13 research outputs found

    Changes in facial fat in lipodystrophy, wasting and weight gain measured by magnetic resonance imaging

    Get PDF
    Background: Changes in facial fat occurring over time in patients with HIV-related lipoatrophy have not been properly quantified. We aimed to define the longitudinal changes in facial fat compartments in patients with lipoatrophy and to compare these with changes accompanying wasting or weight gain. Method: Facial MRI scans were performed at baseline and repeated after a median of 10 months in 24 patients, of whom 12 had moderate to severe lipodystrophy continuing antiretroviral therapy, 5 lost weight, and 7 gained weight (more than 10% weight change). Results: Superficial facial fat decreased by a median of 5.2 mL (p = .03) in patients with lipoatrophy, and 8 of 12 individuals showed more than 15% decrease (all of whom were taking stavudine). The decrease was mainly cheek fat. Superficial facial fat decreased by 6.0 mL in patients with weight loss (p = .04) and increased by 20.2 mL (p = .02) in patients with weight gain, and changes occurred in cheek fat, temporal fat, and masseter muscle and temporalis muscle compartments. Conclusion: MRI can detect substantial ongoing changes in facial fat in patients with facial lipoatrophy. A characteristic pattern of compartmental change distinguishes lipoatrophy from wasting and weight recovery. MRI should be considered for use in clinical trials of interventions to prevent or treat lipoatrophy and may be useful for documenting changes in individual patients during clinical follow-up. Changes in facial fat occurring over time in patients with HIV-related lipoatrophy have not been properly quantified. We aimed to define the longitudinal changes in facial fat compartments in patients with lipoatrophy and to compare these with changes accompanying wasting or weight gain. Facial MRI scans were performed at baseline and repeated after a median of 10 months in 24 patients, of whom 12 had moderate to severe lipodystrophy continuing antiretroviral therapy, 5 lost weight, and 7 gained weight (more than 10% weight change). Superficial facial fat decreased by a median of 5.2 mL (p = .03) in patients with lipoatrophy, and 8 of 12 individuals showed more than 15% decrease (all of whom were taking stavudine). The decrease was mainly cheek fat. Superficial facial fat decreased by 6.0 mL in patients with weight loss (p = .04) and increased by 20.2 mL (p = .02) in patients with weight gain, and changes occurred in cheek fat, temporal fat, and masseter muscle and temporalis muscle compartments. MRI can detect substantial ongoing changes in facial fat in patients with facial lipoatrophy. A characteristic pattern of compartmental change distinguishes lipoatrophy from wasting and weight recovery. MRI should be considered for use in clinical trials of interventions to prevent or treat lipoatrophy and may be useful for documenting changes in individual patients during clinical follow-up

    Associations of hippocampal subfields in the progression of cognitive decline related to Parkinson's disease.

    Get PDF
    OBJECTIVE: Hippocampal atrophy has been associated with mild cognitive impairment (MCI) in Parkinson's disease (PD). However, literature on how hippocampal atrophy affects the pathophysiology of cognitive impairment in PD has been limited. Previous studies assessed the hippocampus as an entire entity instead of their individual subregions. We studied the progression of cognitive status in PD subjects over 18 in relation to hippocampal subfields atrophy. METHODS: 65 PD subjects were included. Using the MDS task force criteria, PD subjects were classified as either having no cognitive impairment (PD-NCI) or PD-MCI. We extended the study by investigating the hippocampal subfields atrophy patterns in those who converted from PD-NCI to PD-MCI (PD-converters) compared to those who remained cognitively stable (PD-stable) over 18 months. Freesurfer 6.0 was used to perform the automated segmentation of the hippocampus into thirteen subregions. RESULTS: PD-MCI showed lower baseline volumes in the left fimbria, right CA1, and right HATA; and lower global cognition scores compared to PD-NCI. Baseline right CA1 was also correlated with baseline attention. Over 18 months, decline in volumes of CA2-3 and episodic memory were also seen in PD-converters compared to PD-stable. Baseline volumes of GC-DG, right CA4, left parasubiculum, and left HATA were predictive of the conversion from PD-NCI to PD-MCI. CONCLUSION: The findings from this study add to the anatomical knowledge of hippocampal subregions in PD, allowing us to understand the unique functional contribution of each subfield. Structural changes in the hippocampus subfields could be early biomarkers to detect cognitive impairment in PD

    Levodopa and the feedback process on set-shifting in Parkinson's disease

    No full text
    To study the interaction between levodopa and the feedback process on set-shifting in Parkinson's disease (PD). Methods: Functional magnetic resonance imaging (fMRI) studies were performed on 13 PD subjects and 17 age-matched healthy controls while they performed a modified card-sorting task. Experimental time periods were defined based on the types of feedback provided. PD subjects underwent the fMRI experiment twice, once during “off” medication (PDoff) and again after levodopa replacement (PDon). Results: Compared with normal subjects, the cognitive processing times were prolonged in PDoff but not in PDon subjects during learning through positive outcomes. The ability to set-shift through negative outcomes was not affected in PD subjects, even when “off” medication. Intergroup comparisons showed the lateral prefrontal cortex was deactivated in PDoff subjects during positive feedback learning, especially following internal feedback cues. The cortical activations were increased in the posterior brain regions in PDoff subjects following external feedback learning, especially when negative feedback cues were provided. Levodopa replacement did not completely restore the activation patterns in PD subjects to normal although activations in the corticostriatal loops were restored. Conclusion: PD subjects showed differential ability to set-shift, depending on the dopamine status as well as the types of feedback cues provided. PD subjects had difficulty performing set-shift tasks through positive outcomes when “off” medication, and showed improvement after levodopa replacement. The ability to set-shift through negative feedback was not affected in PD subjects even when “off” medication, possibly due to compensatory changes outside the nigrostriatal dopaminergic pathway

    Neurocysticercosis Diagnosed by Taenia solium PCR on Brain Biopsy

    No full text
    Neurocysticercosis is a common cause for brain lesions and adult-onset epilepsy in endemic countries. However, diagnosis is challenging in the absence of typical radiologic or histopathologic features. In this case report, we present a case of a 35-year-old male with a new-onset seizure and a rim-enhancing temporal lobe lesion. Radiologic features were nonspecific, and brain biopsy was performed. Histologic features showed only nonspecific granulomatous inflammation, and the diagnosis of neurocysticercosis was confirmed only with polymerase chain reaction (PCR) testing on brain biopsy tissue demonstrating PCR products consistent with Taenia solium. This case highlights the diagnostic role of PCR in such clinical situations whereby the diagnosis is unclear after initial routine evaluation

    A roadmap towards pollution prevention and sustainable development of Gadolinium

    No full text
    International audienceSeveral studies have shown the evidence of GBCAs’environmentalpollution and Gd3+toxicity both in aquatic organisms and humans. This short communication provides a roadmap using recent quan-titative data on GBCAs’consumption, medical use and waste, towardsenvironmental pollution mitigation and sustainable developmen

    GRIN2B Gene and Associated Brain Cortical White Matter Changes in Bipolar Disorder: A Preliminary Combined Platform Investigation

    Get PDF
    Abnormalities in glutamate signaling and glutamate toxicity are thought to be important in the pathophysiology of bipolar disorder (BD). Whilst previous studies have found brain white matter changes in BD, there is paucity of data about how glutamatergic genes affect brain white matter integrity in BD. Based on extant neuroimaging data, we hypothesized that GRIN2B risk allele is associated with reductions of brain white matter integrity in the frontal, parietal, temporal, and occipital regions and cingulate gyrus in BD. Fourteen patients with BD and 22 healthy controls matched in terms of age, gender and handedness were genotyped using blood samples and underwent diffusion tensor imaging. Compared to G allele, brain FA values were significantly lower in BD patients with risk T allele in left frontal region (P=0.001), right frontal region (P=0.002), left parietal region (P=0.001), left occipital region (P=0.001), right occipital region (P<0.001), and left cingulate gyrus (P=0.001). Further elucidation of the interactions between different glutamate genes and their relationships with such structural, functional brain substrates will enhance our understanding of the link between dysregulated glutamatergic neurotransmission and neuroimaging endophenotypes in BD
    corecore