143 research outputs found
Stress, enrichment and the welfare of domestic cats in rescue shelters
EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Regulation of neovascularization by S-glutathionylation via the Wnt5a/sFlt-1 pathway
S-glutathionylation occurs when reactive oxygen or nitrogen species react with protein-cysteine thiols. Glutaredoxin-1 (Glrx) is a cytosolic enzyme which enzymatically catalyses the reduction in S-glutathionylation, conferring reversible signalling function to proteins with redox-sensitive thiols. Glrx can regulate vascular hypertrophy and inflammation by regulating the activity of nuclear factor ĪŗB (NF-ĪŗB) and actin polymerization. Vascular endothelial growth factor (VEGF)-induced endothelial cell (EC) migration is inhibited by Glrx overexpression. In mice overexpressing Glrx, blood flow recovery, exercise function and capillary density were significantly attenuated after hindlimb ischaemia (HLI). Wnt5a and soluble Fms-like tyrosine kinase-1 (sFlt-1) were enhanced in the ischaemic-limb muscle and plasma respectively from Glrx transgenic (TG) mice. A Wnt5a/sFlt-1 pathway had been described in myeloid cells controlling retinal blood vessel development. Interestingly, a Wnt5a/sFlt-1 pathway was found also to play a role in EC to inhibit network formation. S-glutathionylation of NF-ĪŗB components inhibits its activation. Up-regulated Glrx stimulated the Wnt5a/sFlt-1 pathway through enhancing NF-ĪŗB signalling. These studies show a novel role for Glrx in post-ischaemic neovascularization, which could define a potential target for therapy of impaired angiogenesis in pathological conditions including diabetes
Gene expression in Citrus sinensis fruit tissues harvested from huanglongbing-infected trees: comparison with girdled fruit
Distribution of viable Candidatus Liberibacter asiaticus (CaLas) in sweet orange fruit and leaves (āHamlinā and āValenciaā) and transcriptomic changes associated with huanglongbing (HLB) infection in fruit tissues are reported. Viable CaLas was present in most fruit tissues tested in HLB trees, with the highest titre detected in vascular tissue near the calyx abscission zone. Transcriptomic changes associated with HLB infection were analysed in flavedo (FF), vascular tissue (VT), and juice vesicles (JV) from symptomatic (SY), asymptomatic (AS), and healthy (H) fruit. In SY āHamlinā, HLB altered the expression of more genes in FF and VT than in JV, whereas in SY āValenciaā, the number of genes whose expression was changed by HLB was similar in these tissues. The expression of more genes was altered in SY āValenciaā JV than in SY āHamlinā JV. More genes were also affected in AS āValenciaā FF and VT than in AS āValenciaā JV. Most genes whose expression was changed by HLB were classified as transporters or involved in carbohydrate metabolism. Physiological characteristics of HLB-infected and girdled fruit were compared to differentiate between HLB-specific and carbohydrate metabolism-related symptoms. SY and girdled fruit were smaller than H and ungirdled fruit, respectively, with poor juice quality. However, girdling did not cause misshapen fruit or differential peel coloration. Quantitative PCR analysis indicated that many selected genes changed their expression significantly in SY flavedo but not in girdled flavedo. Mechanisms regulating development of HLB symptoms may lie in the host disease response rather than being a direct consequence of carbohydrate starvation
Compendium of Single Event Effects Results for Candidate Spacecraft Electronics for NASA
Susceptibility of a variety of candidate spacecraft electronics to proton and heavy ion induced single event effects is studied. Devices tested include digital, linear bipolar, and hybrid devices
The Business Case for Preconception Care: Methods and Issues
Only a limited number of economic evaluations have addressed the costs and benefits of preconception care. In order to persuade health care providers, payers, or purchasers to become actively involved in promoting preconception care, it is important to demonstrate the value of doing so through development of a ābusiness caseā. Perceived benefits in terms of organizational reputation and market share can be influential in forming a business case. In addition, it is standard to include an economic analysis of financial costs and benefits from the perspective of the provider practice, payer, or purchaser in a business case. The methods, data needs, and other issues involved with preparing an economic analysis of the likely financial return on investment in preconception care are presented here. This is accompanied by a review or case study of economic evaluations of preconception care for women with recognized diabetes. Although the data are not sufficient to draw firm conclusions, there are indications that such care may yield positive financial benefits to health care organizations through reduction in maternal and infant hospitalizations. More work is needed to establish how costs and economic benefits are distributed among different types of organizations. Also, the optimum methods of delivering preconception care for women with diabetes need to be evaluated. Similar assessments should also be conducted for other forms of preconception care, including comprehensive care
WNT activation by lithium abrogates TP53 mutation associated radiation resistance in medulloblastoma
TP53 mutations confer subgroup specific poor survival for children with medulloblastoma. We hypothesized that WNT activation which is associated with improved survival for such children abrogates TP53 related radioresistance and can be used to sensitize TP53 mutant tumors for radiation. We examined the subgroup-specific role of TP53 mutations in a cohort of 314 patients treated with radiation. TP53 wild-type or mutant human medulloblastoma cell-lines and normal neural stem cells were used to test radioresistance of TP53 mutations and the radiosensitizing effect of WNT activation on tumors and the developing brain. Children with WNT/TP53 mutant medulloblastoma had higher 5-year survival than those with SHH/TP53 mutant tumours (100% and 36.6% +/- 8.7%, respectively (p < 0.001)). Introduction of TP53 mutation into medulloblastoma cells induced radioresistance (survival fractions at 2Gy (SF2) of 89% +/- 2% vs. 57.4% +/- 1.8% (p < 0.01)). In contrast, beta-catenin mutation sensitized TP53 mutant cells to radiation (p < 0.05). Lithium, an activator of the WNT pathway, sensitized TP53 mutant medulloblastoma to radiation (SF2 of 43.5% +/- 1.5% in lithium treated cells vs. 56.6 +/- 3% (p < 0.01)) accompanied by increased number of.H2AX foci. Normal neural stem cells were protected from lithium induced radiation damage (SF2 of 33% +/- 8% for lithium treated cells vs. 27% +/- 3% for untreated controls (p = 0.05). Poor survival of patients with TP53 mutant medulloblastoma may be related to radiation resistance. Since constitutive activation of the WNT pathway by lithium sensitizes TP53 mutant medulloblastoma cells and protect normal neural stem cells from radiation, this oral drug may represent an attractive novel therapy for high-risk medulloblastomas.B.R.A.I.N Child Canada; Cancer Research UK; Brain Tumour Charity; Hungarian Brain Research Program [KTIA_13_NAP-A-V/3]; Janos Bolyai Scholarship of the Hungarian Academy of Sciences [TAMOP-4.2.2. A-11/1/KONV-2012-0025]; German Cancer Aid/Dr. Mildred Scheel Foundation for Cancer Research; Cure Childhood Cancer Foundation; St. Baldrick's Foundation; Southeastern Brain Tumor Foundation; Action Medical Research; [CZ.1.05/2.1.00/03.0101]; [CZ.1.07/2.3.00/20.0183
Sequence-non-specific effects of RNA interference triggers and microRNA regulators
RNA reagents of diverse lengths and structures, unmodified or containing various chemical modifications are powerful tools of RNA interference and microRNA technologies. These reagents which are either delivered to cells using appropriate carriers or are expressed in cells from suitable vectors often cause unintended sequence-non-specific immune responses besides triggering intended sequence-specific silencing effects. This article reviews the present state of knowledge regarding the cellular sensors of foreign RNA, the signaling pathways these sensors mobilize and shows which specific features of the RNA reagents set the responsive systems on alert. The representative examples of toxic effects caused in the investigated cell lines and tissues by the RNAs of specific types and structures are collected and may be instructive for further studies of sequence-non-specific responses to foreign RNA in human cells
Progress and prospects for event tourism research
This paper examines event tourism as a field of study and area of professional practice updating the previous review article published in 2008. In this substantially extended review, a deeper analysis of the fieldās evolution and development is presented, charting the growth of the literature, focusing both chronologically and thematically. A framework for understanding and creating knowledge about events and tourism is presented, forming the basis which signposts established research themes and concepts and outlines future directions for research. In addition, the review article focuses on constraining and propelling forces, ontological advances, contributions from key journals, and emerging themes and issues. It also presents a roadmap for research activity in event tourism
Clinical development of new drug-radiotherapy combinations.
In countries with the best cancer outcomes, approximately 60% of patients receive radiotherapy as part of their treatment, which is one of the most cost-effective cancer treatments. Notably, around 40% of cancer cures include the use of radiotherapy, either as a single modality or combined with other treatments. Radiotherapy can provide enormous benefit to patients with cancer. In the past decade, significant technical advances, such as image-guided radiotherapy, intensity-modulated radiotherapy, stereotactic radiotherapy, and proton therapy enable higher doses of radiotherapy to be delivered to the tumour with significantly lower doses to normal surrounding tissues. However, apart from the combination of traditional cytotoxic chemotherapy with radiotherapy, little progress has been made in identifying and defining optimal targeted therapy and radiotherapy combinations to improve the efficacy of cancer treatment. The National Cancer Research Institute Clinical and Translational Radiotherapy Research Working Group (CTRad) formed a Joint Working Group with representatives from academia, industry, patient groups and regulatory bodies to address this lack of progress and to publish recommendations for future clinical research. Herein, we highlight the Working Group's consensus recommendations to increase the number of novel drugs being successfully registered in combination with radiotherapy to improve clinical outcomes for patients with cancer.National Institute for Health ResearchThis is the final version of the article. It first appeared from Nature Publishing Group via http://dx.doi.org/10.1038/nrclinonc.2016.7
Act now against new NHS competition regulations: an open letter to the BMA and the Academy of Medical Royal Colleges calls on them to make a joint public statement of opposition to the amended section 75 regulations.
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