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1.
Psychoneuroendocrinology ; 144: 105868, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35853381

RESUMEN

BACKGROUND: Mitochondria are multifunctional energy-producing and signaling organelles that support life and contribute to stress adaptation. There is a growing understanding of the dynamic relationship between stress exposure and mitochondrial biology; however, the influence of stress on key domains of mitochondrial biology during early-life, particularly the earliest phases of intra-uterine/prenatal period remains largely unknown. Thus, the goal of this study was to examine the impact of fetal exposure to stress (modeled as the biological construct allostatic load) upon mitochondrial biology in early childhood. METHODS: In n = 30 children (range: 3.5-6 years, 53% male), we quantified mitochondrial content via citrate synthase (CS) activity and mtDNA copy number (mtDNAcn), and measured mitochondrial bioenergetic capacity via respiratory chain enzyme activities (complexes I (CI), II (CII), and IV (CIV)) in platelet-depleted peripheral blood mononuclear cells (PBMCs). In a cohort of healthy pregnant women, maternal allostatic load was operationalized as a latent variable (sum of z-scores) representing an aggregation of early-, mid- and late-gestation measures of neuroendocrine (cortisol), immune (interleukin-6, C-reactive protein), metabolic (homeostasis model assessment of insulin resistance, free fatty acids), and cardiovascular (aggregate systolic and diastolic blood pressure) systems, as well as an anthropometric indicator (pre-pregnancy body mass index [BMI]). RESULTS: An interquartile increase in maternal allostatic load during pregnancy was associated with higher mitochondrial content (24% and 15% higher CS and mtDNAcn), and a higher mitochondrial bioenergetic capacity (16%, 23%, and 25% higher CI, CII and CIV enzymatic activities) in child leukocytes. The positive association between maternal allostatic load during pregnancy and child mitochondrial content and bioenergetic capacity remained significant after accounting for the effects of key pre- and post-natal maternal and child covariates (p's < 0.05, except CI p = 0.073). CONCLUSION: We report evidence that prenatal biological stress exposure, modeled as allostatic load, was associated with elevated child mitochondrial content and bioenergetic capacity in early childhood. This higher mitochondrial content and bioenergetic capacity (per leukocyte) may reflect increased energetic demands at the immune or organism level, and thus contribute to wear-and-tear and pathophysiology, and/or programmed pro-inflammatory phenotypes. These findings provide potential mechanistic insight into the cellular processes underlying developmental programming, and support the potential role that changes in mitochondrial content and bioenergetic functional capacity may play in altering life-long susceptibility for health and disease.


Asunto(s)
Alostasis , Alostasis/fisiología , ADN Mitocondrial , Metabolismo Energético , Femenino , Humanos , Leucocitos Mononucleares/metabolismo , Masculino , Mitocondrias/metabolismo , Embarazo
2.
Int J Obes (Lond) ; 41(9): 1434-1439, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28487552

RESUMEN

BACKGROUND: The importance of energy homeostasis brain circuitry in the context of obesity is well established, however, the developmental ontogeny of this circuitry in humans is currently unknown. Here, we investigate the prospective association between newborn gray matter (GM) volume in the insula, a key brain region underlying energy homeostasis, and change in percent body fat accrual over the first six months of postnatal life, an outcome that represents among the most reliable infant predictors of childhood obesity risk. METHODS: A total of 52 infants (29 male, 23 female, gestational age at birth=39(1.5) weeks) were assessed using structural MRI shortly after birth (postnatal age at MRI scan=25.9(12.2) days), and serial Dual X-Ray Absorptiometry shortly after birth (postnatal age at DXA scan 1=24.6(11.4) days) and at six months of age (postnatal age at DXA scan 2=26.7(3.3) weeks). RESULTS: Insula GM volume was inversely associated with change in percent body fat from birth to six-months postnatal age and accounted for 19% of its variance (ß=-3.6%/S.D., P=0.001). This association was driven by the central-posterior portion of the insula, a region of particular importance for gustation and interoception. The direction of this effect is in concordance with observations in adults, and the results remained statistically significant after adjusting for relevant covariates and potential confounding variables. CONCLUSIONS: Altogether, these findings suggest an underlying neural basis of childhood obesity that precedes the influence of the postnatal environment. The identification of plausible brain-related biomarkers of childhood obesity risk that predate the influence of the postnatal obesogenic environment may contribute to an improved understanding of propensity for obesity, early identification of at-risk individuals, and intervention targets for primary prevention.


Asunto(s)
Adiposidad/fisiología , Corteza Cerebral/anatomía & histología , Metabolismo Energético/fisiología , Sustancia Gris/fisiología , Obesidad Infantil/etiología , Absorciometría de Fotón , Corteza Cerebral/fisiología , Femenino , Humanos , Recién Nacido , Estudios Longitudinales , Masculino , Estudios Prospectivos , Transducción de Señal/fisiología , Aumento de Peso/fisiología
3.
Neuroscience ; 342: 68-100, 2017 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-26434624

RESUMEN

Thyroid hormones (THs) play an obligatory role in many fundamental processes underlying brain development and maturation. The developing embryo/fetus is dependent on maternal supply of TH. The fetal thyroid gland does not commence TH synthesis until mid gestation, and the adverse consequences of severe maternal TH deficiency on offspring neurodevelopment are well established. Recent evidence suggests that even more moderate forms of maternal thyroid dysfunction, particularly during early gestation, may have a long-lasting influence on child cognitive development and risk of neurodevelopmental disorders. Moreover, these observed alterations appear to be largely irreversible after birth. It is, therefore, important to gain a better understanding of the role of maternal thyroid dysfunction on offspring neurodevelopment in terms of the nature, magnitude, time-specificity, and context-specificity of its effects. With respect to the issue of context specificity, it is possible that maternal stress and stress-related biological processes during pregnancy may modulate maternal thyroid function. The possibility of an interaction between the thyroid and stress systems in the context of fetal brain development has, however, not been addressed to date. We begin this review with a brief overview of TH biology during pregnancy and a summary of the literature on its effect on the developing brain. Next, we consider and discuss whether and how processes related to maternal stress and stress biology may interact with and modify the effects of maternal thyroid function on offspring brain development. We synthesize several research areas and identify important knowledge gaps that may warrant further study. The scientific and public health relevance of this review relates to achieving a better understanding of the timing, mechanisms and contexts of thyroid programing of brain development, with implications for early identification of risk, primary prevention and intervention.


Asunto(s)
Encéfalo/embriología , Encéfalo/metabolismo , Hormonas Tiroideas/metabolismo , Animales , Cognición/fisiología , Femenino , Humanos , Embarazo , Complicaciones del Embarazo/metabolismo , Hormonas Tiroideas/deficiencia
4.
Int J Obes (Lond) ; 41(1): 159-169, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27569686

RESUMEN

BACKGROUND/OBJECTIVES: Elevated prepregnancy body mass index (pBMI) and excess gestational weight gain (GWG) constitute important prenatal exposures that may program adiposity and disease risk in offspring. The objective of this study is to investigate the influence of pBMI and GWG on the maternal metabolomic profile across pregnancy, and to identify associations with birth weight. SUBJECTS/METHODS: This is a longitudinal prospective study of 167 nondiabetic women carrying a singleton pregnancy. Women were recruited between March 2011 and December 2013 from antenatal clinics affiliated to the University of California, Irvine, Medical Center. Seven women were excluded from analyses because of a diagnosis of diabetes during pregnancy. A total of 254 plasma metabolites known to be related to obesity in nonpregnant populations were analyzed in each trimester using targeted metabolomics. The effects of pBMI and GWG on metabolites were tested through linear regression and principle component analysis, adjusting for maternal sociodemographic factors, diet, and insulin resistance. A Bonferroni correction was applied for multiple comparison testing. RESULTS: pBMI was significantly associated with 40 metabolites. Nonesterified fatty acids (NEFA) showed a strong positive association with pBMI, with specificity for mono-unsaturated and omega-6 NEFA. Among phospholipids, sphingomyelins with two double bonds and phosphatidylcholines containing 20:3 fatty acid chain, indicative of omega-6 NEFA, were positively associated with pBMI. Few associations between GWG, quality and quantity of the diet, insulin resistance and the maternal metabolome throughout gestation were detected. NEFA levels in the first and, to a lesser degree, in the second trimester were positively associated with birth weight percentiles. CONCLUSIONS: Preconception obesity appears to have a stronger influence on the maternal metabolic milieu than gestational factors such as weight gain, dietary intake and insulin resistance, highlighting the critical importance of preconception health. NEFA in general, as well as monounsaturated and omega-6 fatty acid species in particular, represent key metabolites for a potential mechanism of intergenerational transfer of obesity risk.


Asunto(s)
Peso al Nacer/fisiología , Índice de Masa Corporal , Metabolómica , Mujeres Embarazadas , Adulto , California , Femenino , Humanos , Recién Nacido , Estudios Longitudinales , Masculino , Embarazo , Estudios Prospectivos , Factores de Riesgo , Aumento de Peso
5.
Pediatr Obes ; 12 Suppl 1: 86-93, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-27900852

RESUMEN

BACKGROUND: Newborns exhibit substantial variation in gestational age-adjusted and sex-adjusted fat mass proportion. The antecedent characteristics of fetal body composition that are associated with newborn fat mass proportion are poorly understood. OBJECTIVE: The aim of this study was to determine whether a composite measure of fetal fat mass is prospectively associated with newborn adiposity. METHODS: In a longitudinal study of 109 low-risk pregnancies, fetal ultrasonography was performed at approximately 12, 20 and 30 weeks gestation. Estimated fetal adiposity (EFA) was derived by integrating cross-sectional arm and thigh per cent fat area and anterior abdominal wall thickness. Newborn per cent body fat was quantified by Dual Energy X-Ray Absorptiometry. The association between EFA and newborn per cent body fat was determined by multiple linear regression. RESULTS: After controlling for confounding factors, EFA at 30 weeks was significantly associated with newborn per cent body fat (standardized ß = 0.41, p < 0.001) and explained 24.0% of its variance, which was substantially higher than that explained by estimated fetal weight (8.1%). The observed effect was driven primarily by arm per cent fat area. CONCLUSIONS: A composite measure of fetal adiposity at 30 weeks gestation may constitute a better predictor of newborn per cent body fat than estimated fetal weight by conventional fetal biometry. Fetal arm fat deposition may represent an early indicator of newborn adiposity. After replication, these findings may provide a basis for an improved understanding of the ontogeny of fetal fat deposition, thereby contributing to a better understanding of its intrauterine determinants and the development of potential interventions.


Asunto(s)
Adiposidad/fisiología , Composición Corporal/fisiología , Ultrasonografía Prenatal/métodos , Absorciometría de Fotón , Adulto , Femenino , Edad Gestacional , Humanos , Recién Nacido , Estudios Longitudinales , Masculino , Embarazo , Estudios Prospectivos
6.
Braz J Biol ; 74(2): 493-500, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-25166337

RESUMEN

Podium angustifrons Kohl 1902 is a species of solitary wasp which nests in pre-existing cavities, with neotropical distribution in Argentina, Bolivia, Brazil, Colombia, Guyana and French Guyana. The aim of this study was to investigate the nesting biology of P. angustifrons, discussing aspects of their life history. To capture its nests, wooden trap-nests were installed in the Parque Municipal das Araucárias, Guarapuava (PR), Brazil, from January 2003 to April 2009. A total of 29 nests were collected, all during the warmer months. These showed no vestibular and intercalary cells, and their closures were made up of chewed plants and mud mixed with organic materials and resin-coated surfaces, sometimes showing a layer of lichens. The cells were provisioned with various wild species of cockroaches (Chorisoneura sp, Riata sp and Helgaia sp) in the nymph stage and/or adults. The sex ratio was 4.6 females per male, significantly higher that the expected 1:1. Most pre-pupae entered diapause in winter with development time ranging from 187 to 283 days for females and 180 to 283 days for males. Deaths occurred in 41.66% of cells provisioned, 33.33% were attributed to faulty development and 8.33% to Chrysididae.


Asunto(s)
Comportamiento de Nidificación/fisiología , Avispas/fisiología , Animales , Brasil , Femenino , Estadios del Ciclo de Vida , Masculino , Estaciones del Año , Árboles , Avispas/crecimiento & desarrollo
7.
Stress ; 14(6): 665-76, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21995526

RESUMEN

Because fetal brain development proceeds at an extremely rapid pace, early life experiences have the potential to alter the trajectory of neurodevelopment, which may increase susceptibility for developmental and neuropsychiatric disorders. There is evidence that prenatal maternal stress and anxiety, especially worries specifically related to being pregnant, influence neurodevelopmental outcomes. In the current prospective longitudinal study, we included 89 women for whom serial data were available for pregnancy-specific anxiety, state anxiety, and depression at 15, 19, 25, 31, and 37 weeks gestation. When the offspring from the target pregnancy were between 6 and 9 years of age, their executive function was assessed. High levels of mean maternal pregnancy-specific anxiety over the course of gestation were associated with lower inhibitory control in girls only and lower visuospatial working memory performance in boys and girls. Higher-state anxiety and depression also were associated with lower visuospatial working memory performance. However, neither state anxiety nor depression explained any additional variance after accounting for pregnancy-specific anxiety. The findings contribute to the literature supporting an association between pregnancy-specific anxiety and cognitive development and extend our knowledge about the persistence of this effect until middle childhood.


Asunto(s)
Ansiedad/complicaciones , Función Ejecutiva , Madres , Complicaciones del Embarazo/psicología , Embarazo/psicología , Efectos Tardíos de la Exposición Prenatal/psicología , Adulto , Trastornos de Ansiedad/etiología , Niño , Femenino , Humanos , Masculino , Estudios Prospectivos , Caracteres Sexuales
8.
J Dev Orig Health Dis ; 2(4): 212-7, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25141165

RESUMEN

There is evidence that fetal exposure to maternal stress is associated with adverse birth outcomes. Less is known about the association between fetal responses to a stressor and indicators of fetal maturity and developmental outcomes. The purpose of the present study was to determine whether fetal heart rate (FHR) patterns in response to a startling stimulus at ∼30 weeks of gestation were associated with gestational age at birth and birth weight. FHR was measured in 156 maternal-fetal dyads following a vibroacoustic stimulus. All pregnancies were singleton intrauterine pregnancies in English-speaking women who were primarily married, middle class, White and at least 18 years of age. Group-based trajectory modeling identified five groups of fetuses displaying distinctive longitudinal trajectories of FHR response to the startling stimulus. The FHR group trajectories were significantly associated with birth weight percentile (P < 0.01) even after controlling for estimated fetal weight at the time of assessment and parity, which are the known factors influencing birth weight (P < 0.01). Post hoc analyses indicated that two groups accounted for the association between FHR patterns and birth weight. The group (n = 23) with the lowest birth weight exhibited an immediate FHR deceleration followed by an immediate acceleration that does not recover. An FHR pattern characterized by immediate and fast acceleration to the peak and a slow discovery to baseline was associated with the highest birth weight. This is the first direct evidence showing that low birth weight and the resulting neurological consequences may have their origins in early fetal development.

9.
Braz J Biol ; 70(3): 623-9, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20730350

RESUMEN

The aim of this study was to compare biological aspects of the Pachodynerus species occurring in the Parque Municipal das Araucárias, Guarapuava, Paraná, Southern Brazil. It was carried from December 2001 to December 2004. Forty one nests belonging to 5 species were collected, of which 17 Pachodynerus guadulpensis, 15 Pachodynerus sp., 1 Pachodynerus argentinus, 1 Pachodynerus ca guadulpensis and 7 Pachodynerus nasidens. The nesting activity of Pachodynerus sp., P. argentinus and P. guadulpensis occurred in similar periods, from December to March, with the exception of P.guadulpensis, that built one nest in October. Pachodynerus ca guadulpensis nested in March and P. nasidens from January to April. The nests of Pachodynerus species present a very similar architecture, comprising a linear series of cylindrical cells that fit perfectly into each other forming a continuous tube. With these results we were able to conclude that, even though Pachodynerus species present common characteristics, such as nest architecture, nesting activities and habitats in which they occur, the used resources, mortality rates, etc., vary among groups of species occurring in different regions.


Asunto(s)
Ecosistema , Comportamiento de Nidificación/fisiología , Avispas/fisiología , Animales , Brasil , Femenino , Masculino , Estaciones del Año , Avispas/clasificación
10.
Braz. j. biol ; 70(3): 623-629, Aug. 2010. ilus, tab
Artículo en Inglés | LILACS | ID: lil-555275

RESUMEN

The aim of this study was to compare biological aspects of the Pachodynerus species occurring in the Parque Municipal das Araucárias, Guarapuava, Paraná, Southern Brazil. It was carried from December 2001 to December 2004. Forty one nests belonging to 5 species were collected, of which 17 Pachodynerus guadulpensis, 15 Pachodynerus sp., 1 Pachodynerus argentinus, 1 Pachodynerus ca guadulpensis and 7 Pachodynerus nasidens. The nesting activity of Pachodynerus sp., P. argentinus and P. guadulpensis occurred in similar periods, from December to March, with the exception of P.guadulpensis, that built one nest in October. Pachodynerus ca guadulpensis nested in March and P. nasidens from January to April. The nests of Pachodynerus species present a very similar architecture, comprising a linear series of cylindrical cells that fit perfectly into each other forming a continuous tube. With these results we were able to conclude that, even though Pachodynerus species present common characteristics, such as nest architecture, nesting activities and habitats in which they occur, the used resources, mortality rates, etc., vary among groups of species occurring in different regions.


O objetivo deste trabalho foi comparar aspectos biológicos das espécies de Pachodynerus que ocorrem no Parque Municipal das Araucárias, Guarapuava, Paraná, Sul do Brasil. Ele foi realizado de dezembro de 2001 a dezembro de 2004. Quarenta e um ninhos de cinco espécies foram coletados sendo 17 de Pachodynerus guadulpensis, 15 de Pachodynerus sp., um de Pachodynerus argentinus, um de Pachodynerus ca guadulpensis e sete de Pachodynerus nasidens. As nidificações de Pachodynerus sp., P. argentinus e P. guadulpensis ocorreram de dezembro a março, com exceção de P. guadulpensis, que construiu um ninho em outubro. Pachodynerus ca guadulpensis nidificou em março e P. nasidens de janeiro a abril. Os ninhos de todas as espécies de Pachodynerus apresentaram arquitetura similar, com uma série linear de células cilíndricas que se encaixam perfeitamente umas nas outras, formando um tubo contínuo. Pelos resultados deste estudo nós concluímos que, mesmo apresentando características em comum, como a arquitetura dos ninhos, atividades de nidificação e habitats onde ocorrem, os recursos usados pelas espécies de Pachodynerus bem como as suas taxas de mortalidades, etc., variam entre grupos de espécies que ocorrem em diferentes regiões.


Asunto(s)
Animales , Femenino , Masculino , Ecosistema , Comportamiento de Nidificación/fisiología , Avispas/fisiología , Brasil , Estaciones del Año , Avispas/clasificación
11.
Stress ; 13(3): 214-20, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20392193

RESUMEN

Psychological stress is known to activate the hypothalamic-pituitary-adrenal axis, resulting in the release of cortisol from the adrenal cortex into the bloodstream. Cortisol is the major human stress hormone and its health correlates continue to be investigated by laboratories around the world. One line of research suggests that specific situational variables play a role in the creation of a stressful situation. The current study examined the effects of systematically varying several situational characteristics on the cortisol stress response in 80 healthy young women exposed to a public speaking task. Three main factors and its interactions were investigated by locating the expert panel either inside or outside of the room, having the subjects speak either about themselves or somebody else, and by asking half of the subjects to perform a distractor task in addition to performing the public speaking. We interpreted these manipulations as variations of social evaluative threat, ego-involvement, and divided attention. We hypothesized that the variations and their interactions would cause differences in endocrine stress responses. The results showed that only the manipulation of social-evaluative threat had a significant main effect on the cortisol stress response in women. There was a further trend (p = 0.07) for a four-way interaction effect. No other main or interaction effects could be observed. We conclude that in women, social-evaluative threat affects the endocrine stress response. This is in contrast to a previous study showing no effects of this variation in men. Thus, future studies should more closely investigate sex or gender effects that might be interacting with the situational aspects of a stressful task.


Asunto(s)
Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisario/fisiología , Conducta Social , Habla/fisiología , Estrés Psicológico/fisiopatología , Estrés Psicológico/psicología , Adolescente , Adulto , Femenino , Humanos , Personalidad , Saliva/metabolismo , Estrés Psicológico/metabolismo , Encuestas y Cuestionarios , Adulto Joven
12.
J Neural Transm (Vienna) ; 114(5): 563-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17245537

RESUMEN

Corticosteroid-binding globulin (SERPINA6) deficiency is an extremely rare hereditary disorder characterized by reduced corticosteroid-binding capacity with normal or low plasma corticosteroid-binding globulin concentration, and normal or low basal cortisol levels associated with hypo-/hypertension and muscle fatigue. Here, we present a patient with severe muscle fatigue, normal blood pressure, and abnormal high saliva cortisol levels following a standardized stress test. This patient was found heterozygous for a de novo 367 asparagine-encoding variant of the corticosteroid-binding globulin gene, previously described as "transcortin Lyon". Both parents were homozygous for the ("wildtype") 367 aspartate-encoding allele. To the best of our knowledge, this case represents the first de novo mutation reported for corticosteroid-binding globulin deficiency, implicating a pathogenic role of variants of SERPINA6 in some cases of muscle fatigue.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Fatiga Muscular/genética , Enfermedades Musculares/genética , Enfermedades Musculares/metabolismo , Serpinas/deficiencia , Serpinas/genética , Adulto , Sustitución de Aminoácidos/genética , Análisis Mutacional de ADN , Marcadores Genéticos/genética , Genotipo , Haplotipos , Humanos , Hidrocortisona/metabolismo , Masculino , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatología , Enfermedades Musculares/fisiopatología , Mutación/genética , Saliva/metabolismo , Transcortina
13.
Stress ; 7(2): 119-26, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15512856

RESUMEN

Phosphatidylserine, derived from cow brains, has been shown previously to dampen the ACTH and cortisol response to physical stress. Further research investigated the influence of soy lecithin phosphatidylserine supplementation on mood and heart rate when faced with an acute stressor. In this study, we investigated the effects of soy lecithin phosphatidic acid and phosphatidylserine complex (PAS) supplementation on pituitary adrenal reactivity (ACTH, cortisol) and on the psychological response (Spielberger State Anxiety Inventory stress subscale) to a mental and emotional stressor. Four groups of 20 subjects were treated for three weeks with daily dosages of either 400 mg PAS, 600 mg PAS, 800 mg PAS, or placebo before exposure to the Trier Social Stress Test (TSST). Treatment with 400 mg PAS resulted in a pronounced blunting of both serum ACTH and cortisol, and salivary cortisol responses to the TSST, but did not affect heart rate. The effect was not seen with larger doses of PAS. With regard to the psychological response, 400 mg PAS seemed to exert a specific positive effect on emotional responses to the TSST. While the placebo group showed the expected increase in distress after the test, the group treated with 400 mg PAS showed decreased distress. These data provide initial evidence for a selective stress dampening effect of PAS on the pituitary-adrenal axis, suggesting the potential of PAS in the treatment of stress related disorders.


Asunto(s)
Glycine max/química , Ácidos Fosfatidicos/farmacología , Fosfatidilcolinas/farmacología , Fosfatidilserinas/farmacología , Sistema Hipófiso-Suprarrenal/metabolismo , Estrés Psicológico/metabolismo , Estrés Psicológico/psicología , Hormona Adrenocorticotrópica/sangre , Adulto , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Combinación de Medicamentos , Femenino , Humanos , Hidrocortisona/sangre , Hidrocortisona/metabolismo , Masculino , Ácidos Fosfatidicos/administración & dosificación , Fosfatidilcolinas/administración & dosificación , Fosfatidilserinas/administración & dosificación , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Saliva/metabolismo
14.
Ann N Y Acad Sci ; 1032: 195-7, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15677409

RESUMEN

Glucocorticoids secreted in response to stress modulate memory in animals and humans. Studies in rodents suggest that glucocorticoids enhance memory consolidation but impair delayed retrieval. Similar negative effects on memory retrieval have been reported in humans. The human studies so far have not addressed the issue of emotional valence, which conceivably could modulate the effects of cortisol on retrieval. The present mini-review discusses two recent studies from our laboratories that investigate the influence of emotional valence on the retrieval-impairing effects of cortisol. Both studies observed that cortisol impaired retrieval and that emotional valence influenced these effects. For autobiographical memory the impairing effects were stronger for neutral than for emotional items, whereas for word retrieval the opposite pattern was observed (stronger effects on emotional words). Possible reasons for these results are the different memory domains tested as well as the different sex of the subjects. Future studies will address these issues, which are of relevance for psychiatric disorders such as posttraumatic stress disorder or major depression.


Asunto(s)
Emociones/fisiología , Hidrocortisona/fisiología , Memoria/fisiología , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Caracteres Sexuales , Estrés Psicológico/metabolismo , Estrés Psicológico/psicología
15.
Vasa ; 30(3): 189-94, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11582949

RESUMEN

BACKGROUND: The etiology of thrombangitis obliterans is still unclear. Although cellular infiltration of the vessel wall is known, no studies on peripheral blood mononuclear cells are reported. Therefore, we assessed leucocyte subpopulations and circulating immune complexes in patients with thrombangitis obliterans and a control group of normal people. PATIENTS AND METHODS: 31 patients (40 +/- 2 years, 24 male, 7 female) with thrombangitis obliterans were included, based on the following criteria: age of manifestation, acral ischemia in legs and arms, previous thrombophlebitis or phlebitis saltans. Manifestation of atherosclerosis or other vasculitic manifestations were excluded. Leucocyte subpopulations, levels of C-reactive protein (CRP) and circulating immune complexes (CIC) were investigated. An age-matched control group (n = 25) was recruited from voluntary blood donors. RESULTS: Leucocyte counts in the thrombagitis group (mean +/- SD: 10,839 +/- 782/nl) were significantly different from the control group (6205 +/- 414/nl, p < 0.0001). The same was true for absolute counts of granulocytes, monocytes and lymphocytes. The results were independent from CRP, which was elevated only in 6 patients. Relative counts of naive helper T-cells were significantly lower in the patient group. HLA-DR expression on B-cells was lower on the patients' lymphocytes. The concentrations of IgA, IgG and IgM in CIC were higher in the thrombangitis patients compared to the control group. C1q-binding capacity and phosphatidylserine antibodies showed no differences. CONCLUSIONS: Patients suffering from thrombangitis obliterans show alterations of leucocyte counts and their subpopulations as well as alterations of the humoral (IgCIC) immune system.


Asunto(s)
Complejo Antígeno-Anticuerpo/sangre , Subgrupos de Linfocitos T/inmunología , Tromboangitis Obliterante/inmunología , Adulto , Autoanticuerpos/sangre , Complemento C1q/metabolismo , Femenino , Humanos , Enfermedades del Complejo Inmune/inmunología , Recuento de Linfocitos , Masculino , Fosfatidilserinas/inmunología
16.
Inorg Chem ; 40(23): 6017-21, 2001 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-11681919

RESUMEN

Alkyl- and phenylbis(dimethylamido)gallium, [RGa(NMe(2))(2)](2) [R = Me (1), Et (2), (n)Bu (3), (n)Hx (4), and Ph (5)], were synthesized by reactions of LiNMe(2) with (RGaCl(2))(2). The crystal structure of compound 1 was a disordered mixture of anti and syn isomers, with the ratio of anti/syn being 64:36, which was consistent with the ratio (57:43) found in the (1)H NMR spectrum. The Ga(2)N(2) cores of the anti and syn structures were nonplanar. (1)H NMR spectra indicated the presence of both anti and syn isomers for all of the other substituents. (1)H NMR and mass spectra indicated that a species with the general formula of R(3)Ga(2)(NMe(2))(3) was formed when these compounds were heated at high temperatures.

17.
Inorg Chem ; 40(20): 5279-84, 2001 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-11559092

RESUMEN

Reduction of Na[Ir(CO)4] by sodium metal in (Me2N)3PO, followed by treatment with liquid ammonia, provided high yields (ca. 90%) of unsolvated Na3[Ir(CO)3], a thermally stable, pyrophoric orange solid. This substance contains iridium in its lowest known formal oxidation state of -3 and has been characterized by IR spectroscopy, elemental analyses, and derivative chemistry, i.e., by its conversion to the triphenylgermyl and triphenylstannyl complexes, trans-[Ir(CO)3(EPh3)2](-), E = Ge, Sn. Single-crystal X-ray structures of the tetraethylammonium salts of these species, as well as [Co(CO)3(SnPh3)2](-), confirm the trigonal bipyramidal nature of the anions, originally predicted on the basis of their IR spectra in the carbonyl stretching frequency region. These structural characterizations provide important additional evidence for the presence of metal tricarbonyl units in Na3[M(CO)3], M = Co, Ir.

19.
Clin Hemorheol Microcirc ; 24(3): 167-74, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11455056

RESUMEN

INTRODUCTION: A Raynaud phenomenon can be associated with cold agglutinins or cryoglobulins. Although cold agglutinins or cryoglobulins may lead to severe acral gangrene the finding of relevant titers is rare. Low titers of cold agglutinins or cryoglobulins are detected more frequently but are assumed to be without any importance. OBJECTIVES: To prove a possible diagnostic or prognostic role of low titers of cold agglutinins or cryoglobulins in patients presenting an isolated Raynaud phenomenon we did a retrospective analysis. SETTINGS AND SUBJECTS: In 306 patients (40+/-16 years, range: 15-83 years) with a mean duration of the history of an isolated Raynaud phenomenon of 48+/-73 months we did a clinical examination, an analysis of antinuclear antibodies, extractable antibodies, cold agglutinins, cryoglobulins, plasma and blood viscosity, erythrocyte aggregation and a nail fold capillaroscopy. RESULTS: Low titers of cold agglutinins were found in 49 patients and of cryoglobulins in 7 patients. The finding of such low titers was not associated with extensive clinical symptoms, duration of clinical symptoms, megacapillaries or haemorrhagies in capillaroscopy, pathologic plasma and blood viscosity and erythrocyte aggregation. The follow-up investigations (mean: 3.1+/-1.2 years, range: 3-7 years) revealed no development of a haematological, vasculitic or connective tissue disease in the subgroup of patients who only had low titers of cold agglutinins. CONCLUSION: The detection of low titers of cold agglutinins in patients with isolated Raynaud phenomenon is of no diagnostic or prognostic relevance.


Asunto(s)
Aglutininas/sangre , Crioglobulinas/análisis , Enfermedad de Raynaud/sangre , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Anticuerpos Antinucleares/sangre , Autoanticuerpos/sangre , Viscosidad Sanguínea , Capilares/patología , Capilares/fisiopatología , Agregación Eritrocitaria , Femenino , Humanos , Flujometría por Láser-Doppler , Masculino , Persona de Mediana Edad , Uñas/irrigación sanguínea , Arteria Radial/fisiopatología , Enfermedad de Raynaud/inmunología , Enfermedad de Raynaud/fisiopatología , Valores de Referencia , Arteria Cubital/fisiopatología
20.
Am J Bot ; 88(7): 1301-8, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11454630

RESUMEN

Recent surveys of seed coat morphology in Lobelioideae (Campanulaceae) have demonstrated the systematic utility of such data in the subfamily and led to a revision of the supraspecific classification of Lobelia. Expanding upon these studies, we examined via scanning electron microscopy 41 seed accessions, emphasizing lobelioid genera in which only one or no species had been examined. Most conformed to previously described testal patterns. However, five species of the endemic Hawaiian genus Cyanea, comprising the molecularly defined Hardyi Clade, had a unique testal pattern (here termed Type F), characterized by laterally compressed, almost linear, areoles with rounded, knob-like protuberances on the radial walls at opposite ends. This offered a convenient synapomorphy for recognition of a clade originally defined on a molecular basis. A second unique testal pattern was found in the related Hawaiian endemics Brighamia and Delissea, thus supporting their close relationship. In this type (here termed Type G), the seed coat is irregularly wrinkled (rugose), creating broad, rounded ridges that run more-or-less perpendicular to the long axis of the seed and thus to the long axis of the testal cells. Seed coat morphology also supported the monophyly of all 124 species of Hawaiian Lobelioideae and their probable derivation from Asian species of Lobelia subg. Tupa. Additional studies supported close relationships between (1) the neotropical genera Centropogon and Siphocampylus; (2) the western American genera Legenere and Downingia; and (3) Jamaican Hippobroma and Lobelia sect. Tylomium, a group endemic to the West Indies.

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