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1.
Haemophilia ; 23(6): e488-e496, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28960694

RESUMO

INTRODUCTION: Factor XI (FXI) deficiency is a rare disorder with molecular heterogeneity in Caucasians but relatively frequent and molecularly homogeneous in certain populations. AIM: To characterize FXI deficiency in a Spanish town of 60 000 inhabitants. METHODS: A total of 324 764 APTT tests were screened during 20 years. FXI was evaluated by FXI:C and by Western blot. Genetic analysis of F11 was performed by sequencing, multiplex ligation-dependent probe amplification and genotyping. RESULTS: Our study identified 46 unrelated cases and 170 relatives with FXI deficiency carrying 12 different genetic defects. p.Cys56Arg, described as founder mutation in the French-Basque population, was identified in 109 subjects from 24 unrelated families. This mutation was also identified in 2% of the general population. p.Cys416Tyr, c.1693G>A and p.Pro538Leu were identified in 7, 6 and 2 unrelated families, respectively. NGS analysis of the whole F11 gene revealed a common haplotype for each of the four recurrent mutations, suggesting a founder effect. The analysis of plasma FXI of four p.Pro538Leu homozygous carriers revealed that this variant was not activated by FXIIa. We identified four mutations previously described in other Caucasian subjects with FXI deficiency (p.Lys536Asn; p.Thr322Ile, p.Arg268Cys and c.325G>A) and four new gene defects: p.(Cys599Tyr) potentially causing a functional deficiency, p.(Ile426Thr), p.(Ile592Thr) and the first worldwide duplication of 1653 bp involving exons 8 and 9. Bleeding was rare and mild. CONCLUSIONS: Our population-cohort study supplies new evidences that FXI deficiency in Caucasians is more common than previously thought and confirmed the wide underlying genetic heterogeneity, caused by both recurrent and sporadic mutations.


Assuntos
Deficiência do Fator XI/genética , Fator XI/genética , Duplicação Gênica , Mutação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Deficiência do Fator XI/sangue , Deficiência do Fator XI/epidemiologia , Feminino , Frequência do Gene , Genótipo , Haplótipos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Linhagem , Análise de Sequência de DNA , Espanha/epidemiologia
2.
Genes Immun ; 16(2): 134-41, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25569262

RESUMO

HIV-1 induces activation of complement through the classical and lectin pathways. However, the virus incorporates several membrane-bound or soluble regulators of complement activation (RCA) that inactivate complement. HIV-1 can also use the complement receptors (CRs) for complement-mediated antibody-dependent enhancement of infection (C-ADE). We hypothesize that hypofunctional polymorphisms in RCA or CRs may protect from HIV-1 infection. For this purpose, 139 SNPs located in 19 RCA and CRs genes were genotyped in a population of 201 Spanish HIV-1-exposed seronegative individuals (HESN) and 250 HIV-1-infected patients. Two SNPs were associated with infection susceptibility, rs1567190 in CR2 (odds ratio (OR) = 2.27, P = 1 × 10(-4)) and rs2842704 in C4BPA (OR = 2.11, P = 2 × 10(-4)). To replicate this finding, we analyzed a cohort of Italian, sexually HESN individuals. Although not significant (P = 0.25, OR = 1.57), similar genotypic proportions were obtained for the CR2 marker rs1567190. The results of the two association analyses were combined through a random effect meta-analysis, with a significant P-value of 2.6 x 10(-5) (OR = 2.07). Furthermore, we found that the protective CR2 genotype is correlated with lower levels CR2 mRNA as well as differences in the ratio of the long and short CR2 isoforms.


Assuntos
Infecções por HIV/genética , Infecções por HIV/imunologia , HIV-1/imunologia , Receptores de Complemento 3d/genética , Receptores de Complemento 3d/imunologia , Estudos de Coortes , Suscetibilidade a Doenças/imunologia , Anticorpos Anti-HIV/genética , Haplótipos , Humanos , Imunidade Inata/genética , Masculino , Polimorfismo de Nucleotídeo Único
5.
IEEE Trans Nanobioscience ; 7(2): 133-41, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18556261

RESUMO

In this work, parametric information-theory measures for the characterization of binding sites in DNA are extended with the use of transitional probabilities on the sequence. We propose the use of parametric uncertainty measures such as Rényi entropies obtained from the transition probabilities for the study of the binding sites, in addition to nucleotide frequency-based Rényi measures. Results are reported in this work comparing transition frequencies (i.e., dinucleotides) and base frequencies for Shannon and parametric Rényi entropies for a number of binding sites found in E. Coli, lambda and T7 organisms. We observe that the information provided by both approaches is not redundant. Furthermore, under the presence of noise in the binding site matrix we observe overall improved robustness of nucleotide transition-based algorithms when compared with nucleotide frequency-based method.


Assuntos
DNA/química , DNA/ultraestrutura , Modelos Químicos , Modelos Moleculares , Nucleotídeos/química , Sítios de Ligação , Simulação por Computador , Entropia
6.
J Biomed Mater Res A ; 83(2): 463-70, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17477391

RESUMO

A series of polymeric biomaterials including poly (methyl acrylate) (PMA), chitosan (CHT), poly(ethyl acrylate) (PEA), poly(hydroxyethyl acrylate) (PHEA), and a series of random copolymers containing ethyl acrylate and hydroxyethyl acrylate monomeric units were tested in vitro as culture substrates and compared for their impact on the proliferation and expansion of Schwann cells (SCs). Immunocytochemical staining assay and scanning electron microscopy techniques were applied to perform a quantitative analysis to determine the correct maintenance of the cultured glial cells on the different biomaterials. The results strongly suggest that cell attachment and proliferation is influenced by the substrate's surface chemistry, and that hydrophobic biomaterials based on PMA, PEA, and the copolymers PEA and PHEA in a narrow composition window are suitable substrates to promote cell attachment and proliferation of SCs in vitro.


Assuntos
Células de Schwann/citologia , Animais , Adesão Celular , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Ratos , Ratos Wistar , Células de Schwann/ultraestrutura , Especificidade por Substrato , Tensão Superficial , Água/metabolismo
7.
J Thromb Haemost ; 4(7): 1537-45, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16839351

RESUMO

BACKGROUND: High-normal and elevated plasma FIX activity (FIX:C) levels are associated with increased risk for venous- and possibly arterial-thrombosis. OBJECTIVE: Because the broad normal range for FIX:C involves a substantial unknown genetic component, we sought to identify quantitative-trait loci (QTLs) for this medically important hemostasis trait. METHODS: We performed a genome-wide screen and a resequencing-based variation scan of the known functional regions of every distinct FIX gene (F9) in the genetic analysis of idiopathic thrombophilia project (GAIT), a collection of 398 Spanish-Caucasians from 21 pedigrees. RESULTS: We found no evidence for linkage (LOD scores <1.5) despite genotyping more than 540 uniformly-spaced microsatellites. We identified 27 candidate F9 polymorphisms, including three in cis-elements responsible for the increase in FIX:C that occurs with aging, but found no significant genotype-specific differences in mean FIX:C levels (P-values > or = 0.11) despite evaluating every polymorphism in GAIT by marginal multicovariate measured-genotype association analysis. CONCLUSIONS: The heritable component of interindividual FIX:C variability likely involves a collection of QTLs with modest effects that may reside in genes other than F9. Nevertheless, because the alleles of these 27 polymorphisms exhibited a low overall degree of linkage disequilibrium, we are currently defining their haplotypes to interrogate several highly-conserved non-exonic sequences and other F9 segments not examined here.


Assuntos
Fator IX/genética , Polimorfismo Genético , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Fator IX/análise , Feminino , Ligação Genética , Genômica/métodos , Genótipo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Linhagem , Locos de Características Quantitativas , Trombofilia/genética
8.
Arterioscler Thromb Vasc Biol ; 25(7): 1489-92, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15845911

RESUMO

OBJECTIVE: Levels of tissue factor pathway inhibitor (TFPI) have been associated with arteriosclerosis and thrombotic disease. Although a genetic component to variation in TFPI levels is well-documented, no systematic genome-wide screens have been conducted to localize genes influencing levels of TFPI. METHODS AND RESULTS: We studied TFPI levels in 397 individuals in 21 Spanish families participating in the Genetic Analysis of Idiopathic Thrombosis (GAIT) study. Twelve families were selected through a proband with idiopathic thrombosis and 9 were ascertained without regard to phenotype. A genome scan was performed using microsatellite markers spaced at approximately 10 cM intervals. Standard multipoint variance component linkage methods were used. The heritability of TFPI levels was 0.52 (P<0.0001), with no evidence for shared household effects. In the genome screen, only 1 LOD score >2 was observed. On chromosome 2q, the maximum multipoint LOD score was 3.52 near marker D2S1384. This is near the structural gene for TFPI, which is located at 2q32. In follow-up association analyses, marginal evidence of association (P=0.04) was observed with the TFPI promoter variant C-399T. CONCLUSIONS: These results suggest that polymorphisms in and around the TFPI structural gene may be the major genetic determinants of variation in TFPI levels.


Assuntos
Cromossomos Humanos Par 2 , Lipoproteínas/sangue , Lipoproteínas/genética , Trombose/sangue , Trombose/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Genômica , Humanos , Lactente , Escore Lod , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
9.
Appl Health Econ Health Policy ; 13(2): 233-42, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25652150

RESUMO

BACKGROUND: Patients with venous thromboembolism (VTE) commonly have an underlying genetic predisposition. However, genetic tests nowadays in use have very low sensitivity for identifying subjects at risk of VTE. Thrombo inCode(®) is a new genetic tool that has demonstrated very good sensitivity, thanks to very good coverage of the genetic variants that modify the function of the coagulation pathway. OBJECTIVE: To conduct an economic analysis of risk assessment of VTE from the perspective of the Spanish National Health System with Thrombo inCode(®) (a clinical-genetic function for assessing the risk of VTE) versus the conventional/standard method used to date (factor V Leiden and prothrombin G20210A). METHODS: An economic model was created from the National Health System perspective, using a decision tree in patients aged 45 years with a life expectancy of 81 years. The predictive capacity of VTE, based on identification of thrombophilia using Thrombo inCode(®) and using the standard method, was obtained from two case-control studies conducted in two different populations (S. PAU and MARTHA; 1,451 patients in all). Although this is not always the case, patients who were identified as suffering from thrombophilia were subject to preventive treatment of VTE with warfarin, leading to a reduction in the number of VTE events and an increased risk of severe bleeding. The health state utilities (quality-adjusted life-years [QALYs]) and costs (in 2013 EUR values) were obtained from the literature and Spanish sources. RESULTS: On the basis of a price of EUR 180 for Thrombo inCode(®), this would be the dominant option (more effective and with lower costs than the standard method) in both populations. The Monte Carlo probabilistic analyses indicate that the dominance would occur in 100 % of the simulations in both populations. The threshold price of Thrombo inCode(®) needed to reach the incremental cost-effectiveness ratio (ICER) generally accepted in Spain (EUR 30,000 per QALY gained) would be between EUR 3,950 (in the MARTHA population) and EUR 11,993 (in the S. PAU population). CONCLUSION: According to the economic model, Thrombo inCode(®) is the dominant option in assessing the risk of VTE, compared with the standard method currently used.


Assuntos
Análise Custo-Benefício , Predisposição Genética para Doença , Testes Genéticos/economia , Medição de Risco/economia , Tromboembolia Venosa/economia , Tromboembolia Venosa/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Árvores de Decisões , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Econômicos , Valor Preditivo dos Testes , Medição de Risco/métodos , Sensibilidade e Especificidade , Espanha , Tromboembolia Venosa/etiologia
10.
J Thromb Haemost ; 13(10): 1867-77, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26286125

RESUMO

BACKGROUND: The relationships of thrombin generation (TG) with cardiovascular disease risk are underevaluated in population-based cohorts. OBJECTIVES: To evaluate the relationships of TG influenced by the contact and tissue factor coagulation pathways ex vivo with common single-nucleotide polymorphisms (SNPs) and incident cardiovascular disease and stroke. PATIENTS/METHODS: We measured peak TG (pTG) in baseline plasma samples of Cardiovascular Health Study participants (n = 5411), both with and without inhibitory anti-factor XIa antibody (pTG/FXIa(-) ). We evaluated their associations with ~ 50 000 SNPs by using the IBCv2 genotyping array, and with incident cardiovascular disease and stroke events over a median follow-up of 13.2 years. RESULTS: The minor allele for an SNP in the FXII gene (F12), rs1801020, was associated with lower pTG in European-Americans (ß = - 34.2 ± 3.5 nm; P = 3.3 × 10(-22) ; minor allele frequency [MAF] = 0.23) and African-Americans (ß = - 31.1 ± 7.9 nm; P = 9.0 × 10(-5) ; MAF = 0.42). Lower FXIa-independent pTG (pTG/FXIa(-) ) was associated with the F12 rs1801020 minor allele, and higher pTG/FXIa(-) was associated with the ABO SNP rs657152 minor allele (ß = 16.3 nm; P = 4.3 × 10(-9) ; MAF = 0.37). The risk factor-adjusted ischemic stroke hazard ratios were 1.09 (95% confidence interval CI 1.01-1.17; P = 0.03) for pTG, 1.06 (95% CI 0.98-1.15; P = 0.17) for pTG/FXIa(-) , and 1.11 (95% CI 1.02-1.21; P = 0.02) for FXIa-dependent pTG (pTG/FXIa(+) ), per one standard deviation increment (n = 834 ischemic strokes). In a multicohort candidate gene analysis, rs1801020 was not associated with incident ischemic stroke (ß = - 0.02; standard error = 0.08; P = 0.81). CONCLUSIONS: These results support the importance of contact activation pathway-dependent TG as a risk factor for ischemic stroke, and indicate the importance of F12 SNPs for TG ex vivo and in vivo.


Assuntos
Coagulação Sanguínea/genética , Isquemia Encefálica/genética , Fator XII/genética , Acidente Vascular Cerebral/genética , Trombina/metabolismo , Negro ou Afro-Americano/genética , Fatores Etários , Idoso , Isquemia Encefálica/sangue , Isquemia Encefálica/etnologia , Fator XII/metabolismo , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Incidência , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/etnologia , Fatores de Tempo , Estados Unidos/epidemiologia , População Branca/genética
11.
J Comp Neurol ; 397(4): 493-518, 1998 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-9699912

RESUMO

Two major classes of early-born neurons are distinguished during early corticogenesis in the rat. The first class is formed by the cortical pioneer neurons, which are born in the ventricular neuroepithelium all over the cortical primordium. They appear at embryonic day (E) 11.5 in the lateral aspect of the telencephalic vesicle and cover its whole surface on E12. These cells, which show intense immunoreactivity for calbindin and calretinin, are characterized by their large size and axonal projection. They remain in the marginal zone after the formation of the cortical plate; they project first into the ventricular zone, and then into the subplate and the internal capsule. Therefore, these cells are the origin of the earliest efferent pathway of the developing cortex. Pioneer neurons are only present in prenatal brains. The second class is formed by subpial granule neurons, which form the subpial granular layer (SGL), previously considered to be found exclusively in the human cortex. SGL neurons are smaller than pioneer neurons. They are generated in a transient compartment of the retrobulbar ventricle between E12 and E14, and we propose the hypothesis that they invade the marginal zone, through tangential subpial migration, at different moments of fetal life. SGL neurons contain calbindin, calretinin, and gamma-aminobutyric acid (GABA), but the GABA-immunoreactive group becomes inconspicuous before birth. The extracellular matrix-like glycoprotein reelin, a molecule crucial for cortical lamination, is prenatally expressed by SGL neurons; postnatally, it is present in both Cajal-Retzius cells and subpial pyriform cells, both derivatives of SGL cells. In the rat, Cajal-Retzius cells are horizontal neurons that remain only until the end of the first postnatal week. They are located in layer I at a critical distance of approximately 20 microm from the pial surface and express reelin and, only occasionally, calretinin. Subpial pyriform cells coexpress reelin and calretinin and remain in layer I longer than Cajal-Retzius cells. Both pioneer neurons and subpial granule neurons are specific to the cortex. They mark the limit between the rudimentary cerebral cortex and olfactory bulb in the rat during early corticogenesis.


Assuntos
Animais Recém-Nascidos/anatomia & histologia , Córtex Cerebral/citologia , Córtex Cerebral/embriologia , Feto/citologia , Neurônios/fisiologia , Ratos/anatomia & histologia , Ratos/embriologia , Envelhecimento/fisiologia , Animais , Linhagem Celular , Senescência Celular/fisiologia , Pia-Máter/citologia , Pia-Máter/embriologia , Ratos Wistar , Proteína Reelina
12.
Thromb Haemost ; 74(5): 1215-20, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8607097

RESUMO

We report the genetic abnormalities in the protein C genes of a Spanish child with neonatal purpura fulminans and disseminated intravascular coagulation, associated with undetectable protein C levels. Direct sequencing of the nine protein C gene exons and their splice junctions indicated that the proband is a compound heterozygote with two mutant protein C gene alleles, Y124C and Q132X, that do not express protein C in plasma. The Y124C mutation was inherited from the mother and is due to a novel A to G transition at nucleotide 3416, which results in the substitution of cysteine for tyrosine 124, a highly conserved amino acid in EGF-like domains. The paternal inherited mutation (Q132X) is a C to T transition at nucleotide 3439, which replaces glutamine 132 with a Stop codon signal. This mutation, if expressed, should result in the synthesis of a truncated protein of 131 amino acids. Y124C or Q132X are present in the heterozygous state in the asymptomatic parents and siblings of the proband, all of which have half the normal plasma levels of protein C. Q123X has also been identified in families where type I PC deficiency is inherited as a clinically dominant trait. Therefore, the presence of the same mutation in a family showing a clinically recessive pattern of inheritance indicates that other factors, apart from the type of protein C gene mutation, are responsible for the clinical expression of protein C deficiency.


Assuntos
Proteína C/genética , Púrpura/genética , Alelos , Sequência de Bases , Criança , Heterozigoto , Humanos , Masculino , Dados de Sequência Molecular , Mutação , Polimorfismo Genético , Deficiência de Proteína C , Púrpura/metabolismo , Análise de Sequência , Espanha
13.
Thromb Haemost ; 72(1): 65-9, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7974377

RESUMO

Single strand conformation polymorphism (SSCP) analysis of exon 7 of the protein C gene has identified a novel splice site missense mutation (184, Q-->H), in a newborn child with purpura fulminans and undetectable protein C levels. The mutations, seen in the homozygous state in the child and in the heterozygous state in her mother, was characterized and found to be a G to C nucleotide substitution at the -1 position of the donor splice site of intron 7 of the protein C gene, which changes histidine 184 for glutamine (184, Q-->H). According to analysis of the normal and mutated sequences, this mutation should also abolish the function of the donor splice site of intron 7 of the protein C gene. Since such a mutation is compatible with the absence of gene product in plasma and since DNA sequencing of all protein C gene exons in this patient did not reveal any other mutation, we postulate that mutation 184, Q-->H results in the absence of protein C gene product in plasma, which could be the cause of the severe phenotype observed in this patient.


Assuntos
DNA Recombinante , Éxons , Homozigoto , Vasculite por IgA/genética , Deficiência de Proteína C , Sequência de Bases , Testes de Coagulação Sanguínea , Feminino , Humanos , Recém-Nascido , Dados de Sequência Molecular , Mutação , Proteína C/genética
14.
Thromb Haemost ; 75(6): 870-6, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8822578

RESUMO

Nonsense mutations, deletions and splice site mutations are a common cause of type I protein C deficiency. Either directly or indirectly by altering the reading frame, these lesions generate or may generate premature stop codons and could therefore be expected to result in premature termination of translation. In this study, the possibility that such mutations could instead exert their pathological effects at an earlier stage in the expression pathway, through "allelic exclusion" at the RNA level, was investigated. Protein C (PROC) mRNA was analysed in seven Spanish type I protein C deficient patients heterozygous for two nonsense mutations, a 7bp deletion, a 2bp insertion and three splice site mutations. Ectopic RNA transcripts from patient and control lymphocytes were analysed by RT-PCR and direct sequencing of amplified PROC cDNA fragments. The nonsense mutations and the deletion were absent from the cDNAs indicating that only mRNA derived from the normal allele had been expressed. Similarly for the splice site mutations, only normal PROC cDNAs were obtained. In one case, exclusion of the mutated allele could be confirmed by polymorphism analysis. In contrast to these six mutations, the 2 bp insertion was not associated with loss of mRNA from the mutated allele. In this case, cDNA analysis revealed the absence of 19 bases from the PROC mRNA consistent with the generation and utilization of a cryptic splice site 3' to the site of mutation, which would result in a frameshift and a premature stop codon. It is concluded that allelic exclusion is a common causative mechanism in those cases of type I protein C deficiency which result from mutations that introduce premature stop codons.


Assuntos
Transtornos das Proteínas Sanguíneas/genética , Deficiência de Proteína C , RNA Mensageiro/genética , Alelos , DNA Complementar/análise , DNA Complementar/genética , Feminino , Mutação da Fase de Leitura , Humanos , Masculino , Linhagem , Proteína C/genética , RNA Mensageiro/análise , Espanha , Transcrição Gênica
15.
Blood Coagul Fibrinolysis ; 7(1): 15-23, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8845458

RESUMO

We report the results of protein C gene (PROC) analysis in a Spanish family with hereditary PC deficiency characterized by the presence of three siblings with PC anticoagulant activity levels clearly below 50% of normal and PC antigen and amidolytic activities between 50 and 75% of normal. Their parents are first cousins and have PC levels between 50 and 80% of normal. Sequence analysis of the whole coding sequence of the PROC gene revealed that the three siblings are double homozygotes for a G to A transition at nucleotide 3203 that replaces arginine 87 by histidine (R87H) and for another G to A transition at nucleotide 7054, in intron 7 (7054G --> A). Both parents and one sister were found to be double heterozygotes for these two mutations. Screening for the intronic mutation in a control group and RT-PCR cDNA studies from ectopically transcribed mRNA indicated that 7054G --> A is most likely a rare but neutral DNA variant. These results and the fact that heterozygosity for the missense R87H mutation has also been found associated with a slightly decreased PC anticoagulant activity in another Spanish family, lead us to conclude that homozygosity for R87H is responsible for the PC deficient phenotype in these three siblings.


Assuntos
DNA/genética , Variação Genética , Heterozigoto , Homozigoto , Íntrons , Proteína C/genética , Adenina/química , Adulto , Sequência de Aminoácidos , Sequência de Bases , Éxons , Guanina/química , Humanos , Masculino , Dados de Sequência Molecular , Mutação , Linhagem , Deficiência de Proteína C
16.
Blood Coagul Fibrinolysis ; 6(3): 198-206, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7654933

RESUMO

Congenital dysfibrinogenaemia was found in three non-related patients. None of them had a haemorrhagic tendency, but one gave a thrombotic history. When their fibrinogens were treated with thrombin, they released fibrinopeptides A and B at normal rates, but the resultant fibrin monomers produced exhibited abnormal polymerization curves. This abnormality was more marked in fibrinogen Villajoyosa than in Barcelonas III and IV. Plasminogen and t-PA binding to fibrin monomers from the three dysfibrinogenaemias was similar to that of normal fibrin monomers. The gamma chain was purified from the three fibrinogens, treated with CNBr and the peptides produced were separated by reversed-phase HPLC. Chromatograms of digested fibrinogens showed an abnormal peak that was not present in the normal gamma chain. Amino acid sequence analysis of abnormal peptides and genomic DNA sequencing revealed that the gamma arginine 275 had been changed in the three fibrinogens; in two cases it was substituted by histidine, and in the third by cysteine. The altered properties observed in fibrin monomers produced from fibrinogen with the gamma Arg 275-->His or gamma Arg 275-->Cys substitution, suggests that this amino acid is important in maintaining the protein structure necessary for normal polymerization, but is not essential for the binding of t-PA or plasminogen to fibrin. It also suggests that the change Arg-->Cys produces more severe alterations in the functions of fibrinogen than the substitution Arg-->His.


Assuntos
Afibrinogenemia/genética , Fibrinogênios Anormais/genética , Plasminogênio/metabolismo , Ativador de Plasminogênio Tecidual/metabolismo , Adulto , Afibrinogenemia/sangue , Idoso , Sequência de Aminoácidos , Sequência de Bases , Biopolímeros , Testes de Coagulação Sanguínea , Feminino , Fibrinogênios Anormais/metabolismo , Humanos , Masculino , Dados de Sequência Molecular , Mapeamento de Peptídeos , Reação em Cadeia da Polimerase , Ligação Proteica , Trombina/farmacologia , Trombose/genética
17.
Blood Coagul Fibrinolysis ; 7(6): 625-31, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8899152

RESUMO

RNA-based studies are an important tool for the identification and functional characterization of mutations underlying inherited disease. These studies could in principle be compromised by 'aberrant splicing' (the generation of alternatively spliced transcripts lacking any obvious function) during normal expression of the genes under investigation. Using a highly sensitive RT-PCR assay, we show here that aberrant splicing is a frequent occurrence during expression of the protein C (PROC) and protein S (PROS) genes. Aberrantly spliced transcripts were present in different cell types including liver, the main expressing tissue for both protein C and protein S. In an attempt to compare individual mRNA splicing patterns, PROC and PROS RNA from easily accessible cells of different healthy control individuals was studied. However, variation between different RT-PCR assays from the same individual precluded both the relative quantitation of the aberrant transcripts and the analysis of interindividual differences. Our findings are consistent with the notion that a low level of aberrantly spliced transcripts are routinely generated during PROC and PROS gene expression. The possibility that these transcripts may complicate the RT-PCR analysis of pathological transcripts must be taken into account when RNA-based strategies of disease analysis are considered.


Assuntos
Proteína C/genética , Proteína S/genética , Splicing de RNA , Eletroforese em Gel de Ágar , Éxons , Humanos , Reação em Cadeia da Polimerase , Transcrição Gênica
18.
Med Clin (Barc) ; 99(17): 649-52, 1992 Nov 21.
Artigo em Espanhol | MEDLINE | ID: mdl-1280311

RESUMO

BACKGROUND: In order to find alternatives for the diagnosis of hereditary protein C (PC) deficiency, we have studied the diagnostic informativity of the restriction fragment length polymorphism (RFLP) MI, located 7 kb upstream of the PC gene and detected with the restriction enzyme MspI. METHODS: The RFLP MI has been analysed in 77 individuals belonging to 27 families with congenital PC deficiency, as well as in a control group of 46 healthy donors. The analysis has been performed by PCR amplification and MspI digestion of the polymorphic DNA fragment. RESULTS: The allelic frequencies of the RFLP MI in the population studied are 0.69 for the allele A1, without the MspI restriction site, and 0.31 for the allele A2, with the MspI site. No differences have been found between the control and the PC deficient groups. The informativity of the polymorphism has been calculated to be 33.8%. Consegregation studies between this RFLP and PC deficiency have allowed the determination of the allele associated to the polymorphism in 21 out of the 27 studied families. Furthermore, an asymptomatic PC deficient carrier, with normal PC levels, has been identified. CONCLUSIONS: The study of this RFLP in families with hereditary PC deficiency may be useful for the identification of PC deficient carriers as well as for the prenatal diagnosis of the deficiency.


Assuntos
Transtornos da Coagulação Sanguínea/congênito , Desoxirribonucleases de Sítio Específico do Tipo II/química , Deficiência de Proteína C , Alelos , Transtornos da Coagulação Sanguínea/enzimologia , Transtornos da Coagulação Sanguínea/genética , Portador Sadio/diagnóstico , DNA , Desoxirribonuclease HpaII , Feminino , Humanos , Polimorfismo Genético , Gravidez , Diagnóstico Pré-Natal
19.
J Thromb Haemost ; 11(3): 521-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23279374

RESUMO

BACKGROUND: ß2 -Glycoprotein I (ß2 -GPI), also designated apolipoprotein H, is a 50-kDa protein that circulates in blood at high concentrations, playing important roles in autoimmune diseases, hemostasis, atherogenesis, and angiogenesis, as well as in host defense against bacteria and in protein/cellular waste removal. Plasma ß2 -GPI levels have a significant genetic component (heritability of ~ 80%). OBJECTIVES: To present the results of a genome-wide association study for plasma ß2 -GPI levels in a set of extended pedigrees from the Genetic Analysis of Idiopathic Thrombophilia (GAIT) Project. PATIENTS/METHODS: A total of 306 individuals for whom ß2 -GPI plasma measurements were available were typed for 307,984 single-nucleotide polymorphisms (SNPs) with the Infinium 317k Beadchip (Illumina). Association with the ß2 -GPI phenotype was investigated through variance component analysis, and the most significant results were followed up for association with coronary artery disease (CAD) in an independent in silico analysis involving 5765 CAD cases from the PROCARDIS Project and 7264 controls from the PROCARDIS Project and the Wellcome Trust Case Control Consortium (WTCCC) collection. RESULTS: After correction for multiple testing, three SNPs located in/around two genes (ELF5 and SCUBE2) reached genome-wide significance. Moreover, an SNP in the APOH gene showed suggestive association with the ß2 -GPI phenotype. Some of the identified genes are plausible biological candidates, as they are actually or potentially involved in inflammatory processes. CONCLUSIONS: Our results represent a first step towards identifying common variants reflecting the genetic architecture influencing plasma ß2 -GPI levels, and warrant further validation by functional experiments, as the functions of some of the discovered loci are still unknown.


Assuntos
Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/genética , Polimorfismo de Nucleotídeo Único , beta 2-Glicoproteína I/sangue , beta 2-Glicoproteína I/genética , Proteínas Adaptadoras de Transdução de Sinal , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Autoimunes/sangue , Doenças Autoimunes/genética , Proteínas de Ligação ao Cálcio , Estudos de Casos e Controles , Criança , Pré-Escolar , Proteínas de Ligação a DNA , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Lactente , Modelos Lineares , Modelos Logísticos , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Linhagem , Fenótipo , Proteínas Proto-Oncogênicas c-ets/genética , Espanha , Trombofilia/sangue , Trombofilia/genética , Fatores de Transcrição , Adulto Jovem
20.
Neuroscience ; 224: 102-15, 2012 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-22917609

RESUMO

After trauma brain injury, a large number of cells die, releasing neurotoxic chemicals into the extracellular medium, decreasing cellular glutathione levels and increasing reactive oxygen species that affect cell survival and provoke an enlargement of the initial lesion. Alpha-lipoic acid is a potent antioxidant commonly used as a treatment of many degenerative diseases such as multiple sclerosis or diabetic neuropathy. Herein, the antioxidant effects of lipoic acid treatment after brain cryo-injury in rat have been studied, as well as cell survival, proliferation in the injured area, gliogenesis and angiogenesis. Thus, it is shown that newborn cells, mostly corresponded with blood vessels and glial cells, colonized the damaged area 15 days after the lesion. However, lipoic acid was able to stimulate the synthesis of glutathione, decrease cell death, promote angiogenesis and decrease the glial scar formation. All those facts allow the formation of new neural tissue. In view of the results herein, lipoic acid might be a plausible pharmacological treatment after brain injury, acting as a neuroprotective agent of the neural tissue, promoting angiogenesis and reducing the glial scar formation. These findings open new possibilities for restorative strategies after brain injury, stroke or related disorders.


Assuntos
Lesões Encefálicas/patologia , Neovascularização Fisiológica/efeitos dos fármacos , Neuroglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Ácido Tióctico/farmacologia , Animais , Antioxidantes/farmacologia , Western Blotting , Cromatografia Líquida de Alta Pressão , Cicatriz/patologia , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Microscopia Eletrônica de Transmissão , Neuroglia/ultraestrutura , Ratos , Ratos Wistar
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