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The pharmacological perturbation of brain zinc impairs BDNF-related signaling and the cognitive performances of young mice.
Zinc (Zn2+) is a pleiotropic modulator of the neuronal and brain activity. The disruption of intraneuronal Zn2+ levels triggers neurotoxic processes and affects neuronal functioning. In this study, we investigated how the pharmacological modulation of brain Zn2+ affects synaptic plasticity and cognition in wild-type mice. To manipulate brain Zn2+ levels, we employed the Zn2+ (and copper) chelator 5-chloro-7-iodo-8-hydroxyquinoline (clioquinol, CQ). CQ was administered for two weeks to 2.5-month-old (m.o.) mice, and effects studied on BDNF-related signaling, metalloproteinase activity as well as learning and memory performances. CQ treatment was found to negatively affect short- and long-term memory performances. The CQ-driven perturbation of brain Zn2+ was found to reduce levels of BDNF, synaptic plasticity-related proteins and dendritic spine density in vivo. Our study highlights the importance of choosing "when", "where", and "how much" in the modulation of brain Zn2+ levels. Our findings confirm the importance of targeting Zn2+ as a therapeutic approach against neurodegenerative conditions but, at the same time, underscore the potential drawbacks of reducing brain Zn2+ availability upon the early stages of development
A Machine Learning-Based Holistic Approach to Predict the Clinical Course of Patients within the Alzheimer’s Disease Spectrum
Background: Alzheimer’s disease (AD) is a neurodegenerative condition driven by multifactorial etiology. Mild cognitive impairment (MCI) is a transitional condition between healthy aging and dementia. No reliable biomarkers are available to predict the conversion from MCI to AD. Objective: To evaluate the use of machine learning (ML) on a wealth of data offered by the Alzheimer’s Disease Neuroimaging Initiative (ADNI) and Alzheimer’s Disease Metabolomics Consortium (ADMC) database in the prediction of the MCI to AD conversion. Methods: We implemented an ML-based Random Forest (RF) algorithm to predict conversion from MCI to AD. Data related to the study population (587 MCI subjects) were analyzed by RF as separate or combined features and assessed for classification power. Four classes of variables were considered: neuropsychological test scores, AD-related cerebrospinal fluid (CSF) biomarkers, peripheral biomarkers, and structural magnetic resonance imaging (MRI) variables. Results: The ML-based algorithm exhibited 86% accuracy in predicting the AD conversion of MCI subjects. When assessing the features that helped the most, neuropsychological test scores, MRI data, and CSF biomarkers were the most relevant in the MCI to AD prediction. Peripheral parameters were effective when employed in association with neuropsychological test scores. Age and sex differences modulated the prediction accuracy. AD conversion was more effectively predicted in females and younger subjects. Conclusion: Our findings support the notion that AD-related neurodegenerative processes result from the concerted activity of multiple pathological mechanisms and factors that act inside and outside the brain and are dynamically affected by age and sex
Macrostructural Alterations of Subcortical Grey Matter in Psychogenic Erectile Dysfunction
Psychogenic erectile dysfunction (ED) has been defined as the persistent inability to attain and maintain an erection sufficient to permit sexual performance. It shows a high incidence and prevalence among men, with a significant impact on the quality of life. Few neuroimaging studies have investigated the cerebral basis of erectile dysfunctions observing the role played by prefrontal, cingulate, and parietal cortices during erotic stimulation. In spite of the well-known involvement of subcortical regions such as hypothalamus and caudate nucleus in male sexual response, and the key role of nucleus accumbens in pleasure and reward, poor attention was paid to their role in male sexual dysfunction. In this study, we determined the presence of grey matter (GM) atrophy patterns in subcortical structures such as amygdala, hippocampus, nucleus accumbens, caudate nucleus, putamen, pallidum, thalamus, and hypothalamus in patients with psychogenic ED and healthy men. After Rigiscan evaluation, urological, general medical, metabolic and hormonal, psychological and psychiatric assessment, 17 outpatients with psychogenic ED and 25 healthy controls were recruited for structural MRI session. Significant GM atrophy of nucleus accumbens was observed bilaterally in patients with respect to controls. Shape analysis showed that this atrophy was located in the left medial-anterior and posterior portion of accumbens. Left nucleus accumbens volumes in patients correlated with low erectile functioning as measured by IIEF-5 (International Index of Erectile Function). In addition, a GM atrophy of left hypothalamus was also observed. Our results suggest that atrophy of nucleus accumbens plays an important role in psychogenic erectile dysfunction. We believe that this change can influence the motivation-related component of sexual behavior. Our findings help to elucidate a neural basis of psychogenic erectile dysfunction
Classical and Hellenistic statuettes of the so–called “Temple Boys”: A religious and social reappraisal
Classical and Hellenistic statuettes of the so–called “Temple Boys”: A religious and social reappraisal.
peer reviewedOur paper reconsiders the religious and social significance of a corpus of statuettes representing crouching children with jewels and amulets, principally dedicated in shrines on Cyprus from about the mid–fifth century BC down to the Hellenistic period. The most plausible interpretation of these statues, that of votive dedications aiming to evoke divine protection on small children, will be substantiated by discussion of discovery contexts and of the significance of amulets and other objects decorating these statues, as well as by broader considerations on the place of small children in temples. The variety of configurations of these statues will also be taken into account in order to discuss the possibility of various interpretations instead of one single interpretative paradigm
Transplantation of Mesenchymal Cells Improves Peripheral Limb Ischemia in Diabetic Rats
Adipose tissue-derived mesenchymal stromal cells (ADSCs) are a prominent cellular source for regenerative medicine. We tested whether transplantation of ADSCs into the ischemic muscular tissue of diabetic animals would attenuate impaired cell metabolism and microcirculatory function. We induced unilateral hind limb ischemia in male streptozotocin-treated rats and nondiabetic controls. One day after femoral artery ligation, six rats per group were intramuscularly injected allogeneic ADSCs (10(6)-10(7)-10(8) cells/mL); or conditioned media from ADSC cultures (CM); or saline; or allogeneic fibroblasts (10(7) cells/mL); or nonconditioned medium. Rats underwent magnetic resonance angiography; short time inversion recovery (STIR) edema-weighed imaging; proton MR spectroscopy ((1)H-MRS); immunoblotting and immunofluorescence on both hind limbs for 4 weeks. T1-weighted and STIR images showed tissue swelling and signal hyperintensity, respectively, in the ischemic tissue. The mean total ratio of creatine/water for the occluded limbs was significantly lower than for the nonoccluded limbs in both nondiabetic and diabetic rats. ADSC and CM groups had greater recovery of tCr/water in ischemic limbs in both diabetic and nondiabetic rats, with increased expression of α-sarcomeric actinin, vascular endothelial growth factor and hepatocyte growth factor, as well as increased vessel density. ADSCs improve ischemic muscle metabolism and increase neovasculogenesis in diabetic rats
Structural alteration of the dorsal visual network in DLB patients with visual hallucinations: a cortical thickness MRI study.
Visual hallucinations (VH) represent one of the core features in discriminating dementia with Lewy bodies (DLB) from Alzheimer's Disease (AD). Previous studies reported that in DLB patients functional alterations of the parieto-occipital regions were correlated with the presence of VH. The aim of our study was to assess whether morphological changes in specific cortical regions of DLB could be related to the presence and severity of VH. We performed a cortical thickness analysis on magnetic resonance imaging data in a cohort including 18 DLB patients, 15 AD patients and 14 healthy control subjects. Relatively to DLB group, correlation analysis between the cortical thickness and the Neuropsychiatric Inventory (NPI) hallucination item scores was also performed. Cortical thickness was reduced bilaterally in DLB compared to controls in the pericalcarine and lingual gyri, cuneus, precuneus, superior parietal gyrus. Cortical thinning was found bilaterally in AD compared to controls in temporal cortex including the superior and middle temporal gyrus, part of inferior temporal cortex, temporal pole and insula. Inferior parietal and supramarginal gyri were also affected bilaterally in AD as compared to controls. The comparison between DLB and AD evidenced cortical thinning in DLB group in the right posterior regions including superior parietal gyrus, precuneus, cuneus, pericalcarine and lingual gyri. Furthermore, the correlation analysis between cortical thickness and NPI hallucination item scores showed that the structural alteration in the dorsal visual regions including superior parietal gyrus and precuneus closely correlated with the occurrence and severity of VH. We suggest that structural changes in key regions of the dorsal visual network may play a crucial role in the physiopathology of VH in DLB patients
Combined 3 Tesla MRI biomarkers improve the differentiation between benign vs malignant single ring enhancing brain masses
conventional and advanced MRI exams raw data of 14 patients affected by metastases, glioblastomas and abscesses
Bioenergetic and functional consequences of adipose tissue-derived stromal cell transplantation on the metabolism of ischemic muscle in a diabetic model
In-vivo assessment of skeletal muscle ischaemia in diabetic rats by MR angiography, MR imaging and proton MR spectroscopy
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