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At the neuromuscular junction (NMJ), postsynaptic ionotropic acetylcholine receptors (AChRs) transduce a chemical signal released from a cholinergic motor neuron into an electrical signal to induce muscle contraction. To identify regulators of postsynaptic function, we conducted a genome-wide RNAi screen for genes required for proper response to levamisole, a pharmacological agonist of ionotropic L-AChRs at the Caenorhabditis elegans NMJ. A total of 117 gene knockdowns were found to cause levamisole hypersensitivity, while 18 resulted in levamisole resistance. Our screen identified conserved genes important for muscle function including some that are mutated in congenital myasthenic syndrome, congenital muscular dystrophy, congenital myopathy, myotonic dystrophy, and mitochondrial myopathy. Of the genes found in the screen, we further investigated those predicted to play a role in endocytosis of cell surface receptors. Loss of the Epsin homolog epn-1 caused levamisole hypersensitivity and had opposing effects on the levels of postsynaptic L-AChRs and GABAA receptors, resulting in increased and decreased abundance, respectively. We also examined other genes that resulted in a levamisole-hypersensitive phenotype when knocked down including gas-1, which functions in Complex I of the mitochondrial electron transport chain. Consistent with altered ATP synthesis impacting levamisole response, treatment of wild-type animals with levamisole resulted in L-AChR–dependent depletion of ATP levels. These results suggest that the paralytic effects of levamisole ultimately lead to metabolic exhaustion.

At the neuromuscular junction (NMJ), postsynaptic ionotropic acetylcholine receptors (AChRs) transduce a chemical signal released from a cholinergic motor neuron into an electrical signal to induce muscle contraction. To identify regulators of postsynaptic function, we conducted a genome-wide RNAi screen for genes required for proper response to levamisole, a pharmacological agonist of ionotropic L-AChRs at theCaenorhabditis elegansNMJ. A total of 117 gene knockdowns were found to cause levamisole hypersensitivity, while 18 resulted in levamisole resistance. Our screen identified conserved genes important for muscle function including some that are mutated in congenital myasthenic syndrome, congenital muscular dystrophy, congenital myopathy, myotonic dystrophy, and mitochondrial myopathy. Of the genes found in the screen, we further investigated those predicted to play a role in endocytosis of cell surface receptors. Loss of the Epsin homologepn-1had opposing effects on the levels of postsynaptic L-AChRs and GABAAreceptors, resulting in increased and decreased abundance, respectively. This disrupts the balance of postsynaptic excitatory and inhibitory signaling, causing levamisole hypersensitivity. We also examined other genes that resulted in a levamisole hypersensitive phenotype when knocked down includinggas-1, which functions in Complex I of the mitochondrial electron transport chain. Consistent with altered ATP synthesis impacting levamisole response, treatment of wild-type animals with levamisole resulted in L-AChR dependent depletion of ATP levels. These results suggest that the paralytic effects of levamisole ultimately lead to metabolic exhaustion.

Ithaka S+R’s Research Support Services Program investigates how the research support needs of scholars vary by discipline. In 2017 and 2018 Ithaka S+R examined the changing research methods and practices of civil and environmental engineering scholars in the United States with the goal of identifying services to better support them. The goal of this report is to provide actionable findings for the organizations, institutions, and professionals who support the research processes of civil and environmental engineering scholars. The project was undertaken collaboratively with research teams at 11 academic libraries in the United States and Canada.[1] We are delighted to have the American Society of Civil Engineers (ASCE) as project partner and sponsor. Angela Cochran, Associate Publisher at ASCE, served as a project advisor. The project also relied on scholars who are leaders in the field to engage in an advisory capacity. We thank Franz-Joseph Ulm (Massachusetts Institute of Technology), Antonio Nanni (University of Miami), Anand Puppala (University of Texas at Arlington), and Roger Ghanem (University of Southern California) for their thoughtful contributions. Many of the challenges civil and environmental engineering researchers face are shared with other STEM disciplines – a competitive funding landscape, a fraught peer review system, complex data management requirements. Yet this applied field presents unique opportunities for academic support service providers. Fundamentally focused on finding practicable solutions to real-world problems, civil and environmental engineering is highly collaborative, interdisciplinary, and close to relevant industries. Yet these synergies are largely built on old-fashioned research infrastructures. Inefficient systems for sharing data impede innovation, tools for discovering data and gray literature are inadequate, and career incentives discourage investment in the industry partnerships that shape the field’s future directions. Successful interventions will need to recognize and leverage the field’s strength in building personal, targeted, collaborative relationships, both within academia and between academia and industry. This report describes the distinctive ways in which civil and environmental engineering scholars conduct their research and draws out broad implications for academic libraries, universities, publishers, research technology developers, and others. American Society of Civil Engineers (ASCE)

The first few centuries of the second millennium saw drastic changes in Coastal California and the American Southwest. In both areas, systems of internal trade intensified, and social systems sped down a path of increasing complexity. Following Peter Peregrine and Stephen Lekson (2006, 2012), we do not believe that these neighboring developments were purely coincidental. Rather, we see California and the Southwest as components in a continental-wide interaction system spanning both North and Central America. We argue that prehistoric interaction between the two regions was regular and sustained and that economic or political developments in one area are likely to have had important implications in the other. Specifically, we outline archaeological and ethnohistoric evidence for the trade of goods between the two areas, with shell beads and asphaltum moving east from coastal California in exchange for Southwestern ceramics and textiles. Rather than seeing each area as a case study in autochthonous social development, we argue that a regional synthesis of economic interactions and connectivity will build toward a better understanding of social changes in both regions. [world systems theory, trade and exchange, North America] RESUMEN Durante los primeros siglos del segundo milenio muchos cambios importantes ocurrieron en las regiones representadas por la Costa de California y el Suroeste de los Estados Unidos. En estas dos regiones, los sistemas de intercambio se intensificaron, y los sistemas sociales se desarrollaron en una ruta de complejidad creciente. Siguiendo el trabajo de Peter Peregrine y Stephen Lekson (2006, 2012) nosotros no creemos que estos desarrollos sean una coincidencia. Por el contrario, vemos a California y el Suroeste como componentes en un sistema de interaccion continental que abarca todo Centroamerica y America del Norte. Debatimos que la interaccion prehistorica entre las dos regiones era regular y sostenida, y que los desarrollos economicos o politicos en una de los areas probablemente haya tenido consecuencias importantes en la otra. Especificamente, describimos la evidencia arqueologica y etnohistorica sobre intercambio entre las dos areas, con cuentas de conchas y asfalto moviendose hacia el este desde la costa de California, a cambio de ceramica y textiles desde el Suroeste. Debatimos que una sintesis regional de las interacciones economicas puede construir una mejor comprension del desarrollo y cambio social en ambas regiones. [teoria del sistema-mundo, comercio e intercambio, arqueologia de America del Norte]

Cues previously paired with rewarding stimuli induce a time-dependent increase in the motivational craving state (incubation of craving). Whether there is an increase in craving for high-fat (HF) food over time, which may contribute to overeating and obesity, has not been determined. We hypothesized that cues paired with HF pellets would elicit a greater incubation of craving effect than those paired with standard chow (SC) pellets. Rats exposed to cues associated with either HF or SC pellets demonstrated equivalent levels of craving over an abstinence period of 30 days. Diet preference tests between SC pellets and LabDiet revealed that SC pellets were preferred over LabDiet. Rats reared on SC pellets exclusively, did not display incubation of craving for SC pellets, suggesting that prior history with the food plays an important role in cue-induced seeking behavior. Results identified cues previously associated with food undergo a comparable magnitude of incubation of craving. When ingestive behavior was measured after 30 days of abstinence, rats significantly increased their consumption of HF pellets. Our results indicate that food cues gain importance over time, trigger increased approach behaviors and increased consumption of HF food following abstinence. This may contribute to overeating and the development of obesity.

The design of a projectile delivery system often plays a critical role in the durability and breakage patterns associated with spent projectile points. This paper presents the results of an experimental project designed to examine projectile point durability and breakage patterns between three different hafting methods. Specifically, we compare two asphaltum hafting techniques drawn from archaeological and ethnohistoric accounts from the Central Valley of California with a more stereotypical cross-hatched sinew hafting system. Our results suggest a small yet statistically significant increase in durability among asphaltum hafted points, opening the door to future research on these ethnohistorically documented hafting techniques.

Recent collaborative efforts have subclassified malignant glioblastomas into 4 clinical relevant subtypes based on their signature genetic lesions. Platelet-derived growth factor receptor α (PDGFRA) overexpression is concomitant with a loss of cyclin-dependent kinase inhibitor 2A (CDKN2A) locus (encoding P16INK4A and P14ARF) in a large number of tumors within one subtype of glioblastomas. Here we report that activation of PDGFRα conferred tumorigenicity to Ink4a/Arf-deficient mouse astrocytes and human glioma cells in the brain. Restoration of p16INK4a but not p19ARF suppressed PDGFRα-promoted glioma formation. Mechanistically, abrogation of signaling modules in PDGFRα that lost capacity to bind to SHP-2 or PI3K significantly diminished PDGFRα-promoted tumorigenesis. Furthermore, inhibition of SHP-2 by shRNAs or pharmacological inhibitors disrupted the interaction of PI3K with PDGFRα, suppressed downstream AKT/mTOR activation, and impaired tumorigenesis of Ink4a/Arf-null cells, whereas expression of an activated PI3K mutant rescued the effect of SHP-2 inhibition on tumorigenicity. PDGFRα and PDGF-A are co-expressed in clinical glioblastoma specimens, and such co-expression is linked with activation of SHP-2/AKT/mTOR signaling. Together, our data suggest that in glioblastomas with Ink4a/Arf deficiency, overexpressed PDGFRα promotes tumorigenesis through the PI3K/AKT/mTOR-mediated pathway regulated by SHP-2 activity. These findings functionally validate the genomic analysis of glioblastomas and identify SHP-2 as a potential target for treatment of glioblastomas.

Platelet-derived growth factor (PDGF) signaling is essential for processes involving cell motility and differentiation during embryonic development in a wide variety of organisms including the mouse, frog, zebrafish, and sea urchin. In early Xenopus laevis embryos, PDGF-AA provides guidance cues for the migration of anterior mesendoderm cells as they move across a fibronectin-rich extracellular matrix. The long form of PDGF-A includes a positively charged carboxyl-terminal retention motif that can interact with the extracellular matrix and heparan sulfate proteoglycans (HSPGs). In this study we demonstrate that PDGF-AA binds directly to fibronectin and that this association is greatly enhanced by heparin. The PDGF-AA-fibronectin binding occurs across a broad range of pHs (5.5–9), which is significant because the PDGF-guided migration of Xenopus mesendoderm cells occurs under basic extracellular conditions (pH 8.4). We further demonstrate that endogenous HSPG's are required for the PDGF-AA-guided mesendoderm movement, suggesting an in vivo role for HSPGs in mediating the interaction between PDGF-AA and fibronectin.

Energy restriction increases stress resistance and lifespan in Drosophila melanogaster and other species. The roles of individual nutrients in stress resistance and longevity are largely unknown. The vitamin biotin is a potential candidate for mediating these effects, given its known roles in stress signaling and gene regulation by epigenetic mechanisms, i.e. biotinylation of histones. Here, we tested the hypothesis that prolonged culture of Drosophila on biotin-deficient (BD) medium increases stress resistance and lifespan. Flies were fed a BD diet for multiple generations; controls were fed a biotin-normal diet. In some experiments, a third group of flies was fed a BD diet for 12 generations and then switched to control diets for 2 generations to eliminate potential effects of short-term biotin deficiency. Flies fed a BD diet exhibited a 30% increase in lifespan. This increase was associated with enhanced resistance to the DNA-damaging agent hydroxyurea and heat stress. Also, fertility increased significantly compared with biotin-normal controls. Biotinylation of histones was barely detectable in biotin-deprived flies, suggesting that epigenetic events might have contributed to effects of biotin deprivation.

Summary Zebrafish meltdown ( mlt ) mutants develop cystic expansion of the posterior intestine as a result of stromal invasion of nontransformed epithelial cells. Positional cloning identified zebrafish smooth muscle myosin heavy chain ( myh11 ) as the responsible gene. The mlt mutation constitutively activates the Myh11 ATPase, which disrupts smooth muscle cells surrounding the posterior intestine. Adjacent epithelial cells ectopically express metalloproteinases, integrins, and other genes implicated in human cancer cell invasion. Knockdown and pharmacological inhibition of these genes restores intestinal structure in mlt mutants despite persistent smooth muscle defects. These data identify an essential role for smooth muscle signaling in the maintenance of epithelial architecture and support gene expression analyses and other studies that identify a role for stromal genes in cancer cell invasion. Furthermore, they suggest that high-throughput screens to identify regulators of cancer cell invasion may be feasible in zebrafish.

Intestinal development in amniotes is driven by interactions between progenitor cells derived from the three primary germ layers. Genetic analyses and gene targeting experiments in zebrafish offer a novel approach to dissect such interactions at a molecular level. Here we show that intestinal anatomy and architecture in zebrafish closely resembles the anatomy and architecture of the mammalian small intestine. The zebrafish intestine is regionalized and the various segments can be identified by epithelial markers whose expression is already segregated at the onset of intestinal differentiation. Differentiation of cells derived from the three primary germ layers begins more or less contemporaneously, and is preceded by a stage in which there is rapid cell proliferation and maturation of epithelial cell polarization. Analysis of zebrafish mutants with altered epithelial survival reveals that seemingly related single gene defects have different effects on epithelial differentiation and smooth muscle and enteric nervous system development.

Infection with Babesia microti has not been well-described in eastern Pennsylvania, USA, despite the vector of this organism being prevalent. We report 3 cases of babesiosis in eastern Pennsylvania in persons without recent travel outside the region or history of blood transfusions, suggesting emergence of this infection.

There is growing evidence that activity during pregnancy is beneficial for mother and baby; however, less than half of pregnant women meet guidelines for exercise during pregnancy. Objective: In order to improve the health of women and children, we need a better understanding of the barriers to women participating in activities during pregnancy. Therefore, our aim was to determine women’s perceived barriers to physical activity during gestation. We hypothesize that most women either do not know exercise is safe during pregnancy or women do not know what specifically is safe to do during pregnancy. Methods: A 16-item questionnaire was placed in several Ob/Gyn clinics in the Kansas City area. Respondents were women between 18 and 40 years of age who were pregnant or had recently delivered and had no pregnancy complications. Results: Respondents varied in age, BMI, marital status, pregnancies, ethnicity, education, healthcare insurance, and annual household income. We were able to analyze data from 201 surveys. Most participants (97%) perceived their health as good to excellent; yet, 50% were overweight or obese. The most common reason given for women choosing not exercise during pregnancy was lack of time, dislike of exercise, unsure why, and not knowing what to do. However, women who did not exercise spent significantly less time than exercisers doing sedentary and daily living activities than women who exercised while pregnant. If women exercised before pregnancy, then they were 4.5 times more likely to continue during pregnancy. If their health care provider talked about exercise during pregnancy, then women were 7.5 times more likely to continue exercise during gestation. Conclusions: We found that most women are unsure about exercise during pregnancy or do not know what to do during pregnancy. Although most women feel they do not have time to exercise during pregnancy, nonexercisers spent less time doing daily activities compared to exercisers. Most importantly, women were almost 8 times more likely to exercise if this topic was discussed by their obstetric provider. To increase the number of women exercising while pregnant, future studies should aim at efficient ways to discuss and encourage women to follow the recommended guidelines of safe exercises while pregnant.

Public school policies related to physical activity and nutrition recently have become the focal point for policymakers to evaluate the effect of regulations on the childhood obesity epidemic. State school board associations have begun to provide school districts templates for wellness policies, and little research exists that evaluates the effect of a template on the strength and comprehensiveness of these policies.To determine the strength and comprehensiveness of school wellness policies developed using a standard template when compared to those that do not.In 2011, a random sample of wellness policies from school districts in Virginia (ten locally developed wellness policies and ten template-based policies) was coded using a previously validated audit tool for strength and comprehensiveness. Data were reduced to a scale ranging from 0 to 1, with higher scores representing stronger and more-comprehensive policies, and compared using t-tests.Overall, only 17% of school wellness policies met all federal requirements. On average, locally developed policies met five of six federal requirements, whereas VSBA policies met four of six, t(2, 21)=2.161, p0.05. Both types of policies were ranked on a scale from 0 (weakest) to 1 (strongest); both types were weak (M=0.16±0.13) and only mildly comprehensive (M=0.37±0.16). There was a difference in policy comprehensiveness and strength between locally developed policies and template-based policies. Locally developed policies were stronger, t(2, 21)= -1.82, p0.05, and more comprehensive, t(2, 21)= -2.5, p0.05, than template-based policies.In this sample, locally developed policies were stronger than template-based policies. If replicated in large studies, these findings suggest that further research is needed about how best to support schools that wish to develop school wellness policies.

Growth factors regulate a diverse array of cellular functions including proliferation, survival and movement, and the ability to do this often involves interactions with the extracellular matrix (ECM) and particularly heparan sulfate proteoglycans (HSPGs). HSPGs have been shown to sequester growth factors and to act as growth factor co-receptors or receptors themselves. Recent studies, however, have revealed a new role for HSPGs in mediating the interactions of growth factors with the ECM. Specifically, heparan sulfate has been shown to modulate fibronectin structure to reveal previously masked growth factor binding sites. In vivo, this mechanism appears to control the guidance of migrating cells during embryonic development as HSPG-modification of fibronectin enables direct platelet derived growth factor-fibronectin interactions necessary for this process. A model based on this observation is discussed here as well as the possibility that other growth factors/morphogens utilize similar mechanisms involving fibronectin or additional ECM proteins.

Caloric restriction increases stress resistance and lifespan in Drosophila melanogaster and other species. The roles of individual nutrients in stress resistance and longevity are largely unknown. The vitamin biotin is a potential candidate for mediating these effects, given its known roles in stress signaling and gene regulation by epigenetic mechanisms, i.e., biotinylation of histones. Here, we tested the hypothesis that prolonged culture of Drosophila on biotin-deficient medium increases stress resistance and lifespan. Flies were fed a biotin-deficient diet for multiple generations; controls were fed a biotin-normal diet. In some experiments, a third group of flies was fed a biotin-deficient diet for 12 generations and then switched to control diets for two generations to eliminate potential effects of short-term biotin deficiency. Flies fed a biotin-deficient diet exhibited a 30% increase in lifespan. This increase was associated with enhanced resistance to the DNA-damaging agent hydroxyurea and heat stress. Also, fertility increased significantly compared with biotin-normal controls. Biotinylation of histones was barely detectable in biotin-deprived flies, suggesting that epigenetic events might have contributed to effects of biotin deprivation.

Collagen production plays a significant role in tumor development, especially in breast cancer, hepatocarcinomas, and colorectal carcinoma. However, collagen production is decreased during oncogenic transformation of cells in culture. This study demonstrates that methylation of the collagen alpha2(I) gene transcription start site occurs frequently in human cancer cell lines (9 of 10), including breast cancer cell lines (MCF-7 and Hs578T), hepatocellular carcinoma cell lines (SNU387, SNU449, SNU398, and PLC/PRF/5), a fibrosarcoma cell line (HT1080), and colorectal carcinoma cell lines (HCT116, SW480, and SW620). In addition, the collagen gene is more methylated in colorectal cancer tissues compared with normal mucosa. The increased DNA methylation of the collagen gene in cell lines is inversely correlated with collagen mRNA steady-state levels. Most importantly, treatment of fibrosarcoma or breast carcinoma cells with a DNA methyltransferase inhibitor, 5-aza-2'-deoxycytidine, resulted in lower methylation and reactivation of the collagen gene in a dose-responsive manner. This is the first demonstration that the collagen alpha2(I) gene is methylated in multiple cancer cell lines correlating with loss of collagen expression and also methylated in primary cancer tissues. These data also suggest that methylation-induced repression of collagen transcription may be a frequent occurrence in cancer.

Glioblastomas are the most common and lethal cancer in the central nervous system. Comprehensive genetic studies showed that in high-grade gliomas, overexpression of platelet-derived growth factor receptor alpha (PDGFRα) ranks third among top amplified genes and frequently co-occurs with loss of tumor suppressor genes, p16/INK4a and p14/ARF (p19/ARF in mice), in these high-grade glioblastomas. However, the biological consequences of PDGFRα overexpression in INK4a/ARF-deficient glial cells and glioma cells remain elusive. Here we show that activation of PDGFRα signaling by overexpressing PDGFRα and/or PDGF-A transformed Ink4a/Arf-deficient mouse astrocytes in vitro and rendered these cells highly tumorigenic in the brain of mice. Consistently, in INK4a/ARF null but not wild-type human glioma cell lines that express endogenous PDGFRα, overexpression of PDGF-A significantly enhances glioma formation in the brain. Re-introduction of p16/INK4a into Ink4a/Arf-null astrocytes suppressed PDGFRα-induced cell transformation in vitro and glioma formation in the brain. Conversely, cellular depletion of endogenous p16/INK4a by RNA interference in human glioma cells markedly enhances colony formation in vitro when compared to the controls. Mechanistically, abrogation of intrinsic tyrosine kinase activity of PDGFRα or interruptions of signaling modules at PDGFRα (Y to F mutations at specific tyrosine residues) that lost binding capacity for PI3K or Shp-2, but not PLC gamma or c-Src, significantly diminished PDGFRα-induced glioma formation in the brain. In vitro, specific YF mutations or inhibitors of PI3K or Shp-2 attenuated Akt activation and PDGFRα-induced colony formation. Furthermore, inhibition of Shp-2 by its inhibitors and siRNAs disrupts the interaction of PI3K with PDGFRα that is critical for gliomagenesis of Ink4a/Arf null cells. In summary, our data suggests that activation of PDGFRα signaling, particularly through the PI3K and Shp-2 pathways, in INK4a/ARF deficient astrocytes and glioma cells induce gliomagenesis in the brain. Our findings provide critical insights into interactions of genetic lesions frequently found in clinical glioma specimens and will be useful for identification of new therapeutic targets for treatments of patients with malignant gliomas. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3124.