57 research outputs found

    Agroecological factors impacting stem borer (Lepidoptera: Crambidae) dynamics in Gulf Coast sugarcane and rice

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    Diatraea saccharalis (F.) and Eoreuma loftini (Dyar) are stem boring pests of sugarcane (Saccharum spp.) and rice (Oryza sativa L.) crops in the Gulf Coast region. Studies were conducted to determine the role of agroecological factors, including predator disruptions, alternate hosts, and crop phenological conditions, on stem borer populations. The year after Hurricane Rita storm surge flooded sugarcane in Louisiana, a 71% reduction in the predaceous Solenopsis invicta Buren was recorded. Even with a 2.4-fold increase in the number of insecticide applications used for D. saccharalis management in flooded fields, growers still incurred higher injury. In two field experiments, October sampling showed that sugarcane planted in early August harbored 4.7 to 19.0-fold greater D. saccharalis infestations than September plantings. Although there is a potential for increased D. saccharalis overwintering populations in early plantings, differences in infestations were not recorded during the spring. Sentinel plant experiments confirmed that a number of non-crop grasses are stem borer hosts. Subsequently, sampling along transects every 6-8 wk compared stem borer infestations in non-crop grasses adjacent to rice fields. While D. saccharalis densities were relatively low, E. loftini average densities were 0.3 to 5.7 immatures/m2 throughout a 2-yr period. A greenhouse study showed that rice is more preferred for E. loftini oviposition than the primary non-crop hosts johnsongrass [Sorghum halepense (L.) Pers.] and Vasey’s grass (Paspalum urvillei Steud.). In addition, E. loftini larval development duration in degree-days above a threshold temperature is 1.7-fold greater on johnsongrass and Vasey’s grass than on rice. A 2-yr rice study showed that a lower than traditional harvest cutting height (20 vs. 40 cm) reduced E. loftini infestations by 70 to 81% whereas D. saccharalis infestations were not changed. Furthermore, rice stubble under favorable conditions represents an overwintering habitat in addition to non-crop hosts. This research showed that predator disruptions, sugarcane planting dates, non-crop hosts, and rice stubble management impact stem borer populations when they are traditionally left unmanaged. Thus, the evaluation of a stem borer management strategy that targets infestations in late season sugarcane and rice, but also in non-crop hosts, is warranted

    Effects of chlorantraniliprole and thiamethoxam rice seed treatments on egg numbers and first instar survival of Lissorhoptrus oryzophilus (Coleoptera: Curculionidae)

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    Effects of treatment of rice seeds with an anthranilic diamide, chlorantraniliprole, and a neonicotinoid, thiamethoxam, on egg laying and first instar survival in rice water weevil, Lissorhoptrus oryzophilus Kuschel, were examined under greenhouse conditions. Exposure of adult weevils to rice (6-7 leaf stage) grown from seeds treated with chlorantraniliprole and thiamethoxam resulted in reduction in numbers of eggs and first instars. The low egg numbers by adults exposed to chlorantraniliprole-treated plants was confirmed as a sublethal effect on adults: adult survival was not impacted after 4 d of feeding on foliage from chlorantraniliprole-treated plants but the number of eggs laid by these weevils was reduced when released on untreated plants. Furthermore, a comparison of first instar emergence from chlorantraniliprole-treated plants and from untreated plants infested with weevils previously exposed to this chemical suggested that chlorantraniliprole was also reducing egg or first instar survival. In contrast, adults that fed on foliage from thiamethoxam-treated plants showed increased mortality. Possible sublethal effects of thiamethoxam on the number of eggs laid by adults were investigated by infesting untreated plants with weevils that survived exposure to thiamethoxam via foliar feeding (7 Όg active ingredient / seed). Prior exposure to thiamethoxam through adult feeding reduced egg numbers. However, potential larvicidal or ovicidal effects of thiamethoxam seed treatments could not be detected in this study because of low first instar emergence from both thiamethoxam-treated plants and from untreated plants infested with weevils previously exposed to this chemical. These experiments revealed that the two seed treatments accomplish weevil control in different ways. © 2013 Entomological Society of America

    IMGT/V-QUEST: the highly customized and integrated system for IG and TR standardized V-J and V-D-J sequence analysis

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    IMGT/V-QUEST is the highly customized and integrated system for the standardized analysis of the immunoglobulin (IG) and T cell receptor (TR) rearranged nucleotide sequences. IMGT/V-QUEST identifies the variable (V), diversity (D) and joining (J) genes and alleles by alignment with the germline IG and TR gene and allele sequences of the IMGT reference directory. New functionalities were added through a complete rewrite in Java. IMGT/V-QUEST analyses batches of sequences (up to 50) in a single run. IMGT/V-QUEST describes the V-REGION mutations and identifies the hot spot positions in the closest germline V gene. IMGT/V-QUEST can detect insertions and deletions in the submitted sequences by reference to the IMGT unique numbering. IMGT/V-QUEST integrates IMGT/JunctionAnalysis for a detailed analysis of the V-J and V-D-J junctions, and IMGT/Automat for a full V-J- and V-D-J-REGION annotation. IMGT/V-QUEST displays, in ‘Detailed view’, the results and alignments for each submitted sequence individually and, in ‘Synthesis view’, the alignments of the sequences that, in a given run, express the same V gene and allele. The ‘Advanced parameters’ allow to modify default parameters used by IMGT/V-QUEST and IMGT/JunctionAnalysis according to the users’ interest. IMGT/V-QUEST is freely available for academic research at http://imgt.cines.f

    “Nanostandardization” in action: implementing standardization processes in a multidisciplinary nanoparticle-based research and development project

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    Nanomaterials have attracted much interest in the medical field and related applications as their distinct properties in the nano-range enable new and improved diagnosis and therapies. Owing to these properties and their potential interactions with the human body and the environment, the impact of nanomaterials on humans and their potential toxicity have been regarded a very significant issue. Consequently, nanomaterials are the subject of a wide range of cutting-edge research efforts in the medical and related fields to thoroughly probe their potential beneficial utilizations and their more negative effects. We posit that the lack of standardization in the field is a serious shortcoming as it has led to the establishment of methods and results that do not ensure sufficient consistency and thus in our view can possibly result in research outputs that are not as robust as they should be. The main aim of this article is to present how NanoDiaRA, a large FP7 European multidisciplinary project that seeks to investigate and develop nanotechnology-based diagnostic systems, has developed and implemented robust, standardized methods to support research practices involving the engineering and manipulation of nanomaterials. First, to contextualize this research, an overview of the measures defined by different regulatory bodies concerning nano-safety is presented. Although these authorities have been very active in the past several years, many questions remain unanswered in our view. Second, a number of national and international projects that attempted to ensure more reliable exchanges of methods and results are discussed. However, the frequent lack of publication of procedures and protocols in research can often be a hindrance for sharing those good practices. Subsequently, the efforts made through NanoDiaRA to introduce standardized methods and techniques to support the development and utilization of nanomaterials are discussed in depth. A series of semi-structured interviews were conducted with the partners of this project, and the interviews were analyzed thematically to highlight the determined efforts of the researchers to standardize their methods. Finally, some recommendations are made towards the setting up of well-defined methods to support the high-quality work of collaborative nanoparticle-based research and development projects and to enhance standardization processes

    Rheumatoid arthritis response to treatment across IgG1 allotype - anti-TNF incompatibility: a case-only study.

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    INTRODUCTION: We have hypothesized that incompatibility between the G1m genotype of the patient and the G1m1 and G1m17 allotypes carried by infliximab (INX) and adalimumab (ADM) could decrease the efficacy of these anti-tumor necrosis factor (anti-TNF) antibodies in the treatment of rheumatoid arthritis (RA). METHODS: The G1m genotypes were analyzed in three collections of patients with RA totaling 1037 subjects. The first, used for discovery, comprised 215 Spanish patients. The second and third were successively used for replication. They included 429 British and Greek patients and 393 Spanish and British patients, respectively. Two outcomes were considered: change in the Disease Activity Score in 28 joint (ΔDAS28) and the European League Against Rheumatism (EULAR) response criteria. RESULTS: An association between less response to INX and incompatibility of the G1m1,17 allotype was found in the discovery collection at 6 months of treatment (P = 0.03). This association was confirmed in the replications (P = 0.02 and 0.08, respectively) leading to a global association (P = 0.001) that involved a mean difference in ΔDAS28 of 0.4 units between compatible and incompatible patients (2.3 ± 1.5 in compatible patients vs. 1.9 ± 1.5 in incompatible patients) and an increase in responders and decrease in non-responders according to the EULAR criteria (P = 0.03). A similar association was suggested for patients treated with ADM in the discovery collection, but it was not supported by replication. CONCLUSIONS: Our results suggest that G1m1,17 allotypes are associated with response to INX and could aid improved therapeutic targeting in RA

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

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    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

    Activity of chlorantraniliprole and thiamethoxam seed treatments on life stages of the rice water weevil as affected by the distribution of insecticides in rice plants

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    BACKGROUND: The systemic insecticides chlorantraniliprole (CAP) and thiamethoxam (TMX), applied to rice as seed treatments, may affect multiple life stages of the rice water weevil, Lissorhoptrus oryzophilus. Effects of CAP and TMX on adult survival, egg-laying and first- and late-instar survivals were determined by infesting plants treated as seeds with different rates of insecticides. The biological activity was related to insecticidal concentrations in leaves, shoots and roots. RESULTS: CAP did not affect adult survival but decreased egg numbers and reduced the survival of the first and late instars. The greatest reduction in weevil population occurred in late instars feeding on roots. In contrast, TMX reduced adult survival and egg and larval numbers. The high biological activity of CAP on root-feeding stages was consistent with the accumulation of CAP in roots, whereas in TMX-treated plants the high activity on adults correlated with high concentrations of TMX in leaves and stems. CONCLUSIONS: The differential activity of insecticides on adults suggests poor inherent potency of CAP as an adulticide and/or its limited systemicity in foliage. The distribution of insecticide in specific plant parts can be attributed to the different physicochemical properties of CAP and TMX. The field implications of this research on management of L. oryzophilus are discussed. © 2013 Society of Chemical Industry
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