997 resultados para Visual dysfunction
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OBJECTIVE: Patients with schizophrenia show deficits in visuospatial working memory and visual pursuit processes. It is currently unclear, however, whether both impairments are related to a common neuropathological origin. The purpose of the present study was therefore to examine the possible relations between the encoding and the discrimination of dynamic visuospatial stimuli in schizophrenia. METHOD: Sixteen outpatients with schizophrenia and 16 control subjects were asked to encode complex disc displacements presented on a screen. After a delay, participants had to identify the previously presented disc trajectory from a choice of six static linear paths, among which were five incorrect paths. The precision of visual pursuit eye movements during the initial presentation of the dynamic stimulus was assessed. The fixations and scanning time in definite regions of the six paths presented during the discrimination phase were investigated. RESULTS: In comparison with controls, patients showed poorer task performance, reduced pursuit accuracy during incorrect trials and less time scanning the correct stimulus or the incorrect paths approximating its global structure. Patients also spent less time scanning the leftmost portion of the correct path even when making a correct choice. The accuracy of visual pursuit and head movements, however, was not correlated with task performance. CONCLUSIONS: The present study provides direct support for the hypothesis that active integration of visuospatial information within working memory is deficient in schizophrenia. In contrast, a general impairment of oculomotor mechanisms involved in smooth pursuit did not appear to be directly related to lower visuospatial working memory performance in schizophrenia.
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Context: Fibroblast growth factor (FGF) 8 is important for GnRH neuronal development with human mutations resulting in Kallmann syndrome. Murine data suggest a role for Fgf8 in hypothalamo-pituitary development; however, its role in the etiology of wider hypothalamo-pituitary dysfunction in humans is unknown.Objective: The objective of this study was to screen for FGF8 mutations in patients with septo-optic dysplasia (n = 374) or holoprosencephaly (HPE)/midline clefts (n = 47).Methods: FGF8 was analyzed by PCR and direct sequencing. Ethnically matched controls were then screened for mutated alleles (n = 480-686). Localization of Fgf8/FGF8 expression was analyzed by in situ hybridization in developing murine and human embryos. Finally, Fgf8 hypomorphic mice (Fgf8(loxPNeo/-)) were analyzed for the presence of forebrain and hypothalamo-pituitary defects.Results: A homozygous p.R189H mutation was identified in a female patient of consanguineous parentage with semilobar HPE, diabetes insipidus, and TSH and ACTH insufficiency. Second, a heterozygous p.Q216E mutation was identified in a female patient with an absent corpus callosum, hypoplastic optic nerves, and Moebius syndrome. FGF8 was expressed in the ventral diencephalon and anterior commissural plate but not in Rathke's pouch, strongly suggesting early onset hypothalamic and corpus callosal defects in these patients. This was consolidated by significantly reduced vasopressin and oxytocin staining neurons in the hypothalamus of Fgf8 hypomorphic mice compared with controls along with variable hypothalamo-pituitary defects and HPE.Conclusion: We implicate FGF8 in the etiology of recessive HPE and potentially septo-optic dysplasia/Moebius syndrome for the first time to our knowledge. Furthermore, FGF8 is important for the development of the ventral diencephalon, hypothalamus, and pituitary. (J Clin Endocrinol Metab 96: E1709-E1718, 2011)
Traitement des dyslipidémies et atteinte hépatique [Lipid-lowering treatment and liver dysfunction].
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Statins are a cornerstone of cardiovascular prevention. Their utilization is mostly well tolerated and safe: the commonly reported hepatic adverse effect is an asymptomatic, reversible and dose-related increase in liver enzyme levels occurring in case of risks factors. Statins do not worsen liver function in most patients with chronic liver diseases, including nonalcoholic fatty liver disease and hepatitis C, and might be used cautionsly. However, decompensated cirrhosis and acute liver failure are contraindications for statins. Routine hepatic biochemical test monitoring is questioned and might be performed in following situations: chronic liver diseases, alcohol consumption, drug interactions. Other causes should be screened and treatment be temporarily withheld in case of an ALT elevation > 3 times the upper limit of the norm.
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Visual implant elastomer (VIE) has recently been employed to investigate different aspects of earthworm ecology. However, a number of fundamental questions relating to the detection and positioning of the tag, its persistence and potential effects on earthworms remain unknown. Seven earthworm species belonging to three ecological groupings, with different pigmentation and burrowing behaviour, were tagged using different coloured VIE. External inspection after two days, one week and 1, 10 and 27 months were followed by preservation, dissection and internal inspection. Tags could be seen in living specimens to 27 months, and dissection revealed that in most cases they were lodged in the coelomic cavity, held in place by septa. However, over longer time periods (more than two years), the chlorogogenous tissue tended to bind to the tags and made external observation increasingly difficult. Migration of the VIE material towards the posterior of the earthworm and potential loss of the tag were only observed on rare occasions, and a recovery rate in excess of 98% was recorded. By introducing a reasonable amount of VIE into segments, just after the clitellum, this technique can become a valuable tool in earthworm ecology and life history studies, particularly in short-medium term laboratory and field experiments.
Meta-analysis: subclinical thyroid dysfunction and the risk for coronary heart disease and mortality
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BACKGROUND: Data on the association between subclinical thyroid dysfunction and coronary heart disease (CHD) and mortality are conflicting. PURPOSE: To summarize prospective evidence about the relationship between subclinical thyroid dysfunction and CHD and mortality. DATA SOURCES: MEDLINE (1950 to January 2008) without language restrictions and reference lists of retrieved articles were searched. STUDY SELECTION: Two reviewers screened and selected cohort studies that measured thyroid function and then followed persons prospectively to assess CHD or mortality. DATA EXTRACTION: By using a standardized protocol and forms, 2 reviewers independently abstracted and assessed studies. DATA SYNTHESIS: Ten of 12 identified studies involved population-based cohorts that included 14 449 participants. All 10 population-based cohort studies examined risks associated with subclinical hypothyroidism (2134 CHD events and 2822 deaths), whereas only 5 examined risks associated with subclinical hyperthyroidism (1392 CHD events and 1993 deaths). In a random-effects model, the relative risk (RR) for subclinical hypothyroidism for CHD was 1.20 (95% CI, 0.97 to 1.49; P for heterogeneity = 0.14; I(2 )= 33.4%). Risk estimates were lower when higher-quality studies were pooled (RR, 1.02 to 1.08) and were higher among participants younger than 65 years (RR, 1.51 [CI, 1.09 to 2.09] for studies with mean participant age <65 years and 1.05 [CI, 0.90 to 1.22] for studies with mean participant age > or =65 years). The RR was 1.18 (CI, 0.98 to 1.42) for cardiovascular mortality and 1.12 (CI, 0.99 to 1.26) for total mortality. For subclinical hyperthyroidism, the RR was 1.21 (CI, 0.88 to 1.68) for CHD, 1.19 (CI, 0.81 to 1.76) for cardiovascular mortality, and 1.12 (CI, 0.89 to 1.42) for total mortality (P for heterogeneity >0.50; I(2 )= 0% for all studies). LIMITATIONS: Individual studies adjusted for different potential confounders, and 1 study provided only unadjusted data. Publication bias or selective reporting of outcomes could not be excluded. CONCLUSION: Subclinical hypothyroidism and hyperthyroidism may be associated with a modest increased risk for CHD and mortality, with lower risk estimates when pooling higher-quality studies and larger CIs for subclinical hyperthyroidism
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We describe a patient presenting with a first generalized convulsion after alcohol consumption, in whom the early postictal finding of a rapidly regressive cortical visual impairment suggested the presence of a posterior reversible encephalopathy. This was confirmed radiologically, and probably represented the key factor in the seizure etiology.
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Bipolar disorder (BD) is associated with substantial morbidity, as well as premature mortality. Available evidence indicates that 'stress-sensitive' chronic medical disorders, such as cardiovascular disease, obesity and Type 2 diabetes mellitus, are critical mediators and/or moderators of BD. Changes in physiologic systems implicated in allostasis have been proposed to impact brain structures and neurocognition, as well as medical comorbidity in this population. For example, abnormalities in insulin physiology, for example, insulin resistance, hyperinsulinemia and central insulinopenia, are implicated as effectors of allostatic load in BD. Insulin's critical role in CNS physiological (e.g., neurotrophism and synaptic plasticity) and pathophysiological (e.g., neurocognitive deficits, pro-apoptosis and amyloid deposition) processes is amply documented. This article introduces the concept that insulin is a mediator of allostatic load in the BD and possibly a therapeutic target.
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An adverse endogenous environment during early life predisposes the organism to develop metabolic disorders. We evaluated the impact of intake of an iso-caloric fructose rich diet (FRD) by lactating mothers (LM) on several metabolic functions of their male offspring. On postnatal d 1, ad libitum eating, lactating Sprague-Dawley rats received either 10% F (wt/vol; FRD-LM) or tap water (controls, CTR-LM) to drink throughout lactation. Weaned male offspring were fed ad libitum a normal diet, and body weight (BW) and food intake were registered until experimentation (60 d of age). Basal circulating levels of metabolic markers were evaluated. Both iv glucose tolerance and hypothalamic leptin sensitivity tests were performed. The hypothalamus was dissected for isolation of total RNA and Western blot analysis. Retroperitoneal (RP) adipose tissue was dissected and either kept frozen for gene analysis or digested to isolate adipocytes or for histological studies. FRD rats showed increased BW and decreased hypothalamic sensitivity to exogenous leptin, enhanced food intake (between 49-60 d), and decreased hypothalamic expression of several anorexigenic signals. FRD rats developed increased insulin and leptin peripheral levels and decreased adiponectinemia; although FRD rats normally tolerated glucose excess, it was associated with enhanced insulin secretion. FRD RP adipocytes were enlarged and spontaneously released high leptin, although they were less sensitive to insulin-induced leptin release. Accordingly, RP fat leptin gene expression was high in FRD rats. Excessive fructose consumption by lactating mothers resulted in deep neuroendocrine-metabolic disorders of their male offspring, probably enhancing the susceptibility to develop overweight/obesity during adult life.
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Con el nombre de Universo de la Comunicación Audiovisual presentamos un proyecto que tiene, como elemento más significativo, la representación en la red de un mapa conceptual formado por las referencias (autores, obras, conceptos) que el profesorado y alumnado hemos propuesto para definir nuestro campo de estudio. El Universo... incluye, además del mapa conceptual, un espacio para el debate y un conjunto de fichas que interrelacionan el mapa con las asignaturas de la licenciatura. El proyecto busca acercar y potenciar la participación del alumnado en el reconocimiento y lectura crítica de aquellos elementos referenciales que, de forma significativa, permiten acotar e identificarse con el propio ámbito de conocimiento, dando visibilidad al procedimiento y haciéndolo público. Desde el Universo... proponemos una nueva aproximación a la competencia general descrita como capacidad crítica de naturaleza multidisciplinaria que dote al alumnado de capacidad de investigación académica y aplicada. Entendemos esta capacitación crítica como un proceso que va desarrollando el alumnado durante todo el grado. Este proceso supone, en una dimensión individual, alcanzar objetivos como el reconocimiento, localización y configuración de un marco referencial propio, y que permite, en su dimensión colectiva, participar en la definición, concreción y trazado de un marco referencial común.
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Ensayo sobre las placas-nicho visigodas y el mihrab y macsura de la mezquita de Córdoba centrado en sus aspectos formales e iconológicos y sus referentes en la arquitectura de poder y la representación simbólica de la divinidad.
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A transitory projection from primary and secondary auditory areas to the contralateral and ipsilateral areas 17 and 18 exists in newborn kittens. Distinct neuronal populations project to ipsilateral areas 17-18, contralateral areas 17-18 and contralateral auditory cortex; they are at different depth in layers II, III, and IV. By postnatal day 38 the auditory to visual projections have been lost, apparently by elimination of axons rather than by neuronal death. While it was previously reported that the elimination of transitory axons is responsible for focusing the origin of callosal connections to restricted portions of sensory areas it now appears that similar events play a more general role in the organization of cortico-cortical networks. Indeed, the elimination of juvenile projections is largely responsible for determining which areas will be connected in the adult.
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Participants in an immersive virtual environment interact with the scene from an egocentric point of view that is, where there bodies appear to be located rather than from outside as if looking through a window. People interact through normal body movements, such as head-turning,reaching, and bending, and within the tracking limitations move through the environment or effect changes within it in natural ways.
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PURPOSE: To assess the evolution of sexual dysfunctions among young males after an average of 15 months follow-up to determine the predictive factors for this evolution and the characteristics differentiating young males who continue reporting a sexual dysfunction from those who do not. METHODS: We conducted a prospective cohort study in two Swiss military recruitment centers mandatory for all Swiss national males aged 18-25 years. A total of 3,700 sexually active young males filled out a questionnaire at baseline (T0) and follow-up (T1: 15.5 months later). Main outcome measures were self-reported premature ejaculation (PE) and erectile dysfunction (ED). RESULTS: Overall, 43.9% of young males who reported (PE) and 51% of those reporting (ED) at T0 still reported it at T1. Moreover, 9.7% developed a PE problem and 14.4% developed an ED problem between T0 and T1. Poor mental health, depression, and consumption of medication without prescription were predictive factors for PE and ED. Poor physical health, alcohol consumption, and less sexual experience were predictive factors for PE. ED persistence was associated with having multiple sexual partners. CONCLUSIONS: This is the first longitudinal study to examine sexual dysfunctions among young males. Our results show high prevalence rates among young males for maintaining or developing a sexual dysfunction over time. Consequently, when consulting with young males, health professionals should inquire about sexual dysfunctions as part of their routine psychosocial assessment and leave the subject open for discussion. Future research should examine in more detail the relationship between sexual dysfunctions and poor mental health.