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The present article investigates the traumatic brain injury (TBI)-suicide link, assessing whether (a) TBI accounts for variance in suicide risk, and (b) the interpersonal-psychological theory of suicide can be applied to TBI status. Matched case-control procedures applied to archival college student health data identified TBI and non-TBI subsamples (84 total). Individuals with a TBI possessed higher suicide risk than those without. Even accounting for the relative influence of strong suicide risk factors (i.e., depression, perceived burdensomeness, thwarted belongingness, and acquired capability), TBI was robustly associated with suicide risk. TBI history would be valuable to ascertain in assessing suicide risk. 相似文献
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Brennan J. Thompson Eric D. Ryan Eric J. Sobolewski Eric C. Conchola Joel T. Cramer 《Experimental gerontology》2013
The decline in maximal and rapid isometric torque characteristics may compromise functional living abilities in aging adults while loco-motor muscle groups, such as the leg extensors and flexors, may exhibit different torque–time age related decreases. The purpose of the present study was to examine the age-related differences in maximal and rapid torque characteristics of the leg extensor and flexor muscle groups in young, middle-aged, and old men. Sixty-five healthy men were categorized by age as young (n = 25; mean ± SD age = 24.9 ± 3.0 years), middle-aged (n = 22; age = 50.6 ± 4.0 years), and old (n = 18; age = 66.8 ± 4.5 years). Participants performed maximal voluntary contractions (MVCs) of the leg extensors and flexors and an estimated thigh cross sectional area (eThighCSA) assessment. Peak torque (PT), peak rate of torque development (RTDpeak), absolute RTD and the contractile impulse (IMPULSE) were calculated at time intervals of 30, 50, 100 and 200 ms from the torque–time curve. Relative RTD was calculated at 10, 20, 30, 40 and 50% of MVC from the normalized torque–time curves. PT, RTDpeak and later rapid torque variables (RTD100, RTD200, and IMPULSE200) were greater (P ≤ 0.05) in the young and middle-aged when compared to the old men for both muscle groups. Early (RTD30,50; IMPULSE30,50) and late (IMPULSE100) rapid torque variables were greater (P ≤ 0.05) for the young and middle-aged than the old men for the leg extensors but not the leg flexors, except for RTD30, in which there was no difference between young and old. There were no differences for all relative RTD variables between age groups (P > 0.05). eThighCSA was lower in the old compared to the young (P = 0.001) and middle-aged (P = 0.016) men. Maximal and rapid torque characteristics were preserved in middle-aged men but greatly reduced in older men with differential effects at early and late portions of the torque–time curve between the leg extensors and flexors. Significant decreases in absolute maximal and rapid torque production with no change in relative RTD across age groups and lower eThighCSA in old men may suggest that the loss of rapid torque producing capacities observed in older men may be largely a function of mechanisms associated with loss of muscle strength and muscle mass. 相似文献
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Bendamustine and rituximab in combination with lenalidomide in patients with chronic lymphocytic leukemia 下载免费PDF全文
Jasmin Bahlo Sandra Kluth Christina Rhein Paula Cramer Carolin Gross‐Ophoff Petra Langerbeins Anna‐Maria Fink Barbara Eichhorst Karl‐Anton Kreuzer Norbert Fischer Eugen Tausch Stephan Stilgenbauer Sebastian Böttcher Hartmut Döhner Michael Kneba Martin Dreyling Mascha Binder Michael Hallek Clemens‐Martin Wendtner the German CLL Study Group 《European journal of haematology》2016,97(3):253-260
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Tuning the endothelial response: differential release of exocytic cargos from Weibel‐Palade bodies 下载免费PDF全文
T. D. Nightingale J. J. McCormack W. Grimes C. Robinson M. Lopes da Silva I. J. White A. Vaughan L. P. Cramer D. F. Cutler 《Journal of thrombosis and haemostasis》2018,16(9):1873-1886
Essentials
- Endothelial activation initiates multiple processes, including hemostasis and inflammation.
- The molecules that contribute to these processes are co‐stored in secretory granules.
- How can the cells control release of granule content to allow differentiated responses?
- Selected agonists recruit an exocytosis‐linked actin ring to boost release of a subset of cargo.
Summary
Background
Endothelial cells harbor specialized storage organelles, Weibel‐Palade bodies (WPBs). Exocytosis of WPB content into the vascular lumen initiates primary hemostasis, mediated by von Willebrand factor (VWF), and inflammation, mediated by several proteins including P‐selectin. During full fusion, secretion of this large hemostatic protein and smaller pro‐inflammatory proteins are thought to be inextricably linked.Objective
To determine if secretagogue‐dependent differential release of WPB cargo occurs, and whether this is mediated by the formation of an actomyosin ring during exocytosis.Methods
We used VWF string analysis, leukocyte rolling assays, ELISA, spinning disk confocal microscopy, high‐throughput confocal microscopy and inhibitor and siRNA treatments to demonstrate the existence of cellular machinery that allows differential release of WPB cargo proteins.Results
Inhibition of the actomyosin ring differentially effects two processes regulated by WPB exocytosis; it perturbs VWF string formation but has no effect on leukocyte rolling. The efficiency of ring recruitment correlates with VWF release; the ratio of release of VWF to small cargoes decreases when ring recruitment is inhibited. The recruitment of the actin ring is time dependent (fusion events occurring directly after stimulation are less likely to initiate hemostasis than later events) and is activated by protein kinase C (PKC) isoforms.Conclusions
Secretagogues differentially recruit the actomyosin ring, thus demonstrating one mechanism by which the prothrombotic effect of endothelial activation can be modulated. This potentially limits thrombosis whilst permitting a normal inflammatory response. These results have implications for the assessment of WPB fusion, cargo‐content release and the treatment of patients with von Willebrand disease.59.
Margaret Glogowska Rosemary Simmonds Sarah McLachlan Helen Cramer Tom Sanders Rachel Johnson Umesh T. Kadam Daniel S. Lasserson Sarah Purdy 《Annals of family medicine》2015,13(5):466-471
PURPOSE
The purpose of this study was to explore the perceptions and experiences of health care clinicians working in multidisciplinary teams that include specialist heart failure nurses when caring for the management of heart failure patients.METHODS
We used a qualitative in-depth interview study nested in a broader ethnographic study of unplanned admissions in heart failure patients (HoldFAST). We interviewed 24 clinicians across primary, secondary, and community care in 3 locations in the Midlands, South Central, and South West of England.RESULTS
Within a framework of the role and contribution of the heart failure specialist nurse, our study identified 2 thematic areas that the clinicians agreed still represent particular challenges when working with heart failure patients. The first was communication with patients, in particular explaining the diagnosis and helping patients to understand the condition. The participants recognized that such communication was most effective when they had a long-term relationship with patients and families and that the specialist nurse played an important part in achieving this relationship. The second was communication within the team. Multidisciplinary input was especially needed because of the complexity of many patients and issues around medications, and the participants believed the specialist nurse may facilitate team communication.CONCLUSIONS
The study highlights the role of specialist heart failure nurses in delivering education tailored to patients and facilitating better liaison among all clinicians, particularly when dealing with the management of comorbidities and drug regimens. The way in which specialist nurses were able to be caseworkers for their patients was perceived as a method of ensuring coordination and continuity of care. 相似文献60.
The hypothesis that 17 beta-estradiol suppresses dopamine secretion into hypophysial portal blood was tested. Portal plasma concentrations of dopamine were significantly lower in proestrous rats (1.0 +/- 0.1 ng/ml; mean +/- SE) than in estrous rats (1.9 +/- 0.38 ng/ml). To deplete the animal of endogenous steroid hormones, proestrous rats were adrenalectomized (Adx) and ovariectomized (Ovx). Twenty-four hours later, hypophysial portal blood was collected for 60 min, and the plasma from this blood was analyzed for dopamine. Arterial plasma from these rats was assayed for 17 beta-estradiol and progesterone. The concentrations of dopamine in the portal plasma of sham-operated rats and bilaterally Adx-Ovx rats were similar to those in estrous animals. The concentration of dopamine in portal plasma of Adx-Ovs rats injected 24 h earlier with 50 micrograms 17 beta-estradiol was 1.0 +/- 0.31 ng/ml, which was comparable to that in proestrous animals but less than that in the estrous rats. The concentrations of 17 beta-estradiol in arterial plasma were as follows: 24 +/- 8.3 pg/ml in proestrous rats, 40 +/- 2.9 pg/ml in estrous rats, 10 +/- 1.3 pg/ml in Adx-ovx rats, and 96 +/- 17.3 pg/ml in Adx-Ovx rats injected with 50 micrograms 17 beta-estradiol. Twenty-four hours after injection of 25 micrograms 17beta-extradiol into Adx-Ovx rats, the plasma 17beta-estradiol levels were 51 +/- 7.4 pg/ml, and the dopamine concentrations in portal plasma were 1.9 +/- 0.57 ng/ml. It is concluded that an acute effect of 17 beta-estradiol is suppression of hypothalamic secretion of dopamine into hypophysial portal blood. 相似文献