Cooperative Learning in Science: Follow-up from primary to high school

This paper reports a two-year longitudinal study of the effects of cooperative learning on science attainment, attitudes towards science, and social connectedness during transition from primary to high school. A previous project on cooperative learning in primary schools observed gains in science understanding and in social aspects of school life. This project followed 204 children involved in the previous project and 440 comparison children who were not as they undertook transition from 24 primary schools to 16 high schools. Cognitive, affective, and social gains observed in the original project survived transition. The implications improving the effectiveness of school transition by using cooperative learning initiatives are explored. Possibilities for future research and the implications for practice and policy are discussed.

Clofarabine doubles the response rate in older patients with acute myeloid leukemia but does not improve survival

Better treatment is required for older patients with acute myeloid leukemia (AML) not considered fit for intensive chemotherapy. We report a randomized comparison of lowdose Ara-C (LDAC) vs the novel nucleoside, clofarabine, in untreated older patients with AML and high-risk myelodysplastic syndrome (MDS). A total of 406 patients with de novo (62%), secondary disease (24%), or high-risk MDS (>10% marrow blasts) (15%), median age 74 years, were randomized to LDAC 20 mg twice daily for 10 days every 6 weeks or clofarabine 20 mg/m2 on days 1 to 5, both for up to 4 courses. These patients had more adverse demographics than contemporaneous intensively treated patients. The overall remission rate was 28%, and 2-year survival was 13%. Clofarabine significantly improved complete remission (22% vs 12%; hazard ratio [HR] 5 0.47 [0.28-0.79]; P 5 .005) and overall response (38% vs 19%; HR 5 0.41 [0.26-0.62]; P < .0001), but there was no difference in overall survival, explained by poorer survival in the clofarabine patients who did not gain complete remission and also following relapse. Clofarabine was more myelosuppressive and required more supportive care. Although clofarabine doubled remission rates, overall survival was not improved overall or in any subgroup. The treatment of patients of the type treated here remains a major unmet need. This trial was registered at www.clinicaltrials.gov as #ISRCTN 11036523.

Cathelicidin-like Helminth Defence Molecules (HDMs):Absence of Cytotoxic, Anti-microbial and Anti-protozoan Activities Imply a Specific Adaptation to Immune Modulation

Host defence peptides (HDPs) are expressed throughout the animal and plant kingdoms. They have multifunctional roles in the defence against infectious agents of mammals, possessing both bactericidal and immune-modulatory activities. We have identified a novel family of molecules secreted by helminth parasites (helminth defence molecules; HDMs) that exhibit similar structural and biochemical characteristics to the HDPs. Here, we have analyzed the functional activities of four HDMs derived from Schistosoma mansoni and Fasciola hepatica and compared them to human, mouse, bovine and sheep HDPs. Unlike the mammalian HDPs the helminth-derived HDMs show no antimicrobial activity and are non-cytotoxic to mammalian cells (macrophages and red blood cells). However, both the mammalian- and helminth-derived peptides suppress the activation of macrophages by microbial stimuli and alter the response of B cells to cytokine stimulation. Therefore, we hypothesise that HDMs represent a novel family of HDPs that evolved to regulate the immune responses of their mammalian hosts by retaining potent immune modulatory properties without causing deleterious cytotoxic effects.

Secreted Proteins from the Helminth Fasciola hepatica Inhibit the Initiation of Autoreactive T Cell Responses and Prevent Diabetes in the NOD Mouse

Infections with helminth parasites prevent/attenuate auto-inflammatory disease. Here we show that molecules secreted by a helminth parasite could prevent Type 1 Diabetes (T1D) in nonobese diabetic (NOD) mice. When delivered at 4 weeks of age (coincident with the initiation of autoimmunity), the excretory/secretory products of Fasciola hepatica (FhES) prevented the onset of T1D, with 84% of mice remaining normoglycaemic and insulitis-free at 30 weeks of age. Disease protection was associated with suppression of IFN-γ secretion from autoreactive T cells and a switch to the production of a regulatory isotype (from IgG2a to IgG1) of autoantibody. Following FhES injection, peritoneal macrophages converted to a regulatory M2 phenotype, characterised by increased expression levels of Ym1, Arg-1, TGFβ and PD-L1. Expression of these M2 genetic markers increased in the pancreatic lymph nodes and the pancreas of FhES-treated mice. In vitro, FhES-stimulated M2 macrophages induced the differentiation of Tregs from splenocytes isolated from naïve NOD mice. Collectively, our data shows that FhES contains immune-modulatory molecules that mediate protection from autoimmune diabetes via the induction and maintenance of a regulatory immune environment.

Rare and common variants in extracellular matrix gene Fibrillin 2 (FBN2) are associated with macular degeneration

Neurodegenerative diseases affecting the macula constitute a major cause of incurable vision loss and exhibit considerable clinical and genetic heterogeneity, from early-onset monogenic disease to multifactorial late-onset age-related macular degeneration (AMD). As part of our continued efforts to define genetic causes of macular degeneration, we performed whole exome sequencing in four individuals of a two-generation family with autosomal dominant maculopathy and identified a rare variant p.Glu1144Lys in Fibrillin 2 (FBN2), a glycoprotein of the elastin-rich extracellular matrix (ECM). Sanger sequencing validated the segregation of this variant in the complete pedigree, including two additional affected and one unaffected individual. Sequencing of 192 maculopathy patients revealed additional rare variants, predicted to disrupt FBN2 function. We then undertook additional studies to explore the relationship of FBN2 to macular disease. We show that FBN2 localizes to Bruch's membrane and its expression appears to be reduced in aging and AMD eyes, prompting us to examine its relationship with AMD. We detect suggestive association of a common FBN2 non-synonymous variant, rs154001 (p.Val965Ile) with AMD in 10,337 cases and 11,174 controls (OR=1.10; p-value=3.79×10(-5)). Thus, it appears that rare and common variants in a single gene - FBN2 - can contribute to Mendelian and complex forms of macular degeneration. Our studies provide genetic evidence for a key role of elastin microfibers and Bruch's membrane in maintaining blood-retina homeostasis and establish the importance of studying orphan diseases for understanding more common clinical phenotypes.