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1.
Orphanet J Rare Dis ; 11(1): 132, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27682832

RESUMO

BACKGROUND: Rett Syndrome is a neurodevelopmental disorder almost exclusively affecting females, characterized by a broad clinical spectrum of signs and symptoms and a peculiar course. The disease affects different body systems: nervous, muscolo-skeletal, gastro-enteric. Moreover, part of the symptoms are related to the involvement of the autonomic nervous system. In the Tuscany Rett Center at Versilia Hospital, we collected data from 151 subjects with a clinical diagnosis of classical or variant RTT syndrome. For each subject, we assessed the severity of the condition with clinical-rating scales (ISS, PBZ), we quantified the performance of the autonomic nervous system, and we performed genetic analysis. We used multivariate statistical analysis of the data to evaluate the relation between the different clinical RTT forms, the cardiorespiratory phenotype, the different genetic mutations and the severity of the clinical picture. Individuals were classified according to existing forms: Classical RTT and three atypical RTT: Z-RTT, Hanefeld, Congenital. A correlation between C-Terminal deletions and lower severity of the clinical manifestations was evident, in the previous literature, but, considering the analysis of autonomic behaviour, the original classification can be enriched with a more accurate subdivision of Rett subgroups, which may be useful for early diagnosis. RESULTS: Present data emphasize some differences, not entirely described in the literature, among RTT variants. In our cohort the Z-RTT variant cases show clinical features (communication, growth, epilepsy and development), well documented by specific ISS items, less severe, if compared to classical RTT and show autonomic disorders, previously not reported in the literature. In this form epilepsy is rarely present. In contrast, Hanefeld variant shows the constant presence of epilepsy which has an earlier onset In Hanefeld variant the frequency of apneas was rare and, among the cardiorespiratory phenotypes, the feeble type is lacking. CONCLUSION: A quantitative analysis of the different autonomic components reveals differences across typical and atypical forms of RTT that leads to a more accurate classification of the groups. In our cohort of RTT individuals, the inclusion of autonomic parameter in the classification leads to an improved diagnosis at earlier stages of development.

2.
Mol Ecol Resour ; 15(5): 1256-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26261041

RESUMO

This article documents the public availability of transcriptomic resources for (i) the stellate sturgeon Acipenser stellatus, (ii) the flowering plant Campanula gentilis and (iii) two endemic Iberian fish, Squalius carolitertii and Squalius torgalensis.


Assuntos
Campanulaceae/genética , Peixes/genética , Transcriptoma , Animais
3.
Mol Ecol Resour ; 14(3): 489-98, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24219811

RESUMO

Overexploitation of wild populations due to the high economic value of caviar has driven sturgeons to near extinction. The high prices commanded by caviar on world markets have made it a magnet for illegal and fraudulent caviar trade, often involving low-value farmed caviar being sold as top-quality caviar. We present a new molecular approach for the identification of pure sturgeon species and hybrids that are among the most commercialized species in Europe and North America. Our test is based on the discovery of species-specific single nucleotide polymorphisms (SNPs) in the ribosomal protein S7, supplemented with the Vimentin gene and the mitochondrial D-loop. Test validations performed in 702 specimens of target and nontarget sturgeon species demonstrated a 100% identification success for Acipenser naccarii, A. fulvescens, A. stellatus, A. sinensis and A. transmontanus. In addition to species identification, our approach allows the identification of Bester and AL hybrids, two of the most economically important hybrids in the world, with 80% and 100% success, respectively. Moreover, the approach has the potential to identify many other existing sturgeon hybrids. The development of a standardized sturgeon identification tool will directly benefit trade law enforcement, providing the tools to monitor and regulate the legal trade of caviar and protect sturgeon stocks from illicit producers and traders, hence contributing to safeguarding this group of heavily threatened species.


Assuntos
Ovos/classificação , Peixes/classificação , Peixes/genética , Reação em Cadeia da Polimerase/métodos , Animais , Ovos/economia , Espécies em Perigo de Extinção/economia , Espécies em Perigo de Extinção/legislação & jurisprudência , Feminino , Proteínas de Peixes/genética , Contaminação de Alimentos/análise , Contaminação de Alimentos/economia , Marcadores Genéticos , Hibridização Genética , Masculino , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único
4.
Mol Ecol ; 22(11): 3112-23, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23473098

RESUMO

Caviar-producing sturgeons belonging to the genus Acipenser are considered to be one of the most endangered species groups in the world. Continued overfishing in spite of increasing legislation, zero catch quotas and extensive aquaculture production have led to the collapse of wild stocks across Europe and Asia. The evolutionary relationships among Adriatic, Russian, Persian and Siberian sturgeons are complex because of past introgression events and remain poorly understood. Conservation management, traceability and enforcement suffer a lack of appropriate DNA markers for the genetic identification of sturgeon at the species, population and individual level. This study employed RAD sequencing to discover and characterize single nucleotide polymorphism (SNP) DNA markers for use in sturgeon conservation in these four tetraploid species over three biological levels, using a single sequencing lane. Four population meta-samples and eight individual samples from one family were barcoded separately before sequencing. Analysis of 14.4 Gb of paired-end RAD data focused on the identification of SNPs in the paired-end contig, with subsequent in silico and empirical validation of candidate markers. Thousands of putatively informative markers were identified including, for the first time, SNPs that show population-wide differentiation between Russian and Persian sturgeons, representing an important advance in our ability to manage these cryptic species. The results highlight the challenges of genotyping-by-sequencing in polyploid taxa, while establishing the potential genetic resources for developing a new range of caviar traceability and enforcement tools.


Assuntos
Peixes/classificação , Peixes/genética , Polimorfismo de Nucleotídeo Único/genética , Animais , Sequência de Bases , Espécies em Perigo de Extinção , Marcadores Genéticos , Genômica , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Repetições de Microssatélites , Análise de Sequência de DNA
5.
Mol Phylogenet Evol ; 63(3): 857-65, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22425706

RESUMO

The aim of our study is to examine the phylogenetic relationship, divergence times and demographic history of the five close-related Mediterranean and North-eastern Atlantic species/forms of Atherina using the full Bayesian framework for species tree estimation recently implemented in ∗BEAST. The inference is made possible by multilocus data using three mitochondrial genes (12S rRNA, 16S rRNA, control region) and one nuclear gene (rhodopsin) from multiple individuals per species available in GenBank. Bayesian phylogenetic analysis of the complete gene dataset produced a tree with strong support for the monophyly of each species, as well as high support for higher level nodes. An old origin of the Atherina group was suggested (19.2 MY), with deep split events within the Atherinidae predating the Messinian Salinity Crisis. Regional genetic substructuring was observed among populations of A. boyeri, with AMOVA and MultiDimensional Scaling suggesting the existence of five groupings (Atlantic/West Mediterranean, Adriatic, Greece, Black Sea and Tunis). The level of subdivision found might be consequence of the hydrographic isolation within the Mediterranean Sea. Bayesian inference of past demographic histories showed a clear signature of demographic expansion for the European coast populations of A. presbyter, possibly linked to post-glacial colonizations, but not for the Azores/Canary Islands, which is expected in isolated populations because of the impossibility of finding new habitats. Within the Mediterranean, signatures of recent demographic expansion were only found for the Adriatic population of A. boyeri, which could be associated with the relatively recent emergence of the Adriatic Sea.


Assuntos
Teorema de Bayes , Filogenia , Smegmamorpha/genética , Animais , Oceano Atlântico , Genes Mitocondriais , Variação Genética , Região de Controle de Locus Gênico/genética , Mar Mediterrâneo , Modelos Genéticos , Tipagem de Sequências Multilocus , Análise Multivariada , RNA Ribossômico/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
Mol Phylogenet Evol ; 61(1): 71-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21693193

RESUMO

Sand-smelts are small fishes inhabiting inshore, brackish and freshwater environments and with a distribution in the eastern Atlantic and Mediterranean Sea, extending south into the Indian Ocean. Here, we present a broad phylogenetic analysis of the genus Atherina using three mitochondrial (control region, 12S and 16S) and two nuclear markers (rhodopsin and 2nd intron of S7). Phylogenetic analyses fully support the monophyly of the genus. Two anti-tropical clades were identified, separating the South African Atherina breviceps from the north-eastern Atlantic and Mediterranean Atherina' species. In European waters, two groups were found. The first clade formed by a well supported species-pair: Atherina presbyter (eastern Atlantic) and Atherina hepsetus (Mediterranean), both living in marine waters; a second clade included Atherina boyeri (brackish and freshwater environments) and two independent lineages of marine punctated and non-punctated fishes, recently proposed as separate species. Sequence divergence values strongly suggest multiple species within the A. boyeri complex.


Assuntos
DNA Mitocondrial/genética , Rodopsina/genética , Smegmamorpha/classificação , Smegmamorpha/genética , Animais , Sequência de Bases , Evolução Molecular , Água Doce , Especiação Genética , Geografia , Mitocôndrias/genética , Tipagem de Sequências Multilocus , Filogenia , RNA Ribossômico/genética , RNA Ribossômico 16S/genética , Água do Mar , Análise de Sequência de DNA , Smegmamorpha/fisiologia
7.
Mol Ecol Resour ; 11(3): 586-9, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21457476

RESUMO

This article documents the addition of 238 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Alytes dickhilleni, Arapaima gigas, Austropotamobius italicus, Blumeria graminis f. sp. tritici, Cobitis lutheri, Dendroctonus ponderosae, Glossina morsitans morsitans, Haplophilus subterraneus, Kirengeshoma palmata, Lysimachia japonica, Macrolophus pygmaeus, Microtus cabrerae, Mytilus galloprovincialis, Pallisentis (Neosentis) celatus, Pulmonaria officinalis, Salminus franciscanus, Thais chocolata and Zootoca vivipara. These loci were cross-tested on the following species: Acanthina monodon, Alytes cisternasii, Alytes maurus, Alytes muletensis, Alytes obstetricans almogavarii, Alytes obstetricans boscai, Alytes obstetricans obstetricans, Alytes obstetricans pertinax, Cambarellus montezumae, Cambarellus zempoalensis, Chorus giganteus, Cobitis tetralineata, Glossina fuscipes fuscipes, Glossina pallidipes, Lysimachia japonica var. japonica, Lysimachia japonica var. minutissima, Orconectes virilis, Pacifastacus leniusculus, Procambarus clarkii, Salminus brasiliensis and Salminus hilarii.


Assuntos
Bases de Dados Genéticas , Fungos/classificação , Repetições de Microssatélites , Plantas/classificação , Animais , Fungos/genética , Dados de Sequência Molecular , Plantas/genética , Análise de Sequência de DNA
9.
Mol Ecol ; 12(12): 3253-64, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14629343

RESUMO

Although analyses of intraspecific variability are an important prerequisite for species identification assays, only a few studies have focused on population genetics and historical biogeography of sturgeon species. Here we present the first study on genetic variability of the last remaining Adriatic sturgeon, Acipenser naccarii, derived from mitochondrial and nuclear DNA. Our mitochondrial DNA analyses arranged individuals into three distinguished mitochondrial DNA haplogroups (Po1, Po2 and Buna). Two haplogroups (Po1 and Buna) were correlated to geographical distribution, whereas the third (Po2) was not. It was, however, very closely related to one lineage of its Ponto-Caspian sister species, A. gueldenstaedtii. The distribution of nuclear markers (microsatellites and amplified fragment length polymorphism) was strongly correlated to geographical distribution. An assignment test based on nuclear data placed no specimen of A. naccarii to A. gueldenstaedtii and vice versa. Therefore, the presence of gueldenstaedtii-like haplotypes within the Po population is either the result of a postglacial introgression or an ancestral polymorphism and does not indicate a hybrid population. The most valuable tool for forensic species identification purposes is one diagnostic deletion separating all A. naccarii from A. gueldenstaedtii. As both A. naccarii populations are genetically differentiated, stocking of sturgeon from the Po River in Italy into waters of the Buna River would jeopardize the genetic differences between both populations and should thus be avoided.


Assuntos
Peixes/genética , Variação Genética , Genética Populacional , Geografia , Filogenia , Animais , Sequência de Bases , Primers do DNA , DNA Mitocondrial/genética , Haplótipos/genética , Mar Mediterrâneo , Repetições de Microssatélites/genética , Dados de Sequência Molecular , Polimorfismo de Fragmento de Restrição , Dinâmica Populacional , Análise de Sequência de DNA , Especificidade da Espécie
10.
Sarcoidosis Vasc Diffuse Lung Dis ; 19(1): 54-8, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12002386

RESUMO

BACKGROUND AND AIM OF THE WORK: Bronchoalveolar lavage (BAL) is useful in diagnosis and management of interstitial lung diseases. Glutathione (GSH) represents an important defence molecule against reactive oxygen species produced during inflammation, which underlies both idiopathic pulmonary fibrosis (IPF) and sarcoidosis. Nitric oxide has been suggested as a marker of airway inflammation. The aim of this study was to examine the content of GSH and NO stable metabolites, nitrite/nitrate, in the BAL of a group of patients with IPF and sarcoidosis. METHODS: BAL was performed in 13 patients with newly diagnosed IPF, 13 patients with sarcoidosis and 4 controls. Total GSH and nitrite/nitrate were measured. BAL was repeated, in 5 patients with IPF, after 6 and 12 months and GSH was measured again. RESULTS: IPF patients had significantly lower levels of total GSH compared to sarcoidosis patients or controls (129 +/- 22 vs. 324 +/- 40 and 383 +/- 23 mM; p < 0.001) in the epithelial lining fluid (ELF). In patients with IPF (n = 5), total GSH levels in the ELF increased after 6 and 12 months (T0 = 98 +/- 19; T6 = 219 +/- 22; T12 = 301 +/- 34 microM; p < 0.05) following therapy with immunosuppressive drugs such as corticosteroids, methotrexate, cyclosporin A. Levels of nitrite/nitrate were found significantly elevated in IPF (n = 8) and sarcoidosis (n = 10) patients compared to controls (230 +/- 37 and 216 +/- 36 vs. 86 +/- 11 microM; p < 0.05). CONCLUSION: These observations support the role of inflammation and antioxidant defences in interstitial lung diseases and may provide insights into the pathogenesis of oxidant-induced interstitial disease and their therapy.


Assuntos
Líquido da Lavagem Broncoalveolar/química , Glutationa/análise , Nitratos/análise , Nitritos/análise , Fibrose Pulmonar/diagnóstico , Sarcoidose Pulmonar/diagnóstico , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
Mol Ecol ; 10(9): 2355-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11555277

RESUMO

The identification of interspecific hybrids represents an important issue for conservation biology and trade controls. In Italy, the commercial demand for sturgeon is rapidly increasing and interspecific hybrids represent a relevant part of aquacultural production. In this study we tested the suitability of the amplified fragment length polymorphism (AFLP) technique for sturgeon hybrid detection. Multilocus AFLP profiles were analysed by cluster analysis and assignment tests based on observed and simulated samples. Our results show that this approach can easily identify sturgeon hybrids, encouraging its application not only in sturgeon but also in other systematic groups.


Assuntos
Peixes/genética , Hibridização Genética , Polimorfismo de Fragmento de Restrição , Animais , Conservação dos Recursos Naturais , Peixes/classificação , Itália , Filogenia
13.
Chromosome Res ; 9(1): 47-52, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11272791

RESUMO

The Hind III satellite DNA family, isolated from the Acipenser naccarii genome, was used as a probe for fluorescent in-situ hybridization (FISH) on the karyotype of seven sturgeon species, six belonging to the genus Acipenser and one to Huso. All species except one (A. sturio) exhibit from 8 to 80 chromosome hybridization signals, mainly localized at the pericentromeric regions. Eight chromosomes with weak hybridization signals are present in H. huso and A. ruthenus, which are characterized by a karyotype with about 120 chromosomes. The species with 240-260 chromosomes, A. transmontanus, A. naccarii, A. gueldenstaedtii, and A. baerii, show from 50 to 80 signals, prevalently localized around centromeres. Moreover, A. transmontanus and A. gueldenstaedtii show from 4 to 8 chromosomes with a double signal. The phylogenetic and evolutionary relationships among sturgeon species are discussed on the basis of number and morphology of signal-bearing chromosomes and on the localization of signals.


Assuntos
DNA Satélite/genética , Evolução Molecular , Peixes/genética , Animais , Centrômero , Mapeamento Cromossômico , Hibridização in Situ Fluorescente , Cariotipagem , Metáfase , Filogenia , Ploidias , Especificidade da Espécie
14.
Genetica ; 111(1-3): 359-73, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11841180

RESUMO

The aim of this review is to introduce current knowledge in the field of sturgeon genetics. The first section deals with sturgeon cytogenetics, reviewing karyotype organization and polyploidization events during evolution of Acipenseriformes. The second section concerns the results of applications of molecular biology to studies of phylogenetic relationships between extant species, intraspecific analysis of wild populations and stocks for conservation purposes, together with characterization of molecular markers for species identification, relevant to forensic and conservation issues.


Assuntos
Peixes/genética , Animais , Bandeamento Cromossômico , DNA Satélite/genética , Marcadores Genéticos , Especificidade da Espécie
15.
Life Sci ; 66(24): PL339-44, 2000 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-10864104

RESUMO

The effect of melatonin on hydrogen peroxide- induced broncho-and vasoconstriction was examined in vivo in the model of the isolated, perfused and ventilated lung. The administration of hydrogen peroxide (500 microM) to the perfusate caused a marked decrease in lung compliance, conductance and flow rate. The administration of melatonin (500 microM) to the perfusate 20 min before and during the hydroperoxide exposure did not cause any change in lung function. Exposure of lung microsomes to hydrogen peroxide (1-100 microM) did not induce any significant increase in malonaldehyde (MDA), an index of lipid peroxidation, and it was not affected by treatment with melatonin (500 microM). On the other hand, brain microsomes exposed to hydrogen peroxide (1-100 microM) give rise to increased levels of MDA, which were decreased by pre-treatment with melatonin (500 microM). The results suggest that melatonin may exert an antioxidant effect in conditions were lipid peroxidation is occurring. Its use may not be relevant in conditions where the mechanisms of the reactive oxygen species damage appears to be lipid peroxidation independent, such as the case of hydrogen peroxide induced broncho- and vasoconstriction.


Assuntos
Broncoconstrição/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Pulmão/efeitos dos fármacos , Melatonina/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Broncoconstrição/fisiologia , Peróxido de Hidrogênio/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Pulmão/irrigação sanguínea , Pulmão/metabolismo , Masculino , Malondialdeído/metabolismo , Microssomos/efeitos dos fármacos , Microssomos/metabolismo , Perfusão , Ratos , Ratos Wistar , Testes de Função Respiratória , Vasoconstrição/efeitos dos fármacos , Vasoconstrição/fisiologia
16.
Arch Environ Contam Toxicol ; 38(3): 357-61, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10667934

RESUMO

The effects of chronic exposure to dietary cadmium on the levels of hepatic glutathione (GSH) and on the activity of the glutathione peroxidase enzymes (GSH-Px) were studied for the first time in starlings (Sturnus vulgaris). Thirty-three individuals (17 females and 16 males) were divided into three groups: One represented the untreated control and two were respectively fed with diets containing 10 and 50 ppm cadmium chloride (CdCl(2)). The total duration of treatment was 22 weeks. The three groups respectively accumulated mean hepatic Cd residues of 2.29, 75.71, and 208.49 ppm. Hepatic GSH increased in the treated groups respectively 24% and 52% in comparison to controls. Total GSH-Px activity in the liver was inhibited in the group fed with 50 ppm, due to inhibition of the selenium-dependent fraction of the enzyme, while the selenium-independent fraction did not change significantly. During the treatment, after 14 weeks of exposure to cadmium, the 50 ppm-treated group showed a 47% decrease of the activity of the selenium-dependent GSH-Px and a 50% increase of the somatic liver index in comparison with controls.


Assuntos
Cádmio/efeitos adversos , Dieta , Poluentes Ambientais/efeitos adversos , Glutationa Peroxidase/metabolismo , Aves Canoras/fisiologia , Animais , Feminino , Glutationa/análise , Glutationa Peroxidase/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino
17.
Mol Ecol ; 9(2): 229-32, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10672167

RESUMO

The random amplified polymorphic DNA (RAPD) technique was applied to settle a lawsuit involving unauthorized commercialization of a patented strawberry variety of high economical relevance ('Marmolada'). Because of economical involvements, the molecular approach was added to the more traditional morphological examination in a double-blind test. All plants belonging to the patented variety were unambiguously identified (13 plants among a total of 31 plants examined). The results were accepted as evidence in the court. This study confirms that the RAPD technique is especially suitable for identification of asexually reproduced plant varieties for forensic or agricultural purposes.


Assuntos
Frutas/classificação , Frutas/genética , Patentes como Assunto , Técnica de Amplificação ao Acaso de DNA Polimórfico , Marcadores Genéticos
18.
Cancer Genet Cytogenet ; 113(2): 177-9, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10484987

RESUMO

The dysplastic nevus is considered to be a precursor lesion of melanoma, representing one of the first steps in the progressive transformation from normal melanocyte to melanoma. Various risk degrees of developing cutaneous melanoma in patients with dysplastic nevi have been advanced, based on the presence of dysplastic nevi or melanoma or both in members of the patient's family. We report on the cytogenetic study of three nevi in a young patient with a family history of melanoma. Each nevus showed a simple clonal chromosome change. The t(6;15)(q13;q21) translocation found in one of them seems of particular significance in view of the fact that a similar one, with breakpoint at 6q13 was reported both in an acquired nevus from a patient with a family history of melanoma and in a case of cutaneous metastatic melanoma. These observations seem to support the hypothesis of the existence of a biological continuum between normal melanocyte and melanoma. Furthermore, the finding of chromosome changes similar to those associated with melanoma reinforces the need for a careful follow-up of patients with dysplastic nevi.


Assuntos
Aberrações Cromossômicas/genética , Aberrações Cromossômicas/patologia , Síndrome do Nevo Displásico/genética , Síndrome do Nevo Displásico/patologia , Adulto , Transtornos Cromossômicos , Feminino , Humanos , Hiperplasia , Cariotipagem , Melanócitos/patologia
19.
Heredity (Edinb) ; 83 ( Pt 5): 520-5, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10620023

RESUMO

A karyotype analysis was carried out on the European Atlantic sturgeon, Acipenser sturio (2n=121 +/- 3). The telomeric sequence repeat (TTAGGG)n detected by fluorescent in situ hybridization (FISH) was mostly localized at the telomeres of all chromosomes. Ribosomal DNA (rDNA) genes were detected by silver staining techniques and by FISH with digoxigenin-labelled probe for 28S rDNA. Silver staining detected active NORs in the telomeric regions of six chromosomes, and by FISH one or two additional minor sites were detected. The 5S rDNA was found in the interstitial region of a small metacentric pair. The 5S rRNA gene was completely sequenced for the first time in a sturgeon species. The A. sturio karyotype organization is discussed in relation to phylogenesis of the species within the Acipenseridae and to polyploidization events characterizing sturgeon evolution.


Assuntos
Peixes/genética , Sequências Repetitivas de Ácido Nucleico , Telômero , Animais , Sequência de Bases , Peixes/classificação , Hibridização in Situ Fluorescente/métodos , Cariotipagem , Dados de Sequência Molecular
20.
Chem Biol Interact ; 116(1-2): 93-103, 1998 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-9877203

RESUMO

Paraquat (PQ), a broad spectrum herbicide, produces severe lung inflammation and necrosis resulting in pulmonary fibrosis and respiratory failure. Tachykinins are peptides released by sensory C fibers and have the ability of influencing respiratory functions and cellular proliferation. To examine whether the damage caused by PQ involves tachykinins, rats were depleted in their content of tachykinins by systemic treatment with capsaicin prior to PQ exposure. The animal subjected to this treatment showed a 3-fold higher viability compared to those treated with PQ alone (75 vs 27%). Depletion of reduced glutathione (GSH) is associated with oxidative stress produced by reactive oxygen intermediates during PQ metabolism. This is considered to be critical in the pathogenesis of lung damage by PQ. PQ treatment induced a significant depletion of GSH during the first days and a similar effect was also observed in the group of capsaicin-pretreated rats. Four weeks after PQ treatment the levels of GSH were similar to controls in rat pretreated or not with capsaicin plus PQ. This may indicate that the reduced levels of GSH may be associated to the toxicity observed in the acute phase, but not of importance in the final PQ-induced mortality. Neutral endopeptidase (NEP) is an enzyme considered to be critical in controlling the levels of tachykinins. Exposure of crude membrane preparations of rat lung to PQ resulted in a dose-dependent inhibition of NEP activity. Since NEP inactivation may occur in lung following a PQ exposure in vivo, the results indicate that during PQ intoxication a more sustained activity of tachykinins may be present, producing effects such as cell proliferation, fluid extravasation and bronchoconstriction. In conclusion, this finding supports the hypothesis that neuropeptides released from capsaicin-sensitive nerves could be involved in the modulation of PQ-induced lung damage.


Assuntos
Capsaicina/farmacologia , Herbicidas/toxicidade , Neurônios Aferentes/efeitos dos fármacos , Neurônios Aferentes/fisiologia , Paraquat/toxicidade , Animais , Interações Medicamentosas , Glutationa/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Neprilisina/antagonistas & inibidores , Neprilisina/metabolismo , Neurônios Aferentes/metabolismo , Neuropeptídeos/metabolismo , Neuropeptídeos/fisiologia , Pneumonia/induzido quimicamente , Pneumonia/metabolismo , Ratos , Ratos Sprague-Dawley , Sensibilidade e Especificidade , Taquicininas/metabolismo , Taquicininas/fisiologia
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