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1.
Rev Sci Instrum ; 93(10): 103306, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319318

RESUMO

Scintillators are vital components for nuclear instrumentation and its applications, including plasma diagnostics and imaging. As yields in controlled fusion experiments increase, the radiation tolerance of scintillator candidates for use in instrumentation is of particular importance. High radiation exposure can damage scintillating materials and alter the optical properties. The effects of radiation damage in Ce-doped mixed garnet ceramics over the compositional range (Y,Gd,Lu)3(Al,Ga)5O12 are investigated using optical techniques. The samples were exposed to 200 keV protons to an accumulated fluence of 1016 protons per square centimeter, then characterized using diffuse reflectance spectroscopy (DRS). DRS with visible light can assess the radiation tolerance of opaque poly-crystalline samples, which can be easily sintered from powders and thus offer distinct advantages in characterization compared to single crystals. Qualitative trends in induced absorption are presented as a function of composition, and the ideal cerium dopant concentration for Y2LuAl5O12 is determined to be 0.60-0.75 mol. %.

2.
Transl Behav Med ; 11(5): 1127-1141, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-33677571

RESUMO

Previous reviews have established that workplace wellbeing initiatives are effective at promoting wellbeing, but less is known about which intervention characteristics or "active ingredients" underpin this effectiveness (i.e., behavior change techniques [BCTs]). This review aims to illuminate the connections between the types of BCTs and the level of intervention intensity with intervention effectiveness. A systematic search for peer-reviewed studies evaluating a workplace wellbeing initiative was undertaken across five databases: Medline, Scopus, PsycInfo, and CINAHL (Ovid Emcare). Eligible studies included those that evaluated the effect of a workplace wellbeing initiative on participants' physical wellbeing (e.g., physical activity and quality of life) and psychological wellbeing (e.g., mental health and stress), were published between 2009 and September 2019, and utilized a comparator (e.g., control group or prepost change). Studies were screened in independent duplicate to minimize bias. Effect sizes were calculated. Following removal of duplicates, 1,541 studies were identified and screened for eligibility. Of these, 23 studies reporting 28 comparisons were deemed to meet eligibility criteria. Just over 50% of these studies reported evidence of either a strong or moderate effect across a physical and a psychological outcome, providing a positive indication that workplace wellbeing programs can promote physical and psychological wellbeing in workers. Interventions tended to employ multiple BCTs (mean range 8.1-9.4), however, no discernible patterns between the types or numbers of BCTs employed and intervention effectiveness was found. Further experimental work is required that compares and contrasts workplace wellbeing initiatives to enable a better understanding of how to develop and implement highly effective programs.


Assuntos
Qualidade de Vida , Local de Trabalho , Terapia Comportamental , Exercício Físico , Humanos , Saúde Mental
3.
PLoS One ; 13(8): e0202921, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30138445

RESUMO

Hybrid crops produce higher yields than their inbred parents due to heterosis. For high purity of hybrid seeds, it is critical to eliminate self-pollination. Manual or mechanical removal of male parts (such as detasseling in maize) is labor-intensive, fuel and time-consuming, and can cause physical damage to female plants, resulting in significant seed yield reductions. Many male-sterility systems either require a maintainer for male-sterile line propagation or are often affected by environmental factors. Roundup® Hybridization System (RHS) utilizes glyphosate to induce male sterility, which effectively eliminates the need for maintainer lines and removal of male parts for commercial hybrid seed production. The first-generation RHS (RHS1) is based on low expression of a glyphosate-insensitive 5-enolpyruvylshikimate-3-phosphate synthase (CP4 EPSPS) in pollen. This report presents the second-generation RHS (RHS2) technology built on RNA interference (RNAi) combined with CP4 EPSPS. It utilizes maize endogenous male tissue-specific small interfering RNAs (mts-siRNAs) to trigger cleavage of the CP4 EPSPS mRNA specifically in tassels, resulting in glyphosate-sensitive male cells due to lack of the CP4 EPSPS protein. Male sterility is then induced by glyphosate application at the stages critical for pollen development, and the male-sterile plants are used as the female parent to produce hybrid seed. The endogenous mts-siRNAs are conserved across maize germplasms, and the inducible male sterility was replicated in representative germplasms through introgression of a CP4 EPSPS transgene containing the mts-siRNA target sequence. This technology combines the relative simplicity and convenience of a systemic herbicide spray methodology with targeted protein expression to create an inducible male sterility system for industrial production of row crop hybrid seeds in an environmentally-independent manner.


Assuntos
Produtos Agrícolas/genética , Hibridização Genética , Zea mays/genética , Produtos Agrícolas/fisiologia , Engenharia Genética/métodos , Glicina/análogos & derivados , Glicina/metabolismo , Pólen/metabolismo , Interferência de RNA , Sementes/genética , Sementes/fisiologia , Zea mays/fisiologia , Glifosato
4.
J Cancer Surviv ; 11(4): 486-497, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28374090

RESUMO

PURPOSE: This systematic narrative review describes and compares the development and operational approaches of monitoring systems without a clinical care component that collect patient-reported outcome (PRO) data from cancer survivors. METHODS: Searches were conducted using Medline, PubMed, PsycINFO, the Cochrane Library, CINAHL, Scopus, Joanna Briggs Institute EBP Database and Google Scholar (Advanced). Sources of grey literature and websites of relevant organisations were also searched for relevant published and unpublished material. Articles were included if they described the development (including piloting) of monitoring systems with ongoing recruitment that collect PRO at more than one time point, from 6 months post-diagnosis onward. RESULTS: The initial searches returned 7290 unique citations. After screening titles and abstracts, 39 full-text articles were retrieved for more detailed examination. Eleven articles were included in the review, representing seven international monitoring systems. Systems varied in their scope, implementation process, governance and administration, recruitment and data collection, consent rates, PRO collection, use of PRO and translation strategies. CONCLUSIONS: The most suitable approach for setting-up and implementing a monitoring system for ongoing surveillance will differ depending on the unique requirements, aims and level of resourcing available within a particular context. Better specification and consideration of how PRO data will be used, for what purpose, and by whom, is required to inform effective translational strategies to improve outcomes for cancer survivors. IMPLICATIONS FOR CANCER SURVIVORS: The findings from this review may inform the future development of survivorship monitoring systems in varied environments, which in turn may improve practices that lead to better outcomes for survivors.


Assuntos
Neoplasias/mortalidade , Medidas de Resultados Relatados pelo Paciente , Sobreviventes/psicologia , Humanos , Taxa de Sobrevida
5.
Rev Sci Instrum ; 86(8): 083303, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26329177

RESUMO

A method for achieving good position resolution of low-intensity electron signals using a microchannel plate resistive anode detector is demonstrated. Electron events at a rate of 7 counts s(-1) are detected using a Z-stack microchannel plate. The dependence of position resolution on both the distance and the potential difference between the microchannel plate and resistive anode is investigated. Using standard commercial electronics, a measured position resolution of 170 µm (FWHM) is obtained, which corresponds to an intrinsic resolution of 157 µm (FWHM).

6.
RNA ; 21(5): 840-50, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25802407

RESUMO

Environmental RNAi (eRNAi) is a sequence-specific regulation of endogenous gene expression in a receptive organism by exogenous double-stranded RNA (dsRNA). Although demonstrated under artificial dietary conditions and via transgenic plant presentations in several herbivorous insects, the magnitude and consequence of exogenous dsRNA uptake and the role of eRNAi remains unknown under natural insect living conditions. Our analysis of coleopteran insects sensitive to eRNAi fed on wild-type plants revealed uptake of plant endogenous long dsRNAs, but not small RNAs. Subsequently, the dsRNAs were processed into 21 nt siRNAs by insects and accumulated in high quantities in insect cells. No accumulation of host plant-derived siRNAs was observed in lepidopteran larvae that are recalcitrant to eRNAi. Stability of ingested dsRNA in coleopteran larval gut followed by uptake and transport from the gut to distal tissues appeared to be enabling factors for eRNAi. Although a relatively large number of distinct coleopteran insect-processed plant-derived siRNAs had sequence complementarity to insect transcripts, the vast majority of the siRNAs were present in relatively low abundance, and RNA-seq analysis did not detect a significant effect of plant-derived siRNAs on insect transcriptome. In summary, we observed a broad genome-wide uptake of plant endogenous dsRNA and subsequent processing of ingested dsRNA into 21 nt siRNAs in eRNAi-sensitive insects under natural feeding conditions. In addition to dsRNA stability in gut lumen and uptake, dosage of siRNAs targeting a given insect transcript is likely an important factor in order to achieve measurable eRNAi-based regulation in eRNAi-competent insects that lack an apparent silencing amplification mechanism.


Assuntos
Interação Gene-Ambiente , Herbivoria/genética , Insetos/genética , Interferência de RNA , Animais , Meio Ambiente , Insetos/metabolismo , Larva , Raízes de Plantas/parasitologia , RNA de Cadeia Dupla/metabolismo , RNA Interferente Pequeno/genética , Transcriptoma , Zea mays/parasitologia
7.
Transgenic Res ; 22(6): 1207-22, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23748931

RESUMO

The sequence specificity of the endogenous RNA interference pathway allows targeted suppression of genes essential for insect survival and enables the development of durable and efficacious insecticidal products having a low likelihood to adversely impact non-target organisms. The spectrum of insecticidal activity of a 240 nucleotide (nt) dsRNA targeting the Snf7 ortholog in Western Corn Rootworm (WCR; Diabrotica virgifera virgifera) was characterized by selecting and testing insects based upon their phylogenetic relatedness to WCR. Insect species, representing 10 families and 4 Orders, were evaluated in subchronic or chronic diet bioassays that measured potential lethal and sublethal effects. When a specific species could not be tested in diet bioassays, the ortholog to the WCR Snf7 gene (DvSnf7) was cloned and corresponding dsRNAs were tested against WCR and Colorado potato beetle (Leptinotarsa decemlineata); model systems known to be sensitive to ingested dsRNA. Bioassay results demonstrate that the spectrum of activity for DvSnf7 is narrow and activity is only evident in a subset of beetles within the Galerucinae subfamily of Chrysomelidae (>90% identity with WCR Snf7 240 nt). This approach allowed for evaluating the relationship between minimum shared nt sequence length and activity. A shared sequence length of ≥ 21 nt was required for efficacy against WCR (containing 221 potential 21-nt matches) and all active orthologs contained at least three 21 nt matches. These results also suggest that WCR resistance to DvSnf7 dsRNA due to single nucleotide polymorphisms in the target sequence of 240 nt is highly unlikely.


Assuntos
Controle de Insetos/métodos , Proteínas de Insetos/antagonistas & inibidores , Plantas Geneticamente Modificadas/genética , RNA de Cadeia Dupla/genética , Animais , Besouros/efeitos dos fármacos , Besouros/genética , Besouros/patogenicidade , Endotoxinas/antagonistas & inibidores , Endotoxinas/genética , Proteínas de Insetos/genética , Larva/genética , Interferência de RNA , RNA de Cadeia Dupla/farmacologia , Zea mays/genética
8.
GM Crops Food ; 4(2): 90-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23787988

RESUMO

Long double-stranded RNAs (long dsRNAs) are precursors for the effector molecules of sequence-specific RNA-based gene silencing in eukaryotes. Plant cells can contain numerous endogenous long dsRNAs. This study demonstrates that such endogenous long dsRNAs in plants have sequence complementarity to human genes. Many of these complementary long dsRNAs have perfect sequence complementarity of at least 21 nucleotides to human genes; enough complementarity to potentially trigger gene silencing in targeted human cells if delivered in functional form. However, the number and diversity of long dsRNA molecules in plant tissue from crops such as lettuce, tomato, corn, soy and rice with complementarity to human genes that have a long history of safe consumption supports a conclusion that long dsRNAs do not present a significant dietary risk.


Assuntos
Produtos Agrícolas/genética , Perfilação da Expressão Gênica , Genes de Plantas , RNA de Cadeia Dupla/genética , Análise de Sequência de RNA , Transcriptoma , Sequência de Bases , Produtos Agrícolas/normas , Humanos , Lactuca/genética , Solanum lycopersicum/genética , Oryza/genética , Interferência de RNA , Alinhamento de Sequência , Glycine max/genética
9.
BMC Genomics ; 13: 381, 2012 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-22873950

RESUMO

BACKGROUND: Plants contain significant quantities of small RNAs (sRNAs) derived from various sRNA biogenesis pathways. Many of these sRNAs play regulatory roles in plants. Previous analysis revealed that numerous sRNAs in corn, rice and soybean seeds have high sequence similarity to animal genes. However, exogenous RNA is considered to be unstable within the gastrointestinal tract of many animals, thus limiting potential for any adverse effects from consumption of dietary RNA. A recent paper reported that putative plant miRNAs were detected in animal plasma and serum, presumably acquired through ingestion, and may have a functional impact in the consuming organisms. RESULTS: To address the question of how common this phenomenon could be, we searched for plant miRNAs sequences in public sRNA datasets from various tissues of mammals, chicken and insects. Our analyses revealed that plant miRNAs were present in the animal sRNA datasets, and significantly miR168 was extremely over-represented. Furthermore, all or nearly all (>96%) miR168 sequences were monocot derived for most datasets, including datasets for two insects reared on dicot plants in their respective experiments. To investigate if plant-derived miRNAs, including miR168, could accumulate and move systemically in insects, we conducted insect feeding studies for three insects including corn rootworm, which has been shown to be responsive to plant-produced long double-stranded RNAs. CONCLUSIONS: Our analyses suggest that the observed plant miRNAs in animal sRNA datasets can originate in the process of sequencing, and that accumulation of plant miRNAs via dietary exposure is not universal in animals.


Assuntos
MicroRNAs/genética , RNA de Plantas/genética , Animais , Northern Blotting , Bombyx/genética , RNA/genética , RNA/metabolismo
10.
Plant Signal Behav ; 7(9): 1188-93, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22899065

RESUMO

The role of non-coding RNAs (ncRNAs), both short and long ncRNAs, in the regulation of gene expression has become evident in recent years. Non-coding RNA-based regulation is achieved through a variety of mechanisms; some are relatively well-characterized, while others are much less understood. MicroRNAs (miRNAs), a class of endogenous small RNAs, function as master regulators of gene expression in eukaryotic organisms. A notable, recently discovered role for long ncRNAs is that of miRNA decoys, also referred to as target mimics or sponges, in which long ncRNAs carry a short stretch of sequence sharing homology to miRNA-binding sites in endogenous targets. As a consequence, miRNA decoys are able to sequester and inactivate miRNA function. Engineered miRNA decoys are also efficacious and useful tools for studying gene function. We recently demonstrated that the potential of miRNA decoys to inactivate miRNAs in the model plants Arabidopsis thaliana and Nicotiana benthamiana is dependent on the level of sequence complementarity to miRNAs of interest. The flexibility of the miRNA decoy approach in sequence-dependent miRNA inactivation, backbone choice, ability to simultaneously inactivate multiple miRNAs, and more importantly, to achieve a desirable level of miRNA inactivation, makes it a potentially useful tool for crop improvement. This research addendum reports the functional extension of miRNA decoys from model plants to crops. Furthermore, endogenous miRNA decoys, first described in plants, have been proposed to play a significant role in regulating the transcriptome in eukaryotes. Using computational analysis, we have identified numerous endogenous sequences with potential miRNA decoy activity for conserved miRNAs in several plant species. Our data suggest that endogenous miRNA decoys can be widespread in plants and may be a component of the global gene expression regulatory network in plants.


Assuntos
Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , MicroRNAs , Nicotiana/genética , RNA de Plantas , RNA não Traduzido , Sítios de Ligação , Produtos Agrícolas/genética , Engenharia Genética , Homologia de Sequência , Transcriptoma
11.
PLoS One ; 6(6): e21330, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21731706

RESUMO

Eukaryotic organisms possess a complex RNA-directed gene expression regulatory network allowing the production of unique gene expression patterns. A recent addition to the repertoire of RNA-based gene regulation is miRNA target decoys, endogenous RNA that can negatively regulate miRNA activity. miRNA decoys have been shown to be a valuable tool for understanding the function of several miRNA families in plants and invertebrates. Engineering and precise manipulation of an endogenous RNA regulatory network through modification of miRNA activity also affords a significant opportunity to achieve a desired outcome of enhanced plant development or response to environmental stresses. Here we report that expression of miRNA decoys as single or heteromeric non-cleavable microRNA (miRNA) sites embedded in either non-protein-coding or within the 3' untranslated region of protein-coding transcripts can regulate the expression of one or more miRNA targets. By altering the sequence of the miRNA decoy sites, we were able to attenuate miRNA inactivation, which allowed for fine regulation of native miRNA targets and the production of a desirable range of plant phenotypes. Thus, our results demonstrate miRNA decoys are a flexible and robust tool, not only for studying miRNA function, but also for targeted engineering of gene expression in plants. Computational analysis of the Arabidopsis transcriptome revealed a number of potential miRNA decoys, suggesting that endogenous decoys may have an important role in natural modulation of expression in plants.


Assuntos
Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Inativação Gênica , MicroRNAs/genética , Composição de Bases/genética , Sequência de Bases , Biologia Computacional , MicroRNAs/metabolismo , Dados de Sequência Molecular , Fenótipo , Plantas Geneticamente Modificadas , RNA de Plantas/genética
12.
Epidemiol Infect ; 139(8): 1181-90, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20943002

RESUMO

Mathematical models of influenza pandemics are sensitive to changes in contact rates between individuals. We conducted population-based telephone surveys in four North Carolina counties to determine the number of social interactions between individuals during the 2007-2008 influenza season. Influenza activity was monitored through sentinel medical practices. Among 3845 adults, the number of social contacts varied with age, was lower on weekends than on weekdays, and further decreased during school holiday periods. Adults with influenza-like illnesses had fewer social contacts. Adults' contacts in the community setting increased during periods of peak influenza activity. Among 290 children, potential contacts (i.e. other people in the same location) were lowest among preschool-age children and decreased on weekends and during school holidays. In adjusted analyses, children's potential social contacts did not change during periods of peak influenza activity. These results should be useful for modelling influenza epidemics and pandemics and in planning mitigation and response strategies.


Assuntos
Influenza Humana/epidemiologia , Comportamento Social , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Influenza Humana/transmissão , Entrevistas como Assunto , Pessoa de Meia-Idade , Modelos Estatísticos , North Carolina/epidemiologia , Adulto Jovem
13.
Plant Physiol ; 153(2): 882-91, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20424004

RESUMO

We demonstrate that the transformation of soybean (Glycine max) with sense suppression constructs using intron sequences from the fatty acid oleyl Delta12 desaturase gene FAD2-1A leads to efficient and specific reduction of FAD2-1 transcripts in developing seeds, increased oleic acid, and decreased polyunsaturated fatty acids. The related FAD2-2 transcripts are only marginally affected. Despite screening a large number of independent transformants, no single-copy efficacious transformants could be found. Invariably, all the least complex transgenic loci have two T-DNA copies in an inverted repeat configuration, centered at the right borders. We show that this T-DNA configuration produces an inverted repeat transcript and that small interfering RNAs accumulate against the target sequence.


Assuntos
Ácidos Graxos Dessaturases/genética , Inativação Gênica , Glycine max/genética , Proteínas de Plantas/genética , RNA de Cadeia Dupla/genética , DNA Bacteriano/genética , DNA de Plantas/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Íntrons , Mutagênese Insercional , Plantas Geneticamente Modificadas/genética , RNA de Plantas/genética , RNA Interferente Pequeno/genética , Sementes/crescimento & desenvolvimento , Glycine max/enzimologia , Transformação Genética
14.
Phytopathology ; 96(5): 453-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-18944304

RESUMO

ABSTRACT A new variety of Nicotiana, N. edwardsonii var. Columbia, was evaluated for its capacity to serve as a new source for virus resistance genes. Columbia was developed from a hybridization between N. glutinosa and N. clevelandii, the same parents used for the formation of the original N. edwardsonii. However, in contrast to the original N. edwardsonii, crosses between Columbia and either of its parents are fertile. Thus, the inheritance of virus resistance genes present in N. glutinosa could be characterized by using Columbia as a bridge plant in crosses with the susceptible parent, N. clevelandii. To determine how virus resistance genes would segregate in interspecific crosses between Columbia and N. clevelandii, we followed the fate of the N gene, a single dominant gene that specifies resistance to Tobacco mosaic virus (TMV). Our genetic evidence indicated that the entire chromosome containing the N gene was introgressed into N. clevelandii to create an addition line, designated N. clevelandii line 19. Although line 19 was homozygous for resistance to TMV, it remained susceptible to Tomato bushy stunt virus (TBSV) and Cauliflower mosaic virus (CaMV) strain W260, indicating that resistance to these viruses must reside on other N. glutinosa chromosomes. We also developed a second addition line, N. clevelandii line 36, which was homozygous for resistance to TBSV. Line 36 was susceptible to TMV and CaMV strain W260, but was resistant to other tombusviruses, including Cucumber necrosis virus, Cymbidium ringspot virus, Lettuce necrotic stunt virus, and Carnation Italian ringspot virus.

15.
Phytopathology ; 95(2): 178-85, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18943988

RESUMO

ABSTRACT A 2-year field trial was conducted to determine the effects of green manures and crop sequences on potato scab and Verticillium wilt. In addition, indigenous streptomycete densities and in vitro pathogen inhibitory activity were measured and their relationships to plant disease were determined. Green manures (buckwheat, canola, or fallow controls) were tested in conjunction with three crop sequences (alfalfa-potato, cornpotato, and potato-potato). Compared with fallow controls, tubers grown in buckwheat-treated soil had significantly lower Verticillium wilt ratings, and tubers grown in buckwheat- or canola-treated soil had greater yields. Potatoes grown in soil planted to corn or alfalfa the previous year had significantly lower Verticillium wilt and potato scab ratings as well as higher yields than potatoes grown in soil previously planted to potato. Streptomycetes from soils collected from green manure-treated plots tended to have greater in vitro pathogen inhibitory activity than streptomycetes from fallow-treated plots. Furthermore, streptomycete pathogen inhibitory activity was frequently negatively correlated with plant disease and positively correlated with potato yield. These results indicate that green manure treatments may contribute to active management of the pathogen inhibitory activity of the streptomycete community to achieve plant disease control.

16.
Mol Plant Microbe Interact ; 17(9): 976-85, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15384488

RESUMO

A new variety of Nicotiana edwardsonii, designated N. edwardsonii cv. Columbia, expresses pathogenesis-related (PR) proteins in a temporal manner 45 to 49 days postplanting and also exhibits enhanced resistance to Tobacco mosaic virus, Tobacco necrosis virus, and Tomato bushy stunt virus. In contrast, PR proteins were not expressed in the original N. edwardsonii variety at comparable ages but were induced after onset of a hypersensitive response to viral infection. The temporal induction of PR proteins in 'Columbia' was correlated with increases in salicylic acid and glycosylated salicylic acid. Earlier studies noted that some Nicotiana hybrids derived from interspecific crosses constitutively express PR proteins, but the genetic basis of this phenomenon had not been investigated, likely because many interspecific Nicotiana crosses are sterile. However, the close genetic relationship between N. edwardsonii and 'Columbia' indicated that a hybrid between these two plants might be fertile, and this proved to be true. Genetic crosses between 'Columbia' and N. edwardsonii demonstrated that a single, dominant gene conditioned temporal expression of PR proteins and enhanced resistance. This gene was designated TPR1 (for temporal expression of PR proteins).


Assuntos
Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Nicotiana/genética , Doenças das Plantas/virologia , Vírus do Mosaico do Tabaco/patogenicidade , Tobamovirus/patogenicidade , Imunidade Inata/genética , Folhas de Planta/virologia , Nicotiana/virologia
18.
Ann Pharmacother ; 35(4): 440-51, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11302409

RESUMO

OBJECTIVE: To renew the pharmacology, pharmacokinetics, efficacy adverse events, and cost of argatroban in the prevention and treatment of thromboembolism in patients with heparin-induced thrombocytopenia (HIT). DATA SOURCES: A MEDLINE search (1980 to August 2000) of English-language literature was conducted using the search term argatroban to identify pertinent case reports, clinical trials, abstracts, and review articles. Additional reports were identified from the reference lists compiled in the literature reviewed, as well as from the manufacturer. DATA SYNTHESIS: Argatroban is a synthetic direct thrombin inhibitor indicated for parenteral use in the prevention and treatment of thromboembolism in patients with HIT. Its elimination half-life is approximately 40-50 minutes, and it is primarily eliminated by hepatic metabolism and biliary secretion. Compared with historical controls, argatroban-treated patients with HIT or HIT with thrombosis (HITTS) experienced lower rates of the composite end point of death, amputation, and new thrombosis. Dosing is initiated at 2 microg/kg/min and adjusted to maintain the activated partial thromboplastin time at 1.5-3 times the patient's baseline. In Japan, argatroban is approved for use in acute ischemic stroke and chronic peripheral occlusive disease. It has also been used as an alternative to unfractionated heparin (UFH) in patients with a history of HIT or HITTS undergoing percutaneous coronary intervention and other procedures. Additionally, argatroban has been compared with UFH in patients with acute myocardial infarction who were receiving thrombolytic therapy. Hemorrhage is the primary adverse event associated with argatroban. Argatroban increases the prothrombin time, making assessment of the intensity of warfarin therapy during concurrent administration more complex. CONCLUSIONS: The use of argatroban in patients with HIT and HITTS is associated with improvement in clinical outcomes compared with historical controls. Argatroban offers several practical advantages over other available agents with respect to dosing, monitoring, reversibility of effect with discontinuation of the drug, and cost.


Assuntos
Anticoagulantes/efeitos adversos , Antitrombinas/uso terapêutico , Heparina/efeitos adversos , Ácidos Pipecólicos/uso terapêutico , Trombocitopenia/induzido quimicamente , Trombocitopenia/tratamento farmacológico , Tromboembolia/tratamento farmacológico , Animais , Antitrombinas/efeitos adversos , Antitrombinas/farmacocinética , Antitrombinas/farmacologia , Arginina/análogos & derivados , Ensaios Clínicos como Assunto , Humanos , Ácidos Pipecólicos/efeitos adversos , Ácidos Pipecólicos/farmacocinética , Ácidos Pipecólicos/farmacologia , Sulfonamidas
19.
Pharmacotherapy ; 21(3): 320-37, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11253856

RESUMO

Prevention and management of acute coronary syndromes (ACS) are focal points of interest among health care providers. Acute coronary syndromes is an all-encompassing term that refers to unstable angina, non-Q wave myocardial infarction, and Q wave myocardial infarction. These syndromes are usually the result of atherosclerotic plaque rupture leading to thrombus formation in a coronary artery. Heparin and aspirin are traditional antithrombotic treatments. They typically are administered with antiischemic therapies and often with fibrinolytic agents for patients with ST segment elevation associated with acute myocardial infarction. Although aspirin and heparin are important, they have significant limitations that have prompted development of newer antithrombotic approaches. Adenosine diphosphate inhibitors have been evaluated as either alternatives or adjunctive treatment to aspirin. Glycoprotein IIb-IIIa receptor inhibitors, low-molecular-weight heparins, and direct thrombin inhibitors have been studied as concurrent therapy with, or as alternatives to, heparin.


Assuntos
Doença das Coronárias/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Doença Aguda , Doença das Coronárias/fisiopatologia , Humanos
20.
Manag Care Interface ; 14(1): 58-66, 72, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11214536

RESUMO

Coronary artery disease (CAD) is the major cause of death in the United States. This disease places a large economic burden on society stemming from both loss of productivity and use of health care resources. The primary factor that has been extensively correlated with risk for CAD is elevated cholesterol levels. The lack of efficacy with dietary restriction alone and the limitations, adverse effects, and drug interactions associated with current lipid-lowering therapies have caused health care providers to search for safer and more efficacious agents.


Assuntos
Anticolesterolemiantes/administração & dosagem , Hipercolesterolemia/tratamento farmacológico , Arteriosclerose/etiologia , HDL-Colesterol/sangue , LDL-Colesterol/classificação , Doença das Coronárias/etiologia , Complicações do Diabetes , Feminino , Humanos , Hipercolesterolemia/complicações , Hipercolesterolemia/diagnóstico , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Guias de Prática Clínica como Assunto , Fatores de Risco , Fumar/efeitos adversos , Estados Unidos
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