827 resultados para Membrane anchoring lipids
Resumo:
Reports remain insufficient on whether and how prostate-specific membrane antigen (PSMA) can influence in vivo osseous metastasis of prostate cancer (PCa). In the present study, the authors induced stable expression of PSMA in mouse PCa cell line RM-1. In vivo osseous metastasis was induced in 37 6-week-old female C57BL/6 mice weighing 22.45 ± 0.456 g. RM-1 cells were actively injected into the femoral bone cavity, leading to bilateral dissymmetry of bone density in the femoral bone. Tumor cells were also detected in bone tissue by pathological examination. The impact on bone density was demonstrated by the significant difference between animals injected with RM-PSMA cells (0.0738 ± 0.0185 g/cm²) and animals injected with RM-empty plasmid cells (0.0895 ± 0.0241 g/cm²). The lytic bone lesion of the RM-PSMA group (68.4%) was higher than that of the control group (27.8%). Immunohistochemistry showed that the expression of both vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) was distinctly higher in the RM-PSMA group than in the control group, while ELISA and Western blot assay indicated that VEGF and MMP-9 were higher in the RM-PSMA group compared to the control group (in vitro). Thus, the present study proposed and then confirmed for the first time that PSMA can promote in vivo osseous metastasis of PCa by increasing sclerotic destruction of PCa cells. Further analyses also suggested that PSMA functions positively on the invasive ability of RM-1 by increasing the expression of MMP-9 and VEGF by osseous metastases in vivo
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The P1.HTR cell line includes highly transfectable cells derived from P815 mastocytoma cells originating from mouse breast tissue. Despite its widespread use in immunogenic studies, no data are available about the behavior of P1.HTR cells in the chick embryo chorioallantoic membrane model. The objective of the present investigation was to study the effects of P1.HTR cells implanted on the chorioallantoic membrane of chick embryos. We inoculated P1.HTR cells into the previously prepared chick embryo chorioallantoic membrane and observed the early and late effects of these cells by stereomicroscopy, histochemistry and immunohistochemistry. A highly angiotropic and angiogenic effect occurred early after inoculation and a tumorigenic potential with the development of mastocytoma keeping well mast cells immunophenotype was detected later during the development. The P1.HTR mastocytoma cell line is a good tool for the development of the chick embryo chorioallantoic membrane mastocytoma model and also for other studies concerning the involvement of blood vessels. The chick embryo chorioallantoic membrane model of mastocytoma retains the mast cell immunophenotype under experimental conditions and could be used as an experimental tool for in vivo preliminary testing of antitumor and antivascular drugs.
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The effects of guar gum derived from the endosperm of Cyamopsis tetragonoloba (75% soluble fiber, 7.6% insoluble fiber, 2.16% crude protein, 0.78% total lipids, 0.54% ash and 9.55% moisture) on diabetic rats were studied concerning food intake, body weight gain, blood serum cholesterol, triacylglycerols, glucose, LDL-, and HDL-cholesterol concentrations. The effect of gum on indexes of protein absorption and utilization was also investigated. Diets containing 0%, 10% and 20% (w/w) guar gum were fed to diabetic rats for 28 days. In spite of the fact that diabetes elevated blood lipids in all animals, guar gum diet significantly decreased (p <0.05) serum concentrations of cholesterol and triacylglycerols. Furthermore, a concomitant increase in HDL-cholesterol with a substancial elevation of the HDL/LDL cholesterol ratio was found. The most significant result in this assay was the drastic reduction of blood glucose in diabetic rats treated with guar gum diet. The gum promoted a general improvement in the condition of the diabetic rats, in body weight gain and indexes of protein absorption and utilization. The results of this research suggest that guar gum, at concentrations equal to or higher than 10%, should be effective in the treatment of hypercholesterolemia and diabetes, in humans.
Resumo:
Avhandlingen handlar om pappers- och membranbaserad jonmodulerad elektronik. Målet med forskningen har varit att utveckla billig, miljövänlig och brännbar elektronik, som kan användas i vardagliga engångsprodukter. Baskomponenterna som utvecklas och presenteras i avhandlingen är transistorer och kondensatorer. Mer komplicerad logisk kretselektronik demonstreras också med hjälp av dessa komponenter. Substraten som utnyttjas vid framställningen av dessa elektroniska komponenter är papper och membran. Dessa substrat är flexibla, hållbara, billiga, miljövänliga, etc. och därför väl anpassade för befintliga tryckteknologier. Själva baskomponenterna framställs sedan på dessa substrat genom att trycka flera skikt på varandra, där varje enskilt skikt är ett individuellt material. Detta är möjligt eftersom de organiska materialen som används i dessa komponenter är upplösta i ett lösningsmedel och kan därmed tryckas på samma sätt som ett vanligt bläck. Ett tredimensionellt objekt kan på detta sätt framställas. I avhandlingen presenteras flera olika typer av transistorer, men den gemensamma nämnaren bland dessa är att isolatorn är en jonledare. Denna, ganska ovanliga, transistormodellen har den stora fördelen att lågspänningskomponenter kan relativt enkelt framställas. Det som är speciellt med våra transistorer är att vi har använt miljövänliga jonledare. Detta, bl.a., leder till att våra komponenter visar både god prestanda, tillika som de är miljövänliga. I avhandlingen demonstrerar vi även tryckta superkondensatorer, en motsvarighet till laddningsbara batterier, konstruerade på papper med aktiverat kol och miljövänliga jonledare. De mest komplicerade logiska kretsar som demonstreras i denna avhandling är ring-oscillatorer och 1-bits-minnen konstruerade på papper. --------------------------------------------- Väitöskirja käsittelee paperille ja polymeerikalvolle tulostettua ionimoduloitua elektroniikkaa. Tutkimuksen tavoitteena oli kehittää edullista, ympäristöystävällistä ja polttokelpoista elektroniikkaa, jota voidaan käyttää esim. tavanomaisissa kertakäyttötuotteissa. Väitöskirjassa esitellään erilaisia transistoreita ja kondensaattoreita. Näitä elektronisia peruskomponentteja käyttäen demonstroidaan myös monimutkaisempia loogisia piirejä. Komponenttien valmistuksessa alustana käytettiin paperia ja polymeerikalvoa. Valitut alustat ovat joustavia ja kestäviä, ja ovat siksi hyvin yhteensopivia olemassa olevien tulostusmenetelmien kanssa. Peruskomponentit valmistettiin tulostamalla eri materiaaleja päällekkäin. Komponenteissa käytettävät orgaaniset aineet ovat liuenneessa muodossa musteessa, joka voidaan tulostaa samalla periaatteella kuin mikä tahansa normaali muste. Tällä menetelmällä voidaan valmistaa myös kolmiulotteisia tuotteita. Väitöskirjassa esitellään useita erityyppisiä transistoreita, joissa yhdistävänä tekijänä on ionisesti johtava eriste. Tällaista suhteellisen harvinaista transistorityyppiä käyttämällä voidaan mahdollistaa matala-jännitteisten komponenttien yksinkertainen valmistus. Valmistettujen transistoreiden etu on ionisten nesteiden ympäristöystävällisyys. Elektroniset komponentit ovat täten hyviä suorituskyvyltään, mutteivät haitallisia ympäristölle. Väitöskirjassa demonstroidaan myös tulostettujen superkondensaattoreiden, eli ladattavien paristojen vastineiden, valmistus paperille aktiivihiiltä ja ionisia nesteitä käyttäen. Kaikkein monimutkaisimmat loogiset piirit, jotka tässä väitöskirjassa esitellään, ovat rengasoskillaattorit sekä 1-bittinen paperille valmistettu muisti.
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The main goal of the present research was to evaluate the physical properties of blends of lard and soybean oil modified by enzymatic interesterification catalyzed by two different commercial (microbial) lipases, viz. from Candida cylindracea (AY30TM) and from Mucor circinelloides (M10TM). Pure lard exhibited a softening point of ca. 31.8 °C before interesterification, and this value shifted towards 29.1 °C after interesterification by AY30 lipase and towards 28.8 °C after interesterification by M10 lipase The interesterified lard exhibited lower consistency after reaction with both lipases, and this decrease was more pronounced for the reaction catalyzed by M10 lipase. This result was most likely due to the sn-1,3-specificity of M10 lipase. Pure lard displayed a lower SFC after interesterification, and M10 lipase proved to be more effective than AY30 lipase. The non-interesterified lard had a SFC of 31.3% at 10 °C, which was reduced to 23.8 and 19.9% after interesterification with AY30 lipase and M10 lipase, respectively. The lard and soybean oil blends were affected by the enzymatic interesterification and dilution with soybean oil.
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Brazil is the second soybean (Glycine max L. Merrill) producer and exporter in the world. In 2005, soybean cultivated in the southeastern region of the country suffered drought stress imposed by adverse high temperatures and low humidity during its reproductive stage. Little information is available regarding the effect of drought stress on the quality of grains. In this study chemical and biochemical characteristics of five soybean samples belonging to three different cultivars grown under drought stress were evaluated. The samples did not meet standards for marketing and contained high amounts of green seeds. Grains were analyzed for appearance, 100 seed weight, humidity, water activity, proteins, lipids, lipoxygenase 1 activity, peroxides, and pigment contents after harvest and after 20 months of storage at room temperature. Acidity was measured also after 30 months of storage. The values of water activity and humidity were 0.6-0.7 and 8.7-11.9%, respectively, and they did not change during storage time, but there was an increase in acidity, which alludes to lipase activity. The activity of lipoxygenase 1 was greatly affected. Immediately after harvest, the green pigments were represented mainly by pheophytin a, followed by pheophytin b, small quantities of chlorophyll b and chlorophyll a, and traces of other chlorophyll derivatives. After 20 months of storage almost all green pigments had disappeared. Drought stress probably enhanced membrane permeability, which led to a lower pH and promoted transformation of chlorophylls to pheophytins.
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The objective of this work was to evaluate the influence of diets containing different lipid sources on eggs quality during refrigerated storage, on yolk fatty acid composition, and on cholesterol in the yolk. Four diets were used containing Soy Oil (SO), Sunflower Seed (SS), and Meat and Bone Meal + Soy Oil (MBM + SO) or Meat and Bone Meal + Tallow (MBM + TA). The experiment followed a factorial design 4 × 3 with four dietary treatments and three storage times. The eggs were stored at 4 °C for 0, 30, and 60 days. The collected eggs were analyzed for egg weight loss, Haugh units, yolk moisture, yolk lipid oxidation, and cooked yolk firmness. Refrigerated storage reduced Haugh units, and increased yolk moisture. Sixty days of storage time reduced the firmness of hard-cooked yolk. There was an interaction between dietary treatment and storage time for egg weight loss and lipid oxidation. With regard to yolk fatty acid profile, MBM + TA diet increased the contents of palmitic and palmitoleic acids. The levels of oleic and arachidonic acids were higher in yolks from birds fed with SS diet. Linoleic acid level was higher in the yolk from treatment with SO diet. Diets containing MBM + SO induced higher levels of docosahexaenoic acid. Yolk cholesterol content was reduced with the inclusion of SS in the diet. Therefore, the type of lipid present in the diet and refrigerated storage for 60 days at 4 °C can affect the egg quality.
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This study evaluated the nutritional value of sesame and flaxseed oils and their effects on the lipid and glucose profile of rats fed diets containing different fat combinations. Fatty acid composition, refractive index, and iodine and saponification values were analyzed to characterize the oils. In the biological assay, Wistar rats were fed different diets, whose fat composition consisted of varying combinations of flaxseed oil, sesame oil, and animal fat. The primary constituents of the sesame oil were oleic (28.6%), linoleic (28.4%), and lauric acid (14.6%); for the flaxseed oil they were alpha-linolenic (39.90%), oleic (17.97%) and linoleic acid (12.25%). The iodine and saponification values of the oils were within the reference range. Rats fed flaxseed oil-based diets had the lowest serum cholesterol values, whereas rats fed diets with flaxseed oil + sesame oil + animal fat had the highest glucose levels. HDL levels decreased significantly with flaxseed oil. Sesame and flaxseed oils are sources of polyunsaturated fatty acids (PUFA), and the flaxseed oil-based diet had a hypocholesterolemic effect, whereas sesame oil showed oxidative stability since it contains high levels of monounsaturated and saturated fatty acids.
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Lipids were extracted from Chlorella algae with supercritical hexane. The high lipids yield of approximately 10% was obtained at optimum conditions of 300 rpm stirring speed and 2 h duration compared to the total contents of lipids being 12%. Furthermore, an easiness of hexane recovery may be considered as economically and ecologically attractive. For the first time, in the current work catalytic hydrodeoxygenation (HDO) of Chlorella algal lipids was studied over 5 wt% Ni/H-Y-80 and 5 wt% Ni/SiO2 at 300 C and under 30 bar total pressure in H2. A comparative HDO of stearic acid was carried out under similar conditions. The conversion of lipids was about 35% over 5 wt% Ni/H-Y-80 after 6h, whereas, 5 wt% Ni/SiO2 was totally deactivated after 60 min. The selectivity to hydrocarbons (C15-C18) is 6%. As a comparison, complete conversion of stearic acid over 5 wt% Ni/H-Y-80 was achieved in 6 h. The transformation of lipids proceeded mostly via hydrogenation and hydrolysis with formation of free fatty acid (FFA). The lower activity might be attributed to deactivation of catalysts caused by chlorophylls and carotenoids. Even though the conversion is low, future studies in HDO of lipids extracted from other algae species having higher lipid content could be proposed. Coke resistant catalyst might be considered to improve catalytic activity.
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Membranes are dynamic structures that affect cell structure and function. Compositional changes ofmembranes have been shown with the application of a perturbation; however these are limited to whole tissue analysis. The purpose of this thesis was to compare the phospholipid (PL) fatty acid (FA) composition of rat whole muscle (Wm) to 1) purified and non-purified subsarcolemmal (SS) mitochondria in soleus, plantaris, and red gastrocnemius, and 2) sarcolemma, transverse-tubules, SS and intermyofibrillar (IMF) mitochondria fix)m whole hindlimb. The major findings were that 1) contamination significantly altered the PL FA composition of the SS mitochondrial membrane fraction, 2) Wm and SS mitochondria compositions differed between muscle types, and 3) Wm did not accurately reflect the PL FA composition of any isolated subcellular membranes, with each being unique from each other. As such, the relevancy of the trends reported in the literature of the effects of perturbations on Wm may be limited.
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The distribution of excitation energy between the two photosystems (PSII and PSI) of photosynthesis is regulated by the light state transition. Three models have been proposed for the mechanism of the state transition in phycobilisome (PBS) containing organisms, two involving protein phosphorylation. A procedure for the rapid isolation of thylakoid membranes and PBS fractions from the cyanobacterium Synechococcus m. PCC 6301 in light state 1 and light state 2 was developed. The phosphorylation of thylakoid and soluble proteins rapidly isolated from intact cells in state 1 and state 2 was investigated. 77 K fluorescence emission spectra revealed that rapidly isolated thylakoid membranes retained the excitation energy distribution characteristic of intact cells in state 1 and state 2. Phosphoproteins were identified by gel electrophoresis of both thylakoid membrane and phycobilisome fractions isolated from cells labelled with 32p orthophosphate. The results showed very close phosphoprotein patterns for either thylakoid membrane or PBS fractions in state 1 and state 2. These results do not support proposed models for the state transition which required phosphorylation of PBS or thylakoid membrane proteins.
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Thylakoid membrane fractions were prepared from specific regions of thylakoid membranes of spinach (Spinacia oleracea). These fractions, which include grana (83), stroma (T3), grana core (8S), margins (Ma) and purified stroma (Y100) were prepared using a non-detergent method including a mild sonication and aqueous two-phase partitioning. The significance of PSlla and PSII~ centres have been described extensively in the literature. Previous work has characterized two types of PSII centres which are proposed to exist in different regions of the thylakoid membrane. a-centres are suggested to aggregate in stacked regions of grana whereas ~-centres are located in unstacked regions of stroma lamellae. The goal of this study is to characterize photosystem II from the isolated membrane vesicles representing different regions of the higher plant thylakoid membrane. The low temperature absorption spectra have been deconvoluted via Gaussian decomposition to estimate the relative sub-components that contribute to each fractions signature absorption spectrum. The relative sizes of the functional PSII antenna and the fluorescence induction kinetics were measured and used to determine the relative contributions of PSlla and PSII~ to each fraction. Picosecond chlorophyll fluorescence decay kinetics were collected for each fraction to characterize and gain insight into excitation energy transfer and primary electron transport in PSlla and PSII~ centres. The results presented here clearly illustrate the widely held notions of PSII/PS·I and PSlIa/PSII~ spatial separation. This study suggests that chlorophyll fluorescence decay lifetimes of PSII~ centres are shorter than those of PSlIa centres and, at FM, the longer lived of the two PSII components renders a larger yield in PSlIa-rich fractions, but smaller in PSIlr3-rich fractions.