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1.
Metab Brain Dis ; 37(4): 1155-1161, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35275349

RESUMEN

Maple Syrup Urine Disease (MSUD) is an autosomal recessive inherited disorder caused by a deficiency in the activity of the branched-chain alpha-ketoacid dehydrogenase complex leading to the accumulation of branched-chain amino acids (BCAA) leucine, isoleucine, and valine and their respective branched-chain α-ketoacids and corresponding hydroxy acids. Considering that Danio rerio, known as zebrafish, has been widely used as an experimental model in several research areas because it has favorable characteristics that complement other experimental models, this study aimed to evaluate oxidative stress parameters in zebrafish exposed to high levels of leucine (2 mM and 5 mM), in a model similar of MSUD. Twenty-four hours after exposure, the animals were euthanized, and the brain content dissected for analysis of oxidative stress parameters: thiobarbituric acid reactive substances (TBARS), 2',7'-dichlorofluorescein oxidation assay (DCF); content of sulfhydryl, and superoxide dismutase (SOD) and catalase (CAT) activities. Animals exposed to 2 mM and 5 mM leucine showed an increase in the measurement of TBARS and decreased sulfhydryl content. There were no significant changes in DCF oxidation. In addition, animals exposed to 2 mM and 5 mM leucine were found to have decreased SOD activity and increased CAT activity. Based on these results, exposure of zebrafish to high doses of leucine can act as a promising animal model for MSUD, providing a better understanding of the toxicity profile of leucine exposure and its use in future investigations and strategies related to the pathophysiology of MSUD.


Asunto(s)
Enfermedad de la Orina de Jarabe de Arce , Pez Cebra , Animales , Antioxidantes/farmacología , Encéfalo/metabolismo , Leucina/metabolismo , Leucina/farmacología , Enfermedad de la Orina de Jarabe de Arce/metabolismo , Estrés Oxidativo , Superóxido Dismutasa/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Pez Cebra/metabolismo
2.
Mediators Inflamm ; 2019: 7305028, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30881226

RESUMEN

Macrophage migration inhibitory factor (MIF) plays an important pathophysiological role in pulmonary hypertension (PHT). Previously, we demonstrated that serum MIF is increased in pediatric PHT associated with congenital heart disease (CHD). In the present study, we determined possible associations between MIF levels, hemodynamic and histological parameters, and mitochondrial carbamyl-phosphate synthetase I (CPSI) T1405N polymorphism in a similar population. The asparagine 1405 variant (related to A alleles in the C-to-A transversion) has been shown to be advantageous in pediatric PHT compared to the threonine 1405 variant (C alleles). Forty-one patients were enrolled (aged 2-36 months) and subsequently divided into 2 groups after diagnostic evaluation: the high-pulmonary blood flow (high PBF) group (pulmonary-to-systemic blood flow ratio 2.58 (2.21-3.01), geometric mean with 95% CI) and the high-pulmonary vascular resistance (high PVR) group (pulmonary vascular resistance 6.12 (4.78-7.89) Wood units × m2). Serum MIF was measured using a chemiluminescence assay. The CPSI polymorphism was analyzed by polymerase chain reaction followed by high-resolution melting analysis. Medial hypertrophy of pulmonary arteries was assessed by the histological examination of biopsy specimens. Serum MIF was elevated in patients compared to controls (p = 0.045), particularly in the high-PVR group (n = 16) (p = 0.022) and in subjects with the AC CPSI T1405N genotype (n = 16) compared to those with the CC genotype (n = 25) (p = 0.017). Patients with high-PVR/AC-genotype profile (n = 9) had the highest MIF levels (p = 0.030 compared with the high-PBF/CC-genotype subgroup, n = 18). In high-PVR/AC-genotype patients, the medial wall thickness of intra-acinar pulmonary arteries was directly related to MIF levels (p = 0.033). There were no patients with the relatively rare AA genotype in the study population. Thus, in the advantageous scenario of the asparagine 1405 variant (AC heterozygosity in this study), heightened pulmonary vascular resistance in CHD-PHT is associated with medial hypertrophy of pulmonary arteries where MIF chemokine very likely plays a biological role.


Asunto(s)
Cardiopatías Congénitas/sangre , Cardiopatías Congénitas/genética , Hipertensión Pulmonar/sangre , Oxidorreductasas Intramoleculares/sangre , Factores Inhibidores de la Migración de Macrófagos/sangre , Preescolar , Predisposición Genética a la Enfermedad/genética , Genotipo , Hemodinámica/genética , Hemodinámica/fisiología , Humanos , Hipertensión Pulmonar/genética , Lactante
3.
An Acad Bras Cienc ; 88(1): 323-34, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26959313

RESUMEN

The high variability of HIV-1 as well as the lack of efficient repair mechanisms during the stages of viral replication, contribute to the rapid emergence of HIV-1 strains resistant to antiretroviral drugs. The selective pressure exerted by the drug leads to fixation of mutations capable of imparting varying degrees of resistance. The presence of these mutations is one of the most important factors in the failure of therapeutic response to medications. Thus, it is of critical to understand the resistance patterns and mechanisms associated with them, allowing the choice of an appropriate therapeutic scheme, which considers the frequency, and other characteristics of mutations. Utilizing Paraconsistents Artificial Neural Networks, seated in Paraconsistent Annotated Logic Et which has the capability of measuring uncertainties and inconsistencies, we have achieved levels of agreement above 90% when compared to the methodology proposed with the current methodology used to classify HIV-1 subtypes. The results demonstrate that Paraconsistents Artificial Neural Networks can serve as a promising tool of analysis.


Asunto(s)
Farmacorresistencia Viral/genética , VIH-1/genética , Mutación/genética , Redes Neurales de la Computación , Replicación Viral/genética , Terapia Antirretroviral Altamente Activa , VIH-1/clasificación , VIH-1/efectos de los fármacos , Humanos
4.
Eur J Haematol ; 95(6): 545-50, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25684349

RESUMEN

This open-label, prospective, phase 2 study evaluated the safety and efficacy of deferasirox (10 ± 5 mg/kg/d) in patients with hereditary hemochromatosis (HH) and iron overload refractory to or intolerant of phlebotomy. Ten patients were enrolled and all completed the 12-month treatment period. There were significant decreases from baseline to end of study (i.e., 12 months) in median serum ferritin (P < 0.001), mean transferrin saturation (P < 0.05), median liver iron concentration (P < 0.001), and mean alanine aminotransferase (P < 0.05). The median time to achieve serum ferritin reduction ≥50% compared to baseline was 7.53 months. The most common adverse events were mild, transient diarrhea (n = 5) and nausea (n = 2). No patient experienced an increase in serum creatinine that exceeded the upper limit of normal. These data confirm that deferasirox was well tolerated and effective in reducing iron burden in patients with hereditary hemochromatosis and could be a safe alternative to phlebotomy in selected patients.


Asunto(s)
Benzoatos/uso terapéutico , Hemocromatosis/complicaciones , Quelantes del Hierro/uso terapéutico , Sobrecarga de Hierro/tratamiento farmacológico , Sobrecarga de Hierro/etiología , Triazoles/uso terapéutico , Adulto , Anciano , Benzoatos/administración & dosificación , Benzoatos/efectos adversos , Biomarcadores , Deferasirox , Índices de Eritrocitos , Femenino , Hemocromatosis/diagnóstico , Hemocromatosis/genética , Proteína de la Hemocromatosis , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Quelantes del Hierro/administración & dosificación , Quelantes del Hierro/efectos adversos , Sobrecarga de Hierro/diagnóstico , Masculino , Proteínas de la Membrana/genética , Persona de Mediana Edad , Mutación , Factores de Tiempo , Resultado del Tratamiento , Triazoles/administración & dosificación , Triazoles/efectos adversos
5.
An Acad Bras Cienc ; 87(1): 351-68, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25761221

RESUMEN

Glucose uptake in peripheral tissues is dependent on the translocation of GLUT4 glucose transporters to the plasma membrane. Studies have shown the existence of two major signaling pathways that lead to the translocation of GLUT4. The first, and widely investigated, is the insulin activated signaling pathway through insulin receptor substrate-1 and phosphatidylinositol 3-kinase. The second is the insulin-independent signaling pathway, which is activated by contractions. Individuals with type 2 diabetes mellitus have reduced insulin-stimulated glucose uptake in skeletal muscle due to the phenomenon of insulin resistance. However, those individuals have normal glucose uptake during exercise. In this context, physical exercise is one of the most important interventions that stimulates glucose uptake by insulin-independent pathways, and the main molecules involved are adenosine monophosphate-activated protein kinase, nitric oxide, bradykinin, AKT, reactive oxygen species and calcium. In this review, our main aims were to highlight the different glucose uptake pathways and to report the effects of physical exercise, diet and drugs on their functioning. Lastly, with the better understanding of these pathways, it would be possible to assess, exactly and molecularly, the importance of physical exercise and diet on glucose homeostasis. Furthermore, it would be possible to assess the action of drugs that might optimize glucose uptake and consequently be an important step in controlling the blood glucose levels in diabetic patients, in addition to being important to clarify some pathways that justify the development of drugs capable of mimicking the contraction pathway.


Asunto(s)
Ejercicio Físico/fisiología , Glucosa/metabolismo , Músculo Esquelético/metabolismo , Transporte Biológico/fisiología , Glucosa/fisiología , Humanos , Resistencia a la Insulina/fisiología , Músculo Esquelético/fisiología , Transducción de Señal/fisiología
6.
Pharmacogenet Genomics ; 24(11): 548-55, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25171759

RESUMEN

BACKGROUND: A previous study reported that the myosin regulatory light chain interacting protein (MYLIP) might serve as a novel therapeutic class for treating dyslipidemia. It contributes to variations in the levels of circulating low-density lipoprotein cholesterol (LDL-C), promoting the degradation of LDL-LDLR, thus limiting absorption. The effect of genetic variation in the MYLIP gene in a disease scenario characterized by mutations in the LDLR gene has not been previously evaluated. OBJECTIVE: The aim of this study was to assess the effect of the p.N342S variant on the response to lipid-lowering therapy in Brazilian patients with heterozygous familial hypercholesterolemia (FH). PATIENTS AND METHODS: A total of 156 patients with heterozygous FH were followed up for 12 months and received lipid-lowering therapy (different doses of atorvastatin with the addition of ezetimibe in over half the patients of each genotype group). Cholesterol data were assessed, and analysis of the MYLIP rs9370867 (p.N342S) genotypes was carried out by melting curve analysis. RESULTS: Baseline total cholesterol and baseline LDL-C levels were not different between genotypes. After 1 year of treatment, LDL-C responses (expressed as mg/dl and as %) were significantly different among genotypes (AA: -79±68 and -39±27, GA: -60±79 and -27±32, and GG: -30±83 and -15±38; P=0.02 and 0.005, respectively). In addition, FH patients carrying the AA genotype were more likely to achieve LDL-C levels of less than 130 mg/dl after 1 year of treatment (75.0%) compared with patients with the GG and GA genotypes (34.5 and 34.8%, respectively; P=0.001). CONCLUSION: Our study indicates that MYLIP p.N342S might be a pharmacogenetic marker for lipid-lowering therapy in patients with FH.


Asunto(s)
Anticolesterolemiantes/uso terapéutico , Ácidos Heptanoicos/uso terapéutico , Hiperlipoproteinemia Tipo II/tratamiento farmacológico , Polimorfismo Genético , Pirroles/uso terapéutico , Ubiquitina-Proteína Ligasas/genética , Adulto , Anciano , Atorvastatina , Secuencia de Bases , Brasil , Colesterol/sangre , Cartilla de ADN , Femenino , Humanos , Hiperlipoproteinemia Tipo II/genética , Masculino , Persona de Mediana Edad
7.
Tob Induc Dis ; 222024.
Artículo en Inglés | MEDLINE | ID: mdl-38628555

RESUMEN

INTRODUCTION: Smoking cessation is the best strategy for reducing tobacco-related morbimortality. The goal of this randomized controlled trial was to test whether using the genetically favorable markers to choose a smoking cessation drug treatment (precision medicine) was superior to using the most effective drug (varenicline) in terms of abstinence rates. Additionally, combination therapy was tested when monotherapy failed. METHODS: This partially blind, single-center study randomized (1:1) 361 participants into two major groups. In the genetic group (n=184), CYP2B6 rs2279343 (genotype AA) participants started treatment with bupropion, and CHRNA4 rs1044396 (genotype CT or TT) participants started treatment with varenicline; when genetic favorable to both, participants started treatment with bupropion, and when favorable to neither, on both drugs. In the control group (n=177), participants started treatment with varenicline, regardless of genetic markers. Drug treatment lasted 12 weeks. Efficacy endpoints were abstinence rates at Weeks 4, and Weeks 8-12, biochemically validated by carbon monoxide in exhaled air. Participants who did not achieve complete abstinence at Week 4, regardless of group, were given the choice to receive combination therapy. RESULTS: Abstinence rates were 42.9% (95% CI: 36-64) in the control group versus 30.4% (95% CI: 23-37) in the genetic group at Week 4 (p=0.01); and 74% (95% CI: 67-80) versus 52% (95% CI: 49-64) at Week 12 (p<0.001), respectively. The strategy of combining drugs after Week 4 increased abstinence rates in both groups and the significant difference between genetic and control groups was maintained. CONCLUSIONS: Results show that using these selected genetic markers was inferior to starting treatment with varenicline (control group), which is currently the most effective smoking cessation drug; moreover, the addition of bupropion in cases of varenicline monotherapy failure improves the efficacy rate until the end of treatment. CLINICAL TRIAL IDENTIFIER: NCT03362099.

8.
Nicotine Tob Res ; 15(6): 1146-50, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23128516

RESUMEN

INTRODUCTION: Varenicline has a significant impact on the ability to quit smoking. However, patients may have side effects similar to nicotine withdrawal symptoms. The aim of this study was to evaluate the effectiveness of varenicline in monotherapy or in combined therapy with bupropion and/or serotonin reuptake inhibitors (SRIs) in a specific cardiovascular smoking cessation service. METHODS: It is an outcome research of 427 patients that received varenicline monotherapy or combined pharmacotherapy and were followed for 52 weeks. Patients were oriented to take varenicline until week 12. During each medical visit, the patients were evaluated and in the cases of mood changes after varenicline use, SRIs were prescribed. Bupropion was combined in patients that did not achieve complete tobacco abstinence in 2 or 3 weeks after starting varenicline use or if the patient presented uncomfortable abstinent symptoms. RESULTS: The success (continuous abstinence rate in 52 weeks) in different drug regimens were: varenicline monotherapy (32.1%), varenicline + bupropion (55.0%), varenicline + SRI (50.6%), and varenicline + bupropion + SRI (57.7%). In a multivariate analysis of successful treatment predictors, compared with varenicline monotherapy, patients who used bupropion + SRI adjuvant treatment had an odds ratio (OR) of 5.05 (1.99-12.80) for a successful treatment response after 1-year follow-up, while patients who used bupropion or SRI had OR of 3.21 (1.68-6.14) and 3.58 (1.98-6.48), respectively. CONCLUSIONS: Our results suggest that adjuvant treatment to varenicline therapy may be associated with improved success in smoking cessation, especially in patients with nicotine withdrawal symptoms. These results should be tested in randomized controlled trials.


Asunto(s)
Antidepresivos de Segunda Generación/administración & dosificación , Benzazepinas/administración & dosificación , Bupropión/administración & dosificación , Agonistas Nicotínicos/administración & dosificación , Quinoxalinas/administración & dosificación , Inhibidores Selectivos de la Recaptación de Serotonina/administración & dosificación , Cese del Hábito de Fumar/métodos , Adulto , Brasil , Demografía , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Prevención del Hábito de Fumar , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico , Resultado del Tratamiento , Vareniclina
9.
Artículo en Inglés | MEDLINE | ID: mdl-37297535

RESUMEN

This study aimed to systematically review and summarize the available data regarding the influence of overweight and obesity across the lifespan on obstacle crossing during walking. Four databases were systematically searched with no limitation on publication date following the Cochrane Handbook for Systematic Reviews and PRISMA guidelines. Only full-text English-language articles published in a peer-reviewed journal were eligible. They had to compare obstacle crossing during walking by overweight or obese individuals with individuals of normal body weight. Five studies were considered eligible. All the studies assessed kinematics; only one assessed kinetics, but none investigated muscle activity or obstacle contact. Compared to normal individuals crossing obstacles, overweight or obese individuals exhibited lower velocity, shorter step length, lower cadence, and less time spent in single-limb support. They also exhibited increased step width, more time spent in double support, and greater trailing leg ground force reaction and centre of mass acceleration. Overall, the small number of included studies did not allow us to draw any conclusions. However, being overweight or obese seems to have a potentially negative influence on the kinematics of gait parameters due to a tendency to trip, fall, and suffer severe fall-related injuries when negotiating obstacles on foot in real-life environments.


Asunto(s)
Longevidad , Sobrepeso , Humanos , Sobrepeso/epidemiología , Caminata/fisiología , Obesidad/epidemiología , Marcha/fisiología , Extremidad Inferior
10.
Lipids Health Dis ; 11: 83, 2012 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-22741812

RESUMEN

BACKGROUND: A recent study investigated the MYLIP region in the Mexican population in order to fine-map the actual susceptibility variants of this locus. The p.N342S polymorphism was identified as the underlying functional variant accounting for one of the previous signals of genome-wide association studies and the N342 allele was associated with higher cholesterol concentrations in Mexican dyslipidemic individuals. To date, there is no further evaluation on this genotype-phenotype association in the literature. In this scenario, and because of a possible pharmacotherapeutic target of dyslipidemia, the main aim of this study was to assess the influence of the MYLIP p.N342S polymorphism on lipid profile in Brazilian individuals. METHODS: 1295 subjects of the general population and 1425 consecutive patients submitted to coronary angiography were selected. General characteristics, biochemical tests, blood pressures, pulse wave velocity, and coronary artery disease scores were analyzed. Genotypes for the MYLIP rs9370867 (p.N342S, c.G1025A) polymorphism were detected by high resolution melting analysis. RESULTS: No association of the MYLIP rs9370867 genotypes with lipid profile, hemodynamic data, and coronary angiographic data was found. Analysis stratified by hyperlipidemia, gender, and ethnicity was also performed and the sub-groups presented similar results. In both general population and patient samples, the MYLIP rs9370867 polymorphism was differently distributed according to ethnicity. In the general population, subjects carrying GG genotypes had higher systolic blood pressure (BP), diastolic BP, and mean BP values (129.0 ± 23.3; 84.9 ± 14.6; 99.5 ± 16.8 mmHg) compared with subjects carrying AA genotypes (123.7 ± 19.5; 81.6 ± 11.8; 95.6 ± 13.6 mmHg) (p = 0.01; p = 0.02; p = 0.01, respectively), even after adjustment for covariates. However, in analysis stratified by ethnicity, this finding was not found and there is no evidence that the polymorphism influences BP. CONCLUSION: Our findings indicate that association studies involving this MYLIP variant can present distinct results according to the studied population. In this moment, further studies are needed to reaffirm if the MYLIP p.N342S polymorphism is functional or not, and to identify other functional markers within this gene.


Asunto(s)
Sustitución de Aminoácidos , Lípidos/sangre , Polimorfismo de Nucleótido Simple , Ubiquitina-Proteína Ligasas/genética , Adulto , Anciano , Brasil , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/genética , Femenino , Estudios de Asociación Genética , Humanos , Hiperlipidemias/sangre , Hiperlipidemias/genética , Hipertensión/sangre , Hipertensión/genética , Masculino , Persona de Mediana Edad , Fenotipo , Cintigrafía , Análisis de Secuencia de ADN , Población Urbana , Rigidez Vascular/genética
11.
Int J Mol Sci ; 13(2): 1497-1511, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22408404

RESUMEN

Hereditary hemochromatosis (HH) is an autosomal recessive disorder characterized by enhanced intestinal absorption of dietary iron. Without therapeutic intervention, iron overload leads to multiple organ damage such as liver cirrhosis, cardiomyopathy, diabetes, arthritis, hypogonadism and skin pigmentation. Most HH patients carry HFE mutant genotypes: homozygosity for p.Cys282Tyr or p.Cys282Tyr/p.His63Asp compound heterozygosity. In addition to HFE gene, mutations in the genes that encode hemojuvelin (HJV), hepcidin (HAMP), transferrin receptor 2 (TFR2) and ferroportin (SLC40A1) have been associated with regulation of iron homeostasis and development of HH. The aim of this review was to identify the main gene mutations involved in the pathogenesis of type 1, 2, 3 and 4 HH and their genetic testing indication. HFE testing for the two main mutations (p.Cys282Tyr and p.His63Asp) should be performed in all patients with primary iron overload and unexplained increased transferrin saturation and/or serum ferritin values. The evaluation of the HJV p.Gly320Val mutation must be the molecular test of choice in suspected patients with juvenile hemochromatosis with less than 30 years and cardiac or endocrine manifestations. In conclusion, HH is an example that genetic testing can, in addition to performing the differential diagnostic with secondary iron overload, lead to more adequate and faster treatment.


Asunto(s)
Hemocromatosis , Hepcidinas , Antígenos de Histocompatibilidad Clase I , Proteínas de la Membrana , Mutación Missense , Patología Molecular/métodos , Receptores de Transferrina , Sustitución de Aminoácidos , Hemocromatosis/diagnóstico , Hemocromatosis/genética , Hemocromatosis/metabolismo , Hemocromatosis/patología , Proteína de la Hemocromatosis , Hepcidinas/genética , Hepcidinas/metabolismo , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/metabolismo , Humanos , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Receptores de Transferrina/genética , Receptores de Transferrina/metabolismo
12.
Neurosci Biobehav Rev ; 142: 104854, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36084846

RESUMEN

Striking an obstacle while walking can be dangerous, reflecting the higher risks of losing one's balance, tripping and falling. Particular situations during which internal resources are limited, such as in a fatigued state, may impair performance when crossing obstacles, enhancing the risks of falls or accidents. Our goal was thus to review the effects of experimentally-induced fatigue (EIF) on gait parameters during obstacle crossing by healthy individuals. We systematically searched PubMed and Web of Science databases using 'fatigue', 'obstacle crossing' and their equivalent terms to extract data from studies investigating this domain. Nine studies were found. First, EIF-related effects on kinetics, EMG and obstacle contacts have been poorly studied. Second, consistent and inconsistent results were found in the kinematic outcomes after EIF. Consistent results included reductions in stride duration and increased step width. Inconsistent results included gait velocity (no-effect vs increased), leading and trailing-foot vertical clearance (reduced vs increased) and horizontal distance from foot to the obstacle before obstacle avoidance (no-effect vs increased). These findings should be interpreted cautiously, however, due to the heterogeneity of the obstacle crossing and EIF protocols.


Asunto(s)
Marcha , Caminata , Humanos , Pie , Fenómenos Biomecánicos , Cinética
13.
Blood Cells Mol Dis ; 46(4): 302-7, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21411349

RESUMEN

BACKGROUND: p.C282Y mutation and rare variants in the HFE gene have been associated with hereditary hemochromatosis (HH). HH is also caused by mutations in other genes, such as the hemojuvelin (HJV), hepcidin (HAMP), transferrin receptor 2 (TFR2) and ferroportin (SLC40A1). The low rate homozygous p.C282Y mutation in Brazil is suggestive that mutations in non-HFE genes may be linked to HH phenotype. AIM: To screen exon-by-exon DNA sequences of HFE, HJV, HAMP, TFR2 and SLC40A1 genes to characterize the molecular basis of HH in a sample of the Brazilian population. MATERIALS AND METHODS: Fifty-one patients with primary iron overload (transferrin saturation ≥50% in females and ≥60% in males) were selected. Subsequent bidirectional DNA sequencing of HFE, HJV, HAMP, TFR2 and SLC40A1 exons was performed. RESULTS: Thirty-seven (72.5%) out of the 51 patients presented at least one HFE mutation. The most frequent genotype associated with HH was the homozygous p.C282Y mutation (n=11, 21.6%). In addition, heterozygous HFE p.S65C mutation was found in combination with p.H63D in two patients and homozygous HFE p.H63D was found in two patients as well. Sequencing in the HJV and HAMP genes revealed HJV p.E302K, HJV p.A310G, HJV p.G320V and HAMP p.R59G alterations. Molecular and clinical diagnosis of juvenile hemochromatosis (homozygous form for the HJV p.G320V) was described for the first time in Brazil. Three TFR2 polymorphisms (p.A75V, p.A617A and p.R752H) and six SLC40A1 polymorphisms (rs13008848, rs11568351, rs11568345, rs11568344, rs2304704, rs11568346) and the novel mutation SLC40A1 p.G204S were also found. CONCLUSIONS: The HFE p.C282Y in homozygosity or in heterozygosity with p.H63D was the most frequent mutation associated with HH in this sample. The HJV p.E302K and HAMP p.R59G variants, and the novel SLC40A1 p.G204S mutation may also be linked to primary iron overload but their role in the pathophysiology of HH remain to be elucidated.


Asunto(s)
Hemocromatosis/congénito , Antígenos de Histocompatibilidad Clase I/genética , Homeostasis/genética , Hierro/metabolismo , Proteínas de la Membrana/genética , Mutación , Adolescente , Adulto , Brasil/epidemiología , Niño , Preescolar , Femenino , Frecuencia de los Genes , Genotipo , Hemocromatosis/genética , Proteína de la Hemocromatosis , Humanos , Sobrecarga de Hierro/genética , Masculino , Persona de Mediana Edad , Adulto Joven
14.
BMC Med Genet ; 12: 136, 2011 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-21992719

RESUMEN

BACKGROUND: Recent studies reported the association between SLCO1B1 polymorphisms and the development of statin-induced myopathy. In the scenario of the Brazilian population, being one of the most heterogeneous in the world, the main aim here was to evaluate SLCO1B1 polymorphisms according to ethnic groups as an initial step for future pharmacogenetic studies. METHODS: One hundred and eighty-two Amerindians plus 1,032 subjects from the general urban population were included. Genotypes for the SLCO1B1 rs4149056 (c.T521C, p.V174A, exon 5) and SLCO1B1 rs4363657 (g.T89595C, intron 11) polymorphisms were detected by polymerase chain reaction followed by high resolution melting analysis with the Rotor Gene 6000® instrument. RESULTS: The frequencies of the SLCO1B1 rs4149056 and rs4363657 C variant allele were higher in Amerindians (28.3% and 26.1%) and were lower in African descent subjects (5.7% and 10.8%) compared with Mulatto (14.9% and 18.2%) and Caucasian descent (14.8% and 15.4%) ethnic groups (p<0.001 and p<0.001, respectively). Linkage disequilibrium analysis show that these variant alleles are in different linkage disequilibrium patterns depending on the ethnic origin. CONCLUSION: Our findings indicate interethnic differences for the SLCO1B1 rs4149056 C risk allele frequency among Brazilians. These data will be useful in the development of effective programs for stratifying individuals regarding adherence, efficacy and choice of statin-type.


Asunto(s)
Indígenas Sudamericanos/genética , Enfermedades Musculares/etnología , Enfermedades Musculares/genética , Transportadores de Anión Orgánico/genética , Polimorfismo de Nucleótido Simple/genética , Brasil , Cartilla de ADN/genética , Frecuencia de los Genes , Genotipo , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Desequilibrio de Ligamiento , Transportador 1 de Anión Orgánico Específico del Hígado , Enfermedades Musculares/inducido químicamente , Mutación Missense/genética , Reacción en Cadena de la Polimerasa , Temperatura de Transición
15.
BMC Med Genet ; 12: 13, 2011 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-21247447

RESUMEN

BACKGROUND: Recent studies have reported the clinical importance of CYP2C19 and ABCB1 polymorphisms in an individualized approach to clopidogrel treatment. The aims of this study were to evaluate the frequencies of CYP2C19 and ABCB1 polymorphisms and to identify the clopidogrel-predicted metabolic phenotypes according to ethnic groups in a sample of individuals representative of a highly admixtured population. METHODS: One hundred and eighty-three Amerindians and 1,029 subjects of the general population of 4 regions of the country were included. Genotypes for the ABCB1c.C3435T (rs1045642), CYP2C19*2 (rs4244285), CYP2C19*3 (rs4986893), CYP2C19*4 (rs28399504), CYP2C19*5 (rs56337013), and CYP2C19*17 (rs12248560) polymorphisms were detected by polymerase chain reaction followed by high resolution melting analysis. The CYP2C19*3, CYP2C19*4 and CYP2C19*5 variants were genotyped in a subsample of subjects (300 samples randomly selected). RESULTS: The CYP2C19*3 and CYP2C19*5 variant alleles were not detected and the CYP2C19*4 variant allele presented a frequency of 0.3%. The allelic frequencies for the ABCB1c.C3435T, CYP2C19*2 and CYP2C19*17 polymorphisms were differently distributed according to ethnicity: Amerindian (51.4%, 10.4%, 15.8%); Caucasian descent (43.2%, 16.9%, 18.0%); Mulatto (35.9%, 16.5%, 21.3%); and African descent (32.8%, 20.2%, 26.3%) individuals, respectively. As a result, self-referred ethnicity was able to predict significantly different clopidogrel-predicted metabolic phenotypes prevalence even for a highly admixtured population. CONCLUSION: Our findings indicate the existence of inter-ethnic differences in the ABCB1 and CYP2C19 variant allele frequencies in the Brazilian general population plus Amerindians. This information could help in stratifying individuals from this population regarding clopidogrel-predicted metabolic phenotypes and design more cost-effective programs towards individualization of clopidogrel therapy.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Hidrocarburo de Aril Hidroxilasas/genética , Inhibidores de Agregación Plaquetaria/metabolismo , Polimorfismo Genético , Ticlopidina/análogos & derivados , Subfamilia B de Transportador de Casetes de Unión a ATP , Adulto , Brasil , Clopidogrel , Citocromo P-450 CYP2C19 , Etnicidad/genética , Femenino , Frecuencia de los Genes , Humanos , Indígenas Sudamericanos/genética , Masculino , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/uso terapéutico , Ticlopidina/metabolismo , Ticlopidina/uso terapéutico , Población Blanca/estadística & datos numéricos
16.
Tob Prev Cessat ; 7: 33, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34017927

RESUMEN

INTRODUCTION: Varenicline effectively helps smokers quit by reducing withdrawal symptoms and blocking the reward of smoking. However, most quitters return to smoking within one year. 'Cue Restricted Smoking' is a behavioral technique designed to increase quit rates by asking smokers attempting to quit to restrict smoking to the standing position, while alone, in an isolated area facing a wall, with the cigarette as the only stimulus. METHODS: Using retrospective clinic records we compared quit rates in 281 smokers (50% males) instructed in the cue restricted smoking cessation method during 2016-2018 to quit rates in 324 smokers (46% males) advised to completely stop smoking on the target quit date which we previously used during 2011-2014. All were prescribed varenicline for 12 weeks alone, with the addition of bupropion if needed after 4 weeks. Follow-up consisted of behavioral support at 4-6 visits during active drug treatment and telephone counselling at 24 and 52 weeks. The smoking cessation rate was confirmed with exhaled carbon monoxide at the clinic visit at 12 weeks and only by telephone at 52 weeks. RESULTS: The mean age of smokers was 49 years in both groups and the number of cigarettes smoked daily was similar (18/day in the cue restricted vs 19/day in the target quit day group). The smoking cessation rate at 12 weeks was 75% in the cue restricted versus 45% in the target quit day group (relative risk, RR=1.8; 95% CI: 1.4-2.2, p<0.001). At 52 weeks the quit rate was 65% vs 34%, respectively (RR=1.9; 95% CI: 1.5-2.4, p<0.001). CONCLUSIONS: Cue restricted smoking was associated with a substantially increased chance of quitting compared with standard advice during treatment with varenicline. These results should be further studied in a randomized controlled trial.

17.
Blood Cells Mol Dis ; 45(4): 302-7, 2010 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-20843714

RESUMEN

Rare HFE variants have been shown to be associated with hereditary hemochromatosis (HH), an iron overload disease. The low frequency of the HFE p.C282Y mutation in HH-affected Brazilian patients may suggest that other HFE-related mutations may also be implicated in the pathogenesis of HH in this population. The main aim was to screen for new HFE mutations in Brazilian individuals with primary iron overload and to investigate their relationship with HH. Fifty Brazilian patients with primary iron overload (transferrin saturation>50% in females and 60% in males) were selected. Subsequent bidirectional sequencing for each HFE exon was performed. The effect of HFE mutations on protein structure were analyzed by molecular dynamics simulation and free binding energy calculations. p.C282Y in homozygosis or in heterozygosis with p.H63D were the most frequent genotypic combinations associated with HH in our sample population (present in 17 individuals, 34%). Thirty-six (72.0%) out of the 50 individuals presented at least one HFE mutation. The most frequent genotype associated with HH was the homozygous p.C282Y mutation (n=11, 22.0%). One novel mutation (p.V256I) was indentified in heterozygosis with the p.H63D mutation. In silico modeling analysis of protein behavior indicated that the p.V256I mutation does not reduce the binding affinity between HFE and ß2-microglobulin (ß2M) in the same way the p.C282Y mutation does compared with the native HFE protein. In conclusion, screening of HFE through direct sequencing, as compared to p.C282Y/p.H63D genotyping, was not able to increase the molecular diagnosis yield of HH. The novel p.V256I mutation could not be implicated in the molecular basis of the HH phenotype, although its role cannot be completely excluded in HH-phenotype development. Our molecular modeling analysis can help in the analysis of novel, previously undescribed, HFE mutations.


Asunto(s)
Antígenos de Histocompatibilidad Clase I/genética , Sobrecarga de Hierro/genética , Proteínas de la Membrana/genética , Mutación , Patología Molecular/métodos , Brasil/epidemiología , Pruebas Genéticas , Proteína de la Hemocromatosis , Antígenos de Histocompatibilidad Clase I/química , Humanos , Proteínas de la Membrana/química , Modelos Moleculares , Mutación Missense , Conformación Proteica , Análisis de Secuencia de ADN
18.
Lipids Health Dis ; 9: 128, 2010 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-21059196

RESUMEN

BACKGROUND: Cardiovascular diseases (CVD) are the main cause of death and disability in developed countries. In most cases, the progress of CVD is influenced by environmental factors and multifactorial inheritance. The purpose of this study was to investigate the association between APOE genotypes, cardiovascular risk factors, and a non-invasive measure of arterial stiffness in the Brazilian population. METHODS: A total of 1493 urban Brazilian individuals were randomly selected from the general population of the Vitoria City Metropolitan area. Genetic analysis of the APOE polymorphism was conducted by PCR-RFLP and pulse wave velocity analyzed with a noninvasive automatic device. RESULTS: Age, gender, body mass index, triglycerides, creatinine, uric acid, blood glucose, blood pressure phenotypes were no different between ε2, ε3 and ε4 alleles. The ε4 allele was associated with higher total-cholesterol (p < 0.001), LDL-C (p < 0.001), total-cholesterol/HDL-C ratio (p < 0.001), LDL/HDL-C ratio (p < 0.001), lower HDL-C values (p < 0.001) and higher risk to obesity (OR = 1.358, 95% CI = 1.019-1.811) and hyperuricemia (OR = 1.748, 95% CI = 1.170-2.611). Nevertheless, pulse wave velocity (p = 0.66) measures were no different between genotypes. The significant association between APOE genotypes and lipid levels persisted after a 5-year follow-up interval, but no interaction between time and genotype was observed for lipids longitudinal behavior. CONCLUSION: The ε4 allele of the APOE gene is associated with a worse lipid profile in the Brazilian urban population. In our relatively young sample, the observed effect of APOE genotype on lipid levels was not translated into significant effects in arterial wall stiffness.


Asunto(s)
Apolipoproteínas E/genética , Arterias/fisiopatología , Enfermedades Cardiovasculares/genética , Lípidos/sangre , Polimorfismo Genético/genética , Adulto , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Femenino , Predisposición Genética a la Enfermedad/genética , Humanos , Lípidos/genética , Masculino , Persona de Mediana Edad
19.
Clin Pharmacol Ther ; 107(6): 1420-1433, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31869433

RESUMEN

Warfarin is the most commonly used oral anticoagulant in sub-Saharan Africa. Dosing is challenging due to a narrow therapeutic index and high interindividual variability in dose requirements. To evaluate the genetic factors affecting warfarin dosing in black-Africans, we performed a meta-analysis of 48 studies (2,336 patients). Significant predictors for CYP2C9 and stable dose included rs1799853 (CYP2C9*2), rs1057910 (CYP2C9*3), rs28371686 (CYP2C9*5), rs9332131 (CYP2C9*6), and rs28371685 (CYP2C9*11) reducing dose by 6.8, 12.5, 13.4, 8.1, and 5.3 mg/week, respectively. VKORC1 variants rs9923231 (-1639G>A), rs9934438 (1173C>T), rs2359612 (2255C>T), rs8050894 (1542G>C), and rs2884737 (497T>G) decreased dose by 18.1, 21.6, 17.3, 11.7, and 19.6 mg/week, respectively, whereas rs7294 (3730G>A) increased dose by 6.9 mg/week. Finally, rs12777823 (CYP2C gene cluster) was associated with a dose reduction of 12.7 mg/week. Few studies were conducted in Africa, and patient numbers were small, highlighting the need for further work in black-Africans to evaluate genetic factors determining warfarin response.


Asunto(s)
Anticoagulantes/administración & dosificación , Citocromo P-450 CYP2C9/genética , Warfarina/administración & dosificación , Población Negra/genética , Relación Dosis-Respuesta a Droga , Humanos , Polimorfismo de Nucleótido Simple , Vitamina K Epóxido Reductasas/genética
20.
J Sports Med Phys Fitness ; 59(11): 1852-1860, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31062949

RESUMEN

BACKGROUND: Task constraints and players' asymmetry influences on lower extremity (i.e. kicking limb) kinematics during futsal instep kicking. However, support limb behavior when shooting in a futsal context was not previously investigated, and its potential role on such discrepant motor outputs is still unclear. Thus, the study aimed to compare kinematic features of the support limb and approach run between kicking a stationary and a rolling ball using dominant and non-dominant limbs. METHODS: Ten futsal players participated (21.88±2.86 years-old, 73.66±4.17 kg and 1.75±0.04 m) and performed kicks (five per limb per condition) with the dominant and non-dominant limbs in stationary and rolling ball conditions. Kinematic analysis comprised determination of support limb angular joint (hip, knee and ankle) displacement and velocity, approach run distance, angle, linear velocity, step length and width, support foot-to-ball distance, ball velocity (120 Hz) and accuracy (60 Hz). RESULTS: Hip adjustments (greater extension) in the support limb when kicking a rolling ball contributed in maintaining similar performance (e.g., ball velocity) to kicking a stationary ball, compensating for the lower approach run velocity and longer support foot to ball distance. Kicking with the non-dominant limb demonstrated a lower approach run velocity and the non-dominant support limb presented different angular motion compared to the dominant support limb in hip (< internal rotation), knee (< flexion), and ankle joints (< plantar flexion), being harmful to performance in both kicking stationary and rolling balls. CONCLUSIONS: Kicking a stationary and rolling ball presented similar performance, but compared to the dominant side, futsal instep kicks performed with the non-dominant support limb induces lower approach run velocity and inefficient angular joint motion, either harmful to performance output.


Asunto(s)
Extremidad Inferior/fisiología , Deportes/fisiología , Adulto , Tobillo/fisiología , Atletas , Rendimiento Atlético , Fenómenos Biomecánicos , Cadera/fisiología , Humanos , Rodilla/fisiología , Masculino , Rango del Movimiento Articular , Rotación , Adulto Joven
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