107 research outputs found
Quality of life in children with acute lymphoblastic leukaemia: A systematic review
Quality of life (QOL) in children with acute lymphoblastic leukaemia (ALL) is now considered an important outcome measure of treatment for this disease. The aim of this paper is to systematically review studies on QOL in children during treatment for ALL with consideration to methodological details and quality of studies, empirical findings on QOL as reported by children and parents, and whether children and parents differ in their reports on QOL. Searches were conducted in biomedical, psychological and behavioural science databases. Six papers met inclusion criteria for review: 4 cross-sectional studies and 2 qualitative studies. There was little consistency in how QOL was measured or qualitatively assessed across studies. The quality of most studies was limited by small sample sizes and cross-sectional designs. Children's reports on QOL were represented in 3 studies and discrepancies were found between children's and parent's accounts of QOL. There is a need for ongoing research on QOL in children with ALL that use longitudinal designs, large sample sizes, and child reports of QOL. There is a need for theoretical development of the concept of QOL through concept analysis, grounded theory research and empirical validation of developing theory of QOL. Theoretical development of the concept of QOL will contribute to greater clarification of what is meant by QOL than currently exists which in turn has the potential to advance the methodology of measuring this concept in children
A near death experience: Shigella manipulates host death machinery to silence innate immunity
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108703/1/embj201489680.pd
Homeostatic maintenance of pathogen-containing vacuoles requires TBK1-dependent regulation of aquaporin-1
Membranes are an integral component of many cellular functions and serve as a barrier to keep pathogenic bacteria from entering the nutrient-rich host cytosol. TANK-binding-kinase-1 (TBK1), a kinase of the IÎșB kinase family, is required for maintaining integrity of pathogen-containing vacuoles (PCV) upon bacterial invasion of host cells. Here we investigate how vacuolar integrity is maintained during bacterial infection, even in the presence of bacterial membrane damaging agents. We found that Aquaporin-1 (AQP1), a water channel that regulates swelling of secretory vesicles, associated with PCV. AQP1 levels were elevated in TBK1-deficient cells, and overexpression of AQP1 in wild-type cells led to PCV destabilization, similar to that observed in tbk1 â/ â cells. Inhibition of physiological levels of AQP1 in multiple cell types also led to increased instability of PCV, demonstrating a need for tightly regulated AQP1 function to maintain vacuole homeostasis during bacterial infection. AQP1-dependent modulation of PCV was triggered by bacterially induced membrane damage and ion flux. These results highlight the contribution of water channels to promoting PCV membrane integrity, and reveal an unexpected role for TBK1 and AQP1 in restricting bacterial pathogens to the vacuolar compartment.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72109/1/j.1462-5822.2008.01199.x.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/72109/2/CMI_1199_sm_Figs_S1-S3_and_Table_S1.pd
Caspase-2 mediates a Brucella abortus RB51-induced hybrid cell death having features of apoptosis and pyroptosis
Programmed cell death (PCD) can play a crucial role in tuning the immune response to microbial infection. Although PCD can occur in different forms, all are mediated by a family of proteases called caspases. Caspase-2 is the most conserved caspase, however, its function in cell death is ill-defined. Previously we demonstrated that live attenuated cattle vaccine strain Brucella abortus RB51 induces caspase-2-mediated and caspase-1-independent PCD of infected macrophages. We also discovered that rough attenuated B. suis strain VTRS1 induces a caspase-2-mediated and caspase-1-independent proinflammatory cell death in infected macrophages, which was tentatively coined âcaspase-2-mediated pyroptosisâ. However, the mechanism of caspase-2-mediated cell death pathway remained unclear. In this study, we found that caspase-2 mediated proinflammatory cell death of RB51-infected macrophages and regulated many genes in different PCD pathways. We show that the activation of proapoptotic caspases-3 and -8 was dependent upon caspase-2. Caspase-2 regulated mitochondrial cytochrome c release and TNFα production, both of which are known to activate caspase-3 and caspase-8, respectively. In addition to TNFα, RB51-induced caspase-1 and IL-1ÎČ production was also driven by caspase-2-mediated mitochondrial dysfunction. Interestingly, pore formation, a phenomenon commonly associated with caspase-1-mediated pyroptosis, occurred; however, unlike its role in S. typhimurium-induced pyroptosis, pore formation did not contribute to RB51-induced proinflammatory cell death. Our data suggest that caspase-2 acts as an initiator caspase that mediates a novel RB51-induced hybrid cell death that simulates but differs from typical non-proinflammatory apoptosis and caspase-1-mediated proinflammatory pyroptosis. The initiator role of the caspase-2-mediated cell death was also conserved in cellular stress-induced cell death of macrophages treated with etoposide, naphthalene, or anti-Fas. Caspase-2 also regulated caspase-3 and -8 activation, as well as cell death in macrophages treated with each of the three reagents. Taken together, our data has demonstrated that caspase-2 can play an important role in mediating a proinflammatory response and a hybrid cell death that demonstrates features of both apoptosis and pyroptosis
Autonomic Testing in Functional Gastrointestinal Disorders: Implications of Reproducible Gastrointestinal Complaints during Tilt Table Testing
Background: The pathophysiology of functional abdominal pain (FAP) is unknown. The upright portion of a tilt table test triggers typical symptoms in certain children.
Aim: To compare the pathophysiology and treatment response of children with FAP whose gastrointestinal symptoms (GI) were replicated (RGI) by tilt table testing (TTT) to those in whom TTT did not have this effect (NRGI).
Methods: An IRB-approved retrospective review of the autonomic laboratory database identified all children tested for GI complaints. We compared results of TTT, Valsalva maneuver, deep breathing and the axon reflex sweat test. Overall treatment response and that specific to fludrocortisone was ranked from 1 to 5, with 1 âmuch worse,â 3 âneutral,â and 5 âmuch better.â
Results: 32/76 identified children had reproducible symptoms on TTT (RGI) and 44 did not (NRGI). The RGI group was younger, had a shorter duration of symptoms, more postural tachycardia syndrome (POTS) and benefited more from fludrocortisone (73% in RGI vs. 25% in NRGI).
Conclusion: Dividing patients with FAP according to the effect of TTT on their symptoms appears to delineate 2 fundamentally different groups, with potentially different pathophysiologies and treatment responses. A prospective study is needed
Inhibitor of Apoptosis Proteins in Eukaryotic Evolution and Development: A Model of Thematic Conservation
The past decade and a half has witnessed the discovery of a large, evolutionarily conserved family of cellular genes bearing homology to the prototype baculovirus Inhibitor of Apoptosis (IAP). The logical decision in the field to also refer to these cellular proteins as IAPs fails to do justice to this versatile group of factors that play a wide range of roles in eukaryotic development and homeostasis which include, but are not limited to, the regulation of programmed cell death. Here we describe the shared functional characteristics of several well-characterized IAPs whose defining motifs place them more in the category of multifunctional modular protein interaction domains
Mice Lacking the Type I Interferon Receptor Are Resistant to Listeria monocytogenes
Listeria monocytogenes is a facultative intracellular pathogen that induces a cytosolic signaling cascade resulting in expression of interferon (IFN)-ÎČ. Although type I IFNs are critical in viral defense, their role in immunity to bacterial pathogens is much less clear. In this study, we addressed the role of type I IFNs by examining the infection of L. monocytogenes in BALB/c mice lacking the type I IFN receptor (IFN-α/ÎČRâ/â). During the first 24 h of infection in vivo, IFN-α/ÎČRâ/â and wild-type mice were similar in terms of L. monocytogenes survival. In addition, the intracellular fate of L. monocytogenes in macrophages cultured from IFN-α/ÎČRâ/â and wild-type mice was indistinguishable. However, by 72 h after inoculation in vivo, IFN-α/ÎČRâ/â mice were âŒ1,000-fold more resistant to a high dose L. monocytogenes infection. Resistance was correlated with elevated levels of interleukin 12p70 in the blood and increased numbers of CD11b+ macrophages producing tumor necrosis factor α in the spleen of IFN-α/ÎČRâ/â mice. The results of this study suggest that L. monocytogenes might be exploiting an innate antiviral response to promote its pathogenesis
Enantioselective isothiourea-catalysed trans-dihydropyridinone synthesis using saccharin-derived ketimines : scope and limitations
The authors thank Syngenta and the EPSRC (grant code EP/K503162/1) (DGS) for funding. The European Research Council under the European Unionâs Seventh Framework Programme (FP7/2007-2013) ERC Grant Agreement No. 279850 is also acknowledged (CMY). ADS thanks the Royal Society for a Wolfson Research Merit Award. We also thank the EPSRC UK National Mass Spectrometry Facility at Swansea University.The catalytic enantioselective synthesis of a range of trans-dihydropyridinones from aryl-, heteroaryl- and alkenylacetic acids and saccharin-derived ketimines with good to excellent stereocontrol (15 examples, up to >95:5 dr, up to >99:1 er) is reported. After extensive optimisation, HyperBTM proved the optimal isothiourea catalyst for this transformation at â78 °C, giving trans-dihydropyridones with generally excellent levels of diastereo- and enantioselectivity.Publisher PDFPeer reviewe
Brucella abortus Infection of Placental Trophoblasts Triggers Endoplasmic Reticulum Stress-Mediated Cell Death and Fetal Loss via Type IV Secretion System-Dependent Activation of CHOP.
Subversion of endoplasmic reticulum (ER) function is a feature shared by multiple intracellular bacteria and viruses, and in many cases this disruption of cellular function activates pathways of the unfolded protein response (UPR). In the case of infection with Brucella abortus, the etiologic agent of brucellosis, the unfolded protein response in the infected placenta contributes to placentitis and abortion, leading to pathogen transmission. Here we show that B. abortus infection of pregnant mice led to death of infected placental trophoblasts in a manner that depended on the VirB type IV secretion system (T4SS) and its effector VceC. The trophoblast death program required the ER stress-induced transcription factor CHOP. While NOD1/NOD2 expression in macrophages contributed to ER stress-induced inflammation, these receptors did not play a role in trophoblast death. Both placentitis and abortion were independent of apoptosis-associated Speck-like protein containing a caspase activation and recruitment domain (ASC). These studies show that B. abortus uses its T4SS to induce cell-type-specific responses to ER stress in trophoblasts that trigger placental inflammation and abortion. Our results suggest further that in B. abortus the T4SS and its effectors are under selection as bacterial transmission factors.IMPORTANCE Brucella abortus infects the placenta of pregnant cows, where it replicates to high levels and triggers abortion of the calf. The aborted material is highly infectious and transmits infection to both cows and humans, but very little is known about how B. abortus causes abortion. By studying this infection in pregnant mice, we discovered that B. abortus kills trophoblasts, which are important cells for maintaining pregnancy. This killing required an injected bacterial protein (VceC) that triggered an endoplasmic reticulum (ER) stress response in the trophoblast. By inhibiting ER stress or infecting mice that lack CHOP, a protein induced by ER stress, we could prevent death of trophoblasts, reduce inflammation, and increase the viability of the pups. Our results suggest that B. abortus injects VceC into placental trophoblasts to promote its transmission by abortion
Stakeholdersâ knowledge, attitudes and practices to pharmacovigilance and adverse drug reaction reporting in clinical trials: a mixed methods study
Purpose: The purpose of this study was to explore the knowledge, attitudes and practices of health professionals working in clinical trials, to pharmacovigilance and adverse drug reaction (ADR) reporting. Methods: A mixed methods study comprising an online questionnaire disseminated from September to November 2018, three semi-structured interviews and four focus groups. The qualitative components were conducted with a random sample of questionnaire participants who had provided their contact details (n = 24). The qualitative interviews were conducted at a location convenient to the participantâs place of work between October and December 2018. Results: One hundred forty-eight participants completed the questionnaire. Study coordinators/project managers represented the largest group of participants ( 28.6%, n = 38). Poor knowledge or understanding of ADR reporting was the most frequently cited barrier to ADR reporting (75%, n = 93). The most common enabler to reporting was having a clear understanding of an ADR definition (85.7%, n = 108). Focus group and interview participants described having limited staff as a barrier to reporting an ADR. They welcomed the prospect of pharmacovigilance training and indicated that face-to-face training would be preferred to provision of online training. Conclusion: This study highlights key factors that influence the reporting of ADRs in clinical trials. Although the findings are specifically related to the clinical trial environment in Ireland, they may provide a useful platform for optimising the future conduct of trials. This research suggests that ADR reporting may be improved through provision of enhanced pharmacovigilance training to clinical trial staff
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