2,289 research outputs found
The Effects of Palmitate on the Expression of G-protein Coupled Receptors and GLUT Transporters in Neuro2A Cells
Palmitate (PA) is a saturated fatty acid that has been reported to be elevated in individuals with metabolic syndromes. The effects of fatty acids on the expression of various fatty acid receptors on neuronal cells is unknown, as is the effects of fatty acids on GLUT transporters. In this study, Neuro-2a (N2a) cells were treated with either 300μM of bovine serum albumin (BSA) or 300μM of palmitate conjugated to BSA (PA) at various time points to determine the effect of palmitate on the expression of various fatty acid receptors and GLUT transporters. RNA isolation followed by RT-PCR with primers specific to various G- protein coupled receptors (GPRs) and GLUT transporters was performed on these treated cells and further analyzed with statistical tests. 24 hour treatment with 300μM PA yielded increased mRNA expression of GPR41, GPR84, GPR119, GPR120 and GLUT5 when compared to vehicle control. In order to determine how GLUT5 may be regulated, N2a cells were treated with 300μM BSA along with PKA inhibitor KT5720 or GPR120 agonist GW9508. RNA isolation followed by RT-PCR showed that GPR41, GPR119 and GLUT5 expression increased with PKA inhibition, and GPR120 expression increased with GPR120 stimulation. These results suggest that PKA may play a role in the regulation of GPR41, GPR119 and GLUT5 in neuronal cells stimulated with palmitate
Resistance to ectromelia virus infection requires cGAS in bone marrow-derived cells which can be bypassed with cGAMP therapy.
Cells sensing infection produce Type I interferons (IFN-I) to stimulate Interferon Stimulated Genes (ISGs) that confer resistance to viruses. During lympho-hematogenous spread of the mouse pathogen ectromelia virus (ECTV), the adaptor STING and the transcription factor IRF7 are required for IFN-I and ISG induction and resistance to ECTV. However, it is unknown which cells sense ECTV and which pathogen recognition receptor (PRR) upstream of STING is required for IFN-I and ISG induction. We found that cyclic-GMP-AMP (cGAMP) synthase (cGAS), a DNA-sensing PRR, is required in bone marrow-derived (BMD) but not in other cells for IFN-I and ISG induction and for resistance to lethal mousepox. Also, local administration of cGAMP, the product of cGAS that activates STING, rescues cGAS but not IRF7 or IFN-I receptor deficient mice from mousepox. Thus, sensing of infection by BMD cells via cGAS and IRF7 is critical for resistance to a lethal viral disease in a natural host
Development of Silica-Immobilized Vaccines for Improving Thermo-Tolerance and Shelf-Life
Introduction. It is estimated that 50% of vaccines produced annu- ally are wasted because effectivity is dependent on protein structure and heat exposure disrupts the intermolecular interactions that maintain this structure. Since 90% of vaccines require a temperature- controlled supply chain, it is necessary to create a cold chain system to minimize vaccine waste. We have developed a more sustainable technology via the adsorption of Invasion Plasmid Antigen D (IpaD) onto mesoporous silica gels, improving the thermal stability of pro- tein-based therapeutics.
Methods.xThe solution depletion method using UV-Vis was uti- lized to study the adsorption of IpaD onto silica gels. The silica-IpaD complex is heated above the denaturing temperature of the protein and then the IpaD is removed using N,N-Dimethyldodecylamine N-oxide (LDAO) and their secondary structure is tested using cir- cular dichroism (CD).
Results. Pore diameter, pore volume and surface area were charac- terized for seven different silica gels. Silica gels designated as 6389, 6378, and 6375 had an adsorption percentage above 95% at pore volumes of 2.2, 2.8 and 3.8 cm3 mg-1, respectively. CD analyses con- firmed that the adsorbed IpaD after the heat treatment displayed a similar “W” shape CD signal as the native IpaD, indicating the con- servation of α-helices. In contrast, the unprotected IpaD after being exposed to high temperature shows a flat CD signal, demonstrating the loss of secondary structure.
Conclusion. We have successfully increased the thermo-tolerance for IpaD using mesoporous silica and continue to further optimize mesoporous silica’s physiochemical properties to improve adsorption and desorption yields
Randomized controlled trial of a coordinated care intervention to improve risk factor control after stroke or transient ischemic attack in the safety net: Secondary stroke prevention by Uniting Community and Chronic care model teams Early to End Disparities (SUCCEED).
BackgroundRecurrent strokes are preventable through awareness and control of risk factors such as hypertension, and through lifestyle changes such as healthier diets, greater physical activity, and smoking cessation. However, vascular risk factor control is frequently poor among stroke survivors, particularly among socio-economically disadvantaged blacks, Latinos and other people of color. The Chronic Care Model (CCM) is an effective framework for multi-component interventions aimed at improving care processes and outcomes for individuals with chronic disease. In addition, community health workers (CHWs) have played an integral role in reducing health disparities; however, their effectiveness in reducing vascular risk among stroke survivors remains unknown. Our objectives are to develop, test, and assess the economic value of a CCM-based intervention using an Advanced Practice Clinician (APC)-CHW team to improve risk factor control after stroke in an under-resourced, racially/ethnically diverse population.Methods/designIn this single-blind randomized controlled trial, 516 adults (≥40 years) with an ischemic stroke, transient ischemic attack or intracerebral hemorrhage within the prior 90 days are being enrolled at five sites within the Los Angeles County safety-net setting and randomized 1:1 to intervention vs usual care. Participants are excluded if they do not speak English, Spanish, Cantonese, Mandarin, or Korean or if they are unable to consent. The intervention includes a minimum of three clinic visits in the healthcare setting, three home visits, and Chronic Disease Self-Management Program group workshops in community venues. The primary outcome is blood pressure (BP) control (systolic BP <130 mmHg) at 1 year. Secondary outcomes include: (1) mean change in systolic BP; (2) control of other vascular risk factors including lipids and hemoglobin A1c, (3) inflammation (C reactive protein [CRP]), (4) medication adherence, (5) lifestyle factors (smoking, diet, and physical activity), (6) estimated relative reduction in risk for recurrent stroke or myocardial infarction (MI), and (7) cost-effectiveness of the intervention versus usual care.DiscussionIf this multi-component interdisciplinary intervention is shown to be effective in improving risk factor control after stroke, it may serve as a model that can be used internationally to reduce race/ethnic and socioeconomic disparities in stroke in resource-constrained settings.Trial registrationClinicalTrials.gov Identifier NCT01763203
The Roles of CD4+ T Cell Help, Sex, and Dose in the Induction of Protective CD8+ T Cells Against a Lethal Poxvirus by mRNA-LNP Vaccines
The role of CD4+ T cells in the induction of protective CD8+ T cells by mRNA lipid nanoparticle (LNP) vaccines is unknown. We used B6 or Tlr9−/− mice depleted or not of CD4+ T cells and LNP vaccines loaded with mRNAs encoding the ectromelia virus (ECTV) MHC class I H-2 Kb-restricted immunodominant CD8+ T cell epitope TSYKFESV (TSYKFESV mRNA-LNPs) or the ECTV EVM158 protein, which contains TSYKFESV (EVM-158 mRNA-LNPs). Following prime and boost with 10 μg of either vaccine, Kb-TSYKFESV-specific CD8+ T cells fully protected male and female mice from ECTV at 29 (both mRNA-LNPs) or 90 days (EVM158 mRNA-LNPs) post boost (dpb) independently of CD4+ T cells. However, at 29 dpb with 1 μg mRNA-LNPs, males had lower frequencies of Kb-TSYKFESV-specific CD8+ T cells and were much less well protected than females from ECTV, also independently of CD4+ T cells. At 90 dpb with 1 μg EVM158 mRNA-LNPs, the frequencies of Kb-TSYKFESV-specific CD8+ T cells in males and females were similar, and both were similarly partially protected from ECTV, independently of CD4+ T cells. Therefore, at optimal or suboptimal doses of mRNA-LNP vaccines, CD4+ T cell help is unnecessary to induce protective anti-poxvirus CD8+ T cells specific to a dominant epitope. At suboptimal doses, protection of males requires more time to develop
Langerhans Cells Orchestrate the Protective Antiviral Innate Immune Response in the Lymph Node.
During disseminating viral infections, a swift innate immune response (IIR) in the draining lymph node (dLN) that restricts systemic viral spread is critical for optimal resistance to disease. However, it is unclear how this IIR is orchestrated. We show that after footpad infection of mice with ectromelia virus, dendritic cells (DCs) highly expressing major histocompatibility complex class II (MHC class IIhi DCs), including CD207+ epidermal Langerhans cells (LCs), CD103+CD207+ double-positive dermal DCs (DP-DCs), and CD103−CD207− double-negative dermal DCs (DN-DCs) migrate to the dLN from the skin carrying virus. MHC class IIhi DCs, predominantly LCs and DP-DCs, are the first cells upregulating IIR cytokines in the dLN. Preventing MHC class IIhi DC migration or depletion of LCs, but not DP-DC deficiency, suppresses the IIR in the dLN and results in high viral lethality. Therefore, LCs are the architects of an early IIR in the dLN that is critical for optimal resistance to a disseminating viral infection. Wong et al. show that by producing chemokines that recruit monocytes and by upregulating NKG2D ligands that activate ILCs, Langerhans cells are responsible for the innate immune cascade in the lymph node that is critical for survival of infection with a disseminating virus
Three-Dimensional Structure of Hybrid Magnetic Skyrmions Determined by Neutron Scattering
Magnetic skyrmions are topologically protected chiral spin textures which
present opportunities for next-generation magnetic data storage and logic
information technologies. The topology of these structures originates in the
geometric configuration of the magnetic spins - more generally described as the
structure. While the skyrmion structure is most often depicted using a 2D
projection of the three-dimensional structure, recent works have emphasized the
role of all three dimensions in determining the topology and their response to
external stimuli. In this work, grazing-incidence small-angle neutron
scattering and polarized neutron reflectometry are used to determine the
three-dimensional structure of hybrid skyrmions. The structure of the hybrid
skyrmions, which includes a combination of N\'eel-like and Bloch-like
components along their length, is expected to significantly contribute to their
notable stability, which includes ambient conditions. To interpret the neutron
scattering data, micromagnetic simulations of the hybrid skyrmions were
performed, and the corresponding diffraction patterns were determined using a
Born approximation transformation. The converged magnetic profile reveals the
magnetic structure along with the skyrmion depth profile, including the
thickness of the Bloch and N\'eel segments and the diameter of the core
Comprensión lectora inferencial en estudiantes universitarios
La comprensión lectora inferencial es un nivel de concepción más profundo y amplio de las ideas que exige una atribución de significados, relacionándolos con experiencias personales y conocimiento previo que posee el lector sobre el texto. El objetivo del presente estudio es identificar y comparar el nivel de comprensión lectora inferencial de estudiantes universitarios peruanos de recién ingreso. Para la recolección de datos se aplicó el test de Comprensión Lectora CLOZE que es una prueba estructurada (selección múltiple) de comprensión lectora de 06 textos y 60 preguntas inferenciales (léxicas, causales, macroestructurales, especificativas y de intención del autor) a 90 estudiantes, cuyas edades oscilan entre los 16 a 18 años, de recién ingreso (2021) de tres universidades privadas de la ciudad de Arequipa, Perú. Como resultado se observa que las mujeres presentan mayores niveles de comprensión lectora. A su vez, los estudiantes procedentes de escuelas privadas y de mayor edad logran comprender mejor los diferentes tipos de textos. Sin embargo, se ha observado dificultades significativas de comprensión lectora en los textos científicos, literarios y humanísticos. Se concluye que, en promedio, los sujetos que participaron en este estudio evidencian un bajo nivel de comprensión lectora al inicio de su periodo académico universitario
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