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91.
Emily Olfson Howard J. Edenberg John Nurnberger Jr Arpana Agrawal Kathleen K. Bucholz Laura A. Almasy David Chorlian Danielle M. Dick Victor M. Hesselbrock John R. Kramer Samuel Kuperman Bernice Porjesz Marc A. Schuckit Jay A. Tischfield Jen‐Chyong Wang Leah Wetherill Tatiana M. Foroud John Rice Alison Goate Laura J. Bierut 《Alcoholism, clinical and experimental research》2014,38(10):2541-2549
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Timothy W. Farrell MD AGSF Leslie Francis PhD JD Teneille Brown JD Lauren E. Ferrante MD MHS Eric Widera MD Ramona Rhodes MD MPH MSCS AGSF Tony Rosen MD MPH Ula Hwang MD MPH Leah J. Witt MD Niranjan Thothala MD MRCP MBA Shan W. Liu MD SD Caroline A. Vitale MD AGSF Ursula K. Braun MD MPH Caroline Stephens PhD RN GNP-BC Debra Saliba MD MPH AGSF 《Journal of the American Geriatrics Society》2020,68(6):1143-1149
Coronavirus disease 2019 (COVID-19) continues to impact older adults disproportionately with respect to serious consequences ranging from severe illness and hospitalization to increased mortality risk. Concurrently, concerns about potential shortages of healthcare professionals and health supplies to address these issues have focused attention on how these resources are ultimately allocated and used. Some strategies, for example, misguidedly use age as an arbitrary criterion that disfavors older adults in resource allocation decisions. This is a companion article to the American Geriatrics Society (AGS) position statement, “Resource Allocation Strategies and Age-Related Considerations in the COVID-19 Era and Beyond.” It is intended to inform stakeholders including hospitals, health systems, and policymakers about ethical considerations that should be considered when developing strategies for allocation of scarce resources during an emergency involving older adults. This review presents the legal and ethical background for the position statement and discusses these issues that informed the development of the AGS positions: (1) age as a determining factor, (2) age as a tiebreaker, (3) criteria with a differential impact on older adults, (4) individual choices and advance directives, (5) racial/ethnic disparities and resource allocation, and (6) scoring systems and their impact on older adults. It also considers the role of advance directives as expressions of individual preferences in pandemics. J Am Geriatr Soc 68:1143–1149, 2020. 相似文献
94.
S. Leah Etheridge Michelle E. Roh Megan E. Cosgrove Veena Sangkhae Norma E. Fox Junmei Chen José A. López Kenneth Kaushansky Ian S. Hitchcock 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(6):2295-2300
The Janus kinase 2 (JAK2) V617F mutation is the primary pathogenic mutation in patients with Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs). Although thrombohemorrhagic incidents are the most common causes of morbidity and mortality in patients with MPNs, the events causing these clotting abnormalities remain unclear. To identify the cells responsible for the dysfunctional hemostasis, we used transgenic mice expressing JAK2V617F in specific lineages involved in thrombosis and hemostasis. When JAK2V617F was expressed in both hematopoietic and endothelial cells (ECs), the mice developed a significant MPN, characterized by thrombocytosis, neutrophilia, and splenomegaly. However, despite having significantly higher platelet counts than controls, these mice showed severely attenuated thrombosis following injury. Interestingly, platelet activation and aggregation in response to agonists was unaltered by JAK2V617F expression. Subsequent bone marrow transplants revealed the contribution of both endothelial and hematopoietic compartments to the attenuated thrombosis. Furthermore, we identified a potential mechanism for this phenotype through JAK2V617F-regulated inhibition of von Willebrand factor (VWF) function and/or secretion. JAK2V617F+ mice display a condition similar to acquired von Willebrand syndrome, exhibiting significantly less high molecular weight VWF and reduced agglutination to ristocetin. These findings greatly advance our understanding of thrombohemorrhagic events in MPNs and highlight the critical role of ECs in the pathology of hematopoietic malignancies.Myeloproliferative neoplasms (MPNs) are clonal hematopoietic stem cell disorders, characterized by significant increases in one or more myeloid-cell lineages. Mutations in the Janus kinase 2 (JAK2) and MPL genes are common in the majority of Philadelphia chromosome-negative (Ph−) MPNs, which include polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). By far the most frequent mutation in MPNs is JAK2V617F (1–4), which occurs in the highly conserved autoinhibitory JAK homology (JH) 2 domain, causing hyperactive kinase activity and hyperproliferation of myeloid progenitor cells, leading to overproduction of red blood cells (RBCs), platelets, and leukocytes. Although ET and PV have a relatively benign clinical course, patients’ life expectancy can be severely reduced by bleeding or thrombosis, the manifestations of which are significantly more common than other MPN-related complications such as myelofibrosis and acute leukemic transformation (5). The frequency and nature of thrombotic and hemorrhagic events vary greatly depending on disease phenotype and patient history. Data taken from a number of previous studies indicate that the probability of major thrombosis ranges between 8–29% (ET) and 11–39% (PV) whereas the incidence of bleeding at initial presentation is less frequent than thrombosis, ranging between 3–18% (ET) and 3–8% (PV) (6–8).A number of abnormalities that could potentially contribute to this prothrombotic phenotype have been identified in the blood and vascular cells of JAK2V617F+ MPN patients. Much work has focused on defining platelet abnormalities, including increased expression of membrane proteins such as P-selectin and tissue factor (TF), which would prime platelets for activation and increase levels of platelet-activation markers and platelet factor 4 (PF4) in the plasma (9–12). Interestingly, however, aggregation studies show a decreased response to ADP and epinephrine in platelets isolated from patients with ET and PV compared with controls (10). Furthermore, no correlation has been made between severity of thrombocytosis in ET patients and increased risk of thrombosis (6, 13). In contrast, extreme thrombocytosis (platelets >1,500 × 109/L) is thought to contribute to a hemorrhagic phenotype in ET patients, and is commonly attributed to the development of acquired von Willebrand syndrome (AVWS) (11, 12, 14), where the increased platelets bind to highly prothrombotic, ultralarge von Willebrand factor (VWF) multimers, removing them from the plasma (15).Recent studies suggest that leukocytosis is a potential thrombotic risk factor in young PV and ET patients, possibly through the interactions of leukocytes, especially neutrophils, with platelets and endothelial cells (ECs) (16, 17) or the production of prothrombotic molecules such as TF. Increased basal activation of neutrophils has been shown in PV and ET patients, including elevated expression of CD11b and levels of neutrophil proteases in the plasma, both of which are prothrombotic (9, 18, 19). Studies have also shown increased activation of vascular ECs in JAK2V617F+ MPN patients. Increased P- and E-selectin levels in the plasma, coupled with decreased levels of nitric oxide (NO), could conceivably contribute to a prothrombotic phenotype. Furthermore, JAK2V617F+ ECs have recently been reported in a subpopulation of MPN patients, and EC expression was coupled with an increased risk of thrombosis (20, 21). Taken together, previous studies describe physiological abnormalities in a number of cell types in JAK2V617F+ MPN patients, all of which could contribute toward increased thrombosis and/or bleeding. However, these data are often contradictory and fail to definitively explain the mechanism/s responsible for the development of thrombohemorrhagic disease.Here, we used FF1 transgenic mice (22) to express human JAK2V617F in specific lineages to determine which cells are responsible for the thrombohemorrhagic manifestations seen in patients with MPNs. FF1 mice were crossed with Pf4-Cre or Tie2-Cre mice to express JAK2V617F specifically in platelets alone, or in hematopoietic cells and ECs, respectively (23–28). These models have provided us with an unparalleled opportunity to determine the specific role/s of JAK2V617F in pathological thrombosis and hemostasis. 相似文献
95.
Todd B. Kashdan Leah M. Adams Antonina S. Farmer Patty Ferssizidis Patrick E. McKnight John B. Nezlek 《Archives of sexual behavior》2014,43(7):1417-1429
A growing literature attests to deficits in social and romantic life quality in people with elevated social anxiety, but no research to date has explored how intense intimate encounters influence social anxiety symptoms. This study investigated whether the presence and quality of sexual activity on a given day predicted less social anxiety and negative cognitions on a subsequent day. We also explored whether the benefits of sexual activity would be stronger for more socially anxious individuals. Over 21 days, 172 undergraduate students described the presence and quality of sexual activity, social anxiety symptoms, and use of social comparisons on the day in question. Time-lagged analyses determined that being sexually active on one day was related to less social anxiety symptoms and the generation of fewer negative social comparisons the next day. Furthermore, more intense experiences of pleasure and connectedness during sex predicted greater reductions in social anxiety the next day for people high in trait social anxiety, compared to those low in trait social anxiety. These results were similar regardless of whether sex occurred in the context of romantic relationships or on weekdays versus weekends. The results suggest that sexual activity, particularly when pleasurable and intimate, may mitigate some of the social anxiety and negative comparisons frequently experienced by people with high trait social anxiety. 相似文献
96.
Objectives
Popular discourse on abortion in film and television assumes that abortions are under- and misrepresented. Research indicates that such representations influence public perception of abortion care and may play a role in the production of social myths around abortion, with consequences for women’s experience of abortion. To date, abortion plotlines in American film and television have not been systematically tracked and analyzed.Study design
A comprehensive online search was conducted to identify all representations of pregnancy decision making and abortion in American film and television through January 2013. Search results were coded for year, pregnancy decision and mortality outcome.Results
A total of 310 plotlines were identified, with an overall upward trend over time in the number of representations of abortion decision making. Of these plotlines, 173 (55.8%) resulted in abortion, 80 (25.8%) in parenting, 13 (4.2%) in adoption and 21 (6.7%) in pregnancy loss, and 16 (5.1%) were unresolved. A total of 13.5% (n= 42) of stories ended with the death of the woman who considered an abortion, whether or not she obtained one.Conclusions
Abortion-related plotlines occur more frequently than popular discourse assumes. Year-to-year variation in frequency suggests an interactive relationship between media representations, cultural attitudes and policies around abortion regulation, consistent with cultural theory of the relationship between media products and social beliefs. Patterns of outcomes and rates of mortality are not representative of real experience and may contribute to social myths around abortion. The narrative linking of pregnancy termination with mortality is of particular note, supporting the social myth associating abortion with death.Implications
This analysis empirically describes the number of abortion-related plotlines in American film and television. It contributes to the systematic evaluation of the portrayal of abortion in popular culture and provides abortion care professionals and advocates with an initial accurate window into cultural stories being told about abortion. 相似文献97.
98.
Stress and eating disorder behavior in anorexia nervosa as a function of menstrual cycle status 下载免费PDF全文
99.
Compromised health negatively impacts older persons’ ability to participate in expected social roles. Researchers have published little empirical work, however, to explore these issues in HIV endemic African settings. Qualitative interviews with 30 women, aged 60-plus, in rural South Africa, provide insight into the relationship between health and daily activities, with attention to the fulfillment of social roles. In this poor HIV endemic context, older women make connections between their compromised health and their (lack of) capacity to perform the daily tasks that they view as expected of them. By expanding the conceptualization of health to include the capacity to achieve the expectations and perform the tasks expected of one, we better understand how and why health and performance of daily activities are so intricately linked in the minds of respondents. This also provides a starting point for thinking about the social and structural support needed by older persons in these settings, especially as HIV erodes familial supports. 相似文献
100.