Mutational analysis of the necdin gene in patients with congenital isolated hypogonadotropic hypogonadism

Context: Necdin activates GNRH gene expression and is fundamental for the development, migration, and axonal extension of murine GNRH neurons. In humans, necdin plays a potential role in the hypogonadotropic hypogonadism phenotype in patients with Prader-Willi syndrome. Aim: To investigate necdin gene (NDN) variants in patients with isolated hypogonadotropic hypogonadism (IHH). Patients and methods: We studied 160 Brazilian patients with IHH, which includes 92 with Kallmann syndrome and 68 with normosmic IHH. Genomic DNA was extracted and the single NDN exon was amplified and sequenced. To measure GNRH transcriptional activity, luciferase reporter plasmids containing GNRH regulatory regions were transiently transfected into GT1-7 cells in the presence and absence of overexpressed wild-type or mutant necdin. Results: A heterozygous variant of necdin, p.V318A, was identified in a 23-year-old male with Kallmann syndrome. The p.V318A was also present in affected aunt and his father and was absent in 100 Brazilian control subjects. Previous FGFR1 gene analysis revealed a missense mutation (p.P366L) in this family. Functional studies revealed a minor difference in the activation of GNRH transcription by mutant protein compared with wild type in that a significant impairment of the necdin protein activity threshold was observed. Conclusion: A rare variant of necdin (p.V318A) was described in a family with Kallmann syndrome associated with a FGFR1 mutation. Familial segregation and in vitro analysis suggested that this non-synonymous variant did not have a direct causative role in the hypogonadism phenotype. NDN mutations are not a frequent cause of congenital IHH.

Prospective analysis between the therapy of immunosuppressive medication and allogeneic microchimerism after liver transplantation

After liver transplantation, migration of donor-derived hematopoietic cells to recipient can be detected in pheripheral blood. This state is termed microchimerism. The aim of this study was to investigate prospectively the presence of allogeneic microchimerism, the occurrence of acute cellular rejection and the level of immunosuppression in transplanted patients. Microchimerism occurrence between 10 days and 12 months after liver transplantation was analyzed in 47 patients aged between 15 and 65 by a two-stage nested PCR/SSP technique to detect donor MHC HLA-DR gene specifically. A pre-transplant blood sample was colleted from each patient to serve as individual negative control. Microchimerism was demonstrated in 32 (68%) of the 47 patients; of these, only 10 patients (31.2%) presented rejection. Early microchimerism was observed in 25 patients (78.12%) and late microchimerism in 7 patients (21.8%). Among the patients with microchimerism, 14 were given CyA and 18 were given FK506. In the group without microchimerism, 12 patients were given CyA and 03 were given FK506. There was a significant association between the presence of microchimerism and the absence of rejection (p=0.02) and also between microchimerism and the type of immunosuppression used. Our data indicate that microchimerism and probably differentiation of donor-derived leukocytes can have relevant immunologic effects both in terms of sensitization of recipient and in terms of immunomodulation toward tolerance induction. (C) 2008 Elsevier B.V. All rights reserved.

Migration in Afro-Brazilian Rural Communities: Crossing Demographic and Genetic Data

Many studies have used genetic markers to understand global migration patterns of our species. However, there are only few studies of human migration on a local scale. We, therefore, researched migration dynamics in three Afro-Brazilian rural communities, using demographic data and ten Ancestry Informative Markers. In addition to the description of migration and marriage structures, we carried out genetic comparisons between the three populations, as well as between locals and migrants from each community. Genetic admixture analyses were conducted according to the gene-identity method, with Sub-Saharan Africans, Amerindians, and Europeans as parental populations. The three analyzed Afro-Brazilian rural communities consisted of 16% to 30% of migrants, most of them women. The age pyramid revealed a gap in the segment of men aged between 20 to 30 yrs. While endogamous marriages predominated, exogamous marriages were mainly patrilocal. Migration dynamics are apparently associated with matrimonial customs and other social practices of such communities. The impact of migration upon the populations` genetic composition was low but showed an increase in European alleles with a concomitant decrease in the Amerindian contribution. Admixture analysis evidenced a higher African contribution to the gene pool of the studied populations, followed by the contribution of Europeans and Amerindians, respectively.

Economic Incentives to Conserve Wildlife on Private Lands: Analysis and Policy

Some believe that provision of private property rights in wildlife on private land can provide a powerful economic incentive for nature conservation because it enables property owners to market such wildlife or its attributes. If such marketing is profitable, private landholders will conserve the wildlife concerned and its required habitat. But land is not always most profitably used for exploitation of wildlife, and many economic values of wildlife (such as non-use economic values) cannot be marketed. The mobility of some wildlife (their fugitive nature) adds to the limitations of the private property approach. While some species may be conserved by this approach, it is suboptimal as a single policy approach to nature conservation. Nevertheless, it is being experimented with in the Northern Territory of Australia where landholders have the possibility of harvesting on their properties a quota of eggs and chicks of red-tailed black cockatoos for commercial sale. This scheme is expected to provide an incentive to private landholders to retain hollow trees essential for the nesting of these birds. Aspects of this approach are analysed using this case, and related ones, from Northern Australia. It is noted that the private property rights approach adopted in southern Africa is unlikely to be equally successful everywhere. The long-term survival of some species depends on their ability to use private lands without severe harassment, either for their migration or to supplement their available resources, for example, the Asian elephant in Sri Lanka. Nature conservation on private land is often a useful, if not essential, supplement to conservation on public lands. Community and public incentives for such conservation are outlined.

Diversity and commonality in national identities: an exploratory analysis of cross-national patterns

Issues of boundary maintenance are implicit in all studies of national identity. By definition, national communities consist of those who are included but surrounded (literally or metaphorically) by those who are excluded. Most extant research on national identity explores criteria for national membership largely in terms of official or public definitions described, for example, in citizenship and immigration laws or in texts of popular culture. We know much less about how ordinary people in various nations reason about these issues. An analysis of cross-national (N = 23) survey data from the 1995 International Social Science Program reveals a core pattern in most of the countries studied. Respondents were asked how important various criteria were in being 'truly' a member of a particular nation. Exploratory factor analysis shows that these items cluster in terms of two underlying dimensions. Ascriptive/objectivist criteria relating to birth, religion and residence can be distinguished from civic/voluntarist criteria relating to subjective feelings of membership and belief in core institutions. In most nations the ascriptive/objectivist dimension of national identity was more prominent than the subjective civic/voluntarist dimension. Taken overall, these findings suggest an unanticipated homogeneity in the ways that citizens around the world think about national identity. To the extent that these dimensions also mirror the well-known distinction between ethnic and civic national identification, they suggest that the former remains robust despite globalization, mass migration and cultural pluralism. Throughout the world official definitions of national identification have tended to shift towards a civic model. Yet citizens remain remarkably traditional in outlook. A task for future research is to investigate the macrosociological forces that produce both commonality and difference in the core patterns we have identified.

Testing insect movement theory: empirical analysis of pest data routinely collected from agricultural crops

Observations of an insect's movement lead to theory on the insect's flight behaviour and the role of movement in the species' population dynamics. This theory leads to predictions of the way the population changes in time under different conditions. If a hypothesis on movement predicts a specific change in the population, then the hypothesis can be tested against observations of population change. Routine pest monitoring of agricultural crops provides a convenient source of data for studying movement into a region and among fields within a region. Examples of the use of statistical and computational methods for testing hypotheses with such data are presented. The types of questions that can be addressed with these methods and the limitations of pest monitoring data when used for this purpose are discussed. (C) 2002 Elsevier Science B.V. All rights reserved.

Contextual determinants of induced abortion: a panel analysis

ABSTRACT OBJECTIVE Analyze the contextual and individual characteristics that explain the differences in the induced abortion rate, temporally and territorially. METHODS We conducted an econometric analysis with panel data of the influence of public investment in health and per capita income on induced abortion as well as a measurement of the effect of social and economic factors related to the labor market and reproduction: female employment, immigration, adolescent fertility and marriage rate. The empirical exercise was conducted with a sample of 22 countries in Europe for the 2001-2009 period. RESULTS The great territorial variability of induced abortion was the result of contextual and individual socioeconomic factors. Higher levels of national income and investments in public health reduce its incidence. The following sociodemographic characteristics were also significant regressors of induced abortion: female employment, civil status, migration, and adolescent fertility. CONCLUSIONS Induced abortion responds to sociodemographic patterns, in which the characteristics of each country are essential. The individual and contextual socioeconomic inequalities impact significantly on its incidence. Further research on the relationship between economic growth, labor market, institutions and social norms is required to better understand its transnational variability and to reduce its incidence.

Proteomic analysis of the influence of the adipocyte secretome on Glioma Gl261 cells

Glioma is the most frequent form of malignant brain tumor in the adults and childhood. There is a global tendency toward a higher incidence of gliomas in highly developed and industrialized countries. Simultaneously obesity is reaching epidemic proportions in such developed countries. It has been highly accepted that obesity may play an important role in the biology of several types of cancer. We have developed an in vitro method for the understanding of the influence of obesity on glioma mouse cells (Gl261). 3T3-L1 mouse pre-adipocytes were induced to the maturity. The conditioned medium was harvested and used into the Gl261 cultures. Using two-dimension electrophoresis it was analyzed the proteome content of Gl261 in the presence of conditioned medium (CGl) and in its absence (NCGl). The differently expressed spots were collected and analyzed by means of mass spectroscopy (MALDI-TOF-MS). Significantly expression pattern changes were observed in eleven proteins and enzymes. RFC1, KIF5C, ANXA2, N-RAP, RACK1 and citrate synthase were overexpressed or only present in the CGl. Contrariwise, STI1, hnRNPs and phosphoglycerate kinase 1 were significantly underexpressed in CGl. Aldose reductase and carbonic anhydrase were expressed only in NCGl. Our results show that obesity remodels the physiological and metabolic behavior of glioma cancer cells. Also, proteins found differently expressed are implicated in several signaling pathways that control matrix remodeling, proliferation, progression, migration and invasion. In general our results support the idea that obesity may increase glioma malignancy, however, some interesting paradox finding were also reported and discussed.

Clinical Outcome and Morphologic Analysis after Endovascular Aneurysm Repair Using the Excluder Endograft

OBJECTIVE: Long-term follow-up after endovascular aneurysm repair (EVAR) is very scarce, and doubt remains regarding the durability of these procedures. We designed a retrospective cohort study to assess long-term clinical outcome and morphologic changes in patients with abdominal aortic aneurysms (AAAs) treated by EVAR using the Excluder endoprosthesis (W. L. Gore and Associates, Flagstaff, Ariz). METHODS: From 2000 to 2007, 179 patients underwent EVAR in a tertiary institution. Clinical data were retrieved from a prospective database. All patients treated with the Excluder endoprosthesis were included. Computed tomography angiography (CTA) scans were retrospectively analyzed preoperatively, at 30 days, and at the last follow-up using dedicated tridimensional reconstruction software. For patients with complications, all remaining CTAs were also analyzed. The primary end point was clinical success. Secondary end points were freedom from reintervention, sac growth, types I and III endoleak, migration, conversion to open repair, and AAA-related death or rupture. Neck dilatation, renal function, and overall survival were also analyzed. RESULTS: Included were 144 patients (88.2% men; mean age, 71.6 years). Aneurysms were ruptured in 4.9%. American Society of Anesthesiologists classification was III/IV in 61.8%. No patients were lost during a median follow-up of 5.0 years (interquartile range, 3.1-6.4; maximum, 11.2 years). Two patients died of medical complications ≤ 30 days after EVAR. The estimated primary clinical success rates at 5 and 10 years were 63.5% and 41.1%, and secondary clinical success rates were 78.3% and 58.3%, respectively. Sac growth was observed in 37 of 142 patients (26.1%). Cox regression showed type I endoleak during follow-up (hazard ratio, 3.74; P = .008), original design model (hazard ratio, 3.85; P = .001), and preoperative neck diameter (1.27 per mm increase, P = .006) were determinants of sac growth. Secondary interventions were required in 32 patients (22.5%). The estimated 10-year rate of AAA-related death or rupture was 2.1%. Overall life expectancy after AAA repair was 6.8 years. CONCLUSIONS: EVAR using the Excluder endoprosthesis provides a safe and lasting treatment for AAA, despite the need for maintained surveillance and secondary interventions. At up to 11 years, the risk of AAA-related death or postimplantation rupture is remarkably low. The incidences of postimplantation sac growth and secondary intervention were greatly reduced after the introduction of the low-permeability design in 2004.

Scientific authorships and collaboration network analysis on Chagas disease: papers indexed in PubMed (1940-2009)

Chagas disease is a chronic, tropical, parasitic disease, endemic throughout Latin America. The large-scale migration of populations has increased the geographic distribution of the disease and cases have been observed in many other countries around the world. To strengthen the critical mass of knowledge generated in different countries, it is essential to promote cooperative and translational research initiatives. We analyzed authorship of scientific documents on Chagas disease indexed in the Medline database from 1940 to 2009. Bibliometrics was used to analyze the evolution of collaboration patterns. A Social Network Analysis was carried out to identify the main research groups in the area by applying clustering methods. We then analyzed 13,989 papers produced by 21,350 authors. Collaboration among authors dramatically increased over the study period, reaching an average of 6.2 authors per paper in the last five-year period. Applying a threshold of collaboration of five or more papers signed in co-authorship, we identified 148 consolidated research groups made up of 1,750 authors. The Chagas disease network identified constitutes a "small world," characterized by a high degree of clustering and a notably high number of Brazilian researchers.

Mapping of Chagas disease research: analysis of publications in the period between 1940 and 2009

INTRODUCTION: Publications are often used as a measure of success in research work. Chagas disease occurs in Central and Southern America. However, during the past years, the disease has been occurring outside Latin America due to migration from endemic zones. This article describes a bibliometric review of the literature on Chagas disease research indexed in PubMed during a 70-year period. METHODS: Medline was used via the PubMed online service of the U.S. National Library of Medicine from 1940 to 2009. The search strategy was: Chagas disease [MeSH] OR Trypanosoma cruzi [MeSH]. RESULTS: A total of 13,989 references were retrieved. The number of publications increased steadily over time from 1,361 (1940-1969) to 5,430 (2000-2009) (coefficient of determination for linear fit, R²=0.910). Eight journals contained 25% of the Chagas disease literature. Of the publications, 64.2% came from endemic countries. Brazil was the predominant country (37%), followed by the United States (17.6%) and Argentina (14%). The ranking in production changed when the number of publications was normalized by estimated cases of Chagas disease (Panama and Uruguay), population (Argentina and Uruguay), and gross domestic product (Bolivia and Brazil). CONCLUSIONS: Several Latin American countries, where the prevalence of T. cruzi infection was not very high, were the main producers of the Chagas disease literature, after adjusting for economic and population indexes. The countries with more estimated cases of Chagas disease produced less research on Chagas disease than some developed countries.

Inverted Haavelmo Effects in a General Equilibrium Analysis of the Impact of Implementing the Scottish Variable Rate of Income Tax.

The Scottish Parliament has the authority to make a balanced-budget expansion or contraction in public expenditure, funded by corresponding local changes in the basic rate of income tax of up to 3p in the pound. This fiscal adjustment is known as the Scottish Variable Rate of income tax, though it has never, as yet, been used. In this paper we attempt to identify the impact on aggregate economic activity in Scotland of implementing these devolved fiscal powers. This is achieved through theoretical analysis and simulation using a Computable General Equilibrium (CGE) model for Scotland. This analysis generalises the conventional Keynesian model so that negative balanced-budget multipliers values are possible, reflecting a regional “inverted Haavelmo effect”. Key parameters determining the aggregate economic impact are the extent to which the Scottish Government create local amenities valuable to the Scottish population and the extent to which this is incorporated into local wage bargaining.

Bringing actors and violent conflict into forced migration literature. A model of the decision to return

Populations displaced as a result of mass violent conflict have become one of the most pressing humanitarian concerns of the last decades. They have also become one salient political issue as a perceived burden (in economic and security terms) and as an important piece in the shift towards a more interventionist paradigm in the international system, based on both humanitarian and security grounds. The saliency of these aspects has detracted attention from the analysis of the interactions between relocation processes and violent conflict. Violent conflict studies have also largely ignored those interactions as a result of the consideration of these processes as mere reaction movements determined by structural conditions. This article takes the view that individual’s agency is retained during such processes, and that it is consequential, calling for the need to introduce a micro perspective. Based on this, a model for the individual’s decision of return is presented. The model has the potential to account for the dynamics of return at both the individual and the aggregate level. And it further helps to grasp fundamental interconnections with violent conflict. Some relevant conclusions are derived for the case of Bosnia-Herzegovina and about the implications of the politicization of return.

Role of ENaC in skin wound healing and phenotypic analysis of GILZ-deficient mice

In my first project, I analyzed the role of the amiloride-sensitive epithelial sodium channel ENaC) in the skin during wound healing. ENaC is present in the skin and a function in keratinocyte differentiation and barrier formation has been demonstrated. Previous findings suggested, that ENaC might be implicated in keratinocyte migration, although its role in wound healing was not analyzed yet. Using skin-specific (K14-Cre) conditional ENaC knockout and overexpressing mice, I determined the wound closure kinetic and performed morphometric measurements. The time course of wound repair was not significantly different in knockouts or transgenics when compared to control mice and the morphology of the closing wound was not altered. In my second project, I studied the glucocorticoid-induced leucine zipper (GILZ, Tsc22d3). GILZ is widely expressed and an important role has been predicted in immunity, adipogenesis and renal sodium handling. Mice were generated that constitutively lack all the functional domains of the Gilz gene. In these mice, the expression of GILZ mRNA transcripts and protein were completely abolished in all tissues tested. Surprisingly, knockout mice survived. To test whether GILZ mimicks glucocorticoid action, we studied its implication in T- and B- cell development and in a model of sepsis. We measured cytokine secretion in different inflammatory models, like in peritoneal and bone marrow-derived macrophages, in splenocytes and a model of sepsis. In all our experiments, cytokine secretion from GILZ- deficient cells was not different from controls. From 6 months onwards, knockout mice contained significantly less body fat and were lighter. Following sodium and water deprivation experiments, water and salt homeostasis was preserved. Sterility of knockout males was associated with a severe testis dysplasia, smaller seminiferous tubules, the number of Sertoli and germ cell was reduced while increased apoptosis, but not cell proliferation, was evidenced. The interstitial Leydig cell population was augmented, and higher plasma FSH and testosterone levels were found. Interestingly, the expression of the target gene Ppar2 was diminished in the testis and in the liver, but not in the skin, kidney or fat. Tsc22d1 mRNA transcript level was found to be upregulated in testis, but not in the kidney or fat tissue. In most tissue, excepted the testis, GILZ-deficient mice reveal functional redundancy amongst members of the Tsc22d family or genes involved in the same regulatory pathways. In summary, contrarily to the published in vitro data, GILZ does not play a crucial role attributed in immunology or inflammation, but we identified a novel function in spermatogenesis. -- Dans mon premier projet, j'ai analysé le rôle du canal épithélial sodique sensible à l'amiloride (ENaC) dans la cicatrisation de la peau. ENaC est présent dans la peau et il a une fonction dans la différenciation des kératinocytes et dans la formation de la barrière. Des études suggèrent qu'ENaC pourrait être impliqué dans la migration des kératinocytes, cependant, son rôle dans la cicatrisation n'a pas encore été étudié. A l'aide de souris qui surexpriment ou qui sont knockout pour ENaC, spécifiquement dans la peau (K14-Cre), j'ai analysé le temps de clôture de la cicatrice et j'ai aussi étudié la morphologie de la plaie guérissant. Chez les souris qui surexpriment ou chez les knockouts, la vitesse de fermeture et la morphologie de la cicatrice étaient identiques aux souris contrôles. Dans mon second projet, j'ai étudié le glucocorticoid-induced leucine zipper (GILZ, Tsc22d3). GILZ est largement exprimé et un rôle important a été prédit dans l'immunité, l'adipogénèse et le transport sodique rénal. Des souris ont été générées dont les domaines fonctionnels du gène Gilz sont éliminés. L'expression de GILZ en ARNm et protéine a été complètement abolie dans tous les tissus testés. Étonnamment, ces souris knockout survivent. Afin de tester si GILZ imite les effets des glucocorticoïdes, nous avons étudié son implication dans le développement des cellules T et B ainsi qu'un modèle de septicémie. Nous avons mesuré la sécrétion de cytokines à partir de différents modèles d'inflammation tels que des macrophages péritonéaux ou de moelle, de splénocytes ou encore d'un modèle de septicémie. Dans toutes nos expériences, la sécrétion de cytokines de cellules GILZ-déficientes était semblable. Dès 6 mois, les knockouts contenaient significativement moins de graisses et étaient plus légères. Suite à une privation sodique et aqueuse, l'homéostasie du sel et de l'eau était préservée. Les mâles knockouts présentaient une stérilité accompagnée d'une dysplasie testiculaire sévère, de tubules séminifères étaient plus petits et contenaient un nombre réduit de cellules de Sertoli et de cellules germinales. L'apoptose était augmentée dans ces cellules mais pas la prolifération cellulaire. Le nombre de cellules de Leydig était aussi plus élevé, ainsi que la FSH et la testostérone. L'expression du gène cible Pparγ2 était diminuée dans le testicule et le foie, mais pas dans la peau, le rein ou le tissu adipeux. L'ARNm de Tsc22d1 était plus exprimé dans le testicule, mais pas dans le rein ou le tissu adipeux. Dans la plupart des tissus, sauf le testicule, les souris knockouts révélaient une redondance fonctionnelle des autres membres de la famille Tsc22d ou de gènes impliqués dans les mêmes voies de régulation. En résumé, contrairement aux données in vitro, GILZ ne joue pas un rôle essentiel en immunologie, mais nous avons identifié une nouvelle fonction dans la spermatogénèse.

Population genetic structure and demography analysis in palinurus elephas populations from atlantic and mediterranean waters

Report for the scientific sojourn at the University of Reading, United Kingdom, from January until May 2008. The main objectives have been firstly to infer population structure and parameters in demographic models using a total of 13 microsatellite loci for genotyping approximately 30 individuals per population in 10 Palinurus elephas populations both from Mediterranean and Atlantic waters. Secondly, developing statistical methods to identify discrepant loci, possibly under selection and implement those methods using the R software environment. It is important to consider that the calculation of the probability distribution of the demographic and mutational parameters for a full genetic data set is numerically difficult for complex demographic history (Stephens 2003). The Approximate Bayesian Computation (ABC), based on summary statistics to infer posterior distributions of variable parameters without explicit likelihood calculations, can surmount this difficulty. This would allow to gather information on different demographic prior values (i.e. effective population sizes, migration rate, microsatellite mutation rate, mutational processes) and assay the sensitivity of inferences to demographic priors by assuming different priors.