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101.
Nancy Krieger Pamela D. Waterman Anna Kosheleva Jarvis T. Chen Kevin W. Smith Dana R. Carney Gary G. Bennett David R. Williams Gisele Thornhill Elmer R. Freeman 《PloS one》2013,8(10)
Objectives
To date, limited and inconsistent evidence exists regarding racial discrimination and risk of cardiovascular disease (CVD).Methods
Cross-sectional observational study of 1005 US-born non-Hispanic black (n = 504) and white (n = 501) participants age 35–64 randomly selected from community health centers in Boston, MA (2008–2010; 82.4% response rate), using 3 racial discrimination measures: explicit self-report; implicit association test (IAT, a time reaction test for self and group as target vs. perpetrator of discrimination); and structural (Jim Crow status of state of birth, i.e. legal racial discrimination prior 1964).Results
Black and white participants both had adverse cardiovascular and socioeconomic profiles, with black participants most highly exposed to racial discrimination. Positive crude associations among black participants occurred for Jim Crow birthplace and hypertension (odds ratio (OR) 1.92, 95% confidence interval (CI) 1.28, 2.89) and for explicit self-report and the Framingham 10 year CVD risk score (beta = 0.04; 95% CI 0.01, 0.07); among white participants, only negative crude associations existed (for IAT for self, for lower systolic blood pressure (SBP; beta = −4.86; 95% CI −9.08, −0.64) and lower Framingham CVD score (beta = −0.36, 95% CI −0.63, −0.08)). All of these associations were attenuated and all but the white IAT-Framingham risk score association were rendered null in analyses that controlled for lifetime socioeconomic position and additional covariates. Controlling for racial discrimination, socioeconomic position, and other covariates did not attenuate the crude black excess risk for SBP and hypertension and left unaffected the null excess risk for the Framingham CVD score.Conclusion
Despite worse exposures among the black participants, racial discrimination and socioeconomic position were not associated, in multivariable analyses, with risk of CVD. We interpret results in relation to constrained variability of exposures and outcomes and discuss implications for valid research on social determinants of health. 相似文献102.
Martin J. MacInnis Eric A. Carter Michael G. Freeman Bidur Prasad Pandit Ashmita Siwakoti Ankita Subedi Utsav Timalsina Nadia Widmer Ghan Bahadur Thapa Michael S. Koehle Jim L. Rupert 《PloS one》2013,8(10)
Background
Each year, thousands of pilgrims travel to the Janai Purnima festival in Gosainkunda, Nepal (4380 m), ascending rapidly and often without the aid of pharmaceutical prophylaxis.Methods
During the 2012 Janai Purnima festival, 538 subjects were recruited in Dhunche (1950 m) before ascending to Gosainkunda. Through interviews, subjects provided demographic information, ratings of AMS symptoms (Lake Louise Scores; LLS), ascent profiles, and strategies for prophylaxis.Results
In the 491 subjects (91% follow-up rate) who were assessed upon arrival at Gosainkunda, the incidence of AMS was 34.0%. AMS was more common in females than in males (RR = 1.57; 95% CI = 1.23, 2.00), and the AMS incidence was greater in subjects >35 years compared to subjects ≤35 years (RR = 1.63; 95% CI = 1.36, 1.95). There was a greater incidence of AMS in subjects who chose to use garlic as a prophylactic compared to those who did not (RR = 1.69; 95% CI = 1.26, 2.28). Although the LLS of brothers had a moderate correlation (intraclass correlation = 0.40, p = 0.023), sibling AMS status was a weak predictor of AMS.Conclusions
The incidence of AMS upon reaching 4380 m was 34% in a large population of Nepalese pilgrims. Sex, age, and ascent rate were significant factors in the development of AMS, and traditional Nepalese remedies were ineffective in the prevention of AMS. 相似文献103.
Masayasu Naito Ursula Hainz Ute E. Burkhardt Buyin Fu Deborah Ahove Kristen E. Stevenson Mohini Rajasagi Baogong Zhu Anselmo Alonso Elizabeth Witten Ken-ichi Matsuoka Donna Neuberg Jonathan S. Duke-Cohan Catherine J. Wu Gordon J. Freeman 《Cancer immunology, immunotherapy : CII》2013,62(2):347-357
CD40L has a well-established role in enhancing the immunostimulatory capacity of normal and malignant B cells, but a formulation suitable for clinical use has not been widely available. Like other TNF family members, in vivo and in vitro activity of CD40L requires a homotrimeric configuration, and growing evidence suggests that bioactivity depends on higher-order clustering of CD40. We generated a novel formulation of human recombinant CD40L (CD40L-Tri) in which the CD40L extracellular domain and a trimerization motif are connected by a long flexible peptide linker. We demonstrate that CD40L-Tri significantly expands normal CD19+ B cells by over 20- to 30-fold over 14 days and induces B cells to become highly immunostimulatory antigen-presenting cells (APCs). Consistent with these results, CD40L-Tri-activated B cells could effectively stimulate antigen-specific T responses (against the influenza M1 peptide) from normal volunteers. In addition, CD40L-Tri could induce malignant B cells to become effective APCs, such that tumor-directed immune responses could be probed. Together, our studies demonstrate the potent immune-stimulatory effects of CD40L-Tri on B cells that enable their expansion of antigen-specific human T cells. The potent bioactivity of CD40L-Tri is related to its ability to self-multimerize, which may be facilitated by its long peptide linker. 相似文献
104.
Aaron L. Smith Sara M. Freeman Ronald J. Voll Larry J. Young Mark M. Goodman 《Bioorganic & medicinal chemistry letters》2013,23(19):5415-5420
The compound 1-(1-(2-(2-(2-fluoroethoxy)-4-(piperidin-4-yloxy)phenyl)acetyl)piperidin-4-yl)-3,4-dihydroquinolin-2(1H)-one (1) was synthesized and positively evaluated in vitro for high potency and selectivity with human oxytocin receptors. The positron emitting analogue, [F-18]1, was synthesized and investigated in vivo via PET imaging using rat and cynomolgus monkey models. PET imaging studies in female Sprague–Dawley rats suggested [F-18]1 reached the brain and accumulated in various regions of the brain, but washed out too rapidly for adequate quantification and localization. In vivo PET imaging studies in a male cynomolgus monkey suggested [F-18]1 had limited brain penetration while specific uptake of radioactivity significantly accumulated within the vasculature of the cerebral ventricles in areas representative of the choroid plexus. 相似文献
105.
David Freeman Rudy Cedillos Samantha Choyke Zana Lukic Kathleen McGuire Shauna Marvin Andrew M. Burrage Stacey Sudholt Ajay Rana Christopher O'Connor Christopher M. Wiethoff Edward M. Campbell 《PloS one》2013,8(4)
α-synuclein dysregulation is a critical aspect of Parkinson''s disease pathology. Recent studies have observed that α-synuclein aggregates are cytotoxic to cells in culture and that this toxicity can be spread between cells. However, the molecular mechanisms governing this cytotoxicity and spread are poorly characterized. Recent studies of viruses and bacteria, which achieve their cytoplasmic entry by rupturing intracellular vesicles, have utilized the redistribution of galectin proteins as a tool to measure vesicle rupture by these organisms. Using this approach, we demonstrate that α-synuclein aggregates can induce the rupture of lysosomes following their endocytosis in neuronal cell lines. This rupture can be induced by the addition of α-synuclein aggregates directly into cells as well as by cell-to-cell transfer of α-synuclein. We also observe that lysosomal rupture by α-synuclein induces a cathepsin B dependent increase in reactive oxygen species (ROS) in target cells. Finally, we observe that α-synuclein aggregates can induce inflammasome activation in THP-1 cells. Lysosomal rupture is known to induce mitochondrial dysfunction and inflammation, both of which are well established aspects of Parkinson''s disease, thus connecting these aspects of Parkinson''s disease to the propagation of α-synuclein pathology in cells. 相似文献
106.
Background
To date the main treatment approach for neuropathic onset scoliosis has utilised thoracic lumbar sacral orthoses (TLSO) to stabilize the spine and enable stable sitting. Dynamic elastomeric fabric orthoses (DEFOs) may achieve both of these aims if used as an early intervention. Due to a lack of evidence in this area, a retrospective audit of case notes was undertaken to understand current orthotic practice investigating the usage, outcomes and clinical characteristics of treated children with neuropathic onset scoliosis. Clinical notes of 180 children at risk for, or identified with, scoliosis were audited using a search matrix to identify diagnostic group, spinal muscle tone, Gross Motor Functional Classification Scale (GMFCS) level, orthotic treatment modalities, scoliosis specific data, surgical interventions, adaptive technologies used, and outcome measurements reported.Results
Of the 180 notes examined, 85 were male; mean age nine years one month [SD four years seven months]. Spinal muscle tone was reported in 137 cases: 122/137 presented as low tone, 4/137 high tone, 6/137 fluctuating tone and 5/137 typical tone. Scoliosis was confirmed in (77/180) of whom (39/77) used a DEFO. Another (43/180) had a spinal curve developing, of whom (22/43) used a DEFO. The remaining (60/180) had no report of spinal curvature, but used a DEFO as a preventative measure. GMFCS scores were reported for 49 children of whom 14/49 were graded as level 4 and 17/49 level 5. Of the children with scoliosis who had spinal curve shapes reported, 48/60 had a C-shape presentation and 12/60 had an S-shape.Conclusions
The findings confirm previously reported papers in children with neuropathic onset scoliosis in relation to curve shape and GMFCS levels. It provides some evidence of the role DEFOs may have in the management of these children, and highlights the need for further research in this area due to the lack of peer-reviewed publications.107.
Natalie J. Freeman Christopher Young Louise Barrett S. Peter Henzi 《Ethology : formerly Zeitschrift fur Tierpsychologie》2016,122(1):45-52
Unrelated male primates frequently cohabit in bisexual groups and, despite being reproductive competitors, have been shown to cooperate in ways that are associated with reproductive success. Such coalitions between males are common in some taxa, where they can serve two primary functions – status management and improved mating opportunities – that subserve long‐ and short‐term objectives. Here, we use observational data to provide information on male coalitions in vervet monkeys (Chlorocebus pygerythrus), a guenon with a multimale group structure. We recorded a total of 62 coalitions from two troops across a 10‐mo period at Samara Game Reserve, South Africa. We found that males who were more frequently associated spatially and who had groomed one another were more likely to form coalitions and did so against higher‐ranking opponents. This was not linked to any evidence that coalitionary aggression provided either short‐ or long‐term reproductive benefits for the aggressors and coalitions were not restricted to the mating season. There was little evidence that particular individuals were targeted, reciprocation between partners was not observed, and recent immigrant males were not targeted disproportionately. Our data suggest that within‐group coalition formation between vervet males may represent something close to an ancestral state whereby males form ad hoc coalitions opportunistically, joining an ongoing dyadic contest to target an opponent without facing the possible risks of dyadic contest, such as a greater chance of injury. 相似文献
108.
Helf Maximilian J. Freeman Michael F. Piel Jörn 《Journal of industrial microbiology & biotechnology》2019,46(3-4):551-563
Journal of Industrial Microbiology & Biotechnology - Polytheonamides are the most extensively modified ribosomally synthesized and post-translationally modified peptide natural products (RiPPs)... 相似文献
109.
Erica Beaucage-Gauvreau William S. P. Robertson Scott C. E. Brandon Robert Fraser Brian J. C. Freeman Ryan B. Graham 《Computer methods in biomechanics and biomedical engineering》2019,22(5):451-464
There is currently no validated full-body lifting model publicly available on the OpenSim modelling platform to estimate spinal loads during lifting. In this study, the existing full-body-lumbar-spine model was adapted and validated for lifting motions to produce the lifting full-body model. Back muscle activations predicted by the model closely matched the measured erector spinae activation patterns. Model estimates of intradiscal pressures and in vivo measurements were strongly correlated. The same spine loading trends were observed for model estimates and reported vertebral body implant measurements. These results demonstrate the suitability of this model to evaluate changes in lumbar loading during lifting. 相似文献
110.
Marina Jimnez‐Muoz Diana J. Cole Stephen N. Freeman Robert A. Robinson Stephen R. Baillie Eleni Matechou 《Ecology and evolution》2019,9(2):769-779
Bird ring‐recovery data have been widely used to estimate demographic parameters such as survival probabilities since the mid‐20th century. However, while the total number of birds ringed each year is usually known, historical information on age at ringing is often not available. A standard ring‐recovery model, for which information on age at ringing is required, cannot be used when historical data are incomplete. We develop a new model to estimate age‐dependent survival probabilities from such historical data when age at ringing is not recorded; we call this the historical data model. This new model provides an extension to the model of Robinson, 2010, Ibis, 152, 651–795 by estimating the proportion of the ringed birds marked as juveniles as an additional parameter. We conduct a simulation study to examine the performance of the historical data model and compare it with other models including the standard and conditional ring‐recovery models. Simulation studies show that the approach of Robinson, 2010, Ibis, 152, 651–795 can cause bias in parameter estimates. In contrast, the historical data model yields similar parameter estimates to the standard model. Parameter redundancy results show that the newly developed historical data model is comparable to the standard ring‐recovery model, in terms of which parameters can be estimated, and has fewer identifiability issues than the conditional model. We illustrate the new proposed model using Blackbird and Sandwich Tern data. The new historical data model allows us to make full use of historical data and estimate the same parameters as the standard model with incomplete data, and in doing so, detect potential changes in demographic parameters further back in time. 相似文献