Metabolic syndrome according to different definitions in a rapidly developing country of the African region

AIMS: We examined, in a country of the African region, i) the prevalence of the metabolic syndrome (MetS) according to three definitions (ATP, WHO and IDF); ii) the distribution of the MetS criteria; iii) the level of agreement between these three definitions and iv) we also examined these issues upon exclusion of people with diabetes. METHODS: We conducted an examination survey on a sample representative of the general population aged 25-64 years in the Seychelles (Indian Ocean, African region), attended by 1255 participants (participation rate of 80.3%). RESULTS: The prevalence of MetS increased markedly with age. According to the ATP, WHO and IDF definitions, the prevalence of MetS was, respectively, 24.0%, 25.0%, 25.1% in men and 32.2%, 24.6%, 35.4% in women. Approximately 80% of participants with diabetes also had MetS and the prevalence of MetS was approximately 7% lower upon exclusion of diabetic individuals. High blood pressure and adiposity were the criteria found most frequently among MetS holders irrespective of the MetS definitions. Among people with MetS based on any of the three definitions, 78% met both ATP and IDF criteria, 67% both WHO and IDF criteria, 54% both WHO and ATP criteria and only 37% met all three definitions. CONCLUSION: We identified a high prevalence of MetS in this population in epidemiological transition. The prevalence of MetS decreased by approximately 32% upon exclusion of persons with diabetes. Because of limited agreement between the MetS definitions, the fairly similar proportions of MetS based on any of the three MetS definitions classified, to a substantial extent, different subjects as having MetS.

Metabolic syndrome according to different definitions in a rapidly developing country of the African region

Rapport de synth��seLe syndrome m��tabolique repr��sente un ensemble de facteurs de risque m��taboliques souvent pr��sents simultan��ment et il est associ�� �� un risque accru de d��velopper des maladies cardiovasculaires. La prevalence du syndrome m��tabolique est �� la hausse au niveau mondial comme cela a souvent ��t�� document��, en particulier dans les pays d��velopp��s. Pourtant, les donn��es concernant le syndrome m��tabolique dans les pays de la r��gion sub-saharienne restent rares.Au cours des derni��res ann��es, plusieurs d��finitions du syndrome m��tabolique ont ��t�� formul��es, dont celle du 'National Cholesterol Education Program Adult Treatment Panel III', celle de 1 Organisation Mondiale de la Sant�� et celle du 'International Diabetes Federation'. Parmi les controverses au sujet du syndrome m��tabolique persiste la question de l'utilit�� de rechercher la pr��sence du syndrome m��tabolique chez les patients diab��tiques, ��tant donn�� que la pr��sence d'un diab��te en soit suffit pour identifier un individu �� haut risque de faire un ��v��nement cardiovasculaire.L'objectif de ce travail de th��se a ��t�� de d��terminer la pr��valence du syndrome m��tabolique selon les trois d��finitions majeures mentionn��es ci-dessus, gr��ce �� une ��tude de population transversale, r��alis��e aux Seychelles en 2004 dans un ��chantillon repr��sentatif de la population ��g��e de 24-65 ans (n=1255, taux de participation de 80.3%). L'int��r��t d'examiner cette question dans ce pays ��tait d'obtenir des informations dans un pays en transition ��pid��miologique.Les r��sultats de ce travail montrent que la pr��valence du syndrome m��tabolique aux Seychelles est ��lev��e, quelque soit la d��finition utilis��e. Selon la d��finition utilis��e, cette pr��valence ��tait d'environ 25% chez les hommes et variant entre 25 et 35% chez les femmes.Cependant, malgr�� des pr��valences semblables selon ces trois d��finitions, la concordance entre ces d��finitions n'��tait pas bonne, impliquant que ces diff��rentes d��finitions classifient, �� un certain degr��, des individus diff��rents comme ��tant porteurs du syndrome m��tabolique.En outre, la plupart (environ 80%) des individus diab��tiques avaient un syndrome m��tabolique. Apr��s exclusion des individus diab��tiques, la pr��valence du syndrome m��tabolique dans la population est r��duite d'environ un tiers, �� environ 20-25%.Ces r��sultats montrent que, d'une part, le fardeau de maladie d�� au syndrome m��tabolique aux Seychelles, un pays en voie de d��veloppement, est consid��rable. Cette observation peut potentiellement s'appliquer �� d'autres pays �� un stade de d��veloppement semblable. Cela renforce le besoin de mettre en oeuvre des strat��gies de sant�� publique afin de cibler les causes de ces d��sordres m��taboliques, tels que le surpoids et la s��dentarit��. D'un point de vue du diagnostic, les trois d��finitions du syndrome m��tabolique semblent classifier un nombre semblable de personnes atteints du syndrome m��tabolique dans cette population. Par contre, la relativement mauvaise concordance entre ces d��finitions - certaines personnes identifi��s comme porteurs du syndrome m��tabolique selon une d��finition ne le sont pas selon une autre - confirme la n��cessit�� de clarifier la signification de ces diff��rentes d��finitions et/ou ��ventuellement de d��velopper une d��finition unifi��e et fiable du syndrome m��tabolique.

Building hippocampal circuits to learn and remember: insights into the development of human memory

The hippocampal formation is essential for the processing of episodic memories for autobiographical events that happen in unique spatiotemporal contexts. Interestingly, before 2 years of age, children are unable to form or store episodic memories for recall later in life, a phenomenon known as infantile amnesia. From 2 to 7 years of age, there are fewer memories than predicted based on a forgetting function alone, a phenomenon known as childhood amnesia. Here, we discuss the postnatal maturation of the primate hippocampal formation with the goal of characterizing the development of the neurobiological substrates thought to subserve the emergence of episodic memory. Distinct regions, layers and cells of the hippocampal formation exhibit different profiles of structural and molecular development during early postnatal life. The protracted period of neuronal addition and maturation in the dentate gyrus is accompanied by the late maturation of specific layers in different hippocampal regions that are located downstream from the dentate gyrus, particularly CA3. In contrast, distinct layers in several hippocampal regions, particularly CA1, which receive direct projections from the entorhinal cortex, exhibit an early maturation. In addition, hippocampal regions that are more highly interconnected with subcortical structures, including the subiculum, presubiculum, parasubiculum and CA2, mature even earlier. These findings, together with our studies of the development of human spatial memory, support the hypothesis that the differential maturation of distinct hippocampal circuits might underlie the differential emergence of specific "hippocampus-dependent" memory processes, culminating in the emergence of episodic memory concomitant with the maturation of all hippocampal circuits.

How do the different components of episodic memory develop? Role of executive functions and short-term feature-binding abilities.

This study investigated the development of all 3 components of episodic memory (EM), as defined by Tulving, namely, core factual content, spatial context, and temporal context. To this end, a novel, ecologically valid test was administered to 109 participants aged 4-16 years. Results showed that each EM component develops at a different rate. Ability to memorize factual content emerges early, whereas context retrieval abilities continue to improve until adolescence, due to persistent encoding difficulties (isolated by comparing results on free recall and recognition tasks). Exploration of links with other cognitive functions revealed that short-term feature-binding abilities contribute to all EM components, and executive functions to temporal and spatial context, although ability to memorize temporal context is predicted mainly by age.

Iowa Historic Property Study of the Zeman Barn, 2009

The Zeman Barn (86-00028) is an early twentieth-century example of a gothic roofed barn and is part of the Zeman Farmstead located along U.S. Highway 30 in Otter Creek Township (Township 38N, Range 14W), Tama County, Iowa (Figures 1 and 2). The farmstead was initially evaluated in a reconnaissance architectural survey conducted in 1998 by The Louis Berger Group, Inc (Berger). An intensive architectural survey of the property by Berger���s Principal Architectural Historian, Martha H. Bowers, evaluated the farmstead as not being eligible for listing in the National Register of Historic Places (National Register) but noted that the barn appears to be eligible for listing in the National Register under Criterion C (Bowers 1998). At the request of the Iowa Department of Transportation, Berger completed the recordation project to provide a documentary record of the Zeman Barn in accordance with the guidelines set forth by the Iowa State Historic Preservation Office regarding historic property studies for barns. Background research for this project was conducted in September 2008 and April 2009. The property was inspected and photographed in May 2008. Information on the property was gathered through background research, interviews with Zeman family members, field investigation, and photo documentation. Historical maps of the project area were used to collect data necessary for developing regional and local historic contexts. The research for this report was conducted at the Tama County Courthouse and the Tama County Historical Museum Genealogical Library, both in Toledo. Much of the background research for the project was conducted by Camilla Deiber and Michael Dulle. Ms. Deiber also prepared the photographic documentation, plan drawings, and the graphics used in this report. Mr. Roger L. Ciuffo conducted interviews with Zeman family members and wrote this report.

Dissociation between components of spatial memory in rats after recovery from the effects of retrohippocampal lesions

A series of 4 experiments examined the performance of rats with retrohippocampal lesions on a spatial water-maze task. The animals were trained to find and escape onto a hidden platform after swimming in a large pool of opaque water. The platform was invisible and could not be located using olfactory cues. Successful escape performance required the rats to develop strategies of approaching the correct location with reference solely to distal extramaze cues. The lesions encompassed the entire rostro-caudal extent of the lateral and medial entorhinal cortex, and included parts of the pre- and para-subiculum, angular bundle and subiculum. Groups ECR 1 and 2 sustained only partial damage of the subiculum, while Group ECR+S sustained extensive damage. These groups were compared with sham-lesion and unoperated control groups. In Expt 1A, a profound deficit in spatial localisation was found in groups ECR 1 and ECR+S, the rats receiving all training postoperatively. In Expt 1B, these two groups showed hyperactivity in an open-field. In Expt 2, extensive preoperative training caused a transitory saving in performance of the spatial task by group ECR 2, but comparisons with the groups of Expt 1A revealed no sustained improvement, except on one measure of performance in a post-training transfer test. All rats were then given (Expt 3) training on a cueing procedure using a visible platform. The spatial deficit disappeared but, on returning to the normal hidden platform procedure, it reappeared. Nevertheless, a final transfer test, during which the platform was removed from the apparatus, revealed a dissociation between two independent measures of performance: the rats with ECR lesions failed to search for the hidden platform but repeatedly crossed its correct location accurately during traverses of the entire pool. This partial recovery of performance was not (Expt 4) associated with any ability to discriminate between two locations in the pool. The apparently selective recovery of aspects of spatial memory is discussed in relation to O'Keefe and Nadel's (1978) spatial mapping theory of hippocampal function. We propose a modification of the theory in terms of a dissociation between procedural and declarative subcomponents of spatial memory. The declarative component is a flexible access system in which information is stored in a form independent of action. It is permanently lost after the lesion. The procedural component is "unmasked" by the retrohippocampal lesion giving rise to the partial recovery of spatial localisation performance.

Cross-Sectional and Longitudinal Associations between Body Mass Index and Cardiometabolic Risk Factors in Adolescents in a Country of the African Region.

We assessed the association between several cardiometabolic risk factors (CRFs) (blood pressure, LDL-cholesterol, HDL-cholesterol, triglycerides, uric acid, and glucose) in 390 young adults aged 19-20 years in Seychelles (Indian Ocean, Africa) and body mass index (BMI) measured either at the same time (cross-sectional analysis) or at the age of 12-15 years (longitudinal analysis). BMI tracked markedly between age of 12-15 and age of 19-20. BMI was strongly associated with all considered CRFs in both cross-sectional and longitudinal analyses, with some exceptions. Comparing overweight participants with those having a BMI below the age-specific median, the odds ratios for high blood pressure were 5.4/4.7 (male/female) cross-sectionally and 2.5/3.9 longitudinally (P < 0.05). Significant associations were also found for most other CRFs, with some exceptions. In linear regression analysis including both BMI at age of 12-15 and BMI at age of 19-20, only BMI at age of 19-20 remained significantly associated with most CRFs. We conclude that CRFs are predicted strongly by either current or past BMI levels in adolescents and young adults in this population. The observation that only current BMI remained associated with CRFs when including past and current levels together suggests that weight control at a later age may be effective in reducing CRFs in overweight children irrespective of past weight status.

Development of the ability to inhibit a prepotent response: influence of working memory and processing speed.

This study aimed to examine developmental trends in response inhibition during childhood and to control for possible developmental influence of other basic cognitive processes (such as working memory and processing speed). In addition, we explored the relationships between response inhibition, working memory, and processing speed, as they are thought to be integral to cognitive control. Therefore, we assessed these three cognitive abilities in 159 children aged from 5 to 12. Results showed an improvement in response inhibition ability from 5 to 10 years of age. This improvement remained significant after controlling for the influence of working memory and processing speed. Furthermore, the developmental relationships showed an early differentiation between response inhibition, working memory, and processing speed. Thus, these processes were independent and need to be treated as such in further studies.

Commentary. The ontogeny of human memory : where are we going ?

In their review, Jabe`s and Nelson provide an update of Nelson's 1995 cognitive neuroscience model of human memory development. Here, we highlight the major changes in perspective after 20 years of advances in our understanding of the neural basis of memory, and advocate the need for more systematic investigations of memory processes across the lifespan, which combine different models and levels of analysis: from genes, to brain to behavior.

Reversible Reprogramming of Circulating Memory T Follicular Helper Cell Function during Chronic HIV Infection.

Despite the overwhelming benefits of antiretroviral therapy (ART) in curtailing viral load in HIV-infected individuals, ART does not fully restore cellular and humoral immunity. HIV-infected individuals under ART show reduced responses to vaccination and infections and are unable to mount an effective antiviral immune response upon ART cessation. Many factors contribute to these defects, including persistent inflammation, especially in lymphoid tissues, where T follicular helper (Tfh) cells instruct and help B cells launch an effective humoral immune response. In this study we investigated the phenotype and function of circulating memory Tfh cells as a surrogate of Tfh cells in lymph nodes and found significant impairment of this cell population in chronically HIV-infected individuals, leading to reduced B cell responses. We further show that these aberrant memory Tfh cells exhibit an IL-2-responsive gene signature and are more polarized toward a Th1 phenotype. Treatment of functional memory Tfh cells with IL-2 was able to recapitulate the detrimental reprogramming. Importantly, this defect was reversible, as interfering with the IL-2 signaling pathway helped reverse the abnormal differentiation and improved Ab responses. Thus, reversible reprogramming of memory Tfh cells in HIV-infected individuals could be used to enhance Ab responses. Altered microenvironmental conditions in lymphoid tissues leading to altered Tfh cell differentiation could provide one explanation for the poor responsiveness of HIV-infected individuals to new Ags. This explanation has important implications for the development of therapeutic interventions to enhance HIV- and vaccine-mediated Ab responses in patients under ART.

El papel de la memoria de trabajo en el c��lculo mental un cuarto de siglo despu��s de Hitch = The role of working memory in mental arithmetic a quarter of century after Hitch

Desde que Hitch (1978) public�� el primer estudio sobre el rol de la memoria de trabajo en el c��lculo han idoaumentando las investigaciones en este campo. Muchos trabajos han estudiado un ��nico subsistema, pero nuestroobjetivo es identificar qu�� subsistema de la memoria de trabajo (bucle fonol��gico, agenda viso-espacial o ejecutivocentral) est�� m��s implicado en el c��lculo mental. Para ello hemos realizado un estudio correlacional en el quehemos administrado dos pruebas aritm��ticas y nueve pruebas de la ���Bateria de Test de Mem��ria de Treball��� dePickering, Baqu��s y Gathercole (1999) a una muestra de 94 ni��os espa��oles de 7-8 a��os. Nuestros resultadosindican que el bucle fonol��gico y sobretodo el ejecutivo central inciden de forma estad��sticamente significativa enel rendimiento aritm��tico