In vitro labeling of human umbilical cord mesenchymal stem cells with superparamagnetic iron oxide nanoparticles.

Human umbilical cord mesenchymal stem cells (hUC-MSCs) transplantation has been shown to promote regeneration and neuroprotection in central nervous system (CNS) injuries and neurodegenerative diseases. To develop this approach into a clinical setting it is important to be able to follow the fates of transplanted cells by noninvasive imaging. Neural precursor cells and hematopoietic stem cells can be efficiently labeled by superparamagnetic iron oxide (SPIO) nanoparticle. The purpose of our study was to prospectively evaluate the influence of SPIO on hUC-MSCs and the feasibility of tracking for hUC-MSCs by noninvasive imaging. In vitro studies demonstrated that magnetic resonance imaging (MRI) can efficiently detect low numbers of SPIO-labeled hUC-MSCs and that the intensity of the signal was proportional to the number of labeled cells. After transplantation into focal areas in adult rat spinal cord transplanted SPIO-labeled hUC-MSCs produced a hypointense signal using T2-weighted MRI in rats that persisted for up to 2 weeks. This study demonstrated the feasibility of noninvasive imaging of transplanted hUC-MSCs.

[CT guided radioactive seed (125)I implantation in treating multiple bone metastasis].

OBJECTIVE: To investigate the clinical value of CT guided radioactive seed (125)I implantation in treating bone metastasis. METHODS: 28 multiple bone metastatic tumor patients with 116 metastatic lesions totally, adenocarcinoma of lung in 6 cases, squamous cell carcinoma of lung, renal clear-cell carcinoma, and carcinoma of prostate in 4 cases each, hepatocellular carcinoma and colon carcinoma in 3 cases each, breast carcinoma in 2 cases, and malignant schwannoma and pancreatic cancer in 1 case each, 13 males and 15 females, aged 49.8, underwent CT guided radioactive seed (125)I implantation into bone metastatic lesions. RESULTS: In these 28 cases, complete pain relief (CR) was observed in 16 cases, partial relief (PR) in 7 cases, and no change (NC) in 5 cases with an effective rate of 82.1%. Among the 116 lesions in these 28 cases local control (LC) was seen in 93 cases, NC in 17, and PD in 6. The response rate was 80.2%. CONCLUSION: CT guided radioactive seed (125)I implantation procedure has good clinical effects in treating bone metastasis with minimal invasive and few complications.

Differential Impairment of Thalamocortical Structural Connectivity in Amyotrophic Lateral Sclerosis.

AIMS: The thalamus is a major relay station that modulates input from many cortical areas and a filter for sensory input and is involved in the pathophysiology of amyotrophic lateral sclerosis (ALS). However, it still remains unclear whether all thalamocortical networks are affected or whether there is selective vulnerability. In this study, we aimed to study the selective vulnerability of different thalamocortical structural connections in ALS and to test the hypothesis of a specific impairment in motor-related thalamocortical connectivity. METHODS: Diffusion tensor imaging (DTI) tractography was used to identify thalamocortical structural pathways in 38 individuals with ALS and 35 gender/age-matched control subjects. Thalami of both groups were parcellated into subregions based on local patterns of thalamocortical connectivity. DTI measures of these distinct thalamocortical connections were derived and compared between groups. RESULTS: The analysis of probabilistic tractography showed that the structural connectivity between bilateral pre/primary motor cortices and associated thalamic subregions was specifically impaired in patients with ALS, while the other thalamocortical connections remained relatively intact. In addition, fractional anisotropy values of the impaired thalamocortical motor pathway were inversely correlated with the disease duration. CONCLUSION: Our findings provide direct evidence for selective impairment of the thalamocortical structural connectivity in ALS.

Memory dysfunction in type 2 diabetes mellitus correlates with reduced hippocampal CA1 and subiculum volumes.

BACKGROUND: Little attention has been paid to the role of subcortical deep gray matter (SDGM) structures in type 2 diabetes mellitus (T2DM)-induced cognitive impairment, especially hippocampal subfields. Our aims were to assess the in vivo volumes of SDGM structures and hippocampal subfields using magnetic resonance imaging (MRI) and to test their associations with cognitive performance in T2DM. METHODS: A total of 80 T2DM patients and 80 neurologically unimpaired healthy controls matched by age, sex and education level was enrolled in this study. We assessed the volumes of the SDGM structures and seven hippocampal subfields on MRI using a novel technique that enabled automated volumetry. We used Mini-Mental State Examination and Montreal Cognitive Assessment (MoCA) scores as measures of cognitive performance. The association of glycosylated hemoglobin (HbA1c) with SDGM structures and neuropsychological tests and correlations between hippocampal subfields and neuropsychological tests were assessed by partial correlation analysis in T2DM. RESULTS: Bilaterally, the hippocampal volumes were smaller in T2DM patients, mainly in the CA1 and subiculum subfields. Partial correlation analysis showed that the MoCA scores, particularly those regarding delayed memory, were significantly positively correlated with reduced hippocampal CA1 and subiculum volumes in T2DM patients. Additionally, higher HbA1c levels were significantly associated with poor memory performance and hippocampal atrophy among T2DM patients. CONCLUSIONS: These data indicate that the hippocampus might be the main affected region among the SDGM structures in T2DM. These structural changes in the hippocampal CA1 and subiculum areas might be at the core of underlying neurobiological mechanisms of hippocampal dysfunction, suggesting that degeneration in these regions could be responsible for memory impairments in T2DM patients.

Amplitude of low-frequency oscillations in Parkinson's disease: a 2-year longitudinal resting-state functional magnetic resonance imaging study.

BACKGROUND: Neuroimaging studies have found that functional changes exist in patients with Parkinson's disease (PD). However, the majority of functional magnetic resonance imaging (fMRI) studies in patients with PD are task-related and cross-sectional. This study investigated the functional changes observed in patients with PD, at both baseline and after 2 years, using resting-state fMRI. It further investigated the relationship between whole-brain spontaneous neural activity of patients with PD and their clinical characteristics. METHODS: Seventeen patients with PD underwent an MRI procedure at both baseline and after 2 years using resting-state fMRI that was derived from the same 3T MRI. In addition, 20 age- and sex-matched, healthy controls were examined using resting-state fMRI. The fractional amplitude of low-frequency fluctuation (fALFF) approach was used to analyze the fMRI data. Nonlinear registration was used to model within-subject changes over the scanning interval, as well as changes between the patients with PD and the healthy controls. A correlative analysis between the fALFF values and clinical characteristics was performed in the regions showing fALFF differences. RESULTS: Compared to the control subjects, the patients with PD showed increased fALFF values in the left inferior temporal gyrus, right inferior parietal lobule (IPL) and right middle frontal gyrus. Compared to the baseline in the 2 years follow-up, the patients with PD presented with increased fALFF values in the right middle temporal gyrus and right middle occipital gyrus while also having decreased fALFF values in the right cerebellum, right thalamus, right striatum, left superior parietal lobule, left IPL, left precentral gyrus, and left postcentral gyrus (P < 0.01, after correction with AlphaSim). In addition, the fALFF values in the right cerebellum were positively correlated with the Unified PD Rating Scale (UPDRS) motor scores (r = 0.51, P < 0.05, uncorrected) and the change in the UPDRS motor score (r = 0.61, P < 0.05, uncorrected). CONCLUSIONS: The baseline and longitudinal changes of the fALFF values in our study suggest that dysfunction in the brain may affect the regions related to cortico-striato-pallido-thalamic loops and cerebello-thalamo-cortical loops as the disease progresses and that alterations to the spontaneous neural activity of the cerebellum may also play an important role in the disease's progression in patients with PD.

Detection of siderotic nodules in the liver with susceptibility weighted imaging: correlations to serum ferritin, Child-Pugh grade and hyaluronic acid levels.

BACKGROUND: Chronic liver disease causes aberrant formation of fibrous tissue that impedes normal liver function, ultimately resulting in liver cirrhosis. Iron uptake can occur within the hepatic parenchyma or within the various nodules that form in a cirrhotic liver, termed siderotic nodules (SN). We aimed to investigate the diagnostic performance of susceptibility weighted imaging (SWI) for detection of SN in patients with liver cirrhosis, and to evaluate the potential of SN numbers for assessing the degree of hepatic iron deposition, liver function, and liver fibrosis stage. METHODS: Ninety-one patients with chronic liver cirrhosis, who underwent megnetic resonance imagine (MRI) scanning in our department between November 2010 and April 2011, were included in the study. A 3.0T MRI scanner was used to acquire T1WI, T2WI, T2WI, and SWI images. The number of nodules, signal intensity ratio (SIR), and contrast noise ratio (CNR) were recorded and analyzed by chi-square and ANOVA statistical tests. Correlation analysis was performed to evaluate the correlations between the number of SN and Child-Pugh classification, ferritin and hyaluronic acid levels. RESULTS: The sensitivity of SWI, T1WI, T2WI, and T2 WI for detecting SN was 62.5%, 12.1%, 24.2% and 41.8%, respectively. SWI detected significantly more nodules than routine T1WI, T2WI, and T2 WI procedures (P < 0.05). The SIR was the lowest in SWI (0.361 ± 0.209), as compared to T1WI (0.852 ± 0.163), T2WI (0.584 ± 0.172), and T2 WI (0.497 ± 0.196). The CNR was the highest in SWI (13.932 ± 5.637), as compared to T1WI (9.147 ± 5.785), T2WI (9.771 ± 5.490), and T2 WI (11.491 ± 4.573). The correlation coefficients of the number of SN with ferritin, Child-Pugh classification, and hyaluronic acid levels were 0.672, -0.055, and 0.163, respectively. CONCLUSIONS: The sensitivity and contrast of SWI for detecting SN in patients with liver cirrhosis are higher than conventional MRI. The number of SN can help to assess the degree of iron deposition in patients with liver cirrhosis.

Spectral-domain optical coherence tomography in patients with congenital nystagmus.

AIM: To study macular features in patients with congenital nystagmus and to assess the utility of spectral-domain optical coherence tomography (SD-OCT) in nystagmus. METHODS: The macular areas of 51 outpatients with congenital nystagmus were examined using SD-OCT. Morphological changes in the retinal layers of the macular area were analysed. RESULTS: Macular images were successfully obtained with SD-OCT from 50 (98%) patients. Patients with ocular albinism mainly have macular hypoplasia, abnormal foveal depression, and increased foveal thickness with persistence of an inner nuclear layer, an inner plexiform layer, a ganglion cell layer and a nerve fiber layer. Macular morphology similar to albinism was observed in three patients with idiopathic macular hypoplasia. The OCT findings of cone dystrophy included unclear, disrupted or invisible photoreceptor outer segment/inner segment in the fovea; fusion, thickening and uneven reflection of the outer segment/inner segment with external limiting membrane. Some patients with congenital idiopathic nystagmus showed normal macular morphology and structure, and others showed indistinct macular external limiting membrane reflection. CONCLUSION: SD-OCT is an effective and reliable method to detect the macular morphology of congenital nystagmus patients. This technique has diagnostic value in particular for patients with macular hypoplasia and cone cell dystrophy with no distinct abnormality on fundoscopy.