5,461 research outputs found
Characterization of Murine Breast Cancer Cell Lines for Anti-Cancer Vaccine
Breast cancer is the most commonly diagnosed cancer in women and the second leading cause of cancer death among women in the United States (1). While treatments involving radiation and chemotherapy currently exist, disease must be detected early in order for the treatments to be somewhat effective, and there is no effective treatment after metastasis occurs (2). Additionally, current therapies do not mitigate tumor immunosuppression. Decreasing the tumor-associated immunosuppressive conditions while activating antitumor immunity could prevent recurrence and metastasis, possibly leading to an effective treatment for cancer (3). Tumor cell vaccines could possibly address this issue and have become a recent topic of research. They have the potential to generate tumor regression and antitumor immune responses, but they have had low clinical response rates and poor immunogenicity so far (3, 4).
We suspect the failure of cancer vaccines to be due to the immunosuppression and heterogeneity of breast cancers. Thus, to determine how and why different breast cancers induce different levels of immunosuppression, we studied different cancer cell lines of varying levels of immunogenicity. The study included five murine breast cancer cell lines, 4T1, 4T07, 66cl4, 168FARN, and 67NR. These are sister cell lines that were isolated from a Balb/cfC3H mouse and that differ in aggressiveness and metastatic capability. The production of immunosuppressive cytokines GM-CSF, G-CSF, M-CSF, IL-6, MCP-1, TGF-β, and VEGF was quantified for each of these cell lines. We also studied the effect these cytokines have on the expansion of myeloid-derived suppressor cells (MDSCs), which are known to suppress the immune response, and found that high levels of G-CSF are correlated with high numbers of MDSCs. A correlation between G-CSF levels and MDSC accumulation in these breast cancer cell lines could lead to future studies in which the effects of G-CSF are blocked in order to develop effective autologous breast cancer vaccines
An earnings-return model for strategic market planning / BEBR No. 869
Includes bibliographical references (p. 38-39).Few models currently exist which aid managers in their strategic market planning. The models or frameworks which do exist have a variety of shortcomings, a major one being an inadequate linkage to a business organization's dominant goals for existence -- earnings and return on investment. This paper develops a planning model based on a firm's present levels of earnings and return designed to provide a partial foundation on which its managers can base their strategic market planning. Depending upon the firm's placement in the model, different organizational objectives and strategies exist for improving future performance
Satellite applications to marine geodesy
Potential use of satellites for enhancing positioning capabilities and for marine geodetic contro
An Engineered Glutamate-gated Chloride (GluCl) Channel for Sensitive, Consistent Neuronal Silencing by Ivermectin
A modified invertebrate glutamate-gated Cl− channel (GluCl αβ) was previously employed to allow pharmacologically induced silencing of electrical activity in CNS neurons upon exposure to the anthelmintic drug ivermectin (IVM). Usefulness of the previous receptor was limited by 1) the high concentration of IVM necessary to elicit a consistent silencing phenotype, raising concern about potential side effects, and 2) the variable extent of neuronal spike suppression, due to variations in the co-expression levels of the fluorescent protein-tagged α and β subunits. To address these issues, mutant receptors generated via rational protein engineering strategies were examined for improvement. Introduction of a gain-of-function mutation (L9′F) in the second transmembrane domain of the α subunit appears to facilitate β subunit incorporation and substantially increase heteromeric GluCl αβ sensitivity to IVM. Removal of an arginine-based endoplasmic reticulum retention motif (RSR mutated to AAA) from the intracellular loop of the β subunit further promotes heteromeric expression at the plasma membrane possibly by preventing endoplasmic reticulum-associated degradation of the β subunit rather than simply reducing endoplasmic reticulum retention. A monomeric XFP (mXFP) mutation that prevents fluorescent protein dimerization complements the mutant channel effects. Expression of the newly engineered GluCl opt α-mXFP L9′F + opt β-mXFP Y182F RSR_AAA receptor in dissociated neuronal cultures markedly increases conductance and reduces variability in spike suppression at 1 nm IVM. This receptor, named “GluClv2.0,” is an improved tool for IVM-induced silencing
Apollo Lightcraft Project
This second year of the NASA/USRA-sponsored Advanced Aeronautical Design effort focused on systems integration and analysis of the Apollo Lightcraft. This beam-powered, single-stage-to-orbit vehicle is envisioned as the shuttlecraft of the 21st century. The five person vehicle was inspired largely by the Apollo Command Module, then reconfigured to include a new front seat with dual cockpit controls for the pilot and co-pilot, while still retaining the 3-abreast crew accommodations in the rear seat. The gross liftoff mass is 5550 kg, of which 500 kg is the payload and 300 kg is the LH2 propellant. The round trip cost to orbit is projected to be three orders of magnitude lower than the current space shuttle orbiter. The advanced laser-driven 5-speed combined-cycle engine has shiftpoints at Mach 1, 5, 11 and 25+. The Apollo Lightcraft can climb into low Earth orbit in three minutes, or fly to any spot on the globe in less than 45 minutes. Detailed investigations of the Apollo Lightcraft Project this second year further evolved the propulsion system design, while focusing on the following areas: (1) man/machine interface; (2) flight control systems; (3) power beaming system architecture; (4) re-entry aerodynamics; (5) shroud structural dynamics; and (6) optimal trajectory analysis. The principal new findings are documented. Advanced design efforts for the next academic year (1988/1989) will center on a one meter+ diameter spacecraft: the Lightcraft Technology Demonstrator (LTD). Detailed engineering design and analyses, as well as critical proof-of-concept experiments, will be carried out on this small, near-term machine. As presently conceived, the LTD could be constructed using state of the art components derived from existing liquid chemical rocket engine technology, advanced composite materials, and high power laser optics
Quantitative autism symptom patterns recapitulate differential mechanisms of genetic transmission in single and multiple incidence families
Abstract Background Previous studies have demonstrated aggregation of autistic traits in undiagnosed family members of children with autism spectrum disorder (ASD), which has significant implications for ASD risk in their offspring. This study capitalizes upon a large, quantitatively characterized clinical-epidemiologic family sample to establish the extent to which family transmission pattern and sex modulate ASD trait aggregation. Methods Data were analyzed from 5515 siblings (2657 non-ASD and 2858 ASD) included in the Interactive Autism Network. Autism symptom levels were measured using the Social Responsiveness Scale (SRS) and by computing Diagnostic and Statistical Manual of Mental Disorders—Fifth Edition (DSM-5) symptom scores based on items from the SRS and Social Communication Questionnaire. Generalized estimating equation models evaluated the influence of family incidence types (single versus multiple incidence families; male-only ASD-affected families versus families with female ASD-affected children), diagnostic group (non-ASD children with and without a history of language delay with autistic speech and ASD-affected children), and sibling sex on ASD symptom levels. Results Non-ASD children manifested elevated ASD symptom burden when they were members of multiple incidence families—this effect was accentuated for male children in female ASD-containing families—or when they had a history of language delay with autistic qualities of speech. In this sample, ASD-affected children from multiple incidence families had lower symptom levels than their counterparts in single incidence families. Recurrence risk for ASD was higher for children from female ASD-containing families than for children from male-only families. Conclusions Sex and patterns of family transmission modulate the risk of autism symptom burden in undiagnosed siblings of ASD-affected children. Identification of these symptoms/traits and their molecular genetic causes may have significant implications for genetic counseling and for understanding inherited liabilities that confer risk for ASD in successive generations. Autism symptom elevations were more dramatic in non-ASD children from multiple incidence families and those with a history of language delay and autistic qualities of speech, identifying sub-groups at substantially greater transmission risk. Higher symptom burden and greater recurrence in children from female ASD-containing families indicate that familial aggregation patterns are further qualified by sex-specific thresholds, supportive of the notion that females require a higher burden of deleterious liability to cross into categorical ASD diagnosis
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