Aberrant dentato-rubro-thalamic pathway in action tremor but not rest tremor: A multi-modality magnetic resonance imaging study.

AIMS: The purpose of this study was to clarify the dentato-rubro-thalamic (DRT) pathway in action tremor in comparison to normal controls (NC) and disease controls (i.e., rest tremor) by using multi-modality magnetic resonance imaging (MRI). METHODS: This study included 40 essential tremor (ET) patients, 57 Parkinson's disease (PD) patients (29 with rest tremor, 28 without rest tremor), and 41 NC. We used multi-modality MRI to comprehensively assess major nuclei and fiber tracts of the DRT pathway, which included decussating DRT tract (d-DRTT) and non-decussating DRT tract (nd-DRTT), and compared the differences in DRT pathway components between action and rest tremor. RESULTS: Bilateral dentate nucleus (DN) in the ET group had excessive iron deposition compared with the NC group. Compared with the NC group, significantly decreased mean diffusivity and radial diffusivity were observed in the left nd-DRTT in the ET group, which were negatively correlated with tremor severity. No significant difference in each component of the DRT pathway was observed between the PD subgroup or the PD and NC. CONCLUSION: Aberrant changes in the DRT pathway may be specific to action tremor and were indicating that action tremor may be related to pathological overactivation of the DRT pathway.

Current coffee consumption is associated with decreased striatal dopamine transporter availability in Parkinson's disease patients and healthy controls.

BACKGROUND: Coffee is the most widely consumed psychostimulant worldwide. Emerging evidence indicates that coffee consumption habit significantly reduces the risk of developing Parkinson's disease (PD). However, the effect of coffee consumption on nigrostriatal dopaminergic neurodegeneration is still largely unknown. We therefore aim to investigate the role of coffee consumption in nigrostriatal dopaminergic neurodegeneration using dopamine transporter (DAT) imaging in PD and healthy controls (HC). METHODS: A total of 138 PD patients and 75 HC with questionnaires about coffee consumption, and DAT scans were recruited from the Parkinson's Progression Markers Initiative cohort. Demographic, clinical, and striatal DAT characteristics were compared across subgroups of current, former, and never coffee consumers in PD and HC, respectively. Furthermore, partial correlation analyses were performed to determine whether there was a relationship between coffee cups consumed per day and striatal DAT characteristics in each striatal region. In addition, the factors that may have influenced the loss of nigrostriatal dopaminergic neurons were included in multiple linear regression analyses to identify significant contributing factors to DAT availability in each striatal region. RESULTS: PD patients had lower DAT availability in each striatal region than HC (p < 0.001). In PD patients, there were significant differences in DAT availability in the caudate (p = 0.008, Bonferroni corrected) across three PD subgroups. Specifically, post hoc tests showed that current coffee consumers had significantly lower DAT availability in the caudate than former coffee consumers (p = 0.01) and never coffee consumers (p = 0.022). In HC, there were significant differences in DAT availability in the caudate (p = 0.031, Bonferroni uncorrected) across three HC subgroups. Specifically, post hoc tests showed that current coffee consumers had significantly lower DAT availability in the caudate than former coffee consumers (p = 0.022). Moreover, correlation analysis revealed that cups per day were negatively correlated with DAT availability in the caudate in current consumers of PD patients (r = - 0.219, p = 0.047). In addition, multiple linear regression analyses showed that current coffee consumption remained an independent predictor of decreased DAT availability in the caudate in PD patients and HC. CONCLUSIONS: This study demonstrates that current coffee consumption is associated with decreased striatal DAT availability in the caudate. However, the effects of caffeine on striatal DAT may fade and disappear after quitting coffee consumption. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01141023.

Association of coffee consumption and striatal volume in patients with Parkinson's disease and healthy controls.

BACKGROUND: Mounting studies have demonstrated that coffee consumption significantly reduces the risk of developing Parkinson's disease (PD). However, there have been few investigations about the role of chronic coffee consumption in nigrostriatal structural neurodegeneration in PD. We aimed to investigate whether chronic coffee consumption is associated with the change in striatal volume in PD. METHODS: In this study, 130 de novo patients with PD and 69 healthy controls were enrolled from the Parkinson's Progression Markers Initiative cohort. Patients with PD and healthy controls were, respectively, divided into three subgroups, including current, ever, and never coffee consumers. Then, striatal volume was compared across the three subgroups. Correlation analyses were performed to assess the relationship between cups consumed per day and striatal volume. Furthermore, we included the factors that may have influenced nigrostriatal dopaminergic neurons in multiple linear regression analyses to identify significant contributing factors to striatal volume in each investigated striatal region. RESULTS: Current coffee consumers had decreased striatal volume compared with ever consumers in controls but not patients with PD. Furthermore, the correlation analyses revealed that cups per day were negatively correlated with striatal volume in current consumers of patients with PD and controls. In addition, multiple linear regression analyses showed that current coffee consumption remained as an independent predictor of a decrease in striatal volume in controls. CONCLUSIONS: Our study showed that chronic coffee consumption was negatively correlated with striatal volume. In addition, our study showed that chronic coffee consumption was associated with the change in striatal volume in current-rather than ever coffee consumers, which suggests that the chronic effects of caffeine on striatal morphology may fade and even compensate after quitting coffee. Our study provides evidence for the effect of chronic coffee consumption on striatal volume in human brain in vivo.

Hair Se Is a Sensitive Biomarker to Monitor the Effects of Se Supplementation in Elderly.

It is rapidly increasing to have selenium (Se) supplementation for urban elderly population in China since they are facing a widespread deficiency daily Se intake. However, until now, there is no low-cost, non-invasive, rapid, and reliable method to monitor the health improvement or risk for elderly Se-supplemented population in China. The present cross-sectional study (229 participants with older than 55 years old) performed in Beijing, China, revealed that the Se concentrations of non-supplementer users (n = 27) were 55 ± 23 µg/L in urine, 139.9 ± 102.3 µg/L in serum, and 487.6 ± 158.7 µg/kg in hair. But a significant increase on hair Se concentrations (615.4 ± 238.8 µg/kg) was observed for Se supplementer users (n = 202) (p < 0.05); there were no significant statistical differences in serum and urine between the Se-supplemented (n = 202) and Se non-supplemented groups (n = 27). This indicated the hair Se levels could be a more sensitive biomarker for Se-supplemented elderly population. Participants who consumed Se supplements for 7-12 months had the highest Se status based on hair and serum Se concentrations (p < 0.05). The present study also revealed that most elderly adults in Beijing just need to supplement 50 µg Se per day to achieve Se plateau status. Furthermore, hair Se levels were positively related with triglycerides/TG levels (p < 0.05) but not body mass index/BMI, total cholesterol/TC, and low-density lipoprotein cholesterol/LDL, implicating Se supplementation for Se sufficiency baseline in elderly population in Beijing likely posed health risk, especially on TG because of excessive Se oxidation stress. An ongoing monitoring of Se status via hair is still warranted to prevent future Se deficiency or excess in China.

Progressive microstructural alterations in subcortical nuclei in Parkinson's disease: A diffusion magnetic resonance imaging study.

OBJECTIVES: To explore the microstructural alterations in subcortical nuclei in Parkinson's disease (PD) at different stages with diffusion kurtosis imaging (DKI) and tensor imaging and to test the performance of diffusion metrics in identifying PD. METHODS: 108 PD patients (64 patients in early-stage PD group (EPD) and 44 patients in moderate-late-stage PD group (MLPD)) and 64 healthy controls (HC) were included. Tensor and kurtosis metrics in the subcortical nuclei were compared. Partial correlation was used to correlate the diffusion metrics and Unified Parkinson's Disease Rating Scale part-III (UPDRS-III) score. Logistic regression and receiver operating characteristic analysis were applied to test the diagnostic performance of the diffusion metrics. RESULTS: Compared with HC, both EPD and MLPD patients showed higher fractional anisotropy and axial diffusivity, lower mean kurtosis (MK) and axial kurtosis in substantia nigra, lower MK and radial kurtosis (RK) in globus pallidus (GP) and thalamus (all p < 0.05). Compared with EPD, MLPD patients showed lower MK and RK in GP and thalamus (all p < 0.05). MK and RK in GP and thalamus were negatively correlated with UPDRS-III score (all p < 0.01). The logistic regression model combining kurtosis and tensor metrics showed the best performance in diagnosing PD, EPD, and MLPD (areas under curve were 0.817, 0.769, and 0.914, respectively). CONCLUSIONS: PD has progressive microstructural alterations in the subcortical nuclei. DKI is sensitive to detect microstructural alterations in GP and thalamus during PD progression. Combining kurtosis and tensor metrics can achieve a good performance in diagnosing PD.

Increased thalamic volume and decreased thalamo-precuneus functional connectivity are associated with smoking relapse.

The thalamus, with the highest density of nicotinic acetylcholine receptor (nAChR) in the brain, plays a central role in thalamo-cortical circuits that are implicated in nicotine addiction. However, little is known about whether the thalamo-cortical circuits are potentially predictive of smoking relapse. In the current study, a total of 125 participants (84 treatment-seeking male smokers and 41 age-matched male nonsmokers) were recruited. Structural and functional magnetic resonance images (MRI) were acquired from all participants. After a 12-week smoking cessation treatment with varenicline, the smokers were then divided into relapsers (n = 54) and nonrelapsers (n = 30). Then, we compared thalamic volume and seed-based thalamo-cortical resting state functional connectivity (rsFC) prior to the cessation treatment among relapsers, nonrelapsers and nonsmokers to investigate the associations between thalamic structure/function and smoking relapse. Increased thalamic volume was detected in smokers relative to nonsmokers, and in relapsers relative to nonrelapsers, especially on the left side. Moreover, decreased left thalamo-precuneus rsFC was detected in relapsers relative to nonrelapsers. Additionally, a logistic regression analysis showed that the thalamic volume and thalamo-precuneus rsFC predicted smoking relapse with an accuracy of 75.7%. These novel findings indicate that increased thalamic volume and decreased thalamo-precuneus rsFC are associated with smoking relapse, and these thalamic measures may be used to predict treatment efficacy of nicotine addiction and serve as a potential biomarker for personalized medicine.

Biodegradable Hollow Mesoporous Organosilica Nanotheranostics for Mild Hyperthermia-Induced Bubble-Enhanced Oxygen-Sensitized Radiotherapy.

Alleviation of tumor hypoxia has been the premise for improving the effectiveness of radiotherapy, which hinges upon the advanced delivery and rapid release of oxygen within the tumor region. Herein, we propose a "bubble-enhanced oxygen diffusion" strategy to achieve whole tumor oxygenation for significant radiation enhancement based on the "bystander effect". Toward this end, sub-50 nm CuS-modified and 64Cu-labeled hollow mesoporous organosilica nanoparticles were constructed for tumor-specific delivery of O2-saturated perfluoropentane (PFP). Through the aid of PFP gasification arising from NIR laser-triggered mild hyperthermia, simultaneous PET/PA/US multimodality imaging and rapid oxygen diffusion across the tumor can be achieved for remarkable hypoxic radiosensitization. Furthermore, the multifunctional oxygen-carrying nanotheranostics also allow for other oxygen-dependent treatments, thus greatly advancing the development of bubble-enhanced synergistic therapy platforms.

Localized shape abnormalities in the thalamus and pallidum are associated with secondarily generalized seizures in mesial temporal lobe epilepsy.

Mesial temporal lobe epilepsy (mTLE) is a common type of drug-resistant epilepsy and secondarily generalized tonic-clonic seizures (sGTCS) have devastating consequences for patients' safety and quality of life. To probe the mechanism underlying the genesis of sGTCS, we investigated the structural differences between patients with and without sGTCS in a cohort of mTLE with radiologically defined unilateral hippocampal sclerosis. We performed voxel-based morphometric analysis of cortex and vertex-wise shape analysis of subcortical structures (the basal ganglia and thalamus) on MRI of 39 patients (21 with and 18 without sGTCS). Comparisons were initially made between sGTCS and non-sGTCS groups, and subsequently made between uncontrolled-sGTCS and controlled-sGTCS subgroups. Regional atrophy of the ipsilateral ventral pallidum (cluster size=450 voxels, corrected p=0.047, Max voxel coordinate=107, 120, 65), medial thalamus (cluster size=1128 voxels, corrected p=0.049, Max voxel coordinate=107, 93, 67), middle frontal gyrus (cluster size=60 voxels, corrected p<0.05, Max voxel coordinate=-30, 49.5, 6), and contralateral posterior cingulate cortex (cluster size=130 voxels, corrected p<0.05, Max voxel coordinate=16.5, -57, 27) was found in the sGTCS group relative to the non-sGTCS group. Furthermore, the uncontrolled-sGTCS subgroup showed more pronounced atrophy of the ipsilateral medial thalamus (cluster size=1240 voxels, corrected p=0.014, Max voxel coordinate=107, 93, 67) than the controlled-sGTCS subgroup. These findings indicate a central role of thalamus and pallidum in the pathophysiology of sGTCS in mTLE.

Increased thalamic centrality and putamen-thalamic connectivity in patients with parkinsonian resting tremor.

INTRODUCTION: Evidence has indicated a strong association between hyperactivity in the cerebello-thalamo-motor cortical loop and resting tremor in Parkinson's disease (PD). Within this loop, the thalamus serves as a central hub based on its structural centrality in the generation of resting tremor. To study whether this thalamic abnormality leads to an alteration at the whole-brain level, our study investigated the role of the thalamus in patients with parkinsonian resting tremor in a large-scale brain network context. METHODS: Forty-one patients with PD (22 with resting tremor, TP and 19 without resting tremor, NTP) and 45 healthy controls (HC) were included in this resting-state functional MRI study. Graph theory-based network analysis was performed to examine the centrality measures of bilateral thalami across the three groups. To further provide evidence to the central role of the thalamus in parkinsonian resting tremor, the seed-based functional connectivity analysis was then used to quantify the functional interactions between the basal ganglia and the thalamus. RESULTS: Compared with the HC group, patients with the TP group exhibited increased degree centrality (p < .04), betweenness centrality (p < .01), and participation coefficient (p < .01) in the bilateral thalami. Two of these alterations (degree centrality and participation coefficient) were significantly correlated with tremor severity, especially in the left hemisphere (p < .02). The modular analysis showed that the TP group had more intermodular connections between the thalamus and the regions within the cerebello-thalamo-motor cortical loop. Furthermore, the data revealed significantly enhanced functional connectivity between the putamen and the thalamus in the TP group (p = .027 corrected for family-wise error). CONCLUSIONS: These findings suggest increased thalamic centrality as a potential tremor-specific imaging measure for PD, and provide evidence for the altered putamen-thalamic interaction in patients with resting tremor.

Hepatic sinusoidal obstruction syndrome caused by herbal medicine: CT and MRI features.

OBJECTIVE: To describe the CT and MRI features of hepatic sinusoidal obstruction syndrome (HSOS) caused by herbal medicine Gynura segetum. MATERIALS AND METHODS: The CT and MRI features of 16 consecutive Gynura segetum induced HSOS cases (12 men, 4 women) were analyzed. Eight patients had CT; three patients had MRI, and the remaining five patients had both CT and MRI examinations. Based on their clinical presentations and outcomes, the patients were classified into three categories: mild, moderate, and severe. The severity of the disease was also evaluated radiologically based on the abnormal hepatic patchy enhancement in post-contrast CT or MRI images. RESULTS: Ascites, patchy liver enhancement, and main right hepatic vein narrowing or occlusion were present in all 16 cases. Hepatomegaly and gallbladder wall thickening were present in 14 cases (87.5%, 14/16). Periportal high intensity on T2-weighted images was present in 6 cases (75%, 6/8). Normal liver parenchymal enhancement surrounding the main hepatic vein forming a clover-like sign was observed in 4 cases (25%, 4/16). The extent of patchy liver enhancement was statistically associated with clinical severity classification (kappa = 0.565). CONCLUSION: Ascites, patchy liver enhancement, and the main hepatic veins narrowing were the most frequent signs of herbal medicine induced HSOS. The grade of abnormal patchy liver enhancement was associated with the clinical severity.

Xueshuantong improves cerebral blood perfusion in elderly patients with lacunar infarction.

A total of 64 patients with acute lacunar infarction were enrolled within 24 hours of onset. The patients received conventional therapy (antiplatelet drugs and hypolipidemic drugs) alone or conventional therapy plus 450 mg Xueshuantong once a day. The main ingredient of the Xueshuantong lyophilized powder used for injection was Panax notoginseng saponins. Assessments were made at admission and at discharge using the National Institutes of Health Stroke Scale, the Activity of Daily Living and the Mini-Mental State Examination. Additionally, the relative cerebral blood flow, relative cerebral blood volume and relative mean transit time in the region of interest were calculated within 24 hours after the onset of lacunar infarction, using dynamic susceptibility contrast magnetic resonance perfusion imaging technology. Patients underwent a follow-up MRI scan after 4 weeks of treatment. There was an improvement in the Activity of Daily Living scores and a greater reduction in the scores on the National Institutes of Health Stroke Scale in the treatment group than in the control group. However, the Mini-Mental State Examination scores showed no significant differences after 4 weeks of treatment. Compared with the control group, the relative cerebral blood flow at discharge had increased and showed a greater improvement in the treatment group. Furthermore, there was a reduction in the relative mean transit time at discharge and the value was lower in the treatment group than in the control group. The experimental findings indicate that Xueshuantong treatment improves neurological deficits in elderly patients with lacunar infarction, and the mechanism may be related to increased cerebral perfusion.

[Biochemical metabolic changes detected by phosphorus-31 MR spectroscopy in liver of fasting rabbits].

OBJECTIVE: To investigate the biochemical metabolic changes detected by phosphorus-31 MR spectroscopy ((31)P MRS) with pathologic changes in the liver of fasting rabbits. METHODS: A total of 22 rabbits were under the starvation up to death to establish animal models. Hepatic (31)P MRS was performed in different period of 10 rabbits including normal condition, over-starvation, agonal condition and death after 30 min. Other 9 rabbits were divided into three type including over-starvation, agonal condition and death group with 3 rabbits in each group, and 3 healthy rabbits served as controls. All the 12 rabbits were sacrificed for the hepatic pathological examination. The MR examination was performed on a 1.5 T imager using a 1H/31P surface coil by the 2D chemical shift imaging technique. The relative quantities of phosphomonoesters (PME), phosphodiesters (PDE), inorganic phosphate (Pi) and adenosine triphosphate (ATP) were measured. RESULTS: All the relative quantification of phosphorus metabolites were changed significantly from starvation to death (X(2)=23.13-35.41, P<0.01). The relative quantifications of ATP of normal condition, over-starvation, agonal condition and death were 2.54 +/-0.53, 1.73 +/-0.14, 0.88 +/-0.23 and 0.05 +/-0.08, respectively (rs=1.0, P<0.01). The relative quantifications of PDE from normal to death were 1.25 +/-0.54, 2.76 +/-0.23, 3.33 +/-0.49 and 3.87 +/-0.43, respectively, and those of Pi were 0.42 +/-0.02, 0.65 +/-0.05, 0.89 +/-0.15 and 0.99 +/-0.08, respectively (rs=1.0, P <0.01). The relative quantifications of PME were also significantly changed (rs=0.4, P=0.6). The pathologic changes of normal condition, over-starvation, agonal condition and death: decreased size of hepatocytes, loss of cell number, cellular swelling, degeneration and cell necrosis or hepatic hemorrhage became more and more pronounced. CONCLUSION: (31)P MRS can monitor dynamic changes of relative quantification of phosphorus metabolites, which are correlated with the pathological severity of acute hepatic injury by fasting.

Multisensory cortical processing of object shape and its relation to mental imagery.

Here, we used functional magnetic resonance imaging to investigate the multisensory processing of object shape in the human cerebral cortex and explored the role of mental imagery in such processing. Regions active bilaterally during both visual and haptic shape perception, relative to texture perception in the respective modality, included parts of the superior parietal gyrus, the anterior intraparietal sulcus, and the lateral occipital complex. Of these bimodal regions, the lateral occipital complexes preferred visual over haptic stimuli, whereas the parietal areas preferred haptic over visual stimuli. Whereas most subjects reported little haptic imagery during visual shape perception, experiences of visual imagery during haptic shape perception were common. Across subjects, ratings of the vividness of visual imagery strongly predicted the amount of haptic shape-selective activity in the right, but not in the left, lateral occipital complex. Thus, visual imagery appears to contribute to activation of some, but not all, visual cortical areas during haptic perception.