The stellar and sub-stellar IMF of simple and composite populations

The current knowledge on the stellar IMF is documented. It appears to become top-heavy when the star-formation rate density surpasses about 0.1Msun/(yr pc^3) on a pc scale and it may become increasingly bottom-heavy with increasing metallicity and in increasingly massive early-type galaxies. It declines quite steeply below about 0.07Msun with brown dwarfs (BDs) and very low mass stars having their own IMF. The most massive star of mass mmax formed in an embedded cluster with stellar mass Mecl correlates strongly with Mecl being a result of gravitation-driven but resource-limited growth and fragmentation induced starvation. There is no convincing evidence whatsoever that massive stars do form in isolation. Various methods of discretising a stellar population are introduced: optimal sampling leads to a mass distribution that perfectly represents the exact form of the desired IMF and the mmax-to-Mecl relation, while random sampling results in statistical variations of the shape of the IMF. The observed mmax-to-Mecl correlation and the small spread of IMF power-law indices together suggest that optimally sampling the IMF may be the more realistic description of star formation than random sampling from a universal IMF with a constant upper mass limit. Composite populations on galaxy scales, which are formed from many pc scale star formation events, need to be described by the integrated galactic IMF. This IGIMF varies systematically from top-light to top-heavy in dependence of galaxy type and star formation rate, with dramatic implications for theories of galaxy formation and evolution.Comment: 167 pages, 37 figures, 3 tables, published in Stellar Systems and Galactic Structure, Vol.5, Springer. This revised version is consistent with the published version and includes additional references and minor additions to the text as well as a recomputed Table 1. ISBN 978-90-481-8817-

Traditional Roles in a Non‐Traditional Setting: Genetic Counseling in Precision Oncology

Next generation sequencing technology is increasingly utilized in oncology with the goal of targeting therapeutics to improve response and reduce side effects. Interpretation of tumor mutations requires sequencing of paired germline DNA, raising questions about incidental germline findings. We describe our experiences as part of a research team implementing a protocol for whole genome sequencing (WGS) of tumors and paired germline DNA known as the Michigan Oncology Sequencing project (MI‐ONCOSEQ) that includes options for receiving incidental germline findings. Genetic counselors (GCs) discuss options for return of results with patients during the informed consent process and document family histories. GCs also review germline findings and actively participate in the multi‐disciplinary Precision Medicine Tumor Board (PMTB), providing clinical context for interpretation of germline results and making recommendations about disclosure of germline findings. GCs have encountered ethical and counseling challenges with participants, described here. Although GCs have not been traditionally involved in molecular testing of tumors, our experiences with MI‐ONCOSEQ demonstrate that GCs have important applicable skills to contribute to multi‐disciplinary care teams implementing precision oncology. Broader use of WGS in oncology treatment decision making and American College of Medical Genetics and Genomics (ACMG) recommendations for active interrogation of germline tissue in tumor‐normal dyads suggests that GCs will have future opportunities in this area outside of research settings.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147078/1/jgc40655.pd

Maintenance of response with atypical antipsychotics in the treatment of schizophrenia: a post-hoc analysis of 5 double-blind, randomized clinical trials

<p>Abstract</p> <p>Background</p> <p>How long an antipsychotic is effective in maintaining response is important in choosing the correct treatment for people with schizophrenia. This post-hoc analysis describes maintenance of response over 24 or 28 weeks in people treated for schizophrenia with olanzapine, risperidone, quetiapine, ziprasidone, or aripiprazole.</p> <p>Methods</p> <p>This was a post-hoc analysis using data from 5 double-blind, randomized, comparative trials of 24 or 28 weeks duration in which olanzapine was compared to risperidone (1 study; N = 339), quetiapine (1 study; N = 346), ziprasidone (2 studies; N = 548 and 394) or aripiprazole (1 study; N = 566) for treatment of schizophrenia. For each study, time to loss of response in patients who met criteria for response at Week 8 and the proportion of patients who lost response following Week 8 were compared by treatment group. The number needed to treat (NNT) with olanzapine rather than comparator to avoid loss of one additional responder over 24 or 28 weeks of treatment was calculated for each study.</p> <p>Results</p> <p>Time maintained in response was significantly longer (p < .05) for olanzapine compared to risperidone, quetiapine, and ziprasidone. Olanzapine did not significantly differ from aripiprazole. The proportion of patients who lost response was significantly lower for olanzapine versus risperidone, quetiapine, and ziprasidone (p < .05). NNTs to avoid one additional patient with loss of response with olanzapine versus risperidone, quetiapine and ziprasidone were favourable, ranging from 5 to 9.</p> <p>Conclusion</p> <p>During 24 and 28 weeks of treatment, the antipsychotics studied differed in the time that treated patients with schizophrenia remained in response and the proportion of patients who lost response. Olanzapine treatment resulted in a consistent and statistically significant advantage in maintenance of response compared to treatment with risperidone, quetiapine and ziprasidone; but not compared to treatment with aripiprazole.</p

Identification of QTLs for Arsenic Accumulation in Maize (Zea mays L.) Using a RIL Population

The Arsenic (As) concentration in different tissues of maize was analyzed using a set of RIL populations derived from an elite hybrid, Nongda108. The results showed that the trend of As concentration in the four measured tissues was leaves>stems>bracts>kernels. Eleven QTLs for As concentration were detected in the four tissues. Three QTLs for As concentration in leaves were mapped on chromosomes 1, 5, and 8, respectively. For As concentration in the bracts, two QTLs were identified, with 9.61% and 10.03% phenotypic variance. For As concentration in the stems, three QTLs were detected with 8.24%, 14.86%, and 15.23% phenotypic variance. Three QTLs were identified for kernels on chromosomes 3, 5, and 7, respectively, with 10.73%, 8.52%, and 9.10% phenotypic variance. Only one common chromosomal region between SSR marker bnlg1811 and umc1243 was detected for QTLs qLAV1 and qSAC1. The results implied that the As accumulation in different tissues in maize was controlled by different molecular mechanism. The study demonstrated that maize could be a useful plant for phytoremediation of As-contaminated paddy soil, and the QTLs will be useful for selecting inbred lines and hybrids with low As concentration in their kernels

Phase 2 study of dual VEGF/HER2 blockade with pazopanib + lapatinib in patients with first-line HER2 positive advanced or metastatic (adv/met) breast cancer.

Abstract Abstract #4114 Background: Evidence indicates a direct molecular link between HER2 amplification and up-regulation of VEGF in HER2+ breast cancer. Concurrent over-expression of HER2 and VEGF is associated with a poorer clinical outcome than over-expression of either alone. These data provide the rationale for simultaneous blockade of both pathways. Pazopanib (P) is an oral angiogenesis inhibitor targeting VEGFR, PDGFR, and c-kit. Lapatinib (Tykerb®) (L) is an oral tyrosine kinase inhibitor of EGFR (ErbB1) and HER2 (ErbB2). This study (VEG20007) evaluated the efficacy and safety of dual pathway inhibition in patients (pts) with HER2+ adv/met breast cancer.&amp;#x2028; Methods: Eligible pts received no prior chemotherapy or HER2-directed therapy for met disease and had measurable disease per RECIST. Pts were enrolled in one of 2 cohorts. In cohort 1 (C1), pts were randomized to P 400 mg/d + L 1000 mg/d or L alone (1500 mg/d). Enrollment to cohort 2 (C2) began after completion of enrollment to C1. In C2 pts received the combination at doses of P 800 mg/d and L 1500 mg/d. Following disease assessment at week (wk) 12, pts with an objective response could continue on study treatment following re-consent; those with stable disease could continue only where trastuzumab was unavailable. The primary endpoint of C1 was progressive disease rate (PDR) at wk 12 in HER2 FISH+ pts. The primary endpoint of C2 is week 12 response rate in HER2 FISH+ pts.&amp;#x2028; Results: 140 pts were included in the randomized cohort analysis which was previously reported [J Clin Onc 26:2008 (May 20 suppl; abstr 1016)]. Enrollment in C2 has been completed; 40 pts (36 confirmed FISH+) have been enrolled. A preliminary safety analysis has been performed. The most common adverse events of any grade were diarrhea, nausea, fatigue, hypertension, and rash. The most common laboratory abnormalities were ALT and AST increase. Efficacy data will be analyzed when the last pt has completed the week 12 assessment.&amp;#x2028; Conclusion: This is the first Phase II trial to evaluate the combination of 2 oral targeted agents in first-line Her2+ adv/met breast cancer. The lower dose combination demonstrated improved response rate compared to L monotherapy. Previously unreported efficacy and safety data from the higher dose cohort will be presented. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4114.</jats:p