Immunologic activation of human syncytiotrophoblast by Plasmodium falciparum

<p>Abstract</p> <p>Background</p> <p>Malaria during pregnancy is characterized by the sequestration of malaria-infected red blood cells (iRBC) in the intervillous spaces of the placenta, often accompanied by the infiltration of maternal mononuclear cells, causing substantial maternal and foetal/infant morbidity. The iRBC bind to receptors expressed by the syncytiotrophoblast (ST). How ST responds to this interaction remains poorly understood. Because it is known that ST is immunoactive and can respond to infectious agents, the consequences of this ST-iRBC interaction should be investigated.</p> <p>Methods</p> <p>An in vitro system was used to assess the biochemical and immunological changes induced in ST by ST-adherent iRBCs. Changes in ST mitogen-activated protein kinase (MAPK) activation were assessed by immunoblotting and mRNA expression levels of selected cytokine and chemokines in primary ST bound by iRBC were determined using real-time, reverse transcription PCR. In addition, secreted cytokine and chemokine proteins were assayed by standard ELISA, and chemotaxis of PBMC was assessed using a two-chamber assay system.</p> <p>Results</p> <p>Following iRBC/ST interaction, ST C-Jun N-terminal kinase 1 (JNK1) was activated and modest increases in the mRNA expression of TGF-β and IL-8/CXCL8 were observed. In addition, this interaction increased secretion of MIF and MIP-1α/CCL3 by ST and induced migration of PBMC towards iRBC-stimulated ST.</p> <p>Conclusion</p> <p>Results from this study provide the first evidence that ST participates in shaping the local immunological milieu and in the recruitment of maternal immune cells to the maternal blood space during placental malaria infection.</p

Taxonomy and biogeography of the New Caledonian species of \u3ci\u3eXylopia\u3c/i\u3e L. (Annonaceae)

A taxonomic review of the New Caledonian representatives of the pantropical tree genus Xylopia L. (Annonaceae) is presented based on museum study of 157 collections. Distinctions are clarified among the four endemic species, two of them previously undescribed in flower and two others described in the literature from only the type collections. A key and species descriptions are presented. Xylopia pancheri Baill., the most frequently collected species, occurs in maquis environments with ultramafic rocks in the central and southern regions of the island, as well as on the Ile des Pins. Xylopia vieillardii Baill. is widespread in low elevation humid forests but the remaining two species, X. dibaccata Daniker and X. pallescens Baill., have restricted distributions and their ecology is still incompletely known. Xylopia pancheri shares similarities with the endemic Fijian species X. degeneri A.C.Sm. and X. vitiensis A.C.Sm.; the remaining three species share more traits with the Fijian endemic X. pacifica A.C.Sm. Taxonomie et biogéographie des espèces de Xylopia L. (Annonaceae) de Nouvelle-Calédonie. Une revision taxonomique des representants neo-caledoniens du genre arborescent et pantropical Xylopia L. (Annonaceae) est presentee, basee sur l’etude de 157 specimens d’herbier. Les distinctions entre les quatre especes endemiques sont clarifiees, deux d’entre-elles precedemment non decrites en fleurs, et les deux autres decrites dans la litterature uniquement des collections types. Une clef et la description des especes sont presentees. Xylopia pancheri Baill., l’espece la plus frequemment recoltee, croit en maquis sur roches ultramafiques dans les regions centrales et sud de la grande-terre, de meme que sur l’Ile des Pins. Xylopia vieillardii Baill. est largement repandue en foret humide de basse altitude, mais les deux dernieres especes, X. dibaccata Daniker et X. pallescens Baill., ont des distributions restreintes et leur ecologie est toujours incompletement connue. Xylopia pancheri montre des similarites avec les especes endemiques fidjiennes X. degeneri A.C.Sm. et X. vitiensis A.C.Sm. ; les trois autres especes semblent plus proches de l’espece endemique fidjienne X. pacifica A.C.S

Dietary supplementation with pollen enhances survival and Collembola boosts fitness of a web-building spider

Uncertainties exist about the value of non-prey food for predators that are commonly food-limited, and the dietary conditions where non-prey foods are beneficial for carnivorous species. Prior studies show that large quantities of pollen grains are intercepted in the webs of web-building spiders. We examined the nutritional benefits of pollen as a non-prey food for a common ground-dwelling, sheet web-building spider, Mermessus fradeorum (Berland) (Araneae: Linyphiidae). These predators were provided diets of prey or no prey in the presence and absence of pollen. Treatment effects were quantified by measuring predator body nutrient composition, survival, body size, and offspring production. Per unit dry weight, pollen had less nitrogen and lipids than prey, although relative quantities of these nutrients per meal were not measured. Dietary treatments altered the body tissue composition of the spiders, leading to the highest N content and lipid reserves in spiders provided with Collembola. Supplementing diets with pollen increased both juvenile and adult survival, and the greatest survivorship and offspring production was observed when spiders were provided diets of Collembola supplemented with pollen. Our results show that Collembola are high-quality prey for spiders and pollen has positive effects on nutritional status and survival of a carnivorous species. Foraging on plant material potentially promotes population growth at early and late developmental stages by supplementing diets of poor-quality prey, and preventing starvation when prey are scarce

Bifenthrin Baseline Susceptibility and Evaluation of Simulated Aerial Applications in \u3ci\u3eStriacosta albicosta\u3c/i\u3e (Lepidoptera: Noctuidae)

Striacosta albicosta (Smith) is a maize pest that has recently expanded its geographical range into the eastern United States and southeastern Canada. Aerial application of pyrethroids, such as bifenthrin, has been a major practice adopted to manage this pest. Reports of field failure of pyrethroids have increased since 2013. Striacosta albicosta populations were collected in 2016 and 2017 from maize fields in Nebraska, Kansas, and Canada and screened with bifenthrin active ingredient in larval contact dose-response bioassays. Resistance ratios estimated were generally low in 2016 (1.04- to 1.32-fold) with the highest LC50 in North Platte, NE (66.10 ng/cm2) and lowest in Scottsbluff, NE (50.10 ng/cm2). In 2017, O’Neill, NE showed the highest LC50 (100.66 ng/cm2) and Delhi, Canada exhibited the lowest (6.33 ng/cm2), resulting in a resistance ratio variation of 6.02- to 15.90-fold. Implications of bifenthrin resistance levels were further investigated by aerial application simulations. Experiments were conducted with a spray chamber where representative S. albicosta populations were exposed to labeled rates of a commercial bifenthrin formulation. Experiments resulted in 100% mortality for all populations, instars, insecticide rates, and carrier volumes, suggesting that levels of resistance estimated for bifenthrin active ingredient did not seem to impact the efficacy of the correspondent commercial product under controlled conditions. Results obtained from this research indicate that control failures reported in Nebraska could be associated with factors other than insecticide resistance, such as issues with the application technique, environmental conditions during and/or after application, or the insect’s natural behavior. Data generated will assist future S. albicosta resistance management programs

Sequence Polymorphism, Segmental Recombination and Toggling Amino Acid Residues within the DBL3X Domain of the VAR2CSA Placental Malaria Antigen

Plasmodium falciparum malaria remains one of the world's foremost health problems, primarily in highly endemic regions such as Sub-Saharan Africa, where it is responsible for substantial morbidity, mortality and economic losses. Malaria is a significant cause of severe disease and death in pregnant women and newborns, with pathogenesis being associated with expression of a unique variant of the multidomain Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) called VAR2CSA. Here, we characterize the polymorphism of the DBL3X domain of VAR2CSA and identify regions under selective pressure among placental parasites from women living in endemic western Kenya. In addition to significant levels of polymorphism, our analysis reveals evidence for diversification through intra-segmental recombination and novel mutations that likely contributed to the high number of unique VAR2CSA sequence types identified in this study. Interestingly, we also identified a number of critical residues that may be implicated in immune evasion through switching (or toggling) to alternative amino acids, including an arginine residue within the predicted binding pocket in subdomain III, which was previously implicated in binding to placental CSA. Overall, these findings are important for understanding parasite diversity in pregnant women and will be useful for identifying epitopes and variants of DBL3X to be included in a vaccine against placental malaria

Life-History Parameters of Striacosta albicosta (Lepidoptera: Noctuidae) Under Laboratory Conditions

Striacosta albicosta (Smith) is a key pest of maize and dry beans in North America. It has expanded its distribution from the western Great Plains of the United States to the Great Lakes region in the United States and Canada. There has been limited research on the baseline biological aspects of this insect under controlled conditions. The objective of this study was to detail the biological parameters of S. albicosta feeding on an artificial diet under laboratory conditions. Overall survival from neonate to adult at 26.6 ± 1°C was 36.72% and the total developmental time was approximately 110 d. Survival of the egg, larval, prepupal, and pupal stages were 75.71, 98.50, 51.78, and 95.10%, respectively. Average duration of the egg, larval, prepupal, and pupal stages was 4.64, 28.20, 41.50, and 25.91 d, respectively. During the larval stage, 92.50% of larvae developed through seven instars and the remaining through six instars. Larvae that developed through six and seven instars exhibited a mean growth ratio of 1.60 and 1.47, respectively; however, there was no difference in pupal weight. Eggs laid by field-mated moths showed a fertility of 75.71%, compared with 4.18% from laboratory-reared moths. These data suggest that S. albicosta develop primarily through seven instars and the most vulnerable developmental stage is the prepupa. Laboratory conditions strongly affected fertility success. Information presented here greatly expands our understanding of S. albicosta biology, which can be used to improve the efficiency of laboratory bioassays and management techniques for this critical crop pest

Habitual physical activity and cardiometabolic risk factors in adults with cerebral palsy

2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license(http://creativecommons.org/licenses/by/3.0/).This article has been made available through the Brunel Open Access Publishing Fund.Adults with cerebral palsy (CP) are known to participate in reduced levels of total physical activity. There is no information available however, regarding levels of moderate-to-vigorous physical activity (MVPA) in this population. Reduced participation in MVPA is associated with several cardiometabolic risk factors. The purpose of this study was firstly to compare levels of sedentary, light, MVPA and total activity in adults with CP to adults without CP. Secondly, the objective was to investigate the association between physical activity components, sedentary behavior and cardiometabolic risk factors in adults with CP. Adults with CP (n = 41) age 18–62 yr (mean ± SD = 36.5 ± 12.5 yr), classified in Gross Motor Function Classification System level I (n = 13), II (n = 18) and III (n = 10) participated in this study. Physical activity was measured by accelerometry in adults with CP and in age- and sex-matched adults without CP over 7 days. Anthropometric indicators of obesity, blood pressure and several biomarkers of cardiometabolic disease were also measured in adults with CP. Adults with CP spent less time in light, moderate, vigorous and total activity, and more time in sedentary activity than adults without CP (p < 0.01 for all). Moderate physical activity was associated with waist-height ratio when adjusted for age and sex (β = −0.314, p < 0.05). When further adjustment was made for total activity, moderate activity was associated with waist-height ratio (β = −0.538, p < 0.05), waist circumference (β = −0.518, p < 0.05), systolic blood pressure (β = −0.592, p < 0.05) and diastolic blood pressure (β = −0.636, p < 0.05). Sedentary activity was not associated with any risk factor. The findings provide evidence that relatively young adults with CP participate in reduced levels of MVPA and spend increased time in sedentary behavior, potentially increasing their risk of developing cardiometabolic disease

Exome-wide association study of pancreatic cancer risk

We conducted a case-control exome-wide association study to discover germline variants in coding regions that affect risk for pancreatic cancer, combining data from 5 studies. We analyzed exome and genome sequencing data from 437 patients with pancreatic cancer (cases) and 1922 individuals not known to have cancer (controls). In the primary analysis, BRCA2 had the strongest enrichment for rare inactivating variants (17/437 cases vs 3/1922 controls) (P=3.27x10(-6); exome-wide statistical significance threshold P&lt;2.5x10(-6)). Cases had more rare inactivating variants in DNA repair genes than controls, even after excluding 13 genes known to predispose to pancreatic cancer (adjusted odds ratio, 1.35, P=.045). At the suggestive threshold (P&lt;.001), 6 genes were enriched for rare damaging variants (UHMK1, AP1G2, DNTA, CHST6, FGFR3, and EPHA1) and 7 genes had associations with pancreatic cancer risk, based on the sequence-kernel association test. We confirmed variants in BRCA2 as the most common high-penetrant genetic factor associated with pancreatic cancer and we also identified candidate pancreatic cancer genes. Large collaborations and novel approaches are needed to overcome the genetic heterogeneity of pancreatic cancer predisposition

Movement of \u3ci\u3eStriacosta albicosta\u3c/i\u3e (Smith) (Lepidoptera: Noctuidae) Larvae on Transgenic \u3ci\u3eBt\u3c/i\u3e and Non-\u3ci\u3eBt\u3c/i\u3e Maize

Exposure of lepidopteran pests to Bacillus thuringiensis (Bt) proteins has been shown to affect the behavior of larvae, including increased movement and avoidance of Bt-expressing plants or diet. Therefore, we hypothesized that the behavior of western bean cutworm, Striacosta albicosta (Smith) (Lepidoptera: Noctuidae), an important pest of maize, could be affected when exposed to Bt plants. To test this hypothesis, we conducted a series of artificial arena and on-plant experiments to determine S. albicosta neonate behavior when exposed to Bt and non-Bt plant tissue. Video tracking experiments presented neonate larvae with the choice of Bt or non-Bt pollen in a Petri dish for 15 min while being video recorded for analysis with EthoVision software. This study showed an increase in mean velocity and total time spent moving for larvae in the presence of Cry1F vs. non-Bt when compared with Vip3A vs. non-Bt or Cry1F vs. Vip3A. However, there was no difference in total distance moved or time spent in the food zone for all scenarios. Maize tissue choice experiments allowed neonatal larvae the choice of feeding on Bt or non-Bt tassel or leaves for 9 h in Petri dish arenas. This experiment showed that larvae preferred tassel tissue over leaves but did not indicate that larvae could distinguish between Bt and non-Bt tissue. In contrast, on-plant experiments (including a whole plant neonate dispersal study under controlled conditions and an in-field silking behavior experiment) indicated that the presence of Cry1F and Vip3A Bt toxins increased plant abandonment, suggesting that larvae are able to detect and avoid Bt toxins. The discrepancy of these results is likely due to the on-plant studies providing more field-realistic environmental conditions and a longer duration of exposure to Bt toxins for the behavioral experiments. Our results represent the first steps in understanding the complex behavior of S. albicosta when exposed to Bt plants. A better understanding of the response of larvae when exposed to Bt traits can aid in the management of this pest, particularly for the design of resistance management strategies and refuge design