1,010 research outputs found

    Elastic interactions of active cells with soft materials

    Full text link
    Anchorage-dependent cells collect information on the mechanical properties of the environment through their contractile machineries and use this information to position and orient themselves. Since the probing process is anisotropic, cellular force patterns during active mechanosensing can be modelled as anisotropic force contraction dipoles. Their build-up depends on the mechanical properties of the environment, including elastic rigidity and prestrain. In a finite sized sample, it also depends on sample geometry and boundary conditions through image strain fields. We discuss the interactions of active cells with an elastic environment and compare it to the case of physical force dipoles. Despite marked differences, both cases can be described in the same theoretical framework. We exactly solve the elastic equations for anisotropic force contraction dipoles in different geometries (full space, halfspace and sphere) and with different boundary conditions. These results are then used to predict optimal position and orientation of mechanosensing cells in soft material.Comment: Revtex, 38 pages, 8 Postscript files included; revised version, accepted for publication in Phys. Rev.

    Characteristics of patients initiating raloxifene compared to those initiating bisphosphonates

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Both raloxifene and bisphosphonates are indicated for the prevention and treatment of postmenopausal osteoporosis, however these medications have different efficacy and safety profiles. It is plausible that physicians would prescribe these agents to optimize the benefit/risk profile for individual patients. The objective of this study was to compare demographic and clinical characteristics of patients initiating raloxifene with those of patients initiating bisphosphonates for the prevention and treatment of osteoporosis.</p> <p>Methods</p> <p>This study was conducted using a retrospective cohort design. Female beneficiaries (45 years and older) with at least one claim for raloxifene or a bisphosphonate in 2003 through 2005 and continuous enrollment in the previous 12 months and subsequent 6 months were identified using a collection of large national commercial, Medicare supplemental, and Medicaid administrative claims databases (MarketScan<sup>®</sup>). Patients were divided into two cohorts, a combined commercial/Medicare cohort and a Medicaid cohort. Within each cohort, characteristics (demographic, clinical, and resource utilization) of patients initiating raloxifene were compared to those of patients initiating bisphosphonate therapy. Group comparisons were made using chi-square tests for proportions of categorical measures and Wilcoxon rank-sum tests for continuous variables. Logistic regression was used to simultaneously examine factors independently associated with initiation of raloxifene versus a bisphosphonate.</p> <p>Results</p> <p>Within both the commercial/Medicare and Medicaid cohorts, raloxifene patients were younger, had fewer comorbid conditions, and fewer pre-existing fractures than bisphosphonate patients. Raloxifene patients in both cohorts were less likely to have had a bone mineral density (BMD) screening in the previous year than were bisphosphonate patients, and were also more likely to have used estrogen or estrogen/progestin therapy in the previous 12 months. These differences remained statistically significant in the multivariate model.</p> <p>Conclusion</p> <p>In this sample of patients enrolled in commercial, Medicare, and Medicaid plans, patients who initiated raloxifene treatment differed from those initiating bisphosphonates. Raloxifene patients were younger, had better overall health status and appeared to be less likely to have risk factors for new osteoporotic fractures than bisphosphonate patients. Differences in the clinical profiles of these agents may impact prescribing decisions. Investigators using observational data to make comparisons of treatment outcomes associated with these medications should take these important differences in patient characteristics into consideration.</p

    Divergent consensuses on Arctic amplification influence on midlatitude severe winter weather

    Get PDF
    The article of record as published may be found at https://doi.org/10.1038/s41558-019-0662-yWe thank R. Blackport, C. Deser, L. Sun, J. Screen and D. Smith for discussions and suggested revisions to the manuscript. We also thank J. Screen and L. Sun for model data. A. Amin helped to create Fig. 2. US CLIVAR logistically and financially supported the Arctic-Midlatitude Working Group and Arctic Change and its Influence on Mid-Latitude Climate and Weather workshop that resulted in this article. J.C. is supported by the US National Science Foundation grants AGS-1657748 and PLR-1504361, 1901352. M.W. acknowledges funding by the Deutsche Forschungsgemeinschaft project no. 268020496– TRR 172, within the Transregional Collaborative Research Center “Arctic Amplification: Climate Relevant Atmospheric and Surface Processes, and Feedback Mechanisms (AC)3 ”. T.V. was supported by the Academy of Finland grant 317999. J.O. was supported by the NOAA Arctic Research Program. J.F. was supported by the Woods Hole Research Center. S.W. and H.G. are supported by the US DOE Award Number DE-SC0016605. J.Y. was supported by the Korea Meteorological Administration Research and Development Program under grant KMI2018-01015 and National Research Foundation grant NRF_2017R1A2B4007480. D.H. is supported by the Helmholtz Association of German Research Centers (grant FKZ HRSF-0036, project POLEX). The authors acknowledge the World Climate Research Programme’s Working Group on Coupled Modelling, which is responsible for CMIP, and thank the climate modelling groups (listed in Supplementary Table 1) for producing and making available their model output. For CMIP, the US Department of Energy’s PCMDI provides coordinating support and led development of software infrastructure in partnership with the Global Organization for Earth System Science Portals.The Arctic has warmed more than twice as fast as the global average since the late twentieth century, a phenomenon known as Arctic amplification (AA). Recently, there have been considerable advances in understanding the physical contributions to AA, and progress has been made in understanding the mechanisms that link it to midlatitude weather variability. Observational studies overwhelmingly support that AA is contributing to winter continental cooling. Although some model experiments sup port the observational evidence, most modelling results show little connection between AA and severe midlatitude weather or suggest the export of excess heating from the Arctic to lower latitudes. Divergent conclusions between model and observational studies, and even intramodel studies, continue to obfuscate a clear understanding of how AA is influencing midlatitude weather

    Risk of urinary bladder cancer: a case-control analysis of industry and occupation

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Uncertainty remains about urinary bladder cancer (UBC) risk for many occupations. Here, we investigate the association between occupation, industry and UBC.</p> <p>Methods</p> <p>Lifetime occupational history was collected by in-person interview for 604 newly diagnosed UBC patients and 604 cancer-free controls. Each job title was assigned a two-digit industry code and a three-digit occupation code. Odds ratios (ORs) for UBC associated with ever being employed in an industry or occupation were calculated by unconditional logistic regression adjusting for age, gender and smoking status. We also examined UBC risk by duration of employment (>0 to <10, ≥10 years) in industry or occupation.</p> <p>Results</p> <p>Significantly increased risk of UBC was observed among waiters and bartenders (OR 2.87; 95% CI 1.05 to 7.72) and occupations related to medicine and health (OR 2.17; 95% CI 1.21 to 3.92), agricultural production, livestock and animal specialties (OR 1.90; 95% CI 1.03 to 3.49), electrical assembly, installation and repair (OR 1.69; 95% CI 1.07 to 2.65), communications (OR 1.74; 95% CI 1.00 to 3.01), and health services (OR 1.58; 95% CI 1.02 to 2.44). For these occupations we also observed a significant excess risk of UBC for long-term work (i.e. ≥10 years), with the exception of waiters and bartenders. Employment for 10 years or more was associated with increased risk of UBC in general farmers (OR 9.58; 95% CI 2.18 to 42.05), agricultural production of crops (OR 3.36; 95% CI 1.10 to 10.27), occupations related to bench working (OR 4.76; 95% CI 1.74 to 13.01), agricultural, fishery, forestry & related (OR 4.58; 95% CI 1.97 to 10.65), transportation equipment (OR 2.68; 95% CI 1.03 to 6.97), and structural work (OR 1.85; 95% CI 1.16 to 2.95).</p> <p>Conclusions</p> <p>This study provides evidence of increased risk of UBC for occupations that were previously reported as at-risk. Workers in several occupation and industry groups have a significantly higher risk of UBC, particularly when duration of employment is 10 years or more.</p

    Development of a Patient-Report Measure of Psychotherapy for Depression

    Get PDF
    Despite clear indications of need to improve depression treatment, practical tools that efficiently measure psychotherapy are not available. We developed a patient-report measure of psychotherapy for depression that assesses Cognitive Behavioral (CBT), Interpersonal (IPT), and Psychodynamic therapies. 420 patients with depression from a large managed behavioral health care organization completed the measure. The three subscales measuring CBT, IPT, and Psychodynamic Therapy showed good internal consistency, appropriate item-total correlations, and were supported by a 3-factor structure. Our results suggest that a patient questionnaire is a promising approach for assessing psychotherapy in quality improvement interventions

    Physician attitude toward depression care interventions: Implications for implementation of quality improvement initiatives

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Few individuals with depression treated in the primary care setting receive care consistent with clinical treatment guidelines. Interventions based on the chronic care model (CCM) have been promoted to address barriers and improve the quality of care. A current understanding of barriers to depression care and an awareness of whether physicians believe interventions effectively address those barriers is needed to enhance the success of future implementation.</p> <p>Methods</p> <p>We conducted semi-structured interviews with 23 primary care physicians across the US regarding their experience treating patients with depression, barriers to care, and commonly promoted CCM-based interventions. Themes were identified from interview transcripts using a grounded theory approach.</p> <p>Results</p> <p>Six barriers emerged from the interviews: difficulty diagnosing depression, patient resistance, fragmented mental health system, insurance coverage, lack of expertise, and competing demands and other responsibilities as a primary care provider. A number of interventions were seen as helpful in addressing these barriers – including care managers, mental health integration, and education – while others received mixed reviews. Mental health consultation models received the least endorsement. Two systems-related barriers, the fragmented mental health system and insurance coverage limitations, appeared incompletely addressed by the interventions.</p> <p>Conclusion</p> <p>CCM-based interventions, which include care managers, mental health integration, and patient education, are most likely to be implemented successfully because they effectively address several important barriers to care and are endorsed by physicians. Practices considering the adoption of interventions that received less support should educate physicians about the benefit of the interventions and attend to physician concerns prior to implementation. A focus on interventions that address systems-related barriers is needed to overcome all barriers to care.</p

    Walkability and self-rated health in primary care patients

    Get PDF
    BACKGROUND: The objective of this study was to investigate the relationship between perceived walkability and overall self-rated health among patients who use community-based clinics. METHODS: A cross-sectional survey was distributed to a convenience sample in three community clinics. Forms were completed by 793 clinic patients. Multiple logistic regression analysis was to control for the effects of demographic variables and lifestyles. RESULTS: Perceiving the availability of places to walk was related to better self-rated health. The most important places were work (OR = 3.2), community center (OR = 3.12), park (OR = 2.45) and day care (OR = 2.05). Respondents who said they had zero (OR = .27) or one (OR = .49) place to walk were significantly less healthy than persons who said they had five or more places to walk. CONCLUSION: Persons who perceived that they had no place to walk were significantly less healthy than persons who thought they had at least one place to walk (OR = .39). Support for walkable neighborhoods and education of patients about options for walking may be in the best interests of community medicine patients
    corecore