Molecular and chemical characterization of genes involved in maize cuticular wax biosynthesis

The primary surfaces of the arial parts of plants, and the surfaces of reproductive organs are covered by an extra cellular layer called the cuticle. The cuticle provides the foremost protection to the plant in order to adapt to the terrestrial environment. The cuticle composed of a biopolymer (cutin), which is embedded in a coating of cuticular waxes. Understanding the biochemical, genetic and physiological mechanisms for the biosynthesis of these cuticular waxes is relatively poor. This body of work has established methods for the chemical analysis of the cuticular waxes of maize plants. I have used these methods to chemically characterize cuticular waxes and intermediates of cuticular wax biosynthesis in mutant plants that show aberrant accumulation of these components. In addition, I have generated a yeast-based heterologous expression system for testing the biochemical and genetic properties of genes that are involved in cuticular wax biosynthesis. These accomplishments have set the stage for deciphering the complexity of cuticular wax biosynthesis

Metabolomic Profiling of the Nectars of Aquilegia pubescens and A. Canadensis

To date, variation in nectar chemistry of flowering plants has not been studied in detail. Such variation exerts considerable influence on pollinator-plant interactions, as well as on flower traits that play important roles in the selection of a plant for visitation by specific pollinators. Over the past 60 years the Aquilegia genus has been used as a key model for speciation studies. In this study, we defined the metabolomic profiles of flower samples of two Aquilegia species, A. Canadensis and A. pubescens. We identified a total of 75 metabolites that were classified into six main categories: organic acids, fatty acids, amino acids, esters, sugars, and unknowns. The mean abundances of 25 of these metabolites were significantly different between the two species, providing insights into interspecies variation in floral chemistry. Using the PlantSEED biochemistry database, we found that the majority of these metabolites are involved in biosynthetic pathways. Finally, we explored the annotated genome of A. coerulea, using the PlantSEED pipeline and reconstructed the metabolic network of Aquilegia. This network, which contains the metabolic pathways involved in generating the observed chemical variation, is now publicly available from the DOE Systems Biology Knowledge Base (KBase; http://kbase.us)

Privacy-by-Design Framework for Assessing Internet of Things Applications and Platforms

Internet of Things (IoT) systems are designed and developed either as standalone applications from the ground-up or with the help of IoT middleware platforms. They are designed to support different kinds of scenarios, such as smart homes and smart cities. Thus far, privacy concerns have not been explicitly considered by IoT ap- plications and middleware platforms. This is partly due to the lack of systematic methods for designing privacy that can guide the software development process in IoT. In this paper, we propose a set of guidelines, a privacy- by-design framework, that can be used to assess privacy capabilities and gaps of existing IoT applications as well as middleware platforms. We have evaluated two open source IoT middleware platforms, namely OpenIoT and Eclipse SmartHome, to demonstrate how our framework can be used in this way

Impact of Flow Rate, Collection Devices, and Extraction Methods on Tear Concentrations Following Oral Administration of Doxycycline in Dogs and Cats

Purpose: Compare the precision of doxycycline quantification in tear fluid collected with either Schirmer strips or polyvinyl acetal (PVA) sponges following oral drug administration. Methods: Three dogs and 3 cats were administered doxycycline orally at a dose of 4.2–5 mg/kg every 12 h for 6 consecutive days. At day 5 and 6, blood and tear fluid were sampled to capture doxycycline trough and maximal concentrations. Tear fluid was collected 3 times (spaced 10 min apart) at each session with the absorbent material placed in the lower conjunctival fornix until the 20-mm mark was reached (Schirmer strip, one eye) or for 1 min (PVA sponge, other eye). Tear extraction was performed with either centrifugation or elution in methanol. Doxycycline concentrations were measured with liquid chromatography–mass spectrometry. Low (100 ng/mL) and high (1,000 ng/mL) tear concentrations measured in vivo were spiked into each absorbent material in vitro to evaluate percentage drug recovery. Results: After oral administration of doxycycline, the drug reached the tear compartment at concentrations of 45.1–900.7 ng/mL in cats and 45.4–632.0 ng/mL in dogs, representing a tear-to-serum ratio of 12% and 16%, respectively. Doxycycline tear concentrations were significantly more precise when tear collection was performed with Schirmer strips rather than PVA sponges (P = 0.007), but were not correlated with tear flow rate. In vitro doxycycline recovery was poor to moderate (\u3c75%). Conclusions: Schirmer strips represent a good option for lacrimal doxycycline quantification, although the collection and subsequent extraction have to be optimized to improve drug recovery

A Universal Design for Success: A Mixed-methods Case Study of a First-year BScN Course

No single universal learner type exists, however historically, pedagogical practices in higher education have focused on meeting the learning needs of an average or typical student. The purpose of this study was to describe the manner and extent in which a course, designed using Universal Design for Learning (UDL) principles, provided an inclusive learning environment to a diverse population of first-year baccalaureate nursing students. Co-instructors redesigned a large in-person and place-based course using theoretical and structural principles of UDL to remove potential learning barriers and promote authentic inclusion of all students. A convergent mixed methods descriptive case study design was used to gather qualitative and quantitative data. A purposive convenience sample was drawn from a class of 223 full and part time nursing students. Qualitative data were collected through an end of semester focus group interview (n=12) and research team meetings. Quantitative data collection involved using the Inclusive Teaching Strategies Inventory-Students survey questionnaire (Gawronski, et al., 2016) at course completion (n=32), and document review of final grades (n= 206). The use of UDL principles in the design and teaching supported the needs and abilities of learners with a variety of learning preferences and experience. Students experienced a more inclusive environment with fewer barriers to learning. Large in-person and place-based post-secondary courses designed using the key tenets of UDL successfully support inclusivity of the needs of learners with diverse backgrounds, abilities, and preferences, by proactively reducing barriers in the learning environment. Résumé Il existe plusieurs types d’apprenantes, mais historiquement, les pratiques pédagogiques en formation de niveau supérieur ont été axées sur la satisfaction des besoins d’apprentissage d’une étudiante moyenne ou typique. Le but de cette étude était de décrire la manière et la mesure dans laquelle un cours, conçu selon les principes de la conception universelle pour l’apprentissage (CUA), offrait un environnement d’apprentissage inclusif à une population diversifiée d’étudiantes de première année au baccalauréat en sciences infirmières. Les co-enseignantes ont repensé un cours donné à un vaste groupe en présentiel, en utilisant les principes théoriques et structurels de la CUA pour éliminer les obstacles potentiels à l’apprentissage et promouvoir l’inclusion authentique de toutes les étudiantes. Une combinaison d’une approche mixte et d’étude de cas descriptive a été utilisée pour recueillir des données qualitatives et quantitatives. Un échantillon de convenance a été tiré d’une classe de 223 étudiantes en sciences infirmières inscrites à temps plein ou à temps partiel. Les données qualitatives ont été recueillies lors d’une entrevue de groupe en fin de semestre (n=12) et lors de réunions de l’équipe de recherche. La collecte de données quantitatives impliquait l’utilisation du questionnaire d’enquête Inclusive Teaching Strategies Inventory-Students (inventaire des stratégies inclusives d’enseignement — étudiantes; Gawronski et al., 2016) à la fin du cours (n = 32) ainsi que l’examen des documents de notes finales (n = 206). Les principes de la CUA appliqués à la conception et à l’enseignement ont soutenu les besoins et les capacités des apprenantes détenant une variété de préférences et d’expériences d’apprentissage. Les étudiantes ont connu un environnement plus inclusif avec moins d’obstacles à l’apprentissage. Les grands cours postsecondaires en présentiel conçus à l’aide des principes clés de la CUA soutiennent avec succès l’inclusion des besoins des apprenantes ayant des expériences antérieures différentes, des capacités et des préférences diverses, tout en réduisant de manière proactive les obstacles dans l’environnement d’apprentissage

A single-cell platform for reconstituting and characterizing fatty acid elongase component enzymes

Fatty acids of more than 18-carbons, generally known as very long chain fatty acids (VLCFAs) are essential for eukaryotic cell viability, and uniquely in terrestrial plants they are the precursors of the cuticular lipids that form the organism’s outer barrier to the environment. VLCFAs are synthesized by fatty acid elongase (FAE), which is an integral membrane enzyme system with multiple components. The genetic complexity of the FAE system, and its membrane association has hampered the biochemical characterization of FAE. In this study we computationally identified Zea mays genetic sequences that encode the enzymatic components of FAE and developed a heterologous expression system to evaluate their functionality. The ability of the maize components to genetically complement Saccharomyces cerevisiae lethal mutants confirmed the functionality of ZmKCS4, ZmELO1, ZmKCR1, ZmKCR2, ZmHCD and ZmECR, and the VLCFA profiles of the resulting strains were used to infer the ability of each enzyme component to determine the product profile of FAE. These characterizations indicate that the product profile of the FAE system is an attribute shared among the KCS, ELO, and KCR components of FAE

Perceptions of Facilitators and Barriers to Smoking Cessation Among Patients and Providers in a Cancer Center: A Single Institution Qualitative Exploratory Study

PURPOSE: Cancer patients who remain tobacco users have poorer outcomes, including increased mortality and decreased treatment tolerance; however, cessation post-diagnosis is challenging. Our formative research explored cessation-related perspectives among patients and staff at one National Cancer Institute-designated cancer center, to inform improving cessation services within oncology care. METHODS: Using a descriptive phenomenological approach, a purposive sample of current cancer patients (n = 13) and cancer center physicians and cessation program staff (n = 9) were recruited to complete one-on-one audio-recorded in-depth qualitative interviews, to explore experiences providing or receiving cessation support, and perspectives on patients\u27 readiness and needs regarding cessation. Thematic coding utilized Green\u27s predisposing, enabling, and reinforcing framework to identify factors having positive, negative, or mixed impact on delivery of best-practices cessation services (ie, 5As) and patient cessation success. RESULTS: Patients identified cancer diagnosis as a wake-up call, existing health problems, persistent healthcare providers, cost of cigarettes, and societal disapproval of smoking as factors facilitating quitting. Futility of quitting after a cancer diagnosis, cost and logistics of program participation, clinician time constraints, and lifetime addiction made quitting harder. Family, friends, stigma and motivation, and pharmacotherapies played mixed roles. Patients felt survivor-focused cessation programs, including stress management, could better enable quitting. Provider-anticipated problems with implementing cessation counseling included so-called therapeutic nihilism (ie, pessimism regarding cessation post-diagnosis), lack of training and standardized approaches, and time and documentation burden. Clinicians saw both policies and peer clinician champions as potentially increasing prioritization of cessation within oncology. CONCLUSIONS: Findings highlight unmet needs for patients and providers regarding provision of effective cessation care. Despite survival benefit, cessation is still not standard within cancer care. Our results show that many patients would benefit from standardized programs where they are routinely asked about cessation. Providers would benefit from both structural enhancements and professional education to ensure that evidence-based cessation services tailored to cancer patients, are offered throughout treatment and survivorship

Developmental Changes in the Metabolic Network of Snapdragon Flowers

Evolutionary and reproductive success of angiosperms, the most diverse group of land plants, relies on visual and olfactory cues for pollinator attraction. Previous work has focused on elucidating the developmental regulation of pathways leading to the formation of pollinator-attracting secondary metabolites such as scent compounds and flower pigments. However, to date little is known about how flowers control their entire metabolic network to achieve the highly regulated production of metabolites attracting pollinators. Integrative analysis of transcripts and metabolites in snapdragon sepals and petals over flower development performed in this study revealed a profound developmental remodeling of gene expression and metabolite profiles in petals, but not in sepals. Genes up-regulated during petal development were enriched in functions related to secondary metabolism, fatty acid catabolism, and amino acid transport, whereas down-regulated genes were enriched in processes involved in cell growth, cell wall formation, and fatty acid biosynthesis. The levels of transcripts and metabolites in pathways leading to scent formation were coordinately up-regulated during petal development, implying transcriptional induction of metabolic pathways preceding scent formation. Developmental gene expression patterns in the pathways involved in scent production were different from those of glycolysis and the pentose phosphate pathway, highlighting distinct developmental regulation of secondary metabolism and primary metabolic pathways feeding into it

Metabolic, inflammatory and haemostatic effects of a low-dose continuous combined HRT in women with type 2 diabetes: potentially safer with respect to vascular risk?

BACKGROUND Conventional hormone replacement therapy (HRT) containing conjugated equine oestrogen (CEE) and medroxyprogesterone acetate (MPA) increases triglyceride, C- reactive protein (CRP) and coagulation Factor VII concentrations, potentially explaining their increased coronary heart disease (CHD) and stroke risk. OBJECTIVE To assess the metabolic effects of a continuous combined HRT containing 1 mg oestradiol and 0.5 mg norethisterone or matching placebo. DESIGN Double-blind, randomized placebo-controlled trial. PATIENTS Fifty women with type 2 diabetes. MEASUREMENTS Classical and novel risk factors for vascular disease. RESULTS Triglyceride concentration was not altered (P = 0.31, change in active arm relative to placebo) and low-density lipoprotein (LDL) cholesterol concentration declined 13% (P = 0.018). IL-6 concentration (mean difference -1.42 pg/ml, 95% CI: -2.55 to - 0.29 IU/dl, P = 0.015), Factor VII (-32 IU/dl, -43 to -21 IU/l, P lt 0.001) and tissue plasminogen activator antigen (by 13%, P = 0.005) concentrations fell, but CRP was not significantly altered (P = 0.62). Fasting glucose (P = 0.026) also declined significantly, but there are no significant effects on HBA1c, Factor IX or APC resistance. CONCLUSIONS HRT containing 1 mg oestradiol and 0.5 mg norethisterone may avoid the adverse metabolic effects potentially implicated in the elevated CHD and stroke risk induced by conventional higher dose HRT. This type of preparation may therefore be more suitable than conventional HRT for women at elevated CHD risk such as those with type 2 diabetes. Large randomized controlled trials of such low dose preparations, powered for cardiovascular end points, are now needed