Observations on the intertidal barnacles (Cirripedia: Balanomorpha) at Fossil Island, Tasman Peninsula: physical tolerances, orientation and fertilisation

Six species of barnacle are found intertidally at Fossil Island. Tolerances of the species to desiccation and temperature could be related to their position on the shore. The four common species all show significant orientation to water currents: in Catornerus polyrnerus the orientation is reversed lower on the shore. Strong evidence is presented that isolated C. polyrnerus individuals can self-fertilise

Evaluating Active U: an Internet-mediated physical activity program.

Background: Engaging in regular physical activity can be challenging, particularly during the winter months. To promote physical activity at the University of Michigan during the winter months, an eight-week Internet-mediated program (Active U) was developed providing participants with an online physical activity log, goal setting, motivational emails, and optional team participation and competition. Methods: This study is a program evaluation of Active U. Approximately 47,000 faculty, staff, and graduate students were invited to participate in the online Active U intervention in the winter of 2007. Participants were assigned a physical activity goal and were asked to record each physical activity episode into the activity log for eight weeks. Statistics for program reach, effectiveness, adoption, and implementation were calculated using the Re-Aim framework. Multilevel regression analyses were used to assess the decline in rates of data entry and goal attainment during the program, to assess the likelihood of joining a team by demographic characteristics, to test the association between various predictors and the number of weeks an individual met his or her goal, and to analyze server load. Results: Overall, 7,483 individuals registered with the Active U website (≈16% of eligible), and 79% participated in the program by logging valid data at least once. Staff members, older participants, and those with a BMI < 25 were more likely to meet their weekly physical activity goals, and average rate of meeting goals was higher among participants who joined a competitive team compared to those who participated individually (IRR = 1.28, P < .001). Conclusion: Internet-mediated physical activity interventions that focus on physical activity logging and goal setting while incorporating team competition may help a significant percentage of the target population maintain their physical activity during the winter months

The developmental dynamics of terrorist organizations

We identify robust statistical patterns in the frequency and severity of violent attacks by terrorist organizations as they grow and age. Using group-level static and dynamic analyses of terrorist events worldwide from 1968-2008 and a simulation model of organizational dynamics, we show that the production of violent events tends to accelerate with increasing size and experience. This coupling of frequency, experience and size arises from a fundamental positive feedback loop in which attacks lead to growth which leads to increased production of new attacks. In contrast, event severity is independent of both size and experience. Thus larger, more experienced organizations are more deadly because they attack more frequently, not because their attacks are more deadly, and large events are equally likely to come from large and small organizations. These results hold across political ideologies and time, suggesting that the frequency and severity of terrorism may be constrained by fundamental processes.Comment: 28 pages, 8 figures, 4 tables, supplementary materia

A powerful method for detecting differentially expressed genes from GeneChip arrays that does not require replicates

BACKGROUND: Studies of differential expression that use Affymetrix GeneChip arrays are often carried out with a limited number of replicates. Reasons for this include financial considerations and limits on the available amount of RNA for sample preparation. In addition, failed hybridizations are not uncommon leading to a further reduction in the number of replicates available for analysis. Most existing methods for studying differential expression rely on the availability of replicates and the demand for alternative methods that require few or no replicates is high. RESULTS: We describe a statistical procedure for performing differential expression analysis without replicates. The procedure relies on a Bayesian integrated approach (BGX) to the analysis of Affymetrix GeneChips. The BGX method estimates a posterior distribution of expression for each gene and condition, from a simultaneous consideration of the available probe intensities representing the gene in a condition. Importantly, posterior distributions of expression are obtained regardless of the number of replicates available. We exploit these posterior distributions to create ranked gene lists that take into account the estimated expression difference as well as its associated uncertainty. We estimate the proportion of non-differentially expressed genes empirically, allowing an informed choice of cut-off for the ranked gene list, adapting an approach proposed by Efron. We assess the performance of the method, and compare it to those of other methods, on publicly available spike-in data sets, as well as in a proper biological setting. CONCLUSION: The method presented is a powerful tool for extracting information on differential expression from GeneChip expression studies with limited or no replicates

MicroRNA-184 Is Induced By Store-Operated Calcium Entry And Regulates Early Keratinocyte Differentiation

Extracellular calcium (Ca2+) and store‐operated Ca2+ entry (SOCE) govern homoeostasis in the mammalian epidermis. Multiple microRNAs (miRNA) also regulate epidermal differentiation, and raised external Ca2+ modulates the expression of several such miRNAs in keratinocytes. However, little is known about the regulation of miR‐184 in keratinocytes or the roles of miR‐184 in keratinocyte differentiation. Here we report that exogenous Ca2+ stimulates miR‐184 expression in primary epidermal keratinocytes and that this occurs in a SOCE‐dependent manner. Levels of miR‐184 were raised by about 30‐fold after exposure to 1.5 mM Ca2+ for 5 days. In contrast, neither phorbol ester nor 1,25‐dihydroxyvitamin D3 had any effect on miR‐184 levels. Pharmacologic and genetic inhibitors of SOCE abrogated Ca2+‐dependent miR‐184 induction by 70% or more. Ectopic miR‐184 inhibited keratinocyte proliferation and led to a fourfold increase in the expression of involucrin, a marker of early keratinocyte differentiation. Exogenous miR‐184 also triggered a threefold rise in levels of cyclin E and doubled the levels of γH2AX, a marker of DNA double‐strand breaks. The p21 cyclin‐dependent kinase inhibitor, which supports keratinocyte growth arrest, was also induced by miR‐184. Together our findings point to an SOCE:miR‐184 pathway that targets a cyclin E/DNA damage regulatory node to facilitate keratinocyte differentiation

Expression of CD33 is a predictive factor for effect of gemtuzumab ozogamicin at different doses in adult acute myeloid leukaemia

It remains unclear in adult acute myeloid leukaemia (AML) whether leukaemic expression of CD33, the target antigen for gemtuzumab ozogamicin (GO), adds prognostic information on GO effectiveness at different doses. CD33 expression quantified in 1583 patients recruited to UK-NCRI-AML17 (younger adults) and UK-NCRI-AML16 (older adults) trials was correlated with clinical outcomes and benefit from GO including a dose randomisation. CD33 expression associated with genetic subgroups, including lower levels in both adverse karyotype and core-binding factor (CBF)-AML, but was not independently prognostic. When comparing GO versus no GO (n=393, CBF-AMLs excluded) by stratified subgroup-adjusted analysis, patients with lowest quartile (Q1) Í33-positivity had no benefit from GO (relapse risk, HR 2.41 (1.27–4.56), P=0.009 for trend; overall survival, HR 1.52 (0.92–2.52)). However, from the dose randomisation (NCRI-AML17, n=464, CBF-AMLs included), 6 mg/m2 GO only had a relapse benefit without increased early mortality in CD33-low (Q1) patients (relapse risk HR 0.64 (0.36–1.12) versus 1.70 (0.99–2.92) for CD33-high, P=0.007 for trend). Thus CD33 expression is a predictive factor for GO effect in adult AML; although GO does not appear to benefit the non-CBF AML patients with lowest CD33 expression a higher GO dose may be more effective for CD33-low but not CD33-high younger adults

Impact of lenalidomide dose on progression-free survival in patients with relapsed or refractory multiple myeloma

This analysis assessed the effect of lenalidomide on progression-free survival (PFS). Patients with relapsed or refractory multiple myeloma (RRMM) who received lenalidomide plus dexamethasone in the MM-009 and MM-010 trials were pooled and those who had not progressed and were still receiving lenalidomide at 12 months were included. The median follow-up of surviving patients was 48 months. Of 353 patients who received lenalidomide plus dexamethasone, 116 (33%) had not progressed. Overall, 52 patients (45%) had no dose reductions, 25 (22%) had dose reductions ⩾12 months and 39 (34%) had dose reductions before 12 months. Patients who had dose reductions ⩾12 months had a significantly longer median PFS than those who had reductions before 12 months (P=0.007) or no dose reductions (P=0.039) (not reached vs 28.0 vs 36.8 months, respectively). In a multivariate Cox regression model, dose reduction ⩾12 months was an independent predictor of improved PFS (hazard ratio, 0.47; 95% confidence interval, 0.23–0.98) after adjusting for patient characteristics. The data suggest that to achieve maximum PFS benefit, patients with RRMM should be treated for ⩾12 months with full-dose lenalidomide plus dexamethasone. Thereafter, patients may benefit from lower-dose continued therapy; prospective studies are needed to confirm these findings

Mutations in protocadherin 15 and cadherin 23 affect tip links and mechanotransduction in mammalian sensory hair cells

Immunocytochemical studies have shown that protocadherin-15 (PCDH15) and cadherin-23 (CDH23) are associated with tip links, structures thought to gate the mechanotransducer channels of hair cells in the sensory epithelia of the inner ear. The present report describes functional and structural analyses of hair cells from Pcdh15av3J (av3J), Pcdh15av6J (av6J) and Cdh23v2J (v2J) mice. The av3J and v2J mice carry point mutations that are predicted to introduce premature stop codons in the transcripts for Pcdh15 and Cdh23, respectively, and av6J mice have an in-frame deletion predicted to remove most of the 9th cadherin ectodomain from PCDH15. Severe disruption of hair-bundle morphology is observed throughout the early-postnatal cochlea in av3J/av3J and v2J/v2J mice. In contrast, only mild-to-moderate bundle disruption is evident in the av6J/av6J mice. Hair cells from av3J/av3J mice are unaffected by aminoglycosides and fail to load with [3H]-gentamicin or FM1-43, compounds that permeate the hair cell's mechanotransducer channels. In contrast, hair cells from av6J/av6J mice load with both FM1-43 and [3H]-gentamicin, and are aminoglycoside sensitive. Transducer currents can be recorded from hair cells of all three mutants but are reduced in amplitude in all mutants and have abnormal directional sensitivity in the av3J/av3J and v2J/v2J mutants. Scanning electron microscopy of early postnatal cochlear hair cells reveals tip-link like links in av6J/av6J mice, substantially reduced numbers of links in the av3J/av3J mice and virtually none in the v2J/v2J mice. Analysis of mature vestibular hair bundles reveals an absence of tip links in the av3J/av3J and v2J/v2J mice and a reduction in av6J/av6J mice. These results therefore provide genetic evidence consistent with PCDH15 and CDH23 being part of the tip-link complex and necessary for normal mechanotransduction