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1.
Orthod Craniofac Res ; 21(2): 104-111, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29537699

RESUMO

OBJECTIVE: To evaluate the stability of anterior open bite (AOB) treatment with bonded spurs associated with high-pull chincup (BS/HPCC). METHODS: The experimental group consisted of 25 Class I AOB patients (15 female, 10 male) treated with BS/HPCC for 1 year. Cephalograms were analysed at pre-treatment (T1), post-treatment (T2) and at the 3-year post-treatment (T3) stage with the patients mean ages of 8.10, 9.14 and 12.18 years, respectively. The control group consisted of 23 subjects (13 female, 10 male) with normal occlusion, with comparable ages at the 3 stages (8.45, 9.45 and 12.50 years at T1, T2 and T3, respectively). T tests were used for intergroup comparisons at T1 and to compare the changes during the 3-year post-treatment period (T2-T3). Intragroup comparison in the treated group was evaluated with dependent t tests between T1 and T2. Correlations between the overbite changes in the T2-T3 period, the pre-treatment AOB severity and the amount of correction achieved during treatment were evaluated with Pearson's correlation coefficient. RESULTS: No statistically significant relapse of the AOB was found at T3. Only 1 patient had a clinically significant AOB relapse. Neither the pre-treatment AOB severity nor the amount of correction was related to overbite changes during the 3-year post-treatment period. CONCLUSIONS: There was no statistically significant relapse of the AOB, and the clinical stability of AOB correction 3-year post-treatment was of 96%.


Assuntos
Aparelhos de Tração Extrabucal , Mordida Aberta/terapia , Aparelhos Ortodônticos , Cefalometria , Criança , Feminino , Humanos , Masculino , Mordida Aberta/diagnóstico por imagem , Dimensão Vertical
2.
Protein Expr Purif ; 131: 60-69, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27856402

RESUMO

Visceral Leishmaniasis (VL) represents an important global health problem in several warm countries around the world. The main targets in this study are the two nucleoside triphosphate diphosphohydrolases (NTPDases) from Leishmania infantum chagasi that are the main etiologic agent of VL in the New World. These enzymes, called LicNTPDase1 and -2, are homologous to members 5 and 6 of the mammalian E-NTPDase/CD39 superfamily of enzymes. These enzymes hydrolyze nucleotides and accordingly can participate in the purine salvage pathways and in the modulation of purinergic signaling through the extracellular nucleotide-dependent host immune responses. They can therefore affect adhesion and infection of host cells and the parasite virulence. To further characterize these enzymes, in this work, we expressed LicNTPDase1 and -2 in the classical bacterial system Escherichia coli and mammalian cell system COS-7 cells. Our data demonstrate that changes in refolding after expression in bacteria can increase the activity of recombinant (r) rLicNTPDase2 up to 20 times but has no significant effect on rLicNTPDase1. Meanwhile, the expression in COS-7 led to a significant increase in activity for rLicNTPDase1.


Assuntos
Adenosina Trifosfatases , Antígenos CD , Apirase , Expressão Gênica , Leishmania infantum/genética , Redobramento de Proteína , Proteínas de Protozoários , Adenosina Trifosfatases/biossíntese , Adenosina Trifosfatases/química , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/isolamento & purificação , Animais , Antígenos CD/biossíntese , Antígenos CD/química , Antígenos CD/genética , Antígenos CD/isolamento & purificação , Apirase/biossíntese , Apirase/química , Apirase/genética , Apirase/isolamento & purificação , Células COS , Chlorocebus aethiops , Escherichia coli , Leishmania infantum/enzimologia , Proteínas de Protozoários/biossíntese , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas de Protozoários/isolamento & purificação , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
3.
J Contemp Dent Pract ; 17(10): 837-843, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27794155

RESUMO

AIM: This study aims at evaluating the interexaminer agreement between radiographic and tomographic methods to determine condyle morphological variations and positioning. MATERIALS AND METHODS: The sample comprised 100 individuals aged 13 to 30 years, from the patient files of University of North Paraná. The assessment of condyles morphology and positioning was performed in images of digital panoramic radiography (DPR) and reconstructed panoramic images from the cone beam computed tomography (CBCT) scans, by using the Dolphin three-dimensional (3D) program. The condyle morphology was categorized as flat, convex, and angular as well as its positioning classified into anterior, posterior, and concentric. Three calibrated examiners performed this subjective evaluation. After that, another examiner performed an objective assessment of the condyles positioning using tomographic sagittal scans of the condyles, applying the same 3D program. This objective evaluation of the condyle position, considered the gold standard (GS), was achieved by using a formula based on the measurement values of the joint spaces, anterior and posterior. The kappa test was used to assess the interexaminer agreement in determining the condyles morphology and positioning, as well as between the condyle positioning results determined by the examiners and the GS. RESULTS: The results showed poor agreement among examiners and between the subjective and objective condyle positioning evaluation. CONCLUSION: It was concluded that the panoramic radiography (PR), either digitalized or reconstructed from CBCT scans, is not suitable for determining variations in condyle morphology and position. CLINICAL SIGNIFICANCE: Whenever it is necessary to evaluate the mandibular condyle during the orthodontic screening, the orthodontist should consider another image modality better than the PR.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Côndilo Mandibular/diagnóstico por imagem , Radiografia Dentária Digital , Radiografia Panorâmica , Adolescente , Adulto , Feminino , Humanos , Imageamento Tridimensional , Masculino , Variações Dependentes do Observador , Adulto Jovem
4.
Gene Ther ; 21(12): 1041-50, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25273354

RESUMO

Familial amyloidotic polyneuropathy (FAP) is a neurodegenerative disorder characterized by extracellular deposition of amyloid fibrils composed by mutated transthyretin (TTR) mainly in the peripheral nervous system. At present, liver transplantation is still the standard treatment to halt the progression of clinical symptoms in FAP, but new therapeutic strategies are emerging, including the use of TTR stabilizers. Here we propose to establish a new gene therapy approach using adeno-associated virus (AAV) vectors to deliver the trans-suppressor TTR T119M variant to the liver of transgenic TTR V30M mice at different ages. This TTR variant is known for its ability to stabilize the tetrameric protein. Analysis of the gastrointestinal tract of AAV-treated animals revealed a significant reduction in deposition of TTR non-fibrillar aggregates in as much as 34% in stomach and 30% in colon, as well as decreased levels of biomarkers associated with TTR deposition, namely the endoplasmic reticulum stress marker BiP and the extracellular matrix protein MMP-9. Moreover, we showed with different studies that our approach leads to an increase in tetrameric and more stable forms of TTR, in favor of destabilized monomers. Altogether our data suggest the possibility to use this gene therapy approach in a prophylactic manner to prevent FAP pathology.


Assuntos
Neuropatias Amiloides Familiares/terapia , Terapia Genética/métodos , Pré-Albumina/genética , Neuropatias Amiloides Familiares/genética , Animais , Dependovirus/genética , Modelos Animais de Doenças , Eletroforese em Gel Bidimensional , Estresse do Retículo Endoplasmático/genética , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Regulação da Expressão Gênica , Técnicas de Transferência de Genes , Marcadores Genéticos , Vetores Genéticos , Fígado/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Transgênicos , Sistema Nervoso Periférico/metabolismo , Pré-Albumina/metabolismo , Proteômica
5.
Virus Res ; 140(1-2): 57-63, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19041916

RESUMO

Porcine circovirus 2 (PCV2) is the major causative agent of postweaning multisystemic wasting syndrome (PMWS) and is associated with different syndromes affecting pigs. The PCV2 genome has three main open reading frames (ORFs) among which the ORF2 encodes the capsid protein. In this study, the ORF2 nucleotide sequences of 30 Brazilian isolates were analyzed. The sequences were compared to other GenBank sequences using phylogenic and phylogeographic approaches. Our results show high sequence variability in Brazil, since, in this work, the Brazilian isolates were classified into subgroup 1AB, 2D and 2, which reveals that the virus was introduced in Brazil more than once. On the other hand, most of Brazilian isolates seem to be derived from only one introduction. According to the data from the Pig Breeders' Association, the multiple introductions of the virus probably occurred through the import of animals with the asymptomatic form of the virus or through the import of contaminated semen. The results point to the necessity of implementing programs aimed at selecting sows in order to avoid the import of animals infected by Group 1 PCV2.


Assuntos
Circovirus/classificação , Circovirus/genética , Variação Genética , Filogenia , Animais , Brasil , Clonagem Molecular , DNA Viral/genética , Genoma Viral , Geografia , Haplótipos , Fases de Leitura Aberta , Síndrome Definhante Multissistêmico de Suínos Desmamados/virologia , Análise de Sequência de DNA , Suínos/virologia
6.
Clin Genet ; 75(2): 150-6, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19215249

RESUMO

Mutations in the gene that encodes Fibroblast Growth Factor Receptor 3 (FGFR3) are associated with Achondroplasia (MIM 100800), Hypochondroplasia (MIM 146000), Muenke Syndrome (MIM 602849), Thanatophoric Dysplasia (MIM 187600, MIM 187601) and Lacrimo-Auriculo-Dento-Digital Syndrome (MIM 149730).Here we report a clinical and molecular study in a large cohort of 125 Portuguese patients with these skeletal disorders. The identification of the P250R mutation allowed the confirmation of the Muenke Syndrome in 9 out of the 52 cases referred. Two known mutations were found in the Thanatophoric Dysplasia referred cases. No mutations were identified in the LADD syndrome patient. In Achondroplasia and Hypochondroplasia, genetic heterogeneity was present amongst the 70 clinically diagnosed patients with 5 different mutations identified. As in other studies, complex phenotypic heterogeneity amongst patients carrying the same gene defect was observed. In several cases, the new amino acids encoded, as a consequence of mutations, were related to the severity of patients' phenotype. The presence of 10 misdiagnosed cases emphasizes the importance of performing mutation analysis of the hotspot regions responsible for both dysplasias (Ach and Hch). For patients with an unquestionable clinical diagnosis, lacking the most common mutations, a complete screening of FGFR3 is necessary.


Assuntos
Anormalidades Musculoesqueléticas/diagnóstico , Anormalidades Musculoesqueléticas/genética , Mutação , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Acondroplasia/diagnóstico , Acondroplasia/genética , Adolescente , Adulto , Idoso , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Portugal , Displasia Tanatofórica/diagnóstico , Displasia Tanatofórica/genética
7.
Braz J Med Biol Res ; 50(3): e5854, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28225891

RESUMO

Functional food intake has been highlighted as a strategy for the prevention of cardiovascular diseases by reducing risk factors. In this study, we compared the effects of oral treatment with soy milk and simvastatin on dyslipidemia, left ventricle remodeling and atherosclerotic lesion of LDL receptor knockout mice (LDLr-/-) fed a hyperlipidic diet. Forty 3-month old male LDLr-/- mice were distributed into four groups: control group (C), in which animals received standard diet; HL group, in which animals were fed a hyperlipidic diet; HL+SM or HL+S groups, in which animals were submitted to a hyperlipidic diet plus soy milk or simvastatin, respectively. After 60 days, both soy milk and simvastatin treatment prevented dyslipidemia, atherosclerotic lesion progression and left ventricle hypertrophy in LDLr-/- mice. These beneficial effects of soy milk and simvastatin were associated with reduced oxidative stress and inflammatory state in the heart and aorta caused by the hyperlipidic diet. Treatment with soy milk was more effective in preventing HDLc reduction and triacylglycerol and VLDLc increase. On the other hand, simvastatin was more effective in preventing an increase in total cholesterol, LDLc and superoxide production in aorta, as well as CD40L both in aorta and left ventricle of LDLr-/-. In conclusion, our results suggest a cardioprotective effect of soy milk in LDLr-/- mice comparable to the well-known effects of simvastatin.


Assuntos
Anticolesterolemiantes/administração & dosagem , Aterosclerose/prevenção & controle , Dieta , Receptores de LDL/sangue , Sinvastatina/administração & dosagem , Leite de Soja/administração & dosagem , Remodelação Ventricular/fisiologia , Animais , Masculino , Camundongos , Camundongos Knockout
8.
Hum Exp Toxicol ; 35(12): 1319-1327, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26860686

RESUMO

Bixin is a natural red pigment extracted from annatto. Although it is widely used as a coloring agent in food, there are few studies about the effect of this carotenoid on DNA. This study aimed to investigate the effects of bixin on cytotoxicity and genotoxicity induced by doxorubicin in HL60 cells. At concentrations above 0.3 µg/mL, bixin demonstrated cytotoxic effects in HL60 cells. Furthermore, this carotenoid was neither mutagenic nor genotoxic to HL60 cells and reduced the DNA damage induced by doxorubicin. Bixin and doxorubicin showed no apoptotic effect in HL60 cells, but the simultaneous combined treatments showed an increase in the percentage of apoptotic cells. In conclusion, our results showed that bixin modulates the cytotoxicity of doxorubicin via induction of apoptosis. The results of this study provide more knowledge about the toxic effects of anticancer treatments and how the natural compounds can be useful on these therapeutic approaches.


Assuntos
Antibióticos Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Carotenoides/farmacologia , Dano ao DNA/efeitos dos fármacos , Doxorrubicina/toxicidade , Apoptose/genética , Carotenoides/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Ensaio Cometa , Células HL-60 , Humanos , Microscopia de Fluorescência
9.
J Neurol ; 263(9): 1847-61, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27357003

RESUMO

Cerebrospinal fluid (CSF) 14-3-3 protein supports sporadic Creutzfeldt-Jakob (sCJD) diagnosis, but often leads to weak-positive results and lacks standardization. In this study, we explored the added diagnostic value of Total Tau (t-Tau) and phosphorylated Tau (p-Tau) in sCJD diagnosis, particularly in the cases with inconclusive 14-3-3 result. 95 definite sCJD and 287 patients without prion disease (non-CJD) were included in this study. CSF samples were collected in routine clinical diagnosis and analysed for 14-3-3 detection by Western blot (WB). CSF t-Tau and p-Tau were quantified by commercial ELISA kits and PRNP and APOE genotyping assessed by PCR-RFLP. In a regression analysis of the whole cohort, 14-3-3 protein revealed an overall accuracy of 82 % (sensitivity = 96.7 %; specificity = 75.6 %) for sCJD. Regarding 14-3-3 clear positive results, we observed no added value either of t-Tau alone or p-Tau/t-Tau ratio in the model. On the other hand, considering 14-3-3 weak-positive cases, t-Tau protein increased the overall accuracy of 14-3-3 alone from 91 to 94 % and specificity from 74 to 93 % (p < 0.05), with no sensitivity improvement. However, inclusion of p-Tau/t-Tau ratio did not significantly improve the first model (p = 0.0595). Globally, t-Tau protein allowed a further discrimination of 65 % within 14-3-3 inconclusive results. Furthermore, PRNP MV genotype showed a trend to decrease 14-3-3 sensitivity (p = 0.051), but such effect was not seen on t-Tau protein. In light of these results, we suggest that t-Tau protein assay is of significant importance as a second marker in identifying 14-3-3 false-positive results among sCJD probable cases.


Assuntos
Proteínas 14-3-3/líquido cefalorraquidiano , Síndrome de Creutzfeldt-Jakob/líquido cefalorraquidiano , Síndrome de Creutzfeldt-Jakob/diagnóstico , Erros de Diagnóstico/prevenção & controle , Proteínas tau/líquido cefalorraquidiano , Adulto , Idoso , Idoso de 80 Anos ou mais , Apolipoproteínas E/genética , Biomarcadores/líquido cefalorraquidiano , Western Blotting , Estudos de Coortes , Síndrome de Creutzfeldt-Jakob/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Técnicas de Genotipagem , Humanos , Masculino , Pessoa de Meia-Idade , Fosforilação , Proteínas Priônicas/genética , Análise de Regressão , Sensibilidade e Especificidade , Adulto Jovem
10.
Neuroscience ; 322: 398-407, 2016 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-26940479

RESUMO

Protein 14-3-3 is a reliable marker of rapid neuronal damage, specifically increased in cerebrospinal fluid (CSF) of sporadic Creutzfeldt-Jakob disease (sCJD) patients. Its detection is usually performed by Western Blot (WB), prone to methodological issues. Our aim was to evaluate the diagnostic performance of a recently developed quantitative enzyme-linked immunosorbent (ELISA) assay for 14-3-3γ, in comparison with WB and other neurodegeneration markers. CSF samples from 145 patients with suspicion of prion disease, later classified as definite sCJD (n=72) or Non-prion diseases (Non-CJD; n=73) comprised our population. 14-3-3 protein was determined by WB and ELISA. Total Tau (t-Tau) and phosphorylated Tau (p-Tau) were also evaluated. Apolipoprotein E gene (ApoE) and prionic protein gene (PRNP) genotyping was assessed. ELISA 14-3-3γ levels were significantly increased in sCJD compared to Non-CJD patients (p<0.001), showing very good accuracy (AUC=0.982; sensitivity=97%; specificity=94%), and matching WB results in 81% of all cases. It strongly correlated with t-Tau and p-Tau (p<0.0001), showing slightly higher specificity (14-3-3 WB - 63%; Tau - 90%; p-Tau/t-Tau ratio - 88%). From WB inconclusive results (n=44), ELISA 14-3-3γ correctly classified 41 patients. Additionally, logistic regression analysis selected ELISA 14-3-3γ as the best single predictive marker for sCJD (overall accuracy=93%). ApoE and PRNP genotypes did not influence ELISA 14-3-3γ levels. Despite specificity for 14-3-3γ isoform, ELISA results not only match WB evaluation but also help discrimination of inconclusive results. Our results therefore reinforce this assay as a single screening test, allowing higher sample throughput and unequivocal results.


Assuntos
Proteínas 14-3-3/líquido cefalorraquidiano , Síndrome de Creutzfeldt-Jakob/líquido cefalorraquidiano , Ensaio de Imunoadsorção Enzimática/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Apolipoproteínas E/genética , Biomarcadores/líquido cefalorraquidiano , Western Blotting , Criança , Síndrome de Creutzfeldt-Jakob/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosforilação , Proteínas Priônicas/genética , Sensibilidade e Especificidade , Adulto Jovem , Proteínas tau/líquido cefalorraquidiano
11.
Genes Brain Behav ; 15(7): 669-77, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27415614

RESUMO

Pseudohypoparathyroidism type 1b (PHP1b) is characterized by hypocalcemia, hyperphosphatemia, increased levels of circulating parathyroid hormone (PTH), and no skeletal or developmental abnormalities. The goal of this study was to perform a full characterization of a familial case of PHP1b with neurological involvement and to identify the genetic cause of disease. The initial laboratory profile of the proband showed severe hypocalcemia, hyperphosphatemia and normal levels of PTH, which was considered to be compatible with primary hypoparathyroidism. With disease progression the patient developed cognitive disturbance, PTH levels were found to be slightly elevated and a picture of PTH resistance syndrome seemed more probable. The diagnosis of PHP1b was established after the study of family members and blunted urinary cAMP results were obtained in a PTH stimulation test. Integration of whole genome genotyping and exome sequencing data supported this diagnosis by revealing a novel homozygous missense mutation in PTH1R (p.Arg186His) completely segregating with the disease. Here, we demonstrate segregation of a novel mutation in PTH1R with a phenotype of PHP1b presenting with neurological symptoms, but no bone defects. This case represents the extreme end of the spectrum of cognitive impairment in PTH dysfunction and defines a possible novel form of PHP1b resulting from the impaired interaction between PTH and PTH1R.


Assuntos
Mutação , Pseudo-Hipoparatireoidismo/genética , Receptor Tipo 1 de Hormônio Paratireóideo/genética , Idoso , Idoso de 80 Anos ou mais , Feminino , Genoma , Homozigoto , Humanos , Hiperfosfatemia/genética , Hipocalcemia/genética , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/genética , Hormônio Paratireóideo/metabolismo , Linhagem , Pseudo-Hipoparatireoidismo/sangue , Pseudo-Hipoparatireoidismo/metabolismo , Receptor Tipo 1 de Hormônio Paratireóideo/metabolismo , Pseudo-Hipoparatireoidismo
12.
Biochim Biophys Acta ; 1097(3): 224-6, 1991 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-1681909

RESUMO

A basic transthyretin (TTR) variant, apparently non-pathogenic, has been reported in a German family. Protein analysis of this TTR variant revealed the substitution of arginine for proline at position 102 of the TTR polypeptide chain. This result was confirmed by DNA analysis of PCR amplified DNA.


Assuntos
Arginina/genética , Variação Genética , Pré-Albumina/genética , Amiloidose/genética , Sequência de Bases , Éxons/genética , Feminino , Testes Genéticos , Alemanha , Humanos , Dados de Sequência Molecular , Mutação/genética , Mapeamento de Peptídeos , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Gravidez , Prolina/genética
13.
Curr Drug Targets CNS Neurol Disord ; 4(5): 587-96, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16266291

RESUMO

In transthyretin (TTR) amyloidosis TTR variants deposit as amyloid fibrils giving origin, in most cases, to peripheral polyneuropathy, cardiomyopathy, carpal tunnel syndrome and/or amyloid deposition in the eye. More than eighty TTR variants are known, most of them being pathogenic. The mechanism of TTR fibril formation is still not completely elucidated. However it is widely accepted that the amino acid substitutions in the TTR variants contribute to a destabilizing effect on the TTR tetramer molecule, which in particular conditions dissociate into non native monomeric intermediates that aggregate and polymerize in amyloid fibrils that further elongate. Since this is a multi-step process there is the possibility to impair TTR amyloid fibril formation at different stages of the process namely by tetramer stabilization, inhibition of fibril formation or fibril disruption. Till now the only efficient therapy available is liver transplant when performed in an early phase of the onset of the disease symptoms. Since this is a very invasive therapy alternatives are desirable. In that sense, several compounds have been proposed to impair amyloid formation or disruption. Based on the proposed mechanism for TTR amyloid fibril formation we discuss the action of some of the proposed TTR stabilizers such as derivatives of some NSAIDs (diflunisal, diclofenac, flufenamic acid, and derivatives) and the action of amyloid disrupters such as 4'-iodo-4'-deoxydoxorubicin (I-DOX) and tetracyclines. Among all these compounds, TTR stabilizers seem to be the most interesting since they would impair very early the process of amyloid formation and could also have a prophylactic effect.


Assuntos
Amiloide/metabolismo , Amiloidose/tratamento farmacológico , Pré-Albumina/metabolismo , Dobramento de Proteína , Amiloidose/metabolismo , Animais , Humanos , Pré-Albumina/farmacologia , Isoformas de Proteínas
14.
J Clin Endocrinol Metab ; 77(2): 484-8, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8102146

RESUMO

Recently, a transthyretin variant, TTR Met 119, in which methionine substitutes for threonine 119, a component of the protein's iodothyronine binding site, was identified in individuals with transient euthyroid hyperthyroxinemia. Healthy carriers of Met 119 have normal serum thyroid hormone concentrations, but two studies of Met 119 carriers have differed as to whether T4 binding to TTR is increased. An additional kindred has been identified by hybrid isoelectric focusing in an ongoing screening program for TTR variants in the Portuguese population with TTR Met 30 associated familial amyloidotic polyneuropathy. Cyanogen bromide peptide mapping and DNA restriction length polymorphism analyses showed that the propositus was a compound heterozygote for two TTR variants: Asn 90 and Met 119. Family analysis revealed that he inherited the TTR Met 119 variant from the mother and the TTR Asn 90 variant from the father. Neither the compound heterozygote nor his parents had symptoms of familial amyloidotic polyneuropathy. Serum dialysis with stepwise saturation of iodothyronine binding sites confirmed that TTR binding of T4 is increased in TTR Met 119. The increased binding is due to a higher TTR concentration rather than an increased association constant for T4. Because of the small proportion of serum T4 bound by TTR, increased T4 binding by TTR did not affect the ratio of free to bound T4 or T4 concentrations. In contrast, plasma retinol binding protein, almost all of which is bound by TTR, was elevated. The Asn 90 mutation does not affect either the concentration or the hormone binding characteristics of the protein. Possible long-term effects of these mutations and the combined heterozygotic state remain to be determined.


Assuntos
Metionina/química , Pré-Albumina/química , Tiroxina/metabolismo , Amiloidose/genética , Asparagina , Sítios de Ligação/genética , DNA/análise , Feminino , Genótipo , Heterozigoto , Humanos , Hipertireoxinemia/metabolismo , Focalização Isoelétrica , Masculino , Doenças do Sistema Nervoso/genética , Linhagem , Mutação Puntual , Polimorfismo de Fragmento de Restrição , Portugal , Pré-Albumina/genética , Albumina Sérica/análise , Tireotropina/sangue , Tri-Iodotironina/sangue
15.
Eur J Hum Genet ; 8(1): 49-53, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10713887

RESUMO

Mutation searching was performed in the hMSH2 and hMLH1 genes in 20 Portuguese families representing 124 registered affected individuals. Of the 20, 16 fulfilled the classic 'Amsterdam' criteria for HNPCC, whereas the remaining four families satisfied a modified set of criteria. These criteria required a CRC diagnosed before age 50 years and cancers diagnosed in two other relatives within the HNPCC spectrum. A multi-method approach was performed using the protein truncation test (PTT), single strand conformation polymorphism (SSCP) with two different sets of conditions, heteroduplex analysis (HA) and denaturing gradient gel electrophoresis (DGGE). Putative phenotype-genotype correlations were also explored. Ten different germline mutations were identified. Six of these were found in hMLH1 in seven families and four in hMSH2 in four families. SSCP and DGGE had the highest diagnostic yields with the percentage of variants detected above 67% and together HA and PTT had the lowest. No single technique detected all variants. Trends for the absence of extracolonic manifestations were observed in families carrying hMLH1 germline mutations (four of seven in hMLH1 vs one of four in hMSH2). Most of the families with rectal cancer were associated with hMLH1 (six of seven in hMLH1 vs two of four in hMSH2). A multi-technique approach is necessary to identify a high percentage of germline mutations. Seven novel mutations were found in this Portuguese population.


Assuntos
Pareamento Incorreto de Bases , Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo do DNA , Proteínas de Ligação a DNA , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Transporte , DNA/análise , DNA/sangue , Análise Mutacional de DNA/métodos , Feminino , Humanos , Masculino , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS , Proteínas Nucleares , Polimorfismo Conformacional de Fita Simples , Portugal , RNA/análise , RNA/sangue
16.
Virus Res ; 55(1): 49-60, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9712511

RESUMO

Over the last few years we have utilized a system to genetically engineer foot-and-mouth disease virus (FMDV) to produce live-attenuated vaccine candidates. These candidates have been generated in the genetic background of a tissue culture-adapted strain of serotype A12 virus. Based on this A12 system, we created a virus lacking the sequence encoding the leader (L) proteinase (Piccone et al., 1995), and demonstrated that this leaderless virus, A12-LLV2 was avirulent in bovine and swine, and could be used as an attenuated vaccine (Mason et al., 1997; Chinsangaram et al., 1998). The current study shows that a similar leader-deleted chimeric virus containing the genome of the type A12 virus with a substituted type O1 capsid coding region from a bovine-virulent virus can be constructed, and that the virus has low, but detectable virulence in swine. A second chimera specifying a tissue culture-adapted type O1 capsid lacking the RGD cell binding site, was avirulent in swine, but was not sufficiently immunogenic to provide protection from challenge. These results are described with respect to mechanisms of attenuation and antigen formation in live-attenuated virus-inoculated animals.


Assuntos
Aphthovirus/imunologia , Capsídeo/genética , Endopeptidases/genética , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Substituição de Aminoácidos , Animais , Aphthovirus/genética , Bovinos , Linhagem Celular , Cricetinae , Febre Aftosa/prevenção & controle , Deleção de Genes , Engenharia Genética , Imunidade Ativa , Integrinas/genética , Sorotipagem , Suínos , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/isolamento & purificação , Vacinas Sintéticas/genética , Vacinas Sintéticas/isolamento & purificação , Vacinas Virais/genética , Vacinas Virais/isolamento & purificação , Virulência
17.
Eur J Endocrinol ; 135(2): 226-30, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8810738

RESUMO

Thyroxine (T4) binding is a well-characterized function of transthyretin (TTR) and has been used to assess structural alterations of TTR variants. Most TTR variants deposit as amyloid fibrils originating different forms of hereditary amyloidosis. It has been hypothesized that amino acid substitutions in the TTR variants induce structural alterations that may be responsible for the amyloidogenicity of the mutant proteins. To test for structural alterations in TTR, we studied T4 binding to TTR variants both in whole serum and in isolated form obtained from heterozygotic carriers of amyloidogenic and non-amyloidogenic variants and compared the binding with the corresponding homozygotic recombinant variants. The results obtained indicated a normal T4 binding affinity for heterozygotic TTR Ala 49, TTR Leu 68, TTR Ala 71 and TTR Arg 102. Concerning TTR Pro 55 and TTR Met 111, we found a consistent decrease in binding affinity. These results were more pronounced for the equivalent recombinant proteins. Recombinant TTR Pro 55 did not show specific binding to T4 and recombinant TTR Met 111 presented very low binding affinity. Neither TTR Pro 55 nor TTR Met 111 are localized in the T4 binding channel, thus structural alterations induced by these mutations should be transmitted to the binding channel interfering with T4 binding. The results now reported, together with ongoing structural data by X-ray analyses on mutants Pro 55 and Met 111 and future binding studies with other ligands, will contribute to the elucidation of the structure and function of TTR, particularly in thyroid hormone metabolism.


Assuntos
Variação Genética , Pré-Albumina/genética , Pré-Albumina/metabolismo , Tiroxina/metabolismo , Sequência de Aminoácidos , Amiloide/biossíntese , Ligação Competitiva , Cromatografia Líquida de Alta Pressão , Heterozigoto , Homozigoto , Humanos , Proteínas Recombinantes , Recombinação Genética , Tiroxina/sangue
18.
Braz J Med Biol Res ; 25(11): 1107-12, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1342590

RESUMO

Milk serum proteins such as alpha-lactalbumin (ALA) and beta-lactoglobulin (BLG) present biochemical polymorphism which is under the control of codominant autosomal alleles. In the present report, we propose modifications of traditional electrophoretic techniques such as increasing the running gel concentration from 5 to 10% and the addition of 5 M urea to the stacking gel, which permitted the detection of two variants (A and B) at the ALA and BLG loci. About 8 microliters of milk serum (6 mg/ml protein) and 10 microliters of total fresh milk were applied. Bovine serum albumin (BSA) and immunolactoglobulins (ILG) could also be discriminated. Total fresh milk was as useful as the purified serum milk proteins for the discrimination of ALA and BLG serum milk protein polymorphism by alkaline vertical slab polyacrylamide gel electrophoresis. However, BSA and ILG ran with caseins, which prevented their characterization in this system.


Assuntos
Eletroforese Descontínua/métodos , Eletroforese em Gel de Poliacrilamida/métodos , Variação Genética , Proteínas do Leite/análise , Animais , Bovinos , Feminino , Lactalbumina/análise , Lactoglobulinas/análise , Proteínas do Leite/genética
19.
Med Clin (Barc) ; 101(15): 581-3, 1993 Nov 06.
Artigo em Espanhol | MEDLINE | ID: mdl-8255113

RESUMO

The first liver transplantation carried out in Spain for the treatment of type I familial amyloidotic polyneuropathy (FAP I) is presented. The reason for the operation was based on the liver being responsible for the synthesis of abnormal transtirretin (TTR) constituting the peculiar amyloid of the disease. Following transplantation a rapid and noticeable decrease in abnormal TTR was observed and the evolution of the clinical picture after 18 months of surgery is favorable with progressive improvement of the neurologic symptoms and normal function of the graft. These encouraging results coincide with those of the Swedish group of Umea, the pioneer of this procedure.


Assuntos
Neuropatias Amiloides/cirurgia , Transplante de Fígado , Adulto , Neuropatias Amiloides/sangue , Humanos , Masculino , Linhagem , Pré-Albumina/metabolismo
20.
J Nematol ; 28(2): 177-89, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19277133

RESUMO

A root-knot nematode parasitizing coffee in Paran State, Brazil, is described as Meloidogyne paranaensis n. sp. The suggested common name is Paraná coffee root-knot nematode. The perineal pattern is similar to that of M. incognita; the labial disc and medial lips of the female are fused and asymmetric and rectangular; the lateral lips are small, triangular, and fused laterally with the head region. The female stylet is 15.0-17.5 mum long, with broad, distinctly set-off knobs; the distance from the dorsal esophageal gland orifice (DGO) to the stylet base is 4.2-5.5 mum. Males have a high, round head cap continuous with the body contour. The labial disc is fused with the medial lips to form an elongate lip structure. The head region is frequently marked by an incomplete annulation. The stylet is robust, 20-27 mum long, usually with round to transversely elongate knobs, sometimes with one or two projections protruding from the shaft. The stylet length of second-stage juveniles is 13-14 mum, the distance of the DGO to the stylet base is 4.0-4.5 mum, and the tail length is 48-51 mum. Biochemically, the esterase (F) and malate dehydrogenase (N) phenotypes are the most useful characters to differentiate M. paranaensis from other species. However, the esterase phenotype appears similar to that of M. konaensis. Reproduction is by mitotic parthenogenesis, 3n = 50-52. In differential host tests, tobacco, watermelon, and tomato were good hosts, whereas cotton, pepper, and peanut were nonhosts.

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