Two new 3' PML breakpoints in t(15;17)(q22;q21)-positive acute promyelocytic leukemia.

In the present article, two new types of PML/RARA junctions are described. Both were identified in diagnostic samples from two t(15;17)(q22;q21)-positive acute promyelocytic leukemia (APL) patients who failed to achieve complete remission. By using different sets of primers, reverse transcriptase polymerase chain reaction (RT-PCR) of PML/RARA junctions showed atypical larger bands compared with those generated from the three classical PML breakpoints already described. Sequence analysis of the fusion region of the amplified cDNAs allowed us to determine the specificity of these fragments in both patients. This analysis showed two new hybrid transcripts that were 53 and 306 base pairs (bp) longer than that expressed by the NB4 cell line (PML breakpoint within intron 6), and are the result of the direct joining of RARA exon 3 with PML exon 7a (patient 2) or the 5' portion of PML exon 7b (patient 1), respectively. In patient 1, RT-PCR analysis of the reciprocal RARA/PML junction showed a smaller transcript than that expected in bcr1 cases, while in patient 2 no amplified fragment was obtained. Cytogenetic analysis and/or fluorescence in situ hybridization (FISH) showed that both patients had the t(15;17) translocation. The clinical and hematological profiles expressed by the two patients carrying these unexpected types of PML/RARA rearrangement did not differ significantly from that commonly seen in other APLs with the exception of the poor outcome. Genes Chromosomes Cancer 27:35-43, 2000.

A two-step approach for the analysis of hybrids in comparative social policy analysis: a nuanced typology of childcare policies

Typologies have represented an important tool for the development of comparative social policy research and continue to be widely used in spite of growing criticism of their ability to capture the complexity of welfare states and their internal heterogeneity. In particular, debates have focused on the presence of hybrid cases and the existence of distinct cross-national pattern of variation across areas of social policy. There is growing awareness around these issues, but empirical research often still relies on methodologies aimed at classifying countries in a limited number of unambiguous types. This article proposes a two-step approach based on fuzzy-set-ideal-type analysis for the systematic analysis of hybrids at the level of both policies (step 1) and policy configurations or combinations of policies (step 2). This approach is demonstrated by using the case of childcare policies in European economies. In the first step, parental leave policies are analysed using three methods – direct, indirect, and combinatory – to identify and describe specific hybrid forms at the level of policy analysis. In the second step, the analysis focus on the relationship between parental leave and childcare services in order to develop an overall typology of childcare policies, which clearly shows that many countries display characteristics normally associated with different types (hybrids and. Therefore, this two-step approach enhances our ability to account and make sense of hybrid welfare forms produced from tensions and contradictions within and between policies.

Efficient Blue Electroluminescence Using Quantum-Confined Two-Dimensional Perovskites

Solution-processed hybrid organic–inorganic lead halide perovskites are emerging as one of the most promising candidates for low-cost light-emitting diodes (LEDs). However, due to a small exciton binding energy, it is not yet possible to achieve an efficient electroluminescence within the blue wavelength region at room temperature, as is necessary for full-spectrum light sources. Here, we demonstrate efficient blue LEDs based on the colloidal, quantum-confined 2D perovskites, with precisely controlled stacking down to one-unit-cell thickness (n = 1). A variety of low-k organic host compounds are used to disperse the 2D perovskites, effectively creating a matrix of the dielectric quantum wells, which significantly boosts the exciton binding energy by the dielectric confinement effect. Through the Förster resonance energy transfer, the excitons down-convert and recombine radiatively in the 2D perovskites. We report room-temperature pure green (n = 7–10), sky blue (n = 5), pure blue (n = 3), and deep blue (n = 1) electroluminescence, with record-high external quantum efficiencies in the green-to-blue wavelength region.