248 research outputs found
HEALTH VALUE IN FOOD SAFETY SURVEILLANCE INITIATIVES
Recognizing the increasing concern about the potential health effects of genetically modified foods, this research provides a framework for economic value of monitoring genetically modified food for their potential long-term human health effects. This is with the view of helping policy makers improve resource allocation decisions in the face of competing public health initiatives. Using a hypothetical population exposed to a hypothetical product, we estimate the health value associated with a post-market surveillance initiative. The analysis indicate that the principal challenge confronting decision makers in the implementation of post-market surveillance initiatives is prioritising products for monitoring given the uncertainty associated with outcomes and effects.Food Consumption/Nutrition/Food Safety,
Tracking the Fine Scale Movements of Fish using Autonomous Maritime Robotics: A Systematic State of the Art Review
This paper provides a systematic state of the art review on tracking the fine scale movements of fish with the use of autonomous maritime robotics. Knowledge of migration patterns and the localization of specific species of fish at a given time is vital to many aspects of conservation. This paper reviews these technologies and provides insight into what systems are being used and why. The review results show that a larger amount of complex systems that use a deep learning techniques are used over more simplistic approaches to the design. Most results found in the study involve Autonomous Underwater Vehicles, which generally require the most complex array of sensors. The results also provide insight into future research such as methods involving swarm intelligence, which has seen an increase in use in recent years. This synthesis of current and future research will be helpful to research teams working to create an autonomous vehicle with intentions to track, navigate or survey
Extending Peer-to-Peer Networks for Approximate Search
Peer-to-Peer (P2P) networks are used worldwide for many applications such as file sharing or news servers. There are many different implementations available, each with its pros and cons. In this paper, we propose a way to enable approximate queries in a P2P network by using a special encoding function and error correcting codes. The encoding function maintains neighborhood relationships so that two similar inputs will result in two similar outputs. The error correcting code is then used to group the similar encoded values around special codewords. In this manner, similar content is located as close as possible in the network. The algorithm is tested in a simulated environment on a HyperCube type network overlay in order to see if it can be a viable solution in a real network
Identification and characterization of Dlc1 isoforms in the mouse and study of the biological function of a single gene trapped isoform
<p>Abstract</p> <p>Background</p> <p>The Dlc1 (deleted in liver cancer 1) tumour suppressor gene codes for a RhoGTPase activating protein that is found inactivated in many tumour types. Several transcriptional isoforms have been described but the functional significance and tissue distribution of each form is presently poorly understood. Also, differences in the number of isoforms and splice variants reported still exist between different mammalian species. In order to better understand the number and function of the different variants of the Dlc1 gene in the mouse, we have carried out a detailed analysis. Extensive 3' RACE experiments were carried out in order to identify all possible Dlc1 isoforms and splice variants in the mouse. In addition, we have generated a gene trapped mouse that targets one of these isoforms in order to study its biological function. The effect of this gene trap insertion on the splicing of other isoforms has also been studied.</p> <p>Results</p> <p>In addition to the known 6.1 and 6.2 Kb transcripts of Dlc1, our study revealed the existence of a novel 7.6 Kb transcriptional isoform in the mouse, which corresponds to the human 7.4 Kb (KIAA1723) cDNA transcript. A gene trapped embryonic cell line, with an insertion between Exon 1 and 2 of the 6.1 Kb transcriptional isoform, was used to generate a transgenic mouse. This line showed a significant reduction in the expression of the trapped isoform. However, reduced expression of the other isoforms was not seen. Mice heterozygous for the gene trapped allele were phenotypically normal, but homozygous mutant embryos did not survive beyond 10.5 days post coitum. Dlc1<sup>gt/gt </sup>embryos showed defects in the brain, heart, and placental blood vessels. Cultured serum-free mouse embryo cells from Dlc1 deficient embryos had elevated RhoA activity and displayed alterations in the organization of actin filaments and focal adhesions. The Dlc1 deficient cells also exhibited increased wound closure in an <it>in vitro </it>scratch assay.</p> <p>Conclusions</p> <p>The mouse has three major transcriptional isoforms of the Dlc1 gene that are differentially expressed in various tissues. A mouse with exon 1 of the 6.1 Kb transcript gt resulted in hypomorphic expression of Dlc1 protein and an embryonic lethal phenotype in the homozygous condition, which indicates that this isoform plays a major role in mouse development. The Dlc1 deficient cells showed altered cytoskeleton structure, increased RhoA activity and cellular migration.</p
Dystrophin Gene Mutation Location and the Risk of Cognitive Impairment in Duchenne Muscular Dystrophy
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88828.pdf (publisher's version ) (Open Access)BACKGROUND: A significant component of the variation in cognitive disability that is observed in Duchenne muscular dystrophy (DMD) is known to be under genetic regulation. In this study we report correlations between standardised measures of intelligence and mutational class, mutation size, mutation location and the involvement of dystrophin isoforms. METHODS AND RESULTS: Sixty two male subjects were recruited as part of a study of the cognitive spectrum in boys with DMD conducted at the Sydney Children's Hospital (SCH). All 62 children received neuropsychological testing from a single clinical psychologist and had a defined dystrophin gene (DMD) mutation; including DMD gene deletions, duplications and DNA point mutations. Full Scale Intelligence Quotients (FSIQ) in unrelated subjects with the same mutation were found to be highly correlated (r = 0.83, p = 0.0008), in contrast to results in previous publications. In 58 cases (94%) it was possible to definitively assign a mutation as affecting one or more dystrophin isoforms. A strong association between the risk of cognitive disability and the involvement of groups of DMD isoforms was found. In particular, improvements in the correlation of FSIQ with mutation location were identified when a new classification system for mutations affecting the Dp140 isoform was implemented. SIGNIFICANCE: These data represent one of the largest studies of FSIQ and mutational data in DMD patients and is among the first to report on a DMD cohort which has had both comprehensive mutational analysis and FSIQ testing through a single referral centre. The correlation between FSIQ results with the location of the dystrophin gene mutation suggests that the risk of cognitive deficit is a result of the cumulative loss of central nervous system (CNS) expressed dystrophin isoforms, and that correct classification of isoform involvement results in improved estimates of risk
The dynamics of cardiolipin synthesis post-mitochondrial fusion
AbstractAlteration in mitochondrial fusion may regulate mitochondrial metabolism. Since the phospholipid cardiolipin (CL) is required for function of the mitochondrial respiratory chain, we examined the dynamics of CL synthesis in growing Hela cells immediately after and 12h post-fusion. Cells were transiently transfected with Mfn-2, to promote fusion, or Mfn-2 expressing an inactive GTPase for 24h and de novo CL biosynthesis was examined immediately after or 12h post-fusion. Western blot analysis confirmed elevated Mfn-2 expression and electron microscopic analysis revealed that Hela cell mitochondrial structure was normal immediately after and 12h post-fusion. Cells expressing Mfn-2 exhibited reduced CL de novo biosynthesis from [1,3-3H]glycerol immediately after fusion and this was due to a decrease in phosphatidylglycerol phosphate synthase (PGPS) activity and its mRNA expression. In contrast, 12h post-mitochondrial fusion cells expressing Mfn-2 exhibited increased CL de novo biosynthesis from [1,3-3H]glycerol and this was due to an increase in PGPS activity and its mRNA expression. Cells expressing Mfn-2 with an inactive GTPase activity did not exhibit alterations in CL de novo biosynthesis immediately after or 12h post-fusion. The Mfn-2 mediated alterations in CL de novo biosynthesis were not accompanied by alterations in CL or monolysoCL mass. [1-14C]Oleate incorporation into CL was elevated at 12h post-fusion indicating increased CL resynthesis. The reason for the increased CL resynthesis was an increased mRNA expression of tafazzin, a mitochondrial CL resynthesis enzyme. Ceramide-induced expression of PGPS in Hela cells or in CHO cells did not alter expression of Mfn-2 indicating that Mfn-2 expression is independent of altered CL synthesis mediated by elevated PGPS. In addition, Mfn-2 expression was not altered in Hela cells expressing phospholipid scramblase-3 or a disrupted scramblase indicating that proper CL localization within mitochondria is not essential for Mfn-2 expression. The results suggest that immediately post-mitochondrial fusion CL de novo biosynthesis is “slowed down” and then 12h post-fusion it is “upregulated”. The implications of this are discussed
Functional inhibition of acid sphingomyelinase by Fluphenazine triggers hypoxia-specific tumor cell death
Owing to lagging or insufficient neo-angiogenesis, hypoxia is a feature of most solid tumors. Hypoxic tumor regions contribute to resistance against antiproliferative chemotherapeutics, radiotherapy and immunotherapy. Targeting cells in hypoxic tumor areas is therefore an important strategy for cancer treatment. Most approaches for targeting hypoxic cells focus on the inhibition of hypoxia adaption pathways but only a limited number of compounds with the potential to specifically target hypoxic tumor regions have been identified. By using tumor spheroids in hypoxic conditions as screening system, we identified a set of compounds, including the phenothiazine antipsychotic Fluphenazine, as hits with novel mode of action. Fluphenazine functionally inhibits acid sphingomyelinase and causes cellular sphingomyelin accumulation, which induces cancer cell death specifically in hypoxic tumor spheroids. Moreover, we found that functional inhibition of acid sphingomyelinase leads to overactivation of hypoxia stress-response pathways and that hypoxia-specific cell death is mediated by the stress-responsive transcription factor ATF4. Taken together, the here presented data suggest a novel, yet unexplored mechanism in which induction of sphingolipid stress leads to the overactivation of hypoxia stress-response pathways and thereby promotes their pro-apoptotic tumor-suppressor functions to specifically kill cells in hypoxic tumor areas
Use of electronic medical records (EMR) for oncology outcomes research: assessing the comparability of EMR information to patient registry and health claims data
Electronic medical records (EMRs) are used increasingly for research in clinical oncology, epidemiology, and comparative effectiveness research (CER)
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Sugar-Sweetened Beverage Intake and Cancer Recurrence and Survival in CALGB 89803 (Alliance)
Background: In colon cancer patients, obesity, sedentary lifestyle, and high dietary glycemic load have been associated with increased risk of cancer recurrence. High sugar-sweetened beverage intake has been associated with obesity, diabetes, and cardio-metabolic diseases, but the influence on colon cancer survival is unknown. Methods: We assessed the association between sugar-sweetened beverage consumption on cancer recurrence and mortality in 1,011 stage III colon cancer patients who completed food frequency questionnaires as part of a U.S. National Cancer Institute-sponsored adjuvant chemotherapy trial. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated with Cox proportional hazard models. Results: Patients consuming ≥2 servings of sugar-sweetened beverages per day experienced an adjusted HR for disease recurrence or mortality of 1.67 (95% CI, 1.04–2.68), compared with those consuming <2 servings per month (Ptrend = 0.02). The association of sugar-sweetened beverages on cancer recurrence or mortality appeared greater among patients who were both overweight (body mass index ≥25 kg/m2) and less physically active (metabolic equivalent task-hours per week <18) (HR = 2.22; 95% CI, 1.29–3.81, Ptrend = 0.0025). Conclusion: Higher sugar-sweetened beverage intake was associated with a significantly increased risk of cancer recurrence and mortality in stage III colon cancer patients
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