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1.
BMC Bioinformatics ; 19(1): 477, 2018 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-30541431

RESUMEN

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. The software is freely available at: https://github.com/frankMusacchia/VarGenius.


Asunto(s)
Biología Computacional/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Análisis de Secuencia de ADN/métodos , Bases de Datos Factuales , Humanos
2.
Langmuir ; 34(29): 8639-8651, 2018 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-29936841

RESUMEN

Amphiphilic cyclodextrins (aCDs) are an intriguing class of carrier systems which, recently, have been proposed to deliver porphyrinoids and anticancer drugs or combined dose of both for dual therapeutic applications. The design of nanoassemblies based on aCD and photosensitizers (PSs) aims to preserve the photodynamic therapy (PDT) efficacy of PS, reducing the tendency of PS to self-aggregate, without affecting the quantum yield of singlet oxygen (1O2) production, and, not less importantly, minimizing dark toxicity and reducing photosensitization effects. With this idea in mind, in this paper, we focus on nanoassemblies between a non-ionic aCD (SC6OH) and halo-alkyl tailored iodinated boron-dipyrromethenes (BODIPY) dye, a class of molecules which recently have been successfully proposed as a stimulating alternative to porphyrinoids for their high photodynamic efficacy. Nanoassemblies of BODIPY/aCD (BL01I@SC6OH) were prepared in different aqueous media by evaporation of mixed organic film of aCD and BODIPY, hydration, and sonication. The nanostructures were characterized, measuring their hydrodynamic diameter and ξ-potential and also evaluating their time-stability in biological relevant media. Taking advantage of emissive properties of the not-iodinated BODIPY analogue (BL01), nanoassemblies based on aCD and BL01 were investigated as model system to get insight on entanglement of BODIPY in the amphiphile in aqueous dispersion, pointing out that BODIPY is well-entrapped in monomeric form (τ ≅ 6.5 ns) within the colloidal carriers. Also morphology and fluorescence emission properties were elucidated after casting the solution on glass. BL01@SC6OH is easily detectable in cytoplasm of HCT116 cell lines, evidencing the remarkable intracellular penetration of this nanoassembly similar to free BODIPY. On the same cell lines, the photodynamically active assembly BL01I/aCD shows toxicity upon irradiation. Despite the fact that free BL01I is more PDT active than its assembly, aCD can modulate the cell uptake of BODIPY, pointing out the potential of this system for in vivo PDT application.

3.
Nat Genet ; 13(2): 167-74, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8640222

RESUMEN

Cross-species comparison is an effective tool used to identify genes and study their function in both normal and pathological conditions. We have applied the power of Drosophila genetics to the vast resource of human cDNAs represented in the expressed sequence tag (EST) database (dbEST) to identify novel human genes of high biological interest. Sixty-six human cDNAs showing significant homology to genes causing Drosophila mutant phenotypes were identified by screening dbEST using the "text string' option, and their map position was determined using both fluorescence in situ hybridization (FISH) and radiation hybrid mapping. Comparison between these genes and their putative partners in Drosophila may provide important insights into their function in mammals. Furthermore, integration of these genes into the transcription map of the human genome contributes to the positional candidate approach for disease gene identification.


Asunto(s)
Mapeo Cromosómico/métodos , Bases de Datos Factuales , Drosophila melanogaster/genética , Homología de Secuencia de Ácido Nucleico , Secuencia de Aminoácidos , Animales , Redes de Comunicación de Computadores , ADN Complementario , Genes de Insecto , Humanos , Células Híbridas/efectos de la radiación , Hibridación Fluorescente in Situ , Modelos Genéticos , Datos de Secuencia Molecular , Mutación , Fenotipo , Alineación de Secuencia/métodos , Homología de Secuencia de Aminoácido
4.
Nat Genet ; 4(3): 221-6, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8358429

RESUMEN

Spinocerebellar ataxia type 1 (SCA1) is an autosomal dominant disorder characterized by neurodegeneration of the cerebellum, spinal cord and brainstem. A 1.2-Megabase stretch of DNA from the short arm of chromosome 6 containing the SCA1 locus was isolated in a yeast artificial chromosome contig and subcloned into cosmids. A highly polymorphic CAG repeat was identified in this region and was found to be unstable and expanded in individuals with SCA1. There is a direct correlation between the size of the (CAG)n repeat expansion and the age-of-onset of SCA1, with larger alleles occurring in juvenile cases. We also show that the repeat is present in a 10 kilobase mRNA transcript. SCA1 is therefore the fifth genetic disorder to display a mutational mechanism involving an unstable trinucleotide repeat.


Asunto(s)
Secuencias Repetitivas de Ácidos Nucleicos , Degeneraciones Espinocerebelosas/genética , Secuencia de Bases , Mapeo Cromosómico , Cromosomas Humanos Par 6 , Clonación Molecular , ADN/genética , Femenino , Humanos , Masculino , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos/genética , Linaje , Reacción en Cadena de la Polimerasa , Transcripción Genética
5.
Nat Genet ; 7(4): 513-20, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7951322

RESUMEN

Spinocerebellar ataxia type 1 (SCA1) is a neurodegenerative disorder caused by expansion of a CAG trinucleotide repeat. In this study, we describe the identification and characterization of the gene harbouring this repeat. The SCA1 transcript is 10,660 bases and is transcribed from both the wild type and SCA1 alleles. The CAG repeat, coding for a polyglutamine tract, lies within the coding region. The gene spans 450 kb of genomic DNA and is organized in nine exons. The first seven fall in the 5' untranslated region and the last two contain the coding region, and a 7,277 basepairs 3' untranslated region. The first four non-coding exons undergo alternative splicing in several tissues. These features suggest that the transcriptional and translational regulation of ataxin-1, the SCA1 encoded protein, may be complex.


Asunto(s)
Genes , Proteínas del Tejido Nervioso/genética , Proteínas Nucleares/genética , Degeneraciones Espinocerebelosas/genética , Empalme Alternativo , Secuencia de Aminoácidos , Ataxina-1 , Ataxinas , Secuencia de Bases , Mapeo Cromosómico , ADN/genética , Cartilla de ADN/genética , Exones , Humanos , Intrones , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Secuencias Repetitivas de Ácidos Nucleicos , Degeneraciones Espinocerebelosas/clasificación
6.
Neuron ; 30(2): 411-22, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11395003

RESUMEN

The proprioceptive system provides continuous positional information on the limbs and body to the thalamus, cortex, pontine nucleus, and cerebellum. We showed previously that the basic helix-loop-helix transcription factor Math1 is essential for the development of certain components of the proprioceptive pathway, including inner-ear hair cells, cerebellar granule neurons, and the pontine nuclei. Here, we demonstrate that Math1 null embryos lack the D1 interneurons and that these interneurons give rise to a subset of proprioceptor interneurons and the spinocerebellar and cuneocerebellar tracts. We also identify three downstream genes of Math1 (Lh2A, Lh2B, and Barhl1) and establish that Math1 governs the development of multiple components of the proprioceptive pathway.


Asunto(s)
Encéfalo/embriología , Interneuronas/fisiología , Propiocepción/fisiología , Médula Espinal/embriología , Factores de Transcripción/metabolismo , Animales , Apoptosis , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Tipificación del Cuerpo , Encéfalo/fisiología , Cerebelo/embriología , Cerebelo/fisiología , Desarrollo Embrionario y Fetal , Regulación del Desarrollo de la Expresión Génica , Secuencias Hélice-Asa-Hélice , Heterocigoto , Proteínas de Homeodominio/genética , Proteínas con Homeodominio LIM , Ratones , Ratones Noqueados , Ratones Transgénicos , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Propiocepción/genética , Proteínas Represoras , Piel/inervación , Médula Espinal/fisiología , Factores de Transcripción/deficiencia , Factores de Transcripción/genética , beta-Galactosidasa/genética
7.
J Med Genet ; 42(7): e47, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15994872

RESUMEN

Retinitis pigmentosa is the most common form of retinal degeneration and is heterogeneous both clinically and genetically. The autosomal dominant forms (ADRP) can be caused by mutations in 12 different genes. This report describes the first simultaneous mutation analysis of all the known ADRP genes in the same population, represented by 43 Italian families. This analysis allowed the identification of causative mutations in 12 of the families (28% of the total). Seven different mutations were identified, two of which are novel (458delC and 6901C-->T (P2301S), in the CRX and PRPF8 genes, respectively). Several novel polymorphisms leading to amino acid changes in the FSCN2, NRL, IMPDH1, and RP1 genes were also identified. Analysis of gene prevalences indicates that the relative involvement of the RHO and the RDS genes in the pathogenesis of ADRP is less in Italy than in US and UK populations. As causative mutations were not found in over 70% of the families analysed, this study suggests the presence of further novel genes or sequence elements involved in the pathogenesis of ADRP.


Asunto(s)
Genes Dominantes , Retinitis Pigmentosa/genética , Adolescente , Adulto , Edad de Inicio , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Proteínas Portadoras/genética , Niño , Preescolar , Análisis Mutacional de ADN , Proteínas de Unión al ADN/genética , Proteínas del Ojo/genética , Familia , Frecuencia de los Genes , Proteínas de Homeodominio/genética , Humanos , Italia/epidemiología , Proteínas Asociadas a Microtúbulos , Persona de Mediana Edad , Mutación , Prevalencia , Proteínas de Unión al ARN , Retinitis Pigmentosa/clasificación , Retinitis Pigmentosa/epidemiología , Rodopsina/genética , Transactivadores/genética
8.
Eur J Ophthalmol ; 16(5): 779-81, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17061239

RESUMEN

PURPOSE: To report the clinical and functional characteristics of an autosomal dominant retinitis pigmentosa (ADRP) family with a novel point mutation (P2301S) in the PRPF8 gene. METHODS: PRPF8 gene analysis and complete ophthalmologic examination in an ADRP family. RESULTS: Clinical examination revealed the typical RP phenotype in all family members. Electroretinography showed preserved ERG photopic responses. Genetic analysis showed that the P2301S missense mutation segregated with the disease in all subjects. CONCLUSIONS: Unlike previously reported families, the PRPF8 gene mutation in our family is associated with a mild phenotype in which cone function is partially preserved.


Asunto(s)
Proteínas Portadoras/genética , ADN/genética , Mutación , Retinitis Pigmentosa/genética , Electrorretinografía , Femenino , Humanos , Italia , Masculino , Oftalmoscopía , Linaje , Fenotipo , Proteínas de Unión al ARN , Retinitis Pigmentosa/diagnóstico
9.
Mech Dev ; 100(1): 115-8, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11118895

RESUMEN

vax2 is a recently isolated homeobox gene, that plays an important role in controlling the dorso-ventral patterning of the retina. In this paper we present a thorough description of the Xvax2 expression pattern all along Xenopus embryogenesis, and compare this pattern in detail to that shown by Xvax1b and Xpax2, two genes also involved in ventral eye development. At early neurula stages, while Xpax2 starts to be expressed within the eye field, both Xvax2 and Xvax1b are exclusively activated in the presumptive ventral telencephalon. Since midneurula stages, Xvax2 and Xvax1b are also transcribed in the medial aspect of the eye field. At tailbud and tadpole stages, Xvax2, Xvax1b and Xpax2 expression overlaps in the optic stalk and nerve and in the optic disk, while Xvax2 and Xvax1b also display specific activation domains in the ventral retina as well as in the ventral telencephalon and diencephalon. Finally, during metamorphosis a high level of both Xvax2 and Xvax1b transcription is maintained in the optic chiasm. In addition, Xvax1b is transcribed in the ventral hypothalamus and in the hypophysis, whereas a strong Xvax2 expression is retained in the ventral portion of the mature retina.


Asunto(s)
Ojo/embriología , Proteínas de Homeodominio/biosíntesis , Proteínas de Homeodominio/genética , Retina/embriología , Telencéfalo/embriología , Proteínas de Xenopus , Xenopus laevis/embriología , Animales , Encéfalo/embriología , ADN Complementario/metabolismo , Embrión no Mamífero/metabolismo , Biblioteca de Genes , Hibridación in Situ , Datos de Secuencia Molecular , Factores de Tiempo , Transcripción Genética
10.
Oncogene ; 34(25): 3240-50, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25151966

RESUMEN

MicroRNAs (miRNAs) control cell cycle progression by targeting the transcripts encoding for cyclins, CDKs and CDK inhibitors, such as p27(KIP1) (p27). p27 expression is controlled by multiple transcriptional and posttranscriptional mechanisms, including translational inhibition by miR-221/222 and posttranslational regulation by the SCF(SKP2) complex. The oncosuppressor activity of miR-340 has been recently characterized in breast, colorectal and osteosarcoma tumor cells. However, the mechanisms underlying miR-340-induced cell growth arrest have not been elucidated. Here, we describe miR-340 as a novel tumor suppressor in non-small cell lung cancer (NSCLC). Starting from the observation that the growth-inhibitory and proapoptotic effects of miR-340 correlate with the accumulation of p27 in lung adenocarcinoma and glioblastoma cells, we have analyzed the functional relationship between miR-340 and p27 expression. miR-340 targets three key negative regulators of p27. The miR-340-mediated inhibition of both Pumilio family RNA-binding proteins (PUM1 and PUM2), required for the miR-221/222 interaction with the p27 3'-UTR, antagonizes the miRNA-dependent downregulation of p27. At the same time, miR-340 induces the stabilization of p27 by targeting SKP2, the key posttranslational regulator of p27. Therefore, miR-340 controls p27 at both translational and posttranslational levels. Accordingly, the inhibition of either PUM1 or SKP2 partially recapitulates the miR-340 effect on cell proliferation and apoptosis. In addition to the effect on tumor cell proliferation, miR-340 also inhibits intercellular adhesion and motility in lung cancer cells. These changes correlate with the miR-340-mediated inhibition of previously validated (MET and ROCK1) and potentially novel (RHOA and CDH1) miR-340 target transcripts. Finally, we show that in a small cohort of NSCLC patients (n=23), representative of all four stages of lung cancer, miR-340 expression inversely correlates with clinical staging, thus suggesting that miR-340 downregulation contributes to the disease progression.


Asunto(s)
Adenocarcinoma/genética , Adenocarcinoma/patología , Apoptosis/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , MicroARNs/genética , Adenocarcinoma del Pulmón , Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Humanos , Proteínas de Unión al ARN/genética , Regulación hacia Arriba/genética
11.
Neurology ; 45(4): 793-6, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7723972

RESUMEN

The gene for spinocerebellar ataxia type 2 (SCA2) is mapped to chromosome 12q23-24.1. Using D12S79 and D12S105, we performed linkage analysis in nine individuals including six affected members of a four-generation family in which we excluded SCA1 by direct mutation analysis. We obtained a lod score = 2.37 at theta = 0.00 for the compound haplotype. The clinical picture appeared homogeneous, showing the absence of corticospinal signs and the presence of peripheral neuropathy. The present study suggests that this SCA2 family is clinically different from most SCA1 families.


Asunto(s)
Degeneraciones Espinocerebelosas/genética , Adulto , Anciano , Cromosomas Humanos Par 12 , ADN/análisis , Femenino , Ligamiento Genético , Haplotipos , Humanos , Italia , Masculino , Persona de Mediana Edad , Fenotipo , Reacción en Cadena de la Polimerasa
12.
Bone ; 16(4): 435-44, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7605704

RESUMEN

The activity of a novel calcitonin SB 205614 was compared with salmon calcitonin (sCT) and (Asu1,7)-eel calcitonin (ELC) in six different models of osteoclastic bone resorption in vitro and in vivo. SB 205614 is an ELC analogue that has an acetylenic bridge instead of the natural disulphide bridge, rendering the molecule more stable biologically than sCT and equally stable to ELC. Our aim was to determine whether this structural change compromised biologic activity, and if not, whether the increased stability could be used to exploit novel modes of administration. In the in vitro assays of pit formation by disaggregated rat osteoclasts on cortical bone slices (DROcA) and PTH stimulation of 45Ca-release from prelabeled fetal rat bone, no significant differences in activity were observed between the three calcitonins. In the DROcA, IC50s of 0.003, 0.015 and 0.064 pg/ml for sCT, ELC, and SB 205614, respectively, were determined, with total or near complete inhibition observed at 1 pg/ml (0.3 pM). In the assay of PTH-stimulation of 45Ca release, IC50s were measured of 5.5, 4.8, and 12.9 pM for sCT, ELC, and SB 205614, respectively; in every case maximal inhibition (ca. 80%) was observed at 30 and 100 pM. The internationally approved U.S. Pharmacopoeia bioassay of hypocalcemia in the rat following intravenous (IV) administration indicated that SB 205614 had a greater potency than ELC or sCT. More important, a full dose-hypocalcemic response curve demonstrated significantly increased potency compared to sCT or ELC, as the doses causing 15% lowering of serum calcium (approximately 50% of the maximum effect) were 33.9, 25.2, and 12.9 mg/kg for sCT, ELC, and SB 205614, respectively. As a preliminary means of investigating alternative delivery forms of calcitonin, the time course of the hypocalcemic effect was investigated in the rat and rabbit following IV administration, and was compared with that following intranasal (IN) administration (rat and rabbit), and following intracolonic administration (rat only). Maximal effects were similar, whereas in general the hypocalcemic effect of SB 205614 was of a longer duration than the other two calcitonins; this was reflected in a larger area over the curve (AOC). However, following IN administration in the rabbit, where an aerosol delivery device similar to that used in the clinic was used to administer the calcitonins, SB 205614 (100 IU/kg) induced a highly significant two-fold increase in the AOC compared to ELC or sCT. The calcitonins were also compared in assays designed to measure therapeutic efficacy in the rat.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Resorción Ósea/tratamiento farmacológico , Calcitonina/análogos & derivados , Calcitonina/farmacología , Osteoclastos/efectos de los fármacos , Secuencia de Aminoácidos , Animales , Resorción Ósea/patología , Modelos Animales de Enfermedad , Vías de Administración de Medicamentos , Estudios de Evaluación como Asunto , Hipocalcemia/tratamiento farmacológico , Técnicas In Vitro , Masculino , Datos de Secuencia Molecular , Osteoporosis/tratamiento farmacológico , Conejos , Ratas , Ratas Sprague-Dawley , Ratas Wistar
13.
J Med Chem ; 36(26): 4214-20, 1993 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-8277504

RESUMEN

A series of dihydro-1H-pyrrolo[1,2-a]imidazole-2,5(3H,6H)-diones were synthesized. These bicylic derivatives contain both the 2-pyrrolidinone and 4-imidazolidinone nuclei, already recognized as important for cognition enhancing activity. In addition, these structures maintain the backbone of piracetam and oxiracetam with the acetamide side chain restricted in a folded conformation. Their ability to reverse scopolamine-induced amnesia was assessed in a one trial, step-through, passive avoidance paradigm. The main features observed are a potent antiamnestic activity after ip administration (minimal effective dose being between 0.3 and 1 mg/kg ip for most compounds), the presence of a bell-shaped dose-response curve and, generally, a reduction of biological activity after po administration. However, the unsubstituted compound (15, dimiracetam) shows no evidence of a bell-shaped dose-response curve and completely retains activity when given orally, being 10-30 times more potent than the reference drug oxiracetam.


Asunto(s)
Cognición/efectos de los fármacos , Imidazoles/síntesis química , Pirroles/síntesis química , Amnesia/inducido químicamente , Amnesia/tratamiento farmacológico , Animales , Reacción de Prevención/efectos de los fármacos , Imidazoles/farmacología , Imidazoles/uso terapéutico , Masculino , Ratones , Estructura Molecular , Piracetam/química , Conformación Proteica , Pirroles/farmacología , Pirroles/uso terapéutico , Pirrolidinas/química , Pirrolidinas/farmacología , Ratas , Ratas Wistar , Escopolamina , Relación Estructura-Actividad
14.
J Am Soc Mass Spectrom ; 4(3): 249-54, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24234854

RESUMEN

Fast-atom bombardment mass spectrometry has been used to investigate the chemical behavior of Fe(III) and Mn(III) tetraarylporphyrins (TAP) in both the condensed and gas phases and to clarify the mechanisms responsible for the production of positive and negative ions. The differences in the behavior of Fe(III) and Mn(III) complexes in the positive ion mode could be correlated with those in their electronic structures and knowledge of the mechanism for the generation of negatively charged species was applied to characterize the counterion coordinated to the Mn(III)-TAP. Thus, the unprecedented, complete characterization of even complex Mn(III)-TAP was made possible.

15.
J Am Soc Mass Spectrom ; 4(3): 255-8, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24234855

RESUMEN

The chemical behavior of Fe(III) and M(III) tetraarylporphorin (TAP) complexes with N-alkylimidazoles and other suitable ligands was studied by direct reaction in the fast-atom bombardment matrix and in the gas phase. The coordination reaction occurs at the metal center and yields molecular adducts of porphyry/ligand (PL) and PL, stoichiometry. Coordinative competition between free and covalently linked ligands can be used to probe the conformation of "tailed" Mn(III)-TAP.

16.
Psychopharmacology (Berl) ; 106(2): 175-8, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1549645

RESUMEN

The effects exerted by oxiracetam on the disruption of performance induced by scopolamine in the radial arm maze were investigated in overtrained rats. Scopolamine induced a dose-related decrease in the efficiency of responding and an increase of running time. The effect of the SC injection of 0.2 mg/kg scopolamine on the efficiency of responding was antagonized by the IP administration of 30 mg/kg oxiracetam, while the effect on running time induced by the same dose of scopolamine was not. Physostigmine (0.3 mg/kg SC) antagonized both effects of 0.2 mg/kg scopolamine. Methylscopolamine, at the dose of 0.2 mg/kg SC, was devoid of any effect on both parameters. Increasing the dose of methylscopolamine to 0.63 mg/kg did cause serious peripheral effects which eventually prevented some animals from completing the task. Similar peripheral effects were observed after administration of 0.63 mg/kg scopolamine. The effects of this dose of scopolamine on efficiency and running time were not antagonized by pretreatment with 100 mg/kg oxiracetam. Oxiracetam alone (30 or 100 mg/kg IP) did not modify the performance of previously trained rats. The present results suggest that oxiracetam selectively restores cholinergic mechanisms which are involved in learning and memory.


Asunto(s)
Memoria/efectos de los fármacos , Psicotrópicos/farmacología , Pirrolidinas/farmacología , Escopolamina/antagonistas & inhibidores , Animales , Relación Dosis-Respuesta a Droga , Masculino , Actividad Motora/efectos de los fármacos , N-Metilescopolamina , Sistema Nervioso Parasimpático/efectos de los fármacos , Parasimpatolíticos/farmacología , Fisostigmina/farmacología , Ratas , Ratas Endogámicas , Escopolamina/farmacología , Derivados de Escopolamina/farmacología
17.
Br J Ophthalmol ; 87(9): 1130-4, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12928282

RESUMEN

AIMS: To describe the clinical phenotype of X linked juvenile retinoschisis in eight Italian families with six different mutations in the XLRS1 gene. METHODS: Complete ophthalmic examinations, electroretinography and A and B-scan standardised echography were performed in 18 affected males. The coding sequences of the XLRS1 gene were amplified by polymerase chain reaction and directly sequenced on an automated sequencer. RESULTS: Six different XLRS1 mutations were identified; two of these mutations Ile81Asn and the Trp122Cys, have not been previously described. The affected males showed an electronegative response to the standard white scotopic stimulus and a prolonged implicit time of the 30 Hz flicker. In the families with Trp112Cys and Trp122Cys mutations we observed a more severe retinoschisis (RS) clinical picture compared with the other genotypes. CONCLUSION: The severe RS phenotypes associated with Trp112Cys and to Trp122Cys mutations suggest that these mutations determine a notable alteration in the function of the retinoschisin protein.


Asunto(s)
Proteínas del Ojo/genética , Mutación Missense/genética , Retinosquisis/genética , Adulto , Edad de Inicio , Niño , Preescolar , Electrorretinografía , Genotipo , Humanos , Italia , Masculino , Linaje , Fenotipo , Retinosquisis/patología
18.
Clin Neuropharmacol ; 9 Suppl 3: S19-26, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3594452

RESUMEN

Oxiracetam (4-hydroxy-2-oxo-1-pyrrolidine acetamide) is a novel compound effective in improving learning and memory in normal animals as well as in animals with acute cerebral impairment induced by a variety of noxious stimuli (i.e., electroshock, neurodepressants, metabolic inhibitors, hypoxia). In accordance with a stepwise approach to the pharmacological studies, the compound was also tested in rats with chronic cerebral impairment due to aging, cerebrovascular lesions, and congenital microencephaly. To evaluate the brain telencephalic functions, the learning rate of two conditioned avoidance responses using the pole climbing test and the performance in a multiple-choice water maze were considered. Oxiracetam at doses ranging from 10 to 60 mg/kg i.p. improved the learning rate of these animals with impaired cognitive functions. The compound was active also by oral administration.


Asunto(s)
Encefalopatías/fisiopatología , Procesos Mentales/efectos de los fármacos , Pirrolidinas/farmacología , Envejecimiento/fisiología , Animales , Trastornos Cerebrovasculares/fisiopatología , Femenino , Aprendizaje/efectos de los fármacos , Memoria/efectos de los fármacos , Microcefalia/fisiopatología , Embarazo , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas
19.
Clin Neuropharmacol ; 9 Suppl 3: S39-47, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3594455

RESUMEN

Oxiracetam at 100 and 300 mg/kg i.p. dose levels increased acetylcholine (ACh) utilization in the rat cerebral cortex and hippocampus. ACh utilization was assessed by measuring, with a gas chromatographic method, the decrease in ACh level after inhibiting its synthesis by 15 micrograms intracerebroventricularly (i.c.v.) injection of hemicholinium (HC-3). ACh steady state levels were not affected. Piracetam (300 mg/kg i.p.) also increased ACh utilization in the hippocampus. Repeated daily administration of oxiracetam 100 mg/kg i.p. caused a 31% increase in high-affinity choline uptake (HACU) in the hippocampus. A single administration of 300 mg/kg i.p. of oxiracetam and piracetam also increased HACU rate in the hippocampus. However, the effect of piracetam was over within 3 h, while 3 h after its administration oxiracetam still caused a 40% increase in HACU rate. Oxiracetam (100 mg/kg i.p.) significantly antagonized the impairment in the acquisition of an active-avoidance conditioned response (pole climbing) associated with the inhibition of ACh synthesis by HC-3. These results indicate that oxiracetam enhances the activity of the septohippocampal cholinergic pathways, and to a lesser extent, of the cortical cholinergic network.


Asunto(s)
Acetilcolina/metabolismo , Reacción de Prevención/efectos de los fármacos , Química Encefálica/efectos de los fármacos , Piracetam/farmacología , Pirrolidinas/farmacología , Pirrolidinonas/farmacología , Animales , Corteza Cerebral/metabolismo , Colina/metabolismo , Cuerpo Estriado/metabolismo , Hemicolinio 3/farmacología , Hipocampo/metabolismo , Masculino , Ratas , Ratas Endogámicas
20.
Can J Neurol Sci ; 20(1): 52-5, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8467430

RESUMEN

We performed a double-blind cross-over study with amantadine hydrochloride in 12 patients with Friedreich's disease and 2 with autosomal dominant cerebellar ataxia. Patients were randomly assigned to a placebo-amantadine or amantadine-placebo sequence. The interval between the treatments was two weeks. Patients were graded according to a functional ataxia scoring scale and videotaped in basal conditions and 90 min after a single oral dose of 100 mg amantadine or placebo. Three evaluators independently scored the videotapes. Statistical analysis showed no significant effect of amantadine in Friedreich's disease.


Asunto(s)
Amantadina/uso terapéutico , Ataxia de Friedreich/tratamiento farmacológico , Adolescente , Adulto , Método Doble Ciego , Femenino , Ataxia de Friedreich/fisiopatología , Humanos , Masculino , Desempeño Psicomotor/fisiología
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