G. Casari - Academia.edu (original) (raw)

Papers by G. Casari

Brain, 2003

Restless legs syndrome (RLS) is a common neurological disorder characterized by an irresistible d... more Restless legs syndrome (RLS) is a common neurological disorder characterized by an irresistible desire to move the extremities associated with paraesthesia/dysaesthesia. These symptoms occur predominantly at rest and worsen at night, resulting in nocturnal insomnia and chronic sleep deprivation. In this paper, we show sig-ni®cant evidence of linkage to a new locus for RLS on chromosome 14q13-21 region in a 30-member, threegeneration Italian family affected by RLS and periodic leg movements in sleep (PLMS). This is the second RLS locus identi®ed so far and the ®rst consistent with an autosomal dominant inheritance pattern. The new RLS critical region spans 9.1 cM, between markers D14S70 and D14S1068. The maximum two-point log of odds ratio score value, of 3.23 at q = 0.0, was obtained for marker D14S288. The accurate clinical evaluation of RLS-affected, as well as unaffected, family members allowed for the con®guring of RLS as a phenotypic spectrum ranging from PLMS to RLS. Motor component, both while awake and during sleep, was an important aspect of the phenotype in the family analysed. The complementary clinical and genetic studies on multiplex families are likely to be of the utmost importance in unfolding the complete expressivity of RLS phenotype spectrum.

Molecular and Cellular Biology, 2006

The m -AAA protease, an ATP-dependent proteolytic complex in the mitochondrial inner membrane, co... more The m -AAA protease, an ATP-dependent proteolytic complex in the mitochondrial inner membrane, controls protein quality and regulates ribosome assembly, thus exerting essential housekeeping functions within mitochondria. Mutations in the m -AAA protease subunit paraplegin cause axonal degeneration in hereditary spastic paraplegia (HSP), but the basis for the unexpected tissue specificity is not understood. Paraplegin assembles with homologous Afg3l2 subunits into hetero-oligomeric complexes which can substitute for yeast m -AAA proteases, demonstrating functional conservation. The function of a third paralogue, Afg3l1 expressed in mouse, is unknown. Here, we analyze the assembly of paraplegin into m -AAA complexes and monitor consequences of paraplegin deficiency in HSP fibroblasts and in a mouse model for HSP. Our findings reveal variability in the assembly of m -AAA proteases in mitochondria in different tissues. Homo-oligomeric Afg3l1 and Afg3l2 complexes and hetero-oligomeric as...

BMC Medical Genetics, 2008

Background Mutations in the SPG4 gene (spastin) and in the SPG3A gene (atlastin) account for the ... more Background Mutations in the SPG4 gene (spastin) and in the SPG3A gene (atlastin) account for the majority of 'pure' autosomal dominant form of hereditary spastic paraplegia (HSP). Recently, mutations in the REEP1 gene were identified to cause autosomal dominant HSP type SPG31. The purpose of this study was to determine the prevalence of REEP1 mutations in a cohort of 162 unrelated Caucasian index patients with 'pure' HSP and a positive family history (at least two persons per family presented symptoms). Methods 162 patients were screened for mutations by, both, DHPLC and direct sequencing. Results Ten mutations were identified in the REEP1 gene, these included eight novel mutations comprising small insertions/deletions causing frame shifts and subsequently premature stop codons, one nonsense mutation and one splice site mutation as well as two missense mutations. Both missense mutations and the splice site mutation were not identified in 170 control subjects. Conclus...

Nucleic Acids Research, 2005

An increasing number of eukaryotic and prokaryotic genes are being found to have natural antisens... more An increasing number of eukaryotic and prokaryotic genes are being found to have natural antisense transcripts (NATs). There is also growing evidence to suggest that antisense transcription could play a key role in many human diseases. Consequently, there have been several recent attempts to set up computational procedures aimed at identifying novel NATs. Our group has developed the AntiHunter program for the identification of expressed sequence tag (EST) antisense transcripts from BLAST output. In order to perform an analysis, the program requires a genomic sequence plus an associated list of transcript names and coordinates of the genomic region. After masking the repeated regions, the program carries out a BLASTN search of this sequence in the selected EST database, reporting via email the EST entries that reveal an antisense transcript according to the user-supplied list. Here, we present the newly developed version 2.0 of the AntiHunter tool. Several improvements have been added to this version of the program in order to increase its ability to detect a larger number of antisense ESTs. As a result, AntiHunter can now detect, on average, .45% more antisense ESTs with little or no increase in the percentage of the false positives. We also raised the maximum query size to 3 Mb (previously 1 Mb). Moreover, we found that a reasonable trade-off between the program search sensitivity and the maximum allowed size of the input-query sequence could be obtained by querying the database with the MEGABLAST program, rather than by using the BLAST one. We now offer this new opportunity to users, i.e. if choosing the MEGABLAST option, users can input a query sequence up to 30 Mb long, thus considerably improving the possibility to analyze longer query regions.

BMC Bioinformatics

Background: Targeted resequencing has become the most used and cost-effective approach for identi... more Background: Targeted resequencing has become the most used and cost-effective approach for identifying causative mutations of Mendelian diseases both for diagnostics and research purposes. Due to very rapid technological progress, NGS laboratories are expanding their capabilities to address the increasing number of analyses. Several open source tools are available to build a generic variant calling pipeline, but a tool able to simultaneously execute multiple analyses, organize, and categorize the samples is still missing. Results: Here we describe VarGenius, a Linux based command line software able to execute customizable pipelines for the analysis of multiple targeted resequencing data using parallel computing. VarGenius provides a database to store the output of the analysis (calling quality statistics, variant annotations, internal allelic variant frequencies) and sample information (personal data, genotypes, phenotypes). VarGenius can also perform the "joint analysis" of hundreds of samples with a single command, drastically reducing the time for the configuration and execution of the analysis. VarGenius executes the standard pipeline of the Genome Analysis Tool-Kit (GATK) best practices (GBP) for germinal variant calling, annotates the variants using Annovar, and generates a user-friendly output displaying the results through a web page. VarGenius has been tested on a parallel computing cluster with 52 machines with 120GB of RAM each. Under this configuration, a 50 M whole exome sequencing (WES) analysis for a family was executed in about 7 h (trio or quartet); a joint analysis of 30 WES in about 24 h and the parallel analysis of 34 single samples from a 1 M panel in about 2 h. Conclusions: We developed VarGenius, a "master" tool that faces the increasing demand of heterogeneous NGS analyses and allows maximum flexibility for downstream analyses. It paves the way to a different kind of analysis, centered on cohorts rather than on singleton. Patient and variant information are stored into the database and any output file can be accessed programmatically. VarGenius can be used for routine analyses by biomedical researchers with basic Linux skills providing additional flexibility for computational biologists to develop their own algorithms for the comparison and analysis of data.

Frontiers in Neural Circuits, 2014

Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is a partial sleep-related epilepsy w... more Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is a partial sleep-related epilepsy which can be caused by mutant neuronal nicotinic acetylcholine receptors (nAChR). We applied multi-electrode array (MEA) recording methods to study the spontaneous firing activity of neocortical cultures obtained from mice expressing or not (WT) an ADNFLE-linked nAChR subunit (β2-V287L). More than 100,000 up-states were recorded during experiments sampling from several thousand neurons. Data were analyzed by using a fast sliding-window procedure which computes histograms of the up-state durations. Differently from the WT, cultures expressing β2-V287L displayed long (10-32 s) synaptic-induced up-state firing events. The occurrence of such long up-states was prevented by both negative (gabazine, penicillin G) and positive (benzodiazepines) modulators of GABA A receptors. Carbamazepine (CBZ), a drug of choice in ADNFLE patients, also inhibited the long up-states at micromolar concentrations. In cultures expressing β2-V287L, no significant effect was observed on the action potential waveform either in the absence or in the presence of pharmacological treatment. Our results show that some aspects of the spontaneous hyperexcitability displayed by a murine model of a human channelopathy can be reproduced in neuronal cultures. In particular, our cultures represent an in vitro chronic model of spontaneous epileptiform activity, i.e., not requiring pre-treatment with convulsants. This opens the way to the study in vitro of the role of β2-V287L on synaptic formation. Moreover, our neocortical cultures on MEA platforms allow to determine the effects of prolonged pharmacological treatment on spontaneous network hyperexcitability (which is impossible in the short-living brain slices). Methods such as the one we illustrate in the present paper should also considerably facilitate the preliminary screening of antiepileptic drugs (AEDs), thereby reducing the number of in vivo experiments.

Blood, Jan 15, 1999

We investigated here the changes in von Willebrand factor (vWF) multimers in recurrent, sporadic ... more We investigated here the changes in von Willebrand factor (vWF) multimers in recurrent, sporadic and familial forms of hemolytic uremic syndrome (HUS)/thrombotic thrombocytopenic purpura (TTP) to see whether they are actually proteolyzed in vivo in these patients. Molecular determinants of fragments in vWF were also characterized to identify possible sites of cleavage of the subunit. Unusually large vWF multimers were found in blood of 8 of 10 patients with recurrent HUS/TTP, both in the acute phase and in remission, but never in familial and sporadic cases. Instead, all of the groups showed evidence of enhanced fragmentation of vWF multimers during the acute phase. Increased fragmentation was also shown by decrease in native 225-kD vWF subunit. In recurrent and sporadic HUS/TTP, enhanced fragmentation normalized at remission, but the abnormality persisted in familial HUS/TTP patients. The latter findings suggest that patients with familial HUS/TTP may have a congenital abnormality ...

Nephrology Dialysis Transplantation, 1999

Autosomal dominant medullary cystic disease (ADMCKD) is an interstitial nephropathy which shares ... more Autosomal dominant medullary cystic disease (ADMCKD) is an interstitial nephropathy which shares morphological and clinical features with recessive nephronophthisis. Recently, a locus on chromosome 1 was associated to ADMCKD in two large Cypriot families in which the disease was associated with hyperuricemia and gout. We studied a four-generation Italian family which included 10 members (4 males; 6 females) affected by ADMCKD and hyperuricemia and gout. Diagnostic criteria included 1) autosomal dominant inheritance 2) defect of urine concentration 3) normal or small-sized kidneys with occasional small medullary cysts 4) tubular interstitial fibrosis and tubular atrophy. We therefore considered this pedigree for linkage mapping, which has been accomplished by 358 fluorescence-labeled polymorphic markers covering the whole genome. The ADMCKD2 locus has been identified on chromosome 16p12, with a maximum LOD score value of 3.86 for marker D16S3036. The critical region spans 10.5 cM and includes several known genes. The identification of the new ADMCKD2 locus and evidence of genetic heterogeneity notwithstanding the shared common phenotype will further contribute to the understanding of cystic disease pathogenesis.

Nature Genetics, 2012

Consortium. 15 Biobanca e Registro Clinico per l'Emiplegia Alternante (I.B.AHC) Consortium. 16 Th... more Consortium. 15 Biobanca e Registro Clinico per l'Emiplegia Alternante (I.B.AHC) Consortium. 16 The European Network for Research on Alternating Hemiplegia (ENRAH) for Small-and-Medium sized Enterprises (SME) Consortium.

Journal of Hypertension, 1993

Human Molecular Genetics, 1996

Hirschsprung disease (HSCR), or aganglionic megacolon, is the most common cause of congenital int... more Hirschsprung disease (HSCR), or aganglionic megacolon, is the most common cause of congenital intestinal obstruction. Two different loci have been found to be tightly linked to HSCR on chromosomes 10 and 13, respectively. Recently, mutations in the RET protooncogene on chromosome 10q11.2 were identified in several HSCR patients. In addition, a missense mutation in the endothelin-B receptor (EDNRB) gene on chromosome 13q22 was found in an inbred Mennonite kindred affected by HSCR and associated abnormalities, demonstrating the involvement of EDNRB in HSCR pathogenesis. To test whether mutations in the EDNRB gene could account for Hirschsprung in patients from non-inbred populations, we analysed DNA samples from 17 probands of Italian origin with HSCR. We have identified two novel EDNRB mutations: a missense mutation in a sporadic case, S305N, which leads to a change of a serine to an asparagine, disrupting a putative phosphorylation site; and a single nucleotide deletion in a familial case, N378I, resulting in a truncated protein. Both mutations were found in one of the healthy parents, and neither of these mutations were found in any of the normal individuals tested. These data confirm the involvement of EDNRB in HSCR pathogenesis and demonstrate that EDNRB mutations could contribute to HSCR disease in non-inbred populations.

Human Molecular Genetics, 2009

Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is a focal form of epilepsy character... more Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is a focal form of epilepsy characterized by seizures occurring during non-REM sleep. We have developed and characterized the first mouse model for ADNFLE type III carrying the V287L mutation of the b2 subunit of neuronal nicotinic receptor. Mice expressing mutant receptors show a spontaneous epileptic phenotype by electroencephalography with very frequent interictal spikes and seizures. Expression of the mutant b2 subunit is driven by a neuronal-specific tetracycline-controlled promoter, which allows planned silencing of transgene expression in a reversible fashion and tracking the involvement of mutant receptor in crucial phases of epileptogenesis. We found that restricted silencing during development is sufficient to prevent the occurrence of epileptic seizures in adulthood. Our data indicate that mutant nicotinic receptors are responsible for abnormal formation of neuronal circuits and/or long-lasting alteration of network assembly in the developing brain, thus leading to epilepsy.

Clinical and Experimental Pharmacology and Physiology, 1995

ABSTRACT Summary1. Previous studies on the pathogenetic mechanisms of hypertension in the Milan h... more ABSTRACT Summary1. Previous studies on the pathogenetic mechanisms of hypertension in the Milan hypertensive strain of rat (MHS) showed that a polymorphism within the α-adducin gene is responsible for up to 50% of the blood pressure difference between MHS and their MNS normotensive control strain. A case-control study has shown also in humans an association between α-adducin locus and hypertension using 4 multiallelic markers surrounding the α-adducin locus.2. With a multiple regression approach we provide an estimate of the contribution of the genotype for each marker to the blood pressure variability in comparison to that provided by sex, body mass index and age.3. While sex, body mass index and age contributed by about 40–45% to the overall blood pressure variability, the inclusion of the genotype for the marker closer to the α-adducin locus provided a further increase of the variability explained of about 5%.4. The contribution independently provided by the other markers decreased exponentially with the increase of distance from α-adducin locus.

Cephalalgia, 2013

Objective The objective of this article is to evaluate electrically evoked thresholds for cortica... more Objective The objective of this article is to evaluate electrically evoked thresholds for cortical spreading depression (CSD) and stress-induced activation of trigeminal afferents in a rat model of medication-overuse headache (MOH). Methods Sumatriptan or saline was delivered subcutaneously by osmotic minipump for six days to Sprague-Dawley rats. Two weeks after pump removal, animals were anesthetized and recording/stimulating electrodes implanted. The animals were pretreated with vehicle or topiramate followed by graded electrical stimulation within the visual cortex. CSD events were identified by decreased EEG amplitude and DC potential shift. Additional unanesthetized sumatriptan or saline-pretreated rats were exposed to bright light environmental stress and periorbital and hindpaw withdrawal thresholds were measured. Following CSD stimulation or environmental stress, immunohistochemical staining for Fos in the trigeminal nucleus caudalis (TNC) was performed. Results Sumatriptan ...