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1.
Diabet Med ; 36(12): 1612-1620, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31456231

RESUMEN

AIMS: To analyse glucose-lowering drug utilization, focusing on the novel glucose-lowering drug groups dipeptidyl peptidase-4 inhibitors, glucagon-like peptide-1 receptor agonists and sodium-glucose co-transporter-2 inhibitors, and the financial burden they entail. METHODS: Crude reimbursed national drug utilization and expenditure data for the entire population of Hungary were obtained from the National Health Insurance Fund for the study period: 2008 to 2017. Data were analysed using the WHO's Anatomical Therapeutic Chemical Classification/defined daily dose system and were expressed in defined daily dose per 1000 inhabitants per day. RESULTS: Total glucose-lowering drug consumption in Hungary showed an 18% increase over the study period, reaching 74.7 defined daily doses per 1000 inhabitants per day, while novel glucose-lowering drug use increased to 11.7 defined daily doses per 1000 inhabitants per day (16% of total glucose-lowering drug use) by 2017. Dipeptidyl-peptidase 4 inhibitor consumption grew to 7.4 defined daily doses per 1000 inhabitants per day by 2017. The most widely used dipeptidyl-peptidase 4 inhibitor was sitagliptin. Glucagon-like peptide-1 receptor agonists were used the least, but by 2017 rose to 1.5 defined daily doses per 1000 inhabitants per day, led by liraglutide. Sodium-glucose co-transporter-2 inhibitors appeared in the utilization data in 2014 and their consumption, mainly empagliflozin, reached 2.8 defined daily doses per 1000 inhabitants per day by 2017. The total expenditure on glucose-lowering drugs increased 94% between 2008 and 2017, and the total cost of novel glucose-lowering drug utilization comprised 44% of the total glucose-lowering drug expenditure in 2017. CONCLUSIONS: Both the use of and the financial burden posed by novel glucose-lowering drugs in Hungary increased steadily between 2008 and 2017. This increase is expected to continue.


Asunto(s)
Diabetes Mellitus/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Costos de los Medicamentos/estadística & datos numéricos , Receptor del Péptido 1 Similar al Glucagón/agonistas , Humanos , Hungría , Hipoglucemiantes/economía , Estudios Retrospectivos , Fosfato de Sitagliptina/uso terapéutico
2.
Stroke ; 46(5): 1221-6, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25757900

RESUMEN

BACKGROUND AND PURPOSE: Growth of an intracranial aneurysm occurs in around 10% of patients at 2-year follow-up imaging and may be associated with aneurysm rupture. We investigated whether PHASES, a score providing absolute risks of aneurysm rupture based on 6 easily retrievable risk factors, also predicts aneurysm growth. METHODS: In a multicenter cohort of patients with unruptured intracranial aneurysms and follow-up imaging with computed tomography angiography or magnetic resonance angiography, we performed univariable and multivariable Cox regression analyses for the predictors of the PHASES score at baseline, with aneurysm growth as outcome. We calculated hazard ratios and corresponding 95% confidence intervals (CI), with the PHASES score as continuous variable and after division into quartiles. RESULTS: We included 557 patients with 734 unruptured aneurysms. Eighty-nine (12%) aneurysms in 87 patients showed growth during a median follow-up of 2.7 patient-years (range 0.5-10.8). Per point increase in PHASES score, hazard ratio for aneurysm growth was 1.32 (95% CI, 1.22-1.43). With the lowest quartile of the PHASES score (0-1) as reference, hazard ratios were for the second (PHASES 2-3) 1.07 (95% CI, 0.49-2.32), the third (PHASES 4) 2.29 (95% CI, 1.05-4.95), and the fourth quartile (PHASES 5-14) 2.85 (95% CI, 1.43-5.67). CONCLUSIONS: Higher PHASES scores were associated with an increased risk of aneurysm growth. Because higher PHASES scores also predict aneurysm rupture, our findings suggest that aneurysm growth can be used as surrogate outcome measure of aneurysm rupture in follow-up studies on risk prediction or interventions aimed to reduce the risk of rupture.


Asunto(s)
Aneurisma Intracraneal/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Aneurisma Roto/patología , Angiografía Cerebral , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Medición de Riesgo , Análisis de Supervivencia , Resultado del Tratamiento , Adulto Joven
3.
Stroke ; 46(1): 42-8, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25395411

RESUMEN

BACKGROUND AND PURPOSE: Unruptured intracranial aneurysms are frequently followed to monitor aneurysm growth. We studied the yield of follow-up imaging and analyzed risk factors for aneurysm growth. METHODS: We included patients with untreated, unruptured intracranial aneurysms and ≥6 months of follow-up imaging from 2 large prospectively collected databases. We assessed the proportion of patients with aneurysm growth and performed univariable and multivariable Cox regression analyses to calculate hazard ratios with corresponding 95% confidence intervals (CI) for clinical and radiological risk factors for aneurysm growth. We repeated these analyses for the subset of small (<7 mm) aneurysms. RESULTS: Fifty-seven (12%) of 468 aneurysms in 363 patients grew during a median follow-up of 2.1 years (total follow-up, 1372 patient-years). In multivariable analysis, hazard ratios for aneurysm growth were as follows: 1.1 (95% CI, 1.0-1.2) per each additional mm of initial aneurysm size; 2.7 (95% CI, 1.2-6.4) for dome > neck ratio; 2.1 (95% CI, 0.9-4.9) for location in the posterior circulation; and 2.0 (95% CI, 0.8-4.8) for multilobarity. In the subset of aneurysms <7 mm, 37 of 403 (9%) enlarged. In multivariable analysis, hazard ratios for aneurysm growth were 1.1 (95% CI, 0.8-1.5) per each additional mm of initial aneurysm size, 2.2 (95% CI, 1.0-4.8) for smoking, 2.9 (95% CI, 1.0-8.5) for multilobarity, 2.4 (95% CI, 1.0-5.8) for dome/neck ratio, and 2.0 (95% CI, 0.6-7.0) for location in the posterior circulation. CONCLUSIONS: Initial aneurysm size, dome/neck ratio, and multilobarity are risk factors for aneurysm growth. Cessation of smoking is pivotal because smoking is a modifiable risk factor for growth of small aneurysms.


Asunto(s)
Progresión de la Enfermedad , Hipertensión/epidemiología , Aneurisma Intracraneal/diagnóstico por imagen , Fumar/epidemiología , Angiografía Cerebral , Comorbilidad , Bases de Datos Factuales , Femenino , Humanos , Aneurisma Intracraneal/epidemiología , Aneurisma Intracraneal/patología , Angiografía por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estadística como Asunto , Tomografía Computarizada por Rayos X
4.
Stroke ; 45(5): 1299-303, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24652309

RESUMEN

BACKGROUND AND PURPOSE: Prediction of the risk of rupture of unruptured intracranial aneurysms is mainly based on aneurysm size and location. Previous studies identified features of aneurysm shape and flow angles as additional risk factors for aneurysm rupture, but these studies were at risk for confounding by patient-specific risk factors such as hypertension and age. In this study, we avoided this risk by comparing characteristics of ruptured and unruptured aneurysms in patients with both aneurysmal subarachnoid hemorrhage and multiple intracranial aneurysms. METHODS: We included patients with aneurysmal subarachnoid hemorrhage and multiple aneurysms who presented to our hospital between 2003 and 2013. We identified the ruptured aneurysm based on bleeding pattern on head computed tomography or surgical findings. Aneurysm characteristics (size, location, shape, aspect ratio [neck-to-dome length/neck-width], flow angles, sidewall or bifurcation type, and contact with bone) were evaluated on computed tomographic angiograms. We calculated odds ratios with 95% confidence intervals with conditional univariable logistic regression analysis. Analyses were repeated after adjustment for aneurysm size and location. RESULTS: The largest aneurysm had not ruptured in 36 (29%) of the 124 included patients with 302 aneurysms. Odds ratios for aspect ratio≥1.3 was 3.3 (95% confidence intervals [1.3-8.4]) and odds ratios for irregular shape was 3.0 (95% confidence intervals [1.0-8.8]), both after adjustment for aneurysm size and location. CONCLUSIONS: Aspect ratio≥1.3 and irregular shape are associated with aneurysm rupture independent of aneurysm size and location, and independent of patient characteristics. Additional studies need to assess to what extent these factors increase the risks of rupture of small aneurysms in absolute terms.


Asunto(s)
Aneurisma Roto/diagnóstico por imagen , Aneurisma Intracraneal/diagnóstico por imagen , Hemorragia Subaracnoidea/diagnóstico por imagen , Angiografía Cerebral , Humanos , Oportunidad Relativa , Tomografía Computarizada por Rayos X
5.
Lancet Neurol ; 13(4): 385-92, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24618352

RESUMEN

BACKGROUND: Individuals with two or more first-degree relatives who have had aneurysmal subarachnoid haemorrhage (aSAH) have an increased risk of aneurysms and aSAH. We investigated the yield of long-term serial screening for intracranial aneurysms in these individuals. METHODS: In a cohort study, we reviewed the results of screening of individuals with a positive family history of aSAH (two or more first-degree relatives who had had aSAH or unruptured intracranial aneurysms) done at the University Medical Centre Utrecht (Utrecht, Netherlands) between April 1, 1993, and April 1, 2013. Magnetic resonance angiography or CT angiography was done from age 16-18 years to 65-70 years. After a negative screen, we advised individuals to contact us after 5 years, but did not actively call them for repeated screening. We recorded familial history of ruptured and unruptured intracranial aneurysms, smoking history, hypertension, previous aneurysms, screening dates, and screening results. We identified risk factors for positive initial and follow-up screens with univariable and multivariable regression analysis. FINDINGS: We identified aneurysms in 51 (11%, 95% CI 9-14) of 458 individuals at first screening, in 21 (8%, 5-12) of 261 at second screening, in seven (5%, 2-11) of 128 at third screening, and three (5%, 1-14) of 63 at fourth screening. Five (3%, 95% CI 1-6) of 188 individuals without a history of aneurysms and with two negative screens had a de-novo aneurysm in a follow-up screen. Smoking (odds ratio 2·7, 95% CI 1·2-5·9), history of previous aneurysms (3·9, 1·2-12·7), and familial history of aneurysms (3·5, 1·6-8·1) were significant risk factors for aneurysms at first screening in the multivariable analysis. History of previous aneurysms was the only significant risk factor for aneurysms at follow-up screening (hazard ratio 4·5, 1·1-18·7). Aneurysms were identified in six (5%, 95% CI 2-10) of 129 individuals who were screened before age 30 years. One patient developed a de-novo aneurysm that ruptured 3 years after the last negative screen. INTERPRETATION: In individuals with a family history of aSAH, the yield of long-term screening is substantial even after more than 10 years of follow-up and two initial negative screens. We advocate long-term serial screening in these individuals, although the risk of aSAH within screening intervals is not eliminated. FUNDING: The Dutch Heart Foundation.


Asunto(s)
Aneurisma Intracraneal/diagnóstico , Tamizaje Masivo/métodos , Hemorragia Subaracnoidea/prevención & control , Adolescente , Adulto , Anciano , Angiografía Cerebral , Estudios de Cohortes , Femenino , Humanos , Aneurisma Intracraneal/prevención & control , Angiografía por Resonancia Magnética , Masculino , Persona de Mediana Edad , Factores de Tiempo
6.
Neurology ; 74(21): 1671-9, 2010 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-20498435

RESUMEN

OBJECTIVE: Individuals with a family history of subarachnoid hemorrhage (SAH), defined as 2 or more affected first-degree relatives, have an increased risk of aneurysm formation and rupture. Screening such individuals for intracranial aneurysms is advocated, but its effectiveness and cost-effectiveness are unknown, as are the optimal age ranges and interval for screening. METHODS: With a Markov model and Monte Carlo simulations we compared screening with no screening in individuals with a family history of SAH. We varied age ranges (starting screening at 20, 30, or 40 years old, ending screening at 60, 70, or 80 years old) and screening intervals (2-, 3-, 5-, 7-, 10-, and 15-year interval), and analyzed the impact in costs and quality-adjusted life years (QALY). RESULTS: Screening individuals with a family history of SAH is cost-effective. The strategy with the lowest costs per QALY was to screen only twice, at 40 and 55 years old. Sequentially lengthening the screening period and decreasing the screening interval yielded additional health benefits at acceptable costs up to screening from age 20 to 80 every 7 years. More frequent screening within this age range still provided extra QALYs, with an incremental cost-effectiveness ratio more favorable than 26,308/QALY ($38,410/QALY). CONCLUSION: This study provides evidence for recommendations to screen individuals with 2 or more first-degree relatives with subarachnoid hemorrhage. The optimal screening strategy according to our model is screening from age 20 until 80 every 7 years given a cost-effectiveness threshold of 20,000/quality-adjusted life year (QALY) ($29,200/QALY).


Asunto(s)
Análisis Costo-Beneficio , Salud de la Familia , Aneurisma Intracraneal/economía , Años de Vida Ajustados por Calidad de Vida , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Análisis Costo-Beneficio/economía , Femenino , Humanos , Aneurisma Intracraneal/diagnóstico , Masculino , Cadenas de Markov , Tamizaje Masivo/métodos , Persona de Mediana Edad , Método de Montecarlo , Adulto Joven
7.
J Neurol Neurosurg Psychiatry ; 81(1): 116-8, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20019231

RESUMEN

BACKGROUND AND PURPOSE: Several risk factors for aneurysmal subarachnoid haemorrhage have been identified but it is not known whether some sites of aneurysms are linked to a specific risk factor. In a series of patients with aneurysmal subarachnoid haemorrhage, we compared risk factors according to the site of the ruptured aneurysm at the circle of Willis. METHODS: From our prospectively collected database of patients with aneurysmal subarachnoid haemorrhage admitted to our hospital between 2003 and 2007, we retrieved 304 patients with saccular aneurysms on the anterior communicating artery, middle cerebral artery, posterior communicating artery, basilar artery and vertebral artery. Risk factors (age, gender, smoking, no or excessive alcohol intake, hypertension and familial preponderance) were assessed per aneurysm location and compared with the anterior communicating artery as reference. We calculated odds ratios (ORs) and corresponding 95% CI. RESULTS: In comparison with aneurysms at the anterior communicating artery, those at the middle cerebral artery were less associated with age >55 years (OR 0.4; 95% CI 0.2 to 0.8), those at the posterior communicating artery were less associated with male gender (OR 0.4; 95% CI 0.2 to 0.9) and those at the basilar artery were more associated with no alcohol consumption (OR 5.8; 95% CI 1.1 to 29.9). CONCLUSION: Risk factors differ according to the site of aneurysm. This heterogeneity should be kept in mind in studies on the aetiology of aneurysms, such as genetic studies.


Asunto(s)
Aneurisma Intracraneal/etiología , Factores de Edad , Consumo de Bebidas Alcohólicas/efectos adversos , Intervalos de Confianza , Familia , Femenino , Humanos , Hipertensión/complicaciones , Aneurisma Intracraneal/genética , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Estudios Prospectivos , Factores de Riesgo , Factores Sexuales , Fumar/efectos adversos , Hemorragia Subaracnoidea/etiología , Hemorragia Subaracnoidea/genética
8.
Stroke ; 40(6): 2226-8, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19372449

RESUMEN

BACKGROUND AND PURPOSE: Anosmia occurs frequently in patients with subarachnoid hemorrhage (SAH) from a ruptured aneurysm treated with clipping. We analyzed prevalence, prognosis, and potential risk factors for anosmia after coiling for SAH. METHODS: We interviewed all patients who resumed independent living after SAH treated with coiling between 1997 and 2007. We assessed by means of logistic regression analyses whether risk of anosmia was influenced by site of the ruptured aneurysm, neurological condition on admission, amount of extravasated blood, hydrocephalus, and treatment for hydrocephalus. RESULTS: Of 197 patients, 35 (18%; 95%CI:12 to 23) experienced anosmia. Anosmia had improved in 23 (66%) of them; in 20 the recovery had been complete after a median period of 6 weeks (SD +/-6.5). Intraventricular hemorrhage was a risk factor for anosmia (OR 2.4; 95%CI:1.0 to 5.9). Anterior aneurysm location (OR 1.1; 95%CI:0.5 to 2.3) and high amount of extravasated blood (OR 0.9; 95%CI:0.4 to 2.1) were not related to anosmia. CONCLUSIONS: Anosmia occurs after coiling in 1 of every 6 SAH patients, but has a good prognosis in most patients. The cause of anosmia after coiling for ruptured aneurysms remains elusive; severity of the initial hemorrhage or long lasting hydrocephalus may be contributing factors.


Asunto(s)
Aneurisma Roto/psicología , Aneurisma Roto/cirugía , Aneurisma Intracraneal/psicología , Aneurisma Intracraneal/cirugía , Procedimientos Neuroquirúrgicos , Trastornos del Olfato/etiología , Trastornos del Olfato/psicología , Complicaciones Posoperatorias/psicología , Factores de Edad , Anciano , Enfermedades de las Arterias Carótidas/patología , Angiografía Cerebral , Enfermedades Arteriales Cerebrales/patología , Femenino , Humanos , Hidrocefalia/complicaciones , Hidrocefalia/terapia , Masculino , Persona de Mediana Edad , Trastornos del Olfato/epidemiología , Complicaciones Posoperatorias/etiología , Pronóstico , Factores de Riesgo , Hemorragia Subaracnoidea/complicaciones , Instrumentos Quirúrgicos , Encuestas y Cuestionarios , Tomografía Computarizada por Rayos X
9.
Brain ; 131(Pt 10): 2662-5, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18819992

RESUMEN

Relatives of patients with aneurysmal subarachnoid haemorrhage (SAH) have an increased risk of this type of stroke. In a population-based study, we analysed individualized risks of SAH according to the number of affected first-degree relatives. We retrieved all patients diagnosed with SAH in 2001-05 from the Swedish Inpatient Register. For each of the 5,282 patients, we identified five controls (n = 26,402) through the nationwide Register of Total Population. Through the Multi-generation Register, we retrieved all first-degree relatives for patients and controls and checked whether these 130,373 relatives had been diagnosed with SAH. By means of conditional logistic regression, we calculated odds ratios with corresponding 95% confidence intervals (95% CI) for the risk of SAH according to the number of affected relatives, and to the gender, age and type of kinship of the patient and affected relative. The odds ratio of SAH for individuals with one affected first-degree relative was 2.15 (95% CI 1.77-2.59). For individuals with two affected first-degree relatives, the odds ratio was 51.0 (95% CI 8.56-1117). Gender, age and type of kinship did not influence the risk for individuals with one or more affected relatives. The risk of SAH is slightly increased in the cases with one, but strongly increased in cases with two or more affected first-degree relatives. The latter strongly increased risk corresponds to a considerable absolute life-time risk of SAH and underscores the need to consider screening for aneurysms in these individuals.


Asunto(s)
Familia , Hemorragia Subaracnoidea/genética , Adolescente , Adulto , Distribución por Edad , Anciano , Estudios de Casos y Controles , Censos , Intervalos de Confianza , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Medición de Riesgo/métodos , Distribución por Sexo , Suecia , Adulto Joven
10.
Neurology ; 70(9): 700-5, 2008 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-18299521

RESUMEN

BACKGROUND: The reasons for development of intracranial aneurysms are unknown; hemodynamic factors may play an important role in this process. We performed a cohort study to further elicit the role of intracranial arterial geometry. METHODS: We compared the original CTA/MRA of the circle of Willis of 26 patients who developed an aneurysm during follow-up with those of 78 controls with no aneurysm development who were matched for gender, age, and period of follow-up. We assessed hypoplasia of the arteries of the circle of Willis and measured bifurcation angles within and beyond the circle of Willis on three-dimensional CTA/MRA. Bifurcation angles were classified in tertiles for analysis. We used Student t test for comparison of bifurcation angles and calculated OR with corresponding 95% CI for presence of hypoplasia and bifurcation angles in tertiles. RESULTS: A hypoplastic branch was found in 5 of 7 (71%) sites with aneurysm development and in 6 of 21 corresponding sites (29%) without aneurysm development (OR 6; 95%CI 0.9 to 42). The branch angle was sharp (lowest tertile) in 10 of 14 (71%) sites with aneurysm development and in 8 of 42 (19%) sites without aneurysm development (OR 11.3; 95% CI 2.0 to 64). CONCLUSIONS: Bifurcations with a hypoplastic branch and bifurcations with sharper bifurcation angles are risk factors for development of aneurysms. Analysis of the geometry of intracranial arteries might be helpful in detecting persons with increased risk for developing aneurysms.


Asunto(s)
Angiografía Cerebral , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Aneurisma Intracraneal/diagnóstico , Angiografía por Resonancia Magnética , Tomografía Computarizada por Rayos X , Círculo Arterial Cerebral , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Malformaciones Arteriovenosas Intracraneales/diagnóstico , Masculino , Persona de Mediana Edad , Factores de Riesgo , Hemorragia Subaracnoidea/diagnóstico
11.
Chem Phys Lipids ; 150(2): 186-203, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17900550

RESUMEN

Copper-induced peroxidation of liposomal palmitoyllinoleoyl-phosphatidylcholine (PLPC) is inhibited by alpha-tocopherol at micromolar concentrations. In our previous study we found that when the liposomes contain phosphatidylserine (PS), nanomolar concentrations of Toc were sufficient to inhibit peroxidation. In an attempt to gain understanding of the origin of this extreme antioxidative potency, we tested the antioxidative potency of 36 additional antioxidants and the dependence of their potency on the presence of PS in the liposomes. The results of these studies reveal that only 11 of the tested antioxidants possess similar antioxidative potency to that of Toc. These include trolox, butylated hydroxytoluene (BHT), curcumin, nordihydroguaiaretic acid (NDGA), diethylstilbestrol (DES), 2 of the 13 tested flavonoids (luteolin and 7,3',4'-trihydroxyflavone; T-414), alpha-naphthol, 1,5-, 1,6- and 1,7-dihydroxynaphthalenes (DHNs). Propyl gallate (PG), methyl syringate, rosmarinic acid, resveratrol, other flavonoids, as well as beta-naphthol, 1,2-, 1,3-, 1,4-, 2,3-, 2,6-, and 2,7-DHNs were either moderately antioxidative or pro-oxidative. For liposomes made of PLPC (250 microM) and PS (25 microM) the "lag" preceding copper-induced peroxidation (5 microM copper) was doubled upon addition of 30-130nM of the "super-active" antioxidants. We propose that the mechanism responsible for the extreme antioxidative potency against copper-induced peroxidation in PS-containing liposomes involves replenishment of the antioxidant in a ternary PS-copper-antioxidant complex. Based on structure-activity relationship of the 37 tested antioxidants, the "super-antioxidative potency" is attributed to the recycling of relatively stable semiquinone or semiquinone-like radicals.


Asunto(s)
Antioxidantes/farmacología , Cobre/farmacología , Liposomas/química , Fosfatidilserinas/química , Antioxidantes/química , Antioxidantes/metabolismo , Hidroxitolueno Butilado/farmacología , Cromanos/farmacología , Cinamatos/química , Curcumina/química , Curcumina/farmacología , Depsidos/química , Dietilestilbestrol/farmacología , Flavonoides/farmacología , Liposomas/metabolismo , Luteolina/farmacología , Masoprocol/farmacología , Nanotecnología/métodos , Naftoles/farmacología , Fenol/química , Fosfatidilcolinas/química , Relación Estructura-Actividad , Ácido Rosmarínico
12.
Chem Phys Lipids ; 146(1): 43-53, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17241622

RESUMEN

Lipid peroxidation is believed to play an important role in the pathogenesis of many diseases. Much research has therefore been devoted to peroxidation of different lipids in biomembranes and in model systems (liposomes) of different compositions. Yet, in spite of the relative simplicity of the liposomes, the existing literature is insufficient to reach definite conclusions regarding basic questions including the susceptibility of cholesterol to oxidation, its effect on the peroxidation of polyunsaturated phospholipids such as palmitoyllinoleoylphosphatidylcholine (PLPC) and how cholesterol influences the effect of water-soluble antioxidants such as urate on the peroxidation. The aim of the present study was to clarify these issues. Its major findings are that: (i) AAPH-induced peroxidation of cholesterol is slow and independent of the peroxidation of PLPC. In turn, AAPH-induced peroxidation of PLPC is not affected by cholesterol, independent of the presence of urate in the system. (ii) Cholesterol is not susceptible to copper-induced oxidation, but its inclusion in PLPC liposomes affects the peroxidation of PLPC, slowing down the initial stage of oxidation but promoting later stages. (iii) Addition of urate accelerates copper-induced peroxidation of PLPC in the absence of cholesterol, whereas in cholesterol-containing liposomes it inhibits PLPC oxidation. We attribute the complexity of the observed kinetics to the known cholesterol-induced rigidization of liquid crystalline bilayers.


Asunto(s)
Colesterol/química , Peroxidación de Lípido , Liposomas/química , Fosfolípidos/química , Amidinas/química , Membrana Dobles de Lípidos , Oxidación-Reducción , Fosfatidilcolinas/química
13.
Reprod Fertil Dev ; 18(4): 433-7, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16737636

RESUMEN

The present study was conducted in an Assaf flock in which the FecB (Booroola) mutation was segregated to determine whether the FecB mutation affects birthweight and the pre- and post-weaning growth rate of ewe lambs, as well as the mature bodyweight of ewes. Significant differences (P = 0.01) in birthweight (mean +/- s.e.m.) were found between BB ewe lambs (4.03 +/- 0.08 kg) and B+ and ++ ewe lambs (4.16 +/- 0.04 and 4.32 +/- 0.07 kg, respectively), which themselves did not differ significantly (P > 0.05). An FecB-associated maternal effect on the birthweight of ewe lambs was also detected, with the birthweight of lambs born to BB mothers (3.93 +/- 0.08 kg) being significantly (P < 0.0001) different from the birthweight of lambs born to B+ and ++ mothers (4.26 +/- 0.04 and 4.33 +/- 0.07 kg, respectively), which did not differ significantly. The genotypes of the lambs did not affect their preweaning growth rate. However, the post-weaning growth rate of ewe BB lambs (274 +/- 5 g day(-1)) was significantly (P = 0.05) different from the similar (P > 0.05) post-weaning growth rates of B+ and ++ lambs (284 +/- 3 and 290 +/- 4 g day(-1), respectively). The genotype at the FecB locus also affected the mature bodyweight of ewes, with that of BB ewes (67.3 +/- 1.4 kg) being significantly (P < 0.001) different from the similar mature bodyweight of B+ and ++ ewes (70.8 +/- 1.1 and 70.1 +/- 1.7 kg, respectively).


Asunto(s)
Peso al Nacer/genética , Mutación , Ovinos/crecimiento & desarrollo , Ovinos/genética , Destete , Animales , Peso Corporal/genética , Cruzamientos Genéticos , Femenino , Genotipo , Aumento de Peso/genética
14.
Domest Anim Endocrinol ; 30(2): 135-43, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16024214

RESUMEN

The study of gene function in vivo is considered one of the top achievements of modern biology, inasmuch as it provides tools to study gene function in the context of the whole animal. In chickens, techniques of DNA-mediated gene transfer are less advanced than in other animal or livestock models, and remain a significant challenge. The study presented here is the first to show that a hydrodynamics-based gene-transfer technique, originally developed for naked DNA transfer in mice, can be applied to chickens. Rapid injection of naked plasmids containing expression cassettes into the jugular vein of 6- to 10-day-old chicks resulted in specific expression of the transgenes. A CMV promoter-driven luciferase reporter gene was expressed at significant levels in the liver during the first 3 days post-injection with lower levels also detected in the kidney. Significantly, all injected birds showed detectable levels of luciferase expression. Similarly, injection of a plasmid containing the secreted human coagulation factor IX (hFIX) gene under the control of human alpha-1-anti-trypsin promoter resulted in detectable levels of the hFIX in the plasma during the first 2 days post-injection. The method described herein has the potential for a quick and simple route for gain and loss-of function experiments in chicken liver and kidney, as well as for studying systemic effects of secreted proteins and hormones.


Asunto(s)
Pollos/genética , Técnicas de Transferencia de Gen/veterinaria , Plásmidos/genética , Animales , Animales Modificados Genéticamente , Ensayo de Inmunoadsorción Enzimática/veterinaria , Factor IX/genética , Luciferasas/genética , Luciferasas/metabolismo , Plásmidos/administración & dosificación
15.
Hum Reprod ; 20(12): 3554-9, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16174650

RESUMEN

BACKGROUND: Successful cryopreservation of a whole ovary may provide a solution for women with premature ovarian failure. The aim of this study was to evaluate the function of cryopreserved whole sheep ovaries both in vitro and in vivo. METHODS: Transplantation of frozen-thawed intact ovaries was performed on eight sheep by artery and vein anastomosis to the contralateral ovarian artery and vein. The remaining ovary was removed. Oocyte aspiration was performed 1 and 4 months post-transplantation. Serum progesterone levels were measured after 24 and 36 months. Magnetic resonance imaging (MRI) was carried out 12 months after transplantation. RESULTS: Progesterone activity was detected in three sheep from 24 to 36 months post-transplantation. Oocyte retrieval was successful in two sheep and parthenogenic activation has resulted in embryonic development up to the 8-cell stage. MRI revealed an intact ovary with small follicles and intact blood vessels. CONCLUSIONS: Whole ovaries, and the follicles and blood vessels they contain, are able to survive cryopreservation. In addition, MRI has shown that blood vessels were intact and that normal blood flow had resumed to the transplant. We conclude that immediate and long-term hormonal restoration and normal ovulation is possible after cryopreservation and transplantation of whole ovaries in sheep.


Asunto(s)
Criopreservación/métodos , Desarrollo Embrionario , Oocitos/patología , Folículo Ovárico/patología , Ovario/trasplante , Recolección de Tejidos y Órganos/métodos , Animales , Femenino , Inmunohistoquímica , Imagen por Resonancia Magnética , Oocitos/metabolismo , Ovario/irrigación sanguínea , Ovario/patología , Progesterona/sangre , Ovinos , Factores de Tiempo
16.
Rev. biol. trop ; 52(4): 931-936, dic. 2004. tab
Artículo en Inglés | LILACS | ID: lil-450788

RESUMEN

A population of 216 specimens of Stenocereus eichlamii (Cactaceae,Subfamily Cereoideae) was surveyed for Triatoma ryckmani (vector of Chagas disease)in a one hectare plot of semiarid habitat in Guatemala. Out of 44 plants that had dead and dry sections,24 plants had a total of 103 specimens of T.ryckmani .In comparison with other areas of Guatemala,T.ryckmani is well established in the semiarid ecosystem (Infestation index 54.5,density =2.3 and crowding index 4.3).The insects were mainly found (52.4%)in the dead portions of S.eichlamii 2.0 to 3.2 m above the ground (X2 =26.0,P<0.00001),followed by dry cactus sections between 3.2 and 5.0 m (35.9%).They were less frequent 0.2 to 2.0 m above the ground.A considerable proportion (75.7%)had no aparent blood in their digestive systems.To determine the presence of flagellates,43 of the bugs were dissected,but none were found.This is the first report on T.ryckmani population dynamics in this habitat


En Guatemala,en una hectárea de la región semiárida,se encontraron 216 cactus de Stenocereus eichlamii (Cactaceae),44 de ellos tenían alguna parte del tallo en condiciones secas.103 Triatoma ryckmani fueron halladas en 24 de esos 44 S.eichlamii .Una comparación de los índices entomológicos con otros vectores domiciliares de la enfermedad de Chagas en Guatemala,da la idea que T. ryckmani está bien establecida en el ecosistema semiárido (índice de infestación de 54.5,índice de densidad de 2.3 e índice de hacinamiento de 4.3).Los triatominos fueron hallados preferentemente en las partes muertas de S.eichlamii entre 2.0 a 3.2 m sobre el nivel del suelo (52.4%de triatominos colectados,X ²=26.0,p<0.00001),el siguiente entre 3.2 a 5.0 m (35.9%)y finalmente 0.2 a 2.0 m (11.6%). El 75.7 %estaba en condiciones de ayuno y 24.3 %estaban llenas de sangre.Para determinar la presencia de flagelados,43 T.ryckmani fueron disectadas, (primera evaluación de parasitemia en esta especie).Ningún flagelado fue hallado en estos triatominos.Este es el primer reporte de la dinámica poblacional de T.ryckmani en su hábitat silvestre


Asunto(s)
Humanos , Animales , Cactaceae/parasitología , Enfermedad de Chagas/transmisión , Insectos Vectores/crecimiento & desarrollo , Triatoma/crecimiento & desarrollo , Trypanosoma cruzi/crecimiento & desarrollo , Ambiente , Conducta Alimentaria , Guatemala , Vivienda , Enfermedades de las Plantas/parasitología , Densidad de Población
17.
J Dairy Sci ; 85(6): 1398-405, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12146470

RESUMEN

Conception in dairy cows during autumn remains low even after summer temperatures decline. This is possibly a residual effect of heat stress on oocyte quality. Lactating Holsteins previously heat-stressed during summer were used in two experiments (n = 8 and 16 cows) in autumn to examine hormonal strategies for improving quality of oocytes. Follicles (3 to 8 mm in diameter) were aspirated by the ovum pick-up procedure on d 4 of two consecutive estrous cycles of treated and control cows. Oocytes were classified morphologically, matured in vitro, chemically activated, and cultured for 8 d. In Experiment 1, FSH (2 x 200 mg, at a 12-h interval) was injected on d 5 and 12 of cycle 1 (treated cycle). Before FSH, the percentage of good quality oocytes (grade I) and the cleavage rate averaged 52 and 24%, respectively, in both groups. During the FSH-treated cycle, more 6- to 9-mm follicles were observed. In the subsequent cycle, rates of grade I oocytes and cleavage were significantly higher in FSH-treated than in control cows (89 vs. 51% and 85 vs. 31%, respectively). In Experiment 2, recombinant bovine somatotropin (bST, 500 mg) was injected on d 4 and 18 of the treated cycle. The bST treatment increased the number of 3- to 5-mm follicles. Before bST, grade I (39%) and cleaved oocytes (40%), were similar across treatment groups. In the subsequent cycle, the percentage of grade I oocytes was significantly higher in treated than in control cows (72 vs. 26%), but cleavage rates were similar. Neither FSH or bST improved blastocyst formation, and regardless of treatment, few blastocysts were formed. Treatment with bST improved oocyte morphology, whereas FSH improved both oocyte morphology and cleavage rates during autumn following summer heat stress.


Asunto(s)
Bovinos/fisiología , Fertilidad/fisiología , Hormona Folículo Estimulante/farmacología , Hormona del Crecimiento/farmacología , Calor/efectos adversos , Oocitos/fisiología , Animales , Enfermedades de los Bovinos/tratamiento farmacológico , Enfermedades de los Bovinos/fisiopatología , Desarrollo Embrionario y Fetal , Femenino , Fertilidad/efectos de los fármacos , Hormona Folículo Estimulante/sangre , Trastornos de Estrés por Calor/tratamiento farmacológico , Trastornos de Estrés por Calor/fisiopatología , Trastornos de Estrés por Calor/veterinaria , Oocitos/efectos de los fármacos , Folículo Ovárico/citología , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/fisiología , Distribución Aleatoria , Estaciones del Año , Succión , Factores de Tiempo
18.
Reproduction ; 122(5): 737-44, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11690534

RESUMEN

The fertility of dairy cows decreases during the summer and remains low during the cooler autumn although the animals are no longer under heat stress. The aim of this study was to characterize a delayed effect of summer heat stress on oocyte quality in the autumn and to improve oocyte quality by enhanced removal of follicles damaged during the previous summer. Lactating cows (n = 16) were subjected to heat stress during the summer. In autumn, ovarian follicles (3-7 mm in diameter) were aspirated by an ultrasound-guided procedure during four consecutive oestrous cycles. Follicles were aspirated from control cows on day 4 and from treated cows on days 4, 7, 11 and 15 of each oestrous cycle. All cows received PGF(2alpha) and GnRH injections on days 19 and 21, respectively, and maintained cyclicity, as indicated by plasma progesterone concentrations. On day 4 of each cycle, the oocytes recovered were examined morphologically, matured and activated in vitro, and cultured for 8 days. In cycle 1 (early October) both groups showed low percentages of grade 1 oocytes, cleavage, four- and eight-cell embryos, morulae and parthenogenetic blastocysts. Subsequently, the number of grade 1 oocytes increased earlier (cycle 2) in treated than in control cows (cycle 3; P < 0.05). The cleavage rate in the control group remained relatively low throughout (32-58%), whereas in the treated group it increased from 40% (cycle 1) to 75% (cycles 3 and 4; P < 0.05). The number at each stage of embryo development increased slightly but remained low throughout in the control group, whereas in the treated group significant (P < 0.05) increases of all stages were observed in cycles 3 and 4. The results show a delayed effect of summer heat stress on oocyte quality and embryo development in the autumn. Enhanced removal of the impaired cohort of follicles led to earlier emergence of healthy follicles and high quality oocytes in the autumn.


Asunto(s)
Calor/efectos adversos , Oocitos/fisiología , Folículo Ovárico , Estaciones del Año , Animales , Bovinos , Células Cultivadas , Fase de Segmentación del Huevo , Dinoprost/farmacología , Desarrollo Embrionario y Fetal , Femenino , Hormona Liberadora de Gonadotropina/farmacología , Succión
19.
Anim Reprod Sci ; 64(3-4): 181-97, 2000 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-11121895

RESUMEN

Insulin and glucose may be limiting factors for ovarian function in dairy cows genetically selected for high milk yield. The effects of nutrition on the intrafollicular content of insulin and glucose were investigated in Israeli Holstein dairy cattle fed a basic total mixed ration and producing 34-39kg of milk daily. In experiment 1, carried out in 11 oestrus-synchronised cows, little variation in insulin concentration was found in plasma sampled during the luteal phase, but high variation was found in plasma sampled during the follicular phase. Therefore, in order to prevent confounding the effects of diet and of phase in cycle in the following experiments, experimental diets were fed during the luteal phase of synchronised oestrus cycles. In experiment 2, designed as Latin-Square, six cows received sequentially diets containing 17.1 (control) or 19.7% of crude protein, using two sources of supplementary protein, i.e. soyabean meal (SBM) and corn gluten meal (CGM), differing in ruminal degradability and leucine content. When dry matter intake was used as covariant, plasma insulin on day 16 was 29.5 and 26.4% higher in cows fed diets containing SBM and CGM than in the control (P<0.05). In experiment 3, 17 cows were individually fed the basic diet and then switched to isoenergetic diets containing SBM (n=5), CGM (n=6) or corn grain (CG, n=6) given from day 10 to 16 of the synchronised oestrus cycle. On the eve of day 16, and in the morning of day 17, they were administered PGF(2alpha) and the content of 26 largest follicles was aspirated by using the transvaginal ovum pick-up technique. Follicles were sorted into two classes (preovulatory and subordinate) according to oestradiol concentration and the progesterone:oestradiol ratio in follicular fluid (FF). Higher concentrations of insulin (0.282 versus 0.127ng/ml, P<0.0001) and of glucose (0.614 versus 0.386g/l, P<0.002), were found in FF from preovulatory follicles. The insulin concentration in the FF of cows fed the CG diet was 26% higher than in their counterparts fed CGM (P<0.04), SBM being intermediate. Dietary effects did not reach significance in subordinate follicles. The finding that preovulatory follicular status is associated with increased intrafollicular insulin and glucose suggests that insulin is involved in follicular maturation. The nutritional effect on intrafollicular glucose and insulin may have practical implications to optimise feeding in dairy cows during phases of the oestrus cycle.


Asunto(s)
Alimentación Animal , Glucosa/metabolismo , Insulina/metabolismo , Folículo Ovárico/fisiología , Animales , Glucemia/metabolismo , Bovinos , Industria Lechera , Ciclo Estral/sangre , Sincronización del Estro , Femenino , Insulina/sangre , Lactancia , Leche/metabolismo , Fenómenos Fisiológicos de la Nutrición , Folículo Ovárico/diagnóstico por imagen , Ovario/diagnóstico por imagen , Ovario/fisiología , Progesterona/metabolismo , Ultrasonografía
20.
J Dairy Sci ; 82(11): 2358-68, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10575602

RESUMEN

The effect of fat and bovine somatotropin (bST) on preovulatory follicular hormones and lipids was evaluated by feeding cows for 150 d from parturition a control diet, a control diet plus 0.55 kg/d of calcium soaps of fatty acids, or a control diet with 500 mg of bST injected every 14 d. Fourteen days after a synchronized or natural estrus, cows were injected with a PGF2 alpha analogue; 48 h later, follicular fluid from all ovarian follicles > 8 mm was aspirated. Cows fed fat or injected with bST produced more milk and milk solids than did control cows, and cows on the bST treatment lost more body condition after calving than did cows on the other treatments. Both treatments changed the proportion of estradiol-active follicles (> 400 ng of estradiol/ml of follicular fluid) and the correlation between follicular fluid estradiol concentration and the total number large follicles per cow. In follicles aspirated between 60 and 90 DIM the percentage of estradiol-active follicles was 67, 40, and 0 for cows on the control, calcium soaps of fatty acids, and bST treatments, respectively. After 90 DIM, no differences existed between treatments in the percentage of estradiol-active follicles. Estradiol concentration in follicular fluid was correlated with DIM at follicle aspiration (r = 0.51). The proportion of oleic acid in free fatty acids in plasma at 50 DIM was lower in control cows and was lower in follicular fluid of estradiol-active follicles. Both calcium soaps of fatty acids and bST had a considerable effect on follicular development and activity and the composition of fatty acids in follicles.


Asunto(s)
Calcio/farmacología , Bovinos/fisiología , Ácidos Grasos/farmacología , Hormona del Crecimiento/farmacología , Metabolismo de los Lípidos , Folículo Ovárico/fisiología , Androstenodiona/metabolismo , Animales , Composición Corporal , Peso Corporal , Estradiol/metabolismo , Ácidos Grasos/metabolismo , Ácidos Grasos no Esterificados/sangre , Femenino , Líquido Folicular/metabolismo , Lactancia/fisiología , Lípidos/sangre , Ovulación , Progesterona/metabolismo , Jabones
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