290 research outputs found

    The Impact of an Advisor-Advisee Mentoring Program on the Achievement, School Engagement, and Behavior Outcomes of Rural Eighth Grade Students

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    The purpose of this exploratory two-group pretest-posttest comparative survey study was to determine the effect of a team adviser-advisee academic, behavior, and character mentoring program on the achievement, school engagement, and behavior outcomes of eighth grade students determined to be above ( n = 21) and below (n = 15) eligibility guidelines for free and reduced price lunch participation during the 2008-2009 school year

    Skin involvement in early diffuse cutaneous systemic sclerosis: an unmet clinical need

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    Diffuse cutaneous systemic sclerosis (dcSSc) is associated with high mortality resulting from early internal-organ involvement. Clinicians therefore tend to focus on early diagnosis and treatment of potentially life-threatening cardiorespiratory and renal disease. However, the rapidly progressive painful, itchy skin tightening that characterizes dcSSc is the symptom that has the greatest effect on patients' quality of life, and there is currently no effective disease-modifying treatment for it. Considerable advances have been made in predicting the extent and rate of skin-disease progression (which vary between patients), including the development of techniques such as molecular analysis of skin biopsy samples. Risk stratification for progressive skin disease is especially relevant now that haematopoietic stem-cell transplantation is a treatment option, because stratification will inform the balance of risk versus benefit for each patient. Measurement of skin disease is a major challenge. Results from clinical trials have highlighted limitations of the modified Rodnan skin score (the current gold standard). Alternative patient-reported and other potential outcome measures have been and are being developed. Patients with early dcSSc should be referred to specialist centres to ensure best-practice management, including the management of their skin disease, and to maximize opportunities for inclusion in clinical trials

    Part I: Super-resolution Microscopy Method Development Part II: Investigations of Transcription Regulation by Chromosomal Organization in Bacteria

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    Part I: SMLM provides not only high-resolution images of molecular assemblies beyond the diffraction limit but also enables quantitative analysis of the dynamics and compositions. However, challenges in imaging and analysis due to cell geometry, resolution limit, and fluorophore properties impede the full potential of SMLM. To address these challenges, I first developed a single- molecule tracking methodology that minimizes the confinement of diffusing molecules to obtain accurate diffusion coefficients and transition rates. Next, I developed a methodology to improve three-dimensional (3D)-SMLM imaging by directly taking into account the variability of 3D point-spread-functions, which produces superior resolution compared to existing methodologies. Finally, I developed a method to correct for blinking-artifacts. Blinking-artifacts are caused by repeated localizations of the same fluorophores, which distort images and produce false nanoclusters. I derived a method to find the ā€ground- truthā€ of the underlying pairwise distribution without any additional calibration. This ground truth enables me to identify the true underlying spatial distribution of molecules in the SMLM image, solving a problem that has long persisted in the field. Part II: It is well established that chromosomal organization dramatically influences transcription, but the underlying mechanisms remain elusive. We hypothesize that supercoiling constrained by the chromosomal topology has an effect on transcription rate and hence coordinates expression within the same topological domain. To examine this hypothesis, I developed a theoretical model to account directly for the buildup of supercoiling due to transcription in a DNA-loop. To investigate how the topology of the chromosome influences transcription further, I then developed the first in vivo assays to manipulate the formation of a ā€œlargeā€ chromosomal DNA topological domain in E. coli cells to examine transcription activity of multiple genes enclosed in the domain. My experiments showed that domain formation decreases expression levels of genes both inside and outside the domain ā€” demonstrating a ā€long-rangeā€ cis-regulatory mechanism due to the ā€œarchitectureā€ of the chromosome within bacteria. Finally, using quantitative SMLM, we investigated how ā€large-scaleā€ chromosome organization affects the spatial organization of RNA-polymerase (RNAP). We discovered RNAP clusters engaged in active ribosomal RNA synthesis; whose organization is ā€œdrivenā€ by the chromosomal organization

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    A century-long record of plant evolution reconstructed from a coastal marsh seed bank

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    Evidence is mounting that climate-driven shifts in environmental conditions can elicit organismal evolution, yet there are sparingly few long-term records that document the tempo and progression of responses, particularly for plants capable of transforming ecosystems. In this study, we ā€œresurrectedā€ cohorts of a foundational coastal marsh sedge (Schoenoplectus americanus) from a time-stratified seed bank to reconstruct a century-long record of heritable variation in response to salinity exposure. Common-garden experiments revealed that S. americanus exhibits heritable variation in phenotypic traits and biomass-based measures of salinity tolerance. We found that responses to salinity exposure differed among the revived cohorts, with plants from the early 20th century exhibiting greater salinity tolerance than those from the mid to late 20th century. Fluctuations in salinity tolerance could reflect stochastic variation but a congruent record of genotypic variation points to the alternative possibility that the loss and gain in functionality are driven by selection, with comparisons to historical rainfall and paleosalinity records suggesting that selective pressures vary according to shifting estuarine conditions. Because salinity tolerance in S. americanus is tightly coupled to primary productivity and other vital ecosystem attributes, these findings indicate that organismal evolution merits further consideration as a factor shaping coastal marsh responses to climate change

    Smooth Muscle Stiffness Sensitivity is Driven by Soluble and Insoluble ECM Chemistry

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    Smooth muscle cell (SMC) invasion into plaques and subsequent proliferation is a major factor in the progression of atherosclerosis. During disease progression, SMCs experience major changes in their microenvironment, such as what integrin-binding sites are exposed, the portfolio of soluble factors available, and the elasticity and modulus of the surrounding vessel wall. We have developed a hydrogel biomaterial platform to examine the combined effect of these changes on SMC phenotype. We were particularly interested in how the chemical microenvironment affected the ability of SMCs to sense and respond to modulus. To our surprise, we observed that integrin binding and soluble factors are major drivers of several critical SMC behaviors, such as motility, proliferation, invasion, and differentiation marker expres- sion, and these factors modulated the effect of stiffness on proliferation and migration. Overall, modulus only modestly affected behaviors other than proliferation, relative to integrin binding and soluble factors. Surprisingly, patho- logical behaviors (proliferation, motility) are not inversely related to SMC marker expression, in direct conļ¬‚ict with previous studies on substrates coupled with single extracel- lular matrix (ECM) proteins. A high-throughput bead-based ELISA approach and inhibitor studies revealed that differ- entiation marker expression is mediated chieļ¬‚y via focal adhesion kinase (FAK) signaling, and we propose that integrin binding and FAK drive the transition from a migratory to a proliferative phenotype. We emphasize the importance of increasing the complexity of in vitro testing platforms to capture these subtleties in cell phenotypes and signaling, in order to better recapitulate important features of in vivo disease and elucidate potential context-dependent therapeutic targets

    Effectiveness and safety of different estradiol regimens in transgender women (TREAT study): Protocol for a randomized controlled trial

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    BACKGROUND: Current guidelines for gender-affirming hormone therapy (GAHT) for transgender women are mostly based on clinical experience from experts in the field and treatments used on postmenopausal women. While care is currently provided with the best available evidence, there is a critical gap in knowledge about the safest and most effective estradiol routes of administration for GAHT in transgender women; this statement is supported by the World Professional Association for Transgender Health on their Standards of Care for the Health of Transgender and Gender Diverse People, version 8. Furthermore, the reported rates of cardiometabolic adverse events in transgender women highlight the importance of investigating changes in lipoproteins, glucose, and insulin sensitivity, among other markers while receiving GAHT. OBJECTIVE: This study aims to evaluate the degree of testosterone suppression achieved at 1, 6, and 12 months in treatment-naive transgender women when randomized to GAHT with estradiol and spironolactone as antiandrogens. As a secondary aim, this study will assess the treatment effect on metabolic and coagulation factors from baseline to 6 and 12 months after initiating GAHT. METHODS: This is a prospective pilot, open-label, randomized clinical trial conducted at an adult transgender clinic in a tertiary medical center. The 3 treatment arms include once-daily sublingual 17-Ī² estradiol, twice-daily sublingual 17-Ī² estradiol, and transdermal 17-Ī² estradiol. All participants received spironolactone as an antiandrogen. Transgender women aged 18 to 45 years who are being evaluated for the initiation of GAHT with 17-Ī² estradiol and did not have a history of coagulopathy, cigarette smoking, liver disease, dyslipidemia requiring treatment, or use of gonadotropin-releasing hormone agonist were eligible to enroll. The main outcome is the total testosterone suppression at 1 and 6 months after the initiation of GAHT, and the secondary outcome is to assess treatment effect in a lipid panel; homeostatic model assessment for insulin resistance; coagulation factors II, IX, and XI; Von Willebrand factor; activated protein C resistance; protein C; and protein S at baseline, 6 months, and 12 months after therapy is initiated. RESULTS: This study was funded in March 2022, and enrollment concluded in August 2022. It was concluded in July 2023, and currently, the results are being analyzed for publication. CONCLUSIONS: The Transgender Estradiol Affirming Therapy (TREAT) study offers a rigorous and reproducible approach to answer important questions regarding GAHT in transgender women, specifically, the most effective 17-Ī² estradiol regimen to suppress testosterone levels to 50 ng/dL, as currently recommended. TRIAL REGISTRATION: ClinicalTrials.gov NCT05010707; https://clinicaltrials.gov/study/NCT05010707. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/53092

    Clinical trial protocol: PRednisolone in early diffuse cutaneous Systemic Sclerosis (PRedSS)

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    From SAGE Publishing via Jisc Publications RouterHistory: received 2020-05-08, accepted 2020-08-16, epub 2020-09-17Publication status: PublishedFunder: Versus Arthritis; FundRef: https://doi.org/10.13039/501100012041; Grant(s): 21021Background:: Many of the painful, disabling features of early diffuse cutaneous systemic sclerosis have an inflammatory component and are potentially treatable with corticosteroid therapy. These features include painful and itchy skin, fatigue and musculoskeletal involvement. Yet many clinicians are understandably reluctant to prescribe corticosteroids because of the concern that these are a risk factor for scleroderma renal crisis. The aim of PRedSS (PRednisolone in early diffuse cutaneous Systemic Sclerosis) is to evaluate the efficacy and safety of moderate dose prednisolone in patients with early diffuse cutaneous systemic sclerosis, specifically whether moderate dose prednisolone is (a) effective in terms of reducing pain and disability, and improving skin score and (b) safe, with particular reference to renal function. Methods:: PRedSS is a Phase II, multicentre, double-blind randomised controlled trial which aims to recruit 72 patients with early diffuse cutaneous systemic sclerosis. Patients are randomised to receive either prednisolone (dosage approximately 0.3 mg/kg) or placebo therapy for 6 months. The two co-primary outcome measures are the difference in mean Health Assessment Questionnaire Disability Index at 3 months and the difference in modified Rodnan skin score at 3 months. Secondary outcome measures include patient reported outcome measures of itch, hand function, anxiety and depression, and helplessness. Results:: Recruitment commenced in December 2017 and after a slow start (due to delays in opening centres) 25 patients have now been recruited. Conclusion:: PRedSS should help to answer the question as to whether clinicians should or should not prescribe prednisolone in early diffuse cutaneous systemic sclerosis
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