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1.
Langmuir ; 32(27): 6794-805, 2016 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-27281114

RESUMEN

Understanding calcium silicate hydrates (CSHs) is of paramount importance for understanding the behavior of cement materials because they control most of the properties of these man-made materials. The atomic scale water content and structure have a major influence on their properties, as is analogous with clay minerals, and we should assess these. Here, we used a multiple analytical approach to quantify water distribution in CSH samples and to determine the relative proportions of water sorbed on external and internal (interlayer) surfaces. Water vapor isotherms were used to explain the water distribution in the CSH microstructure. As with many layered compounds, CSHs have external and internal (interlayer) surfaces displaying multilayer adsorption of water molecules on external surfaces owing to the hydrophilic surfaces. Interlayer water was also quantified from water vapor isotherm, X-ray diffraction (XRD), and thermal gravimetric analyses (TGA) data, displaying nonreversible swelling/shrinkage behavior in response to drying/rewetting cycles. From this quantification and balance of water distribution, we were able to explain most of the widely dispersed data already published according to the various relative humidity (RH) conditions and measurement techniques. Stoichiometric formulas were proposed for the different CSH samples analyzed (0.6 < Ca/Si < 1.6), considering the interlayer water contribution.

2.
Chromosome Res ; 20(7): 875-87, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23143649

RESUMEN

It is well established that chromosomes occupy distinct positions within the interphase nuclei, conferring a potential functional implication to the genome. In addition, alterations in the nuclear organisation patterns have been associated with disease phenotypes (e.g. cancer or laminopathies). The human sperm is the smallest cell in the body with specific DNA packaging and the mission of delivering the paternal genome to the oocyte during fertilisation. Studies of nuclear organisation in the sperm have postulated nonrandom chromosome position and have proposed a chromocentre model with the centromeres facing toward the interior and the telomeres toward the periphery of the nucleus. Most studies have assessed the nuclear address in the sperm longitudinally predominantly using centromeric or telomeric probes and to a lesser extent with whole chromosome paints. To date, studies investigating the radial organisation of human sperm have been limited. The purpose of this study was to utilise whole chromosome paints for six clinically important chromosomes (18, 19, 21, 22, X, and Y) to investigate nuclear address by assessing their radial and longitudinal nuclear organisation. A total of 10,800 sperm were analysed in nine normozoospermic individuals. The results have shown nonrandom chromosome position for all chromosomes using both methods of analysis. We present novel radial and polar analysis of chromosome territory localization within the human sperm nucleus. Specifically, a hierarchical organisation was observed radially with chromosomes organised from the interior to the periphery (chromosomes 22, 21, Y, X, 19, and 18 respectively) and polar organisation from the sperm head to tail (chromosomes X, 19, Y, 22, 21, and 18, respectively). We provide evidence of defined nuclear organisation in the human sperm and discuss the function of organisation and potential possible clinical ramifications of these results in regards to male infertility and early human development.


Asunto(s)
Cromosomas Humanos/genética , Espermatozoides/citología , Adulto , Núcleo Celular/genética , Polaridad Celular , Centrómero/genética , Pintura Cromosómica , Cromosomas Humanos/metabolismo , Desarrollo Embrionario , Genoma Humano , Humanos , Hibridación Fluorescente in Situ/métodos , Infertilidad Masculina/genética , Masculino , Persona de Mediana Edad , Cabeza del Espermatozoide , Espermatogénesis/genética , Telómero
3.
HIV Med ; 12(7): 442-6, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21395964

RESUMEN

BACKGROUND: We evaluated the efficacy, safety and tolerability of etravirine in paediatric patients vertically infected with HIV-1. METHODS: A multicentre retrospective study of 23 multidrug-resistant paediatric patients (five children and 18 adolescents) enrolled in the study from 1 September 2007 to 28 February 2010 was carried out. We performed a longitudinal analysis of immunological, virological and clinical data. RESULTS: The median age of the patients was 14.2 years [interquartile range (IQR) 12.5-15.8 years]. At baseline, the median HIV-1 RNA was 29 000 (4.5 log(10) ) HIV-1 RNA copies/mL (range 4300-83 000 copies/mL), the median CD4 T-cell count was 445 cells/µL (range 221-655 cells/µL) and the median CD4 percentage was 19.6% (IQR 13.0-31.0). Remarkably, 16 of 23 patients (70%) harboured one or more etravirine-associated resistance mutations. The backbone regimen included at least two fully active drugs in 91% of patients. After etravirine-based therapy, 20 patients (87%) achieved HIV-1 RNA<400 copies/mL and 18 of 23 (78%) achieved HIV-1 RNA<50 copies/mL: three (13%) within the first month, seven (30%) within the first 4 months, and six (26%) between the 5th and 8th months. CD4 T-cell recovery was observed in 19 patients (83%). The median follow-up time was 48.4 weeks (IQR 35.7-63.4 weeks); four patients (17%) were exposed to etravirine for >120 weeks. Three mild/short-term and two moderate skin rashes were observed in the adolescents. Laboratory abnormalities included hypercholesterolaemia (11 of 23 patients), hypertriglyceridaemia (eight of 23 patients), and reduced high-density lipoprotein cholesterol (10 of 23 patients). Adherence was complete in seven patients (30%). No patients showed complete resistance to etravirine after follow-up. However, three of 21 patients (14%) who initially showed intermediate resistance interrupted etravirine treatment because of virological failure. CONCLUSIONS: We observed a sustained antiviral response and improved immunological parameters in multidrug-resistant paediatric patients, most of whom had received etravirine as part of salvage regimens with at least two fully active drugs.


Asunto(s)
Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Piridazinas/uso terapéutico , Adolescente , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Niño , Preescolar , Farmacorresistencia Viral , Femenino , Infecciones por VIH/epidemiología , Humanos , Masculino , Nitrilos , Pirimidinas , Estudios Retrospectivos , España/epidemiología , Resultado del Tratamiento
4.
Rev Neurol ; 72(10): 343-351, 2021 May 16.
Artículo en Español, Inglés | MEDLINE | ID: mdl-33978228

RESUMEN

INTRODUCTION AND AIM: Perinatal transmission of human immunodeficiency virus (PHIV) is considered a chronic disease that has highlighted several cognitive deficits. From birth to early adulthood, cognition is known to play a fundamental role. However, although neurocognitive processes associated with PHIV have been extensively described by psychometric testing, data is scarce on neural activity from functional magnetic resonance imaging (fMRI) which provides in vivo physiological information. SUBJECTS AND METHODS: We studied described impaired cognitive processes using fMRI on a group of PHIV adolescents with good immunovirological indications and healthy matched controls. Psychological status and neurocognitive functions were also assessed. RESULTS: There were no significant differences between HIV+ and HIV- groups, either on neurocognitive testing nor in fMRI activity for phonological fluency tasks. Prolonged duration of cART was positively associated with greater brain activity in left inferior frontal gyrus (LIFG) which could indicate functional compensation. CONCLUSIONS: These results suggest that neural activity through fMRI in PHIV adolescents with good daily functioning and good immunovirological control may be similar to their peers.


TITLE: Actividad cerebral en jóvenes infectados por el virus de la inmunodeficiencia humana por transmisión vertical: estudio piloto de resonancia magnética funcional.Introducción y objetivos. La infección por el virus de la inmunodeficiencia humana de transmisión vertical (VIH-TV) constituye una enfermedad crónica que puede asociar múltiples alteraciones cognitivas que pueden influenciar el desarrollo de estos pacientes desde la infancia a la vida adulta. Sin embargo, aunque las alteraciones neurocognitivas vinculadas al VIH-TV están ampliamente descritas y valoradas mediante pruebas psicométricas, no existen apenas estudios de actividad neuronal medida a través de la resonancia magnética funcional (RMf). Sujetos y métodos. Analizar la utilidad de la RMf a través de la realización de tareas motoras y de fluidez verbal en un grupo de adolescentes y jóvenes con VIH-TV con buen control inmunovirológico y compararlo con un grupo control negativo de características similares. Se evaluaron también alteraciones psicológicas y funciones neurocognitivas. Resultados. No se encontraron diferencias significativas entre el grupo VIH+ y el grupo control para las tareas ejecutadas durante la RMf ni en la evaluación neurocognitiva. Un mayor tiempo de terapia combinada antirretroviral se asoció de forma directa con una mayor actividad en el giro frontal inferior izquierdo, lo cual podría indicar una posible compensación funcional. Conclusiones. Estos resultados sugieren que la actividad neuronal medida a través de la RMf en adolescentes con VIH-TV y buen control inmunovirológico es similar a la de sus pares.


Asunto(s)
Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Disfunción Cognitiva/fisiopatología , Infecciones por VIH/fisiopatología , Transmisión Vertical de Enfermedad Infecciosa , Imagen por Resonancia Magnética , Adolescente , Adulto , Disfunción Cognitiva/etiología , Estudios Transversales , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/terapia , Infecciones por VIH/transmisión , Humanos , Masculino , Proyectos Piloto , Estudios Prospectivos , Adulto Joven
5.
HIV Med ; 11(4): 245-52, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20050937

RESUMEN

OBJECTIVES: Highly active antiretroviral therapy (HAART) has dramatically changed the natural history of HIV infection in children, but there are few studies in the literature about the incidence of clinical manifestations after HAART in this population, compared with adults. The aim of this study was to describe the influence of the widespread use of HAART on the development of opportunistic infections and organ-specific diseases in HIV-infected children. METHODS: An observational study of a cohort of 366 vertically HIV-infected children followed from 1990 to 2006 was carried out. According to the main antiretroviral protocol used, three calendar periods (CPs) were defined and compared: CP1 (1990-1996: no patients on HAART), CP2 (1997-1999: <60% on HAART) and CP3 (2000-2006: >60% on HAART). RESULTS: Children experienced a progressive increase in CD4 T cell count (P<0.05) and a decrease in HIV viral load from 1996 onwards (P<0.05). Similarly, rates of death, AIDS, opportunistic infections (bacteraemia, candidosis, cryptosporidiosis and bacterial pneumonia) and organ-specific diseases (wasting syndrome, thrombocytopenia, cardiomyopathy, lymphoid interstitial pneumonia and HIV-associated encephalopathy) were lower in CP2 and CP3 than in CP1. CONCLUSIONS: This study provides evidence of improved clinical outcomes in HIV-infected children over time and shows that mortality, AIDS, opportunistic infections and organ-specific diseases declined as HAART was progressively instituted in this population.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Terapia Antirretroviral Altamente Activa , Infecciones por VIH/tratamiento farmacológico , VIH-1 , Adulto , Fármacos Anti-VIH/uso terapéutico , Recuento de Linfocito CD4 , Niño , Preescolar , Estudios de Cohortes , Femenino , Infecciones por VIH/mortalidad , Humanos , Lactante , Recién Nacido , Masculino , España/epidemiología , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento , Carga Viral
6.
Cell Mol Neurobiol ; 30(8): 1327-33, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21088884

RESUMEN

GTPases of the Rho family are molecular switches that play an important role in a wide range of membrane-trafficking processes including neurotransmission and hormone release. We have previously demonstrated that RhoA and Cdc42 regulate calcium-dependent exocytosis in chromaffin cells by controlling actin dynamics, whereas Rac1 regulates lipid organisation. These findings raised the question of the upstream mechanism activating these GTPases during exocytosis. The guanine nucleotide exchange factors (GEFs) that catalyse the exchange of GDP for GTP are crucial elements regulating Rho signalling. Using an RNA interference approach, we have recently demonstrated that the GEFs Intersectin-1L and ß-Pix, play essential roles in neuroendocrine exocytosis by controlling the activity of Cdc42 and Rac1, respectively. This review summarizes these results and discusses the functional importance of Rho GEFs in the exocytotic machinery in neuroendocrine cells.


Asunto(s)
Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Calcio/metabolismo , Exocitosis , Factores de Intercambio de Guanina Nucleótido/metabolismo , Células Neuroendocrinas/metabolismo , Animales , Células PC12 , Ratas , Factores de Intercambio de Guanina Nucleótido Rho
7.
Heliyon ; 6(4): e03600, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32368635

RESUMEN

Delayed neurodevelopment is a common outcome in perinatally HIV-infected children. Our aim was to assess the intellectual profile of our cohort, considering both the infection and socio-environmental related variables. A cross-sectional cohort study was undertaken at seven major hospitals in Spain belonging to the CoRISpeS cohort (n = 97). Patients were followed up according to a standard protocol. Intellectual measures, psychosocial profile and HIV infection-related data have been analysed. The average patient age was 15 years. The median CD4 cell percentage was 35% (1,59). Viral load was undetectable in 80% of the patients and 27% were on AIDS category; 38% of whom had encephalopathy. The average composite score of both crystallized intelligence (CI) and intelligence quotient (IQ) for the cohort was lower than that of the general population (p < 0.001). Results revealed a significant difference of 38% between crystallized and fluid intelligence. There was a clear association between IQ and age of diagnosis (p = 0.022); CI and CDC classification (p = 0.035), CD4 count (p = 0.011) and CD4 nadir (p = 0.001). Higher parental education was associated with better performance across all intelligence scales (p < 0.002). A regression model showed that CI was influenced by the academic level of caregivers (p = 0.002), age at start of cART (p = 0.050) and primary language (p = 0.058). Findings revealed significant differences in verbal and non-verbal intellectual scales resulting in a misleading IQ Composite score. Crystallized intelligence demonstrated the highest level of impairment despite adequate treatment and good immunovirological status, while fluid intelligence results were average. Caregiver level of education was the strongest factor across all intelligence measures.

8.
Int J Tuberc Lung Dis ; 24(3): 303-309, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-32228760

RESUMEN

BACKGROUND: Tuberculosis (TB) is the leading opportunistic infection in children with human immunodeficiency virus (HIV), but is uncommon in low prevalence regions. We aim to describe the changing epidemiology and clinical presentation of TB-HIV co-infection in a cohort of HIV-infected children in Spain.METHODS: Children diagnosed with TB between 1995 and 2016 in the paediatric HIV cohort were identified. The incidence and clinical presentation were compared in three periods: 1995-1999 (P1, before initiation of combined antiretroviral therapy, cART), 2000-2009 (P2, increase in immigration), and 2010-2016 (P3, decrease in immigration).RESULTS: We included 29 TB cases among 1183 children aged <18 years (2.4%, 243/100 000 person-years). The proportion was stable in P1 and P2 (1.3%), but decreased in P3 (0.8%). The median age at TB diagnosis was 6.4 years (IQR 4-10.6); most children in P3 were aged >10 years (20% vs. 23.1% vs. 83.3%, P = 0.01). TB was diagnosed at HIV presentation in 11/29 children (37.9%). Foreign-born children accounted for respectively 0%, 8% and 67% of the total number of children in each period (P ≤ 0.0001). One third had extrapulmonary TB; four children died (13.8%).CONCLUSION: In our cohort, the incidence of TB-HIV co-infection decreased with decline in immigration. In regions with adequate cART coverage and low TB transmission, paediatric TB-HIV coinfection is uncommon, but associated with significant morbidity. Strategies for TB surveillance, diagnosis and treatment in this vulnerable population should be reinforced.


Asunto(s)
Coinfección , Infecciones por VIH , Tuberculosis , Adolescente , Niño , Estudios de Cohortes , Coinfección/epidemiología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Estudios Retrospectivos , España/epidemiología , Tuberculosis/diagnóstico , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiología
9.
Rev Neurol (Paris) ; 164(12): 1028-34, 2008 Dec.
Artículo en Francés | MEDLINE | ID: mdl-18808781

RESUMEN

INTRODUCTION: In an observational multicenter study, we analyzed retrospectively 30 patients with malignant form of multiple sclerosis (MS) treated with mitoxantrone the year following the first neurological event. METHODS: The 30 patients were selected according to Weinshenker criteria of malignant MS (either a "catastrophic" relapse or a quickly aggressive form). We compared clinical and MRI findings the year before with the year following mitoxantrone onset treatment: annualized relapse rates (ARR), EDSS score and percentage of patients with gadolinium enhancing lesions on MRI. RESULTS: A total of 87 relapses were observed in the 5.7 months before and 10 during the year following onset of mitoxantrone treatment. The ARR decreased by 95% (6.0+/-2 before and 0.3+/-0.7 after). Twenty-four patients (80%) were relapse-free one year after onset of mitoxantrone treatment. The EDSS score improved in 87% of MS patients and the mean EDSS decreased by 1.9. Ninety-seven percent had at least gadolinium enhancing lesions before the start of mitoxantrone treatment as compared to 17% after. CONCLUSION: In our experience, mitoxantrone had a rapid and strong impact on the malignant forms of MS with a short disease duration. In this MS subgroup, mitoxantrone should be considered as an early treatment option.


Asunto(s)
Inmunosupresores/uso terapéutico , Mitoxantrona/uso terapéutico , Esclerosis Múltiple/tratamiento farmacológico , Adulto , Progresión de la Enfermedad , Femenino , Gadolinio , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/patología , Estudios Retrospectivos , Prevención Secundaria , Resultado del Tratamiento , Adulto Joven
10.
Rev. neurol. (Ed. impr.) ; 72(10): 343-351, May 16, 2021. tab, ilus, graf
Artículo en Inglés, Español | IBECS (España) | ID: ibc-227878

RESUMEN

Introducción y objetivos: La infección por el virus de la inmunodeficiencia humana de transmisión vertical (VIH-TV) constituye una enfermedad crónica que puede asociar múltiples alteraciones cognitivas que pueden influenciar el desarrollo de estos pacientes desde la infancia a la vida adulta. Sin embargo, aunque las alteraciones neurocognitivas vinculadas al VIH-TV están ampliamente descritas y valoradas mediante pruebas psicométricas, no existen apenas estudios de actividad neuronal medida a través de la resonancia magnética funcional (RMf). Sujetos y métodos:Analizar la utilidad de la RMf a través de la realización de tareas motoras y de fluidez verbal en un grupo de adolescentes y jóvenes con VIH-TV con buen control inmunovirológico y compararlo con un grupo control negativo de características similares. Se evaluaron también alteraciones psicológicas y funciones neurocognitivas. Resultados: No se encontraron diferencias significativas entre el grupo VIH+ y el grupo control para las tareas ejecutadas durante la RMf ni en la evaluación neurocognitiva. Un mayor tiempo de terapia combinada antirretroviral se asoció de forma directa con una mayor actividad en el giro frontal inferior izquierdo, lo cual podría indicar una posible compensación funcional. Conclusiones: Estos resultados sugieren que la actividad neuronal medida a través de la RMf en adolescentes con VIH-TV y buen control inmunovirológico es similar a la de sus pares.(AU)


Introduction and aim: Perinatal transmission of human immunodeficiency virus (PHIV) is considered a chronic disease that has highlighted several cognitive deficits. From birth to early adulthood, cognition is known to play a fundamental role. However, although neurocognitive processes associated with PHIV have been extensively described by psychometric testing, data is scarce on neural activity from functional magnetic resonance imaging (fMRI) which provides in vivo physiological information. Subjects and methods: We studied described impaired cognitive processes using fMRI on a group of PHIV adolescents with good immunovirological indications and healthy matched controls. Psychological status and neurocognitive functions were also assessed. Results: There were no significant differences between HIV+ and HIV– groups, either on neurocognitive testing nor in fMRI activity for phonological fluency tasks. Prolonged duration of cART was positively associated with greater brain activity in left inferior frontal gyrus (LIFG) which could indicate functional compensation. Conclusions: These results suggest that neural activity through fMRI in PHIV adolescents with good daily functioning and good immunovirological control may be similar to their peers.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto Joven , Transmisión Vertical de Enfermedad Infecciosa , VIH/fisiología , Trastornos Neurocognitivos , Neuroimagen , Disfunción Cognitiva , Calidad de Vida , Neurología , Enfermedades del Sistema Nervioso , Espectroscopía de Resonancia Magnética , Proyectos Piloto , Estudios Transversales , Estudios Prospectivos
11.
Trends Endocrinol Metab ; 6(2): 50-4, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18406683

RESUMEN

Estrogen therapy offers women important benefits, including the potential prolongation of life by prevention of coronary heart disease (CHD) and osteoporotic fractures, and improvement of life by prevention of menopausal symptoms. Not all women can accept the potential side effects and risks, however, which include uterine bleeding, cystic mastitis, fluid retention, and increased risk of uterine cancer and breast cancer. Thus, the benefits and risks must be patiently weighed for each individual, and the alternatives of no treatment or other treatment should be clear. We review here the pertinent information that now makes these decisions quite sound.

12.
Clin Microbiol Infect ; 21(6): 605.e1-9, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25680310

RESUMEN

Drug resistance mutations compromise the success of antiretroviral treatment in human immunodeficiency virus type 1 (HIV-1)-infected children. We report the virologic and clinical follow-up of the Madrid cohort of perinatally HIV-infected children and adolescents after the selection of triple-class drug-resistant mutations (TC-DRM). We identified patients from the cohort carrying HIV-1 variants with TC-DRM to nucleoside reverse transcriptase inhibitors, nonnucleoside reverse transcriptase inhibitors and protease inhibitors according to IAS-USA-2013. We recovered pol sequences or resistance profiles from 2000 to 2011 and clinical-immunologic-virologic data from the moment of TC-DRM detection until December 2013. Viruses harbouring TC-DRM were observed in 48 (9%) of the 534 children and adolescents from 2000 to 2011, rising to 24.4% among those 197 with resistance data. Among them, 95.8% were diagnosed before 2003, 91.7% were Spaniards, 89.6% carried HIV-1-subtype B and 75% received mono/dual therapy as first regimen. The most common TC-DRM present in ≥50% of them were D67NME, T215FVY, M41L and K103N (retrotranscriptase) and L90M (protease). The susceptibility to darunavir, tipranavir, etravirine and rilpivirine was 67.7%, 43.7%, 33.3% and 33.3%, respectively, and all reported high resistance to didanosine, abacavir and nelfinavir. Despite the presence of HIV-1 resistance mutations to the three main antiretroviral families in our paediatric cohort, some drugs maintained their susceptibility, mainly the new protease inhibitors (tipranavir and darunavir) and nonnucleoside reverse transcriptase inhibitors (etravirine and rilpivirine). These data will help to improve the clinical management of HIV-infected children with triple resistance in Spain.


Asunto(s)
Antirretrovirales/farmacología , Antirretrovirales/uso terapéutico , Farmacorresistencia Viral Múltiple , Infecciones por VIH/patología , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , VIH-1/aislamiento & purificación , Adolescente , Adulto , Niño , Preescolar , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Técnicas de Genotipaje , VIH-1/genética , Humanos , Lactante , Recién Nacido , Masculino , Pruebas de Sensibilidad Microbiana , España , Adulto Joven
13.
J Clin Endocrinol Metab ; 79(4): 1110-4, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7962283

RESUMEN

The catecholamine dopamine (D) is involved in the regulation of LH and PRL secretion, whereas a dysregulated noradrenergic system may contribute significantly to symptoms encountered in affective disorders. This explains the attraction of using alpha-methyl-para-tyrosine (AMPT) in neuroendocrine and psychiatric research, as it inhibits both neurotransmitters. PRL has been used as a marker of the effectiveness of AMPT in blocking D function, but no good marker for the effectiveness of AMPT in blocking norepinephrine (NE) is available. The purpose of this study was to determine whether melatonin (M) might serve as such a marker, as its production and secretion are regulated by NE. Seven subjects were given either AMPT or promethazine, which does not alter M secretion, in a randomized, double blind fashion, and 24-h M secretion was studied. Two-way analysis of variance revealed a significant difference in M secretion (F = 13.2; df = 17,102; P = 0.0013), with the following time points being different: 22, 23, 24, 1, 2, 3, 4, 5, and 6 h. Also, 24-h urinary 6-sulfatoxymelatonin excretion correlated highly with 24-h M secretion, expressed as the area under the curve in the AMPT experiment (r = 0.93; P = 0.002), which indicates that AMPT does not alter the metabolism of M. These results demonstrate for the first time that AMPT significantly attenuates nocturnal M secretion. It is concluded that M is a good marker for characterizing the effectiveness of AMPT in inhibiting sympathetic NE activity.


Asunto(s)
Catecolaminas/antagonistas & inhibidores , Ritmo Circadiano , Melatonina/metabolismo , Metiltirosinas/farmacología , Terminales Presinápticos/metabolismo , Adulto , Biomarcadores , Método Doble Ciego , Femenino , Humanos , Masculino , Norepinefrina/antagonistas & inhibidores , Factores de Tiempo , alfa-Metiltirosina
14.
J Clin Endocrinol Metab ; 80(12): 3458-64, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8530583

RESUMEN

To assess the mechanism by which estrogen replacement therapy (ERT) enhances renal calcium conservation in perimenopausal women, we studied 18 normal women in early postmenopause before and after 6 months of ERT (cyclic treatment with transdermal estradiol at 100 micrograms/day and medroxyprogesterone acetate at 10 mg/day for the first 12 days of each cycle). The changes after ERT were: serum ionized calcium and ultrafiltrable calcium, no change; serum intact PTH, 38.2% increase (P < 0.0001); serum 1,25-dihydroxyvitamin D, 23.8% increase (P < 0.0001); urinary calcium excretion, 33.3% decrease (P < 0.001); and deoxypyridinoline (a marker for bone resorption), 19.5% decrease (P < 0.0001). Also, ERT increased tubular reabsorption of calcium (TRCa; 97.6% +/- 0.2% to 98.7% +/- 0.1%; P < 0.0001), and this increase correlated with that in serum PTH (r = 0.49; P < 0.05). After the infusion of human PTH-(1-34), the TRCa maximum was greater after ERT than at baseline (99.4% +/- 0.1% vs. 99.0% +/- 0.1%; P < 0.0001), resulting in decreased calcium excretion (0.9 +/- 0.20 vs. 1.43 +/- 0.20 mumol/dL glomerular filtrate; P < 0.001). Thus, in early postmenopause, the major mechanism of increased renal calcium conservation after ERT is an increase in TRCa due to an increase in serum PTH because of estrogen-induced inhibition of bone resorption. However, ERT also may directly increase the TRCa maximum in response to PTH.


Asunto(s)
Calcio/metabolismo , Terapia de Reemplazo de Estrógeno , Riñón/metabolismo , Posmenopausia , Adulto , Aminoácidos/sangre , Calcitriol/sangre , Calcio/sangre , Calcio/orina , Femenino , Humanos , Riñón/fisiología , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Hormona Paratiroidea/farmacología
15.
Mayo Clin Proc ; 64(7): 874-7, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2528040

RESUMEN

During the past 20 years, the diagnosis and treatment of ectopic pregnancy have improved considerably. With the current diagnostic modalities, patients at risk for ectopic pregnancy can be followed expectantly, and the diagnosis can be made within a few days of the time of anticipated menses. An enhanced understanding of the varied clinical course of ectopic pregnancy has been gained in the process, and greater individualization of patient care has been possible. Patients with spontaneous tubal abortion are being identified, and they may be better served by observation. The precise role and limitations of pharmacologic agents and the new surgical procedures are still being determined, but the ultimate goal with use of these modalities is an improved potential for fertility.


Asunto(s)
Embarazo Ectópico/diagnóstico , Gonadotropina Coriónica/sangre , Femenino , Humanos , Laparoscopía , Embarazo , Embarazo Ectópico/terapia , Radioinmunoensayo , Ultrasonografía
16.
Mayo Clin Proc ; 70(5): 453-63, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7731255

RESUMEN

OBJECTIVE: To review the clinical features, theories of pathogenesis, and current treatment of endometriosis-associated pain and infertility. DESIGN: We review the manifestation of endometriosis and the possible mechanisms that lead to its symptoms, examine the efficacy of current therapeutic options for pelvic pain and infertility, and provide specific recommendations for treatment based on the current literature. MATERIAL AND METHODS: Endometriosis is the presence of hormonally responsive endometrial tissue occurring outside the uterine cavity. This condition may be asymptomatic but is often found in association with pelvic pain or infertility (or both). The precise pathogenesis has not been clearly established but likely involves retrograde menstruation with subsequent seeding of endometrial glands at extrauterine sites. The definitive diagnosis and staging of endometriosis are performed by laparoscopy. Various strategies have been used to treat endometriosis including expectant, medical, surgical, and combination management. RESULTS: The efficacy of treatment varies for pelvic pain and infertility. Endometriosis-associated pain may respond to both medical and surgical management. The use of medical therapy for endometriosis-associated infertility is not supported by current studies. Surgical management of infertility may be efficacious when pelvic anatomy is distorted because of endometriosis. The use of superovulation strategies and in vitro fertilization has been shown to be effective in overcoming endometriosis-associated infertility. CONCLUSION: Pelvic pain and infertility in the presence of endometriosis necessitate individualization of therapy to achieve treatment goals. Neither medical nor surgical management is efficacious in all circumstances. As a better understanding of the pathogenesis of endometriosis evolves, treatment of this perplexing condition will probably continue to improve.


Asunto(s)
Endometriosis/terapia , Adulto , Antígeno Ca-125/aislamiento & purificación , Endometriosis/diagnóstico , Endometriosis/fisiopatología , Femenino , Fertilización In Vitro , Hormonas/uso terapéutico , Humanos , Histerectomía , Infertilidad Femenina/fisiopatología , Infertilidad Femenina/terapia , Laparoscopía , Dolor Pélvico/fisiopatología , Dolor Pélvico/terapia , Superovulación , Procedimientos Quirúrgicos Operativos/métodos , Adherencias Tisulares/cirugía
17.
Mayo Clin Proc ; 69(2): 131-5, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8309263

RESUMEN

OBJECTIVE: In this study, we reviewed the comparative effectiveness of transdermal and oral estrogen therapy in various groups of women. DESIGN: On the basis of published data and personal clinical experience, we compiled recommendations for use of the various modes of estrogen replacement therapy. MATERIAL AND METHODS: The use of injectable estrogen or implantable estrogen pellets can no longer be recommended because of their expense, inconvenience, and unphysiologic pattern of serum estrogen response. The two main estrogen preparations currently used in the United States--orally administered conjugated estrogens and transdermally administered estradiol--undergo different metabolism, and these processes are reflected in differing levels of circulating hormones and hepatic by-products, including blood clotting factors, binding proteins, renin substrate, and apolipoproteins, and in varied composition of the bile. RESULTS: At least theoretically, transdermal estrogen therapy might be more beneficial than oral estrogen therapy for women who smoke cigarettes or who have migraine headaches, hypertriglyceridemia, hepatobiliary disorders, fibrocystic breast disease, or a history of thromboembolism. In contrast, women with hypercholesterolemia might respond better to oral than to transdermal estrogen therapy. CONCLUSION: Additional properly designed clinical studies are necessary before these recommendations for estrogen replacement therapy can be validated or refuted.


Asunto(s)
Terapia de Reemplazo de Estrógeno/métodos , Estrógenos/administración & dosificación , Administración Cutánea , Administración Oral , Estrógenos/efectos adversos , Femenino , Humanos , Factores de Riesgo
18.
Mayo Clin Proc ; 63(5): 453-60, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-3283471

RESUMEN

Estrogen replacement therapy is effective for the prevention and treatment of postmenopausal osteoporosis and should be offered to all women at high risk for osteoporosis. Such therapy is particularly beneficial for prevention of spinal compression fractures; in addition, it alleviates menopausal symptoms (hot flushes, genitourinary symptoms, and changes in mood). In each patient, these benefits must be weighted against the potential risks of endometrial hyperplasia and carcinoma, breast tenderness, hypertension, vascular headaches, and the inconvenience of menstrual bleeding if the uterus is intact. The risk of endometrial cancer associated with estrogen replacement therapy can be considerably reduced by the addition of a progestin, and other side effects can be diminished or eliminated by use of the new transdermal estrogen preparations. Thus, estrogen replacement therapy should be considered in all women who have experienced natural or surgically induced menopause, and it is advisable in women who have osteoporosis or an increased risk for this disorder and no contra-indications to its use. Estrogen replacement therapy should be instituted as soon after menopause as possible and seems to be well tolerated until at least 75 years of age.


Asunto(s)
Estrógenos/uso terapéutico , Osteoporosis/prevención & control , Anciano , Estrógenos/administración & dosificación , Femenino , Humanos , Menopausia , Persona de Mediana Edad , Factores de Riesgo
19.
Mayo Clin Proc ; 73(8): 735-8, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9703298

RESUMEN

OBJECTIVE: To evaluate the effect of three different dosages of transdermally administered 17beta-estradiol on serum lipoproteins in women who had recently experienced surgical menopause. MATERIAL AND METHODS: We undertook a 2-year, randomized, double-blind, placebo-controlled study in which 126 subjects were recruited and stratified by age, and 93 patients completed the protocol. Serum lipoproteins were assessed before initiation of treatment and after 12 and 24 months of therapy with 0.025, 0.05, or 0.1 mg of estradiol daily. RESULTS: Total serum cholesterol and low-density lipoprotein cholesterol showed dose-dependent decreases that reached statistical significance after 2 years of treatment with transdermally administered estradiol. CONCLUSION: This study confirms that transdermally administered 17beta-estradiol has a modest beneficial effect on serum lipoproteins, with decreased levels of total cholesterol and low-density lipoprotein cholesterol.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Estradiol/administración & dosificación , Estradiol/farmacología , Lípidos/sangre , Administración Cutánea , Adulto , Biomarcadores/sangre , Biomarcadores/orina , Método Doble Ciego , Femenino , Humanos , Histerectomía , Región Lumbosacra , Persona de Mediana Edad , Ovariectomía , Estudios Prospectivos , Radio (Anatomía)/efectos de los fármacos , Columna Vertebral/efectos de los fármacos , Factores de Tiempo , Resultado del Tratamiento
20.
Mayo Clin Proc ; 65(11): 1408-14, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2232895

RESUMEN

Parathyroid hormone-related peptide (PTHrP) is expressed in lactating rat mammary glands after suckling, as a result of increases in prolactin rather than suckling per se. In addition, PTHrP produced in the fetal parathyroid glands and placenta may be responsible for stimulation of placental calcium transport. In the current study, we used a radioimmunoassay for human PTHrP to measure levels of the peptide in (1) human breast milk, cow's milk, and two infant formulas; (2) sequential plasma samples in prepartum and postpartum lactating women; (3) women with pathologic hyperprolactinemia; and (4) human umbilical cord blood. In normal subjects, plasma PTHrP levels ranged from less than 2 to 5 pmol/liter. In contrast, human breast milk contained substantially increased levels of immunoreactive PTHrP. Similar elevations were found in cow's milk and in one infant formula. Column chromatography of breast milk demonstrated that PTHrP immunoreactivity included a region of adenylate cyclase stimulating activity, consistent with the presence of biologically active PTHrP. Plasma prepartum PTHrP values did not differ from corresponding postpartum values in lactating women. Women with hyperprolactinemia had a mean plasma PTHrP value in the high-normal range. Umbilical cord blood had considerably suppressed parathyroid hormone values but PTHrP levels that were indistinguishable from those in normal human plasma. Thus, PTHrP is present in high concentrations in breast milk but apparently does not gain access to the maternal circulation in significant amounts. In addition, women with pathologic hyperprolactinemia seem not to have increased levels of circulating PTHrP.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Sangre Fetal/química , Leche Humana/química , Hormona Paratiroidea/análisis , Embarazo/sangre , Proteínas/análisis , Animales , Cromatografía , Femenino , Humanos , Hiperprolactinemia/sangre , Alimentos Infantiles/análisis , Recién Nacido , Lactancia/sangre , Leche/química , Proteína Relacionada con la Hormona Paratiroidea , Periodo Posparto/sangre , Prolactina/sangre , Radioinmunoensayo , Valores de Referencia
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