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1.
Med Vet Entomol ; 34(1): 74-85, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31674696

RESUMO

Deer keds (Lipoptena spp.) are blood-sucking ectoparasites of domestic and wild animals, and also accidentally of humans. In Europe, five Lipoptena spp. have been recorded, although the lack of specific taxonomic keys has often led to mistaken identification or to missing data. The present study aimed to develop an identification key of the European species and also to identify Lipoptena spp. found on wild ungulates in northern Italy. In total, 390 hippoboscids were collected from Rupicapra rupicapra, Capreolus capreolus, Cervus elaphus and Ovis aries musimon in an Alpine area of Italy. After morphological identification, 140 specimens were subjected to phylogenetic analysis based on mitochondrial (CO1) and nuclear (CAD) gene sequences. Despite the expected presence of slight morphological variations, all specimens examined were identified both microscopically and molecularly as Lipoptena cervi (100% identity for both CO1 and CAD genes). The massive increase in wild ungulate populations can favour the possibility of detecting other species of Lipoptena. The identification keys proposed in the present study may help with monitoring the presence of Lipoptena species, particularly in European countries where this ectoparasite is neglected and for which various data (from diffusion to control methods) are still missing.


Assuntos
Cervos , Dípteros/classificação , Miíase/veterinária , Ruminantes , Animais , Dípteros/fisiologia , Itália , Miíase/parasitologia , Rupicapra , Ovinos
2.
Br Poult Sci ; 59(1): 7-12, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28922013

RESUMO

1. An experiment was conducted to compare 5 different methods for the evaluation of litter moisture. 2. For litter collection and assessment, 55 farms were selected, one shed from each farm was inspected and 9 points were identified within each shed. 3. For each device, used for the evaluation of litter moisture, mean and standard deviation of wetness measures per collection point were assessed. 4. The reliability and overall consistency between the 5 instruments used to measure wetness were high (α = 0.72). 5. Measurement of three out of the 9 collection points were sufficient to provide a reliable assessment of litter moisture throughout the shed. 6. Based on the direct correlation between litter moisture and footpad lesions, litter moisture measurement can be used as a resource based on-farm animal welfare indicator. 7. Among the 5 methods analysed, visual scoring is the most simple and practical, and therefore the best candidate to be used on-farm for animal welfare assessment.


Assuntos
Dermatite/veterinária , Doenças do Pé/veterinária , Abrigo para Animais , Perus/fisiologia , Água/análise , Bem-Estar do Animal , Animais , Dermatite/prevenção & controle , Pisos e Cobertura de Pisos , Doenças do Pé/prevenção & controle , Doenças das Aves Domésticas , Reprodutibilidade dos Testes
3.
Haemophilia ; 20(1): 106-13, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24112640

RESUMO

Factor XI (FXI) deficiency is a rare inherited bleeding disorder invariably caused by mutations in the FXI gene. The disorder is rather frequent in Ashkenazi Jews, in whom around 98% of the abnormal alleles is represented by Glu117X and Phe283Leu mutations. A wide heterogeneity of causative mutations has been previously reported in a few FXI deficient patients from Italy. In this article, we enlarge the knowledge on the genetic background of FXI deficiency in Italy. Over 4 years, 22 index cases, eight with severe deficiency and 14 with partial deficiency, have been evaluated. A total of 21 different mutations in 30 disease-associated alleles were identified, 10 of which were novel. Among them, a novel Asp556Gly dysfunctional mutation was also identified. Glu117X was also detected, as previously reported from other patients in Italy, while again Phe283Leu was not identified. A total of 34 heterozygous relatives were also identified. Bleeding tendency was present in very few cases, being inconsistently related to the severity of FXI deficiency in plasma. In conclusion, at variance with other populations, no single major founder effect is present in Italian patients with FXI deficiency.


Assuntos
Deficiência do Fator XI/genética , Fator XI/genética , Processamento Alternativo , Sequência de Aminoácidos , Substituição de Aminoácidos , Fator XI/química , Deficiência do Fator XI/sangue , Deficiência do Fator XI/diagnóstico , Feminino , Heterogeneidade Genética , Genótipo , Humanos , Itália , Masculino , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Mutação de Sentido Incorreto , Fases de Leitura Aberta , Conformação Proteica , Estabilidade Proteica , Alinhamento de Sequência , População Branca/genética
4.
Haemophilia ; 16(5): 786-90, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20398075

RESUMO

SUMMARY: Analysis of cDNA is a useful way of investigating splicing mutations and provides more information than using in silico analysis to understand disease pathogenesis better. For understanding the manner in which mutations result in haemophilia A (HA) of different degrees of severity in four index cases with HA and splice site mutations, we performed a detailed analysis of F8 lymphocyte mRNA using a nested PCR-approach. A c.601 +5 G>A change in a mild HA patient produces four transcripts at mRNA level: wild-type, one skipping exon 4, one skipping exons 4 and 5 and one skipping exons 4, 5 and 6, while in silico analysis predicts that the splicing score is not reduced significantly. F8 mRNA of a c.1538 -18 G>A mutation in mild HA lacks the first 36 bases (c.1538_1573del36) of exon 11, resulting in a protein lacking the first 12 amino acids coded for by exon 11, while in silico prediction suggests the creation of a new acceptor splice site with the introduction of 16 bp of intron 10 in the reading frame of exon 11. In keeping with in silico prediction, a c.1443 +1 G>C mutation produces a truncated protein of only 465 amino acids and a c.602 -1 G>A change produces the skipping of exon 5 at mRNA level. Both mutations were identified in severe HA. F8 mRNA analysis is a useful tool for the characterization of the mechanisms by which splice site mutations affect the phenotype, while in silico analysis may not be always reliable.


Assuntos
Fator VIII/genética , Hemofilia A/genética , Mutação , Sítios de Splice de RNA/genética , RNA Mensageiro/genética , Cromatografia Líquida de Alta Pressão/métodos , Análise Mutacional de DNA , Humanos
5.
Acta Haematol ; 121(2-3): 106-10, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19506356

RESUMO

For a long time, autosomal recessive inheritance has been considered a unique feature of type 3 von Willebrand disease (VWD), which is characterized by the virtual absence of von Willebrand factor (VWF) in plasma and storage compartments. In recent years, it has been demonstrated that this type of inheritance is also present in some type 1 and 2 families, previously considered the epitome of true dominant transmission. In many patients of these families with recessive VWD, molecular basis studies have provided insights into the molecular mechanisms responsible for the heterogeneity of phenotypes. We report our experience with 12 families with clearly recessive inheritance, but definitely measurable factor VIII and VWF, which is not typical for severe type 3 VWD.


Assuntos
Códon sem Sentido , Genes Recessivos , Mutação de Sentido Incorreto , Mutação Puntual , Doenças de von Willebrand/genética , Fator de von Willebrand/genética , Eletroforese das Proteínas Sanguíneas , Criança , Pré-Escolar , Desamino Arginina Vasopressina/uso terapêutico , Fator VIII/análise , Feminino , Frequência do Gene , Heterogeneidade Genética , Genótipo , Humanos , Lactente , Íntrons/genética , Masculino , Fenótipo , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Sítios de Splice de RNA/genética , Estudos Retrospectivos , Doenças de von Willebrand/classificação , Doenças de von Willebrand/tratamento farmacológico , Fator de von Willebrand/análise , Fator de von Willebrand/química
6.
Haemophilia ; 14(1): 96-102, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18028394

RESUMO

Factor XIII (FXIII) deficiency is a very rare (1:2 000 000) severe autosomal recessive bleeding disorder, mostly due to mutations in the coagulation FXIII A-subunit gene. We have studied the molecular basis of FXIII deficiency in five unrelated Italian families. The coding region, intron-exon boundaries and 5'- and 3'-untranslated regions of the FXIII gene encoding the A subunit were amplified and directly sequenced. Candidate mutations were identified in all the patients. Three novel mutations occurred in three patients. These include a novel homozygous deletion of two base pairs (bp) in exon 14 (c.2002-2003 DelCT). This deletion causes a frameshift from Leu667 and the formation of a stop codon at amino acid position 681. The second patient presents a novel homozygous (c.2126 G>A) transition in exon 15, predicting a Ser708Asn in Barrel 2 domain. The third patient is compound heterozygote for two missense mutations, a previously reported Arg260His substitution, and a novel transition in exon 4 (c.560 C>T) predicting a Pro186Leu in the core domain. The remaining two patients have two previously reported mutations: a 4-bp homozygous deletion in exon 11 (c.1392-1395 Del AATT), previously reported to occur in the Vicenza Area, and a homozygous nonsense mutation in exon 8 (c.979 C>T) predicting an Arg326X in the core domain. The novel mutations occurred at amino acid residues highly conserved among different species (pig, monkey, mouse and dog) and were not detected in 110 normal alleles. Structural analysis shows that Pro186Leu mutation leads to the replacement of the rigid proline pyrrolidine ring by the larger and more flexible leucine side chain and Ser708Asn may probably disrupt the hydrogen bond with Ala291.


Assuntos
Deficiência do Fator XIII/genética , Fator XIII/genética , Mutação , Códon de Terminação , Análise Mutacional de DNA , Saúde da Família , Mutação da Fase de Leitura , Componentes do Gene , Homozigoto , Humanos , Itália , Mutação de Sentido Incorreto , Subunidades Proteicas
8.
Biochim Biophys Acta ; 1310(3): 269-76, 1996 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-8599604

RESUMO

Prostaglandin D synthetase [PGD-S, prostaglandin-H2 D-isomerase, (5Z, 13E)-(15S)-9alpha, 11 alpha-epidioxy-15-hyrdroxyprosta-5,13-dienoate D-isomerase, EC 5,3,99,2], an enzyme that catalyzes the formation of prostaglandin D2, was originally isolated from homogenates of rat brain and spleen and is known to be a membrane-bound enzyme. Subsequent immunohistochemical studies have shown that PGD-S is associated with neurons in the brain of immature rats, whereas in adult rats it is associated with oligodendrocytes. Several recent studies have shown that the beta-trace protein isolated from human cerebrospinal fluid (CSF), the second most abundant protein in human CSF after albumin, is equivalent to PGD-S. In this paper, we report the preparation of a monospecific polyclonal antibody against purified PGD-S isolated from human CSF and the establishment of a specific radioimmunoassay for this protein. Using this radioimmunoassay in conjunction with immunoblot analysis, PGD-S was detected in various biological fluids including serum, aqueous humor, and rete testis fluid. In addition, an antibody prepared against human PGD-S partially cross-reacted with the PGD-S in the rat and ram. Using a monospecific polyclonal antibody prepared against purified rat PGD-S isolated from rat CSF in conjunction with [35S]methionine incorporation and immunoprecipitation techniques, it was shown for the first time that PGD-S is actively synthesized and secreted by astrocytes cultured in vitro, suggesting the astrocyte is the cellular origin of PGD-S in the CSF. The identification of the astrocyte as the cellular origin of this unique enzyme will allow the use of an in vitro system to study its regulation.


Assuntos
Astrócitos/enzimologia , beta-Globulinas/biossíntese , Encéfalo/enzimologia , Oxirredutases Intramoleculares , Isomerases/biossíntese , Envelhecimento , Sequência de Aminoácidos , Animais , Anticorpos , Humor Aquoso/metabolismo , beta-Globulinas/análise , beta-Globulinas/líquido cefalorraquidiano , Ligação Competitiva , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Humanos , Immunoblotting , Isomerases/análise , Isomerases/metabolismo , Lipocalinas , Masculino , Dados de Sequência Molecular , Especificidade de Órgãos , Peptídeos/síntese química , Peptídeos/imunologia , Biossíntese de Proteínas , Coelhos , Radioimunoensaio , Ratos , Reticulócitos , Esquizofrenia/líquido cefalorraquidiano , Testículo/metabolismo
9.
Eur J Cancer ; 39(16): 2403-10, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14556934

RESUMO

This study aimed to assess, in an in vivo experimental model, the growth inhibitory effects of IdB 1016 (Silipide, a complex of silybin/phosphatidylcholine) when used as a single agent against human ovarian cancer. We also wanted to investigate the mechanism of the antiangiogenic action by assessing Vascular Endothelial Growth Factor (VEGF) levels and by using macroarray technology to evaluate the regulation of a panel of genes involved in angiogenesis. We also aimed to establish the plasma and tumour bioavailability of silybin after repeated administration of IdB 1016. Female nude mice bearing human ovarian cancer xenografts (A2780) received 450 mg/kg/day IdB 1016 daily by oral gavage until the end of the study. At sacrifice, blood and tumour specimens were collected and subsequently processed for the determination of silybin levels, VEGF levels or a gene expression profile. IdB 1016 was significantly active in inhibiting ovarian tumour growth. Treatment with 450 mg/kg/day for a total of 20 administrations produced a tumour weight inhibition (TWI%) of 78% and a Log10 Cell Kill (LCK) of 1.1. Free silybin levels were found to be 7.0+/-5.3 microg/ml and 183.5+/-85.9 ng/g tissue (mean+/-standard deviation (S.D.)) in the plasma and tumour samples, respectively. No significant differences were found in the concentration of human VEGF in xenografts from control and IdB 1016-treated mice. The array analysis suggested the downregulation of the VEGR receptor 3 and the upregulation of angiopoietin-2 as potential mechanisms for the antiangiogenic activity. In conclusion, these findings suggest IdB 1016 is a good candidate, with a relevant clinical potential, for use in the management of recurrent ovarian cancer. A phase II, non-randomised clinical study is now ongoing in our Institute aimed at evaluating the efficacy of daily administrations of IdB 1016 in the serological recurrence of ovarian cancer.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Fosfatidilcolinas/uso terapêutico , Silimarina/uso terapêutico , Animais , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , DNA Complementar/metabolismo , Avaliação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Camundongos , Camundongos Nus , Neovascularização Patológica/genética , Neoplasias Ovarianas/irrigação sanguínea , Fosfatidilcolinas/farmacocinética , Silimarina/farmacocinética , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Life Sci ; 63(3): 215-22, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9698051

RESUMO

The hallucinogenic effects of lysergic acid diethylamide (LSD) have mainly been attributed to the interaction of this drug with the serotoninergic system, but it seems more likely that they are the result of the complex interactions of the drug with both the serotoninergic and dopaminergic systems. The aim of the present study was to investigate the functional actions of LSD at dopaminergic receptors using prolactin secretion by primary cultures of rat pituitary cells as a model. LSD produced a dose-dependent inhibition of prolactin secretion in vitro with an IC50 at 1.7x10(-9) M. This action was antagonized by spiperone but not by SKF83566 or cyproheptadine, which indicates that LSD has a specific effect on D2 dopaminergic receptors. The maximum inhibition of prolactin secretion achieved by LSD was lower than that by dopamine (60% versus 80%). Moreover, the fact that LSD at 10(-8)-10(-6) M antagonized the inhibitory effect of dopamine (10(-7) M) and bromocriptine (10(-11) M) suggests that LSD acts as a partial agonist at D2 receptors on lactotrophs in vitro. Interestingly, LSD at 10(-13)-10(-10) M, the concentrations which are 10-1000-fold lower than those required to induce direct inhibition on pituitary prolactin secretion, potentiated the dopamine (10(-10)-2.5x10(-9) M)-mediated prolactin secretion by pituitary cells in vitro. These results suggest that LSD not only interacts with dopaminergic receptors but also has a unique capacity for modulating dopaminergic transmission. These findings may offer new insights into the hallucinogenic effect of LSD.


Assuntos
Dopamina/farmacologia , Dietilamida do Ácido Lisérgico/farmacologia , Hipófise/efeitos dos fármacos , Prolactina/metabolismo , Receptores de Dopamina D2/agonistas , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/análogos & derivados , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/farmacologia , Animais , Bromocriptina/farmacologia , Células Cultivadas , Ciproeptadina/farmacologia , Agonistas de Dopamina/farmacologia , Antagonistas de Dopamina/farmacologia , Feminino , Hipófise/citologia , Hipófise/metabolismo , Ratos , Ratos Wistar
11.
J Pharm Pharmacol ; 49(3): 319-21, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9231354

RESUMO

The dopaminergic and antidopaminergic activity of drugs is frequently assayed in pituitary cell cultures. Here we describe a modified version of the assay based on the use of pituitary cells from prepubertal female rats. Under our experimental conditions (50,000 cells well-1, 2-day culture and 2-h drug-exposure) the assay yielded high selectivity and sensitivity for drug dopaminergic activity. D2 agonistic activity of bromocriptine could be observed at a concentration as low as 10(-15) M, the antagonistic activity of haloperidol at 10(-16) M. The assay also proved reproducible and simple enough for routine screening of dopaminergic activity. The assay enabled dopaminergic agonist and antagonist activity to be revealed at very low drug concentrations. The high sensitivity of the assay could be of advantage in studying dopaminergic activity in samples containing active substances present at low concentrations or for disclosing the activity of substances with low dopaminergic potency.


Assuntos
Agonistas de Dopamina/farmacologia , Antagonistas de Dopamina/farmacologia , Dopamina/farmacologia , Hipófise/efeitos dos fármacos , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/análogos & derivados , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/farmacologia , Animais , Bromocriptina/farmacologia , Contagem de Células/efeitos dos fármacos , Células Cultivadas , Ciproeptadina/farmacologia , Avaliação Pré-Clínica de Medicamentos , Feminino , Haloperidol/farmacologia , Hipófise/citologia , Hipófise/metabolismo , Prolactina/antagonistas & inibidores , Ratos , Ratos Wistar , Espiperona/farmacologia
13.
J Thromb Haemost ; 10(5): 951-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22429825

RESUMO

BACKGROUND: von Willebrand disease (VWD) is caused by mutations in von Willebrand factor (VWF) that have different pathophysiologic effect in causing low plasma VWF levels. Type 1 VWD includes quantitative plasma VWF deficiency with normal VWF structure and function. OBJECTIVES: We report three novel type 1 VWF mutations (A1716P, C2190Y and R2663C) located in different VWF domains that are associated with reduced secretion and reduced formation of elongated Weibel-Palade body (WPB)-like granules. METHODS: Transient expression of recombinant mutant full-length VWF in 293 EBNA cells was performed and secretion, collagen binding and GpIb binding assessed in comparison with wild-type VWF. Expression was also examined in HEK293 cells that form WPB-like granules when transfected with wild-type VWF. RESULTS: Laboratory results and multimer analysis of plasma VWF was compatible with type 1 VWD. Expression experiments demonstrated slightly reduced VWF synthesis and drastically impaired secretion upon homozygous expression. In HEK293 cells, homozygous expression of A1716P and C2190Y VWF variants failed to form elongated WPB-like granules, while R2663C was capable of WPB-like granules. Heterozygous expression of VWF variants had a negative impact on wild-type VWF with a reduction in elongated WPB-like granules in co-transfected cells. CONCLUSIONS: Our results demonstrate that homozygous and heterozygous quantitative VWF deficiency caused by missense VWF mutations in different VWF domains can be associated with inability to form endothelial WPB-like granules.


Assuntos
Corpos de Weibel-Palade/metabolismo , Corpos de Weibel-Palade/patologia , Doença de von Willebrand Tipo 1/patologia , Fator de von Willebrand/metabolismo , Colágeno/metabolismo , Regulação para Baixo , Imunofluorescência , Predisposição Genética para Doença , Células HEK293 , Heterozigoto , Homozigoto , Humanos , Microscopia Confocal , Mutação de Sentido Incorreto , Fenótipo , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Ligação Proteica , Multimerização Proteica , Transfecção , Doença de von Willebrand Tipo 1/sangue , Doença de von Willebrand Tipo 1/genética , Fator de von Willebrand/genética
14.
J Thromb Haemost ; 9(8): 1541-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21689372

RESUMO

BACKGROUND: In about 10% of patients with mild hemophilia A, no candidate gene mutations are apparent after complete gene sequencing. AIM OF THE STUDY: To analyze factor VIII gene (F8) mRNA for mutations in five families with mild hemophilia A with no apparent genomic mutation and a reduced response to desmopressin. RESULTS: In four cases, mRNA studies revealed the presence of an abnormal mRNA transcript in addition to normal F8 mRNA. Sequencing of the abnormal transcripts revealed complex abnormalities, which allowed the identification of three different intronic variations (c.2113+1152delA, c.5587-93C>T and c.5999-277G>A) at the DNA level, absent from 387 normal alleles. By in silico analysis, c.2113+1152delA and c.5587-93C>T were strongly predicted to result in the generation of new splice sites with the introduction of premature termination codons, while c.5999-277G>A was predicted to generate a new protein with 30 additional amino acids. However, these predictions were not homogeneous across the different mutations and programs used. The detrimental effect of two mutations was also confirmed by in vitro expression studies. These changes were also identified in related female carriers and in other mild HA patients not included in the original study. No mRNA abnormality was identified in the remaining patient. CONCLUSIONS: Although rare, deep intronic variations may be responsible for mild hemophilia A where no other F8 mutations have been identified and may be associated with a reduced biologic response to desmopressin. F8 mRNA analysis is a useful tool for the identification of deep intronic variation not detectable by standard DNA sequencing.


Assuntos
Coagulação Sanguínea/genética , Fator VIII/genética , Hemofilia A/genética , Íntrons , Mutação , Adulto , Sequência de Bases , Coagulação Sanguínea/efeitos dos fármacos , Estudos de Casos e Controles , Análise Mutacional de DNA , Desamino Arginina Vasopressina/uso terapêutico , Fator VIII/metabolismo , Feminino , Predisposição Genética para Doença , Células HEK293 , Hemofilia A/sangue , Hemofilia A/diagnóstico , Hemofilia A/tratamento farmacológico , Hemostáticos/uso terapêutico , Hereditariedade , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Linhagem , Fenótipo , Sítios de Splice de RNA , RNA Mensageiro/análise , Análise de Sequência de RNA , Índice de Gravidade de Doença , Transfecção , Adulto Jovem
15.
J Thromb Haemost ; 8(12): 2736-42, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20854374

RESUMO

INTRODUCTION: von Willebrand disease (VWD) is an inherited bleeding disorder due to a deficiency or abnormality of von Willebrand factor (VWF), associated with heterogeneous phenotypes. While VWD mutations acting at the protein level have been deeply investigated, fewer data are available on genetic defects affecting VWF mRNA. AIM: The aim of this study was to characterize the molecular mechanism underlying VWD in three patients. METHODS: Mutational screening of the patients (P1-3) was accomplished by DNA sequencing of all VWF exons and splicing junctions. Platelet mRNA was analyzed by reverse-transcription (RT)-PCR and real-time RT-PCR. RESULTS: P1 is a compound heterozygote for a c.1534-3C>A transversion in intron 13 and for a nonsense mutation (p.Q77X) in exon 4. P2 is heterozygous for a splicing mutation in intron 9 (c.1109+2T>C). RT-PCR assays on the patient's platelet RNA revealed three mRNA populations: (i) wild type; (ii) lacking exon 9; and (iii) lacking exons 8 and 9. P3 showed a novel homozygous splicing mutation in intron 46 (c.7770+1G>T), producing three different mRNA species: (i) retaining the first 25 bp of intron 46; (ii) skipping exon 46; and (iii) skipping exon 46 while retaining 5 bp of intron 45. Whenever possible, the effect of mutations on the levels of VWF transcripts was analyzed, showing that mRNA variants containing a premature termination codon are downregulated, probably by the nonsense-mediated mRNA decay pathway. CONCLUSIONS: The identification of the genetic basis of VWD in three patients confirmed that mutations leading to null alleles in the VWF gene are associated with allele-specific mRNA degradation.


Assuntos
Processamento Pós-Transcricional do RNA , RNA Mensageiro/genética , Doenças de von Willebrand/genética , Fator de von Willebrand/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Plaquetas/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação
16.
J Thromb Haemost ; 8(9): 2011-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20586924

RESUMO

BACKGROUND: von Willebrand disease (VWD) type Normandy (VWD 2N) is caused by mutations at the factor (F)VIII-binding site of von Willebrand factor (VWF), located in the D'and D3 domains on the N-terminus of mature VWF. The R854Q mutation is the most frequent cause of this phenotype. OBJECTIVES: We report the characterization of a homozygous VWD 2N mutation, R854W, detected in a patient with a severe VWD phenotype. METHODS: The plasma VWF phenotype was studied, transient expression of recombinant mutant full-length VWF in 293 EBNA cells was performed, and the results were compared with those obtained with wild-type (WT) VWF. Furthermore, expression was also examined in HEK293 cells, which form Weibel-Palade body-like granules when transfected with WT VWF. RESULTS: The multimer analysis of plasma VWF showed the lack of the typical triplet structure, with the presence of the central band only, and a relative decrease in the high molecular mass multimers. Homozygous expression of recombinant R854W VWF resulted in normal amounts of cellular VWF, but with a severe reduction in secretion into the medium. Severe reductions in FVIII binding to R854W VWF, glycoprotein Ib binding activity and collagen binding of secreted W854 VWF was observed, and reproduced the phenotypic parameters of plasma VWF. In HEK293 cells, homozygous R854W VWF failed to form Weibel-Palade body-like granules. CONCLUSIONS: Our results demonstrate that a homozygous R854W mutation in the D' domain of VWF induces impaired secretion and activity of the protein, thereby explaining the severe phenotype of the patient.


Assuntos
Mutação , Doenças de von Willebrand/genética , Fator de von Willebrand/genética , Fator de von Willebrand/metabolismo , Adulto , Coagulação Sanguínea , Linhagem Celular , Análise Mutacional de DNA , Feminino , Heterozigoto , Homozigoto , Humanos , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Fenótipo , Proteínas Recombinantes
17.
J Thromb Haemost ; 7(11): 1824-31, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19719828

RESUMO

BACKGROUND: The relationship of the biologic response to desmopressin with the F8 mutation and physiological characteristics has been poorly investigated in patients with mild hemophilia A. OBJECTIVES: We prospectively assessed the molecular and phenotypic determinants of the biologic response to desmopressin in a cohort of 50 patients with mild hemophilia A. METHODS: Up to 24 h after desmopressin, blood samples were serially obtained and factor (F)VIII and von Willebrand factor (VWF) measured. The promoter region, all exons and exon-intron boundaries of the F8 gene were screened using denaturing high-performance liquid chromatography (DHPLC). Direct sequencing was done when DHPLC screening was normal. Genomic DNA was also sequenced for exons 18-21, 24 and 27 of VWF. RESULTS: Mean basal FVIII:C was 19 +/- 9 IU dL(-1) (range 6-37) and the median postdesmopressin peak increase was 2.5-fold (range 1.1-7.1). Eleven patients with a cross-reacting material positive (CRM(+)) phenotype had similar basal levels and relative increases of FVIII:C to the remaining patients with low FVIII:Ag. Using multivariate regression, FVIII:C half-life was positively related to basal and peak VWF:Ag levels (P = 0.008) and patient age (P = 0.004). Eleven patients had evidence of reduced FVIII survival. While 27 different gene mutations were identified in 41 patients, nine patients had no detectable mutation. These patients had significantly smaller peaks and smaller relative increase of postdesmopressin FVIII:C (median FVIII:C 26 IU dL(-1) vs. 54 IU dL(-1); P < 0.001; fold 1.8 +/- 0.6 vs. 2.9 +/- 0.8; P = 0.002). CONCLUSIONS: In this cohort of patients with mild hemophilia A, a poor biologic response to desmopressin was frequently associated with the absence of detectable F8 mutations.


Assuntos
Desamino Arginina Vasopressina/farmacologia , Fator VIII/efeitos dos fármacos , Fator VIII/genética , Hemofilia A/tratamento farmacológico , Adulto , Idoso , Estudos de Coortes , Desamino Arginina Vasopressina/uso terapêutico , Fator VIII/análise , Componentes do Gene , Humanos , Pessoa de Meia-Idade , Mutação , Fenótipo , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem , Fator de von Willebrand/análise
18.
J Hum Genet ; 53(3): 275-284, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18217193

RESUMO

To provide a National database, 1,410 unrelated hemophilia A (HA) patients were investigated using screening methods denaturing high-performance liquid chromatography (DHPLC), conformational-sensitive gel electrophoresis (CSGE)] and/or direct sequencing. F8 gene mutations were identified in 877 (81%), 146 (82%), and 133 (89%) families with severe, moderate, or mild HA, respectively. Among the 382 different mutations detected, 217 (57%) have not previously been reported in the F8 Haemophilia A Mutation, Structure, Test and Resource Site (HAMSTeRS) database. Mutations leading to a null allele accounted for 82, 15%, and less than 1% of severe, moderate, or mild HA, respectively. A missense mutation was identified in 16%, 68%, and 81% of severe, moderate, or mild HA, respectively. They included 105 missense mutations (48%), 41 small deletions (19%), 25 splice site mutations (12%), 24 nonsense mutations (11%), 18 insertions (8%), three large deletions (1%), and one deletion plus insertion. Unreported mutations were distributed throughout the F8 gene, as they affected all F8 exons but exon 20. We report a wide spectrum of mutations collected in a large National database. The type of mutation was a strong predictor of the clinical phenotype. This database is expected to considerably improve the genetic counseling and medical care of HA families in Italy.


Assuntos
Fator VIII/genética , Hemofilia A/genética , Mutação , Processamento Alternativo , Cromatografia Líquida de Alta Pressão , Éxons , Fator VIII/química , Hemofilia A/sangue , Itália , Mutação de Sentido Incorreto , Conformação Proteica , Deleção de Sequência
19.
Haemophilia ; 13(3): 311-6, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17498081

RESUMO

Genetic analysis was carried out in 37 Albanian patients with haemophilia A. The factor VIII intron 22 inversion was detected only in 2/19 (10.5%) apparently unrelated patients with severe haemophilia A, while the intron 1 inversion was absent. A total of 19 different gene mutations were identified. Ten mutations were novel: four null mutations in severe haemophilia A patients (Gln1090X, Cys1832X, 2374delT, 5676insT) and six missense mutations (five in severe haemophilia A) (Ile76Thr, Leu299Pro, Asp525Glu, Cys692Tyr, His1755Leu and Trp1835Cys). None of these novel mutations occurred at CpG hotspots. These results further emphasize the extreme heterogeneity of the molecular basis of haemophilia A. The low prevalence of intron 22 inversion in Albanian patients with severe haemophilia A should be addressed by further studies.


Assuntos
Análise Mutacional de DNA/métodos , Fator VIII/genética , Hemofilia A/genética , Mutação , Albânia , Feminino , Humanos , Masculino
20.
Biochem Mol Biol Int ; 42(6): 1199-213, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9305538

RESUMO

A biological factor that inhibited prolactin secretion by pituitary cells cultured in vitro was identified, purified, and partially characterized from normal rabbit serum. This biological factor was also found to potentiate dopamine-mediated aortic contraction using rabbit aortic strips in vitro. Following SDS-PAGE, this factor displayed an apparent Mr of 17 kDa, which is different from the Mr of most known endogenous factors having an inhibiting activity on pituitary prolactin secretion, suggesting that this may be a yet-to-be identified novel molecule.


Assuntos
Fatores Biológicos/sangue , Fatores Biológicos/farmacologia , Hipófise/metabolismo , Prolactina/metabolismo , Animais , Aorta/efeitos dos fármacos , Fatores Biológicos/isolamento & purificação , Células Cultivadas , Cromatografia Líquida de Alta Pressão/métodos , Dopamina/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Contração Muscular/efeitos dos fármacos , Hipófise/citologia , Hipófise/efeitos dos fármacos , Coelhos , Ratos , Ratos Wistar , Análise de Sequência
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