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An Investigation Of Pyclen Metal Chelator Release On The Aggregation Of Amyloid-Beta
No full textAlzheimer's Disease (AD) affects over 6.5 million Americans over the age of 65. Previous research links AD with Amyloid-Beta-40 (A) aggregation in the brain, which creates neurotoxic plaques, associated with AD. A potential mechanism in the treatment of AD is using therapeutics that will prevent the formation of these plaques, which is possible with Metal ion chelation therapy.
Metal ion chelation therapy ideally stops metal ions from aiding in the aggregation of A. However, to deliver metal chelating agents to the brain, a drug-delivery mechanism is required that will be able to deliver this potential therapeutic across the Blood-Brain Barrier. Mesoporous silica is a potential drug delivery material due to its small particle size, high loading capacity, surface tunability, and biocompatibility. Along with these characteristics, mesoporous silica can create a sustained release profile of a given therapeutic, allowing for a slow and steady release profile, reducing the risks of medication side effects.
This project seeks to establish the optimal loading capacities of a class of potential metal ion chelate therapeutic molecules known as pyclens into mesoporous silica, each with different pyridyl moieties and chemical functionalities along the rim of the molecule. Loading capacity measurements for these pyclen derivatives reveal loading percentages in the 10-25% range, varying by pyclen identity. Additionally, release studies monitored diffusion over time to find which pyclen molecule achieved "sustained" ll loaded pyclen species were able to show sustained release after 20 minutes, both in the presence and absence of copper metal ions (Cu2+). Turbidity assays with A present showed that all pyclen species decreased protein aggregation in the presence of Cu2+ metal ions, relative to non-pyclen controls, showing that all pyclen species were able to successfully prevent the aggregation of A in the presence of Cu2+ metal ions
Impact of a short-term antibiotic cycle on glucose control in adults with overweight or obesity
No full textEpidemiologic evidence suggests that antibiotic frequency increases insulin resistance and reduces glucose control. However, interventional human studies have produced conflicting results on the effects of short-term antibiotic cycles on glucose control, demonstrating either no effect or harmful effects on glucose control. Our study aimed to contribute to the current body of literature examining the effects of short-term antibiotic cycles on glucose control in order to better clarify and understand the accumulated exposure risk of chronic insulin resistance and glucose dysregulation. Despite a small sample size (n=11), a short antibiotic cycle (3 days of therapeutic dosge of Vancomycin) significantly increased serum fasting insulin (p=0.037) and fasting glucose (0.023) levels from baseline. Our study indicates that short antibiotic cycles can induce acute harmful effects and warrants for further research examining the chronic and accumulated risk of antibiotic exposures. Furthermore, this study highlights the need for research on methods to prevent acute antibiotic-induced glucose control disruption
Mitigating the curse of complexity: The role of focus and the implications for costs of care
No full textThere has been a resurgence of interest in the role of operational focus in the healthcare operations literature in the backdrop of increasing demand for efficient and effective care. However, the evidence on the benefits of focus in healthcare is mixed. Our study proposes that a key piece of this puzzle that is been largely missing is an explicit consideration of the complexity of patient care needs. Specifically, our study serves to answer the questions: How does the complexity of care requirements affect care delivery operations? How does focus across the hierarchical levels of care affect care delivery outcomes across complexity regimes? The empirical analysis in the study is based on a large generalizable dataset of 246,663 patient discharges across 26 categories at 154 hospitals. We develop a multi†factor measure of complexity of care requirements. The study results point to the deleterious impact of complexity on the costs of care. Next, our findings highlight the differential impact of focus across hierarchical levels (task†level focus, category†level focus, and selective focus in related areas) on the costs of care. Third, our study findings highlight the role of focus in mitigating the effects of complexity on costs in a healthcare setting. We discuss the implications of the study findings for theory and practice, and the directions for future research
Painful facial, oral, and genital ulcers
No full textA 32-year-old otherwise healthy male presented to the dermatology clinic in Rio de Janeiro, Brazil, with a 2-day history of multiple painful, non-pruritic ulcers in the genital and facial regions, fever, odynophagia, headache, and fatigue. Physical examination revealed pustules and vesicles with central umbilication at the same stage of development and targetoid crusted ulcers on the right inguinal area (Fig 1), base of the penis, right gluteal region, and left cheek along with bilateral painful inguinal adenopathy. The oropharynx showed erythematous patches and erosions with white exudate
Utility of routine type and cross for anterior cervical discectomy and fusion: A retrospective review
No full textBackground: Preoperative type and screen and type and cross are routinely obtained in patients undergoing elective cervical spine surgeries. This is despite low perioperative transfusion rates, particularly in patients undergoing anterior cervical discectomy and fusion (ACDF). Methods: We conducted a retrospective cohort study at a single tertiary medical center of all patients 18 years of age or older undergoing elective ACDF for degenerative cervical spine disease between January 2016 and January 2021. Our primary outcome measures included the frequency of type and screen/crossmatch orders, rate of perioperative transfusion, and crossmatch to transfusion (C/T) ratio. Secondary outcomes included differences between preoperative and postoperative hemoglobin and hematocrit.Results: In total, 1,162 patients were identified. There were no cases of intraoperative transfusion. The overall transfusion rate was less than 1%, with only 1 patient receiving a blood product transfusion during their hospital admission. This patient received 2 units of platelets for severe preoperative thrombocytopenia. Yet, 961 patients (83%) received ABO/Rh blood typing and screening and 647 patients (56%) had their blood typed and crossed. A total of 1,318 units of blood were crossmatched, with no units of packed red blood cells (pRBCs) transfused and only 2 units of platelets transfused, achieving a high crossmatch to transfusion (C/T) ratio of 659:1.Conclusions: Among 1,162 patients who underwent elective ACDF at our institution, there were no patients who required an intraoperative or emergent blood transfusion. Furthermore, routine type and screen and crossmatch in patients undergoing elective ACDF at our insitution is associated with a high C/T ratio, suggestive of inefficient usage of blood products
REPUBLICAN WOMEN AND THE IMPACT OF THE POST-DOBBS ELECTORAL ENVIRONMENT ON CANDIDATE SUCCESS
No full textThe political environment in America experienced a phenomenal change in the summer of 2022 when the Supreme Court decided to overturn the federally-protected right to abortion, instead turning it to the states to legislate. This study answers the following questions: Are the political contextual factors that typically affect Republican women still relevant today, given the current abortion climate post-Dobbs? Republican women have been consistently underrepresented in elected office, but recently more conservative women are being elected and taking on women?s issues which are increasingly relevant among many voters. By relying on an extensive examination of the academic literature of factors that normally affect Republican women, my study was conducted to test the hypothesis that the impact of the district, political, and contextual variables in the post-Dobbs electoral environment uniquely impacts the electoral success of Republican women. The Dobbs decision came about in the midst of the midterm elections in full swing for Congress, offering a unique opportunity to observe how Republican women approached one of the more divisive and polarizing issues today. In reality, the electoral environments for the 82 female Republican candidates for the House of Representatives revealed that while incumbency, campaign expenditures, and partisanship of districts were all significant, there were political contextual factors that differed across districts and uniquely impacted electoral success. Based on the inferential statistics, I infer these changes in the electoral environments are due to the contemporary abortion climate that exists from the Dobbs decision. There are limitations to this study due to the timely nature of the Dobbs decision and the time of this study being conducted. However, this study demonstrates the importance of examining the ways in which important social and political issues can manifest uniquely for Republican women, and if the implications may impact the slow but continual electoral success of this underrepresented population
Understanding Omnichannel Shopping Behaviors: Incorporating Channel Integration into The Theory of Reasoned Action: Understanding Omnichannel Shopping Behaviors: Incorporating Channel Integration into The Theory of Reasoned Action
No full textYoung consumers prefer to switch shopping channels freely for optimal shopping results and experiences. To meet these changing needs, retailers have begun implementing an omnichannel retail strategy that integrates their various shopping channels to create a consistent and seamless shopping environment. Thus, this study examines the effect of young consumers' perceptions of the retailer's channel consistency and seamlessness on their attitudes, intentions, and behaviors in the omnichannel retailing context. We incorporated the concept of channel consistency and seamlessness into the Theory of Reasoned Action to address the study objective. A consumer research firm was hired to recruit millennials and Gen Z consumers, and online surveys took place in the U.S. in 2019, and 430 usable surveys were analyzed with SPSS and AMOS. The results confirmed that consumers¿ perception of channel seamlessness positively impacted their attitudes toward omnichannel shopping. Furthermore, these attitudes and subjective norms increased their intentions, leading to engagement in omnichannel shopping. The findings suggest that retailers must create smooth and uninterrupted shopping experiences across channels and proactively manage social components to create a customer¿s omnichannel shopping experienc
Environmental and anthropogenic variables influence the distribution of a habitat specialist (Sylvilagus aquaticus) in a large urban forest
No full textConservation of habitat fragments, including those embedded in an urban matrix which typically support fewer species than those in other landscape contexts, is important for combatting the global extinction crisis. Because urban avoiding species are often absent from habitat fragments within an urban matrix, studies of their distributions in these habitats are rare, and therefore the mechanisms by which species are excluded from habitat fragments within an urban matrix are poorly understood. We investigated the impacts of urbanization in the matrix (e.g., noise pollution, light pollution, invasive species) on the distribution of an urban avoiding species, the swamp rabbit (Sylvilagus aquaticus) in the largest urban forest fragment in the United States. We used the location of swamp rabbit latrines and presence-background species distribution modeling to reveal the impacts of urbanization in the matrix on swamp rabbit distribution while accounting for spatial heterogeneity in naturally occurring environmental variables. Swamp rabbits used mature forest, heterogeneously structured forest, and moderately inundated forest, and they avoided areas of high (Sus scrofa) hog activity at our study site. Our findings provide novel information to conservation practitioners and urban planners attempting to conserve high priority species in habitat fragments as urbanization continues to spread. ¿ 2023 The Authors. Conservation Science and Practice published by Wiley Periodicals LLC on behalf of Society for Conservation Biology
Actions are authentic, but are leaders? A reconceptualization of authenticity and leadership practice
No full textSince the Gallup Leadership Summit, authentic leadership has ascended as a central topic of inquiry owing to practitioners and academicians' desire for more positive types of leadership (Braun and Peus, 2018; Ilies et al., 2005; Luthans and Avolio, 2003; Weiss et al., 2018). Like much of the extant literature, our article centers on authentic leadership as defined and operationalized by Walumbwa et al.'s (2008) four-part framework, which views authentic leaders as individuals who possess high levels of (a) self-awareness, (b) balanced processing, (c) relational transparency, and (d) having an internalized moral perspective. This definition originated from positive psychology and gained popularity, in part, because it offers a morally grounded response for organizations seeking to rebuild confidence, hope, and optimism amid growing corporate and societal problems (e.g., Avolio and Gardner, 2005; Avolio et al., 2004). As a result, scholarly research on authentic leadership has surged (see Gardner et al., 2011, for a review), quickly gaining traction with a wide array of stakeholders who desire leaders that promote behavioral integrity (Leroy et al., 2012), encourage creativity (Semedo et al., 2017), and foster intra-team trust as well as helping behaviors (Hirst et al., 2016)
Monoclonal Antibodies in Hospitalised Patients with COVID-19: The Role of SARS-COV-2 Serostatus in an Evolving Pandemic
No full textAppropriately selected neutralising monoclonal antibodies (nmAbs) are an effective treatment for patients with mild or moderate coronavirus disease 2019 (COVID-19) who are at high risk of progression to severe disease. In contrast, the efficacy of nmAbs in patients hospitalised with COVID-19 has been mixed, and clinical benefit has largely been restricted to seronegative patients [i.e. those lacking endogenous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies] in the trials with positive outcomes. This review summarises the major clinical trial data investigating nmAb treatment for hospitalised patients with COVID-19, and explores current definitions of seropositivity, what they mean in a late-pandemic context and discusses the current late-pandemic challenges associated with defining ¿seroprotection' in a clinically meaningful way. We conclude that following widespread vaccination, increasing numbers of prior infections and emerging viral variants, seropositivity now reflects a range of immune coverage rather than a binary tool with which to aid decision-making on a clinically actionable timescale. Treatment decisions with nmAbs in a late-pandemic context would therefore likely best rely on information regarding clinical status, time since symptom onset, underlying patient condition(s) and the dominant circulating variant, should they be approved for future use in hospitalised patients with COVID-19. ¿ 2023, The Author(s)