132 research outputs found
The role of MUC1 splice variants in dry eye and inflammation.
Mucin 1 (MUC1) is a plasma membrane-bound glycoprotein that plays a protective role in corneal epithelial cells. Two full-length splice variants of MUCl: MUCl/B and MUCl/A, that differ by the inclusion of 27 bp from intron 1 and a SNP in MUCl/A, but have identical C-terminal cytoplasmic domain (CD) sequences, were identified in human conjunctival tissue. I tested the hypothesis that MUC1 splice variants are key immunoregulators that act on the ocular surface to protect the ocular surface from inflammation and that their expression correlates with dry eye status. The expression of MUC1/A and MUCl/B splice variant was examined in non-Sjogren\u27s aqueous deficient and evaporative dry eye patients and compared to normal controls. The frequency of MUC1/A gene expression was lower in patients with non-Sjogren\u27s aqueous deficient dry eye compared to controls, indicating a link between MUC1/A and the symptoms associated with dry eye disease. Overexpression of MUC1/A and MUC1/B in COS-7 cells resulted in equal protein expression and plasma membrane localization. MUCl/B and MUCl/A splice variants differed in their ability to modulate the TNFa-induced inflammatory responses. The MUCl/B splice variant, and not MUCl/A, inhibited the induction of IL-1ß and IL-8 expression by TNFa at 4 h. In contrast, MUC1/A stimulated TNFa-driven IL-8 mRNA and protein expression after 24 h of treatment. MUC1/B, but not MUC1/A, inhibited TNFa-induced luciferase activity from an NF-KB reporter. Both MUC1/B and MUCl/A blocked the induction of miR-21 by TNFa. In addition, MUC1/A, but not MUCl/B, increased basal expression of TGFß. These data demonstrate for the first time that MUCl/A and MUC1/B are genetic susceptibility factors with different anti-inflammatory activities
Characterizing Metabolic Alterations in Palbociclib-Resistant ER+ Breast Cancer
Characterizing Metabolic Alterations in Palbociclib-Resistant ER+ Breast Cancer
Jessica Shunnarah1, Susan M. Dougherty2, Yoannis Imbert-Fernandez3
1ULBB Program, 2Department of Medicine, University of Louisville
Abstract
Diverse mechanisms of resistance to inhibitors of cyclin dependent kinases 4 and 6 (CDK4/6) have been described including cell cycle alterations and metabolic changes. Palbociclib was the first CDK4/6inhibitor approved against estrogen receptor positive (ER+) breast cancer however, the development of resistance has limited its success. This study investigates the changes in the expression of key metabolic enzymes using an in vivo model of palbociclib resistance. Palbociclib-resistant patient derive xenografts (PDXs) were generated by treating NSG mice that had ER+ breast cancer was implanted into the mammary fat pat of NSG mice with palbociclib until the tumors grew in the presence of the drug.. At endpoint, the tumors were harvested, flash frozen, and pulverized for western blot analysis. Our analysis shows the up regulation in some of the metabolic enzymes. We have concluded that resistance to palbociclib ER+ breast cancer increases the expression of Glutaminase (GLS1) in the presence and absence of palbociclib. Palbociclib treatment also leads to an increase 6-phosphofructo-2 kinase/fructose-2,6-biphosphotase-3 (PFKFB3) and Glucose-6-phosphate dehydrogenase (G6PDH) and transketolase in both palbociclib-sensitive and palbociclib-resistant PDX models.
Keywords: Palbociclib, estrogen receptor positive, patient derive xenograft, glutaminase, 6-phosphofructo-2 kinase/fructo, glucose-6-phosphate dehydrogenas
Fructose-2,6-Bisphosphate Synthesis by 6-Phosphofructo-2-Kinase/Fructose-2,6-Bisphosphatase 4 (PFKFB4) Is Required for the Glycolytic Response to Hypoxia and Tumor Growth
Fructose-2,6-bisphosphate (F2,6BP) is a shunt product of glycolysis that allosterically activates 6-phosphofructo-1-kinase (PFK-1) resulting in increased glucose uptake and glycolytic flux to lactate. The F2,6BP concentration is dictated by four bifunctional 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatases (PFKFB1-4) with distinct kinase:phosphatase activities. PFKFB4 is over-expressed in human cancers, induced by hypoxia and required for survival and growth of several cancer cell lines. Although PFKFB4 appears to be a rational target for anti-neoplastic drug development, it is not clear whether its kinase or phosphatase activity is required for cancer cell survival. In this study, we demonstrate that recombinant human PFKFB4 kinase activity is 4.3-fold greater than its phosphatase activity, siRNA and genomic deletion of PFKFB4 decrease F2,6BP, PFKFB4 over-expression increases F2,6BP and selective PFKFB4 inhibition in vivo markedly reduces F2,6BP, glucose uptake and ATP. Last, we find that PFKFB4 is required for cancer cell survival during the metabolic response to hypoxia, presumably to enable glycolytic production of ATP when the electron transport chain is not fully operational. Taken together, our data indicate that the PFKFB4 expressed in multiple transformed cells and tumors functions to synthesize F2,6BP. We predict that pharmacological disruption of the PFKFB4 kinase domain may have clinical utility for the treatment of human cancers
Analysis of labour market needs for engineers with enhanced knowledge in renewable energy in some European and Latin-American Countries
One of the main challenges related to the renewable energy labour market is that of human capital and as a consequence the educational profile of future employees is of paramount importance. Unfortunately, the skill level gained at University does not always fit with the practical needs of industry thus reducing the benefit-cost ratio of new employees and slowing down the transition to a green economy. Within this context, ‘The Crux’ project co-funded by EU under the framework of the Erasmus + programme aims at improving the renewable energy engineering curriculum at different university levels in several Universities of Latin America and Europe. In order to better appreciate the potential impact of the project, a survey on the labour market need for specialists with enhanced knowledge and skills in renewable and sustainable energy technologies has been conducted in the related EU and Latin America countries. More precisely, 60 organizations have been interviewed and almost 70% of them are interested in employing engineers with enhanced knowledge on renewable energy in the next three years. The analysis has shown significant discrepancies between EU and Latin American organizations. In fact, while future employees in EU countries will be mainly related to solar energy and management, the former together with wind and biomass will represent the main renewable energy working sector in Latin American countries. Moreover, MSc level will be the most demanded in EU while bachelor education seems to satisfy the future industry requirements in Latin America. Despite each country having its own needs, the research carried out under this EU project confirms the potential of renewable energy education on the global labour market in the near future
Supporting dynamic change detection: using the right tool for the task
Detecting task-relevant changes in a visual scene is necessary for successfully monitoring and managing dynamic command and control situations. Change blindness—the failure to notice visual changes—is an important source of human error. Change History EXplicit (CHEX) is a tool developed to aid change detection and maintain situation awareness; and in the current study we test the generality of its ability to facilitate the detection of changes when this subtask is embedded within a broader dynamic decision-making task. A multitasking air-warfare simulation required participants to perform radar-based subtasks, for which change detection was a necessary aspect of the higher-order goal of protecting one’s own ship. In this task, however, CHEX rendered the operator even more vulnerable to attentional failures in change detection and increased perceived workload. Such support was only effective when participants performed a change detection task without concurrent subtasks. Results are interpreted in terms of the NSEEV model of attention behavior (Steelman, McCarley, & Wickens, Hum. Factors 53:142–153, 2011; J. Exp. Psychol. Appl. 19:403–419, 2013), and suggest that decision aids for use in multitasking contexts must be designed to fit within the available workload capacity of the user so that they may truly augment cognition
Early Presymptomatic and Long-Term Changes of Rest Activity Cycles and Cognitive Behavior in a MPTP-Monkey Model of Parkinson's Disease
It is increasingly recognized that non-motor symptoms are a prominent feature of Parkinson's disease and in the case of cognitive deficits can precede onset of the characteristic motor symptoms. Here, we examine in 4 monkeys chronically treated with low doses of the neurotoxin MPTP the early and long-term alterations of rest-activity rhythms in relationship to the appearance of motor and cognitive symptoms.Behavioral activity recordings as well as motor and cognitive assessments were carried out continuously and in parallel before, during and for several months following MPTP-treatment (12–56 weeks). Cognitive abilities were assessed using a task that is dependent on the functional integrity of the fronto-striatal axis. Rest-activity cycles were monitored continuously using infrared movement detectors of locomotor activity. Motor impairment was evaluated using standardized scales for primates. Results show that MPTP treatment led to an immediate alteration (within one week) of rest-activity cycles and cognitive deficits. Parkinsonian motor deficits only became apparent 3 to 5 weeks after initiating chronic MPTP administration. In three of the four animals studied, clinical scores returned to control levels 5–7 weeks following cessation of MPTP treatment. In contrast, both cognitive deficits and chronobiological alterations persisted for many months. Levodopa treatment led to an improvement of cognitive performance but did not affect rest-activity rhythms in the two cases tested.Present results show that i) changes in the rest activity cycles constituted early detectable consequences of MPTP treatment and, along with cognitive alterations, characterize the presymptomatic stage; ii) following motor recovery there is a long-term persistence of non-motor symptoms that could reflect differential underlying compensatory mechanisms in these domains; iii) the progressive MPTP-monkey model of presymptomatic ongoing parkinsonism offers possibilities for in-depth studies of early non-motor symptoms including sleep alterations and cognitive deficits
Demographic, clinical and antibody characteristics of patients with digital ulcers in systemic sclerosis: data from the DUO Registry
OBJECTIVES: The Digital Ulcers Outcome (DUO) Registry was designed to describe the clinical and antibody characteristics, disease course and outcomes of patients with digital ulcers associated with systemic sclerosis (SSc).
METHODS: The DUO Registry is a European, prospective, multicentre, observational, registry of SSc patients with ongoing digital ulcer disease, irrespective of treatment regimen. Data collected included demographics, SSc duration, SSc subset, internal organ manifestations, autoantibodies, previous and ongoing interventions and complications related to digital ulcers.
RESULTS: Up to 19 November 2010 a total of 2439 patients had enrolled into the registry. Most were classified as either limited cutaneous SSc (lcSSc; 52.2%) or diffuse cutaneous SSc (dcSSc; 36.9%). Digital ulcers developed earlier in patients with dcSSc compared with lcSSc. Almost all patients (95.7%) tested positive for antinuclear antibodies, 45.2% for anti-scleroderma-70 and 43.6% for anticentromere antibodies (ACA). The first digital ulcer in the anti-scleroderma-70-positive patient cohort occurred approximately 5 years earlier than the ACA-positive patient group.
CONCLUSIONS: This study provides data from a large cohort of SSc patients with a history of digital ulcers. The early occurrence and high frequency of digital ulcer complications are especially seen in patients with dcSSc and/or anti-scleroderma-70 antibodies
Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases
The production of peroxide and superoxide is an inevitable consequence of
aerobic metabolism, and while these particular "reactive oxygen species" (ROSs)
can exhibit a number of biological effects, they are not of themselves
excessively reactive and thus they are not especially damaging at physiological
concentrations. However, their reactions with poorly liganded iron species can
lead to the catalytic production of the very reactive and dangerous hydroxyl
radical, which is exceptionally damaging, and a major cause of chronic
inflammation. We review the considerable and wide-ranging evidence for the
involvement of this combination of (su)peroxide and poorly liganded iron in a
large number of physiological and indeed pathological processes and
inflammatory disorders, especially those involving the progressive degradation
of cellular and organismal performance. These diseases share a great many
similarities and thus might be considered to have a common cause (i.e.
iron-catalysed free radical and especially hydroxyl radical generation). The
studies reviewed include those focused on a series of cardiovascular, metabolic
and neurological diseases, where iron can be found at the sites of plaques and
lesions, as well as studies showing the significance of iron to aging and
longevity. The effective chelation of iron by natural or synthetic ligands is
thus of major physiological (and potentially therapeutic) importance. As
systems properties, we need to recognise that physiological observables have
multiple molecular causes, and studying them in isolation leads to inconsistent
patterns of apparent causality when it is the simultaneous combination of
multiple factors that is responsible. This explains, for instance, the
decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference
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