Vaccine strategies against schistosomiasis

Schistosomiasis, the second major parasitic disease in the world after malaria affects at least 200 million people, 500 million being exposed to the risk of infection. It is widely agreed that a vaccine strategy wich could lead to the induction of effector mechanisms reducing the level of reinfection and ideally parasite fecundity would deeply affect the incidence of pathological manifestations as well as the parasite transmission potentialities. Extensive studies performed in the rat model have allowed the identification of novel effector mechanisms involving IgE antibodies and various inflammatory cell populations (eosinophils, macrophages and platelets) whereas regulation of immune response by blocking antibodies has been evidencial. Recent epidemiological studies have now entirely confirmed in human populations the the role of IgE antibodies in the acquisition of resistance and the association of IgG4 blocking antibodies with increased susceptibility. On the basis of these concepts, several schistosome glutathion S-transferase (Sm 28 GST) appears as a pronising vaccine candidate. Immunization experiments have shown that two complementary goals can be achieved: (a) a partial but significant reduction of the worm population (up to 60//in rats); (b) a significant reduction of parasite fecundity (up in the mice and 85//in cattle) and egg viability (up to 80//). At least two distinct immunological mechanisms account for these two effects. IgE antibodies appear as a major humoral component of acquired resistance whereas IgA antibodies appear as a major humoral factor affecting parasite fecundity. These studies seem to represent a parasite diseases through the identification of potentially protective antigens and of the components of the immune response which vaccination should aim at inducing.

Nash equilibrium strategies in discrete-time finite-horizon dynamic games with risk-and effort-averse players

The objective of this paper is to re-examine the risk-and effort attitude in the context of strategic dynamic interactions stated as a discrete-time finite-horizon Nash game. The analysis is based on the assumption that players are endogenously risk-and effort-averse. Each player is characterized by distinct risk-and effort-aversion types that are unknown to his opponent. The goal of the game is the optimal risk-and effort-sharing between the players. It generally depends on the individual strategies adopted and, implicitly, on the the players' types or characteristics.

Motion compensation strategies in magnetic resonance imaging.

Image quality in magnetic resonance imaging (MRI) is considerably affected by motion. Therefore, motion is one of the most common sources of artifacts in contemporary cardiovascular MRI. Such artifacts in turn may easily lead to misinterpretations in the images and a subsequent loss in diagnostic quality. Hence, there is considerable research interest in strategies that help to overcome these limitations at minimal cost in time, spatial resolution, temporal resolution, and signal-to-noise ratio. This review summarizes and discusses the three principal sources of motion: the beating heart, the breathing lungs, and bulk patient movement. This is followed by a comprehensive overview of commonly used compensation strategies for these different types of motion. Finally, a summary and an outlook are provided.

Withdrawal, "serosorting" and "strategic positioning": use of risk reduction strategies with casual sex partners in men who have sex with men (MSM) in Switzerland, 2007

Introduction: 1) Withdrawal before ejaculation, "serosorting" (to choose a partner of same serostatus) and "strategic positioning" (only insertive vs. only receptive role in anal sex according to serostatus) are known to be used by MSM as alternatives to condom use. 2) Despite their questionable levels of effectiveness they are collectively labelled as "risk reduction strategies" (RRS). Objectives: The aim of this study is to estimate the prevalence and factors related to RRS in men who report unprotected anal intercourse (UAI) with occasional partners in the last 12 months. Methods: 1) In 2007, a module on RRS was included in a repeated national survey conducted among readers of gay newspapers, members of gay organizations and visitors of gay websites (N=2953). 2) Using an anonymous self-completed questionnaire, participants were asked whether, with the aim of avoiding HIV infection, RRS were used with occasional partners. Analysis: 1) Prevalences were calculated in participants who reported UAI with occasional partners in the last 12 months (n=416). 2) A logistic regression was performed, using "at least one RRS" as dependent variable. Number of partners in the last 12 months, HIV-status and usual socio-demographic characteristics were used as independent factors. Result : 1) 70% (292/416) of the participants reporting UAI used at least one RRS when they had unprotected sex with casual partners in the last 12 months (Table 1). 2) Withrawal before ejaculation was the most frequently reported strategy, followed by serosorting and strategic positioning (Table 1). 3) Participants who reported at least one RRS were more likely to be over 30 years and to belong to a gay organisation. HIV-positive and non-tested participants were less likely to report RRS than HIV-negative participants (Table 2). Conclusions: 1) The majority of MSM who reported UAI in the last 12 months tried to reduce risk of HIV transmission by using specific strategies (withdrawal, serosorting, strategic positioning). It is not known, however, to what extent the use of these strategies was systematic. 2) It is necessary to provide MSM with balanced information on these strategies and their respective level of effectiveness. 3) It is important to monitor the use of RRS in HIV behavioural surveillance surveys in MSM.

FOXC2 controls formation and maturation of lymphatic collecting vessels through cooperation with NFATc1.

The mechanisms of blood vessel maturation into distinct parts of the blood vasculature such as arteries, veins, and capillaries have been the subject of intense investigation over recent years. In contrast, our knowledge of lymphatic vessel maturation is still fragmentary. In this study, we provide a molecular and morphological characterization of the major steps in the maturation of the primary lymphatic capillary plexus into collecting lymphatic vessels during development and show that forkhead transcription factor Foxc2 controls this process. We further identify transcription factor NFATc1 as a novel regulator of lymphatic development and describe a previously unsuspected link between NFATc1 and Foxc2 in the regulation of lymphatic maturation. We also provide a genome-wide map of FOXC2-binding sites in lymphatic endothelial cells, identify a novel consensus FOXC2 sequence, and show that NFATc1 physically interacts with FOXC2-binding enhancers. As damage to collecting vessels is a major cause of lymphatic dysfunction in humans, our results suggest that FOXC2 and NFATc1 are potential targets for therapeutic intervention.

Teacher strategies to elicit knowledge from students in the CLIL classroom: the purpose of questions in controlled patterns of teacher-student interaction

This Master Dissertation comprises two parts: a personal reflection and an empirical study. The personal reflection reviews the process of professionalization undergone by its author throughout the Master. The empirical study tackles teacher strategies to elicit knowledge from students in the CLIL classroom and more specifically the purpose of questions in controlled patterns of teacher-student interaction. The theories of relevant authors such as Vigotsky, Mercer and Tsui are used as a framework to analyze the data presented. The analysis shows the different strategies to elicit knowledge used by the teacher and the appropriateness of her questions in the analyzed interaction

The Rio de Janeiro HIV Vaccine Site: I. Recruitment Strategies and Socio-demographic Data of a HIV Negative Homosexual and Bisexual Male Cohort in Rio de Janeiro, Brazil

The initial effort of the Brazilian Ministry of Health to be an active partner in the world effort in the preparation of future accurate human immune deficiency virus (HIV) efficacy trials was the establishment of a multi-centered cohort of homosexual and bisexual men. An open cohort was established to determine the HIV incidence and the socio-behavioral aspects involved in Rio de Janeiro. A total of 318 potential participants, originated from multiple sources (health units, public information, snowball recruitment), were screened and recruitment became effective through the direct involvement of target communities (with the support of Non Governmental Organizations) and the population. Among this group, seropositivity for sexually transmitted diseases was high with 23, 32 and 46% for HIV, syphilis and hepatitis B, respectively. The socio-demographic data from the first 200 participants of this HIV negative cohort suggests that the cohort volunteers are an appropriate sample of the general male population of the State of Rio de Janeiro

The basilar artery international cooperation study (BASICS).

Basilar artery occlusion is a rare cause of stroke with a high case fatality rate and an often poor clinical outcome among survivors. Our limited knowledge on the outcome in patients with basilar artery occlusion comes from small case series of selected patients.STUDY AIM: The main purpose of the registry is to collect preliminary data that will help direct the design of a future clinical treatment trial. The target number of patients included is 500.DESIGN: BASICS is a prospective, observational, multi-center, international registry of consecutive patients presenting with a symptomatic and radiologically confirmed basilar artery occlusion.STUDY OUTCOMES: From November 2002 until December 2006 data have been collected on 400 patients, from 42 centers in 12 countries. Most patients were treated with IA therapy (55%), followed by antithrombotics (29%) and IV thrombolysis (6%). The overall mortality was 45%.

Double gene deletion reveals the lack of cooperation between PPARalpha and PPARbeta in skeletal muscle.

The peroxisome proliferator-activated receptors (PPARs) are involved in the regulation of most of the pathways linked to lipid metabolism. PPARalpha and PPARbeta isotypes are known to regulate muscle fatty acid oxidation and a reciprocal compensation of their function has been proposed. Herein, we investigated muscle contractile and metabolic phenotypes in PPARalpha-/-, PPARbeta-/-, and double PPARalpha-/- beta-/- mice. Heart and soleus muscle analyses show that the deletion of PPARalpha induces a decrease of the HAD activity (beta-oxidation) while soleus contractile phenotype remains unchanged. A PPARbeta deletion alone has no effect. However, these mild phenotypes are not due to a reciprocal compensation of PPARbeta and PPARalpha functions since double gene deletion PPARalpha-PPARbeta mostly reproduces the null PPARalpha-mediated reduced beta-oxidation, in addition to a shift from fast to slow fibers. In conclusion, PPARbeta is not required for maintaining skeletal muscle metabolic activity and does not compensate the lack of PPARalpha in PPARalpha null mice.

The Rise of The Swiss Tax Haven in the Interwar Period: An International Comparison

The history of tax havens during the decades before World War II is still little known. To date, the studies that have focused on the 1920s and 1930s have presented either a very general perspective on the development of tax havens or a narrow national point of view. Based on unpublished historical archives of five countries (Switzerland, Great Britain, Belgium, France, Germany), this paper offers therefore a new comparative appraisal of international tax competition during this period in order to answer the following question: What was the specificity of the Swiss case - already considered a quintessential tax haven at the time - in comparison to other banking centres? The findings of this research study are twofold. First, the 1920s and 1930s appear as something of a golden age of opportunity for avoiding taxation through the relocation of assets. Most of the financial centres granted consistent tax benefits for imported capital, while the limited degree of international cooperation and the usual guarantee of banking secrecy in European countries prevented the taxation of exported assets. Second, within this general environment, the fiscal strategies of a tax haven like Switzerland differed from those of a great financial power like Great Britain. Whereas the Swiss administration readily placed itself at the service of the banking community, British policy was more balanced between the contradictory interests of the Board of Inland Revenue, the Treasury, and the English business circles.

The Inter-municipal Cooperation in Switzerland and the Trend towards Amalgamation

In Switzerland, the ongoing reforms of fiscal federalism put municipalities under increased fiscal stress. A majority of the municipalities had responded by increasing the cooperation with neighbouring municipalities over the last few years. Simultaneously, many discuss or are directly involved in a possible amalgamation project. Accordingly, the paper aimed at describing how cooperation has presently developed between Swiss municipalities, in order to illustrate the existing trend towards amalgamation. Current surveys helped us estimate the growing importance of inter-municipal arrangements together with the surge of amalgamations. A further goal was to investigate if cantonal financial incentives to municipal amalgamation essentially benefit the cantonal community, following the fiscal equivalence principle, or if they rather benefit amalgamating municipalities. In reality, equivalence does not exist. However, this may possibly be the condition to reduce inequality among amalgamating municipalities.

R&D cooperation between Spanish firms and scientific partners: what is the role of tertiary education?

This paper explores the factors that determine firm’s R&D cooperation with different partners, paying special attention on the role of tertiary education (degree and PhDs level) in facilitating the connection between the firms and the to scientific bodies (technology centres, public research centres and universities). Here, we attempt to answer two questions. First, are innovative firms that carry out internal and external R&D activities more likely to cooperate on R&D projects with other partners? Second, do Spanish innovative firms with a high participation of researchers with degrees or PhDs tend to cooperate more with scientific partners? To answer both questions we apply a three-dimensional approach on a firm level Panel Data with a sample of 4.998 manufacturing and services Spanish firms. First, we run a complementary test between external R&D acquisition and skilled research workers and find that firms which carry out external R&D activities obtain a greater return on R&D cooperation when they have skilled workers in R&D, especially in high-tech manufactures and KIS services. Second, we carry out a 2-step tobit model to estimate, in the first stage, the determinants that explain whether Spanish innovative firms cooperate or not; and in the second stage the factors that affect the choice of partners. And third, we apply an ordered probit model to test the marginal effects of explanatory variables on the different partners. Here we contrast some of the most interesting empirical hypotheses of previous studies, and which emphasize the role of employees with degrees and PhDs in facilitating cooperative R&D between firms and scientific partners.