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1.
Assist Technol ; : 1-13, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38630052

ABSTRACT

This paper analyzes the technology-related outputs from The National Institute of Disability, Independent Living, and Rehabilitation Research (NIDILRR). We seek to answer the questions: What are the types and frequency of assistive technology (AT) technology transfer (ATTT) outputs from NIDILRR grants? How does NIDILRR's ATTT generation compare to other granting organizations? What types of ATTT outputs occur, how, and what is the relative productivity of the most frequently funded universities and small businesses performing with funding by NIDILRR grants? An online search was conducted for indications of ATTT from grants funded from 1983-2021 through publicly available databases, the National Rehabilitation Information Center (NARIC), and the internet. This data was then categorized across relevant output types and analyzed. NIDILRR funded 662 organizations and 951 different investigators from 1983 to 2021. The NIDILRR-funded portfolio includes 6,996 papers, 438 informational websites, 163 patents, 120 software products, and 29 hardware products. Compared to the National Institutes of Health (NIH), NIDILRR produced slightly more products per dollar. Our results highlight the substantial portfolio of technology-related outputs generated with NIDILRR funding and demonstrate how productivity measures can be calculated to guide future funding strategies.

2.
Plant Genome ; 16(4): e20397, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37885362

ABSTRACT

Vernalization requirement is an integral component of flowering in winter-type plants. The availability of winter ecotypes among Camelina species facilitated the mapping of quantitative trait loci (QTL) for vernalization requirement in Camelina sativa. An inter and intraspecific crossing scheme between related Camelina species, where one spring and two different sources of winter-type habit were used, resulted in the development of two segregating populations. Linkage maps generated with sequence-based markers identified three QTLs associated with vernalization requirement in C. sativa; two from the interspecific (chromosomes 13 and 20) and one from the intraspecific cross (chromosome 8). Notably, the three loci were mapped to different homologous regions of the hexaploid C. sativa genome. All three QTLs were found in proximity to Flowering Locus C (FLC), variants of which have been reported to affect the vernalization requirement in plants. Temporal transcriptome analysis for winter-type Camelina alyssum demonstrated reduction in expression of FLC on chromosomes 13 and 20 during cold treatment, which would trigger flowering, since FLC would be expected to suppress floral initiation. FLC on chromosome 8 also showed reduced expression in the C. sativa ssp. pilosa winter parent upon cold treatment, but was expressed at very high levels across all time points in the spring-type C. sativa. The chromosome 8 copy carried a deletion in the spring-type line, which could impact its functionality. Contrary to previous reports, all three FLC loci can contribute to controlling the vernalization response in C. sativa and provide opportunities for manipulating this requirement in the crop.


Subject(s)
Arabidopsis , Quantitative Trait Loci , Vernalization , Flowers , Chromosome Mapping , Arabidopsis/genetics
3.
Cell Signal ; 107: 110676, 2023 07.
Article in English | MEDLINE | ID: mdl-37028778

ABSTRACT

Asymmetric dimethylarginine (ADMA) is generated through the irreversible methylation of arginine residues. It is an independent risk factor for cardiovascular disease, currently thought to be due to its ability to act as a competitive inhibitor of the nitric oxide (NO) synthase enzymes. Plasma ADMA concentrations increase with obesity and fall following weight loss; however, it is unknown whether they play an active role in adipose pathology. Here, we demonstrate that ADMA drives lipid accumulation through a newly identified NO-independent pathway via the amino-acid sensitive calcium-sensing receptor (CaSR). ADMA treatment of 3T3-L1 and HepG2 cells upregulates a suite of lipogenic genes with an associated increase in triglyceride content. Pharmacological activation of CaSR mimics ADMA while negative modulation of CaSR inhibits ADMA driven lipid accumulation. Further investigation using CaSR overexpressing HEK293 cells demonstrated that ADMA potentiates CaSR signalling via Gq intracellular Ca2+ mobilisation. This study identifies a signalling mechanism for ADMA as an endogenous ligand of the G protein-coupled receptor CaSR that potentially contributes to the impact of ADMA in cardiometabolic disease.


Subject(s)
Arginine , Receptors, Calcium-Sensing , Humans , HEK293 Cells , Arginine/metabolism , Nitric Oxide Synthase/metabolism , Lipids
4.
Plant Biotechnol J ; 21(3): 521-535, 2023 03.
Article in English | MEDLINE | ID: mdl-36398722

ABSTRACT

Camelina neglecta is a diploid species from the genus Camelina, which includes the versatile oilseed Camelina sativa. These species are closely related to Arabidopsis thaliana and the economically important Brassica crop species, making this genus a useful platform to dissect traits of agronomic importance while providing a tool to study the evolution of polyploids. A highly contiguous chromosome-level genome sequence of C. neglecta with an N50 size of 29.1 Mb was generated utilizing Pacific Biosciences (PacBio, Menlo Park, CA) long-read sequencing followed by chromosome conformation phasing. Comparison of the genome with that of C. sativa shows remarkable coincidence with subgenome 1 of the hexaploid, with only one major chromosomal rearrangement separating the two. Synonymous substitution rate analysis of the predicted 34 061 genes suggested subgenome 1 of C. sativa directly descended from C. neglecta around 1.2 mya. Higher functional divergence of genes in the hexaploid as evidenced by the greater number of unique orthogroups, and differential composition of resistant gene analogs, might suggest an immediate adaptation strategy after genome merger. The absence of genome bias in gene fractionation among the subgenomes of C. sativa in comparison with C. neglecta, and the complete lack of fractionation of meiosis-specific genes attests to the neopolyploid status of C. sativa. The assembled genome will provide a tool to further study genome evolution processes in the Camelina genus and potentially allow for the identification and exploitation of novel variation for Camelina crop improvement.


Subject(s)
Arabidopsis , Brassica , Brassicaceae , Neglecta , Diploidy , Brassicaceae/genetics , Arabidopsis/genetics , Brassica/genetics , Genome, Plant
5.
Disabil Rehabil Assist Technol ; : 1-7, 2022 Sep 22.
Article in English | MEDLINE | ID: mdl-36136917

ABSTRACT

PURPOSE: The objectives of this mixed-methods study were to gather survey and interview data about the barriers and facilitators from grantees funded by the National Institute on Disability, Independent Living, and Rehabilitation Research (NIDILRR) and to extract themes that could inform program changes that would increase technology translation (TT) success in assistive technology (AT). MATERIALS AND METHODS: We developed a TT Barriers and Facilitators survey consisting of Likert scale and multiple-choice questions about barriers and facilitators to TT. With survey respondents who were willing, we conducting a semi-structured interview and asked pointed questions to expand upon survey response rankings and perceived barriers and facilitators. The questions were framed to explore the grantee's personal experience with ATTT and what helped and hindered their individualised processes. RESULTS: Across survey and interview respondents, the three most common themes when exploring the barriers and facilitators of TT were funding, incentives, and collaboration. CONCLUSIONS: Results indicate that there is a need for increased collaboration and access to additional resources such as funding for pilot grants, support to assess technology marketability, help to navigate regulatory and legal aspects, and assistance in establishing goals to help grantees successfully transfer assistive technologies to consumers. IMPLICATIONS FOR REHABILITATIONA large amount of research and development into assistive technology does not lead to tech transfer which means that these technologies are not getting to the people that need them.Educating tech transfer offices at universities about how to transfer AT would improve outcomes greatly.Creating a community of practice where grantees can find academic or industry partners would also increase the likelihood of tech transfer.Some tools to catalyse these improvements are: mentoring, access to consultants, podcasts, and online training.

6.
Bioorg Med Chem Lett ; 39: 127873, 2021 05 01.
Article in English | MEDLINE | ID: mdl-33631369

ABSTRACT

Quorum sensing is a bacterial signaling system that involves the synthesis, secretion and detection of signal molecules called autoinducers. The main autoinducer in Gram-negative bacteria are acylated homoserine lactones, produced by the LuxI family of autoinducer synthases and detected by the LuxR family of autoinducer receptors. Quorum sensing allows for changes in gene expression and bacterial behaviors in a coordinated, cell density dependent manner. Quorum sensing controls the expression of virulence factors in some human pathogens, making quorum sensing an antibacterial drug target. Here we describe the design and synthesis of transition-state analogs of the autoinducer synthase enzymatic reaction and the evaluation of these compounds as inhibitors of the synthase CepI. One such compound potently inhibits CepI and constitutes a new type of inhibitor against this underdeveloped antibacterial target.


Subject(s)
Drug Design , Enzyme Inhibitors/pharmacology , Lactones/pharmacology , Ligases/antagonists & inhibitors , Dose-Response Relationship, Drug , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Lactones/chemical synthesis , Lactones/chemistry , Ligases/metabolism , Molecular Structure , Quorum Sensing/drug effects , Structure-Activity Relationship
7.
Eur J Radiol ; 136: 109534, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33454460

ABSTRACT

PURPOSE: This study assesses the rate of enhancement of breast fibroglandular tissue after administration of a magnetic resonance imaging (MRI) gadolinium-based contrast agent and determines its relationship with response to neoadjuvant therapy (NAT) in women with breast cancer. METHOD: Women with locally advanced breast cancer (N = 19) were imaged four times over the course of NAT. Dynamic contrast-enhanced (DCE) MRI was acquired after administration of a gadolinium-based contrast agent with a temporal resolution of 7.27 s. The tumor, fibroglandular tissue, and adipose tissue were semi-automatically segmented using a manually drawn region of interest encompassing the tumor followed by fuzzy c-means clustering. The rate and relative intensity of signal enhancement were calculated for each voxel within the tumor and fibroglandular tissue. RESULTS: The rate of fibroglandular tissue enhancement after contrast agent injection declined by an average of 29 % over the course of NAT. This decline was present in 16 of the 19 patients in the study. The rate of enhancement is significantly higher in women who achieve pathological complete response (pCR) after both 1 cycle (68 % higher, p < 0.05) and after 3-5 cycles of NAT (58 % higher; p < 0.05). The relative intensity of fibroglandular enhancement correlates with the rate of enhancement (R2 = 0.64, p < 0.001) and is higher in women who achieve pCR after both 1 cycle and after 3-5 cycles of NAT (p < 0.05, both timepoints). CONCLUSION: The rate of fibroglandular tissue enhancement declines over the course of therapy, provides novel information not reflected by tumoral measures, and may predict pathological response early in the course of therapy, with smaller declines in enhancement in women who achieve favorable response.


Subject(s)
Breast Neoplasms , Neoadjuvant Therapy , Breast/diagnostic imaging , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/drug therapy , Contrast Media , Female , Humans , Magnetic Resonance Imaging
8.
Front Plant Sci ; 12: 780250, 2021.
Article in English | MEDLINE | ID: mdl-35069637

ABSTRACT

Phenotyping is considered a significant bottleneck impeding fast and efficient crop improvement. Similar to many crops, Brassica napus, an internationally important oilseed crop, suffers from low genetic diversity, and will require exploitation of diverse genetic resources to develop locally adapted, high yielding and stress resistant cultivars. A pilot study was completed to assess the feasibility of using indoor high-throughput phenotyping (HTP), semi-automated image processing, and machine learning to capture the phenotypic diversity of agronomically important traits in a diverse B. napus breeding population, SKBnNAM, introduced here for the first time. The experiment comprised 50 spring-type B. napus lines, grown and phenotyped in six replicates under two treatment conditions (control and drought) over 38 days in a LemnaTec Scanalyzer 3D facility. Growth traits including plant height, width, projected leaf area, and estimated biovolume were extracted and derived through processing of RGB and NIR images. Anthesis was automatically and accurately scored (97% accuracy) and the number of flowers per plant and day was approximated alongside relevant canopy traits (width, angle). Further, supervised machine learning was used to predict the total number of raceme branches from flower attributes with 91% accuracy (linear regression and Huber regression algorithms) and to identify mild drought stress, a complex trait which typically has to be empirically scored (0.85 area under the receiver operating characteristic curve, random forest classifier algorithm). The study demonstrates the potential of HTP, image processing and computer vision for effective characterization of agronomic trait diversity in B. napus, although limitations of the platform did create significant variation that limited the utility of the data. However, the results underscore the value of machine learning for phenotyping studies, particularly for complex traits such as drought stress resistance.

9.
Front Plant Sci ; 12: 787354, 2021.
Article in English | MEDLINE | ID: mdl-35095961

ABSTRACT

Turnip mosaic virus (TuMV) induces disease in susceptible hosts, notably impacting cultivation of important crop species of the Brassica genus. Few effective plant viral disease management strategies exist with the majority of current approaches aiming to mitigate the virus indirectly through control of aphid vector species. Multiple sources of genetic resistance to TuMV have been identified previously, although the majority are strain-specific and have not been exploited commercially. Here, two Brassica juncea lines (TWBJ14 and TWBJ20) with resistance against important TuMV isolates (UK 1, vVIR24, CDN 1, and GBR 6) representing the most prevalent pathotypes of TuMV (1, 3, 4, and 4, respectively) and known to overcome other sources of resistance, have been identified and characterized. Genetic inheritance of both resistances was determined to be based on a recessive two-gene model. Using both single nucleotide polymorphism (SNP) array and genotyping by sequencing (GBS) methods, quantitative trait loci (QTL) analyses were performed using first backcross (BC1) genetic mapping populations segregating for TuMV resistance. Pairs of statistically significant TuMV resistance-associated QTLs with additive interactive effects were identified on chromosomes A03 and A06 for both TWBJ14 and TWBJ20 material. Complementation testing between these B. juncea lines indicated that one resistance-linked locus was shared. Following established resistance gene nomenclature for recessive TuMV resistance genes, these new resistance-associated loci have been termed retr04 (chromosome A06, TWBJ14, and TWBJ20), retr05 (A03, TWBJ14), and retr06 (A03, TWBJ20). Genotyping by sequencing data investigated in parallel to robust SNP array data was highly suboptimal, with informative data not established for key BC1 parental samples. This necessitated careful consideration and the development of new methods for processing compromised data. Using reductive screening of potential markers according to allelic variation and the recombination observed across BC1 samples genotyped, compromised GBS data was rendered functional with near-equivalent QTL outputs to the SNP array data. The reductive screening strategy employed here offers an alternative to methods relying upon imputation or artificial correction of genotypic data and may prove effective for similar biparental QTL mapping studies.

10.
New Phytol ; 229(6): 3281-3293, 2021 03.
Article in English | MEDLINE | ID: mdl-33020949

ABSTRACT

Ensuring faithful homologous recombination in allopolyploids is essential to maintain optimal fertility of the species. Variation in the ability to control aberrant pairing between homoeologous chromosomes in Brassica napus has been identified. The current study exploited the extremes of such variation to identify genetic factors that differentiate newly resynthesised B. napus, which is inherently unstable, and established B. napus, which has adapted to largely control homoeologous recombination. A segregating B. napus mapping population was analysed utilising both cytogenetic observations and high-throughput genotyping to quantify the levels of homoeologous recombination. Three quantitative trait loci (QTL) were identified that contributed to the control of homoeologous recombination in the important oilseed crop B. napus. One major QTL on BnaA9 contributed between 32 and 58% of the observed variation. This study is the first to assess homoeologous recombination and map associated QTLs resulting from deviations in normal pairing in allotetraploid B. napus. The identified QTL regions suggest candidate meiotic genes that could be manipulated in order to control this important trait and further allow the development of molecular markers to utilise this trait to exploit homoeologous recombination in a crop.


Subject(s)
Brassica napus , Brassica napus/genetics , Chromosomes, Plant/genetics , Genome, Plant , Polyploidy , Quantitative Trait Loci/genetics
11.
J Clin Med ; 9(9)2020 Sep 20.
Article in English | MEDLINE | ID: mdl-32962225

ABSTRACT

Atherosclerosis is a chronic cardiovascular disease which increases risk of major cardiovascular events including myocardial infarction and stroke. Elevated plasma concentrations of asymmetric dimethylarginine (ADMA) have long been recognised as a hallmark of cardiovascular disease and are associated with cardiovascular risk factors including hypertension, obesity and hypertriglyceridemia. In this review, we discuss the clinical literature that link ADMA concentrations to increased risk of the development of atherosclerosis. The formation of atherosclerotic lesions relies on the interplay between vascular dysfunction, leading to endothelial activation and the accumulation of inflammatory cells, particularly macrophages, within the vessel wall. Here, we review the mechanisms through which elevated ADMA contributes to endothelial dysfunction, activation and reactive oxygen species (ROS) production; how ADMA may affect vascular smooth muscle phenotype; and finally whether ADMA plays a regulatory role in the inflammatory processes occurring within the vessel wall.

12.
Nat Plants ; 6(8): 929-941, 2020 08.
Article in English | MEDLINE | ID: mdl-32782408

ABSTRACT

It is only recently, with the advent of long-read sequencing technologies, that we are beginning to uncover previously uncharted regions of complex and inherently recursive plant genomes. To comprehensively study and exploit the genome of the neglected oilseed Brassica nigra, we generated two high-quality nanopore de novo genome assemblies. The N50 contig lengths for the two assemblies were 17.1 Mb (12 contigs), one of the best among 324 sequenced plant genomes, and 0.29 Mb (424 contigs), respectively, reflecting recent improvements in the technology. Comparison with a de novo short-read assembly corroborated genome integrity and quantified sequence-related error rates (0.2%). The contiguity and coverage allowed unprecedented access to low-complexity regions of the genome. Pericentromeric regions and coincidence of hypomethylation enabled localization of active centromeres and identified centromere-associated ALE family retro-elements that appear to have proliferated through relatively recent nested transposition events (<1 Ma). Genomic distances calculated based on synteny relationships were used to define a post-triplication Brassica-specific ancestral genome, and to calculate the extensive rearrangements that define the evolutionary distance separating B. nigra from its diploid relatives.


Subject(s)
Brassica/genetics , Centromere/genetics , Genome, Plant/genetics , Mustard Plant/genetics , DNA, Plant/genetics , Evolution, Molecular , High-Throughput Nucleotide Sequencing
13.
Sci Rep ; 10(1): 12629, 2020 07 28.
Article in English | MEDLINE | ID: mdl-32724070

ABSTRACT

Ethiopian mustard (Brassica carinata A. Braun) is an emerging sustainable source of vegetable oil, in particular for the biofuel industry. The present study exploited genome assemblies of the Brassica diploids, Brassica nigra and Brassica oleracea, to discover over 10,000 genome-wide SNPs using genotype by sequencing of 620 B. carinata lines. The analyses revealed a SNP frequency of one every 91.7 kb, a heterozygosity level of 0.30, nucleotide diversity levels of 1.31 × 10-05, and the first five principal components captured only 13% molecular variation, indicating low levels of genetic diversity among the B. carinata collection. Genome bias was observed, with greater SNP density found on the B subgenome. The 620 lines clustered into two distinct sub-populations (SP1 and SP2) with the majority of accessions (88%) clustered in SP1 with those from Ethiopia, the presumed centre of origin. SP2 was distinguished by a collection of breeding lines, implicating targeted selection in creating population structure. Two selective sweep regions on B3 and B8 were detected, which harbour genes involved in fatty acid and aliphatic glucosinolate biosynthesis, respectively. The assessment of genetic diversity, population structure, and LD in the global B. carinata collection provides critical information to assist future crop improvement.


Subject(s)
Crops, Agricultural/genetics , Industry , Linkage Disequilibrium/genetics , Mustard Plant/genetics , Chromosomes, Plant/genetics , Genetic Variation , Genetics, Population , Genome, Plant , Haplotypes/genetics , Polymorphism, Single Nucleotide/genetics , Selection, Genetic
14.
Circ Genom Precis Med ; 12(11): e002648, 2019 11.
Article in English | MEDLINE | ID: mdl-31638832

ABSTRACT

BACKGROUND: MRAS was identified recently as a novel Noonan syndrome (NS)-susceptibility gene. Phenotypically, both patients with NS, harboring pathogenic MRAS variants, displayed severe cardiac hypertrophy. This study aimed to demonstrate both the necessity and sufficiency of a patient-specific variant (p.Gly23Val-MRAS) to cause NS through the generation and characterization of patient-specific, isogenic control, and disease modeled induced pluripotent stem cell (iPSC) lines. METHODS: iPSCs were derived from a patient with a p.Gly23Val-MRAS variant to assess the effect of MRAS variants on pathogenesis of NS-associated cardiac hypertrophy. CRISPR/Cas9 gene editing was used to correct the pathogenic p.Gly23Val-MRAS variant in patient cells (isogenic control) and to introduce the pathogenic variant into unrelated control cells (disease modeled) to determine the necessity and sufficiency of the p.Gly23Val-MRAS variant to elicit the disease phenotype in iPSC-derived cardiomyocytes (iPSC-CMs). iPSC-CMs were analyzed by microscopy and immunofluroesence, single-cell RNAseq, Western blot, room temperature-quantitative polymerase chain reaction, and live-cell calcium imaging to define an in vitro phenotype of MRAS-mediated cardiac hypertrophy. RESULTS: Compared with controls, both patient and disease modeled iPSC-CMs were significantly larger and demonstrated changes in gene expression and intracellular pathway signaling characteristic of cardiac hypertrophy. Additionally, patient and disease modeled iPSC-CMs displayed impaired Ca2+ handling, including increased frequency of irregular Ca2+ transients and changes in Ca2+ handling kinetics. CONCLUSIONS: p.Gly23Val-MRAS is both necessary and sufficient to elicit a cardiac hypertrophy phenotype in iPSC-CMs that includes increased cell size, changes in cardiac gene expression, and abnormal calcium handling-providing further evidence to establish the monogenetic pathogenicity of p.Gly23Val-MRAS in NS with cardiac hypertrophy.


Subject(s)
Cardiomegaly/genetics , Induced Pluripotent Stem Cells/metabolism , Myocytes, Cardiac/metabolism , Noonan Syndrome/genetics , ras Proteins/genetics , Base Sequence , Cardiomegaly/metabolism , Cells, Cultured , Female , Genetic Predisposition to Disease , Humans , Mutation , Phenotype , ras Proteins/metabolism
15.
Cureus ; 10(6): e2811, 2018 Jun 14.
Article in English | MEDLINE | ID: mdl-30116684

ABSTRACT

OBJECTIVE: To evaluate the impact of a simulation-based elective on medical student preparedness for obstetrics and gynecology (OB/GYN) residency. METHODS: A two-week, simulation-based elective course for post-clerkship medical students was developed, and 10 students participated at a single academic institution in 2016 and 2017. Using standardized patients and team-based training, students practiced procedural and surgical skills, as well as the diagnosis, management, and work-up of commonly seen problems. Close coaching with a low student-faculty ratio was employed for each session, allowing for individualized feedback in real time. Prior to and after completing the elective, student knowledge was evaluated using the Preparation for Residency Knowledge Assessment tool (PrepForRes). Written course evaluations were also completed by students at the end of the course. RESULTS: Mean scores on the PrepForRes exam increased from 63.6% to 75.3% (p=0.0136). Notably, the average post-course score improved to a passing level, and all but one student achieved a passing score on the post-course test. Course evaluations and student feedback showed high satisfaction rates with the course. CONCLUSIONS: This study demonstrates that a simulation-based elective course is an effective tool for helping medical students transition to OB/GYN residency. As medical schools work to facilitate the transition from undergraduate to graduate medical education, simulation can bridge gaps during this transition in order for students to meet entry-level residency requirements.

16.
Bioorg Chem ; 80: 560-564, 2018 10.
Article in English | MEDLINE | ID: mdl-30014924

ABSTRACT

The ketone body ester (R)-3-hydroxybutyryl-(R)-3-hydroxybutyrate and its (S,S) enantiomer were prepared in a short, operationally simple synthetic sequence from racemic ß-butyrolactone. Enantioselective hydrolysis of ß-butyrolactone with immobilized Candida antarctica lipase-B (CAL-B) results in (R)-ß-butyrolactone and (S)-ß-hydroxybutyric acid, which are easily converted to (R) or (S)-ethyl-3-hydroxybutyrate and reduced to (R) or (S)-1,3 butanediol. Either enantiomer of ethyl-3-hydroxybutyrate and 1,3 butanediol are then coupled, again using CAL-B, to produce the ketone body ester product. This is an efficient, scalable, atom-economic, chromatography-free, and low cost synthetic method to produce the ketone body esters.


Subject(s)
3-Hydroxybutyric Acid/chemistry , Ketones/chemistry , 3-Hydroxybutyric Acid/chemical synthesis , 4-Butyrolactone/analogs & derivatives , 4-Butyrolactone/chemical synthesis , 4-Butyrolactone/chemistry , Candida/enzymology , Enzymes, Immobilized/chemistry , Esterification , Fungal Proteins/chemistry , Hydrolysis , Hydroxybutyrates/chemical synthesis , Hydroxybutyrates/chemistry , Ketones/chemical synthesis , Lipase/chemistry , Models, Molecular , Stereoisomerism
17.
G3 (Bethesda) ; 8(8): 2673-2683, 2018 07 31.
Article in English | MEDLINE | ID: mdl-29907649

ABSTRACT

The heavy selection pressure due to intensive breeding of Brassica napus has created a narrow gene pool, limiting the ability to produce improved varieties through crosses between B. napus cultivars. One mechanism that has contributed to the adaptation of important agronomic traits in the allotetraploid B. napus has been chromosomal rearrangements resulting from homoeologous recombination between the constituent A and C diploid genomes. Determining the rate and distribution of such events in natural B. napus will assist efforts to understand and potentially manipulate this phenomenon. The Brassica high-density 60K SNP array, which provides genome-wide coverage for assessment of recombination events, was used to assay 254 individuals derived from 11 diverse cultivated spring type B. napus These analyses identified reciprocal allele gain and loss between the A and C genomes and allowed visualization of de novo homoeologous recombination events across the B. napus genome. The events ranged from loss/gain of 0.09 Mb to entire chromosomes, with almost 5% aneuploidy observed across all gametes. There was a bias toward sub-telomeric exchanges leading to genome homogenization at chromosome termini. The A genome replaced the C genome in 66% of events, and also featured more dominantly in gain of whole chromosomes. These analyses indicate de novo homoeologous recombination is a continuous source of variation in established Brassica napus and the rate of observed events appears to vary with genetic background. The Brassica 60K SNP array will be a useful tool in further study and manipulation of this phenomenon.


Subject(s)
Brassica napus/genetics , Polymorphism, Single Nucleotide , Recombination, Genetic , Chromosomes, Plant/genetics , Gene Frequency , Genome, Plant , Oligonucleotide Array Sequence Analysis
18.
ACS Biomater Sci Eng ; 4(10): 3522-3533, 2018 Oct 08.
Article in English | MEDLINE | ID: mdl-33465905

ABSTRACT

Engineered tissue barrier models offer in vitro alternatives in toxicology and disease research. To mimic barrier-tissue microenvironment, a porous membrane that can approach the stiffness of physiological basement membranes is required. While several biocompatible membranes with micrometer range thickness (10 µm) and a stiffness less than polystyrene (3 GPa) or polyethylene (PET, 2 GPa), have been developed, there has been little effort to optimize the process to enable rapid and reproducible pore production in these membranes. Here, we investigate the use of laser irradiation with femtosecond (fs) pulses because the combination of high-precision and cold-ablation causes minimal damage to polymeric membranes. This process enables automated, high-throughput and reproducible fabrication of thin, microporous membranes that can be utilized to culture cells at air-liquid interface (ALI), a unique culture technique that simulates the tissue-barrier microenvironment. We show the optimization of laser parameters on a thin polyurethane membrane and patterned pores with an average diameter of 5 µm. Tissue was cultured at ALI for 28 days to demonstrate the membrane's utility in constructing a tissue barrier model. These results confirm the utilization of fs laser machining as a viable method for creating a porous barrier substrate in tissue engineering platforms.

19.
JCI Insight ; 2(5): e91225, 2017 03 09.
Article in English | MEDLINE | ID: mdl-28289718

ABSTRACT

Noonan syndrome (NS; MIM 163950) is an autosomal dominant disorder and a member of a family of developmental disorders termed "RASopathies," which are caused mainly by gain-of-function mutations in genes encoding RAS/MAPK signaling pathway proteins. Whole exome sequencing (WES) and trio-based genomic triangulation of a 15-year-old female with a clinical diagnosis of NS and concomitant cardiac hypertrophy and her unaffected parents identified a de novo variant in MRAS-encoded RAS-related protein 3 as the cause of her disease. Mutation analysis using in silico mutation prediction tools and molecular dynamics simulations predicted the identified variant, p.Gly23Val-MRAS, to be damaging to normal protein function and adversely affect effector interaction regions and the GTP-binding site. Subsequent ectopic expression experiments revealed a 40-fold increase in MRAS activation for p.Gly23Val-MRAS compared with WT-MRAS. Additional biochemical assays demonstrated enhanced activation of both RAS/MAPK pathway signaling and downstream gene expression in cells expressing p.Gly23Val-MRAS. Mutational analysis of MRAS in a cohort of 109 unrelated patients with phenotype-positive/genotype-negative NS and cardiac hypertrophy yielded another patient with a sporadic de novo MRAS variant (p.Thr68Ile, c.203C>T). Herein, we describe the discovery of mutations in MRAS in patients with NS and cardiac hypertrophy, establishing MRAS as the newest NS with cardiac hypertrophy-susceptibility gene.


Subject(s)
Cardiomegaly/genetics , Genes, ras , Noonan Syndrome/genetics , Adolescent , Adult , Amino Acid Sequence , Cardiomegaly/complications , Child , Child, Preschool , Female , HEK293 Cells , Humans , Infant , Infant, Newborn , Male , Middle Aged , Molecular Dynamics Simulation , Noonan Syndrome/complications , Sequence Homology, Amino Acid , Exome Sequencing , Young Adult
20.
Theor Appl Genet ; 130(4): 621-633, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28220206

ABSTRACT

The Brassica napus 60K Illumina Infinium™ SNP array has had huge international uptake in the rapeseed community due to the revolutionary speed of acquisition and ease of analysis of this high-throughput genotyping data, particularly when coupled with the newly available reference genome sequence. However, further utilization of this valuable resource can be optimized by better understanding the promises and pitfalls of SNP arrays. We outline how best to analyze Brassica SNP marker array data for diverse applications, including linkage and association mapping, genetic diversity and genomic introgression studies. We present data on which SNPs are locus-specific in winter, semi-winter and spring B. napus germplasm pools, rather than amplifying both an A-genome and a C-genome locus or multiple loci. Common issues that arise when analyzing array data will be discussed, particularly those unique to SNP markers and how to deal with these for practical applications in Brassica breeding applications.


Subject(s)
Brassica napus/genetics , Genotype , Oligonucleotide Array Sequence Analysis , Polymorphism, Single Nucleotide , Alleles , Chromosome Mapping , Evolution, Molecular , Gene Rearrangement , Genetic Linkage , Genetic Markers , Genetics, Population , Genome, Plant , Genotyping Techniques , Plant Breeding
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