660 research outputs found

    Trends in opioid use over time: 1997 to 1999

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    Substantial resources have been spent to improve pain control for dying patients, and increased opioid administration has been presumed. Oregon has been a consistent leading state in per capita use for morphine for the past 10 years, as recorded by the Automation of Reports and Consolidated Orders System (ARCOS). Health policy experts, extrapolating from World Health Organization methods, have suggested these data are indicative of the quality of end-of-life care in Oregon. To determine whether trends in opioid prescription at the state and national levels reflect increased opioid use for inpatients during the final week of life, chart reviews were conducted to record all opioid medications administered in the last week of life to 877 adult inpatients who died from natural causes between January 1, 1997 and December 31, 1999. Inpatient morphine use did not increase significantly for dying patients from 1997 to 1999. However, overall morphine use for both Oregon and the United States as measured by ARCOS data increased significantly. Comparisons revealed no significant difference between linear trends for Oregon and U.S. morphine use, but both were significantly greater than the dying inpatients. This pattern was also found for all other opioids. These findings suggest that ARCOS data do not necessarily provide information about opioid use for specific subpopulations of patients and raise questions about the meaning of observed increases in ARCOS data

    DNA binding shifts the redox potential of the transcription factor SoxR

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    Electrochemistry measurements on DNA-modified electrodes are used to probe the effects of binding to DNA on the redox potential of SoxR, a transcription factor that contains a [2Fe-2S] cluster and is activated through oxidation. A DNA-bound potential of +200 mV versus NHE (normal hydrogen electrode) is found for SoxR isolated from Escherichia coli and Pseudomonas aeruginosa. This potential value corresponds to a dramatic shift of +490 mV versus values found in the absence of DNA. Using Redmond red as a covalently bound redox reporter affixed above the SoxR binding site, we also see, associated with SoxR binding, an attenuation in the Redmond red signal compared with that for Redmond red attached below the SoxR binding site. This observation is consistent with a SoxR-binding-induced structural distortion in the DNA base stack that inhibits DNA-mediated charge transport to the Redmond red probe. The dramatic shift in potential for DNA-bound SoxR compared with the free form is thus reconciled based on a high-energy conformational change in the SoxR–DNA complex. The substantial positive shift in potential for DNA-bound SoxR furthermore indicates that, in the reducing intracellular environment, DNA-bound SoxR is primarily in the reduced form; the activation of DNA-bound SoxR would then be limited to strong oxidants, making SoxR an effective sensor for oxidative stress. These results more generally underscore the importance of using DNA electrochemistry to determine DNA-bound potentials for redox-sensitive transcription factors because such binding can dramatically affect this key protein property

    Adherence and Concordance between Serious Illness Care Planning Conversations and Oncology Clinician Documentation among Patients with Advanced Cancer

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    Background:Serious illness conversations are part of advance care planning (ACP) and focus on prognosis, values, and goals in patients who are seriously ill. To be maximally effective, such conversations must be documented accurately and be easily accessible. Objectives:The two coprimary objectives of the study were to assess concordance between written documentation and recorded audiotaped conversations, and to evaluate adherence to the Serious Illness Conversation Guide questions. Methods:Data were obtained as part of a trial in patients with advanced cancer. Clinicians were trained to use a guide to conduct and document serious illness conversations. Conversations were audiotaped. Two researchers independently compared audiorecordings with the corresponding documentation in an electronic health record (EHR) template and free-text progress notes, and rated the degree of concordance and adherence. Results:We reviewed a total of 25 audiorecordings. Clinicians addressed 87% of the conversation guide elements. Prognosis was discussed least frequently, only in 55% of the patients who wanted that information. Documentation was fully concordant with the conversation 43% of the time. Concordance was best when documenting family matters and goals, and least frequently concordant when documenting prognostic communication. Most conversations (64%) were documented in the template, a minority (28%) only in progress notes and two conversations (8%) were not documented. Concordance was better when the template was used (62% vs. 28%). Conclusion:Clinicians adhered well to the conversation guide. However, key information elicited was documented and fully concordant less than half the time. Greater concordance was observed when clinicians used a prespecified template. The combined use of a guide and EHR template holds promise for ACP conversations

    A Qualitative Study of Serious Illness Conversations in Patients with Advanced Cancer

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    BACKGROUND: Conversations with seriously ill patients about their values and goals have been associated with reduced distress, a better quality of life, and goal-concordant care near the end of life. Yet, little is known about how such conversations are conducted. OBJECTIVE: To characterize the content of serious illness conversations and identify opportunities for improvement. DESIGN: Qualitative analysis of audio-recorded, serious illness conversations using an evidence-based guide and obtained through a cluster randomized controlled trial in an outpatient oncology setting. Setting/Measurements: Clinicians assigned to the intervention arm received training to use the "Serious Illness Conversation Guide" to have a serious illness conversation about values and goals with advanced cancer patients. Conversations were de-identified, transcribed verbatim, and independently coded by two researchers. Key themes were analyzed. RESULTS: A total of 25 conversations conducted by 16 clinicians were evaluated. The median conversation duration was 14 minutes (range 4-37), with clinicians speaking half of the time. Thematic analyses demonstrated five key themes: (1) supportive dialogue between patients and clinicians; (2) patients' openness to discuss emotionally challenging topics; (3) patients' willingness to articulate preferences regarding life-sustaining treatments; (4) clinicians' difficulty in responding to emotional or ambiguous patient statements; and (5) challenges in discussing prognosis. CONCLUSIONS: Data from this exploratory study suggest that seriously ill patients are open to discussing values and goals with their clinician. Yet, clinicians may struggle when disclosing a time-based prognosis and in responding to patients' emotions. Such skills should be a focus for additional training for clinicians caring for seriously ill patients

    Self-assembled photosystem-I biophotovoltaics on nanostructured TiO2 and ZnO

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    The abundant pigment-protein membrane complex photosystem-I (PS-I) is at the heart of the Earth’s energy cycle. It is the central molecule in the “Z-scheme” of photosynthesis, converting sunlight into the chemical energy of life. Commandeering this intricately organized photosynthetic nanocircuitry and re-wiring it to produce electricity carries the promise of inexpensive and environmentally friendly solar power. We here report that dry PS-I stabilized by surfactant peptides functioned as both the light-harvester and charge separator in solar cells self-assembled on nanostructured semiconductors. Contrary to previous attempts at biophotovoltaics requiring elaborate surface chemistries, thin film deposition, and illumination concentrated into narrow wavelength ranges the devices described here are straightforward and inexpensive to fabricate and perform well under standard sunlight yielding open circuit photovoltage of 0.5 V, fill factor of 71%, electrical power density of 81 µW/cm2 and photocurrent density of 362 µA/cm2, over four orders of magnitude higher than any photosystem-based biophotovoltaic to date

    Atomic structure of granulin determined from native nanocrystalline granulovirus using an X-ray free-electron laser

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    To understand how molecules function in biological systems, new methods are required to obtain atomic resolution structures from biological material under physiological conditions. Intense femtosecond-duration pulses from X-ray free-electron lasers (XFELs) can outrun most damage processes, vastly increasing the tolerable dose before the specimen is destroyed. This in turn allows structure determination from crystals much smaller and more radiation sensitive than previously considered possible, allowing data collection from room temperature structures and avoiding structural changes due to cooling. Regardless, high-resolution structures obtained from XFEL data mostly use crystals far larger than 1 ÎĽm3 in volume, whereas the X-ray beam is often attenuated to protect the detector from damage caused by intense Bragg spots. Here, we describe the 2 Ă… resolution structure of native nanocrystalline granulovirus occlusion bodies (OBs) that are less than 0.016 ÎĽm3 in volume using the full power of the Linac Coherent Light Source (LCLS) and a dose up to 1.3 GGy per crystal. The crystalline shell of granulovirus OBs consists, on average, of about 9,000 unit cells, representing the smallest protein crystals to yield a high-resolution structure by X-ray crystallography to date. The XFEL structure shows little to no evidence of radiation damage and is more complete than a model determined using synchrotron data from recombinantly produced, much larger, cryocooled granulovirus granulin microcrystals. Our measurements suggest that it should be possible, under ideal experimental conditions, to obtain data from protein crystals with only 100 unit cells in volume using currently available XFELs and suggest that single-molecule imaging of individual biomolecules could almost be within reach

    Multibudded tubules formed by COPII on artificial liposomes

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    COPII-coated vesicles form at the endoplasmic reticulum for cargo transport to the Golgi apparatus. We used in vitro reconstitution to examine the roles of the COPII scaffold in remodeling the shape of a lipid bilayer. Giant Unilamellar Vesicles were examined using fast confocal fluorescence and cryo-electron microscopy in order to avoid separation steps and minimize mechanical manipulation. COPII showed a preference for high curvature structures, but also sufficient flexibility for binding to low curvatures. The COPII proteins induced beads-on-a-string-like constricted tubules, similar to those previously observed in cells. We speculate about a mechanical pathway for vesicle fission from these multibudded COPII-coated tubules, considering the possibility that withdrawal of the Sar1 amphipathic helix upon GTP hydrolysis leads to lipid bilayer destabilization resulting in fission

    Decoupling property of the supersymmetric Higgs sector with four doublets

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    In supersymmetric standard models with multi Higgs doublet fields, selfcoupling constants in the Higgs potential come only from the D-terms at the tree level. We investigate the decoupling property of additional two heavier Higgs doublet fields in the supersymmetric standard model with four Higgs doublets. In particular, we study how they can modify the predictions on the quantities well predicted in the minimal supersymmetric standard model (MSSM), when the extra doublet fields are rather heavy to be measured at collider experiments. The B-term mixing between these extra heavy Higgs bosons and the relatively light MSSM-like Higgs bosons can significantly change the predictions in the MSSM such as on the masses of MSSM-like Higgs bosons as well as the mixing angle for the two light CP-even scalar states. We first give formulae for deviations in the observables of the MSSM in the decoupling region for the extra two doublet fields. We then examine possible deviations in the Higgs sector numerically, and discuss their phenomenological implications.Comment: 26 pages, 24 figures, text sligtly modified,version to appear in Journal of High Energy Physic

    Data publication with the structural biology data grid supports live analysis

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    Access to experimental X-ray diffraction image data is fundamental for validation and reproduction of macromolecular models and indispensable for development of structural biology processing methods. Here, we established a diffraction data publication and dissemination system, Structural Biology Data Grid (SBDG; data. sbgrid. org), to preserve primary experimental data sets that support scientific publications. Data sets are accessible to researchers through a community driven data grid, which facilitates global data access. Our analysis of a pilot collection of crystallographic data sets demonstrates that the information archived by SBDG is sufficient to reprocess data to statistics that meet or exceed the quality of the original published structures. SBDG has extended its services to the entire community and is used to develop support for other types of biomedical data sets. It is anticipated that access to the experimental data sets will enhance the paradigm shift in the community towards a much more dynamic body of continuously improving data analysis
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