126 research outputs found
Co-hydrolysis of hydrothermal and dilute acid pretreated populus slurries to support development of a high-throughput pretreatment system
Background
The BioEnergy Science Center (BESC) developed a high-throughput screening method to rapidly identify low-recalcitrance biomass variants. Because the customary separation and analysis of liquid and solids between pretreatment and enzymatic hydrolysis used in conventional analyses is slow, labor-intensive and very difficult to automate, a streamlined approach we term 'co-hydrolysis' was developed. In this method, the solids and liquid in the pretreated biomass slurry are not separated, but instead hydrolysis is performed by adding enzymes to the whole pretreated slurry. The effects of pretreatment method, severity and solids loading on co-hydrolysis performance were investigated.
Results
For hydrothermal pretreatment at solids concentrations of 0.5 to 2%, high enzyme protein loadings of about 100 mg/g of substrate (glucan plus xylan) in the original poplar wood achieved glucose and xylose yields for co-hydrolysis that were comparable with those for washed solids. In addition, although poplar wood sugar yields from co-hydrolysis at 2% solids concentrations fell short of those from hydrolysis of washed solids after dilute sulfuric acid pretreatment even at high enzyme loadings, pretreatment at 0.5% solids concentrations resulted in similar yields for all but the lowest enzyme loading.
Conclusions
Overall, the influence of severity on susceptibility of pretreated substrates to enzymatic hydrolysis was clearly discernable, showing co-hydrolysis to be a viable approach for identifying plant-pretreatment-enzyme combinations with substantial advantages for sugar production
Impact of Polymorphisms in PTK2 on Intrinsic Muscle Strength
Abstract Title:
Impact of Polymorphisms in PTK2 on Intrinsic Muscle Strength
Primary Presenter Full Name:
Zachary Zeller
Co-presenter Full Name(s):
Click here to enter text.
Co-author Full Name(s):
Mohamed Al-Amoodi, Whitney Jones, Danny Lee, Steven Mckenzie, Helen Miller, Seth Stubblefied, Susan Knoblach, Heather Gordish-Dressman, Dustin Hittel, Laura L. Tosi
Abstract Text (should not exceed 400 words):
Recent studies have begun to search for correlations between genetic variations and muscle strength. One such study by Stebbings et al.1 examined two single nucleotide polymorphisms (SNPs)ârs7843014 and rs7460âon the PTK2 gene. The study found that genetic variation in the PTK2 gene impacts muscle-specific force, which is the force generated per unit of cross-sectional area of muscle. Muscle-specific force ultimately represents the intrinsic strength of a muscle and is a key determinant of functional capacity and mobility. This study sought to expand on prior research by looking for associations between genetic variants of PTK2 and measures of grip strength, as well as general anthropomorphic measures, in a cohort of healthy young adults.
Our study assessed phenotypes for height, weight, VO2 max, max grip strength, and body mass index (BMI) using the Assessing Inherited Markers of Metabolic Syndrome in the Young (AIMMY) University of Calgary subset of 190 healthy, primarily Caucasian, individuals between the ages of 18 and 35. DNA samples were genotyped using ThermoFisher Taqman SNP genotype assays, and underwent the Applied Biosystems 7900HT real-time polymerase chain reaction (PCR) process. Analysis of covariance (ANCOVA) models were used to perform statistical analysis to look for genotype-phenotype associations.
Unlike the findings by Stebbings et al.1 an association between the PTK2 genotypes and grip strength was not found. This could be due to the lower statistical power in the grip strength test, thus potentially indicating that grip strength and muscle-specific force do not measure similar parameters of muscle strength. Genetic variation in PTK2 has also been previously associated with VO2 max, but no association was found in the current study.
Positive associations were found between genetic variants rs7843014 and rs7460 in PTK2 and BMI, and between genetic variant rs7843014 and height. High levels of functioning PTK2 have been found to have increased strength due to increased costamere density, resulting in more muscle myofibrils, and therein larger, presumably heavier muscles. However, this finding was only observed in males, and could be attributed to differential acquisition and maintenance of muscle mass based on sex.
We identified a potentially novel association between genetic variants in PTK2 and anthropomorphic phenotypes. However, we were unable to confirm the effects of genetic variants on measures of intrinsic muscle strength, namely max grip strength or VO2 max in terms of functional capacity. Further research is needed to confirm this newly identified role for PTK2
The association of polymorphism rs3736228 within the LRP5 gene with Bone Mineral Density in a Cohort of Caucasian Young Adults
INTRODUCTION: Osteoporosis is a significant burden for our aging population. Developing a better understanding of the genetic underpinnings of poor bone quality may assist in the future development of prevention strategies. Correa-Rodriguez et al. have identified a group of single nucleotide polymorphisms (SNPs) that were associated with bone mineral density (BMD) in a population of Spanish Caucasians. In particular, they found that SNP rs3736228 in the low-density lipoprotein receptor related protein 5 (LRP5) gene had an influence on BMD. While the role of LRP5 in the Wnt canonical pathway has been fairly well characterized, its association with phenotypic BMD and osteoporosis has only been explored in a limited fashion. The aim of this study is to expand on this, and to replicate the findings of previous studies in a cohort of healthy young adults.
METHODS: Cohort: The University of Calgary cohort from the Assessing Inherited Metabolic Syndrome Markers in the Young (UC AIMMY) study. Participants included consist of 168 healthy, predominantly Caucasian young adults. Phenotypes: height, weight, BMI, and total BMD. Genotyping: Allelic discrimination was determined. Statistical Analysis: After being tested for Hardy-Weinberg equilibrium (HWE), the data was run through analysis of covariance (ANCOVA).
RESULTS: Using a dominant model, we found that females with one or more copies of the risk T allele of SNP rs3736228 had a significant negative association with total BMD (p = 0.0347). However, a similar association was not seen in males in this cohort. We did not find a significant association for this polymorphism and height, weight, or BMI.
DISCUSSION: Polymorphisms in rs3736228 alter the codon in position 1330, downregulating the LRP5 cell surface receptor function. The LRP5 gene has now been shown in multiple studies to be associated with bone quality measures like calcaneal Qualitative Ultrasound (QUS) and BMD. Our study suggests that SNP rs3736228 also influences BMD in healthy young females. This supports the work of Correa-Rodriguez et al that found that when stratifying by sex, females only showed a trend towards significance (p = 0.092) in QUS measures.
SIGNIFICANCE: This study expands our understanding of the importance of LRP5 rs3736228 polymorphisms in BMD by extending its relationship to a cohort of predominantly Caucasian college students. While the development of BMD is polygenic, this work broadened the role of SNP rs3736228 across the age span, and the sexual dimorphism seen in musculoskeletal traits
Banff 2022 liver group meeting report: monitoring long term allograft health.
The Banff Working Group on Liver Allograft Pathology met in September 2022. Participantsincluded hepatologists, surgeons, pathologists, immunologists and histocompatibility specialists.Presentations and discussions focused on the evaluation of long-term allograft health, including noninvasive and tissue monitoring, immunosuppression optimisation and long-term structural changes.Potential revision of the rejection classification scheme to better accommodate and communicate lateT cell-mediated rejection patterns and related structural changes, such as nodular regenerativehyperplasia, were discussed. Improved stratification of long-term maintenance immunosuppression tomatch the heterogeneity of patient settings will be central to improving long-term patient survival.Such personalised therapeutics are in turn contingent on better understanding and monitoring ofallograft status within a rational decision-making approach, likely to be facilitated in implementationwith emerging decision support tools. Proposed revisions to rejection classification emerging fromthe meeting include incorporation of interface hepatitis and fibrosis staging. These will be opened toonline testing, modified accordingly and subject to consensus discussion leading up to the next Banffconference
A guide to using the Theoretical Domains Framework of behaviour change to investigate implementation problems
Background: Implementing new practices requires changes in the behaviour of relevant actors, and this is facilitated by understanding of the determinants of current and desired behaviours. The Theoretical Domains Framework (TDF) was developed by a collaboration of behavioural scientists and implementation researchers who identified theories relevant to implementation and grouped constructs from these theories into domains. The collaboration aimed to provide a comprehensive, theory-informed approach to identify determinants of behaviour. The first version was published in 2005, and a subsequent version following a validation exercise was published in 2012. This guide offers practical guidance for those who wish to apply the TDF to assess implementation problems and support intervention design. It presents a brief rationale for using a theoretical approach to investigate and address implementation problems, summarises the TDF and its development, and describes how to apply the TDF to achieve implementation objectives. Examples from the implementation research literature are presented to illustrate relevant methods and practical considerations.
Methods: Researchers from Canada, the UK and Australia attended a 3-day meeting in December 2012 to build an international collaboration among researchers and decision-makers interested in the advancing use of the TDF. The participants were experienced in using the TDF to assess implementation problems, design interventions, and/or understand change processes. This guide is an output of the meeting and also draws on the a uthors' collective experience. Examples from the implementation research literature judged by authors to be representative of specific applications of the TDF are included in this guide.
Results: We explain and illustrate methods, with a focus on qualitative approaches, for selecting and specifying target behaviours key to implementation, selecting the study design, deciding the sampling strategy, developing study materials, collecting and analysing data, and reporting findings of TDF-based studies. Areas for development include methods for triangulating data, e.g. from interviews, questionnaires and observation and methods for designing interventions based on TDF-based problem analysis.
Conclusions: We offer this guide to the implementation community to assist in the application of the TDF to achieve implementation objectives. Benefits of using the TDF include the provision of a theoretical basis for implementation studies, good coverage of potential reasons for slow diffusion of evidence into practice and a method for progressing from theory-based investigation to intervention
A modified Delphi study of screening for fetal alcohol spectrum disorders in Australia
Background: There is little reliable information on the prevalence of fetal alcohol spectrum disorders (FASD) in Australia and no coordinated national approach to facilitate case detection. The aim of this study was to identify health professionalsâ perceptions about screening for FASD in Australia. Method: A modified Delphi process was used to assess perceptions of the need for, and the process of, screening for FASD in Australia. We recruited a panel of 130 Australian health professionals with experience or expertise in FASD screening or diagnosis. A systematic review of the literature was used to develop Likert statements on screening coverage, components and assessment methods which were administered using an online survey over two survey rounds. Results: Of the panel members surveyed, 95 (73%) responded to the questions on screening in the first survey round and, of these, 81 (85%) responded to the second round. Following two rounds there was consensus agreement on the need for targeted screening at birth (76%) and in childhood (84%). Participants did not reach consensus agreement on the need for universal screening at birth (55%) or in childhood (40%). Support for targeted screening was linked to perceived constraints on service provision and the need to examine the performance, costs and benefits of screening. For targeted screening of high risk groups, we found highest agreement for siblings of known cases of FASD (96%) and children of mothers attending alcohol treatment services (93%). Participants agreed that screening for FASD primarily requires assessment of prenatal alcohol exposure at birth (86%) and in childhood (88%), and that a checklist is needed to identify the components of screening and criteria for referral at birth (84%) and in childhood (90%). Conclusions: There is an agreed need for targeted but not universal screening for FASD in Australia, and sufficient consensus among health professionals to warrant development and evaluation of standardised methods for targeted screening and referral in the Australian context. Participants emphasised the need for locally-appropriate, evidence-based approaches to facilitate case detection, and the importance of ensuring that screening and referral programs are supported by adequate diagnostic and management capacity
Fetal alcohol spectrum disorder: development of concensus referral criteria for specialist diagnostic assessment in Australia
Background: Fetal alcohol spectrum disorder (FASD) is known to be under-recognised in Australia. The use of standard methods to identify when to refer individuals who may have FASD for specialist assessment could help improve the identification of this disorder. The purpose of this study was to develop referral criteria for use in Australia. Method: An online survey about FASD screening and diagnosis in Australia, which included 23 statements describing criteria for referral for fetal alcohol syndrome (FAS) and FASD based on published recommendations for referral in North America, was sent to 139 health professionals who had expertise or involvement in FASD screening or diagnosis. Survey findings and published criteria for referral were subsequently reviewed by a panel of 14 investigators at a consensus development workshop where criteria for referral were developed.Results: Among the 139 health professionals who were sent the survey, 103 (74%) responded, and 90 (65%) responded to the statements on criteria for referral. Over 80% of respondents agreed that referral for specialist evaluation should occur when there is evidence of significant prenatal alcohol exposure, defined as 7 or more standard drinks per week and at least 3 standard drinks on any one day, and more than 70% agreed with 13 of the16 statements that described criteria for referral other than prenatal alcohol exposure. Workshop participants recommended five independent criteria for referral: confirmed significant prenatal alcohol exposure; microcephaly and confirmed prenatal alcohol exposure; 2 or more significant central nervous system (CNS) abnormalities and confirmed prenatal alcohol exposure; 3 characteristic FAS facial anomalies; and 1 characteristic FAS facial anomaly, growth deficit and 1 or more CNS abnormalities .Conclusion: Referral criteria recommended for use in Australia are similar to those recommended in North America. There is a need to develop resources to raise awareness of these criteria among health professionals and evaluate their feasibility, acceptability and capacity to improve the identification of FASD in Australia
Conserved Molecular Underpinnings and Characterization of a Role for Caveolin-1 in the Tumor Microenvironment of Mature T-Cell Lymphomas
Neoplasms of extra-thymic T-cell origin represent a rare and difficult population characterized by poor clinical outcome, aggressive presentation, and poorly defined molecular characteristics. Much work has been done to gain greater insights into distinguishing features among malignant subtypes, but there also exists a need to identify unifying characteristics to assist in rapid diagnosis and subsequent potential treatment. Herein, we investigated gene expression data of five different mature T-cell lymphoma subtypes (n = 187) and found 21 genes to be up- and down-regulated across all malignancies in comparison to healthy CD4+ and CD8+ T-cell controls (n = 52). From these results, we sought to characterize a role for caveolin-1 (CAV1), a gene with previous description in the progression of both solid and hematological tumors. Caveolin-1 was upregulated, albeit with a heterogeneous nature, across all mature T-cell lymphoma subtypes, a finding confirmed using immunohistochemical staining on an independent sampling of mature T-cell lymphoma biopsies (n = 65 cases). Further, stratifying malignant samples in accordance with high and low CAV1 expression revealed that higher expression of CAV1 in mature T-cell lymphomas is analogous with an enhanced inflammatory and invasive gene expression profile. Taken together, these results demonstrate a role for CAV1 in the tumor microenvironment of mature T-cell malignancies and point toward potential prognostic implications
Laser Interferometer Space Antenna
Following the selection of The Gravitational Universe by ESA, and the
successful flight of LISA Pathfinder, the LISA Consortium now proposes a 4 year
mission in response to ESA's call for missions for L3. The observatory will be
based on three arms with six active laser links, between three identical
spacecraft in a triangular formation separated by 2.5 million km.
LISA is an all-sky monitor and will offer a wide view of a dynamic cosmos
using Gravitational Waves as new and unique messengers to unveil The
Gravitational Universe. It provides the closest ever view of the infant
Universe at TeV energy scales, has known sources in the form of verification
binaries in the Milky Way, and can probe the entire Universe, from its smallest
scales near the horizons of black holes, all the way to cosmological scales.
The LISA mission will scan the entire sky as it follows behind the Earth in its
orbit, obtaining both polarisations of the Gravitational Waves simultaneously,
and will measure source parameters with astrophysically relevant sensitivity in
a band from below Hz to above Hz.Comment: Submitted to ESA on January 13th in response to the call for missions
for the L3 slot in the Cosmic Vision Programm
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