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Assessment of the cell cycle proteins Cdc7 and PCNA as markers of colon carcinogenesis in obese and lean ratsWood, Katherine January 2009 (has links)
Obesity increases the risk of colon cancer as well as the expression of many cancer markers, ostensibly due to the interaction between insulin resistance and adipocyte production of hormones, mitogens and cytokines which collaborate to enhance proliferation signaling and impair the DNA damage response. Cdc7 and PCNA are both proteins involved in the DNA damage response as well as DNA replication. Both have also been shown to be upregulated in human tumours. To assess Cdc7 and PCNA roles during the DNA damage response in obese and lean animals, we administered azoxymethane (AOM), a colon-specific carcinogen, to obese and lean rats. Cdc7 and PCNA levels in colonic mucosal protein extracts from obese Zucker rats were compared with those from their lean counterparts. Significant differences were seen between lean and obese animals 3 hours post-AOM (lean Cdc7 levels > obese Cdc7 levels) and 24 hours post-AOM (lean PCNA levels > obese PCNA levels). This result suggests an impaired checkpoint response in obese animals relative to lean animals and supports a previously reported early role for Cdc7 in the checkpoint signaling cascade relative to a later role of PCNA in DNA damage repair. At the time tumours appeared (32 weeks post-AOM), colonic mucosal Cdc7 levels of obese rats exceeded that of their lean counterparts, suggesting that the obese metabolic environment causes upregulation of Cdc7 in obese rat epithelia. Cdc7 and PCNA levels were then compared between tumours and mucosa in obese and Sprague Dawley rats. Tumour Cdc7 levels were upregulated relative to mucosal levels in more samples than tumour PCNA levels, suggesting Cdc7 may be a more sensitive tumour marker. No significant differences in Cdc7 levels were seen between obese tumours and mucosa, likely due to elevation of obese mucosal Cdc7 levels. However, Sprague Dawley (non-obese) rats showed significantly higher Cdc7 and PCNA levels in tumours than mucosa, consistent with previous studies in human tissues. These results suggest that Cdc7 may be a more sensitive tumour marker than PCNA, but that its utility as a biomarker of colon cancer is dependent on the metabolic state (leanness) of the individual.
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An Assessment of Pyridoxine as a Biological Response Modifier During Colon CarcinogenesisKular, Aneta 04 October 2007 (has links)
The main objective of this proposal was to investigate the effect of vitamin B6 on colon carcinogenesis in vivo. Two in vivo studies were conducted to determine the role of vitamin B6 as a biological modifier of colon carcinogenesis. It is hypothesized that vitamin B6 may serve as an antioxidant in vivo and will modulate colon carcinogenesis. In the first study, a 2X3 factorial experimental design was used to determine if three different levels of vitamin B6, classified as low, normal and high in conjunction with two different levels of protein intake, classified as normal or high, will affect post-initiation stages of colon carcinogenesis, in Sprague-Dawley rats. Male Sprague-Dawley male were injected with azoxymethane for two weeks (15mg/kg/week) and then one week later they were allocated to different dietary treatment groups. After eight weeks, the effects of dietary treatment on hematological status, oxidative stress markers and antioxidant enzymes, as well as enumeration of preneoplastic lesions, aberrant crypt foci (ACF), were evaluated. The lowest level of vitamin B6 intake with a high protein diet reduced the growth and development of ACF. Vitamin B6 had no significant effect on the oxidative stress markers. The level of protein was an important variable in modulating the levels of 3-nitrotyrosine and 8-OH-DG which were lower in high protein groups than normal protein counterparts.
The objective of the second study was to investigate if a supraphysiological (5 fold higher than normal level) dosage of vitamin B6 could have an antioxidant effect in a metabolically compromised state like obesity and thereby lower the risk of colon cancer. Female Zucker obese (Zk-OB) rats received normal (Zk-OBN, 7 mg/kg) or high (Zk-OBH, 35 mg/kg) vitamin B6 (Pyridoxine-HCl) diets two weeks prior to, during and six weeks following injection with colon carcinogen AOM. The effects of supplemental vitamin B6 on hematological status, oxidative stress markers and antioxidant enzymes, as well as enumeration of ACF were carried out. High intake of vitamin B6 significantly lowered liver weights and plasma cholesterol compared to the normal intake (p≤0.05). Zk-OBH rats had significantly reduced number of ACF compared to Zk-OBN (p≤0.05). Hepatic GSH increased in the ZK-OBH group with a concomitant decrease in GPx activity. The findings demonstrate that in Zucker Obese rats, a high B6 intake augmented the antioxidant potential and decreased sensitivity to colon carcinogenesis. These findings suggest that high vitamin B6 plays an important therapeutic role in the compromised state of obesity.
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Assessment of the cell cycle proteins Cdc7 and PCNA as markers of colon carcinogenesis in obese and lean ratsWood, Katherine January 2009 (has links)
Obesity increases the risk of colon cancer as well as the expression of many cancer markers, ostensibly due to the interaction between insulin resistance and adipocyte production of hormones, mitogens and cytokines which collaborate to enhance proliferation signaling and impair the DNA damage response. Cdc7 and PCNA are both proteins involved in the DNA damage response as well as DNA replication. Both have also been shown to be upregulated in human tumours. To assess Cdc7 and PCNA roles during the DNA damage response in obese and lean animals, we administered azoxymethane (AOM), a colon-specific carcinogen, to obese and lean rats. Cdc7 and PCNA levels in colonic mucosal protein extracts from obese Zucker rats were compared with those from their lean counterparts. Significant differences were seen between lean and obese animals 3 hours post-AOM (lean Cdc7 levels > obese Cdc7 levels) and 24 hours post-AOM (lean PCNA levels > obese PCNA levels). This result suggests an impaired checkpoint response in obese animals relative to lean animals and supports a previously reported early role for Cdc7 in the checkpoint signaling cascade relative to a later role of PCNA in DNA damage repair. At the time tumours appeared (32 weeks post-AOM), colonic mucosal Cdc7 levels of obese rats exceeded that of their lean counterparts, suggesting that the obese metabolic environment causes upregulation of Cdc7 in obese rat epithelia. Cdc7 and PCNA levels were then compared between tumours and mucosa in obese and Sprague Dawley rats. Tumour Cdc7 levels were upregulated relative to mucosal levels in more samples than tumour PCNA levels, suggesting Cdc7 may be a more sensitive tumour marker. No significant differences in Cdc7 levels were seen between obese tumours and mucosa, likely due to elevation of obese mucosal Cdc7 levels. However, Sprague Dawley (non-obese) rats showed significantly higher Cdc7 and PCNA levels in tumours than mucosa, consistent with previous studies in human tissues. These results suggest that Cdc7 may be a more sensitive tumour marker than PCNA, but that its utility as a biomarker of colon cancer is dependent on the metabolic state (leanness) of the individual.
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Studies of the IMF and dayside reconnection-driven convection seen by PolarDARNYan, Xi 01 April 2010 (has links)
The original objectives of this thesis were to use the new PolarDARN radars to study the convection patterns at high latitudes and to attempt to explain them in terms of reconnection. Because the IMF is important in reconnection, studies of the Interplanetary Magnetic Field (IMF) components Bx, By and Bz were done. The study showed that <|Bz|> was lower by 21.5% than <|By|> from Jan. 2006 to Dec. 2008, so By was expected to play an important role in reconnection. The IMF, spiral angle, and the amount of warping of the solar magnetic field in interplanetary space decreased slightly during this 36-month period. The decrease in IMF was a more sensitive indicator of the solar minimum than the decrease in the 10.7 cm solar microwave flux.<p>
A solar magnetic sector boundary study from the Jan 1, 2007 Dec 31, 2008 interval showed the occurrence of four or two sectors in a synodic solar rotation cycle. A sector boundary crossing frequently takes place in less than 3 hours. The transition from four sectors to two sectors is surprisingly smooth, in that no interruption in the 27-day synodic period occurs. A superposed epoch analysis of solar wind speed near sector boundary crossings showed a speed minimum about half a day before the crossing, and a maximum about two days after the crossing. The standard deviation reached a minimum at about the same time as the velocity. The sector boundary study also showed that, since Dec. 2007, there were six roughly 27-day synodic solar rotation cycles near spring equinox when away field dominated, and that the following seven 27-day cycles close to the autumnal equinox were dominated by toward field. This is consistent with the quasi-sinusoidal annual magnetic sector polarity oscillations that occur for about three years during solar minimum. These oscillations are due to the mainly dipolar magnetic field which is roughly aligned with the Suns axis, tilted 7.25° from the normal to the ecliptic plane. The three-year oscillation for the present minimum between Solar Cycles 23 and 24 appeared to begin in Dec. 2007. For the past four solar minima, an El Nino event has occurred during the last of the three oscillations, and the El Nino and sinusoidal magnetic oscillation ended together. The new solar cycle began about 6 months before that.
During the past eight years, a new 3D topological null-separator formulation of magnetic reconnection and its effect on convection has been led by Dr. M. Watanabe in ISAS at the University of Saskatchewan. This formulation includes two types of interchange reconnection (Russell and Tanaka) as well as the traditional Dungey reconnection. For conditions when the IMF clock angle was within 30° of a Bz+ dominant convection, the new reconnection model shows that the convection can be driven strictly by the two types of interchange reconnection. The model predicts the existence of a reciprocal cell on closed field lines and an interchange merging cell surrounding an interior lobe cell. The construction of the PolarDARN radars at Rankin Inlet and Inuvik, completed in December, 2007, allowed polar cap convection to be measured for predominantly Bz+ conditions. The existence of the two predicted features was confirmed. This also required that satellite data be analyzed to determine the location of the open-closed-field-line-boundary (OCFLB). Several PolarDARN studies are represented to show convection for different IMF clock angles and seasons.
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A Study on the Deformation and Stress Distributions of ACF/ACA on the Flip-Chip PackagingLin, Yen-hong 03 September 2006 (has links)
In this thesis, the contact behavior of the conduct particles in the anisotropic conductive film (ACF) packaging process is investigated. The thermal elastic-plastic finite element (FE) model is employed to simulate the contact process. The commercial MARC finite element method package is used in this work. Two contact models of the ACF packaging are studied : the single particle and the multiple-particles models. In the single particle model a simple axial symmetric FE model is used to simulate the variation of elastic-plastic deformations during packaging process. The effect of coating thickness on the contact deformation is discussed.
To explore the effect of particle distribution on the contact deformation and the conduct behavior in the ACF packaging, the multiple-particles 3D model has also been studied. However, to overcome the computing difficulties introduced from huge degrees of freedom, the equivalent nonlinear springs are employed to stand for some conductive particles. The effect of particle distribution and particle parameters on the conductive behavior are studied. Results indicate that the conductive particle parameters may affect the conductive characteristics significantly in the ACF packaging process.
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Postharvest irradiation treatment effect on grapefruit functional components and their role in prevention of colon cancerVanamala, Jairam Krishna Prasad 01 November 2005 (has links)
This dissertation examines the effects of postharvest treatment and processing on biologically active compounds of orange juice, and ??Rio Red?? grapefruit and their ability to prevent chemically induced colon cancer in rat model. The first study evaluated the differences in flavonoid content of commercial ??made from concentrate?? (MFC) orange juices and ??not from concentrate?? (NFC) orange and grapefruit juices. Total flavonoid content of MFC orange juices (53 mg/100 mL; n = 12) was significantly (P ≤ 0.05) higher than NFC orange juices (36.5 mg/100 mL; n = 14).
The second study investigated the ionizing radiation and storage effects on bioactive compounds and quality of ??Rio Red?? grapefruit. Results showed that storage and irradiation significantly (P ≤ 0.05) affected the bioactive compounds in grapefruit, however, the effect of storage was prominent. The third study examined the influence of irradiation and freeze drying on bioactive compounds of grapefruit. Irradiation of grapefruit prior to freeze drying resulted in enhanced
(P ≤ 0.05) flavonoid content (naringin and narirutin). Freeze drying markedly reduced (P ≤ 0.05) lycopene content. Freeze drying and irradiation reduced (P ≤ 0.05) volatile compounds (d-limonene and myrcene), with the exception of
ethanol.
In the fourth study suppression of colon cancer development in Sprague Dawley rats by natural and irradiated grapefruits and their functional compounds, naringin and limonin, were evaluated.The total number of aberrant crypts (AC; P = 0.02), number of high multiplicity AC foci (ACF; P = 0.01), and proliferative index (P = 0.02) were lower and apoptosis (P = 0.02) was higher in azoxymethane (AOM) injected rats on experimental diets. However, only natural grapefruit and limonin only suppressed AOM induced expansion (P = 0.008) of proliferative zone and also enhanced apoptosis more effectively than other experimental diets indicating that natural grapefruit and limonin may serve as better chemopreventive agents compared to IGFPP and naringin.
The present study indicates that postharvest quarantine doses of irradiation slightly alter composition of bioactive compounds and in turn marginally reduce the chemopreventive ability of grapefruit against the promotion stage of colon cancer. These results warrant the necessity of testing the impact of post harvest treatments on fruits and vegetables chemopreventive ability.
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Webbplats i WordPress : Modulär uppbyggnad med ACF pluginHjemdahl, Moa January 2021 (has links)
The report is about the project with the aim of building a front-end solution on a website in the WCMS WordPress for the customer Photon Sports through the full-service agency Oh My. The website, which will be built from an already developed design, will showcase the company's product and include a function for interested parties to sign up for a waiting list. The structure must be made so flexible in terms of content that the customer can manage and update the website through the WordPress admin interface after the completed project. The modules and other elements that will build the subpages on the website are created with the WordPress plugin Advanced Custom Fields (ACF), self-written code in the languages HTML and PHP, CSS with Tailwind for styling, JS for functionality, and with WordPress' functions for mail and menus. The project results in a finished solution that is functional, responsive, available in different formats, and that lives up to the design requirements. The content of the website is flexible for the customer to handle and the basic idea of the WCMS comes in handy for both the customer and the developer, even if the usability of the admin interface does not always live up to its full potential. Results of technical tests such as validation of code and the speed of the website show points that do not reach the highest level but are concluded not to be fixed due to possibility or choice. The entire work with the project has shown lessons in method and approach, thoughts on possible further solutions to usability, and reflection on ethical and social parts of the project concerning accessibility and laws. / Rapporten handlar om projektet med syftet att genom fullservicebyrån Oh My bygga en frontend lösning på en webbplats i WCMSet WordPress till kunden Photon Sports. Webbplatsen som ska byggas från en redan framtagen design ska visa upp företagets produkt och innehålla funktion för intressenter att skriva upp sig på en väntelista. Uppbyggnaden ska göras så pass flexibel innehållsmässigt att kunden ska själv kunna efter avslutat projekt hantera och uppdatera webbplatsen genom WordPress admingränssnitt. Modulerna och övriga element som ska bygga upp undersidorna på webbplatsen skapas med WordPress pluginet Advanced Custom Fields(ACF), egenskriven kod i språken HTML och PHP, CSS med Tailwind för styling, JS för funktionalitet, och med WordPress funktioner för mail och menyer. Projektet resulterar i färdig lösning som är funktionell, responsiv, tillgänglig i olika format och som lever upp till designens krav. Innehållet i webbplatsen är flexibelt för kunden att hantera och grundtanken med WCMSet kommer till sin användning för likväl kunden som utvecklaren även om användbarheten i admingränssnittet inte alltid lever upp till sin fulla potential. Resultat på tekniska tester som validering av kod och webbplatsens hastighet visar på punkter som inte når högsta nivå men får slutsaten att ej åtgärdas på grund av möjlighet eller val. Hela arbetet med projektet har visat på lärdomar i metod och förhållningssätt, tankar om möjliga vidare lösningar på användbarhet och reflektion över etiska och sociala delar i projektet som rör tillgänglighet och lagar.
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Brukande eller bevarande av den fjällnära svenska skogen? : En studie av hur olika miljömål prioriteras av våra riksdagspartierKågström, Olivia January 2024 (has links)
Svensk skogspolitiks övergripande mål är jämnt uppdelat mellan miljömålet och produktionsmålet. Det gäller även den fjällnära skogen vilken besitter hög biologisk mångfald, samt stora arealer produktiv skogsmark vilket enligt skogspolitikens mål ska vara jämnt uppdelade. Skiftningar mellan prioriterat miljömål och produktionsmål har däremot indikerats de senaste 20 åren vilket lyfter upp studiens övrigripande forskningsfrågor angående hur svensk skogspolitik styrs och hur den fjällnära skogens nära framtid kan se ut i samband med nya ekonomiska ersättningar presenterade i proposition 2021/22:207. Denna studie undersöker de svenska riksdagspartierna i frågan om miljömål och produktionsmål i en svensk skogspolitisk policyförändring med hjälp av ACF. Genom att undersöka och förklara riksdagspartiernas övertygelser och koalitioner i samband med kammardebatten om proposition 2021/22:207 angående ersättning där ansökan om avverkning nekats i fjällnära skog ämnar studien undersöka och förklara drivkrafterna bakom ett skogspolitiskt beslut med viljan att skapa ökad förståelse angående hur svensk skogspolitik styrs och hur det kan påverka skogens nära framtid. Genom att bryta ner och analysera partiernas normativa och empiriska ”policy core beliefs” genom en tematisk innehållsanalys identifierar studien motstående koalitioner i fråga om brukandet eller bevarandet av den fjällnära skogen gällande hotbild, förvaltning och styrmedel. Därmed bidrar studien till en ökad förståelse av hur partiernas övertygelser kan spegla policyförändring i en skogspolitisk fråga och hur det i sin tur kan påverka den fjällnära skogens nära framtid.
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Mechanisms of transcriptional repression by pure antiestrogens in breast cancer cellsTraboulsi, Tatiana 08 1900 (has links)
No description available.
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Long Term Forecasting of Industrial Electricity Consumption Data With GRU, LSTM and Multiple Linear RegressionBuzatoiu, Roxana January 2020 (has links)
Accurate long-term energy consumption forecasting of industrial entities is of interest to distribution companies as it can potentially help reduce their churn and offer support in decision making when hedging. This thesis work presents different methods to forecast the energy consumption for industrial entities over a long time prediction horizon of 1 year. Notably, it includes experimentations with two variants of the Recurrent Neural Networks, namely Gated Recurrent Unit (GRU) and Long-Short-Term-Memory (LSTM). Their performance is compared against traditional approaches namely Multiple Linear Regression (MLR) and Seasonal Autoregressive Integrated Moving Average (SARIMA). Further on, the investigation focuses on tailoring the Recurrent Neural Network model to improve the performance. The experiments focus on the impact of different model architectures. Secondly, it focuses on testing the effect of time-related feature selection as an additional input to the Recurrent Neural Network (RNN) networks. Specifically, it explored how traditional methods such as Exploratory Data Analysis, Autocorrelation, and Partial Autocorrelation Functions Plots can contribute to the performance of RNN model. The current work shows through an empirical study on three industrial datasets that GRU architecture is a powerful method for the long-term forecasting task which outperforms LSTM on certain scenarios. In comparison to the MLR model, the RNN achieved a reduction in the RMSE between 5% up to to 10%. The most important findings include: (i) GRU architecture outperforms LSTM on industrial energy consumption datasets when compared against a lower number of hidden units. Also, GRU outperforms LSTM on certain datasets, regardless of the choice units number; (ii) RNN variants yield a better accuracy than statistical or regression models; (iii) using ACF and PACF as dicovery tools in the feature selection process is unconclusive and unefficient when aiming for a general model; (iv) using deterministic features (such as day of the year, day of the month) has limited effects on improving the deep learning model’s performance. / Noggranna långsiktiga energiprognosprognoser för industriella enheter är av intresse för distributionsföretag eftersom det potentiellt kan bidra till att minska deras churn och erbjuda stöd i beslutsfattandet vid säkring. Detta avhandlingsarbete presenterar olika metoder för att prognostisera energiförbrukningen för industriella enheter under en lång tids förutsägelsehorisont på 1 år. I synnerhet inkluderar det experiment med två varianter av de återkommande neurala nätverken, nämligen GRU och LSTM. Deras prestanda jämförs med traditionella metoder, nämligen MLR och SARIMA. Vidare fokuserar undersökningen på att skräddarsy modellen för återkommande neurala nätverk för att förbättra prestanda. Experimenten fokuserar på effekterna av olika modellarkitekturer. För det andra fokuserar den på att testa effekten av tidsrelaterat funktionsval som en extra ingång till RNN -nätverk. Specifikt undersökte den hur traditionella metoder som Exploratory Data Analysis, Autocorrelation och Partial Autocorrelation Funtions Plots kan bidra till prestanda för RNN -modellen. Det aktuella arbetet visar genom en empirisk studie av tre industriella datamängder att GRU -arkitektur är en kraftfull metod för den långsiktiga prognosuppgiften som överträffar ac LSTM på vissa scenarier. Jämfört med MLR -modellen uppnådde RNN en minskning av RMSE mellan 5 % upp till 10 %. De viktigaste resultaten inkluderar: (i) GRU -arkitekturen överträffar LSTM på datauppsättningar för industriell energiförbrukning jämfört med ett lägre antal dolda enheter. GRU överträffar också LSTM på vissa datauppsättningar, oavsett antalet valenheter; (ii) RNN -varianter ger bättre noggrannhet än statistiska modeller eller regressionsmodeller; (iii) att använda ACF och PACF som verktyg för upptäckt i funktionsvalsprocessen är otydligt och ineffektivt när man siktar på en allmän modell; (iv) att använda deterministiska funktioner (t.ex. årets dag, månadsdagen) har begränsade effekter på att förbättra djupinlärningsmodellens prestanda.
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