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121.
Three cdg Operons Control Cellular Turnover of Cyclic Di-GMP in Acetobacter xylinum: Genetic Organization and Occurrence of Conserved Domains in Isoenzymes 总被引:5,自引:0,他引:5 下载免费PDF全文
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Systems‐wide analysis of BCR signalosomes and downstream phosphorylation and ubiquitylation 下载免费PDF全文
Petra Beli Rajat Gupta Trine A Kristiansen Dessislava Malinova Chiara Francavilla Pavel Tolar Gail A Bishop Bruce S Hostager Chunaram Choudhary 《Molecular systems biology》2015,11(6)
B‐cell receptor (BCR) signaling is essential for the development and function of B cells; however, the spectrum of proteins involved in BCR signaling is not fully known. Here we used quantitative mass spectrometry‐based proteomics to monitor the dynamics of BCR signaling complexes (signalosomes) and to investigate the dynamics of downstream phosphorylation and ubiquitylation signaling. We identify most of the previously known components of BCR signaling, as well as many proteins that have not yet been implicated in this system. BCR activation leads to rapid tyrosine phosphorylation and ubiquitylation of the receptor‐proximal signaling components, many of which are co‐regulated by both the modifications. We illustrate the power of multilayered proteomic analyses for discovering novel BCR signaling components by demonstrating that BCR‐induced phosphorylation of RAB7A at S72 prevents its association with effector proteins and with endo‐lysosomal compartments. In addition, we show that BCL10 is modified by LUBAC‐mediated linear ubiquitylation, and demonstrate an important function of LUBAC in BCR‐induced NF‐κB signaling. Our results offer a global and integrated view of BCR signaling, and the provided datasets can serve as a valuable resource for further understanding BCR signaling networks. 相似文献
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Rebecca J. Oliver Eleanor Blyth Gail Taylor Jon W. Finch 《Global Change Biology Bioenergy》2015,7(5):958-973
Vegetation exerts large control on global biogeochemical cycles through the processes of photosynthesis and transpiration that exchange CO2 and water between the land and the atmosphere. Increasing atmospheric CO2 concentrations exert direct effects on vegetation through enhanced photosynthesis and reduced stomatal conductance, and indirect effects through changes in climatic variables that drive these processes. How these direct and indirect CO2 impacts interact with each other to affect plant productivity and water use has not been explicitly analysed and remains unclear, yet is important to fully understand the response of the global carbon cycle to future climate change. Here, we use a set of factorial modelling experiments to quantify the direct and indirect impacts of atmospheric CO2 and their interaction on yield and water use in bioenergy short rotation coppice poplar, in addition to quantifying the impact of other environmental drivers such as soil type. We use the JULES land‐surface model forced with a ten‐member ensemble of projected climate change for 2100 with atmospheric CO2 concentrations representative of the A1B emissions scenario. We show that the simulated response of plant productivity to future climate change was nonadditive in JULES, however this nonadditivity was not apparent for plant transpiration. The responses of both growth and transpiration under all experimental scenarios were highly variable between sites, highlighting the complexity of interactions between direct physiological CO2 effects and indirect climate effects. As a result, no general pattern explaining the response of bioenergy poplar water use and yield to future climate change could be discerned across sites. This study suggests attempts to infer future climate change impacts on the land biosphere from studies that force with either the direct or indirect CO2 effects in isolation from each other may lead to incorrect conclusions in terms of both the direction and magnitude of plant response to future climate change. 相似文献
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Beta‐diversity metrics of the upper digestive tract microbiome are associated with body mass index 下载免费PDF全文
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Background
Most diabetic foot amputations are caused by ulcers on the skin of the foot i.e. diabetic foot ulcers. Early identification of patients at high risk for diabetic foot ulcers is crucial. The ‘Simplified 60-Second Diabetic Foot Screening Tool’ has been designed to rapidly detect high risk diabetic feet, allowing for timely identification and referral of patients needing treatment. This study aimed to determine the clinical performance and inter-rater reliability of ‘Simplified 60 Second Diabetic Foot Screening Tool’ in order to evaluate its applicability for routine screening.Methods and Findings
The tool was independently tested by n=12 assessors with n=18 Guyanese patients with diabetes. Inter-rater reliability was assessed by calculating Cronbach’s alpha for each of the assessment items. A minimum value of 0.60 was considered acceptable. Reliability scores of the screening tool assessment items were: ‘monofilament test’ 0.98; ‘active ulcer’ 0.97; ‘previous amputation’ 0.97; ‘previous ulcer’ 0.97; ‘fixed ankle’ 0.91; ‘deformity’ 0.87; ‘callus’ 0.87; ‘absent pulses’ 0.87; ‘fixed toe’ 0.80; ‘blisters’ 0.77; ‘ingrown nail’ 0.72; and ‘fissures’ 0.55. The item ‘stiffness in the toe or ankle’ was removed as it was observed in only 1.3% of patients. The item ‘fissures’ was also removed due to low inter-rater reliability. Clinical performance was assessed via a pilot study utilizing the screening tool on n=1,266 patients in an acute care setting in Georgetown, Guyana. In total, 48% of patients either had existing diabetic foot ulcers or were found to be at high risk for developing ulcers.Conclusions
Clinicians in low and middle income countries such as Guyana can use the Simplified 60-Second Diabetic Screening Tool to facilitate early detection and appropriate treatment of diabetic foot ulcers. Implementation of this screening tool has the potential to decrease diabetes related disability and mortality. 相似文献130.
Samar M. Aoun Gunn Grande Denise Howting Kathleen Deas Chris Toye Lakkhina Troeung Kelli Stajduhar Gail Ewing 《PloS one》2015,10(4)
Family caregiving towards the end-of-life entails considerable emotional, social, financial and physical costs for caregivers. Evidence suggests that good support can improve caregiver psychological outcomes. The primary aim of this study was to investigate the impact of using the carer support needs assessment tool (CSNAT), as an intervention to identify and address support needs in end of life home care, on family caregiver outcomes. A stepped wedge design was used to trial the CSNAT intervention in three bases of Silver Chain Hospice Care in Western Australia, 2012-14. The intervention consisted of at least two visits from nurses (2-3 weeks apart) to identify, review and address caregivers’ needs. The outcome measures for the intervention and control groups were caregiver strain and distress as measured by the Family Appraisal of Caregiving Questionnaire (FACQ-PC), caregiver mental and physical health as measured by SF-12v2, and caregiver workload as measured by extent of caregiver assistance with activities of daily living, at baseline and follow up. Total recruitment was 620. There was 45% attrition for each group between baseline and follow-up mainly due to patient deaths resulting in 322 caregivers completing the study (233 in the intervention group and 89 in the control group). At follow-up, the intervention group showed significant reduction in caregiver strain relative to controls, p=0.018, d=0.348 (95% CI 0.25 to 0.41). Priority support needs identified by caregivers included knowing what to expect in the future, having time for yourself in the day and dealing with your feelings and worries. Despite the challenges at the clinician, organisational and trial levels, the CSNAT intervention led to an improvement in caregiver strain. Effective implementation of an evidence-informed and caregiver-led tool represents a necessary step towards helping palliative care providers better assess and address caregiver needs, ensuring adequate family caregiver support and reduction in caregiver strain. 相似文献