352 research outputs found

    Trichome Development in \u3ci\u3eArabidopsis thaliana\u3c/i\u3e. II. lsolation and Complementation of the \u3ci\u3eGLABROUS1\u3c/i\u3e Gene

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    We are using the formation of trichomes in Arabidopsis thaliana as a model system to study gene expression during cellular differentiation. To initiate the molecular characterization of this system, we tagged and isolated a gene that is specifically required for the development of the specialized trichome cell. We confirmed the identity of this gene, GLABROUS1 (GL1), by complementation. These results demonstrate that a crucial gene in a plant developmental pathway can be successfully identified by complementation

    Development of a System for Directed Evolution of \u3cem\u3eArabidopsis\u3c/em\u3e Formate Dehydrogenase to Utilize NADP as a Cofactor

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    Formate dehydrogenase (FDH) is a NAD-dependent enzyme found in methylotrophic bacteria, yeast and plants. This enzyme catalyzes the reversible oxidation of formate to carbon dioxide. The goal of this research was to determine the feasibility of using a directed evolution approach to generate an altered Arabidopsis FDH with a high affinity for NADP as a cofactor. A PCR procedure that induced approximately 1.5 mutations in the wild-type Arabidopsis FDH sequence per thousand base pairs was developed and the amplified products were transformed into E. coli cells. Approximately 1300 cell lines were assayed in 96-well microplates for activity with NADP+ and 100 putative mutants were selected for further study. One particular mutant line, pFDH-18, possessed reproducible NADP+-FDH activity. Sequence analysis showed that a single T in the wild-type DNA sequence had been changed to a G. The result of this mutation was that an isoleucine (Ile) residue at position 188 in the wild-type enzyme was converted to a methionine. This particular Ile residue is conserved in the known FDH sequences from higher plants and is located in the region of the enzyme that contains the binding domain for the NAD cofactor

    Psychometric Evaluation of a Coping Strategies Inventory Short-Form (CSI-SF) in the Jackson Heart Study Cohort

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    This study sought to establish the psychometric properties of a Coping Strategies Inventory Short Form (CSISF) by examining coping skills in the Jackson Heart Study cohort. We used exploratory and confirmatory factor analysis, Pearson’s correlation, and Cronbach Alpha to examine reliability and validity in the CSI-SF that solicited responses from 5302 African American men and women between the ages of 35 and 84. One item was dropped from the 16-item CSI-SF, making it a 15-item survey. No significant effects were found for age and gender, strengthening the generalizability of the CSI-SF. The internal consistency reliability analysis revealed reliability between alpha = 0.58-0.72 for all of the scales, and all of the fit indices used to examine the CSI-SF provided support for its use as an adequate measure of coping. This study provides empirical support for utilizing this instrument in future efforts to understand the role of coping in moderating health outcomes

    Dicamba Resistance: Enlarging and Preserving Biotechnology-Based Weed Management Strategies

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    The advent of biotechnology-derived, herbicide-resistant crops has revolutionized farming practices in many countries. Facile, highly effective, environmentally sound, and profitable weed control methods have been rapidly adopted by crop producers who value the benefits associated with biotechnology-derived weed management traits. But a rapid rise in the populations of several troublesome weeds that are tolerant or resistant to herbicides currently used in conjunction with herbicide-resistant crops may signify that the useful lifetime of these economically important weed management traits will be cut short. We describe the development of soybean and other broadleaf plant species resistant to dicamba, a widely used, inexpensive, and environmentally safe herbicide. The dicamba resistance technology will augment current herbicide resistance technologies and extend their effective lifetime. Attributes of both nuclear- and chloroplast- encoded dicamba resistance genes that affect the potency and expected durability of the herbicide resistance trait are examined

    Dicamba Resistance: Enlarging and Preserving Biotechnology-Based Weed Management Strategies

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    The advent of biotechnology-derived, herbicide-resistant crops has revolutionized farming practices in many countries. Facile, highly effective, environmentally sound, and profitable weed control methods have been rapidly adopted by crop producers who value the benefits associated with biotechnology-derived weed management traits. But a rapid rise in the populations of several troublesome weeds that are tolerant or resistant to herbicides currently used in conjunction with herbicide-resistant crops may signify that the useful lifetime of these economically important weed management traits will be cut short. We describe the development of soybean and other broadleaf plant species resistant to dicamba, a widely used, inexpensive, and environmentally safe herbicide. The dicamba resistance technology will augment current herbicide resistance technologies and extend their effective lifetime. Attributes of both nuclear- and chloroplast- encoded dicamba resistance genes that affect the potency and expected durability of the herbicide resistance trait are examined

    Illness perception and related behaviour in lower respiratory tract infections—a European study

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    Background. Lower respiratory tract infection (LRTI) is a common presentation in primary care, but little is known about associated patients’ illness perception and related behaviour. Objective. To describe illness perceptions and related behaviour in patients with LRTI visiting their general practitioner (GP) and identify differences between European regions and types of health care system. Methods. Adult patients presenting with acute cough were included. GPs recorded co morbidities and clinical findings. Patients filled out a diary for up to 4 weeks on their symptoms, illness perception and related behaviour. The chi-square test was used to compare proportions between groups and the Mann-Whitney U or Kruskal Wallis tests were used to compare means. Results. Three thousand one hundred six patients from 12 European countries were included. Eighty-one per cent (n = 2530) of the patients completed the diary. Patients were feeling unwell for a mean of 9 (SD 8) days prior to consulting. More than half experienced impairment of normal or social activities for at least 1 week and were absent from work/school for a mean of 4 (SD 5) days. On average patients felt recovered 2 weeks after visiting their GP, but 21% (n = 539) of the patients did not feel recovered after 4 weeks. Twenty-seven per cent (n = 691) reported feeling anxious or depressed, and 28% (n = 702) re-consulted their GP at some point during the illness episode. Reported illness duration and days absent from work/school differed between countries and regions (North-West versus South-East), but there was little difference in reported illness course and related behaviour between health care systems (direct access versus gate-keeping). Conclusion. Illness course, perception and related behaviour in LRTI differ considerably between countries. These finding should be taken into account when developing International guidelines for LRTI and interventions for setting realistic expectations about illness course

    Overfishing Drives Over One-Third of All Sharks and Rays Toward a Global Extinction Crisis

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    The scale and drivers of marine biodiversity loss are being revealed by the International Union for Conservation of Nature (IUCN) Red List assessment process. We present the first global reassessment of 1,199 species in Class Chondrichthyes-sharks, rays, and chimeras. The first global assessment (in 2014) concluded that one-quarter (24%) of species were threatened. Now, 391 (32.6%) species are threatened with extinction. When this percentage of threat is applied to Data Deficient species, more than one-third (37.5%) of chondrichthyans are estimated to be threatened, with much of this change resulting from new information. Three species are Critically Endangered (Possibly Extinct), representing possibly the first global marine fish extinctions due to overfishing. Consequently, the chondrichthyan extinction rate is potentially 25 extinctions per million species years, comparable to that of terrestrial vertebrates. Overfishing is the universal threat affecting all 391 threatened species and is the sole threat for 67.3% of species and interacts with three other threats for the remaining third: loss and degradation of habitat (31.2% of threatened species), climate change (10.2%), and pollution (6.9%). Species are disproportionately threatened in tropical and subtropical coastal waters. Science-based limits on fishing, effective marine protected areas, and approaches that reduce or eliminate fishing mortality are urgently needed to minimize mortality of threatened species and ensure sustainable catch and trade of others. Immediate action is essential to prevent further extinctions and protect the potential for food security and ecosystem functions provided by this iconic lineage of predators

    National Outbreak of Salmonella Serotype Saintpaul Infections: Importance of Texas Restaurant Investigations in Implicating Jalapeño Peppers

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    BACKGROUND: In May 2008, PulseNet detected a multistate outbreak of Salmonella enterica serotype Saintpaul infections. Initial investigations identified an epidemiologic association between illness and consumption of raw tomatoes, yet cases continued. In mid-June, we investigated two clusters of outbreak strain infections in Texas among patrons of Restaurant A and two establishments of Restaurant Chain B to determine the outbreak's source. METHODOLOGY/PRINCIPAL FINDINGS: We conducted independent case-control studies of Restaurant A and B patrons. Patients were matched to well controls by meal date. We conducted restaurant environmental investigations and traced the origin of implicated products. Forty-seven case-patients and 40 controls were enrolled in the Restaurant A study. Thirty case-patients and 31 controls were enrolled in the Restaurant Chain B study. In both studies, illness was independently associated with only one menu item, fresh salsa (Restaurant A: matched odds ratio [mOR], 37; 95% confidence interval [CI], 7.2-386; Restaurant B: mOR, 13; 95% CI 1.3-infinity). The only ingredient in common between the two salsas was raw jalapeño peppers. Cultures of jalapeño peppers collected from an importer that supplied Restaurant Chain B and serrano peppers and irrigation water from a Mexican farm that supplied that importer with jalapeño and serrano peppers grew the outbreak strain. CONCLUSIONS/SIGNIFICANCE: Jalapeño peppers, contaminated before arrival at the restaurants and served in uncooked fresh salsas, were the source of these infections. Our investigations, critical in understanding the broader multistate outbreak, exemplify an effective approach to investigating large foodborne outbreaks. Additional measures are needed to reduce produce contamination
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