Revisiting Clickers: In-Class Questions Followed by At-Home Reflections Are Associated with Higher Student Performance on Related Exam Questions

Clicker questions are a commonly used active learning technique that stimulates student interactions to help advance understanding of key concepts. Clicker questions are often administered with an initial vote, peer discussion, and a second vote, followed by broader classroom explanation. While clickers can promote learning, some studies have questioned whether students maintain this performance on later exams, highlighting the need to further understand how student answer patterns relate to their understanding of the material and to identify ways for clickers to benefit a broader range of students. Systematic requizzing of concepts during at-home assignments represents a promising mechanism to improve student learning. Thus, we paired clicker questions with at-home follow-up reflections to help students articulate and synthesize their understandings. This pairing of clickers with homework allowed us to decipher how student answer patterns related to their underlying conceptions and to determine if revisiting concepts provided additional benefits. We found that students answering both clicker votes correctly performed better on isomorphic exam questions and that students who corrected their answers after the first vote did not show better homework or exam performance than students who maintained an incorrect answer across both votes. Furthermore, completing the followup homework assignment modestly boosted exam question performance. Our data suggest that longer-term benefits of clickers and associated homework may stem from students having repeated opportunities to retrieve, refine, and reinforce emerging conceptions

Hormone replacement therapy is associated with improved survival in women with advanced heart failure

OBJECTIVES: We sought to determine whether hormone replacement therapy (HRT) is associated with an improved prognosis in women with advanced heart failure (HF) and systolic dysfunction. BACKGROUND: There are about two million postmenopausal women in the U.S. with HF. However, limited data are available to assess the effects of HRT on survival in this large group of patients. METHODS: A retrospective analysis of women age 50 years and over entered into the Beta-Blocker Evaluation of Survival Trial (BEST) was conducted using Cox regression analysis comparing survival in HRT users and non-users after correcting for baseline variables known to predict survival in women with HF and systolic dysfunction. RESULTS: In 493 women age 50 years and older, HRT was associated with a significant reduction in mortality-21% mortality in HRT users and 34% in non-users (p = 0.025). Multivariate analysis demonstrated a hazard ratio for mortality of 0.6 (95% confidence interval = 0.36 to 0.97) (p = 0.039) for HRT users. The benefits of HRT were noted only in women with a nonischemic etiology of HF (n = 237). CONCLUSIONS: Hormone replacement therapy is associated with a marked improvement in survival in postmenopausal women with advanced HF. A prospective, randomized trial of HRT should be performed in this large group of patients

Mitochondrial respiration - an important therapeutic target in melanoma

The importance of mitochondria as oxygen sensors as well as producers of ATP and reactive oxygen species (ROS) has recently become a focal point of cancer research. However, in the case of melanoma, little information is available to what extent cellular bioenergetics processes contribute to the progression of the disease and related to it, whether oxidative phosphorylation (OXPHOS) has a prominent role in advanced melanoma. In this study we demonstrate that compared to melanocytes, metastatic melanoma cells have elevated levels of OXPHOS. Furthermore, treating metastatic melanoma cells with the drug, Elesclomol, which induces cancer cell apoptosis through oxidative stress, we document by way of stable isotope labeling with amino acids in cell culture (SILAC) that proteins participating in OXPHOS are downregulated. We also provide evidence that melanoma cells with high levels of glycolysis are more resistant to Elesclomol. We further show that Elesclomol upregulates hypoxia inducible factor 1-α (HIF-1α), and that prolonged exposure of melanoma cells to this drug leads to selection of melanoma cells with high levels of glycolysis. Taken together, our findings suggest that molecular targeting of OXPHOS may have efficacy for advanced melanoma. © 2012 Barbi de Moura et al

Notes on the use and interpretation of radiostereometric analysis

ABSTRACT With increasing numbers of research groups carrying out radiostereometric analysis (RSA), it is important to reach a consensus on how the main aspects of the technique should be carried out and how the results should be presented in an appropriate and consistent way

Phase II trial of the regulatory T cell-depleting agent, denileukin diftitox, in patients with unresectable stage IV melanoma

<p>Abstract</p> <p>Background</p> <p>We previously found that administration of an interleukin 2/diphtheria toxin conjugate (DAB/IL2; Denileukin Diftitox; ONTAK) to stage IV melanoma patients depleted CD4⁺CD25^HIFoxp3⁺regulatory T cells and expanded melanoma-specific CD8⁺T cells. The goal of this study was to assess the clinical efficacy of DAB/IL2 in an expanded cohort of stage IV melanoma patients.</p> <p>Methods</p> <p>In a single-center, phase II trial, DAB/IL2 (12 μg/kg; 4 daily doses; 21 day cycles) was administered to 60 unresectable stage IV melanoma patients and response rates were assessed using a combination of 2-[¹⁸F]-fluoro-2-deoxy-glucose (FDG)-positron emission tomography (PET) and computed tomography (CT) imaging.</p> <p>Results</p> <p>After DAB/IL2 administration, 16.7% of the 60 patients had partial responses, 5% stable disease and 15% mixed responses. Importantly, 45.5% of the chemo/immuno-naïve sub-population (11/60 patients) experienced partial responses. One year survival was markedly higher in partial responders (80 ± 11.9%) relative to patients with progressive disease (23.7 ± 6.5%; <it>p </it>value < 0.001) and 40 ± 6.2% of the total DAB/IL2-treated population were alive at 1 year.</p> <p>Conclusions</p> <p>These data support the development of multi-center, randomized trials of DAB/IL2 as a monotherapy and in combination with other immunotherapeutic agents for the treatment of stage IV melanoma.</p> <p>Trial registration</p> <p><a href="http://www.clinicaltrials.gov/ct2/show/NCT00299689">NCT00299689</a></p

Infektionsabwehr und lymphatischer Rachenring

Foraging behaviours used by two female Australian fur seals (Arctocephalus pusillus doriferus) were documented during controlled feeding trials. During these trials the seals were presented with prey either free-floating in open water or concealed within a mobile ball or a static box feeding device. When targeting free-floating prey both subjects primarily used raptorial biting in combination with suction, which was used to draw prey to within range of the teeth. When targeting prey concealed within either the mobile or static feeding device, the seals were able to use suction to draw out prey items that could not be reached by biting. Suction was followed by lateral water expulsion, where water drawn into the mouth along with the prey item was purged via the sides of the mouth. Vibrissae were used to explore the surface of the feeding devices, especially when locating the openings in which the prey items had been hidden. The mobile ball device was also manipulated by pushing it with the muzzle to knock out concealed prey, which was not possible when using the static feeding device. To knock prey out of this static device one seal used targeted bubble blowing, where a focused stream of bubbles was blown out of the nose into the openings in the device. Once captured in the jaws, prey items were manipulated and re-oriented using further mouth movements or chews so that they could be swallowed head first. While most items were swallowed whole underwater, some were instead taken to the surface and held in the teeth, while being vigorously shaken to break them into smaller pieces before swallowing. The behavioural flexibility displayed by Australian fur seals likely assists in capturing and consuming the extremely wide range of prey types that are targeted in the wild, during both benthic and epipelagic foraging

Coverage, Adherence and Costs of Intermittent Preventive Treatment of Malaria in Children Employing Different Delivery Strategies in Jasikan, Ghana

BACKGROUND: Intermittent preventive treatment of malaria in children (IPTc) involves the administration of a course of anti-malarial drugs at specified time intervals to children at risk of malaria regardless of whether or not they are known to be infected. IPTc provides a high level of protection against uncomplicated and severe malaria, with monthly sulphadoxine-pyrimethamine plus amodiaquine (SP&AQ) and sulphadoxine-pyrimethamine plus piperaquine being the most efficacious regimens. A key challenge is the identification of a cost-effective delivery strategy. METHODS: A community randomized trial was undertaken in Jasikan district, Ghana to assess IPTc effectiveness and costs using SP&AQ delivered in three different ways. Twelve villages were randomly selected to receive IPTc from village health workers (VHWs) or facility-based nurses working at health centres' outpatient departments (OPD) or EPI outreach clinics. Children aged 3 to 59 months-old received one IPT course (three doses) in May, June, September and October. Effectiveness was measured in terms of children covered and adherent to a course and delivery costs were calculated in financial and economic terms using an ingredient approach from the provider perspective. RESULTS: The economic cost per child receiving at least the first dose of all 4 courses was US$4.58 when IPTc was delivered by VHWs, US$4.93 by OPD nurses and US$5.65 by EPI nurses. The unit economic cost of receiving all 3 doses of all 4 courses was US$7.56 and US$8.51 when IPTc was delivered by VHWs or facility-based nurses respectively. The main cost driver for the VHW delivery was supervision, reflecting resources used for travelling to more remote communities rather than more intense supervision, and for OPD and EPI delivery, it was the opportunity cost of the time spent by nurses in dispensing IPTc. CONCLUSIONS: VHWs achieve higher IPTc coverage and adherence at lower costs than facility-based nurses in Jasikan district, Ghana. TRIAL REGISTRATION: ClinicalTrials.gov NCT00119132

Expressions 1990

https://openspace.dmacc.edu/expressions/1012/thumbnail.jp

Modulation of SOCS protein expression influences the interferon responsiveness of human melanoma cells

<p>Abstract</p> <p>Background</p> <p>Endogenously produced interferons can regulate the growth of melanoma cells and are administered exogenously as therapeutic agents to patients with advanced cancer. We investigated the role of negative regulators of interferon signaling known as suppressors of cytokine signaling (SOCS) in mediating interferon-resistance in human melanoma cells.</p> <p>Methods</p> <p>Basal and interferon-alpha (IFN-α) or interferon-gamma (IFN-γ)-induced expression of SOCS1 and SOCS3 proteins was evaluated by immunoblot analysis in a panel of n = 10 metastatic human melanoma cell lines, in human embryonic melanocytes (HEM), and radial or vertical growth phase melanoma cells. Over-expression of SOCS1 and SOCS3 proteins in melanoma cells was achieved using the PINCO retroviral vector, while siRNA were used to inhibit SOCS1 and SOCS3 expression. Tyr⁷⁰¹-phosphorylated STAT1 (P-STAT1) was measured by intracellular flow cytometry and IFN-stimulated gene expression was measured by Real Time PCR.</p> <p>Results</p> <p>SOCS1 and SOCS3 proteins were expressed at basal levels in melanocytes and in all melanoma cell lines examined. Expression of the SOCS1 and SOCS3 proteins was also enhanced following stimulation of a subset of cell lines with IFN-α or IFN-γ. Over-expression of SOCS proteins in melanoma cell lines led to significant inhibition of Tyr⁷⁰¹-phosphorylated STAT1 (P-STAT1) and gene expression following stimulation with IFN-α (IFIT2, OAS-1, ISG-15) or IFN-γ (IRF1). Conversely, siRNA inhibition of SOCS1 and SOCS3 expression in melanoma cells enhanced their responsiveness to interferon stimulation.</p> <p>Conclusions</p> <p>These data demonstrate that SOCS proteins are expressed in human melanoma cell lines and their modulation can influence the responsiveness of melanoma cells to IFN-α and IFN-γ.</p