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1.
Arq. bras. med. vet. zootec. (Online) ; 71(1): 243-251, jan.-fev. 2019. tab
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-989382

RESUMEN

Investigaram-se os efeitos de diferentes tempos de exposição ao calor sobre o rendimento de carcaça, cortes e vísceras comestíveis e a composição química da carne de peito de frangos de corte de duas linhagens. Foram alojados 560 pintos de corte da linhagem Cobb 500 Slow® e 560 da Hubbard Flex® em 32 boxes. A partir do 14º dia, eles foram divididos nos ambientes térmicos: controle, uma hora, duas horas ou três horas diárias de estresse por calor. O rendimento de carcaça, peito sem osso, coxa e sobrecoxa com osso, asas, pés, fígado, moela e coração foi avaliado em seis aves de cada linhagem em cada ambiente térmico. Amostras foram obtidas para analisar matéria seca, extrato etéreo, proteína bruta e matéria mineral. O estresse cíclico por calor por até três horas diárias não influenciou o rendimento de carcaça, de peito sem osso, de coxa e sobrecoxa, de asa, de coração, de moela, de fígado e a composição química do peito. A linhagem Cobb 500 Slow® apresentou maior rendimento de peito. A Hubbard Flex® apresentou peito com maior percentual de matéria mineral e proteína. A linhagem Cobb é mais indicada à produção de peito, e a linhagem Hubbard à produção de frango inteiro.(AU)


The effects of different exposure periods under heat on the carcass yield, cuts and edible organs and breast chemical composition of broilers from two strains were investigated. Five hundred and sixty Cobb 500 Slow® and 560 Hubbard Flex® broiler chicks were housed in 32 pens and from the 14th day on, they were divided in thermal environments: control, 1 hour, 2 hours or 3 hours a day under heat stress. Carcass yield, boneless breast, thigh and drumstick with bone, wings, feet, liver, gizzard and heart were evaluated in six birds of each strain in each thermal environment. Samples were obtained to assess dry matter, ether extract, crude protein and mineral matter. The cyclic heat stress for up to three hours a day did not influence 33 the carcass yield, boneless breast, thigh and drumstick, wing, heart, gizzard, liver, and the breast chemical composition. Cobb 500 Slow® strain had higher breast yield. Hubbard Flex® had breast with higher percentage of mineral matter and protein. Cobb strain is best designed to breast production, and Hubbard is best for whole chicken production.(AU)


Asunto(s)
Animales , Pollos/clasificación , Pollos/fisiología , Carne/análisis , Trastornos de Estrés por Calor
2.
J Hum Hypertens ; 31(12): 826-830, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29115296

RESUMEN

Aldosterone and renin measurement is a cornerstone for primary aldosteronism (PA) diagnosis, but different thresholds are used according to different assays. A fully automated chemiluminescence (CL) immunoassay for renin and aldosterone was recently proposed, showing good performance for PA screening by aldosterone to renin ratio (ARR). This study aimed to define the accuracy of this assay in the screening and in the most popular confirmatory test of autonomous aldosterone production, the intravenous saline loading test (ivSLT). We compared aldosterone results obtained by CL vs radioimmunoassay (RIA) in hypertensive patients investigated for PA (102 baseline and 85 after ivSLT). An excellent correlation was observed between RIA and CL in the entire population for aldosterone (r=0.922) and ARR (r=0.977). For ARR, Deming regression proved a good accordance between methods and, consistent with the fit model, our previous institutional ARR cut-off of 32 (pg ml-1)/(pg ml-1) corresponded to 20 pg ml-1 mU-1 l-1 in CL assay. However, the correlation was weaker in the low end of aldosterone concentrations (r=0.676 for aldosterone <100 pg ml-1), with a concordance of ivSLT results in only 68% of patients. CL assay displays a diagnostic performance very similar to RIA for ARR screening, but it is substantially inferior in the setting of confirmatory tests of autonomous aldosterone secretion, that is, ivSLT.


Asunto(s)
Aldosterona/sangre , Hiperaldosteronismo/diagnóstico , Adulto , Anciano , Femenino , Humanos , Hiperaldosteronismo/sangre , Mediciones Luminiscentes , Masculino , Persona de Mediana Edad , Radioinmunoensayo
3.
J Thromb Haemost ; 14(4): 655-66, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27061056

RESUMEN

BACKGROUND: Plasma concentration of activated factor VII (FVIIa)-antithrombin (AT) complex has been proposed as an indicator of intravascular exposure of tissue factor. OBJECTIVES: The aims of this observational study were to evaluate (i) FVIIa-AT plasma concentration in subjects with or without coronary artery disease (CAD) and (ii) its association with mortality in a prospective cohort of patients with CAD. METHODS: FVIIa-AT levels were measured by elisa in 686 subjects with (n = 546) or without (n = 140) angiographically proven CAD. Subjects with acute coronary syndromes and those taking anticoagulant drugs at the time of enrollment were excluded. CAD patients were followed for total and cardiovascular mortality. RESULTS: There was no difference in FVIIa-AT levels between CAD (84.8 with 95% confidence interval [CI] 80.6-88.2 pmol L(-1) ) and CAD-free subjects (83.9 with 95% CI 76.7-92.8 pmol L(-1) ). Within the CAD population, during a 64-month median follow-up, patients with FVIIa-AT levels higher than the median value at baseline (≥ 79 pmol L(-1) ) had a two-fold greater risk of both total and cardiovascular mortality. Results were confirmed after adjustment for sex, age, the other predictors of mortality (hazard ratio for total mortality: 2.05 with 95% CI 1.22-3.45, hazard ratio for cardiovascular mortality 1.94 with 95% CI 1.01-3.73, with a slight improvement of C-statistic over traditional risk factors), FVIIa levels, drug therapy at discharge, and even patients using all the usual medications for CAD treatment. High FVIIa-AT levels also correlated with increased thrombin generation. CONCLUSIONS: This preliminary study suggests that plasma concentration of FVIIa-AT is a thrombophilic marker of total and cardiovascular mortality risk in patients with clinically stable CAD.


Asunto(s)
Anticoagulantes/química , Antitrombinas/química , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/mortalidad , Factor VIIa/química , Anciano , Antitrombinas/sangre , Angiografía Coronaria , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo , Trombina/química , Tromboplastina/metabolismo , Resultado del Tratamiento
4.
Meat Sci ; 100: 319-26, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25454470

RESUMEN

The effects of a pre-formulated commercial plant extract mix, composed of equal parts of oregano essential oil and sweet chestnut wood extract, on performance, oxidative status and pork quality traits were evaluated. In two 155-d studies, 60 pigs (mean liveweight: 42.9 kg) were assigned to either a control diet (CTR) or an identical diet supplemented (0.2%) with the plant extract mix (OC). No differences in the growth rate were observed. Glutathione peroxidase and glutathione reductase activities in the OC muscles (Longissimus lumborum) were higher than in CTR muscles. The lipid oxidation of meat was lower in the OC group. In the cooked meat samples, OC animals had the lowest L* and H° values and the highest a* values. The OC meat received higher scores for colour, taste and overall liking in both the blind and the labelled consumer tests.


Asunto(s)
Comportamiento del Consumidor , Fagaceae , Peroxidación de Lípido/efectos de los fármacos , Carne/análisis , Aceites Volátiles/farmacología , Origanum/química , Extractos Vegetales/farmacología , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Peso Corporal/efectos de los fármacos , Color , Culinaria , Dieta , Suplementos Dietéticos , Glutatión Peroxidasa/metabolismo , Glutatión Reductasa/metabolismo , Crecimiento/efectos de los fármacos , Humanos , Carne/normas , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Porcinos , Gusto , Madera
5.
Clin Endocrinol (Oxf) ; 80(5): 677-84, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-23594269

RESUMEN

OBJECTIVE: High sodium (HS) diet is associated with hypertension (HT) and insulin resistance (IR). We evaluated whether HS diet was associated with a dysregulation of cortisol production and metabolic syndrome (MetS). PATIENTS AND MEASUREMENTS: We recruited 370 adults (18-85 years, BMI 29·3 ± 4·4 kg/m(2) , 70% women, 72% HT, 61% MetS). HS diet (urinary sodium >150 mEq/day) was observed in 70% of subjects. We measured plasma hormones, lipid profile, urinary free cortisol (UFC) and cortisol tetrahydrometabolites (THM). RESULTS: Urinary sodium was correlated with UFC (r = +0·45, P < 0·001), cortisol THM (r = +0·41, P < 0·001) and inversely with adiponectin, HDL and aldosterone, after adjusting by age, gender and BMI. Subjects with high, compared with adequate sodium intake (50-149 mEq/day) had higher UFC (P < 0·001), THM (P < 0·001), HOMA-IR (P = 0·04), HT (81% vs 50%, P < 0·001), MetS (69% vs 41%, P < 0·001) and lower adiponectin (P = 0·003). A multivariate predictive model adjusted by confounders showed a high discriminative capacity for MetS (ROC curve 0·878) using four clinical variables: HS intake [OR = 5·6 (CI 2·3-15·3)], HOMA-IR [OR 1·7 (1·3-2·2)] cortisol THM [OR 1·2 (1·1-1·4)] and adiponectin [OR = 0·9 (0·8-0·9)], the latter had a protective effect. CONCLUSIONS: High sodium diet was associated with increased urinary cortisol and its metabolites. Also, HS diet was associated with HT, insulin resistance, dyslipidaemia and hypoadiponectinaemia, even when adjusting by confounding variables. Further, we observed that high salt intake, IR and higher cortisol metabolites, alone or combined in a clinical simple model, accurately predicted MetS status, suggesting an additive mechanism in obesity-related metabolic disorders.


Asunto(s)
Hidrocortisona/orina , Resistencia a la Insulina , Síndrome Metabólico/epidemiología , Sodio en la Dieta/efectos adversos , Adiponectina/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Aldosterona/orina , Glucemia/análisis , Índice de Masa Corporal , Estudios de Cohortes , Femenino , Glucocorticoides/metabolismo , Glucocorticoides/orina , Humanos , Hidrocortisona/metabolismo , Hipertensión/epidemiología , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Oportunidad Relativa , Sodio en la Dieta/orina , Adulto Joven
6.
Open Vet J ; 4(1): 1-3, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-26623330

RESUMEN

This report describes a case of spontaneous fibroblastic osteosarcoma in the humerus of a lion from a private park in Perugia, Italy. The tumor had an irregular, smooth, brown surface and a generally firm, rubbery consistence with gritty to hard areas interspersed. The mass was poorly vascularized with areas of necrosis at the periphery. The cut surface showed a multilobulated mass that had breached the humeral cortex, with periosteal production of reactive bone. The mass invaded the epiphysis, the synovial membrane, the joint capsule and ligaments. A mild hemorrhagic effusion appeared in the joint space. Clinical signs, gross and histopathologic findings are described in this rare case of a malignant bone tumor.

7.
J Hum Hypertens ; 27(3): 158-63, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22718050

RESUMEN

Primary aldosteronism (PA) is the most common endocrine form of hypertension and may carry an increased risk of atrial flutter or fibrillation (AFF). The primary goal of this multicentre cohort study is thus to prospectively establish the prevalence of PA in consecutive hypertensive patients referred for lone (non-valvular), paroxysmal or permanent AFF. Secondary objectives are to determine: (1) the predictors of AFF in patients with PA; (2) the rate of AFF recurrence at follow-up after specific treatment in the patients with PA; (3) the effect of AFF that can increase atrial natriuretic peptide via the atrial stretch and thereby blunt aldosterone secretion, on the aldosterone-to-renin ratio (ARR), and thus the case detection of PA; (4) the diagnostic accuracy of ARR based on plasma renin activity or on the measurement of active renin (DRA) for diagnosing PA in AFF patients. Case detection and subtyping of PA will be performed according to established criteria, including the 'four corners criteria' for diagnosing aldosterone-producing adenoma. Pharmacologic or direct current cardioversion will be undertaken whenever indicated following current guidelines. The hormonal values and ARR will be compared within patient between AFF and sinus rhythm. Organ damage, cardiovascular events and recurrence of AFF will also be assessed during follow-up in patients with PA.


Asunto(s)
Fibrilación Atrial/epidemiología , Aleteo Atrial/epidemiología , Hiperaldosteronismo/epidemiología , Proyectos de Investigación , Aldosterona/sangre , Antiarrítmicos/uso terapéutico , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/terapia , Aleteo Atrial/diagnóstico , Aleteo Atrial/terapia , Biomarcadores/sangre , Distribución de Chi-Cuadrado , Cardioversión Eléctrica , Europa (Continente) , Humanos , Hiperaldosteronismo/sangre , Hiperaldosteronismo/diagnóstico , Hipertensión/diagnóstico , Hipertensión/epidemiología , Prevalencia , Estudios Prospectivos , Calidad de Vida , Recurrencia , Renina/sangre , Factores de Tiempo , Resultado del Tratamiento
8.
J Thromb Haemost ; 8(3): 463-71, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20002542

RESUMEN

BACKGROUND: Apolipopoprotein C-III (apo C-III) plays a pivotal role in controlling plasma triglyceride (TG) and contributes to the atherogenic properties of TG-rich lipoproteins. OBJECTIVES: (i) To examine the predictive value of serum apo C-III for cardiovascular mortality in the setting of secondary prevention of coronary artery disease (CAD); and (ii) to evaluate possible associations between apolipoprotein levels and the thrombin generation assay, a global test to estimate plasma thrombogenic potential. METHODS AND RESULTS: A cohort of 633 patients with angiographically proven CAD was prospectively followed for a median follow-up of 57 months. The large majority of them (92%) underwent coronary (endovascular or surgical) revascularization. During the follow-up, 91 (14.3%) out of 633 patients died, with 64 events (10.1%) attributed to cardiovascular causes. After adjustment for all the other predictors of mortality during univariate analysis (i.e. age, statin therapy, myocardial infarction history, diabetes, hs-CRP and creatinine), elevated apo C-III levels (> or = 10.5 mg dL(-1)- the median value) significantly predicted both total and cardiovascular mortality (HR for total mortality 2.22 with 95% CI 1.16-4.24; HR for cardiovascular mortality 2.35 with 95% CI 1.19-4.62). In a subgroup of 225 subjects, apo C-III levels were significantly associated with endogenous thrombin potential in regression models (standardized beta coefficient = 0.207, P = 0.002). CONCLUSIONS: Basal concentrations of apo C-III levels > or = 10.5 mg dL(-1) in CAD patients independently predicted cardiovascular mortality during the subsequent 5-year period. Such concentrations were associated with an enhanced plasma endogenous thrombin generation, suggesting a complex interplay between TG-rich particles and the coagulation cascade as well as a new 'thrombogenetic' role for apo C-III.


Asunto(s)
Apolipoproteína C-III/sangre , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/mortalidad , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/mortalidad , Trombina/metabolismo , Anciano , Angioplastia Coronaria con Balón , Biomarcadores/sangre , Pruebas de Coagulación Sanguínea , Enfermedades Cardiovasculares/etiología , Distribución de Chi-Cuadrado , Angiografía Coronaria , Puente de Arteria Coronaria , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/terapia , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Prevención Secundaria , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento , Regulación hacia Arriba
10.
Clin Exp Med ; 7(4): 164-72, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18188530

RESUMEN

Triglyceride-rich lipoproteins contain both apolipoproteins E (ApoE) and C-III (ApoC-III), which show opposite functional properties. The relationships between the ApoE (epsilon2/epsilon3/epsilon4) gene polymorphism and ApoC-III/ApoE ratio has never been investigated. A large population (n=552) of cardiovascular patients, without diabetes and/or lipid-lowering therapy, with or without metabolic syndrome (MetSyn), was genotyped for epsilon2/epsilon3/epsilon4 polymorphism and their ApoCIII/ApoE ratio was evaluated. A second group of patients (n=76) with peripheral artery disease was also genotyped and their ApoC-III/ApoE ratios were measured in HDL and non-HDL fractions. Subjects with E2 had higher and E4 carriers lower TG,ApoE and ApoC-III levels, respectively. The ApoCIII/ ApoE ratio showed an opposite trend, gradually increasing from E2/E2 to E4/E4 subjects. MetSyn patients also had an elevated ApoC-III/ApoE ratio and E4 carriers were more frequent in MetSyn patients (OR 2.08 with a 95%CI 1.22-3.5). The distribution of ApoC-III/ApoE ratio was confirmed also in the second group, with lower values in E2/E3 and higher in E3/E4 subjects. Similar results were obtained for the concentrations measured in non-HDL fractions, but not in the HDL fractions. ApoE epsilon2/epsilon3/epsilon4 gene polymorphism is a determinant of the relative proportion of apolipoprotein C-III to E. Carriers of the unfavourable E4 allele present the highest ApoCIII/ApoE ratio and are twofold more frequent among individuals affected by MetSyn.


Asunto(s)
Apolipoproteína C-III/sangre , Apolipoproteína E2/genética , Apolipoproteína E3/genética , Apolipoproteínas E/sangre , Síndrome Metabólico/genética , Polimorfismo Genético , Adulto , Anciano , Femenino , Humanos , Masculino , Síndrome Metabólico/sangre , Persona de Mediana Edad
11.
Eur J Clin Invest ; 36(10): 698-704, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16968465

RESUMEN

BACKGROUND: To establish whether the frequent finding of a moderate-intermediate increase in plasma total homocysteine (tHcy) causes coronary artery disease (CAD), the authors evaluated the number of coexisting major traditional risk factors, as well as the major tHcy determinants, in patients with the same degree of CAD but different tHcy levels. MATERIALS AND METHODS: The authors studied 180 patients with CAD, who were divided into three groups according to tHcy levels: 60 patients with normal tHcy, 60 patients with moderate (15-30 micromol L(-1)) and 60 patients with intermediate hyperhomocysteinaemia (30-100 micromol L(-1)). The patient groups were matched for gender, age and number of affected coronary vessels. All patients were checked for the presence of traditional risk factors for CAD (i.e. hypertension, diabetes, hyperlipidaemia, smoking habit, familial history, obesity), as well as determinants of tHcy levels. The population was subdivided into those having, or not, a substantial burden of traditional risk factors (i.e. < 4 and > or = 4, respectively). RESULTS: There was a significant trend towards a reduced number of subjects within the group with > or = 4 risk factors across increasing tHcy levels (51.7%, 37.8%, 26%, for normal, moderate, intermediate tHcy, respectively, chi2 for linear-trend = 0.006). Folate and vitamin B12 concentrations, estimated glomerular filtration rate (GFR), MTHFR 677C > T polymorphism were the major determinants of tHcy in this population. CONCLUSIONS: In patients with the same degree of CAD, those with hyperhomocysteinaemia had a reduced burden of traditional risk factors as compared with those with normal tHcy levels. Hyperhomocysteinaemia was significantly associated with an emerging non-traditional risk factor such as lower GFR.


Asunto(s)
Enfermedad de la Arteria Coronaria/sangre , Homocisteína/sangre , Anciano , Enfermedad de la Arteria Coronaria/fisiopatología , Diabetes Mellitus/sangre , Diabetes Mellitus/epidemiología , Femenino , Tasa de Filtración Glomerular , Humanos , Hiperhomocisteinemia/sangre , Hiperlipidemias/sangre , Hiperlipidemias/epidemiología , Hipertensión/sangre , Hipertensión/epidemiología , Masculino , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Persona de Mediana Edad , Obesidad/sangre , Obesidad/epidemiología , Polimorfismo Genético , Factores de Riesgo , Complejo Vitamínico B/sangre
12.
Haemophilia ; 12(4): 448-51, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16834751

RESUMEN

We report the case of a patient with mild haemophilia A, due to a Tyr2105Cys mutation in exon 22 of the C1 domain, who developed a high-titre factor VIII inhibitor (maximum titre 1600 BU) with recurrent severe haemorrhages and fatal intracranial bleeding. Based on published data, it appears that although this mutation occurs rarely in patients with mild or moderate haemophilia A, it is frequently associated with the development of high-titre inhibitors.


Asunto(s)
Inhibidores de Factor de Coagulación Sanguínea/sangre , Factor VIII/genética , Hemofilia A/genética , Mutación , Hemorragia Cerebral/etiología , Exones , Factor VIII/antagonistas & inhibidores , Factor VIII/inmunología , Resultado Fatal , Hemofilia A/complicaciones , Humanos , Isoanticuerpos/sangre , Masculino , Persona de Mediana Edad , Factores de Riesgo
13.
Clin Exp Med ; 5(1): 20-30, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15928879

RESUMEN

The enzyme serum paraoxonase plays an important role in antioxidant defences and prevention of atherosclerosis. Metabolic syndrome (MS) is a clinical condition associated with increased oxidant stress and cardiovascular mortality. Two common polymorphisms of serum paraoxonase, PON1 Leu(55)Met and Gln(192)Arg, have been postulated to modulate the cardiovascular risk. We studied 915 subjects with angiographic documentation: 642 subjects with coronary atherosclerosis and 273 with normal coronary arteries. Two hundred and twenty-four subjects met the diagnostic criteria of MS. We found a significant interaction between MS and both the PON1 polymorphisms in determining the risk of coronary artery disease (P<0.05 by likelihood-ratio test). The 55Leu and the 192Arg alleles, associated with reduced protection against lipid peroxidation, were associated with coronary artery disease only in the MS subgroup. Subjects with MS and both 55Leu and 192Arg alleles had significantly increased risk (OR=9.38 with 95% CI=3.02-29.13 after adjustment by multiple logistic regression) as compared to subjects without MS and with 55Met/Met-192Gln/Gln genotype. No increased risk was found for subjects with MS and the 55Met/Met-192Gln/Gln genotype. This study highlights a potential example of genetic (paraoxonase polymorphisms)-clinical (MS) interaction influencing cardiovascular risk.


Asunto(s)
Arildialquilfosfatasa/genética , Enfermedad de la Arteria Coronaria/genética , Síndrome Metabólico/genética , Polimorfismo Genético , Anciano , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/enzimología , Femenino , Humanos , Masculino , Síndrome Metabólico/complicaciones , Síndrome Metabólico/enzimología , Persona de Mediana Edad , Factores de Riesgo
16.
Cell Mol Biol (Noisy-le-grand) ; 50(2): 179-85, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15095788

RESUMEN

In the present paper, we have reviewed the principal studies on red cell membrane abnormalities associated with neurodegenerative disorders. In the literature, two lines of investigation may be recognized: one based on the hypothesis of the presence of an oxidative environment responsible for red cell oxidative damage in Alzheimer's disease (AD), Alzheimer's dementia type (DAT) and Parkinson' disease (PD); the other one based on the identification of structural and/or functional abnormalities in red cell membrane band 3 and/or in red cell membrane lipid composition in "neuroacanthocytosis". In AD, DAT and PD patients, an increased red cell membrane lipid peroxidation suggests an increase red cell oxidative damages and precocious red cell aging. In "neuroacanthocytosis", grouping chorea-acanthocytosis, Mcleod syndrome and abetalipoproteinemia, the red cells are characterized by thorn or spur-like protrusions, known as "acanthocytes". The presence of circulating acanthocytes, characterized by abnormalities in red cell band 3 structure and/or function, is associated with increase levels of anti-band 3 antibodies which are physiologically produced against aged red cells and are known to mediate red cell removal from the peripheral circulation by macrophages. We have reviewed the mechanism(s) of the loss of red cell membrane stability and of the precocious red cell aging in neurodegenerative disorders.


Asunto(s)
Envejecimiento Eritrocítico , Enfermedades Neurodegenerativas/sangre , Corea/fisiopatología , Membrana Eritrocítica/patología , Eritrocitos Anormales/patología , Humanos , Modelos Biológicos , Enfermedades Neurodegenerativas/fisiopatología
17.
Eur J Clin Invest ; 34(1): 14-20, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14984433

RESUMEN

BACKGROUND: Increased oxidative stress is thought to play a role in the pathogenesis of the atherothrombotic process. Paraoxonases (PONs) are closely related antioxidant enzymes encoded by clustered genes on chromosome 7q. We evaluated three PON polymorphisms (PON1 Leu55Met and Gln192Arg; PON2 Ser311Cys) as possible risk factors for coronary atherosclerotic disease (CAD) and/or its main thrombotic complication, myocardial infarction (MI). MATERIALS AND METHODS: We studied 890 subjects with angiographic documentation of coronary vessels (272=CAD-free; 618=CAD). In the CAD group, 341 subjects had a previous MI. RESULTS: Frequencies of various genotypes were not significantly different between CAD-free subjects and the entire CAD population. In the latter group, there were more carriers of the PON2 311Cys variation among those who had suffered a MI than among those who had not (P<0.01 by chi2). The adjusted OR for MI among PON2 311Cys carriers was 1.5 (95%CI, 1.03-2.19). A gene-environmental interaction was found between PON2 Ser311Cys and smoking. Smoking by itself was associated with an increased MI risk. Among smokers, however, the MI risk was related to PON2 genotype: Cys/Cys homozygotes (OR=5.3; 95%CI, 1.7-16.4) and Ser/Cys heterozygotes (OR=2.1; 95%CI, 1.3-3.6) were at greater risk than Ser/Ser subjects (OR=1.2; 95%CI, 0.8-1.8). The PON2 polymorphism did not influence the MI risk among nonsmokers. CONCLUSIONS: In CAD subjects, a proportion of the risk of MI may be influenced by the interaction between smoking and a polymorphism in the antioxidant enzyme PON2.


Asunto(s)
Arildialquilfosfatasa/genética , Infarto del Miocardio/genética , Polimorfismo Genético/genética , Fumar/efectos adversos , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/enzimología , Enfermedad de la Arteria Coronaria/genética , Femenino , Genotipo , Humanos , Masculino , Malondialdehído/sangre , Persona de Mediana Edad , Infarto del Miocardio/sangre , Infarto del Miocardio/enzimología , Estrés Oxidativo/fisiología , Factores de Riesgo , Fumar/genética
19.
Clin Exp Med ; 2(1): 7-12, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12049191

RESUMEN

5, 10-Methylenetetrahydrofolate reductase (MTHFR) is a crucial enzyme in homocysteine/methionine metabolism. The most-studied C677T polymorphism in the MTHFR gene results in a thermolabile variant with reduced activity, and is associated with increased levels of total plasma homocysteine, a risk factor for coronary artery disease. A new mutation in the MTHFR gene (A1298C) has also been reported to lower enzyme activity. Whether A1298C is a risk factor for coronary artery disease, separately or in combination with C677T, and/or relative to total plasma homocysteine and folate status, is unclear to date. We evaluated this hypothesis in 470 angiographically characterized subjects, 302 with coronary artery disease, and 168 with normal coronary arteries. The frequency of the 1298C allele was 0.33 and that of combined heterozygosity 0.315. No difference was found in the frequency of the genotypes or when analyzed for combined heterozygosity between patients with coronary artery disease and normals. Independent of folate status, the 1298C allele was not associated with increased total plasma homocysteine. No additional effect of A1298C on total plasma homocysteine was observed in 148 combined heterozygotes compared with 98 heterozygotes for the C677T alone. These findings do not support a major role for the A1298C mutation in homocysteine metabolism and emphasize the hypothesis that MTHFR genotypes may interfere with coronary artery disease risk only when an unbalanced nutritional status leads to raised total plasma homocysteine levels.


Asunto(s)
Enfermedad de la Arteria Coronaria/enzimología , Ácido Fólico/sangre , Homocisteína/sangre , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/genética , Polimorfismo Genético , Anciano , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/genética , Femenino , Frecuencia de los Genes , Humanos , Italia , Masculino , Metilenotetrahidrofolato Reductasa (NADPH2) , Persona de Mediana Edad , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/metabolismo , Factores de Riesgo
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