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1.
J Cutan Pathol ; 51(7): 485-489, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38549288

ABSTRACT

We described an unusual combination of fibroblastic connective nevus (FCTN) already present at birth with underlying vascular anomalies. Overall, the lesion appeared as a large purplish-brown mass in the groin region up to the third of the right thigh, with partial spontaneous regression during the first three months of life. The FCTN observed exhibited several unusual characteristics: it was congenital, large in size, and located in the lower limbs. Finally, it represented the first case described in which an FCTN arose in association with vascular anomalies.


Subject(s)
Nevus , Skin Neoplasms , Humans , Skin Neoplasms/pathology , Nevus/pathology , Vascular Malformations/pathology , Male , Female , Infant, Newborn , Infant
2.
Proc Natl Acad Sci U S A ; 115(4): E762-E771, 2018 01 23.
Article in English | MEDLINE | ID: mdl-29311338

ABSTRACT

Increasing evidence suggests that early neurodevelopmental defects in Huntington's disease (HD) patients could contribute to the later adult neurodegenerative phenotype. Here, by using HD-derived induced pluripotent stem cell lines, we report that early telencephalic induction and late neural identity are affected in cortical and striatal populations. We show that a large CAG expansion causes complete failure of the neuro-ectodermal acquisition, while cells carrying shorter CAGs repeats show gross abnormalities in neural rosette formation as well as disrupted cytoarchitecture in cortical organoids. Gene-expression analysis showed that control organoid overlapped with mature human fetal cortical areas, while HD organoids correlated with the immature ventricular zone/subventricular zone. We also report that defects in neuroectoderm and rosette formation could be rescued by molecular and pharmacological approaches leading to a recovery of striatal identity. These results show that mutant huntingtin precludes normal neuronal fate acquisition and highlights a possible connection between mutant huntingtin and abnormal neural development in HD.


Subject(s)
Huntington Disease/physiopathology , Neurogenesis , Cell Line , Cell Polarity , Humans , Huntington Disease/genetics , Induced Pluripotent Stem Cells , Telencephalon/cytology
3.
Cell Death Differ ; 22(4): 690-702, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25301063

ABSTRACT

In the adult brain, neurons require local cholesterol production, which is supplied by astrocytes through apoE-containing lipoproteins. In Huntington's disease (HD), such cholesterol biosynthesis in the brain is severely reduced. Here we show that this defect, occurring in astrocytes, is detrimental for HD neurons. Astrocytes bearing the huntingtin protein containing increasing CAG repeats secreted less apoE-lipoprotein-bound cholesterol in the medium. Conditioned media from HD astrocytes and lipoprotein-depleted conditioned media from wild-type (wt) astrocytes were equally detrimental in a neurite outgrowth assay and did not support synaptic activity in HD neurons, compared with conditions of cholesterol supplementation or conditioned media from wt astrocytes. Molecular perturbation of cholesterol biosynthesis and efflux in astrocytes caused similarly altered astrocyte-neuron cross talk, whereas enhancement of glial SREBP2 and ABCA1 function reversed the aspects of neuronal dysfunction in HD. These findings indicate that astrocyte-mediated cholesterol homeostasis could be a potential therapeutic target to ameliorate neuronal dysfunction in HD.


Subject(s)
Cholesterol/biosynthesis , Huntington Disease/physiopathology , Neurons/metabolism , ATP Binding Cassette Transporter 1/genetics , ATP Binding Cassette Transporter 1/metabolism , Animals , Apolipoproteins E/analysis , Apolipoproteins E/metabolism , Astrocytes/cytology , Astrocytes/drug effects , Astrocytes/metabolism , Cell Differentiation/drug effects , Cells, Cultured , Cholesterol/analysis , Cholesterol/metabolism , Cholesterol/pharmacology , Culture Media, Conditioned/pharmacology , Enzyme-Linked Immunosorbent Assay , Humans , Huntingtin Protein , Lipoproteins/metabolism , Mice , Mice, Transgenic , Mutation , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Neural Stem Cells/cytology , Neural Stem Cells/metabolism , Neurons/cytology , Neurons/drug effects , Sterol Regulatory Element Binding Protein 2/genetics , Sterol Regulatory Element Binding Protein 2/metabolism , Trinucleotide Repeats/genetics
4.
Gene Ther ; 20(6): 678-85, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23151521

ABSTRACT

Current therapeutic strategies for Huntington's disease (HD) are focused on symptom management of disease progression. Transcriptional dysregulation is one of the major characteristics in HD. REST is a transcriptional repressor that silences gene expression through binding to RE1/NRSE sites found in the regulatory regions of numerous neuronal genes. Dysregulation of REST and its targeted genes has been reported in different cell and mouse HD models, as well as in biopsies from human patients. In this work, we characterized transcriptional dysregulation associated with REST in two different HD mouse models and assessed the therapeutic effect of interfering with REST function by overexpressing a dominant-negative form (DN:REST). We show that delivery of DN:REST in the motor cortex restores brain-derived neurotrophic factor (BDNF) mRNA and protein levels by reducing endogenous REST occupancy at the Bdnf locus. Similarly, expression of other REST-regulated genes such as Synapsin I (Syn1), Proenkephalin (Penk1) and Cholinergic receptor muscarinic 4 (Chrm4) were restored to normal levels while non-REST-regulated genes were unaffected. This is the first study conducted to investigate REST's role in vivo in a neurodegenerative disease. Our data show that DN:REST in motor cortex reversed RESTs repressive effects on target genes. However, the lack of therapeutic effect on motor function suggests that a more widespread rescue of REST-regulated sites in the affected brain regions may be necessary.


Subject(s)
Brain-Derived Neurotrophic Factor/genetics , Genetic Therapy , Huntington Disease/genetics , Repressor Proteins/genetics , Animals , Brain-Derived Neurotrophic Factor/metabolism , Disease Models, Animal , Gene Expression Regulation/genetics , Gene Transfer Techniques , Humans , Huntington Disease/pathology , Huntington Disease/therapy , Mice , Motor Cortex/metabolism , Neurons/metabolism , Neurons/pathology , Repressor Proteins/therapeutic use
5.
Neurosci Lett ; 494(3): 245-9, 2011 May 02.
Article in English | MEDLINE | ID: mdl-21406216

ABSTRACT

We previously reported impaired cholesterol biosynthesis in rodent Huntington Disease (HD) models and HD patients' fibroblasts and post mortem brains. We also found that plasma levels of 24S-hydroxycholesterol (24OHC), the brain specific elimination product of cholesterol considered a marker of brain cholesterol turnover, were significantly reduced in HD patients at any disease stage. In the present study we analysed by mass spectrometry the fasting plasma levels of cholesterol, its biosynthetic precursors lanosterol and lathosterol, of the whole-body elimination products 27-hydroxycholesterol and of brain 24OHC in a cohort of premanifest and HD patients at different disease stages. We found that the cholesterol precursors lanosterol and lathosterol (both index of whole body cholesterol synthesis), the levels of the bile acid precursor 27-hydroxycholesterol, and of the brain specific 24OHC, were all significantly reduced in manifest HD patients, suggesting that whole-body and brain cholesterol homeostasis are both impaired in HD.


Subject(s)
Brain/metabolism , Cholesterol/metabolism , Huntington Disease/metabolism , Adult , Female , Humans , Male , Middle Aged
6.
Neuroscience ; 168(1): 314-22, 2010 Jun 16.
Article in English | MEDLINE | ID: mdl-20226234

ABSTRACT

Shc(s) family of adaptor molecules has been implicated in several physiological functions. In particular, our previous studies have shown major roles in the mechanisms that control the transition from proliferating neural stem cells (NSCs) to postmitotic neurons in the mammalian brain. In the adult brain, ShcA expression is mainly restricted to a subpopulation of cells in the subventricular zone (SVZ) neurogenic area, enlightening a potential role for this molecule in the establishment/maintenance of this adult NSC niche. In order to investigate this matter, here we took advantage of Cre/lox technology with the purpose of interfering with (or delete) ShcA function in nestin-expressing neural progenitors in vivo. Our analyses revealed signs of anatomical disorganization in the adult brain at the boundary between the striatum and the corpus callosum and reduced thickness both at the ventricular level and through the rostral migratory stream. Analysis of cell proliferation and cell death unveiled a prominent reduction of the former and no substantial alterations of the latter. Ultrastructural studies showed SVZ anatomical disarray and manifest variation in the SVZ cell type composition. In conclusion, these results provide evidence for a role of ShcA in the assembly and/or maintenance of the SVZ NSC niche in the adult brain.


Subject(s)
Lateral Ventricles/anatomy & histology , Shc Signaling Adaptor Proteins/physiology , Stem Cells/cytology , Animals , Axons/ultrastructure , Cell Proliferation , Corpus Callosum/cytology , Corpus Callosum/ultrastructure , Intermediate Filament Proteins/genetics , Lateral Ventricles/cytology , Lateral Ventricles/ultrastructure , Mice , Mice, Inbred C57BL , Mice, Knockout , Nerve Tissue Proteins/genetics , Nestin , Neurogenesis , Organ Size , Prosencephalon/cytology , Prosencephalon/ultrastructure , Shc Signaling Adaptor Proteins/genetics , Src Homology 2 Domain-Containing, Transforming Protein 1 , Stem Cells/metabolism
7.
Neurobiol Dis ; 34(2): 320-31, 2009 May.
Article in English | MEDLINE | ID: mdl-19236914

ABSTRACT

NS cells are a homogeneous population of neural stem cells which were previously derived from embryonic stem cells as well as from the fetal and adult brain. Our previous reports have described a 21 day long neuronal differentiation protocol able to reproducibly convert adult SVZ-derived NS (aNS) cells into a population composed of 65% mature neurons and 35% glial cells. Here we have developed a different procedure specifically applicable to ES-derived NS cells in order to fully explore their neurogenic capacity. Differently from the aNS differentiation procedure, optimized neuronal output from ES-derived NS cells requires replating of the cells on appropriate substrates followed by sequential exposure to modified media. In these conditions, ES-derived NS cells differentiate into neurons with a barely appreciable quota of astrocytes and occasional oligodendrocytes. In particular, 21 days after the beginning of the treatment, 85% of the cells has differentiated into molecularly and electrophysiologically mature neurons belonging to the GABAergic lineage. The procedure, which is applicable with no considerable differences to different ES-derived NS cell lines and to NS cells at different passages, opens to the possibility of molecular and biochemical studies on close-to-uniform stem cell derived neurons.


Subject(s)
Cell Differentiation/physiology , Cell Lineage/physiology , Embryonic Stem Cells/physiology , Neurogenesis/physiology , Neurons/physiology , Action Potentials/drug effects , Action Potentials/physiology , Animals , Astrocytes/cytology , Astrocytes/drug effects , Astrocytes/physiology , Biomarkers/analysis , Biomarkers/metabolism , Cell Culture Techniques , Cell Differentiation/drug effects , Cell Line , Cell Lineage/drug effects , Embryonic Stem Cells/cytology , Embryonic Stem Cells/drug effects , Interneurons/cytology , Interneurons/drug effects , Interneurons/physiology , Mice , Nerve Growth Factors/pharmacology , Nerve Tissue Proteins/analysis , Nerve Tissue Proteins/metabolism , Neurogenesis/drug effects , Neurons/cytology , Oligodendroglia/cytology , Oligodendroglia/drug effects , Oligodendroglia/physiology , Sodium Channels/drug effects , Sodium Channels/physiology , Stem Cell Transplantation/methods , gamma-Aminobutyric Acid/metabolism
8.
Lipids ; 44(4): 337-44, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19130111

ABSTRACT

Mammals express four isoforms of glycerol-3-phosphate acyltransferase (GPAT). The mitochondrial isoform GPAT1 may have been the acyltransferase that appeared first in evolution. The hepatopancreas of the crustacean Macrobrachium borellii has a high capacity for triacylglycerol (TAG) biosynthesis and storage. In order to understand the mechanism of glycerolipid biosynthesis in M. borellii, we investigated its hepatopancreas GPAT activity. In hepatopancreas mitochondria, we identified a GPAT activity with characteristics similar to those of mammalian GPAT1. The activity was resistant to inactivation by SH-reactive N-ethylmaleimide, it was activated by polymyxin-B, and its preferred substrate was palmitoyl-CoA. The reaction products were similar to those of mammalian GPAT1. A 70-kDa protein band immunoreacted with an anti-rat liver GPAT1 antibody. Surprisingly, we did not detect high GPAT specific activity in hepatopancreas microsomes. GPAT activity in microsomes was consistent with mitochondrial contamination, and its properties were similar to those of the mitochondrial activity. In microsomes, TAG synthesis was not dependent on the presence of glycerol-3 phosphate as a substrate, and the addition of monoacylglycerol as a substrate increased TAG synthesis 2-fold. We conclude that in M. borellii the de novo triacylglycerol biosynthetic pathway can be completed in the mitochondria. In contrast, TAG synthesis in the ER may function via the monoacylglycerol pathway.


Subject(s)
Glycerol-3-Phosphate O-Acyltransferase/metabolism , Hepatopancreas/enzymology , Mitochondria, Liver/enzymology , Triglycerides/biosynthesis , Animals , Electrophoresis, Polyacrylamide Gel , Esterification , Microsomes, Liver/metabolism , Palaemonidae
9.
Urologia ; 76(1): 53-5, 2009.
Article in English | MEDLINE | ID: mdl-21086331

ABSTRACT

Primary and secondary artery-ureteral fistulas are a rare condition. In this case report we describe a case of misunderstood iliac artery-ureteral fistula, with negative radiological preoperative imaging, which occurred in a man as late complication of ureterocutaneostomy.

10.
Cell Death Differ ; 15(12): 1847-56, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19011641

ABSTRACT

Although new culture conditions enable homogeneous and long-term propagation of radial glia-like neural stem (NS) cells in monolayer and serum-free conditions, the efficiency of the conversion of NS cells into terminally differentiated, functionally mature neurons is relatively limited and poorly characterized. We demonstrate that NS cells derived from adult mouse subventricular zone robustly develop properties of mature neurons when exposed to an optimized neuronal differentiation protocol. A high degree of cell viability was preserved. At 22 days in vitro, most cells (65%) were microtubule-associated protein 2(+) and coexpressed gamma-aminobutyric acid (GABA), GAD67, calbindin and parvalbumin. Nearly all neurons exhibited sodium, potassium and calcium currents, and 70% of them fired action potentials. These neurons expressed functional GABA(A) receptors, whereas activable kainate, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid and N-methyl-D-aspartic acid receptors were present in approximately 80, 30 and 2% of cells, respectively. Antigenic and functional properties were efficiently and reliably reproduced across experiments and cell passages (up to 68). This is the first report showing a consistent and reproducible generation of large amounts of neurons from long-term passaged adult neural stem cells. Remarkably, the neuronal progeny carries a defined set of antigenic, biochemical and functional characteristics that make this system suitable for studies of NS cell biology as well as for genetic and chemical screenings.


Subject(s)
Cell Division , Cerebral Ventricles/cytology , Neurons/cytology , Stem Cells/cytology , Action Potentials , Animals , Astrocytes/cytology , Cell Differentiation , Cell Line , Cell Proliferation , Cell Shape , Ion Channel Gating , Mice , Neurons/metabolism , Potassium Channels/metabolism , Receptors, GABA/metabolism , Receptors, Glutamate/metabolism , Reproducibility of Results , Sodium Channels/metabolism , Stem Cells/metabolism , Time Factors , gamma-Aminobutyric Acid/metabolism
11.
AIDS Care ; 20(4): 495-502, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18449829

ABSTRACT

In the last few years, highly active antiretroviral therapy (HAART) has resulted in a remarkable decrease in HIV-related morbidity and mortality. This "new deal" encouraged clinical research in investigating patients' manifest behaviours and their beliefs regarding their health status, which likely influence not only their treatment-linked behaviours but also their quality of life. Locus of control has been shown to be a construct that can predict and explain health-related behaviours. The Multidimensional Health Locus of Control Form C (MHLC-C) is a condition-specific locus of control scale that can be easily adapted for use with any medical or health-related condition. With the aim to enhance the knowledge about the HIV+ patients' point of view of their complex health condition, this study preliminarily investigated the psychometrics properties of the MHLC-C Italian version and its generalizability across samples defined both by being adherent or not and by gender. Two more samples of chronic patients (Cardiac Surgery and Cancer) were enrolled to better characterize the HIV+ patient's MHLC-C profile. The results showed the validity, reliability and generalizability of the 4-factor structure of MHLC-C. More interestingly, HIV+ subjects revealed a peculiar pattern of beliefs regarding their health condition that clinicians should take into account when managing patients' complex bio-psychosocial condition.


Subject(s)
Antiretroviral Therapy, Highly Active , HIV Infections/psychology , Health Status , Internal-External Control , Patient Compliance/psychology , Adolescent , Adult , Chronic Disease , Factor Analysis, Statistical , Female , HIV Infections/drug therapy , Humans , Male , Middle Aged , Surveys and Questionnaires
12.
AIDS Care ; 20(5): 571-5, 2008 May.
Article in English | MEDLINE | ID: mdl-18484327

ABSTRACT

Recent literature has shown that adherence to HAART is a multi-faceted phenomenon, which involves both behavioural and psychological features. Therefore, the results obtained so far, though promising, have not yet unambiguously identified the factors that could predict non-adherence. Since any support for strengthening the adherence should take into account the HIV+ patients' perception of both their state of health and their relational style, this study tried to identify some psychological characteristics involved in the adherence phenomenon. A self-administered battery of tests including the Attachment Style Questionnaire (ASQ) and the Multidimensional Health Locus of Control Form-C (MHLC-C) was administered to an Italian sample. Results showed significant gender differences between non-adherent and adherent subjects. Specifically, the psychological profile of non-adherent males seemed focused less on relational aspects and perceived relevance of physicians and of 'significant other people', whilst that of non-adherent females seemed more 'relationship-oriented'. This study means to encourage clinicians to plan specific, gender-focused support for enhancing adherence.


Subject(s)
Antiretroviral Therapy, Highly Active , HIV Infections/psychology , Patient Compliance/psychology , Adolescent , Adult , Emotions/physiology , Female , HIV Infections/drug therapy , Humans , Italy , Male , Middle Aged , Pilot Projects , Sex Factors , Surveys and Questionnaires
13.
Neuroscience ; 152(3): 734-40, 2008 Mar 27.
Article in English | MEDLINE | ID: mdl-18313855

ABSTRACT

An involvement of one particular neurotrophin, namely, the brain-derived neurotrophic factor (BDNF), has been demonstrated in the pathophysiology Huntington's disease. Type-1 cannabinoid (CB1) receptor has been postulated to upregulate BDNF gene transcription. To better understand the relationship between CB1 and BDNF levels in a situation where the striatum is degenerating, we studied, by dual label immunofluorescence, the distribution of CB1 and BDNF in cortical neurons projecting to the striatum in our rat quinolinic acid model of striatal excitotoxicity. We completed our study with quantitative analyses of BDNF protein levels and CB1 binding activity in the cortex. We show that, 2 weeks post lesion, cortical neurons contain more BDNF compared with controls and to earlier time points. Such BDNF up-regulation coincides with a higher binding activity and an increased protein expression of CB1. We suggest that after excitotoxic lesions, CB1 might, at least transiently, upregulate BDNF in the attempt to rescue striatal neurons from degeneration.


Subject(s)
Brain-Derived Neurotrophic Factor/metabolism , Cerebral Cortex/metabolism , Corpus Striatum/metabolism , Receptor, Cannabinoid, CB1/metabolism , Animals , Cell Communication/physiology , Cell Survival/physiology , Cerebral Cortex/physiopathology , Corpus Striatum/drug effects , Corpus Striatum/physiopathology , Cytoprotection/physiology , Disease Models, Animal , Fluorescent Antibody Technique , Huntington Disease/metabolism , Huntington Disease/physiopathology , Male , Nerve Degeneration/chemically induced , Nerve Degeneration/metabolism , Nerve Degeneration/physiopathology , Neurotoxins , Protein Binding , Quinolinic Acid , Rats , Rats, Wistar , Time Factors , Up-Regulation/physiology
14.
Urologia ; 75(1): 57-61, 2008.
Article in Italian | MEDLINE | ID: mdl-21086378

ABSTRACT

Neuroendocrine bladder cancer is extremely rare, with an estimated incidence of 0.5%- 0.7%. In bladder cancers there is no evident connection between the neuroendocrine phenotypic expression and the clinical history. However, prognosis is usually poor and the survival rate at 5 years does not exceed 8%, if untreated. METHODS. We are here describing three case reports of bladder carcinoma with neuroendocrine differentiation, which is extremely aggressive and leads rapidly to death. At the present time, the local control of these tumors is achieved by radical cystectomy and radiotherapy; they can be both associated to chemotherapy. However, since these lesions are fairly rare, there is no gold standard therapy and there are no prospective studies on the management of these tumors. CONCLUSIONS. Considering the quick evolution and progression of any variant of the neuroendocrine tumors of the bladder, urologists and anesthetists should see them as real oncological emergencies. A prompt intervention through radical surgery with cystectomy and linfadenectomia, and the anathomo-pathologist's systematic investigation of the scraps could make the approach therapeutic and not only palliative. Prospective studies on neo-adjuvant chemotherapy as well as experimental studies about target therapies may yield new guidelines on the tumor management.

15.
Neuroscience ; 149(1): 38-52, 2007 Oct 12.
Article in English | MEDLINE | ID: mdl-17870247

ABSTRACT

A population of mouse embryonic stem (ES)-derived neural stem cells (named NS cells) that exhibits traits reminiscent of radial glia-like cell population and that can be homogeneously expanded in monolayer while remaining stable and highly neurogenic over multiple passages has been recently discovered. This novel population has provided a unique in vitro system in which to investigate physiological events occurring as stem cells lose multipotency and terminally differentiate. Here we analysed the timing, quality and quantity of the appearance of the excitability properties of differentiating NS cells which have been long-term expanded in vitro. To this end, we studied the biophysical properties of voltage-dependent Na(+) currents as an electrophysiological readout for neuronal maturation stages of differentiating NS cells toward the generation of fully functional neurons, since the expression of neuronal voltage-gated Na(+) channels is an essential hallmark of neuronal differentiation and crucial for signal transmission in the nervous system. Using the whole cell and single-channel cell-attached variations of the patch-clamp technique we found that the Na(+) currents in NS cells showed substantial electrophysiological changes during in vitro neuronal differentiation, consisting mainly in an increase of Na(+) current density and in a shift of the steady-state activation and inactivation curves toward more negative and more positive potentials respectively. The changes in the Na(+) channel system were closely related with the ability of differentiating NS cells to generate action potentials, and could therefore be exploited as an appropriate electrophysiological marker of ES-derived NS cells undergoing functional neuronal maturation.


Subject(s)
Action Potentials/physiology , Cell Differentiation/physiology , Ion Channel Gating/physiology , Neurons/physiology , Potassium Channels, Voltage-Gated/metabolism , Stem Cells/physiology , Action Potentials/drug effects , Action Potentials/radiation effects , Animals , Cell Differentiation/drug effects , Cells, Cultured , Dose-Response Relationship, Radiation , Electric Stimulation/methods , Embryo, Mammalian , Hippocampus/cytology , Ion Channel Gating/drug effects , Ion Channel Gating/radiation effects , Patch-Clamp Techniques/methods , Potassium Channels, Voltage-Gated/genetics , Rats , Sodium Channel Blockers/pharmacology , Stem Cells/drug effects , Tetrodotoxin/pharmacology , Time Factors
16.
Neurobiol Dis ; 27(1): 36-43, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17512749

ABSTRACT

Huntington's disease is one of a group of hereditary neurodegenerative diseases characterized by a glutamine expansion (polyQ) in proteins which are expressed in various cell populations. In agreement with this widespread distribution, we have previously shown that A(2A) receptor signaling is affected in mouse brain as well as in peripheral blood cells from a small cohort of HD patients. Here we analyzed a total of 252 subjects, including 126 HD gene-positive individuals, from different clinical sites. Consistent with our previous data we show that A(2A) receptor B(max) values are robustly increased at all HD stages as well as in 32 pre-symptomatic subjects. We report that the same abnormality is present also in other polyQ but not in non-polyQ inherited neurological disorders. Finally, we demonstrate that the same peripheral cells exhibit an altered membrane fluidity, a finding that may explain the observed change in receptor density. We argue that the observed alteration in lymphocytes reflects the presence of the mutant protein, and we suggest that the measure of the A(2A) receptor binding activity might be of potential interest for a peripheral assessment of chemicals capable of interfering with the immediate toxic effects of the mutation.


Subject(s)
Friedreich Ataxia/genetics , Huntington Disease/genetics , Peptides/genetics , Receptors, Adrenergic, alpha-2/genetics , Receptors, Adrenergic, alpha-2/metabolism , Spinocerebellar Ataxias/genetics , Adolescent , Adult , Age of Onset , Aged , Biomarkers/metabolism , Cell Polarity/physiology , Female , Friedreich Ataxia/metabolism , Humans , Huntington Disease/drug therapy , Huntington Disease/metabolism , Lymphocytes/metabolism , Male , Membrane Fluidity/physiology , Middle Aged , Peptides/metabolism , Spinocerebellar Ataxias/metabolism , Trinucleotide Repeats
17.
Neuroscience ; 133(1): 105-15, 2005.
Article in English | MEDLINE | ID: mdl-15893635

ABSTRACT

Shc family of adaptor molecules has been demonstrated to play an important role during the transition from proliferating neural stem cells to postmitotic neurons. Previous studies from our group demonstrated a progressive decrease of ShcA levels occurring in coincidence with the end of embryonic neurogenesis and neuronal maturation, being ShcB and ShcC the major Shc molecules expressed in the mature brain. A growing body of evidence indicates that ShcB and ShcC are neuronal specific molecules exerting important roles in neuronal survival and phenotypic stability thus becoming potential attracting target molecules for development of drugs for interfering with brain demises. Here, we examine the expression pattern of ShcB and ShcC in neuronal populations composing the adult central and peripheral nervous system, in order to better elucidate their roles in vivo. We found a heterogeneous and peculiar presence and subcellular localization of ShcB and ShcC in specific neuronal populations, enlightening a potential specific requirement of these two molecules in the survival/maintenance of defined neuronal subtypes.


Subject(s)
Brain Chemistry/genetics , Brain Chemistry/physiology , Gene Expression Profiling , Gene Expression Regulation/physiology , Neurons/metabolism , Neuropeptides/biosynthesis , Neuropeptides/genetics , Animals , Basal Ganglia/cytology , Basal Ganglia/metabolism , Blotting, Western , Cerebellum/cytology , Cerebellum/metabolism , Eye/metabolism , Ganglia, Spinal/cytology , Ganglia, Spinal/metabolism , Immunohistochemistry , In Situ Hybridization , Neurons/ultrastructure , Olfactory Mucosa/cytology , Olfactory Mucosa/metabolism , Optic Nerve/cytology , Optic Nerve/metabolism , Peripheral Nerves/metabolism , Rats , Rats, Wistar , Shc Signaling Adaptor Proteins , Spinal Cord/cytology , Spinal Cord/metabolism , Src Homology 2 Domain-Containing, Transforming Protein 3 , Subcellular Fractions/metabolism , Subcellular Fractions/ultrastructure , src Homology Domains
18.
Cell Death Differ ; 11(11): 1179-91, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15257302

ABSTRACT

Deficiency of the apoptosome component Apaf1 leads to accumulation of supernumerary brain cells in mouse embryos. We observed that neural precursor cells (NPCs) in Apaf1(-/-) embryos escape programmed cell death, proliferate and retain their potential to differentiate. To evaluate the circumstances of Apaf1(-/-) NPC survival and investigate their fate under neurodegenerative conditions, we established cell lines of embryonic origin (ETNA). We found that Apaf1(-/-) NPCs resist common apoptotic stimuli and neurodegenerative inducers such as amyloid-beta peptide (typical of Alzheimer's disease) and mutant G93A superoxide dismutase 1 (typical of familial amyotrophic lateral sclerosis). Similar results were obtained in Apaf1(-/-) primary cells. When death is prevented by Apaf1 deficiency, cytochrome c is released from mitochondria and rapidly degraded by the proteasome, but mitochondria remain intact. Under these conditions, neither activation by cleavage of initiator caspases nor release of alternative apoptotic inducers from mitochondria takes place. In addition, NPCs can still differentiate, as revealed by neurite outgrowth and expression of differentiation markers. Our findings imply that the mitochondrion/apoptosome pathway is the main route of proneural and neural cells to death and that its inhibition prevents them from dismantling in neurodegenerative conditions. Indeed, the ETNA cell model is ideally suited for exploring the potential of novel cell therapies for the treatment of human neurodegenerations.


Subject(s)
Apoptosis , Nerve Degeneration , Neurons/pathology , Proteins/physiology , Amyloid beta-Peptides/chemistry , Animals , Apoptotic Protease-Activating Factor 1 , Blotting, Western , Bromodeoxyuridine/pharmacology , Caspases/metabolism , Cell Death , Cell Differentiation , Cell Proliferation , Cell Survival , Immunohistochemistry , Immunoprecipitation , Membrane Potentials , Mice , Mice, Transgenic , Microscopy, Fluorescence , Mitochondria/metabolism , Mitochondria/pathology , Neurodegenerative Diseases , Peptide Fragments/chemistry , Plasmids/metabolism , Time Factors , Transgenes
19.
J Thorac Cardiovasc Surg ; 128(1): 117-23, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15224030

ABSTRACT

BACKGROUND: The efficacy of the St Jude Medical Symmetry aortic connector (St Jude Medical, Inc, St Paul, Minn) for coronary artery bypass is currently debated. Potential drawbacks are the biocompatibility of the endoluminal device, the need for graft manipulation during the procedure, and the 90 degrees offset of the vein graft from the ascending aorta, which may induce graft kinking and abnormal fluid dynamics. In this article, a computational approach was designed to investigate the fluid dynamics pattern at the proximal graft. METHODS: Four models of hand-sewn anastomoses and two models of automated anastomoses were constructed; a finite volume technique was used to simulate realistic graft fluid dynamics, including aortic compliance and proper aortic and graft flow rates. The anastomosis geometry performance was analyzed by calculating time-averaged wall shear stress and the oscillating shear index at the toe and heel regions of the proximal graft. RESULTS: Time-averaged wall shear stress was significantly lower in the hand-sewn anastomosis models than in the two models that simulated the use of the aortic connector (0.38 +/- 0.07 Pa vs 1.32 +/- 0.4 Pa). Higher oscillating shear index values were calculated in the hand-sewn anastomosis models (0.15 +/- 0.02 Pa vs 0.06 +/- 0.02 Pa). CONCLUSIONS: Automated anastomosis geometry is associated with less critical fluid dynamics than with conventional hand-sewn anastomosis: the shape of the proximal graft induces more physiological wall shear stresses and less oscillating flow, suggesting a lower risk of atherosclerotic plaque and intimal hyperplasia as compared with conventional anastomosis geometry. Therefore, the reported early thrombosis and late failure of the St Jude Medical aortic connector anastomoses are not related to unfavorable fluid dynamics.


Subject(s)
Aorta/physiopathology , Aorta/surgery , Aortic Valve , Heart Valve Prosthesis Implantation , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Thrombosis/epidemiology , Thrombosis/etiology , Veins/physiopathology , Veins/surgery , Acute Disease , Anastomosis, Surgical , Blood Flow Velocity/physiology , Computer Simulation , Equipment Design , Graft Occlusion, Vascular/epidemiology , Graft Occlusion, Vascular/etiology , Graft Occlusion, Vascular/physiopathology , Humans , Models, Cardiovascular , Postoperative Complications/physiopathology , Risk Factors , Systole/physiology , Thrombosis/physiopathology , Vascular Patency/physiology
20.
Neuromuscul Disord ; 13(10): 813-21, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14678804

ABSTRACT

A previous study in proximal myotonic myopathy (PROMM/DM-2) and myotonic dystrophy type 1 (DM-1) using brain positron emission tomography demonstrated a reduced cerebral blood flow in the frontal and temporal regions associated with cognitive impairment. The objective was to investigate further cognitive and behavioural aspects in a new series of patients with DM-1 and PROMM/DM-2. Nineteen patients with genetically determined PROMM/DM-2 and 21 patients with moderately severe DM-1 underwent neuropsychological testing and neuropsychiatric interviews. DM-1 and PROMM/DM-2 patients had significantly lower scores on tests of frontal lobe function compared to controls. Neuropsychiatric interviews demonstrated an avoidant trait personality disorder in both patient groups. Brain single photon emission computed tomography showed frontal and parieto-occipital hypoperfusion. The results suggest that there is a specific cognitive and behavioural profile in PROMM/DM-2 and in DM-1, and that this profile is associated with hypoperfusion in frontal and parieto-occipital regions of the brain.


Subject(s)
Cognition Disorders/etiology , Myotonic Disorders/physiopathology , Myotonic Disorders/psychology , Myotonic Dystrophy/physiopathology , Myotonic Dystrophy/psychology , Personality Disorders/etiology , Adult , Age of Onset , Aged , Cerebrovascular Circulation/physiology , Cognition Disorders/diagnostic imaging , Cognition Disorders/physiopathology , Female , Frontal Lobe/diagnostic imaging , Frontal Lobe/physiopathology , Humans , Male , Middle Aged , Myotonic Disorders/diagnostic imaging , Myotonic Dystrophy/diagnostic imaging , Neuropsychological Tests , Occipital Lobe/diagnostic imaging , Occipital Lobe/physiopathology , Parietal Lobe/diagnostic imaging , Parietal Lobe/physiopathology , Personality Disorders/diagnostic imaging , Personality Disorders/physiopathology , Tomography, Emission-Computed, Single-Photon
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