2,937 research outputs found
Early exposure to environmental toxin contributes to neuronal vulnerability and axonal pathology in a model of familial ALS
Adult onset amyotrophic lateral sclerosis (ALS) arises due to progressive and irreversible functional deficits to the central nervous system, specifically the loss of motor neurons. Sporadic ALS causality is not well understood, but is almost certainly of multifactorial origin involving a combination of genetic and environmental factors. The discovery of endemic ALS in the native Chamorro population of Guam during the 1950s and the co-occurrence of parkinsonism and dementia in some patients led to searches for an environmental toxins that could be responsible. In the present paper, we report that an environmental neurotoxin enhances mutant superoxide dismutase (SOD)-induced spinal motor neuron death and pathology and induces motor axon abnormalities. These results cumulatively confirm earlier findings that exposure to an environmental toxin is sufficient to produce the disease phenotype and indicate a role for gene-environment interaction in some forms of the disease
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Diagnostically significant antigens of <i>Treponema pallidum</i> subsp. <i>pallidum</i>: identification, serological efficacy, and characterisation of the major antigenic determinants.
The antibody response to native antigens derived from Treponema pallidum (Nichols strain) was investigated by western blotting. In early primary disease the responses were most frequently to the major immunodominant antigen, TpN47, and the flagellar proteins. Strong responses to several other lipoproteins, especially TpN44.5, TpN17 and TpN15, were observed in all other disease stages. Generally, this confirmed the importance of TpN47, TpN44.5, TpN17, and TpN15 as diagnostlcally significant antigen. Western blot analysis using recombinant proteins showed the four major lipoproteins, TpN47, TpN44.5, TpN17, and TpN15, to be important disease specific antigens, with TpN47 particularly reactive in early primary infections. TpN24-28 was found to be disease specific but only reactive with relatively few strongly positive sera, and so of relatively little diagnostic significance. Further analysis of the other recombinant proteins by enzyme immunoassay confirmed them as important diagnostic antigens, but no single recombinant protein was capable of detecting all cases of serologically confirmed syphilis. However, an enzyme immunoassay using a solid phase coated with a combination of all four major lipoproteins proved highly specific and showed improved sensitivity over a commercially available enzyme immunoassay based on native antigens. Synthetic peptide epitope mapping studies of the four major lipoproteins showed that the antigenic sequences within these proteins were not simple linear epitopes. The complicated picture of several reactive regions across the proteins, each containing multiple epitopes, was typical of the type of responses seen when a substantial part of the antibody response is directed towards conformational epitopes. Further analysis of the epitopes present within the four major lipoproteins using phage display isolated several long protein sequences which represented high affinity antibody binding motifs. The size of the sequences suggests that the retention by the solid phase is due either to conformational epitopes, or to a mixture of epitope types producing high affinity binding through multipoint attachment. The sequences identified have potential as antigens for use in diagnostic tests
Adhesive and mechanical regulation of mesenchymal stem cell differentiation in human bone marrow and periosteum-derived progenitor cells
It has previously been demonstrated that cell shape can influence commitment of human bone marrow-derived mesenchymal stem cells (hBMCs) to adipogenic, osteogenic, chondrogenic, and other lineages. Human periosteum-derived cells (hPDCs) exhibit multipotency similar to hBMCs, but hPDCs may offer enhanced potential for osteogenesis and chondrogenesis given their apparent endogenous role in bone and cartilage repair in vivo. Here, we examined whether hPDC differentiation is regulated by adhesive and mechanical cues comparable to that reported for hBMC differentiation. When cultured in the appropriate induction media, hPDCs at high cell seeding density demonstrated enhanced levels of adipogenic or chondrogenic markers as compared with hPDCs at low cell seeding density. Cell seeding density correlated inversely with projected area of cell spreading, and directly limiting cell spreading with micropatterned substrates promoted adipogenesis or chondrogenesis while substrates promoting cell spreading supported osteogenesis. Interestingly, cell seeding density influenced differentiation through both changes in cell shape and non-shape-mediated effects: density-dependent adipogenesis and chondrogenesis were regulated primarily by cell shape whereas non-shape effects strongly influenced osteogenic potential. Inhibition of cytoskeletal contractility by adding the Rho kinase inhibitor Y27632 further enhanced adipogenic differentiation and discouraged osteogenic differentiation of hPDCs. Together, our results suggest that multipotent lineage decisions of hPDCs are impacted by cell adhesive and mechanical cues, though to different extents than hBMCs. Thus, future studies of hPDCs and other primary stem cell populations with clinical potential should consider varying biophysical metrics for more thorough optimization of stem cell differentiation.R01 EB000262 - NIBIB NIH HHS; R01 GM060692 - NIGMS NIH HHSPublished versio
Nonprofit Georgia: Geography
This pamphlet summarizes statistics on the nonprofit sector in Georgia, assembled and analyzed by a Nonprofit Studies Program research team. The focus of this second report in the "Nonprofit Georgia" series is the geographic distribution of Georgia's nonprofit resources. Numerous tables and exhibits report on the distribution of public charities and foundations by geographic area, and compare this to the distribution of population and income in the state. Public support and government grants to charities are analyzed by geographic region, as is the geographic distribution of grants by Georgia foundations. Analysis is based primarily on 990 and 990-PF forms filed by Georgia public charities and foundations in 2000 and 2005. This report is a part of ongoing research on public charities and foundations in the state of Georgia, made possible through a generous grant from the Wilbur and Hilda Glenn Family Foundation. Research Report Number 07-0
EFFECT OF THE REPLACEMENT OF MAIZE WITH WHEAT OFFAL IN BROILER FINISHER DIETS ON GROWTH PERFORMANCE AND FEED COST
An experiment was carried out to assess the effect of replacing maize with wheat offal in broiler finisher diets on bird performance and feed cost. Six rations were formulated using 0, 5, 10, 15, 20, and 25 percent wheat offal to replace maize in the rations. The formulated rations were fed to one hundred and fifty six commercial broiler finisher birds in a completely randomized experimental design. All the rations were made isocaloric and isonitrogenous with the inclusion of varying levels of palm oil. The results indicated that there were no significant differences (P > 0.05) in body weight, body weight gain, feed intake and efficiency of feed utilization and carcass characteristics amongst the treatment means. However, wheat offal
replaced maize for up to 25 percent without any adverse effect on performance. More so, at 25 percent inclusion to replace maize, cost of feed per kilogram was reduced by about 15.91 percent. Such feed cost reduction could engender overall production cost reduction in broiler production especially at the finisher stage
Press-pulse odocoileus Virginianus herbivory in relict tsuga canadensis stands in the Western Upper Peninsula of Michigan, USA
Ungulate herbivory occurring within a forest plant community’s natural range of variation may help maintain species diversity. However, acute or chronically elevated levels of herbivory can produce dramatic changes in forest communities. For example, chronically high levels of herbivory by white-tailed deer (Odocoileus virginianus Zimmerman) in regions of historically low abundance at northern latitudes have dramatically altered forest community composition. In eastern hemlock (Tsuga canadensis L. Carrière) stands where deer aggregate during winter, high deer use has been associated with a shift towards deciduous species (i.e., maples [Acer spp.]) dominating the regeneration layer. Especially harsh winters can lead to deer population declines, which could facilitate regeneration of species that have been suppressed by browsing, such as hemlock. To enhance our understanding of how fluctuations in herbivory influence regeneration dynamics, we surveyed regeneration and deer use in 15 relict hemlock stands in the western Upper Peninsula of Michigan in 2007 and again in 2015. With the exception of small seedlings (0.04–0.24 m height), primarily maples whose abundance increased significantly (p \u3c 0.05), we observed widespread significant declines (p \u3c 0.05) in the abundance of medium (0.25 ≤ 1.4 m height) and large regeneration (\u3e1.4 m tall ≤ 4 cm diameter at breast height) over the study period. Midway through our study period, the region experienced a high severity winter (i.e., “polar vortex”) which resulted in a substantial decline in the white-tailed deer population. Given the dominance of maples and dearth of hemlock in the seedling layer, the decline in the deer population may fail to forestall or possibly hasten the trend towards maple dominance of the regeneration layer as these stands recover from pulses of acute herbivory associated with high-severity winters and the press of chronically high herbivory that precedes them
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Controlled release nanoparticulate matter delivery system
A controlled release nanoparticulate matter delivery system includes a plurality of thermoresponsive modules containing a respective nanoparticulate matter. Each thermoresponsive module is selectively operable in at least one of a heating mode that releases the nanoparticulate matter and a cooling mode that inhibits release of the nanoparticulate matter. A control module is in electrical communication with the plurality of thermoresponsive modules. The control module is configured to determine a temperature of each thermoresponsive module and to select the at least one heating mode and cooling mode based on the temperature. The heating and cooling mode may be selected in response to a desired dosing profile and/or a biometric condition.Board of Regents, University of Texas Syste
The Influence of Dose of a Plant-Derived Volatile Cue on Arabidopsis thaliana Resistance against Insect Herbivores
Green leaf volatiles (GLVs) are plant-derived volatile organic compounds (VOCs) known to affect plant-plant communication. Specifically, GLVs can facilitate “priming”, whereby plants initiate a faster and stronger defensive response to a subsequent stress. The stress-induced GLV cis-3-hexenyl acetate (z3HAC) is a known priming cue, yet whether the concentration of the z3HAC affects plant defenses is unknown. Here, we tested the hypothesis that z3HAC concentration of would influence Arabidopsis thaliana resistance against a specialist (Trichoplusia ni) and generalist (Spodoptera exigua) herbivore. Our z3HAC treatments ranged from 0-100 ng/hr, which spanned the range of recorded natural emissions (10-40 ng/hr). We measured relative growth rates (RGR) of naïve caterpillars as a proxy for plant resistance. z3HAC concentration had no linear effects on A. thaliana resistance, even though the specialist performed better than did the generalist. Interestingly, the specialist’s RGR was greater than the generalist’s RGR on previously induced plants independent of z3HAC. Our results suggest that the concentration of z3HAC may not be an important factor in its reliability as a predictor of future herbivory
Assessing Positive and Mixed Emotions Related to Racial Experiences on Campus
As the climate of a university can impact the experiences and mental health of students, faculty, and staff (Budge et al., 2020), it is necessary to devote attention to race-related experiences that contribute to and perpetuate a university’s racial climate. Past psychological research has focused on reducing negative emotional reactions to negative race-related experiences (Carter & Forsyth, 2020; Kim, 2016). Although this line of research is critical to improving the experiences of people of color, there is another avenue for improvement that is often neglected: increasing positive race-related experiences. Identifying positive and quasi-positive experiences among racial groups will help us understand how students, faculty, and staff perceive the on-campus racial climate at Kennesaw State University. Data was collected from KSU students, faculty, and staff who participated in focus groups, of 3-12 participants. During the interview, a facilitator invited participants to share their race-related experiences on-campus and in the community and emotional reactions. Another researcher took notes on participants’ responses. Sessions were conducted virtually through Collaborate Ultra for an hour, and, at the end of each session, additional resources were offered for support and counseling if needed. This data will be analyzed using thematic analysis is in progress. Racial experiences will be coded as either positive, negative, or mixed. Participant emotions will also be coded, first for content, then for positivity or negativity. Faculty/staff and student responses will be compared with respect to types of positive and mixed experiences, and the emotional reactions to these experiences. The results will be presented to upper-level KSU administration to inform awareness of the present state of KSU’s racial climate and future university-wide efforts to improve race relations. We also hope this research will both advance theoretical understanding of the relationship between racial experiences and emotional reactions and encourage other universities to undertake similar projects
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