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The Effect of Omega-3 Fatty Acids on Airway Inflammation, Hyperpnea-Induced Bronchoconstriction, and Airway Smooth Muscle Contractility in AsthmaHead, Sally K. 16 March 2012 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Asthma, a chronic inflammatory disease of the airways, affects nearly 25 million Americans. The vast majority of these patients suffer from exercise-induced bronchoconstriction (EIB), a complication of asthma. Although traditionally treated pharmacologically, nutritional strategies provide a promising alternative for managing EIB as the prevalence of asthma may be due in part to changes in diet.
Our objective was to determine the effects of novel nutritional strategies on hyperpnea-induced bronchoconstriction (HIB) in asthmatic individuals. HIB uses rapid breathing to identify EIB in a research or clinical setting. Fish oil, a combination of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docsahexaenoic acid (DHA), has been shown to be effective in suppressing EIB. However, its use in combination with other nutritional supplements, the optimal fish oil formula, and its effect on smooth muscle contractility have not been fully explored.
An in vivo study (study 1) was conducted in individuals with both asthma and HIB to determine whether a combination of fish oil and vitamin C was more effective than either one alone in alleviating HIB. Pulmonary function was significantly improved with both fish oil and the combination treatment but not with vitamin C alone. In study 2, individuals with both asthma and HIB were supplemented with DHA alone since the optimal formula for fish oil has yet to be ascertained; previous in vitro studies have suggested DHA may be the more potent omega-3 fatty acid in fish oil. However, no significant changes in pulmonary function or airway inflammation were seen with DHA supplementation.
For study 3, canine airway smooth muscle tissue was treated with fish oil to determine the in vitro effect of fish oil on smooth muscle contractility. Acute treatment with fish oil relaxed smooth muscle strips that had been contracted with 5-hydroxytryptamine. These minor relaxations in smooth muscle tension with fish oil may represent significant changes at the level of the smaller airways.
These studies have confirmed that fish oil represents a viable treatment modality for asthmatic individuals with EIB and suggest that fish oil may influence airway smooth muscle contractility.
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The role of Pod1/Tcf21 in epicardium-derived cells in cardiac development and diseaseBraitsch, Caitlin M. 17 September 2013 (has links)
No description available.
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Characterizing quinclorac-resistant smooth crabgrass (Digitaria ischaemum) control and possible metabolic mechanisms of resistancePutri, Atikah Dwi 12 May 2023 (has links) (PDF)
Quinclorac controls crabgrass (Digitaria spp.) post-emergence in cool- and warm-season turfgrass. A rate response study revealed that two Mississippi smooth crabgrass (Digitaria ischaemum) species (MSU1 and MSU2) are resistant to quinclorac. Following that, field experiments were carried out to evaluate programmatic approaches to control one of these populations. Despite prior study on quinclorac-resistant weeds, to date, quinclorac-resistant smooth crabgrass and its mechanism of resistance have only been reported once in California. The mechanism of resistance of MSU1 and MSU2 relative to susceptible (SMT) was then investigated. The SMT biotype accumulated three times more cyanide than the resistant populations. Glutathione-S-transferase (GST) activity was evaluated as a possible contributor to non-target site resistance. The GST activity was elevated in the MSU1 and MSU2 populations. These findings suggest a non-target site–based mechanism of resistance involving the accumulation of cyanide. Further research is needed to investigate potential target-site mechanisms of resistance.
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Development of an in vitro model to study the impact of substrate strain on uterine smooth muscle cell hypertrophyMarr, Elizabeth E. 31 May 2022 (has links)
In 2018, 1 in every 10 infants born in the United States was born preterm. The majority of neonatal deaths and nearly a third of infant deaths that occur are linked to preterm birth. Preterm birth is initiated when the quiescent state of the uterus ends prematurely, leading to contractions and parturition beginning as early as 32 weeks, though the origins are not well understood. Tocolytics are pharmaceuticals utilized to postpone preterm labor, but currently only manage to prolong pregnancy for up to 48 hours and have not proven effective in completely preventing preterm delivery. To enable research and discovery of therapeutics with potential to better address preterm birth, the capability to study isolated cell processes of pregnant uterine tissue in vitro is needed. Our development of an in vitro model of the myometrium utilizing uterine myocytes - uterine smooth muscle cells (uSMCs) responsible for contractions - provides a platform to examine the cellular mechanisms of late-stage pregnancy potentially involved in preterm birth. In this thesis, we discuss the optimized culture of uterine SMCs on a flexible polydimethylsiloxane (PDMS) substrate functionalized using a cationic solution, Poly-L-lysine (PLL), followed by extracellular matrix (ECM) protein coating. Using the model we developed, we then exposed this elastic substrate with uterine SMCs to different strain rates in order to investigate the impact of mechanical strain parameters on uterine SMC hypertrophy in the uterus during late-stage pregnancy. It was found that PLL and ECM protein coatings significantly impact cell morphology and density in unstrained substrates. It was also observed that when exposed to strain conditions, strain significantly increased hypertrophic morphological traits in select conditions. These results indicate that both surface and mechanical properties of in vitro systems impact uterine SMC phenotype, offering further understanding of cellular pathways involved in the uterus under mechanical load. / 2024-05-31T00:00:00Z
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Comparing head- and eye direction and accuracy during smooth pursuit in an augmented reality environmentHogler, Marcus January 2019 (has links)
Smooth pursuit is the movement that occurs when the eyes meticulously follow an object in motion. While smooth pursuit can be achieved with a stationary head, it generally relies on the head following the visual target as well. During smooth pursuit, a coordinating vestibular mechanism, shared by both the head and the eyes, is used. Therefore, smooth pursuit can reveal much about where a person is looking based on only the direction of the head. To investigate the interplay between the eyes and the head, an application was made for the augmented reality head-mounted display Magic Leap. The application gathered data of the head and eyes respective movements. The data was analyzed using visualizations to find relationships within the eye-head coordination. User studies were conducted and the eyes proved to be incredibly accurate and the head direction was close to the target at all times. The results point towards the possibility of using head direction as a model for visual attention in the shape of a cone. The users’ head direction was a good indicator of where they put their attention, making it a valuable tool for developing augmented reality applications for head-mounted displays and smart glasses. By only using head direction, a software developer can measure where most of the users’ attention is put and hence optimize the application according to this information. / Följerörelser är det som sker när ögonen noggrant följer ett objekt i rörelse. Följerörelser kan uppnås med ett stationärt huvud, men generellt används även huvudet för att följa det visuella målet. Ögonen och huvudet delar en vestibulär koordineringsmekanism som är aktiv under följerörelser och därför kan enbart huvudrörelser avslöja mycket om var en person har sin uppmärksamhet.För att undersöka samspelet mellan ögonen och huvudet gjordes en applikation för ett augmented reality headsetet Magic Leap. Applikationen samlade in data på ögonrespektive huvudrörelser. Den insamlade datan analyserades med hjälp av visualiseringar för att hitta förhållanden inom ögon-huvud koordinationen.Användarstudier utfördes och ögonen visade sig vara väldigt exakta och huvudets riktning var hela tiden i närheten av målet. Resultatet pekar mot möjligheten att använda huvudriktning som en modell för visuell uppmärksamhet i formen av en kon. Användarnas huvudriktning var en bra indikator på var de hade sin uppmärksamhet, vilket gör den till ett användbart verktyg för utveckling av augmented reality applikationer för headsets och smartglasögon. En mjukvaruutvecklare kan mäta var användarnas uppmärksamhet dras genom att använda huvudriktningen och kan därmed optimera applikationen utefter den informationen.
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Sparse Ridge Fusion For Linear RegressionMahmood, Nozad 01 January 2013 (has links)
For a linear regression, the traditional technique deals with a case where the number of observations n more than the number of predictor variables p (n > p). In the case n < p, the classical method fails to estimate the coefficients. A solution of the problem is the case of correlated predictors is provided in this thesis. A new regularization and variable selection is proposed under the name of Sparse Ridge Fusion (SRF). In the case of highly correlated predictor, the simulated examples and a real data show that the SRF always outperforms the lasso, eleastic net, and the S-Lasso, and the results show that the SRF selects more predictor variables than the sample size n while the maximum selected variables by lasso is n size.
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Calcium-Binding Protein S100A4 Is Upregulated in Carotid Atherosclerotic Plaques and Contributes to Expansive Remodeling / 頚動脈プラークにおいてS100A4発現が亢進し、陽性リモデリングと関連するNagata, Manabu 24 November 2022 (has links)
京都大学 / 新制・論文博士 / 博士(医学) / 乙第13515号 / 論医博第2265号 / 新制||医||1061(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 湊谷 謙司, 教授 石見 拓, 教授 江木 盛時 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
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Role of magnesium ions in the excitation of vascular smooth muscle. Effects of hypermagnesaemia and hypomagnesaemia on drug-induced contractions of mammalian arteries with special reference to the involvement of changed tissue calcium ion concentration or distribution in the observed responses.Asmawi, Mohd. Z. January 1982 (has links)
Studies on the perfused rabbit ear artery preparation showed that
withdrawal of Mg 2+ from extracellular fluid potentiated the responses
to histamine and ATP but not to catecholamines. Similar results were
obtained in [2xCa2+] Krebs solution. Increases in [Mg 2+] decreased
responses to the three agonists to a similar extent. In subsequent
experiments attempts were made to alter the availability of calcium for
contraction induced by these agonists either by changing the [Ca 2+]
of the Krebs solution or by using Ca 2+ influx inhibitors, ouabain and
ryanodine. The effects of these agonists were compared to those
observed when Mg2+ was altered. In general, the results obtained
in perfused rabbit ear artery supported the hypothesis that changes in
extracellular [Mg2+] affect the availability of calcium for contraction
but were not consistent with the suggestion that Mg2+ alters Ca2+ influx.
In a second type of preparation tension responses of superfused
rings of ear artery were studied. Responses to changes in extracellular
[Ca2+] and[ Mg2+] were found to differ slightly from those
obtained in the perfused artery. A simultaneously perfused and
superfused arterial preparation showed that responses to changes in
[ Mg2+] and[Ca2+] were different if the agonist was administered to
the adventitial surface of the vessel rather than via the intimal
surface.
The effects of alterations in extracellular [Mg 2+] were studied in mesenteric arteries from weight matched normotensive and spontaneously
hypertensive rats (SHR). No differences in response to NA or
ATP when extracellular [Mg 2+ ] was either increased or reduced were
observed in the SHR compared to the normotensive animal. However,
a difference in calcium dependence was demonstrated between the two
types of vessels to NA. In contrast to mesenteric arteries, experiments
on aortae from normotensive rats and SHR showed no differences
in the calcium dependence of NA responses between normotensive and
SHR vessels, whereas,
[4xMg2+ ] Krebs solution reduced the responses
of normotensive aorta to NA more than SHR. These results in the
rat were not consistent with the hypothesis that alteration in [Mg 2+]
can be explained in terms of altered calcium availability. Attempts
to increase intracellular cyclic AMP with theophylline showed that
the response to ED50 NA in both mesenteric arteries and aortae from
normotensive were reduced more than SHR.
It is concluded that the effect of changes in extracellular [Mg2+]
on the reactivity of vascular muscle varies depending on the type of
vessel and species of animal from which the vessel is taken. In
addition when all the experimental results are considered, it is not
possible to explain all the actions of altered [ Mg2+ ] simply in
terms of changed calcium availability.
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Evaluation of Novel Techniques to Control Annual Grasses in Intensively Managed Turfgrass SystemsPeppers, John Michael 19 December 2023 (has links)
Annual grassy weeds are problematic in intensively managed turfgrass systems due to a lack of selective and affordable control options. Four projects were conducted from 2020-2023 to evaluate novel techniques for Annual bluegrass (Poa annua L.), goosegrass (Eleusine indica L. Gaertn.), and smooth crabgrass (Digitaria ischaemum Schreb.) control on golf course putting greens or putting green surrounds. Hybrid bermudagrass Cynodon transvaalensis Burtt. Davy. x dactylon L. Pers.) tolerated cumyluron regardless of application timing, endothall when applied during full dormancy, and methiozolin when applied during mid-transition. Methiozolin half-life in the upper 2-cm of 12 hybrid bermudagrass putting greens was approximately 14 days and was prolonged in similar studies by seven orders of magnitude when herbicide was applied to bare ground compared to adjacent Kentucky bluegrass (Poa pratensis L.) turf. In a study conducted in Alabama, California, Florida, and Virginia, methiozolin at labeled use rates applied biweekly controlled smooth crabgrass >80% in creeping bentgrass (Agrostis stolonifera L.) and hybrid bermudagrass turf. Although similar programs also controlled goosegrass, acceptable control required more applications than are allowed on the product label. Targeted application devices (TAD), such as spot sprayers and dabbers that are used for individual plant treatment of escaped weeds, were tested for uniformity of fluid delivery. Fluid output of dabbing devices was highly variable and dependent on reservoir fill level, reservoir air seal, human user, and contact time, but largely independent of peak force exerted during the dabbing event. These studies suggest that new products are available to improve annual grassy weed control in turfgrass systems, but proper application timing and device calibration is important to achieve best results. / Doctor of Philosophy / Annual grasses are difficult to control in "high-end" golf turf because few herbicides can be safely used near greens and key weeds have become resistant to the most common products. Several new products were tested for safety on hybrid bermudagrass greens. Methiozolin (PoaCure) was safe for use after post-dormancy greenup, endothall was safe when used while turf was still dormant, and cumyluron was safe regardless of application timing. The duration of preemergence weed control with methiozolin is reduced as temperatures increase and in turfgrass compared to bare ground systems. Half of the methiozolin product will dissipate in 14 days or less when applied to hybrid bermudagrass putting greens or Kentucky bluegrass lawns in spring. Methiozolin controlled smooth crabgrass for the entire season in several Southeastern states, but goosegrass control was slightly below acceptable levels when the product was used within annual dose restrictions. Applicators, such as dabbers and spot sprayers, that are used to treat individual plants improve turf safety and reduce chemical cost, but these devices had not been previously tested for uniformity of fluid output. Studies found that these devices can vary in output by several orders of magnitude depending on the type of devices used, the person using the device, and duration of contact with the turf as the user presses a dabbing device over a weed. Within-device errors were equally problematic and governed by the amount of downward pressure exerted by the fluid contained in the device reservoir. For every 10% of fluid capacity added, fluid dispense rate increases approximately 33%. When the air seal of the fluid fill cap is broken, fluid output approximately doubles compared to when this seal is maintained because loss of vacuum increases downward force of the fluid column. These studies suggest that new products are available to improve annual grassy weed control in ornamental turf, but proper application timing and device calibration is important to achieve best results.
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Adenosine and Vascular HomeostasisSimard, Trevor 30 May 2023 (has links)
Despite advancements in percutaneous coronary intervention, stents are still limited by a 2% annual rate of in-stent restenosis (ISR) related to neointimal (NI) tissue proliferation. Efforts to prevent ISR formation remain the focus of ongoing work. Adenosine (ADO) is a purine nucleoside with integral roles in vascular homeostasis, though it has limited clinical application. ADO signals primarily via four receptors with ADO receptor-A2B (ADOR-A2B) considered to play an integral role in vascular healing. Dipyridamole (DP) is a commercially approved therapy known to improve vascular events and modulate adenosine biology. Our objectives with this study included (i) assessing whether ADO could serve as a biomarker of cardiac events; (ii) determine if DP could mitigate NI formation in a pre-clinical stent model; and, (iii) quantify the mechanisms of DP-related vasculoprotection, specifically related to ADOR-A2B.
We assessed the analytic and biologic variability of circulating ADO levels in humans and demonstrated that circulating ADO was not predictive of cardiac events at one year following invasive coronary angiography. We then assessed whether modulation of adenosine biology with DP had therapeutic efficacy in a pre-clinical model. Utilizing meta-analysis, we confirmed the sustained effects of DP on vascular patency rates in both pre-clinical and clinical studies. We refined a pre-clinical rabbit model of stent implantation with assessment of stent healing by intravascular optical coherence tomography – with excellent translation to clinical observations. We then assessed DP in a pre-clinical model, demonstrating reduction in ISR and improved stent healing with DP compared to control. Last, we sought to elucidate the mechanisms behind the observed DP effects, specifically related to ADOR-A2B. In vivo, DP therapy demonstrated reduced NI smooth muscle cell (SMC) content. In vitro assessment of DP demonstrated dose-dependent inhibition of SMC proliferation and migration with alteration of SMC phenotypic switching, while selective modulation of ADOR-A2B and ADOR-A2B knockdown support an ADOR-A2B-mediated component to the observed DP effects.
Adenosine biology is integral to vascular homeostasis. In humans, circulating adenosine levels in humans are not predictive of one year cardiovascular events. However, DP may improve vascular healing post stent implantation and warrants clinical evaluation for stent healing. The observed DP benefits may, in part, stem from ADOR-A2B modulation. ADOR-A2B is a viable target for assessment of small molecule modulation as a novel therapeutic target to improve vascular outcomes.
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