398 research outputs found

    Crystal Structure of Human AKT1 with an Allosteric Inhibitor Reveals a New Mode of Kinase Inhibition

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    AKT1 (NP_005154.2) is a member of the serine/threonine AGC protein kinase family involved in cellular metabolism, growth, proliferation and survival. The three human AKT isozymes are highly homologous multi-domain proteins with both overlapping and distinct cellular functions. Dysregulation of the AKT pathway has been identified in multiple human cancers. Several clinical trials are in progress to test the efficacy of AKT pathway inhibitors in treating cancer. Recently, a series of AKT isozyme-selective allosteric inhibitors have been reported. They require the presence of both the pleckstrin-homology (PH) and kinase domains of AKT, but their binding mode has not yet been elucidated. We present here a 2.7 ƅ resolution co-crystal structure of human AKT1 containing both the PH and kinase domains with a selective allosteric inhibitor bound in the interface. The structure reveals the interactions between the PH and kinase domains, as well as the critical amino residues that mediate binding of the inhibitor to AKT1. Our work also reveals an intricate balance in the enzymatic regulation of AKT, where the PH domain appears to lock the kinase in an inactive conformation and the kinase domain disrupts the phospholipid binding site of the PH domain. This information advances our knowledge in AKT1 structure and regulation, thereby providing a structural foundation for interpreting the effects of different classes of AKT inhibitors and designing selective ones

    Towards an analytical framework of science communication models

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    This chapter reviews the discussion in science communication circles of models for public communication of science and technology (PCST). It questions the claim that there has been a large-scale shift from a ā€˜deficit modelā€™ of communication to a ā€˜dialogue modelā€™, and it demonstrates the survival of the deficit model along with the ambiguities of that model. Similar discussions in related fields of communication, including the critique of dialogue, are briefly sketched. Outlining the complex circumstances governing approaches to PCST, the author argues that communications models often perceived to be opposed can, in fact, coexist when the choices are made explicit. To aid this process, the author proposes an analytical framework of communication models based on deficit, dialogue and participation, including variations on each

    Incommensurable worldviews? Is public use of complementary and alternative medicines incompatible with support for science and conventional medicine?

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    Proponents of controversial Complementary and Alternative Medicines, such as homeopathy, argue that these treatments can be used with great effect in addition to, and sometimes instead of, ?conventional? medicine. In doing so, they accept the idea that the scientific approach to the evaluation of treatment does not undermine use of and support for some of the more controversial CAM treatments. For those adhering to the scientific canon, however, such efficacy claims lack the requisite evidential basis from randomised controlled trials. It is not clear, however, whether such opposition characterises the views of the general public. In this paper we use data from the 2009 Wellcome Monitor survey to investigate public use of and beliefs about the efficacy of a prominent and controversial CAM within the United Kingdom, homeopathy. We proceed by using Latent Class Analysis to assess whether it is possible to identify a sub-group of the population who are at ease in combining support for science and conventional medicine with use of CAM treatments, and belief in the efficacy of homeopathy. Our results suggest that over 40% of the British public maintain positive evaluations of both homeopathy and conventional medicine simultaneously. Explanatory analyses reveal that simultaneous support for a controversial CAM treatment and conventional medicine is, in part, explained by a lack of scientific knowledge as well as concerns about the regulation of medical research

    Excitons in a Photosynthetic Light-Harvesting System: A Combined Molecular Dynamics/Quantum Chemistry and Polaron Model Study

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    The dynamics of pigment-pigment and pigment-protein interactions in light-harvesting complexes is studied with a novel approach which combines molecular dynamics (MD) simulations with quantum chemistry (QC) calculations. The MD simulations of an LH-II complex, solvated and embedded in a lipid bilayer at physiological conditions (with total system size of 87,055 atoms) revealed a pathway of a water molecule into the B800 binding site, as well as increased dimerization within the B850 BChl ring, as compared to the dimerization found for the crystal structure. The fluctuations of pigment (B850 BChl) excitation energies, as a function of time, were determined via ab initio QC calculations based on the geometries that emerged from the MD simulations. From the results of these calculations we constructed a time-dependent Hamiltonian of the B850 exciton system from which we determined the linear absorption spectrum. Finally, a polaron model is introduced to describe quantum mechanically both the excitonic and vibrational (phonon) degrees of freedom. The exciton-phonon coupling that enters into the polaron model, and the corresponding phonon spectral function are derived from the MD/QC simulations. It is demonstrated that, in the framework of the polaron model, the absorption spectrum of the B850 excitons can be calculated from the autocorrelation function of the excitation energies of individual BChls, which is readily available from the combined MD/QC simulations. The obtained result is in good agreement with the experimentally measured absorption spectrum.Comment: REVTeX3.1, 23 pages, 13 (EPS) figures included. A high quality PDF file of the paper is available at http://www.ks.uiuc.edu/Publications/Papers/PDF/DAMJ2001/DAMJ2001.pd

    655MO Quality of life in patients with p16+ oropharyngeal cancer receiving accelerated radiotherapy (RT) with either cisplatin or cetuximab in NRG/RTOG 1016

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    Background: This phase 3 randomized non-inferiority de-escalation trial compared cetuximab (cetux) vs cisplatin (cis), concurrent with accelerated RT 70 Gy/6 weeks, in p16+ oropharyngeal cancer (OPC). Quality of life (QOL) was an important secondary endpoint. Methods: EORTC QLQ-C30/HN35 was completed at baseline, end of treatment, 3, 6, and 12 months post. The substudy aimed for 400 eligible patients. We report completion rates and compare by arm for change from baseline in each domain (0.05 two-sided alpha and MID of 10 points) using linear mixed models. Results: Consent was 91% (381/419 offered substudy); 6 protocol deviations excluded (n=375). No significant differences in patient/tumor characteristics were found by participation status. Completion rates (%) at the 5 times did not differ by arm (cis/cetux): 92/94, 74/77, 76/81, 76/81, and 73/74. The swallowing domain of HN35 (previously reported) did not differ significantly by arm. No significant difference was seen by arm for the 6-mo change from baseline on any domain. At end of RT (only), dry mouth was significantly worse for RT+cetux. At end of treatment, all domains showed statistically and clinically significant mean worsening across both arms except Emotional Functioning, Dyspnea, Diarrhea, and Teeth. Most domains returned within 10 points of baseline by 6 mo, with the following maintaining significant impairment: Senses (taste/smell), Social Eating, Opening Mouth, Dry Mouth, Sticky Saliva. At 12 mo post-treatment, worsening from baseline persisted for Senses, Dry Mouth, Sticky Saliva, and Weight Gain. Pain Killer use improved significantly from baseline to 3, 6, and 12 mo. Conclusions: Although replacing RT+cis with RT+cetux did not benefit QOL, this study has confirmed the responsiveness of EORTC QLQ-C30/HN35 to the effects of concurrent systemic/RT for OPC. Dry Mouth, Sticky Saliva, and Senses showed large, significant, and persistent impairments, and remain worthwhile targets for future de-escalation efforts. Domains related to eating (Swallowing, Appetite, Nutritional Supplements, Social Eating, Weight Loss) did not show sustained significant impairment on this instrument in this study. Clinical trial identification: NCT01302834

    Risk and Clinical Risk Factors associated With Late Lower Cranial Neuropathy in Long-Term oropharyngeal Squamous Cell Carcinoma Survivors

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    IMPORTANCE: Lower cranial neuropathy (LCNP) is a rare, but permanent, late effect of radiotherapy and other cancer therapies. Lower cranial neuropathy is associated with excess cancer-related symptoms and worse swallowing-related quality of life. Few studies have investigated risk and clinical factors associated with late LCNP among patients with long-term survival of oropharyngeal squamous cell carcinoma (OPSCC survivors). OBJECTIVE: to estimate the cumulative incidence of and identify clinical factors associated with late LCNP among long-term OPSCC survivors. DESIGN, SETTING, AND PARTICIPANTS: This single-institution cohort study included disease-free adult OPSCC survivors who completed curative treatment from January 1, 2000, to December 31, 2013. Exclusion criteria consisted of baseline LCNP, recurrent head and neck cancer, treatment at other institutions, death, and a second primary, persistent, or recurrent malignant neoplasm of the head and neck less than 3 months after treatment. Median survival of OPSCC among the 2021 eligible patients was 6.8 (range, 0.3-18.4) years. Data were analyzed from October 12, 2019, to November 13, 2020. MAIN OUTCOMES AND MEASURES: Late LCNP events were defined by neuropathy of the glossopharyngeal, vagus, and/or hypoglossal cranial nerves at least 3 months after cancer therapy. Cumulative incidence of LCNP was estimated using the Kaplan-Meier method, and multivariable Cox proportional hazards models were fit. RESULTS: Among the 2021 OPSCC survivors included in the analysis of this cohort study (1740 [86.1%] male; median age, 56 [range, 28-86] years), 88 (4.4%) were diagnosed with late LCNP, with median time to LCNP of 5.4 (range, 0.3-14.1) years after treatment. Cumulative incidence of LCNP was 0.024 (95% CI, 0.017-0.032) at 5 years, 0.061 (95% CI, 0.048-0.078) at 10 years, and 0.098 (95% CI, 0.075-0.128) at 15 years of follow-up. Multivariable Cox proportional hazards regression identified T4 vs T1 classification (hazard ratio [HR], 3.82; 95% CI, 1.85-7.86) and accelerated vs standard radiotherapy fractionation (HR, 2.15; 95% CI, 1.34-3.45) as independently associated with late LCNP status, after adjustment. Among the subgroup of 1986 patients with nonsurgical treatment, induction chemotherapy regimens including combined docetaxel, cisplatin, and fluorouracil (TPF) (HR, 2.51; 95% CI, 1.35-4.67) and TPF with cetuximab (HR, 5.80; 95% CI, 1.74-19.35) along with T classification and accelerated radiotherapy fractionation were associated with late LCNP status after adjustment. CONCLUSIONS AND RELEVANCE: This single-institution cohort study found that, although rare in the population overall, cumulative risk of late LCNP progressed to 10% during the survivors\u27 lifetime. As expected, clinical factors associated with LCNP primarily reflected greater tumor burden and treatment intensity. Further efforts are necessary to investigate risk-reduction strategies as well as surveillance and management strategies for this disabling late effect of cancer treatment

    Ursinus College Alumni Journal, August 1963

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    The President writes ā€¢ The uses and limitations of words ā€¢ Commencement 1963 ā€¢ 3,032 pledge 509,081;2,809contribute509,081; 2,809 contribute 192,568 ā€¢ Loyalty Fund committee reorganized ā€¢ Joseph J. Lynch, college steward ā€¢ A description of the new dining hall ā€¢ Chemistry changes ā€¢ NSF grants for bio profs ā€¢ Teaching awards ā€¢ Pilot project: Physics chemistry mathematics ā€¢ The not-so-ugly American ā€¢ Best track season in Ursinus history ā€¢ Double your dollars ā€¢ Things are looking up ā€¢ Preliminary thoughts on wills ā€¢ Reading, writing, and Mazurkiewicz ā€¢ The augmented Roman alphabet ā€¢ Edwin C. Myers, \u2764 and Frederic W. Yocum, Jr. \u2764 ā€¢ Eugene J. Bradford, \u2736 ā€¢ Robert A. Petersen, \u2760 ā€¢ Sue Harman, \u2765 ā€¢ Results of the 1963 Loyalty Fund campaign ā€¢ The leaders ā€¢ Contributors to the 1963 Loyalty Fund ā€¢ Ursinus alumni at Methacton High School ā€¢ Class notes ā€¢ Weddings ā€¢ Births ā€¢ Necrology ā€¢ Our role as alumnihttps://digitalcommons.ursinus.edu/alumnijournal/1077/thumbnail.jp

    Making sense of policy choices: understanding the roles of value predispositions, mass media, and cognitive processing in public attitudes toward nanotechnology

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    Using a nationally representative telephone survey of 1,015 adults in the United States, this study examines how value predispositions, communication variables, and perceptions of risks and benefits are associated with public support for federal funding of nanotechnology. Our findings show that highly religious individuals were less supportive of funding of nanotech than less religious individuals, whereas individuals who held a high deference for scientific authority were more supportive of funding of the emerging technology than those low in deference. Mass media use and elaborative processing of scientific news were positively associated with public support for funding, whereas factual scientific knowledge had no significant association with policy choices. The findings suggest that thinking about and reflecting upon scientific news promote better understanding of the scientific world and may provide a more sophisticated cognitive structure for the public to form opinions about nanotech than factual scientific knowledge. Finally, heuristic cues including trust in scientists and perceived risks and benefits of nanotech were found to be associated with public support for nanotech funding. We conclude with policy implications that will be useful for policymakers and science communication practitioners

    Case report: The management of advanced oral cancer in a Jehovah's Witness using the Ultracision Harmonic Scalpel

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    We present the first case of a head and neck oncological procedure accomplished in a Jehovah's Witness using the Ultracision Harmonic Scalpel (Ethicon, Cincinnati, OH). Jehovah's Witnesses present a serious challenge to the head and neck cancer surgeon due to their refusal to accept transfusion of any blood products. However, our experience reinforces the view that surgical management of head and neck cancer is possible in these patients. We show the Harmonic Scalpel, an ultrasonic tissue dissector, to be a useful surgical tool in obviating the need for blood transfusion. Preoperative optimisation, intra-operative surgical and anaesthetic techniques are also fully discussed
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