Search

Huntington disease (HD) is an autosomal dominant disease characterized by motor, behavioral, and cognitive symptoms, caused by the pathological expansion of more than 35 CAG/CAA repeats in the HTT gene. We describe the phenotype of a patient compatible with HD. Several family members were reported as affected, and a paternal cousin and his daughter carried 39 and 42 CAG/CAA. HD genetic testing in proband showed homozygosity for a 14 CAG/CAA allele. Considering the phenotype and family history, HTT gene sequence was performed, revealing heterozygosity for the c.51C>G variant that changes the last nucleotide before the CAG tract, causing misannealing of forward primer (HD344) and dropout of the expanded allele. Polymerase chain reaction (PCR) analysis performed with an alternative forward primer demonstrated a 41 CAG/CAA allele. The c.51C>G variant was not detected in the affected cousin, thus suggesting a de novo occurrence. The lack of biological samples from the proband father and grandmother prevented further investigations to establish in which family member the variant occurred. These data indicate that patients presenting HD phenotype, and homozygous for a normal HTT CAG/CAA allele should be thoroughly evaluated for the presence of a genetic variant, even de novo, within the repeat region that may hamper genetic diagnosis.

The Huntingtin (HTT) gene contains a CAG repeat in exon 1, whose expansion beyond 39 repeats consistently leads to Huntington's disease (HD), whereas normal-to-intermediate alleles seemingly modulate brain structure, function and behavior. The role of the CAG repeat in Autism Spectrum Disorder (ASD) was investigated applying both family-based and case-control association designs, with the SCA3 repeat as a negative control. Significant overtransmission of "long" CAG alleles (≥17 repeats) to autistic children and of "short" alleles (≤16 repeats) to their unaffected siblings (all p < 10-5 ) was observed in 612 ASD families (548 simplex and 64 multiplex). Surprisingly, both 193 population controls and 1,188 neurological non-HD controls have significantly lower frequencies of "short" CAG alleles compared to 185 unaffected siblings and higher rates of "long" alleles compared to 548 ASD patients from the same families (p < .05-.001). The SCA3 CAG repeat displays no association. "Short" HTT alleles seemingly exert a protective effect from clinically overt autism in families carrying a genetic predisposition for ASD, while "long" alleles may enhance autism risk. Differential penetrance of autism-inducing genetic/epigenetic variants may imply atypical developmental trajectories linked to HTT functions, including excitation/inhibition imbalance, cortical neurogenesis and apoptosis, neuronal migration, synapse formation, connectivity and homeostasis.

Here we report on a singleton patient affected by a complicated congenital syndrome characterized by growth delay, retinal dystrophy, sensorineural deafness, myopathy, ataxia, combined pituitary hormone deficiency, associated with mitochondrial impairment. Targeted clinical exome sequencing led to the identification of a homozygous missense variant in OTX2. Since only dominant mutations within OTX2 have been associated with cases of syndromic microphthalmia, retinal dystrophy with or without pituitary dysfunctions, this represents the first report of an OTX2 recessive mutation. Part of the phenotype, including ataxia, myopathy and multiple mitochondrial respiratory chain defects, seemed not related to OTX2. Further analysis of next generation sequencing (NGS) data revealed additional candidate variants: a homozygous variant in LETM1, and heterozygous rare variants in AFG3L2 and POLG. All three genes encode mitochondrial proteins and the last two are known to be associated with ataxia, a neurological sign present also in the father of the proband. With our study, we aim to encourage the integration of NGS data with a detailed analysis of clinical description and family history in order to unravel composite genotypes sometimes associated with complicated phenotypes.

Background Erythropoietin (EPO) derivatives have been found to increase frataxin levels in Friedreich's ataxia (FRDA) in vitro. This multicenter, double-blind, placebo-controlled, phase II clinical trial aimed to evaluate the safety and tolerability of Lu AA24493 (carbamylated EPO; CEPO). Methods Thirty-six ambulatory FRDA patients harboring >400 GAA repeats were 2:1 randomly assigned to either CEPO in a fixed dose (325 µg thrice-weekly) or placebo. Safety and tolerability were assessed up to 103 days after baseline. Secondary outcome measures of efficacy (exploration of biomarkers and ataxia ratings) were performed up to 43 days after baseline. Results All patients received six doses of study medication. Adverse events were equally distributed between CEPO and placebo. There was no evidence for immunogenicity of CEPO after multiple dosing. Biomarkers, such as frataxin, or measures for oxidative stress and ataxia ratings did not differ between CEPO and placebo. Conclusion CEPO was safe and well tolerated in a 2-week treatment phase. Secondary outcome measures remained without apparent difference between CEPO and placebo. © 2014 International Parkinson and Movement Disorder Society

Humans vary substantially in their ability to learn new motor skills. Here, we examined inter-individual differences in learning to play the piano, with the goal of identifying relations to structural properties of white matter fiber tracts relevant to audio-motor learning. Non-musicians (n = 18) learned to perform three short melodies on a piano keyboard in a pure audio-motor training condition (vision of their own fingers was occluded). Initial learning times ranged from 17 to 120 min (mean ± SD: 62 ± 29 min). Diffusion-weighted magnetic resonance imaging was used to derive the fractional anisotropy (FA), an index of white matter microstructural arrangement. A correlation analysis revealed that higher FA values were associated with faster learning of piano melodies. These effects were observed in the bilateral corticospinal tracts, bundles of axons relevant for the execution of voluntary movements, and the right superior longitudinal fasciculus, a tract important for audio-motor transformations. These results suggest that the speed with which novel complex audio-motor skills can be acquired may be determined by variability in structural properties of white matter fiber tracts connecting brain areas functionally relevant for audio-motor learning.

Background: Friedreich ataxia is a rare disease caused by GAA-trinucleotide-repeat expansions in the frataxin gene, leading to marked reduction of qualitatively normal frataxin protein. Recently, human recombinant erythropoietin was reported to increase frataxin levels in patients with Friedreich ataxia. Methods: We performed a 6-month, randomized placebo-controlled, double-blind, dose-response pilot trial to assess the safety and efficacy of erythropoietin in increasing frataxin levels. Sixteen adult patient with Friedreich ataxia were randomly assigned to erythropoietin (n = 11) or matching placebo (n = 5). All patients continued Idebenone treatment (5 mg/kg/day). Treatment consisted of a 6-month scaling-up phase, in which erythropoietin was administered intravenously at the following doses: 20,000 IU every 3 weeks, 40,000 IU every 3 weeks, and 40,000 IU every 2 weeks. Results: Erythropoietin treatment was safe and well tolerated, but did not result in any significant hematological, clinical, or biochemical effects in Friedreich ataxia patients. © 2012 Movement Disorder Society

Summary Given the key role played by honey bees in almost all terrestrial ecosystems, maintaining bee populations in adequate sanitary conditions is crucial for these essential pollinators to continue their work. From the beginning of the 21st century, beekeepers have reported a progressive increase in the overwintering mortality of honey bee colonies worldwide. Despite the failure to reach a consensus regarding the cause of this phenomenon, pathogens are thought to be strongly implicated. In the present work, we provide evidence of the negative effects of colony parasitization by Nosema spp. – primarily by N. ceranae– on the effectiveness of acaricide strips to treat Varroa destructor. The effectiveness of the Varroa mite strip treatment (Apivar®) was greater in colonies in which Nosema spp. parasitization had been controlled. Several studies report that infection by Nosema spp. may affect the behaviour of worker bees. As the effectiveness of Varroa strip treatment depends on bees contacting the strips and their subsequent interaction within the colony, such behavioural and social alterations could interfere with the treatment and allow more severe effects to develop in the colonies infected by Nosema. These results should be considered when assessing acaricide treatments in field conditions due to the high prevalence of both pathogens worldwide.

Summary Microsporidiosis of adult honeybees caused by Nosema apis and Nosema ceranae is a common worldwide disease with negative impacts on colony strength and productivity. Few options are available to control the disease at present. The role of the queen in bee population renewal and the replacement of bee losses due to Nosema infection is vital to maintain colony homeostasis. Younger queens have a greater egg laying potential and they produce a greater proportion of uninfected newly eclosed bees to compensate for adult bee losses; hence, a field study was performed to determine the effect of induced queen replacement on Nosema infection in honey bee colonies, focusing on colony strength and honey production. In addition, the impact of long-term Nosema infection of a colony on the ovaries and ventriculus of the queen was evaluated. Queen replacement resulted in a remarkable decrease in the rates of Nosema infection, comparable with that induced by fumagillin treatment. However, detrimental effects on the overall colony state were observed due to the combined effects of stressors such as the queenless condition, lack of brood and high infection rates. The ovaries and ventriculi of queens in infected colonies revealed no signs of Nosema infection and there were no lesions in ovarioles or epithelial ventricular cells.

Eur J Clin Invest 2011; 41 (12): 1318–1322 Abstract Background Production of reactive oxygen species after ischaemic stroke may enhance tissue damage through multiple molecular pathways. Materials and methods In this study, we examined the serum levels of lipoperoxide and hydroperoxide, conjugated dienes and total antioxidant capacity levels in 50 patients with acute ischaemic stroke (T0) to evaluate the possibility to use them as specific biochemical markers for cerebral ischaemia. Determinations were repeated after a month (T1) to correlate their relative changes with clinical evolution. Results Lipoperoxide, hydroperoxide and conjugated diene levels in platelets were significantly higher in the early stages with respect to their late evaluation. On the contrary, total antioxidant capacity showed a significant increase at T1 with respect to T0. A significant negative correlation between total antioxidant capacity and NIHSS score at T0 and T1 was found. There was a significant positive correlation between lipoperoxide, hydroperoxide and conjugated dienes levels and NIHSS score at T0 and at T1. Conclusions These findings suggest that changes in free radical generation and consequent oxidative stress may have a role in the pathogenesis of acute ischaemic lesions. The activation of defence mechanisms like total antioxidant capacity could be involved in the limitation of ischaemic damage progression.

Five out of nine consecutive patients with HIV-related visceral aspergillosis observed by us since 1984 were diagnosed only at necropsy examination. The histopathological features of these five patients [two with isolated pneumonia, one with central nervous system (CNS) involvement, one with brain abscess and respiratory disease and one with pulmonary, pleural and kidney infection] have been evaluated according to epidemiological, clinical and radiological features. On the basis of our experience, life-threatening aspergillosis, which is often misdiagnosed or missed in the setting of HIV infection and AIDS, should be suspected in patients with far-advanced underlying disease and unexplained signs and symptoms, even in the absence of some presumed risk factors (i.e. neutropenia and prior steroid treatment). Plain chest radiography and bronchoscopy with broncholaveolar lavage may fail to reveal respiratory disease, CNS aspergillosis is not necessarily associated with suggestive neuroradiological features and disseminated disease may present with multiorgan failure. The unfavorable outcome of this emerging AIDS complication can be improved only by earlier diagnosis based on invasive techniques and appropriate and timely treatment.

Background This study was performed to understand the metabolic effects of raloxifene, a selective oestrogen receptor modulator, on platelets in healthy non-obese postmenopausal women. The data were compared to untreated subjects. Materials and methods Platelet nitric oxide activity (NO) and peroxynitrite level, platelet inducible and endothelial nitric oxide synthase expression and plasma lipids were evaluated at baseline and after 12 months of raloxifene or placebo treatment. Results A significant increase of platelet NO and reduction of platelet peroxynitrite levels, as well as a decrease of inducible nitric oxide synthase expression, was observed 12 months after raloxifene therapy as compared to baseline or placebo treatment. Moreover, raloxifene treatment caused a significant increase in high-density lipoprotein cholesterol and a decrease of total cholesterol and low-density lipoprotein cholesterol were observed versus baseline values (P

Background Homocysteine (Hcy) is an independent risk factor for cardiovascular disease (CVD). Individuals with Type 1 and Type 2 diabetes are more susceptible to the effects of homocysteine than non-diabetic subjects. The interaction between homocysteine-thiolactone (Hcy-thiolactone), a reactive product of Hcy, and low-density lipoproteins (LDL) induces the formation of homocystamide-LDL adducts (Hcy-LDL) and it has been suggested that homocysteinylation could increase atherogenicity of lipoproteins. Aim The aim of the study was to compare the effect of in vitro homocysteinylation of LDL isolated from healthy control subjects (C-LDL) and from Type 1 diabetic patients (DM-LDL) and to investigate the effect of homocysteinylated LDL (Hcy-C-LDL and Hcy-DM-LDL) on peroxynitrite production of endothelial cells. Methods The in vitro homocysteinylation of LDL isolated from control (n = 12) and DM subjects (n = 12) was carried out by incubating lipoproteins with Hcy-thiolactone. The reaction was verified by quanitifying the increase in sulphydryl groups (–SH groups) in Hcy-LDL with respect to control LDL. Control and homocysteinylated LDL were incubated with human aortic endothelial cells (HAEC) in culture. Peroxynitrite production in cells treated in different experimental conditions was assayed by a fluorimetric method. Results The increase in –SH groups after incubation with homocysteine was greater in LDL from diabetic subjects compared with LDL from control subjects (P

Background Anorexia nervosa (AN), a psychosomatic disorder, has serious negative effects on multiple organs and systems of the human body. Anorexia nervosa usually runs a chronic course and is associated with significant morbidity and mortality. In order to elucidate the role played by lipids in AN, in the present study we compared the plasma lipid profile and the chemical-physical properties of lipoproteins obtained from subjects affected by AN. Materials and methods The study was performed on lipoproteins of AN subjects and of age-matched healthy subjects used as controls. We tested the susceptibility to oxidative stress in vitro, the fatty acid content, the fluidity using 2-dimethylamino-(6-lauroyl)-naphthalene (Laurdan) and 1,6-difenil-1,3,5-esatriene (DPH) probes. Results Present results indicate that AN patients present a deep alteration of the composition and of chemical-physical properties in circulating lipoproteins, even in the absence of significant modifications to clinical metabolic parameters. A significantly decreased body mass index (BMI) was found in AN patients in comparison with controls. Anorexia nervosa patients showed a significant modification of phospholipids to protein ratio and a significantly increased percentage of unsaturated fatty acids compared with control subjects as well as a decreased fluidity, a significantly increased percentage of liquid-crystalline phase in VLDL, and a significantly reduced susceptibility to oxidative stress, more pronounced in LDL. Conclusions These results confirm the hypothesis that anorexia is accompanied by changes of lipid metabolism in the central nervous system (CNS).

A recently developed microdilution method (Sensititre) YeastOne) may represent a valid alternative to the National Committee for Clinical Laboratory Standards (NCCLS) method for routine testing. The Medical Mycology Committee of the Associazione Microbiologi Clinici Italiani (AMCLI) decided to evaluate its reproducibility and reliability compared with the NCCLS M27A protocol and the E-test. Nineteen strains each of Candida albicans and Ca. parapsilosis, isolated from systemic infections, were tested against amphotericin B, flucytosine, ketoconazole, itraconazole, and fluconazole. All the participating laboratories tested the YeastOne panels, while the E-test and the NCCLS method were performed by two laboratories each. Interlaboratory reproducibility showed a good correlation (from 95% for amphotericin B to 92.5% for flucytosine). The agreement between NCCLS and YeastOne ranged from 95 (ketoconazole and itraconazole) to 100% (amphotericin B and flucytosine), whereas the agreement between E-test and YeastOne ranged from 72.5 (fluconazole) to 100% (amphotericin B and flucytosine). The Sensititre YeastOne panels appear to be an excellent alternative to both the E-test and the NCCLS protocol for antifungal susceptibility testing.

Background. The physiopathological relevance of plasma lipid concentrations is supported by the observation that they might affect the physicochemical properties of the plasma membrane of circulating cells and might be crucial in the pathological conditions complicating pregnancy. Methods. Plasma and erythrocyte membrane lipid composition, membrane fluidity and function [membrane-bound enzyme sodium/potassium adenosine triphosphatase (Na + /K + -ATPase) activity] were studied in 24 healthy women in the nonpregnant condition and at 12, 24 and 38 weeks' gestation. Results. The plasma showed an increase in total and high density lipoprotein (HDL) cholesterol, triglyceride (TG) and phospholipid (PL) levels. In the erythrocyte membrane we found the cholesterol/phospholipid (C/PL) ratio increased and the saturated to unsaturated fatty acid (FA) ratio (Sat/Unsat) significantly reduced; fluorescence polarization showed an initial increase during pregnancy and a progressive decrease afterwards; Na + /K + -ATPase a...

Homocysteine-thiolactone (HcyT) is a toxic product whose synthesis is directly proportional to plasma homocysteine (Hcy) levels. Previous studies demonstrated that the interaction between HcyT and low density lipoproteins (LDL) induces the formation of homocystamide-LDL adducts (Hcy-LDL). Structural and functional alterations of Hcy-LDL have been described and it has been suggested that homocysteinylation could increase atherogenicity of LDL. Oxidative damage of endothelial cells (EC) is considered to be a critical aspect of the atherosclerotic process. To further investigate the molecular mechanisms involved in the atherogenicity of homocysteinylated LDL, we studied the effect of interaction between Hcy-LDL and EC on cell oxidative damage, using human aortic endothelial cells (HAEC) as experimental model. Homocysteinylation of LDL was carried out by incubation of LDL, isolated from plasma of healthy normolipemic subjects, with HcyT (10–100 μM). In our experimental conditions, homocysteinylation treatment was not accompanied by oxidative damage of LDL. No modifications of apoprotein structure and physico-chemical properties were observed in Hcy-LDL with respect to control LDL (c-LDL), as evaluated using the intrinsic fluorescence of tryptophan and the probe Laurdan incorporated in lipoproteins. Our results demonstrated that Hcy-LDL incubated at 37°C for 3 h with HAEC, induced an oxidative damage on human EC with a significant increase of lipid hydroperoxides in cells incubated with Hcy-LDL with respect to cell incubated with c-LDL. The compositional changes were associated with a significant decrease viability in cells treated with Hcy-LDL. The relationship between the levels of –SH groups of LDL and the oxidative damage of HAEC has been demonstrated. These results suggest that Hcy-LDL exert a cytotoxic effect that is likely related to an increase in lipid peroxidation and oxidative damage of EC. © 2004 Wiley-Liss, Inc.