of same meridian maybe involved the pain-related neuromatrix especially the hypothalamus-limbic system; deep EA at meridian points could elicit stronger needling sensation and modulate the pain-related neuromatrix more effectively than EA at nonmeridian points or shallow EA at meridian points.


Asunto(s)
Puntos de Acupuntura , Electroacupuntura , Imagen por Resonancia Magnética/métodos , Meridianos , Adulto , Corteza Cerebral/fisiología , Femenino , Humanos , Masculino , Sustancia Gris Periacueductal/fisiología , Sensación
20.
Zhonghua Yi Xue Za Zhi ; 87(27): 1894-9, 2007 Jul 17.
Artículo en Zh | MEDLINE | ID: mdl-17923012

RESUMEN

OBJECTIVE: To investigate whether a large-scale visual network and visual consciousness are still retained in the patients with minimally conscious state (MCT) and the possibility of promoting the rehabilitation of brain function by visual stimulation. METHODS: Fifteen standardized pictures provided by the International Affective Picture System (IAPS2005) were passively presented to 10 normal adult controls and 9 patients in MCT recovering from severe craniocerebral injury or cerebral hemorrhage. Functional magnetic imaging was conducted. The AFNI software was used to process the images thus collected. RESULTS: The primary visual cortex, occipital lobe, and the secondary visual cortexes, including temporal lobe, parietal lobe, fusiform gyrus, orbital gyrus, and prefrontal lobe were all activated in the 10 normal persons. Similar visual activation was found in 2 of the patients in MCS, however, with a smaller activation volume. Activation of partial visual network was found in 3 patients and the other 4 failed to be activated. CONCLUSION: It is feasible to promote the rehabilitation of brain function by visual stimulation in the patients in MCS.


Asunto(s)
Encefalopatías/fisiopatología , Corteza Cerebral/fisiopatología , Imagen por Resonancia Magnética/métodos , Corteza Visual/fisiopatología , Adulto , Encefalopatías/psicología , Corteza Cerebral/fisiología , Estado de Conciencia , Estudios de Factibilidad , Humanos , Masculino , Estimulación Luminosa/métodos , Corteza Visual/fisiología , Percepción Visual/fisiología
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