2,354 research outputs found
One Size Does Not Fit All: Meeting the Health Care Needs of Diverse Populations
Proposes a framework for meeting patients' cultural and linguistic needs: policies and procedures that support cultural competence, data collection, population-tailored services, and internal and external collaborations. Includes a self-assessment tool
Astrogliosis in a dish: Substrate stiffness induces astrogliosis in primary rat astrocytes
Astrogliosis due to brain injury or disease can lead to varying molecular and morphological changes in astrocytes. Magnetic resonance elastography and ultrasound have demonstrated that brain stiffness varies with age and disease state. However, there is a lack in understanding the role of varied stiffness on the progression of astrogliosis highlighting a critical need to engineer in vitro models that mimic disease stages. Such models need to incorporate the dynamic changes in the brain microenvironment including the stiffness changes. In this study we developed a polydimethyl siloxane (PDMS) based platform that modeled the physiologically relevant stiffness of brain in both a healthy (200 Pa) and diseased (8000 Pa) state to investigate the effect of stiffness on astrocyte function. We observed that astrocytes grown on soft substrates displayed a consistently more quiescent phenotype while those on stiff substrates displayed an astrogliosis-like morphology. In addition to morphological changes, astrocytes cultured on stiff substrates demonstrated significant increase in other astrogliosis hallmarks – cellular proliferation and glial fibrillary acidic protein (GFAP) protein expression. Furthermore, culturing astrocytes on a stiff surface resulted in increased reactive oxygen species (ROS) production, increased super oxide dismutase activity and decreased glutamate uptake. Our platform lends itself for study of potential therapeutic strategies for brain injury focusing on the intricate brain microenvironment-astrocytes signaling pathways
Astrogliosis in a dish: Substrate stiffness induces astrogliosis in primary rat astrocytes
Astrogliosis due to brain injury or disease can lead to varying molecular and morphological changes in astrocytes. Magnetic resonance elastography and ultrasound have demonstrated that brain stiffness varies with age and disease state. However, there is a lack in understanding the role of varied stiffness on the progression of astrogliosis highlighting a critical need to engineer in vitro models that mimic disease stages. Such models need to incorporate the dynamic changes in the brain microenvironment including the stiffness changes. In this study we developed a polydimethyl siloxane (PDMS) based platform that modeled the physiologically relevant stiffness of brain in both a healthy (200 Pa) and diseased (8000 Pa) state to investigate the effect of stiffness on astrocyte function. We observed that astrocytes grown on soft substrates displayed a consistently more quiescent phenotype while those on stiff substrates displayed an astrogliosis-like morphology. In addition to morphological changes, astrocytes cultured on stiff substrates demonstrated significant increase in other astrogliosis hallmarks – cellular proliferation and glial fibrillary acidic protein (GFAP) protein expression. Furthermore, culturing astrocytes on a stiff surface resulted in increased reactive oxygen species (ROS) production, increased super oxide dismutase activity and decreased glutamate uptake. Our platform lends itself for study of potential therapeutic strategies for brain injury focusing on the intricate brain microenvironment-astrocytes signaling pathways
Hyaluronic acid-conjugated liposome nanoparticles for targeted delivery to CD44 overexpressing glioblastoma cells
Glioblastoma Multiforme (GBM) is a highly prevalent and deadly brain malignancy characterized by poor prognosis and restricted disease management potential. Despite the success of nanocarrier systems to improve drug/gene therapy for cancer, active targeting specificity remains a major hurdle for GBM. Additionally, since the brain is a multi-cell type organ, there is a critical need to develop an approach to distinguish between GBM cells and healthy brain cells for safe and successful treatment. In this report, we have incorporated hyaluronic acid (HA) as an active targeting ligand for GBM. To do so, we employed HA conjugated liposomes (HALNPs) to study the uptake pathway in key cells in the brain including primary astrocytes, microglia, and human GBM cells. We observed that the HALNPs specifically target GBM cells over other brain cells due to higher expression of CD44 in tumor cells. Furthermore, CD44 driven HALNP uptake into GBM cells resulted in lysosomal evasion and increased efficacy of Doxorubicin, a model anti-neoplastic agent, while the astrocytes and microglia cells exhibited extensive HALNP-lysosome co-localization and decreased antineoplastic potency. In summary, novel CD44 targeted lipid based nanocarriers appear to be proficient in mediating site-specific delivery of drugs via CD44 receptors in GBM cells, with an improved therapeutic margin and safety
Use of automated response systems in the small sized class
An interactive demonstration of various teaching methods using Remote Response Systems (Automated Response Systems, Personal Response Systems, Clickers ) as they were applied to the small sized class (\u3c 20 students). Most of the research with clickers has been in large classes. The methods used (peer instruction, group discussion, and simple polling with contingency teaching) will be demonstrated and results of the initial study with a class of 14 students will be presented. Internet access for all participants (local computers, laptops, or phones) will be necessary for this activity
Mitochondrial dysfunction and loss of glutamate uptake in primary astrocytes exposed to titanium dioxide nanoparticles
Titanium dioxide (TiO2) nanoparticles are currently the second most produced engineered nanomaterial in the world with vast usage in consumer products leading to recurrent human exposure. Animal studies indicate significant nanoparticle accumulation in the brain while cellular toxicity studies demonstrate negative effects on neuronal cell viability and function. However, the toxicological effects of nanoparticles on astrocytes, the most abundant cells in the brain, have not been extensively investigated. Therefore, we determined the sub-toxic effect of three different TiO2 nanoparticles (rutile, anatase and commercially available P25 TiO2 nanoparticles) on primary rat cortical astrocytes. We evaluated some events related to astrocyte functions and mitochondrial dysregulation: (1) glutamate uptake; (2) redox signaling mechanisms
by measuring ROS production; (3) the expression patterns of dynamin-related proteins (DRPs) and mitofusins 1 and 2, whose expression is central to mitochondrial dynamics; and (4) mitochondrial morphology by MitoTracker® Red CMXRos staining. Anatase, rutile and P25 were found to have LC50 values of 88.22 ± 10.56 ppm, 136.0 ± 31.73 ppm and 62.37 ± 9.06 ppm respectively indicating nanoparticle specific toxicity. All three TiO2 nanoparticles induced a significant loss in glutamate uptake indicative of a
loss in vital astrocyte function. TiO2 nanoparticles also induced an increase in reactive oxygen species generation, and a decrease in mitochondrial membrane potential, suggesting mitochondrial damage. TiO2 nanoparticle exposure altered expression patterns of DRPs at low concentrations (25 ppm) and apoptotic fission at high concentrations (100 ppm). TiO2 nanoparticle exposure also resulted in changes to mitochondrial morphology confirmed by mitochondrial staining. Collectively, our data provide compelling evidence that TiO2 nanoparticle exposure has potential implications in astrocyte-mediated neurological dysfunction
The CHI'24 Workshop on the Future of Cognitive Personal Informatics
While Human-Computer Interaction (HCI) has contributed to demonstrating that physiological measures can be used to detect cognitive changes, engineering and machine learning will bring these to application in consumer wearable technology. For HCI, many open questions remain, such as: What happens when this becomes a cognitive form of personal informatics? What goals do we have for our daily cognitive activity? How should such a complex concept be conveyed to users to be useful in their everyday lives? How can we mitigate potential ethical concerns? This is different to designing BCI interactions; we are concerned with understanding how people will live with consumer neurotechnology. This workshop will directly address the future of Cognitive Personal Informatics (CPI), by bringing together design, BCI and physiological data, ethics, and personal informatics researchers to discuss and set the research agenda in this inevitable future
Genotypic and Phenotypic Characterization of Aerosolized Bacteria Collected From African Dust Events
Twenty-one bacteria were isolated and characterized from air samples collected in Africa and the Caribbean by the United States Geological Survey (USGS). Isolates were selected based on preliminary characterization as possible pathogens. Identification of the bacterial isolates was achieved using 16S rRNA gene sequence analysis, fatty acid methyl esters (FAMEs) profiling, the BIOLOG Microlog® System (carbon substrate assay), and repetitive extragenic palindromic (REP)-PCR analysis. The majority of isolates (18/21) were identified as species of the genus Bacillus. Three isolates were classified within the Bacillus cereus senso lato group, which includes Bacillus anthracis, Bacillus thuringiensis, and Bacillus cereus strains. One isolate was identified as a Staphylococcus sp., most closely related to species (i.e., Staphylococcus kloosii, Staphylococcus warneri) that are commonly associated with human or animal skin, but can also act as opportunistic pathogen. Another isolate was tentatively identified as Tsukamurella inchonensis, a known respiratory pathogen, and was resistant to the ten antibiotics tested including vancomycin
Learning from Engineers to Develop a Model of Disciplinary Literacy in Engineering (Year 3)
Purpose This paper will the describe the overall project goals, activities, preliminary findings, and future work on this project. The purpose of this project is to develop a model of Disciplinary Literacy Instruction (DLI) in engineering that can be used in both K-12 and undergraduate engineering settings. This model of DLI will be informed by knowledge about the ways practicing engineers across four disciplines of engineering (i.e., electrical/computer, mechanical/aerospace, civil/environmental, and chemical/biological) read, interpret, evaluate, and generate texts in the context of their work environment. This information will be translated into a model of DLI in engineering to teach students how to use authentic engineering literacy practices as they learn discipline specific engineering content.
Project Activities During the first year of this project, we conducted on-site observations with two electrical engineers and two mechanical engineers. In addition, we held interviews and conducted think-aloud protocols that were informed by the observations with each engineer. From these data sources, we developed a codebook describing the types of texts that the engineers interpreted, evaluated, and generated at the workplace. worked with both mechanical and electrical engineering consultants to help refine and revise the codes and code definitions to enhance their authenticity to each discipline. To further ensure the quality of our data analysis procedures, we sought feedback on our codes from three advisory board consultants having expertise in disciplinary literacy, engineering, and K-12 engineering education.
During the second year of this project, we analyzed the interview and think-aloud protocol transcripts from the electrical and mechanical engineers to generate themes that described the interpretive and evaluative frameworks the engineers used as they solved a technical problem or generated a solution for a client or customer. Similarly, we developed themes that described the socially situated activities in which the previously defined genres were embedded. Taken together, these frameworks and activities inform the development of the DLI model in engineering. We also began collecting observation, interview, and think aloud data with one civil and one environmental engineer during this year.
Currently, in the third year of this project, we are analyzing the observation field notes and the interview and think-aloud protocol transcripts from the civil and environmental engineers. Simultaneously, we are generating data with the final pair of engineers: one biological and one chemical engineer. We continue to refine our codebook by adding new genres as they appear and merging any similar, existing genres to capture the range of texts with which the engineers engaged. Engineering consultants from both the civil and environmental disciplines will provide feedback on our codes. Combined data from this phase with previous phases will be used develop disciplinary specific curricular materials for K-12 and undergraduate engineering education.
Future Activities The data collected and analyzed throughout the project will inform the development of a model for DLI in engineering that can be used by teachers in both undergraduate and K-12 educational settings. This model will provide a framework for teachers to instruct students on how to use the authentic reading and writing strategies that practicing engineers use while solving problems. By providing a diverse set of students with exposure to these literacy practices in school at a young age, a model of DLI in engineering has the potential to remove literacy-based barriers that may deter students from pursuing engineering pathways
The long-term relationship between cannabis and heroin use:An 18-20-year follow-up of the Australian Treatment Outcome Study (ATOS)
Objective: Cannabis use is common among those with opioid use disorders (OUD), but it remains unclear whether cannabis use is associated with an increase or reduction in illicit opioid use. To extend upon previous longitudinal studies with limited follow-ups, the current study examined a within-person reciprocal relationship between cannabis and heroin use at several follow-ups over 18-20-years. Methods: The Australian Treatment Outcome Study (ATOS) recruited 615 people with heroin dependence in 2001-2002 and reinterviewed at 3-, 12-, 24-, 36-months, 11 and 18-20-years post-baseline. Heroin and cannabis use were assessed at each time point using the Opiate Treatment Index (OTI). A random intercept cross-lagged panel model (RI-CLPM) was conducted to identify within-person relationships between cannabis use and heroin use at subsequent follow-ups. Results: After accounting for a range of demographic, other substance use, mental and physical health measures, an increase in cannabis use at 24-months was associated with an increase in heroin use at 36months (Estimate = 0.21, SE = 0.10, p = 0.03). Additionally, an increase in heroin use at 3-months and 24-months post-baseline was associated with a decrease in cannabis use at 12-months (Estimate = -0.27, SE = 0.09, p <0.01) and 36-months post-baseline (Estimate = -0.22, SE = 0.08, p <0.01). All other cross-lagged associations were not significant. Conclusions: Although there was some evidence of a significant relationship between cannabis and heroin use at earlier follow-ups, this was sparse, and inconsistent across time-points. Overall, there was insufficient evidence to suggest a unidirectional or bidirectional relationship between the use of these substances
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