36 research outputs found
Exploring the Impact of Applicantsâ Gender and Religion on Principalsâ Screening Decisions for Assistant Principal Applicants
In this experimental study, a national random sample of high school principals (stratified by gender) were asked to evaluate hypothetical applicants whose resumes varied by religion (Jewish, Catholic, nondenominational) and gender (male, female) for employment as assistant principals. Results reveal that male principals rate all applicants higher than female principals and that the gender and religion of applicants failed to negatively or positively affect principalsâ evaluations. These results suggest that discrimination based on an applicantâs gender and religion failed to be manifested during the pre-interview stage of the selection process. The paper concludes with a theoretical discussion of the distinction between explicit and implicit prejudice, and encourages future researchers to investigate the potential impact of prejudice on employment selection decisions and to consider whether schools should promote diversity in leadership positions
Promise or Peril: Reframing Parental Rights in Special Education Through School Choice Reform Initiatives
While several court rulings have recognized parental rights over education to varying degrees, the emergence of a common public school agenda has led to an increasing establishment of barriers limiting opportunities for parents to exercise their rights and control over the upbringing of their children via school choice initiatives. Parental rights and the exercise of choice are further complicated and restricted for parents of students with disabilities. Although the right to an education is protected under the Individuals with Disabilities in Education Act (IDEA), parental choice is recast as parental participation in the educational decisions affecting children with disabilities. In other words, parents of students with disabilities have no meaningful choice and can exercise extremely limited control over the education and upbringing of their children if they want to enjoy the protections afforded under the IDEA. Part I of this note examines the parental rights doctrine emerging from the U.S. Supreme Court and describes the historical perspectives on child development and educational interests that also factor into the discussion about parental rights over education. The limits on parental rights and control are analyzed in Part II, with specific attention on statesâ legal effortsâthrough constitutional and statutory provisionsâto replace parental control over education and upbringing with state control. Part III examines the federal disability laws that apply specifically to protect the rights of students with disabilities as well as the rights of their parents or guardians. Part III also addresses the concerns of school choice opponents who assert the need for limits on state-supported choice initiatives given the perceived negative impacts of such programs on public education. Part IV summarizes the promises and perils of special education voucher programs (SVPs), which are often described as an emerging educational reform movement that seeks to expand school choice options for parents of students with disabilities and identifies the need for legislative reform of the IDEA. Finally, the Conclusion offers concluding remarks and recommends expansion of the choice debate in order to reflect a continuum perspective of educational placements that empower parents of students with disabilities to preserve their familyâs values and beliefs while also securing a high-quality education for their children
Sialylation of campylobacter jejuni lipo-oligosaccharides: impact on phagocytosis and cytokine production in mice
<p>Background:
Guillain-Barré syndrome (GBS) is a post-infectious polyradiculoneuropathy, frequently associated with antecedent Campylobacter jejuni (C. jejuni) infection. The presence of sialic acid on C. jejuni lipo-oligosaccharide (LOS) is considered a risk factor for development of GBS as it crucially determines the structural homology between LOS and gangliosides, explaining the induction of cross-reactive neurotoxic antibodies. Sialylated C. jejuni are recognised by TLR4 and sialoadhesin; however, the functional implications of these interactions in vivo are unknown.</p>
<p>Methodology/Principal Findings:
In this study we investigated the effects of bacterial sialylation on phagocytosis and cytokine secretion by mouse myeloid cells in vitro and in vivo. Using fluorescently labelled GM1a/GD1a ganglioside-mimicking C. jejuni strains and corresponding (Cst-II-mutant) control strains lacking sialic acid, we show that sialylated C. jejuni was more efficiently phagocytosed in vitro by BM-MΊ, but not by BM-DC. In addition, LOS sialylation increased the production of IL-10, IL-6 and IFN-ÎČ by both BM-MΊ and BM-DC. Subsequent in vivo experiments revealed that sialylation augmented the deposition of fluorescent bacteria in splenic DC, but not macrophages. In addition, sialylation significantly amplified the production of type I interferons, which was independent of pDC.</p>
<p>Conclusions/Significance:
These results identify novel immune stimulatory effects of C. jejuni sialylation, which may be important in inducing cross-reactive humoral responses that cause GBS</p>
Upregulation of α7 Nicotinic Receptors by Acetylcholinesterase C-Terminal Peptides
BACKGROUND: The alpha-7 nicotinic acetylcholine receptor (alpha7-nAChR) is well known as a potent calcium ionophore that, in the brain, has been implicated in excitotoxicity and hence in the underlying mechanisms of neurodegenerative disorders such as Alzheimer's disease. Previous research implied that the activity of this receptor may be modified by exposure to a peptide fragment derived from the C-terminal region of the enzyme acetylcholinesterase. This investigation was undertaken to determine if the functional changes observed could be attributed to peptide binding interaction with the alpha7-nAChR, or peptide modulation of receptor expression. METHODOLOGY/PRINCIPAL FINDINGS: This study provides evidence that two peptides derived from the C-terminus of acetylcholinesterase, not only selectively displace specific bungarotoxin binding at the alpha7-nAChR, but also alter receptor binding properties for its familiar ligands, including the alternative endogenous agonist choline. Of more long-term significance, these peptides also induce upregulation of alpha7-nAChR mRNA and protein expression, as well as enhancing receptor trafficking to the plasma membrane. CONCLUSIONS/SIGNIFICANCE: The results reported here demonstrate a hitherto unknown relationship between the alpha7-nAChR and the non-enzymatic functions of acetylcholinesterase, mediated independently by its C-terminal domain. Such an interaction may prove valuable as a pharmacological tool, prompting new approaches for understanding, and combating, the process of neurodegeneration
Upregulation of α7 Nicotinic Receptors by Acetylcholinesterase C-Terminal Peptides
BACKGROUND: The alpha-7 nicotinic acetylcholine receptor (alpha7-nAChR) is well known as a potent calcium ionophore that, in the brain, has been implicated in excitotoxicity and hence in the underlying mechanisms of neurodegenerative disorders such as Alzheimer's disease. Previous research implied that the activity of this receptor may be modified by exposure to a peptide fragment derived from the C-terminal region of the enzyme acetylcholinesterase. This investigation was undertaken to determine if the functional changes observed could be attributed to peptide binding interaction with the alpha7-nAChR, or peptide modulation of receptor expression. METHODOLOGY/PRINCIPAL FINDINGS: This study provides evidence that two peptides derived from the C-terminus of acetylcholinesterase, not only selectively displace specific bungarotoxin binding at the alpha7-nAChR, but also alter receptor binding properties for its familiar ligands, including the alternative endogenous agonist choline. Of more long-term significance, these peptides also induce upregulation of alpha7-nAChR mRNA and protein expression, as well as enhancing receptor trafficking to the plasma membrane. CONCLUSIONS/SIGNIFICANCE: The results reported here demonstrate a hitherto unknown relationship between the alpha7-nAChR and the non-enzymatic functions of acetylcholinesterase, mediated independently by its C-terminal domain. Such an interaction may prove valuable as a pharmacological tool, prompting new approaches for understanding, and combating, the process of neurodegeneration
The genomic landscape of balanced cytogenetic abnormalities associated with human congenital anomalies
Despite the clinical significance of balanced chromosomal abnormalities (BCAs), their characterization has largely been restricted to cytogenetic resolution. We explored the landscape of BCAs at nucleotide resolution in 273 subjects with a spectrum of congenital anomalies. Whole-genome sequencing revised 93% of karyotypes and demonstrated complexity that was cryptic to karyotyping in 21% of BCAs, highlighting the limitations of conventional cytogenetic approaches. At least 33.9% of BCAs resulted in gene disruption that likely contributed to the developmental phenotype, 5.2% were associated with pathogenic genomic imbalances, and 7.3% disrupted topologically associated domains (TADs) encompassing known syndromic loci. Remarkably, BCA breakpoints in eight subjects altered a single TAD encompassing MEF2C, a known driver of 5q14.3 microdeletion syndrome, resulting in decreased MEF2C expression. We propose that sequence-level resolution dramatically improves prediction of clinical outcomes for balanced rearrangements and provides insight into new pathogenic mechanisms, such as altered regulation due to changes in chromosome topology
Robust estimation of bacterial cell count from optical density
Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data