Transgenic maize engineered to express insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) has become widely adopted in U.S. agriculture. In 2009, Bt maize was planted on more than ...22.2 million hectares, constituting 63% of the U.S. crop. Using statistical analysis of per capita growth rate estimates, we found that areawide suppression of the primary pest Ostrinia nubilalis (European corn borer) is associated with Bt maize use. Cumulative benefits over 14 years are an estimated $3.2 billion for maize growers in Illinois, Minnesota, and Wisconsin, with more than $2.4 billion of this total accruing to non-Bt maize growers. Comparable estimates for Iowa and Nebraska are $3.6 billion in total, with $1.9 billion for non-Bt maize growers. These results affirm theoretical predictions of pest population suppression and highlight economic incentives for growers to maintain non-Bt maize refugia for sustainable insect resistance management.
The fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae), is the most important noctuid pest in the Americas and has recently become an invasive pest in Africa. A detailed ...record of S. frugiperda's host plants is essential to better understand the biology and ecology of this pest, conduct future studies, and develop Integrated Pest Management programmes. In this study, we collected and systematically arranged the fragmented bibliographic information on S. frugiperda feeding records. Furthermore, we registered new records of host plants for S. frugiperda based on eight years of surveys in Brazil. The literature review and surveys resulted in a total of 353 S. frugiperda larval host plant records belonging to 76 plant families, principally Poaceae (106), Asteraceae (31) and Fabaceae (31). The literature search revealed 274 (77 % of total) bibliographic records, while 82 (23 %) are new records from surveys in Brazil. The new comprehensive and updated host plant list will improve our understanding of pest biology and management, as well as facilitate future studies on this pest.
Integrated pest management (IPM) and insect resistance management (IRM) in various cropping systems demand a comprehensive understanding of insect behavior. Among the needed information is basic ...charaterizations of larval movement and dispersion of some insect-pests, such as the noctuids Striacosta albicosta (Smith) and Spodoptera frugiperda (J.E. Smith). We investigated the plant-to-plant movement of western bean cutworm and fall armyworm larvae in field of maize. Experiments on S. albicosta were conducted between 2008 and 2010. A main study with this pest was performed in 2012 in a randomized complete block design (RCBD) with nine replications. An S. frugiperda study was performed in 2013 in an RCBD with eight replications. The plant-to-plant movement and larval survival were measured in plots with maize nontoxic to the insects. The larval survival of S. albicosta presented high variety throughout the years. Although S. frugiperda survival was relatively low during 2013, it did not compromise the larval assessment. Larvae of both species dispersed governed by nondirectional sensory information, and presented aggregated and symmetrical distribution; however, fall armyworm remained nearer the release point. These results may help the IPM components, such as scouting and economic threshold, as well as the implementation of refuge and seed mixture strategies for IRM.
Soybean is considered one of today’s most important crops. Planted on millions of hectares worldwide, the management of soybean pests usually requires large amounts of chemicals. However, a key ...component to meet the increasing demand for food due to the rapidly growing global population is protecting crops from pests while maintaining environmental quality through ecologically and economically sound integrated pest management (IPM) practices. Not only can IPM result in more profitable agriculture due to the reduction of pest control costs but also assures equitable, secure, sufficient, and stable flows of both food and ecosystem services. Despite those ecological and economic benefits, the vast areas of cultivated soybean as well as the convenience of spraying insecticides are encouraging the adoption of prophylactic pest control as a relatively inexpensive safeguard compared to IPM practices. Thus, in this forum, we discuss the reasons for soybean IPM not reaching its potential. We give examples of how we can revive this once successful pest management program with a focus on experiences in Brazil and the USA. We analyze IPM case studies to illustrate the need for growers to have easy and fast access to IPM information on its medium- and long-term benefits. Overall, this forum highlights the importance of IPM for agricultural sustainability including ecological and financial benefits.
Spodoptera frugiperda J.E. Smith (fall armyworm) is considered one of the most destructive pests of corn throughout the Americas. Although this pest has been extensively studied, little is known ...about its larval movement and feeding behavior on reproductive compared to vegetative corn stages. Thus, we conducted studies with two corn stages (R1 and R3) and four corn plant zones (tassel, above ear, ear zone, and below ear) in the field at Concord, NE (USA), and in the field and greenhouse at Botucatu, SP (Brazil), to investigate on-plant larval movement. The effects of different corn tissues (opened tassel, closed tassel, silk, kernel, and leaf), two feeding sequence scenarios (closed tassel–leaf–silk–kernel and leaf–silk–kernel), and artificial diet (positive control) on larval survival and development were also evaluated in the laboratory. Ear zone has a strong effect on feeding choice and survival of fall armyworm larvae regardless of reproductive corn stage. Feeding site choice is made by first-instar. Corn leaves of reproductive plants were not suitable for early instar development, but silk and kernel tissues had a positive effect on survival and development of fall armyworm larvae on reproductive stage corn.
Immunoglobulin G4-related disease is a systemic fibroinflammatory process of unknown etiology, characterized by tissue infiltration by immunoglobulin G4 plasma cells. The purpose of this study was to ...retrospectively identify the spectrum of imaging features seen in immunoglobulin G4-related disease of the orbit.
This study included 27 patients with biopsy-proved immunoglobulin G4-related disease of the orbit and either a CT or MR imaging of the orbits. These CT or MR imaging examinations were evaluated for the following: extraocular muscle size, extraocular muscle tendon enlargement, lacrimal gland enlargement, infiltrative process in the orbital fat (increased attenuation on CT or abnormal signal on MR imaging), infraorbital nerve enlargement, mucosal thickening in the paranasal sinuses, and extension of orbital findings intracranially.
Extraocular muscles were enlarged in 24 of 27 (89%) patients, 21 (88%) bilaterally. In 32 of 45 (71%) affected orbits, the lateral rectus was the most enlarged muscle. In 26 (96%) patients, the tendons of the extraocular muscles were spared. Nineteen (70%) patients had lacrimal gland enlargement. Twelve (44%) patients had an infiltrative process within the orbital fat. Infraorbital nerve enlargement was seen in 8 (30%) patients. Twenty-four (89%) patients had sinus disease. Cavernous sinus or Meckel cave extension was seen in 3 (11%) patients.
In patients with extraocular muscle enlargement, particularly when the tendons are spared and the lateral rectus is the most enlarged, and even more so when other noted findings are present, immunoglobulin G4-related disease should be a leading differential consideration, even over more commonly known etiologies of extraocular muscle enlargement.
The application of volumetric techniques to preterm infants has revealed brain volume reductions. Such quantitative data are not available in routine neonatal radiologic care. The objective of this ...study was to develop simple brain metrics to compare brain size in preterm and term infants and to correlate these metrics with brain volumes from volumetric MR imaging techniques.
MR images from 189 preterm infants <30 weeks' gestational age or <1250 g birthweight scanned at term-equivalent age and 36 term infants were studied. Fifteen tissue and fluid measures were systematically evaluated on 4 selected sections. The results were correlated with total brain, gray matter, white matter, and CSF volumes.
The mean bifrontal, biparietal, and transverse cerebellar diameters were reduced (-11.6%, 95% confidence interval CI, -13.8% to -9.3%; -12%, 95% CI, -14% to -9.8%; and -8.7%, 95% CI, -10.5% to -7% respectively) and the mean left ventricle diameter was increased (+22.3%, 95% CI, 2.9%-41.6%) in preterm infants (P < .01). Strong correlations were found between the bifrontal and biparietal measures with total brain tissue volume, whereas the size of the ventricles and the interhemispheric measure correlated with CSF volume. Intraobserver reliability was high (intraclass correlation coefficients ICC, >0.7), where interobserver agreement was acceptable for tissue measures (ICC, >0.6) but lower for fluid measures (ICC, <0.4).
Simple brain metrics at term-equivalent age showed smaller brain diameters and increased ventricle size in preterm infants compared with full-term infants. These measures represent a reliable and easily applicable method to quantify brain growth and assess brain atrophy in this at-risk population.
Chromatin featuring the H3 variant CENP-A at the centromere is critical for its mitotic function and epigenetic maintenance. Assembly of centromeric chromatin is restricted to G1 phase through ...inhibitory action of Cdk1/2 kinases in other phases of the cell cycle. Here, we identify the two key targets sufficient to maintain cell-cycle control of CENP-A assembly. We uncovered a single phosphorylation site in the licensing factor M18BP1 and a cyclin A binding site in the CENP-A chaperone, HJURP, that mediated specific inhibitory phosphorylation. Simultaneous expression of mutant proteins lacking these residues results in complete uncoupling from the cell cycle. Consequently, CENP-A assembly is fully recapitulated under high Cdk activities, indistinguishable from G1 assembly. We find that Cdk-mediated inhibition is exerted by sequestering active factors away from the centromere. Finally, we show that displacement of M18BP1 from the centromere is critical for the assembly mechanism of CENP-A.
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•The HJURP conserved domain interacts with cyclin A•Timing of M18BP1 localization is controlled by T653 phosphorylation•Control of HJURP and M18BP1 suffices to cell-cycle restrict CENP-A assembly•CENP-A assembly results in functional removal of M18BP1 from centromeres
Centromeres are epigenetically defined by the heritable histone H3 variant CENP-A, whose assembly is restricted to G1 phase. Stankovic et al. show that cell-cycle coupling is achieved through inhibitory Cdk-mediated phosphorylation of two key CENP-A assembly factors, M18BP1 and HJURP, preventing unscheduled centromeric chromatin assembly outside of the G1 phase.
Abstract
Protists (eukaryotic microorganisms) commonly form symbiotic associations with crustacean zooplankton, but their diversity, prevalence and ecological roles are underestimated due to the ...limited scope of previous investigations. Using metabarcoding of the V4 region of the 18S rRNA gene, we characterized the eukaryotic microbiomes of the dominant crustacean zooplankton, specifically copepods, euphausiids, amphipods and ostracods, from the Strait of Georgia, Canada. Sequence reads from the alveolates dominated all zooplankton examined, which mostly comprised ciliates and dinoflagellates of known symbiont lineages. These lineages included not only those of parasitoids but also those of uncharacterized species. Apostome ciliate reads were the most abundant in all hosts except for cyclopoid copepods, which were dominated by the parasitic Syndiniales. Most symbiont lineages showed some degree of host preference, particularly Pseudocolliniidae ciliate parasites with ostracods, but were often detected in all hosts indicating broad host specificity. Reads from free-living protists, including diatoms and surprisingly hydrozoans, were inferred to be part of their diet. Hydrozoans may have been ingested from free organic matter, such as detritus or marine snow, suggesting a likely underestimated pathway of carbon cycling. This investigation contributes to resolving the interactions between zooplankton and protists and the potential ecological significance of symbioses on zooplankton productivity.
Background. Excessive inflammation persists despite antiretroviral treatment. Statins decrease cardiovascular (CV) disease risk by reducing low-density lipoprotein cholesterol and inflammation. We ...performed an exploratory analysis to evaluate whether statin therapy decreased risk of non-AIDS-defining events and nonaccidental death. Methods. A total of 3601 subjects not on a statin from the AIDS Clinical Trials Group Longitudinal Linked Randomized Trials cohort were included. Outcome was time to first clinical event (CV event, renal or hepatic disease, incident diabetes, thrombotic/embolic event, nontraumatic fracture, non-AIDS-defining malignancy, serious bacterial infection, or nonaccidental death); event categories were also analyzed separately. Inverse probability of treatment and censoring weighted Cox proportional hazard models were used to assess the causal statin effect. Differential statin effects by baseline covariates were evaluated. Results. Over 15 135 person-years (PY) of follow-up, 484 subjects initiated statins; 616 experienced an event (crude event rate, 4.4/100 PY on a statin and 4.1/100 PY not on a statin); the unadjusted hazard ratio (HR) was 1.17 (95% confidence interval CI, .91–1.50). In a final weighted model, the adjusted HR (AHR) was 0.81 (95% CI, .53–1.24). Results for other clinical events were similar, except for malignancies (AHR, 0.43 95% CI, .19–.94) and bacterial infections (AHR, 1.30 95% CI, .64–2.65). No differential statin effects by baseline covariates were detected. Conclusions. Although statin therapy was not associated with a reduction in time to all non-AIDS-defining event or nonaccidental death, it was associated with a statistically significant 57% reduction in non-AIDS-defining malignancies. Confirmatory studies are needed to evaluate statin-associated reduction in risk of cancer and non-AIDS-associated morbidities.
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