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The European collaborative study of HIV-infected pregnant women in Europe now indicates a 13% risk of fetal HIV infection (originally thought to be about 30%, and possibly higher in some countries)- Several reports suggest transplacental passage. However, the detailed mechanisms associated with such vertical transmission have not yet been clarified. We have examined the possibility that HIV enters placental tissue from maternal blood via binding to CD4 and Fc receptors (FcR) at the trophoblast level, allowing intraplacental infection. Here we report the detection of several FcR with distinct localization in the placental villus as well as CD4 surface expression on human trophoblast cells. In addition, we show that trophoblastic cells interact specifically with the gp120/gp160 viral envelope protein. By their tissue localization, these receptors could be responsible or the entry of HIV into the fetal placental cells. Furthermore, purified placental cells can be directly infected by HIV in vitro, and the infection is inhibited by soluble CD4. This suggests a crucial role of the CD4 receptor but an additional way of entry cannot be excluded. Such an in vitro model may be suitable for further studies concerning placental HIV transmission and its prevention. [ABSTRACT FROM AUTHOR]

Civil society organizations (CSOs) are a cornerstone of democracy in Europe. Nonetheless, "civil society" and "political society" should not be equated as membership-based organizations are not necessarily politically engaged. This paper theorizes and empirically examines which membership-based CSOs engage in interest representation through sustained advocacy activity. We propose an incentive-theoretical framework on CSO investments in advocacy activities—a collective, non-exclusive incentive from which also non-members can profit—by organizations fundamentally dependent on member support. Theorizing how CSOs' own structural characteristics, resource dependencies, and government demand for CSO input affect how CSOs reconcile selective and collective incentive provision, we test our hypotheses using new data from four recent surveys conducted in four European democracies. In line with our framework, CSOs organizing individual citizens rather than corporate actors and those pursuing member interests are less likely to engage in advocacy, while CSO professionalization and state funding access enhance CSOs' propensities to do so. Furthermore, the analysis shows that the former structural CSO characteristics are similarly relevant for CSO advocacy across distinct country settings, while the role of resource variables is mediated by institutional context revealing an important source of inequality in democratic interest representation. [ABSTRACT FROM AUTHOR]

Background: Previous gene-environment interaction studies of breast cancer risk have provided sparse evidence of interactions. Using the largest available dataset to date, we performed a comprehensive assessment of potential effect modification of 205 common susceptibility variants by 13 established breast cancer risk factors, including replication of previously reported interactions.Methods: Analyses were performed using 28 176 cases and 32 209 controls genotyped with iCOGS array and 44 109 cases and 48 145 controls genotyped using OncoArray from the Breast Cancer Association Consortium (BCAC). Gene-environment interactions were assessed using unconditional logistic regression and likelihood ratio tests for breast cancer risk overall and by estrogen-receptor (ER) status. Bayesian false discovery probability was used to assess the noteworthiness of the meta-analysed array-specific interactions.Results: Noteworthy evidence of interaction at ≤1% prior probability was observed for three single nucleotide polymorphism (SNP)-risk factor pairs. SNP rs4442975 was associated with a greater reduction of risk of ER-positive breast cancer [odds ratio (OR)int = 0.85 (0.78-0.93), Pint = 2.8 x 10-4] and overall breast cancer [ORint = 0.85 (0.78-0.92), Pint = 7.4 x 10-5) in current users of estrogen-progesterone therapy compared with non-users. This finding was supported by replication using OncoArray data of the previously reported interaction between rs13387042 (r2 = 0.93 with rs4442975) and current estrogen-progesterone therapy for overall disease (Pint = 0.004). The two other interactions suggested stronger associations between SNP rs6596100 and ER-negative breast cancer with increasing parity and younger age at first birth.Conclusions: Overall, our study does not suggest strong effect modification of common breast cancer susceptibility variants by established risk factors. [ABSTRACT FROM AUTHOR]

This study reports a cross-cultural test of Social Learning Theory using direct measures of social learning constructs and focusing on the causal structure implied by the theory. Overall, the results strongly confirm the main thrust of the theory. Prior criminal reinforcement and current crime-favorable definitions are highly related in all three contexts and both strongly predict self-projections of criminal behavior. In addition, effects of prior reinforcement on projected misconduct appear to be both direct and indirect (through crime-favorable definitions). Yet, the findings also indicate that the processes underlying direct effects of reinforcement on criminal probabilities may need to be explicated further. Moreover, some types of definitions may be more influential than other types. Finally, parts of the reinforcement process may be affected by socio-cultural contexts. [ABSTRACT FROM PUBLISHER]

Focuses on the influence of the exposure of incendiary Radio Free Europe broadcasts and psychological warfare in the United States on decision making of the Russians during the Hungarian Revolution of 1956. Contribution of the broadcasts to Moscow's lack of faith in Hungarian Prime Minister Imre Nagy; Fear of Hungary's withdrawal from the Warsaw Pact; Participation of Soviet troops in the effort to fill the security vacuum in Hungary.

Current natural populations of Drosophila melanogaster from Eurasia, Africa and Oceania were investigated with regard to the P–M system of hybrid dysgenesis, for both genetic properties (gonadal dysgenesis sterility analyses) and molecular characteristics (number of full-size elements and particular P element deletion-derivatives, the KP elements). Full-size and KP elements are, respectively, at the origin of two distinct regulation systems, the maternally transmitted P cytotype and the KP-mediated repression whose transmission is biparental. The results show both qualitative and quantitative differences in the geographical distribution of P elements. Comparison with distributions observed in 1980–1983 reveals a great stability of natural populations with regard to this system. In particular, the eastward gradient of P susceptibility previously described in Europe is still observed. This stability could result from the existence of a ’buffer zone’ made up of the French and bordering Q populations (with no P activity and completely regulating the transposition of active P elements). Indeed, in such populations repression mechanisms are redundant, as revealed by the study of repression inheritance. These populations are thus potentially able to limit the progression of P elements that occurs by step by step migrations. This distribution also allows us to enrich the P element invasion model, which can be divided into three steps: (1) a decrease in the number of full-size elements which coincides with an increase in the number of KP elements due to a regulatory role or a high transposition capacity; (2) an equilibrium, when the number of KP elements reaches a maximum and in which populations still have some full-size elements; (3) KP elements reduce in number in the absence of full-size elements allowing transposition, the populations losing their repression potential. [ABSTRACT FROM AUTHOR]