21,164 research outputs found
Increasing Awareness of the Risks Associated with Juuls in High School Students
The use of Juuls and other e-cigarettes has increased in Vermont high schools over the past year. Many students are not aware of the risks associated with the use of these products and believe that they cause no harm. This project focused on increasing communication between high school students and their healthcare providers to improve dialogue and learn the facts about using these projects.https://scholarworks.uvm.edu/fmclerk/1434/thumbnail.jp
Visualization of C. elegans transgenic arrays by GFP
BACKGROUND: Targeting the green fluorescent protein (GFP) via the E. coli lac repressor (LacI) to a specific DNA sequence, the lac operator (lacO), allows visualization of chromosomes in yeast and mammalian cells. In principle this method of visualization could be used for genetic mosaic analysis, which requires cell-autonomous markers that can be scored easily and at single cell resolution. The C. elegans lin-3 gene encodes an epidermal growth factor family (EGF) growth factor. lin-3 is expressed in the gonadal anchor cell and acts through LET-23 (transmembrane protein tyrosine kinase and ortholog of EGF receptor) to signal the vulval precursor cells to generate vulval tissue. lin-3 is expressed in the vulval cells later, and recent evidence raises the possibility that lin-3 acts in the vulval cells as a relay signal during vulval induction. It is thus of interest to test the site of action of lin-3 by mosaic analysis. RESULTS: We visualized transgenes in living C. elegans by targeting the green fluorescent protein (GFP) via the E. coli lac repressor (LacI) to a specific 256 sequence repeat of the lac operator (lacO) incorporated into transgenes. We engineered animals to express a nuclear-localized GFP-LacI fusion protein. C. elegans cells having a lacO transgene result in nuclear-localized bright spots (i.e., GFP-LacI bound to lacO). Cells with diffuse nuclear fluorescence correspond to unbound nuclear localized GFP-LacI. We detected chromosomes in living animals by chromosomally integrating the array of the lacO repeat sequence and visualizing the integrated transgene with GFP-LacI. This detection system can be applied to determine polyploidy as well as investigating chromosome segregation. To assess the GFP-LacI•lacO system as a marker for mosaic analysis, we conducted genetic mosaic analysis of the epidermal growth factor lin-3, expressed in the anchor cell. We establish that lin-3 acts in the anchor cell to induce vulva development, demonstrating this method's utility in detecting the presence of a transgene. CONCLUSION: The GFP-LacI•lacO transgene detection system works in C. elegans for visualization of chromosomes and extrachromosomal transgenes. It can be used as a marker for genetic mosaic analysis. The lacO repeat sequence as an extrachromosomal array becomes a valuable technique allowing rapid, accurate determination of spontaneous loss of the array, thereby allowing high-resolution mosaic analysis. The lin-3 gene is required in the anchor cell to induce the epidermal vulval precursors cells to undergo vulval development
Observation of Asymmetric Transport in Structures with Active Nonlinearities
A mechanism for asymmetric transport based on the interplay between the
fundamental symmetries of parity (P) and time (T) with nonlinearity is
presented. We experimentally demonstrate and theoretically analyze the
phenomenon using a pair of coupled van der Pol oscillators, as a reference
system, one with anharmonic gain and the other with complementary anharmonic
loss; connected to two transmission lines. An increase of the gain/loss
strength or the number of PT-symmetric nonlinear dimers in a chain, can
increase both the asymmetry and transmittance intensities.Comment: 5 pages, 5 figure
Coordinated Regulation of Intestinal Functions in C. elegans by LIN-35/Rb and SLR-2
LIN-35 is the sole C. elegans representative of the pocket protein family, which includes the mammalian Retinoblastoma protein pRb and its paralogs p107 and p130. In addition to having a well-established and central role in cell cycle regulation, pocket proteins have been increasingly implicated in the control of critical and diverse developmental and cellular processes. To gain a greater understanding of the roles of pocket proteins during development, we have characterized a synthetic genetic interaction between lin-35 and slr-2, which we show encodes a C2H2-type Zn-finger protein. Whereas animals harboring single mutations in lin-35 or slr-2 are viable and fertile, lin-35; slr-2 double mutants arrest uniformly in early larval development without obvious morphological defects. Using a combination of approaches including transcriptome profiling, mosaic analysis, starvation assays, and expression analysis, we demonstrate that both LIN-35 and SLR-2 act in the intestine to regulate the expression of many genes required for normal nutrient utilization. These findings represent a novel role for pRb family members in the maintenance of organ function. Our studies also shed light on the mechanistic basis of genetic redundancy among transcriptional regulators and suggest that synthetic interactions may result from the synergistic misregulation of one or more common targets
Role of IFN-α in Rheumatoid Arthritis
\ua9 2023, The Author(s).Purpose of Review: Type 1 interferons (IFN-I) are of increasing interest across a wide range of autoimmune rheumatic diseases. Historically, research into their role in rheumatoid arthritis (RA) has been relatively neglected, but recent work continues to highlight a potential contribution to RA pathophysiology. Recent Findings: We emphasise the importance of disease stage when examining IFN-I in RA and provide an overview on how IFN-I may have a direct role on a variety of relevant cellular functions. We explore how clinical trajectory may be influenced by increased IFN-I signalling, and also, the limitations of scores composed of interferon response genes. Relevant environmental triggers and inheritable RA genetic risk relating to IFN-I signalling are explored with emphasis on intriguing data potentially linking IFN-I exposure, epigenetic changes, and disease relevant processes. Summary: Whilst these data cumulatively illustrate a likely role for IFN-I in RA, they also highlight the knowledge gaps, particularly in populations at risk for RA, and suggest directions for future research to both better understand IFN-I biology and inform targeted therapeutic strategies
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Hydrocarbon ratios during PEM-WEST A: A model perspective
A useful application of the hydrocarbon measurements collected during the Pacific Exploratory Mission (PEM-West A) is as markers or indices of atmospheric processing. Traditionally, ratios of particular hydrocarbons have been interpreted as photochemical indices, since much of the effect due to atmospheric transport is assumed to cancel by using ratios. However, an ever increasing body of observatonial and theoretical evidence suggests that turbulent mixing associated with atmospheric transport influences certain hydrocarbon ratios significantly. In this study a three-dimensional mesoscale photochemical model is used to study the interaction of photochemistry and atmospheric mixing on select hydrocarbons. In terms of correlations and functional relationships between various alkanes the model results and PEM-West A hydrocarbon observations share many similar characteristics as well as explainable differences. When the three-dimensional model is applied to inert tracers, hydrocarbon ratios and other relationships exactly follow those expected by simple dilution with model-imposed "background air," and the three-dimensional results for reactive hydrocarbons are quite consistent with a combined influence of photochemistry and simple dilution. Analogous to these model results, relationships between various hydrocarbons collected during the PEM-West A experiment appear to be consistent with this simplified picture of photochemistry and dilution affecting individual air masses. When hydrocarbons are chosen that have negligeble contributions to clean background air, unambiguous determinations of the relative contributions to photochemistry and dilution can be estimated from the hydrocarbon samples. Both the three-dimensional model results and the observations imply an average characteristic lifetime for dilution with background air roughly equivalent to the photochemical lifetime of butane for the western Pacific lower troposphere. Moreover, the dominance of OH as the primary photochemical oxidant downwind of anthropogenic source regions can be inferred from correlations between the highly reactive alkane ratios. By incorporating back-trajectory information within the three-dimensional model analysis, a correspondence between time and a particular hydrocarbon or hydrocarbon ratio can be determined, and the influence of atmospheric mixing or photochemistry can be quantified. Results of the three-dimensional model study are compared and applied to the PEM-West A hydrocarbon dataset, yielding a practical methodology for determining average OH concentrations and atmospheric mixing rates from the hydrocarbon measurements. Aircraft data taken below 2 km during wall flights east of Japan imply a diurnal average OH concentration of ∼3 × 106 cm-3. The characteristic time for dilution with background air is estimated to be ∼2.5 days for the two study areas examined in this work. Copyright 1996 by the American Geophysical Union
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Rituximab in combination with high-dose methylprednisolone for the treatment of chronic lymphocytic leukemia.
We observed that high-dose methylprednisolone (HDMP) and rituximab was well tolerated and had promising activity when used in combination to treat patients with fludarabine-refractory chronic lymphocytic leukemia (CLL). This prompted us to evaluate the use of these agents in frontline therapy. A total of 28 patients with a median age of 65 years enrolled in this study. Patients received HDMP at 1 g/m(2) each day for 3 days during each of the three 4-week cycles together with rituximab and prophylactic antimicrobial therapy. The treatment was well tolerated with few adverse events of grade III or higher. The overall response rate was 96% (N=27). Nine patients (32%) achieved a complete remission (CR), two of which were without detectable minimal residual disease (MRD). Six patients with MRD received consolidation with alemtuzumab; five of these patients achieved an MRD-negative CR. With over 3 years of follow-up median progression-free survival was 30.3 months with only 39% of patients requiring additional therapy, and an overall survival was 96%. This study demonstrates that HDMP and rituximab is an effective nonmyelosuppressive treatment combination for patients with CLL that warrants consideration particularly for patients with limited myeloid reserve that might not tolerate standard treatment regimens
Insights into How HIAs are Characterized in the Press: Findings from a Media Analysis of Widely Circulated United States Newspapers
Background: Health impact assessments (HIAs) are burgeoning tools in the policy process, where the media plays a critical role by focusing attention on issues, informing consumers, and influencing positions. Examining how media portrays HIAs is critical to understanding HIAs in the policy context. Methods: This study considered how widely circulated, U.S. newspapers represent HIAs. After searching newspaper databases, we used a qualitative document analysis method consisting of open and axial coding to examine specific phrases of HIA depictions. Results: In coding over 1,000 unique phrases from the 62 documents generated in our search, we found an uptick in HIA-related publications since 2010. Coding these documents identified 46 distinct codes across 10 different themes. The two most prominent HIA-centered themes focused on HIA engagement and the HIA setting. While themes of policy and science, health determinants, and explanations of HIAs were also frequently featured, specific mentions of projected impacts, HIA processes, HIA values, and health outcomes were less prevalent. Conclusions: HIA media portrayals warrant further inquiry from researchers and practitioners. Focusing on how media portrays HIAs is consistent with several HIA steps. It is also important for a broader strategy to educate stakeholders about HIAs and to understand HIAs’ utility. HIA practitioners should develop and implement guidelines for media interaction and tracking that encourage practitioners to seek additional media attention and to focus such attention on health impacts and outcomes, HIA recommendations, and HIA values. Building on our work, researchers should examine HIA media portrayals beyond the context of this study
Delivery of human apolipoprotein (apo) E to liver by an [E1(-), E3(-), polymerase(-), pTP(-)] adenovirus vector containing a liver-specific promoter inhibits atherogenesis in immunocompetent apoE-deficient mice
Recombinant adenovirus (rAd)-mediated apoE gene transfer to the liver of apoE(-/-) mice is anti-atherogenic. However, first generation rAd vectors were associated with immune clearance of transduced hepatocytes, while an improved [E1(-), E3(-) polymerase(-)] adenovirus vector that persisted in the liver, had transient effects due to cellular shutdown of the cytomegalovirus (CMV) promoter (Ad-CMV-apoE). Here, we utilise an improved class of rAd vector with multiple deletions in the E1, E3, polymerase and pTP (pre-terminal protein) genes, which contains a modular synthetic liver-specific promoter (LSP) to drive expression of the human apoE cDNA (Ad-LSP-apoE) for hepatic gene transfer. Approximately 1 year old apoE(-/-) mice were injected intravenously with 4x10(10) virus particles of either Ad-LSP-apoE or Ad-CMV-apoE. Animals were monitored for plasma apoE, total plasma cholesterol and plasma lipoprotein distribution. The effect of Ad-LSP-apoE on atheroma progression was assessed in animals killed at 8 and 28 weeks after the injections. Ad-LSP-apoE vector administration gave sustained, though low, levels of plasma apoE throughout the study period without inducing a humoral immune response, but failed to reduce plasma cholesterol or normalize the adverse lipoprotein profile. Animals killed 8 weeks after the injections, demonstrated no significant retardation of atherosclerosis, whereas aortic lesions in those killed at 28 weeks were significantly reduced by 30% ( P< 0.006) compared to untreated animals. In summary, the combination of a multiply deleted rAd vector with a liver-specific promoter provided sustained low levels of plasma apoE, resulting in significant retardation of aortic atherosclerotic lesions
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