The invasion of North America by the Asian beetle Agrilus planipennis has caused severe economic and ecological damage to ash (Fraxinus) tree populations. Agrilus planipennis has recently entered eastern Europe and is spreading there. Many other Agrilus species can potentially become invasive pests due to the cryptic nature of their immature stages that can be inconspicuously transported within infested plant material. We review the ecology, economic impacts, and management strategies of Agrilus worldwide and highlight research gaps. Much has been learned in recent decades about the basic biology and control tactics for a few Agrilus species, especially A. planipennis. The genus Agrilus has over 3,341 described species, making it the largest genus in the Animal Kingdom. Most Agrilus are univoltine and have a narrow host range. Chemical, tactile, and visual cues of host plants are used by adult Agrilus to select suitable hosts for consumption by adults and larvae. Most Agrilus larvae develop within the cambial region, constructing galleries that effectively girdle the host plant. Mechanisms of host plant resistance are being explored. Diverse groups of natural enemies attack all life stages of Agrilus species, with some coevolved specialist parasitoids being introduced successfully to suppress A. planipennis in North America. Climate change, leading to warmer and drier conditions, will influence the distribution and population dynamics of many Agrilus species. Many research gaps still exist in the areas of biocontrol, host plant resistance, and sustainable management strategies for this important group of plant pests.

This article is a Commentary on Gossner et al . (2023), 240 : 1219–1232 .

Injectable biomaterials have been developed as potential minimally invasive therapies for treating myocardial infarction (MI) and heart failure. Christman et al. first showed that the injection of a biomaterial alone into rat myocardium can improve cardiac function after MI. More recently, hydrogel forms of decellularized extracellular matrix (ECM) materials have shown substantial promise. Here, we present the methods for fabricating an injectable cardiac-specific ECM biomaterial with demonstrated positive outcomes in small and large animal models for cardiac repair as well as initial safety in a Phase I clinical trial. This chapter also covers the methods for the injection of a biomaterial into rat myocardium using a surgical approach through the diaphragm. Although the methods shown here are for injection of an acellular biomaterial, cells or other therapeutics could also be added to the injection for testing other regenerative medicine strategies.

Many species of beetles in the family Cerambycidae use volatile pheromones to facilitate the location of mates. Visual cues may also influence the location of mates, as the adults of many species of cerambycids are often brightly patterned and diurnal. Theory predicts that combining signals or cues of different modalities (e.g., chemical, visual) to transmit information will increase the likelihood of an organism responding to this information, compared to when the signal or cue is presented alone. Here, we test the hypothesis that attraction of adults of the cerambycid beetle Megacyllene caryae (Gahan) (Coleoptera: Cerambycidae, Clytini) to their pheromones will be increased when visual cues are present. Consistent with that hypothesis, the number of beetles caught by traps baited with pheromones was increased 3.4-fold when a dead adult beetle of that species was attached to the trap, relative to those with just pheromone alone. Capture of M. caryae in our study was also influenced by the position of traps within forest stands, with traps at 100 m within stands catching 2.5x as many beetles as traps at the forest edge. These findings suggest that vision and visual cues play an important role in the location of mates by cerambycid beetles and warrant further research. Also, the inclusion of visual cues on traps may enhance the efficacy of trapping cerambycid beetles, such as the detection of species that are non-native and potentially invasive, or when monitoring species that are native and of conservation concern.

We present research on the chemical ecology of 14 species of longhorned beetles (Coleoptera: Cerambycidae), in four tribes of the subfamily Cerambycinae, conducted in east-central Illinois over 8 yr. Adult males produce aggregation-sex pheromones that attract both sexes. Twenty independent field bioassays explored the pheromone chemistry of the species and tested the possible attractive or antagonistic effects of compounds that are not produced by a given species, but are pheromone components of other species. Analyses of beetle-produced volatiles revealed compounds that had not been reported previously from several of the species. The most common pheromone component was (R)-3-hydroxyhexan-2-one, but pheromones of some species included isomers of the related 2,3-hexanediols. Males of the congeners Phymatodes amoenus (Say) and Phymatodes testaceus (L.) produced pure (R)-2-methylbutan-1-ol. Enantiomers of 2-methylbutan-1-ol also proved to be powerful synergists for Megacyllene caryae (Gahan), Sarosesthes fulminans (F.), and Xylotrechus colonus (F.). The major components of pheromone blends were consistently present in collections of headspace volatiles from male beetles, and only the major components were inherently attractive to a subset of species when tested as single components. Minor components of some species acted as powerful synergists, but in other cases appeared not to influence attraction. Among the minor components identified in headspace extracts from males, 2,3-hexanedione and 2-hydroxyhexan-3-one appeared to be analytical artifacts or biosynthetic by-products, and were neither attractants nor synergists. The antagonistic effects of minor compounds produced by heterospecific males suggest that these compounds serve to maintain prezygotic reproductive isolation among some species that share pheromone components.

Current assessment of biomaterial biocompatibility is typically implemented in wild type rodent models. Unfortunately, different characteristics of the immune systems in rodents versus humans limit the capability of these models to mimic the human immune response to naturally derived biomaterials. Here we investigated the utility of humanized mice as an improved model for testing naturally derived biomaterials. Two injectable hydrogels derived from decellularized porcine or human cadaveric myocardium were compared. Three days and one week after subcutaneous injection, the hydrogels were analyzed for early and mid-phase immune responses, respectively. Immune cells in the humanized mouse model, particularly T-helper cells, responded distinctly between the xenogeneic and allogeneic biomaterials. The allogeneic extracellular matrix derived hydrogels elicited significantly reduced total, human specific, and CD4+ T-helper cell infiltration in humanized mice compared to xenogeneic extracellular matrix hydrogels, which was not recapitulated in wild type mice. T-helper cells, in response to the allogeneic hydrogel material, were also less polarized towards a pro-remodeling Th2 phenotype compared to xenogeneic extracellular matrix hydrogels in humanized mice. In both models, both biomaterials induced the infiltration of macrophages polarized towards a M2 phenotype and T-helper cells polarized towards a Th2 phenotype. In conclusion, these studies showed the importance of testing naturally derived biomaterials in immune competent animals and the potential of utilizing this humanized mouse model for further studying human immune cell responses to biomaterials in an in vivo environment.

An increasing body of evidence suggests that the volatile pheromones of cerambycid beetles are much more diverse in structure than previously hypothesized. Here, we describe the identification, synthesis, and field testing of (2E,6Z,9Z)-2,6,9-pentadecatrienal as a male-produced aggregation-sex pheromone of the cerambycid Elaphidion mucronatum (Say) (subfamily Cerambycinae, tribe Elaphidiini). This novel structure is unlike any previously described cerambycid pheromone, and in field bioassays attracted only this species. Males produced about 9 μg of pheromone per 24 h period, and, in field trials, lures loaded with 10, 25, and 100 mg of synthetic pheromone attracted beetles of both sexes, whereas lures loaded with 1 mg of pheromone or less were not significantly attractive. Other typical cerambycine pheromones such as 3-hydroxy-2-hexanone, syn-2,3-hexanediol, and anti-2,3-hexanediol were not attractive to E. mucronatum, and when combined with (2E,6Z,9Z)-2,6,9-pentadecatrienal, the former two compounds appeared to inhibit attraction. Unexpectedly, adults of the cerambycine Xylotrechus colonus (F.) were attracted in significant numbers to a blend of 3-hydroxyhexan-2-one and (2E,6Z,9Z)-2,6,9-pentadecatrienal, even though there is no evidence that this species produces the latter compound. From timed pheromone trap catches, adults of E. mucronatum were determined to be active from dusk until shortly after midnight.

The compound 1-(1H–pyrrol-2-yl)-1,2-propanedione (“pyrrole”) is an important pheromone component of several Asian and South American species of longhorned beetles in the subfamily Cerambycinae. Here, we report the first confirmed identification of this compound as a pheromone component of a cerambycine species native to North America, the rare beetle Dryobius sexnotatus Linsley. Headspace volatiles from males contained (R)-3-hydroxyhexan-2-one and pyrrole (ratio 1:0.13), neither of which were detected in samples from a female. A field bioassay confirmed that adults of both sexes were attracted only to the binary blend of racemic 3-hydroxyhexan-2-one plus pyrrole, and not by either compound alone. Adults of another cerambycine, Xylotrechus colonus (F.), were attracted by 3-hydroxyhexan-2-one, consistent with this compound being the primary component of the pheromone of this species; attraction was not influenced by the presence of pyrrole. This study attests to the effectiveness of pheromone-baited traps in capturing rarely encountered species of cerambycids. It also provides further evidence that pyrrole represents another conserved pheromone motif within the Cerambycinae, now having been found in representatives of five cerambycid tribes from three continents.

1 A recent invader to North America, emerald ash borer Agrilus planipennis Fairmaire (Buprestidae), is expanding its western range into new habitats. We examined how site factors affect the emergence and damage caused by this beetle on the western edge of its contiguous population in eastern Wisconsin, U.S.A. We characterized forest structure and quantified signs and symptoms of A. planipennis from 2010 to 2013.2 We evaluated the potential for establishment of three host-specific parasitic Hymenoptera, released as biological control agents of A. planipennis. During June to September 2011, we conducted releases of 1500 Oobius agrili Zhang and Huang (Encyrtidae), 1900 Spathius agrili Yang (Braconidae) and 2700 Tetrastichus planipennisi Yang (Eulophidae) at the same location.3 Signs and symptoms of A. planipennis increased in abundance during the present study. Emergence of A. planipennis was greater in larger diameter trees and in subplots with more ash trees. More epicormic shoots were on the upper halves of trees in subplots with a higher percentage of ash. Fraxinus nigra exhibited a higher incidence of ruptured bark than Fraxinus pennsylvanica.4 In January 2013, we felled four infested ash trees and censused insect emergence from the entire trees. We recovered 441 A. planipennis, 41 T. planipennisi and no other released parasitoids.5 These results suggest that, of these three parasitoids, T. planipennisi has the highest likelihood of contributing to biological control in Wisconsin, although ash mortality will proceed rapidly and likely supersede the effects of the parasitoids. The best opportunity for introduced parasitoids to benefit Wisconsin may arise in post-outbreak, recovering forests.

Cardiac progenitor cells (CPCs) have rapidly advanced to clinical trials, yet little is known regarding their interaction with the microenvironment. Signaling cues present in the microenvironment change with development and disease. This work aims to assess the influence of two distinct signaling moieties on CPCs: cyclic biaxial strain and extracellular matrix. We evaluate four endpoints for improving CPC therapy: paracrine signaling, proliferation, connexin43 expression, and alignment. Vascular endothelial growth factor A (about 900 pg/mL) was secreted by CPCs cultured on fibronectin and collagen I. The application of mechanical strain increased vascular endothelial growth factor A secretion 2-4-fold for CPCs cultured on poly-L-lysine, laminin, or a naturally derived cardiac extracellular matrix. CPC proliferation was at least 25% higher on fibronectin than that on other matrices, especially for lower strain magnitudes. At 5% strain, connexin43 expression was highest on fibronectin. With increasing strain magnitude, connexin43 expression decreased by as much as 60% in CPCs cultured on collagen I and a naturally derived cardiac extracellular matrix. Cyclic mechanical strain induced the strongest CPC alignment when cultured on fibronectin or collagen I. This study demonstrates that culturing CPCs on fibronectin with 5% strain magnitude is optimal for their vascular endothelial growth factor A secretion, proliferation, connexin43 expression, and alignment.

Event Abstract Back to Event Human ECM particles produced in vitro are injectable and support angiogenesis and adipogenesis in vivo Nicolas L'Heureux1, 2*, Adam D. Young3*, Nathalie Dusserre1*, Sonya B. Sonnenberg3*, Todd D. Johnson3*, Ricardo L. Rodriguez4*, Todd N. Mcallister1* and Karen L. Christman3* 1 Cytograft Tissue Engineering, United States 2 Université de Bordeaux, U1026 BioTis, France 3 University of California, San Diego, Department of Bioengineering, Sanford Consortium for Regenerative Medicine, United States 4 CosmeticSurg, United States Cell-synthesized ECM assembled by cultured cells has emerged as a promising biological scaffold for tissue engineering[1]. Tissue-engineered blood vessels built using rolled sheets of cell-assembled matrix (CAM) have shown unprecedented long-term patency in humans[2]. In this study, the CAM was mechanically processed into particles to produce an injectable form of the material suitable for many applications including aesthetic treatments. The goal of this study was to assess 1) the composition, 2) the injectability, 3) the stability, and 4) the host’s response to the CAM. Adult human dermal fibroblasts were cultured to promote ECM production and assembly in sheets for 8 weeks as previously described[3]. Dried sheets were milled into particles that passed through a #60 sieve (250µm mesh) and sterilized by gamma irradiation. Particles composition was analyzed using mass spectroscopy, immunolabeling and biochemical testing. Particle suspensions in saline were injected subcutaneously in nude mice along with two commercially available dermal fillers: Juvéderm Ultra XC® (cross-linked hyaluronic acid-based product) and Radiesse® (hydroxyapatite-based product). Each of 12 animals received four injections (upper shoulders and thighs) and was sacrificed after 2, 4, 8 and 12 weeks (4 biopsies per material per time point). Analysis of the ECM revealed that the particles contained numerous components including fibrillar and other collagens, elastic fiber components, fibrogenesis-associated and signaling components as well as glycosaminoglycans. The particle at 175 mg/ml produced a thick solution that could be injected through a 25 Ga needle. Subcutaneous injections were easily performed and, after diffusion of the excess injected fluids (≈24hrs), a palpable and localized bolus was observed. Histologically, the collagen rich particles were easily recognizable and generated a very mild inflammatory reaction with a generally thin fibrous layer around the injection site and only sparse immune cells. Rapid fibroblastic cell migration (2 weeks) was observed between the particles followed by progressive (2-12 week) perfusion by small blood vessels (also between particles). Adipocytes were also observed between particles within the injection bolus as early as 2 weeks but were more abundant as time went by. Cells did not appear to penetrate the particles and no signs of active degradation were observed. On the other hand, Juvéderm® did not form a well-delineated injection bolus and did not elicit an active remodeling process. Radiesse generated a very significant inflammatory response throughout the study period with abundant immune cell migration, giant cell formation, thicker fibrous capsule formation and extensive angiogenesis. These results clearly demonstrate the feasibility of injecting human CAM particles, at a clinically relevant concentration, using a clinically relevant system. Further more, these results support the idea that CAM is not targeted by the non-specific immune system. Finally, CAM particles supported both angiogenesis and adipogenesis. As a whole, these results illustrate the potential of this injectable material as a new tool for long-term tissue reconstruction and rejuvenation. While previous studies have shown great clinical successes using CAM-based tissue engineering[2], this is the first study to provide safety and remodeling data in a controlled setting. Marissa Peck, David Gebhart, Sunny Virk, Casey Mount, and Heinz Scheuenstuhl; Sophia Suarez; Rebecca Braden; Jessica Ungerleider; Dr. Kent Osborn; ASEE/NSF Engineering Innovation Fellows Program; National Science Foundation Graduate Research Fellowship ProgramReferences:[1] Peck, M., Dusserre, N., McAllister, T.N. & L'Heureux, N. Tissue engineering by self-assembly. Materials Today 14, 218-224 (2011).[2] McAllister, T.N., et al. Effectiveness of haemodialysis access with an autologous tissue-engineered vascular graft: a multicentre cohort study. Lancet 373, 1440-1446 (2009).[3] L'Heureux, N., et al. Human tissue-engineered blood vessels for adult arterial revascularization. Nat. Med. 12, 361-365 (2006). Keywords: Extracellular Matrix, Biocompatibility, Tissue Regeneration, acellullar matrix Conference: 10th World Biomaterials Congress, Montréal, Canada, 17 May - 22 May, 2016. Presentation Type: Poster Topic: Regenerative medicine: biomaterials for control of tissue induction Citation: L'Heureux N, Young AD, Dusserre N, Sonnenberg SB, Johnson TD, Rodriguez RL, Mcallister TN and Christman KL (2016). Human ECM particles produced in vitro are injectable and support angiogenesis and adipogenesis in vivo. Front. Bioeng. Biotechnol. Conference Abstract: 10th World Biomaterials Congress. doi: 10.3389/conf.FBIOE.2016.01.01758 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Mar 2016; Published Online: 30 Mar 2016. * Correspondence: Dr. Nicolas L'Heureux, Cytograft Tissue Engineering, Novato, CA, United States, Email1 Dr. Adam D Young, University of California, San Diego, Department of Bioengineering, Sanford Consortium for Regenerative Medicine, La Jolla, CA, United States, adam.young08@gmail.com Dr. Nathalie Dusserre, Cytograft Tissue Engineering, Novato, CA, United States, Nathduss@yahoo.com Dr. Sonya B Sonnenberg, University of California, San Diego, Department of Bioengineering, Sanford Consortium for Regenerative Medicine, La Jolla, CA, United States, sseifnar@ucsd.edu Dr. Todd D Johnson, University of California, San Diego, Department of Bioengineering, Sanford Consortium for Regenerative Medicine, La Jolla, CA, United States, nso@ucsd.edu Dr. Ricardo L Rodriguez, CosmeticSurg, Baltimore, MD, United States, dr.rodriguez@me.com Dr. Todd N Mcallister, Cytograft Tissue Engineering, Novato, CA, United States, Todd@cytograft.com Dr. Karen L Christman, University of California, San Diego, Department of Bioengineering, Sanford Consortium for Regenerative Medicine, La Jolla, CA, United States, christman@eng.ucsd.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Nicolas L'Heureux Adam D Young Nathalie Dusserre Sonya B Sonnenberg Todd D Johnson Ricardo L Rodriguez Todd N Mcallister Karen L Christman Google Nicolas L'Heureux Adam D Young Nathalie Dusserre Sonya B Sonnenberg Todd D Johnson Ricardo L Rodriguez Todd N Mcallister Karen L Christman Google Scholar Nicolas L'Heureux Adam D Young Nathalie Dusserre Sonya B Sonnenberg Todd D Johnson Ricardo L Rodriguez Todd N Mcallister Karen L Christman PubMed Nicolas L'Heureux Adam D Young Nathalie Dusserre Sonya B Sonnenberg Todd D Johnson Ricardo L Rodriguez Todd N Mcallister Karen L Christman Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Although surgical and endovascular revascularization can be performed in peripheral arterial disease (PAD), 40% of patients with critical limb ischemia do not have a revascularization option. This study examines the efficacy and mechanisms of action of acellular extracellular matrix-based hydrogels as a potential novel therapy for treating PAD. We tested the efficacy of using a tissue-specific injectable hydrogel derived from decellularized porcine skeletal muscle (SKM) and compared this to a new human umbilical cord-derived matrix (hUC) hydrogel, which could have greater potential for tissue regeneration because of the younger age of the tissue source. In a rodent hindlimb ischemia model, both hydrogels were injected 1-week post-surgery and perfusion was regularly monitored with laser speckle contrast analysis to 35 days post-injection. There were significant improvements in hindlimb tissue perfusion and perfusion kinetics with both biomaterials. Histologic analysis indicated that the injected hydrogels were biocompatible, and resulted in arteriogenesis, rather than angiogenesis, as well as improved recruitment of skeletal muscle progenitors. Skeletal muscle fiber morphology analysis indicated that the muscle treated with the tissue-specific SKM hydrogel more closely matched healthy tissue morphology. Whole transcriptome analysis indicated that the SKM hydrogel caused a shift in the inflammatory response, decreased cell death, and increased blood vessel and muscle development. These results show the efficacy of an injectable ECM hydrogel alone as a potential therapy for treating patients with PAD. Our results indicate that the SKM hydrogel improved functional outcomes through stimulation of arteriogenesis and muscle progenitor cell recruitment.

The Muller F element (4.2 Mb, ~80 protein-coding genes) is an unusual autosome of Drosophila melanogaster; it is mostly heterochromatic with a low recombination rate. To investigate how these properties impact the evolution of repeats and genes, we manually improved the sequence and annotated the genes on the D. erecta, D. mojavensis, and D. grimshawi F elements and euchromatic domains from the Muller D element. We find that F elements have greater transposon density (25–50%) than euchromatic reference regions (3–11%). Among the F elements, D. grimshawi has the lowest transposon density (particularly DINE-1: 2% vs. 11–27%). F element genes have larger coding spans, more coding exons, larger introns, and lower codon bias. Comparison of the Effective Number of Codons with the Codon Adaptation Index shows that, in contrast to the other species, codon bias in D. grimshawi F element genes can be attributed primarily to selection instead of mutational biases, suggesting that density and types of transposons affect the degree of local heterochromatin formation. F element genes have lower estimated DNA melting temperatures than D element genes, potentially facilitating transcription through heterochromatin. Most F element genes (~90%) have remained on that element, but the F element has smaller syntenic blocks than genome averages (3.4–3.6 vs. 8.4–8.8 genes per block), indicating greater rates of inversion despite lower rates of recombination. Overall, the F element has maintained characteristics that are distinct from other autosomes in the Drosophila lineage, illuminating the constraints imposed by a heterochromatic milieu.

PURPOSE:The purpose of this study was to characterize and quantitatively analyze human cardiac extracellular matrix (ECM) isolated from six different cadaveric donor hearts.EXPERIMENTAL DESIGN:ECM was isolated by decellularization of six human cadaveric donor hearts and characterized by quantifying sulfated glycosaminoglycan content (sGAG) and via PAGE. The protein content was then quantified using ECM-targeted Quantitative conCATamers (QconCAT) by LC-SRM analysis using 83 stable isotope labeled (SIL) peptides representing 48 different proteins. Nontargeted global analysis was also implemented using LC-MS/MS.RESULTS:The sGAG content, PAGE, and QconCAT proteomics analysis showed significant variation between each of the six patient samples. The quantitative proteomics indicated that the majority of the protein content was composed of various fibrillar collagen components. Also, quantification of difficult to remove cellular proteins represented less than 1% of total protein content, which is very low for a decellularized biomaterial. Global proteomics identified over 200 distinct proteins present in the human cardiac ECM.CONCLUSION AND CLINICAL RELEVANCE:In conclusion, quantification and characterization of human myocardial ECM showed significant patient-to-patient variability between the six investigated patients. This is an important outcome for the development of allogeneic derived biomaterials and for increasing our understanding of human myocardial ECM composition.

Heart failure (HF) after myocardial infarction (MI) is a leading cause of death in the western world with a critical need for new therapies. A previously developed injectable hydrogel derived from porcine myocardial matrix (PMM) has had successful results in both small and large animal MI models. In this study, we sought to evaluate the impact of tissue source on this biomaterial, specifically comparing porcine and human myocardium sources. We first developed an analogous hydrogel derived from human myocardial matrix (HMM). The biochemical and physical properties of the PMM and HMM hydrogels were then characterized, including residual dsDNA, protein content, sulfated glycosaminoglycan (sGAG) content, complex viscosity, storage and loss moduli, and nano-scale topography. Biochemical activity was investigated with in vitro studies for the proliferation of vascular cells and differentiation of human cardiomyocyte progenitor cells (hCMPCs). Next, in vivo gelation and material spread were confirmed for both PMM and HMM after intramyocardial injection. After extensive comparison, the matrices were found to be similar, yet did show some differences. Because of the rarity of collecting healthy human hearts, the increased difficulty in processing the human tissue, shifts in ECM composition due to aging, and significant patient-to-patient variability, these studies suggest that the HMM is not a viable option as a scalable product for the clinic; however, the HMM has potential as a tool for in vitro cell culture.

Two parasitoids, the introduced specialist Spathius agrili Yang (Braconidae), and the native generalist Spathius floridanus Ashmead, have been proposed as biological control agents of the emerald ash borer, Agrilus planipennis Fairmaire (Buprestidae). However, little is known about their host-location behaviors. We evaluated responses to their host complex, Fraxinus pennsylvanica stem tissue, F. pennsylvanica foliage, and an A. planipennis larva within a stem. Experiments were conducted in a Y-tube olfactometer, using wasps reared on A. planipennis larvae in F. pennsylvanica stems. Naive S. agrili were attracted to the entire complex, and to leaf tissue, relative to blanks. S. agrili were also more attracted to stems containing larvae and leaf tissue together than leaf tissue alone. Naive S. floridanus were attracted to larvae within stems, but nothing else. A further distinction is that S. agrilli moved more, in the presence of foliage. Thus, S. agrili and S. floridanus appear to employ different host-location strategies. The former is attracted to host plant cues, which then elicit increased searching, whereas the latter is only attracted to infested tissue directly. We found no evidence that oviposition influences attraction by S. agrili, suggesting other forms of experience should be evaluated for potential sources of learned cues. Further, S. agrili that declined opportunities to oviposit oriented away from host-associated cues, suggesting distinct behavioral sequences occur by females that are not reproductively ready. Further understanding of host-location behavior may improve biological control by these parasitoids, by suggesting strategies for pre-release conditioning and providing tools for assessing post-release establishment. (C) 2014 Elsevier Inc. All rights reserved.

With age, or after injury, subcutaneous adipose and conjunctive tissue loss can cause poor aesthetic appearance. Current injectable tissue fillers trigger foreign body responses that eventually lead to their degradation or encapsulation. The ideal dermal filler would provide initial structural support but also trigger a regenerative process and lead to the creation of a new permanent tissue. The goal of this project is to develop a new class of fillers that provides long‐term results by triggering the regeneration of a stable, living and vascularized adipose tissue.

Introduction: Cell therapies have grown in popularity for myocardial regeneration post-infarction, but still suffer from poor retention, maturation and integration of delivered cells. Mechanical strain has been shown to alter cell size, shape, adherence and gene expression in cardiac cells. As a more recently identified cell type, the effect of mechanical strain on cardiac progenitor cells (CPCs) is unknown. This work aims to elucidate the role mechanical strain plays in CPC phenotype and if this response is matrix protein specific. We hypothesize that mechanical strain will improve CPC alignment and potential for connectivity. Methods: To examine the role of mechanical strain on CPCs, CPCs were seeded on FlexCell plates in the presence of a naturally-derived cardiac extracellularmatrix (cECM), collagen I (COL) or no protein (TCP) and strained 0% (static) or 10% at 1 Hz for 24 hours in a BioFlex system. CPC elongation, alignment, and size were evaluated by rhodamine-phalloidin staining. Connexin-43 expression was measured by Western and normalized to GAPDH. Data were analyzed by two-way ANOVA and Bonferroni post-test. Results: CPC area, independent of culture conditions, was 1020 ± 40 um2, corresponding to neonatal cardiomyocyte area. The aspect ratio (major/minor axis) of CPCs showed a trend for increased elongation with strain at (e.x. 2.0±0.2 for unstrained cECM compared to 2.7±0.1 for strained cECM; n=4, p>0.05). Static culture conditions, independent of matrix coating, showed 20±3% alignment of CPCs. Under strain, alignment increased to 30±2% on COL (n=4; p>0.05 for strained COL verus static COL) and 48±8% on cECM (n=4; p< 0.01 for strained cECM versus strained COL and p<0.001 for strained cECM verus static cECM). A fold change >2 for connexin-43 protein in strained versus static conditions, independent of matrix, was observed (n=2, p>0.05) and confirmed by immunocytochemistry. Conclusion: This work suggests that mechanical strain alters CPC phenotype. Increased strain-induced alignment appears to be matrix dependent. In conclusion, these studies provide insight into the role of both mechanical forces and biochemical responses in the function of CPCs; which could lead to improved outcomes following cellular transplantation.

INTRODUCTION:Heart failure following myocardial infarction (MI) impacts millions of people each year in the US. The field of tissue engineering has developed several potential therapies for treating MI including injectable acellular hydrogels. These injectable biomaterials can either be synthetic or naturally derived, and have the potential to be delivered minimally invasively.AREAS COVERED:This review covers the different methods of delivery and presents the initial work on the use of injectable biomaterial scaffolds alone to improve cardiac function post-MI. Several naturally derived materials including alginate, collagen, chitosan, decellularized tissues, fibrin, hyaluronic acid, keratin, and Matrigel, as well as a few synthetic materials have shown promise on their own without the addition of therapeutics such as cells or growth factors. These biomaterials can be potentially delivered via endocardial, epicardial, or intracoronary injections and some can even utilize current catheter technology, indicating a potential for avoiding invasive surgical procedures. Once injected into the wall of the heart, these hydrogels create a scaffold that provides biochemical and structural cues, and the ability for cellular infiltration and remodeling of the local environment.EXPERT OPINION:Injectable biomaterials have several crucial challenges that should be over come to design optimal therapies for MI and heart failure, including optimizing material properties, methods of injection and understanding the mechanisms of action. But, studies in both small and large animals have shown significant improvement in important parameters including wall thickness, vascularization of the ischemic region, left ventricular volumes, and cardiac function. Thus, the application of injectable biomaterials shows promise for developing into new therapies to treat MI, potentially improving millions of lives.

In the native tissue, the interaction between cells and the extracellular matrix (ECM) is essential for cell migration, proliferation, differentiation, mechanical stability, and signaling. It has been shown that decellularized ECMs can be processed into injectable formulations, thereby allowing for minimally invasive delivery. Upon injection and increase in temperature, these materials self-assemble into porous gels forming a complex network of fibers with nanoscale structure. In this study we aimed to examine and tailor the material properties of a self-assembling ECM hydrogel derived from porcine myocardial tissue, which was developed as a tissue specific injectable scaffold for cardiac tissue engineering. The impact of gelation parameters on ECM hydrogels has not previously been explored. We examined how modulating pH, temperature, ionic strength, and concentration affected the nanoscale architecture, mechanical properties, and gelation kinetics. These material characteristics were assessed using scanning electron microscopy, rheometry, and spectrophotometry, respectively. Since the main component of the myocardial matrix is collagen, many similarities between the ECM hydrogel and collagen gels were observed in terms of the nanofibrous structure and modulation of properties by altering ionic strength. However, variation from collagen gels was noted for the gelation temperature along with varied times and rates of gelation. These discrepancies when compared to collagen are likely due to the presence of other ECM components in the decellularized ECM based hydrogel. These results demonstrate how the material properties of ECM hydrogels could be tailored for future in vitro and in vivo applications.