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The Effects of Maternal Folic Acid Supplementation Provided in Utero and during Lactation on Genomic DNA Methylation and Global Gene Expression in the OffspringCrowell, Julie Anne 04 September 2012 (has links)
The effects of high maternal folate status on the offspring are unknown; however, early life exposure to environmental stimuli, including dietary factors, is thought to influence the risk of developing chronic disease. An animal study was performed to determine the effect of maternal folic acid supplementation during pregnancy and lactation on DNA methylation and global gene expression patterns in the offspring. Supplementation of the maternal diet with folic acid (5, 8, and 25 mg/kg diet) induced global DNA hypomethylation in the liver of juvenile and adult offspring, and altered the expression of the imprinted H19 gene and genes involved in lipid metabolism, coagulation, and iron transport and homeostasis. Our data suggest that intrauterine and early postnatal periods are susceptible to changes in DNA methylation and gene expression in response to high levels of folic acid, which may be associated with health status and disease later in life.
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Arginine and Conjugated Linoleic Acid Reduce Fat Mass in RatsNall, Jennifer L. 2008 May 1900 (has links)
We hypothesized that subcutaneous (s.c.) adipose tissue would differ in
monounsaturated (MUFA) and saturated fatty acid (SFA) composition among different depots throughout a beef carcass. To test this, 50 carcasses from a variety of breed types
and backgrounds were sampled. External fat samples were collected from eight different
carcass locations: round, sirloin, loin, rib, chuck, brisket, plate and flank. Samples were
used to provide information on slip points, fatty acid composition and MUFA:SFA
ratios. Lipids were extracted from s.c. adipose tissue by a modified chloroform:methanol procedure, and fatty acid composition and slip points were measured. The brisket was significantly lower in palmitic (16:0) and stearic (18:0) acid than the other seven sampling sites (P = 0.001). The brisket demonstrated the highest values of MUFA (P = 0.001) with the exception of possessing the lowest value of transvaccenic (18:1t11) acid (P = 0.002). There were also significant differences in the amounts of PUFA among the eight sampling sites. The lowest values were from the brisket with a mean of 25.1. The flank had the highest slip point with a mean of 39.0
(P ≤ 0.001). There was a high negative correlation shown between palmitoleic and
stearic acid (R2 = 0.827). The brisket displayed the highest values for MUFA:SFA ratios (P = 0.001), whereas the flank was the lowest. Due to the significant differences
amongst fat depots within bovine carcasses in their fatty acid composition we conclude
that substantial differences exist across fat depots.
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Comparison of the effects of docosahexaenoic acid and palmitic acid on ischemia reperfusion injury using an isolated perfused rat heart.Smith, Tracy January 2012 (has links)
Dietary docosahexaenoic acid (22:6n-3, DHA) has been shown to exert beneficial effects on coronary heart disease including the prevention of ischemia reperfusion injury. The ability to acutely infuse DHA to the heart to prevent ischemia reperfusion injury is a potentialy valuable tool in planned surgery where reperfusion and/or ischemia will take place including coronary artery bypass surgery and angioplasty. In the present study, hearts from chow-fed (AIN-93M) Sprague Dawley rats (male) 9-12 weeks of age were isolated and artificially perfused. The protocol included: 30 min stabilization period, 30 min global no flow ischemia, 15 min fatty acid infusion with reperfusion, and 75 min reperfusion in the absence of fatty acids. The fatty acid infusions included 10, 20, 40, 60, 80, 100 or 120 µM of either palmitate or DHA complexed to 3% essentially fatty acid free bovine serum albumin as well as a vehicle control. Heart functional data was recorded continuously and total heart infarct volume was determined after staining with triphenyltetrazolium chloride. DHA at 10µM significantly reduced the infarction area at the end of the reperfusion period compared to that observed in the10µM of palmitate and vehicle control conditions. Infarction areas after infusions with DHA or palmitate were similar to controls after 20-60 µM infusions and greater than controls after 80-120 µM infusions, except for the 100 µM palmitate conditions which were similar to the low and high doses. In this model of infusion, 120 µM of fatty acid was the maximum amount of DHA tolerated, as several hearts went into fibrillation and did not recover and failed to complete the reperfusion at concentrations greater than 120 µM of DHA. DHA and palmitate also exerted dose dependent effects on functional parameters. In summary, infusion of DHA and palmitate cause dose dependent effects on heart function.
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An investigation of spruce thioligninAhlm, C. Edward (Carl Edward) 01 January 1940 (has links)
No description available.
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Effects of dietary arachidonic acid on growth performance and immune responses of juvenile grouper, Epinephelus coioidesWu, Shih-Ting 07 September 2011 (has links)
This research studied the dietary effect of arachidonic acid (ARA) on growth performance and immune responses in juvenile grouper (Epinephelus coioides). The test diets used casein as protein source, and contained 9 g/100g lipid. Cod liver oil and arachidonic acid oil were used to adjust the ARA levels to 0, 0.2, 0.4, 0.6, 0.6, 0.8, and 1.0 g/100 g diet in the 5 test diets, respectively. Result of 12-week feeding trial show that the ARA supplementation had no significantly effect on the weight gain of the grouper, although 0.6 % and 0.8% groups showed higher weight gains than other groups. Liver fatty acid composition of the groupers was affected by dietary ARA. Liver ARA concentration, ARA/EPA and ARA/DHA increased with increasing dietary ARA levels. The immune responses was affected significantly by the dietary treatments. Dietary supplementation of ARA significantly enhanced plasma lysozyme activity. Lysozyme activity was increased with increasing dietary ARA levels. Dietary ARA significantly also enhanced head-kidney leucocytes respiratory burst activity. The respiratory burst activity of the 0.6 % ARA group was significantly higher than the other groups. Dietary ARA significantly enhanced head-kidney leucocyte proliferation and the dosages of 0.6 % and 0.8 % ARA were significantly more effective than the other groups. The blood phagocytic activity of the 0.6 % ARA was significantly higher than the other groups. The blood cytokine IL-1£] and TNF-£\ was significantly higher in the 0.8 % ARA group than the other groups. This research shows that feeding the grouper diets cointaining ARA at an optimal level could significantly increase immune responses of the fish.
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Experimental Study of Filter Cake Cleanup by Acid/Water JettingZhang, Yanbin 16 January 2010 (has links)
The main purpose of acid/water jetting treatments currently applied in the field is
to clean up the filter cake formed during the drilling process and perhaps further
stimulate the wellbore by creating wormholes if acid jetting is used in carbonate
formation. This purpose can be achieved for the reason that the filter cake on the
borehole can be mechanically broken by the high speed jetting action, and additionally,
if acid is used, some materials in the filter cake can be dissolved, which can facilitate the
mechanical breaking action. The knowledge of jetting effectiveness under various
conditions is crucial for the purpose of optimizing the treatment design.
In order to investigate quantitatively the effectiveness of acid/water jetting for
filter cake cleanup and wellbore productivity enhancement, laboratory experiments were
carried out under conditions similar to those in the field. Filter cake was deposited on the
face of a 4 inch diameter core and then water or 15% HCl were used for jetting
treatment. The original permeability, the permeability right after the drill-in fluid
damage, and the permeability after the jetting treatment were measured and compared.
The effect of overbalance pressure during the jetting treatment was investigated. CT scan
was carried out for those cores that may have wormholes after the acid jetting treatment.
An analysis of the mechanism for filter cake removal and wormhole creating during acid
jetting treatment was proposed.
It is discovered that acid jetting can effectively remove the filter cake by
penetrating and lifting it from beneath, and efficient wormhole creation can only happen
when the overbalance pressure during the acid jetting treatment is above a certain value.
Based on this study, several suggestions for field applications were made.
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Laboratory-scale fracture conductivity created by acid etchingPournik, Maysam 15 May 2009 (has links)
Success of acid fracturing treatment depends greatly on the created conductivity
under closure stress. In order to have sufficient conductivity, the fracture face must be
non-uniformly etched while the fracture strength maintained to withstand the closure
stress. While there have been several experimental studies conducted on acid fracturing,
most of these have not scaled experiments to field conditions and did not account for the
effect of rock weakening and etching pattern. Hence, acid fracture conductivity
predictions based on the above works have not been able to match actual results.
In order to develop a more appropriate and accurate prediction of acid fracturing
treatment outcome, a laboratory facility was developed that is properly scaled to field
conditions and enables analysis of etching pattern and rock strength. A systematic
experimental study that covered a variety of formations, acid types, and acid contact
times was conducted. An acid fracture conductivity correlation was developed based on
etched volume, etched pattern, and fracture strength under closure stress.
Results suggested that there is an optimal time of acid exposure resulting in
maximum fracture conductivity. There were large differences in the conductivity created with the different acid systems tested due to different etching patterns and degree of rock
strength weakening. There was an optimal acid system depending on formation type,
contact time and overburden stress. The acid fracture conductivities measured did not
agree with the predictions of the Nierode-Kruk correlation. The newly developed
correlation predicts conductivity much closer as it includes the effect of rock strength
and surface etching pattern on resulting conductivity.
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Docosahexaenoic acid and butyrate synergistically modulate intracellular calcium compartmentalization to induce colonocyte apoptosisKolar, Satya Sree N. 15 May 2009 (has links)
Docosahexaenoic acid (DHA, 22:6n-3) from fish oil, and butyrate, a short-chain
fatty acid fiber-fermentation product, protect against colon tumorigenesis in part by
coordinately inducing apoptosis. We have demonstrated that the combination of these
two bioactive compounds demonstrates an enhanced ability to induce colonocyte
apoptosis by potentiating mitochondrial lipid oxidation. In order to explore the potential
involvement of intracellular Ca2+ in the pro-apoptotic effect of DHA and butyrate, young
adult mouse colonocytes (YAMC) and human colonocytes (HCT-116: p53+/+ and p53-
/-) were treated with DHA or linoleic acid (LA) for 72 h ± butyrate for the final 6, 12 or
24 h. Cytosolic and mitochondrial Ca2+ levels were measured using Fluo-4 and Rhod-2.
In addition, IP3 pool, store-operated channel (SOC)-mediated changes and apoptosis
were measured. DHA did not alter basal Ca2+ or apoptosis following 6 h butyrate cotreatment.
In contrast, at 12 and 24 h, DHA and butyrate treated cultures exhibited a
decrease in cytosolic Ca2+ and enhanced apoptosis compared to LA and butyrate. DHA
and butyrate also increased the mitochondrial-to-cytosolic Ca2+ ratio at 6, 12 and 24 h. The accumulation of mitochondrial Ca2+ preceded the onset of apoptosis which increased
only following 12 h of butyrate co-treatment. RU-360, a mitochondrial uniporter
inhibitor, abrogated mitochondrial Ca2+ accumulation and also partially blocked
apoptosis in DHA and butyrate co-treated cells. p53+/+ and p53-/- cells demonstrated
similar data with respect to all parameters.
Additionally, mitochondrial Ca2+ measurements were also made in rat primarycolonocyte-
culture. Rats were fed semipurified diets containing either fish oil (a source
of DHA) or corn oil (a source of LA), and colonic crypts were incubated in butyrate exvivo
and mitochondrial Ca2+ was quantified. Crypts from rats fed fish oil incubated in
butyrate exhibited an increase in the mitochondrial-to-cytosolic Ca2+ ratio compared to
fish oil only.
In summary, our results indicate for the first time that the combination of DHA
and butyrate, compared to butyrate alone, further enhances apoptosis by additionally
recruiting a p53-independent Ca2+-mediated intrinsic mitochondrial pathway. These data
explain in part why fermentable fiber when combined with fish oil exhibits an enhanced
ability to induce apoptosis and protect against colon tumorigenesis.
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The effects of acid contact time and rock surfaces on acid fracture conductivityMelendez Castillo, Maria Georgina 02 June 2009 (has links)
The conductivity created in acid fracturing is a competition between two phenomena: etching of the rock surface and weakening of the rock. This study presents experimental results of acid fracturing conductivity experiments with polymer gelled acid, while varying contact time and rock type. The experiments were conducted in a laboratory facility properly scaled from field to laboratory conditions to account for the hydrodynamic effects that take place in the field. The rocks of study were Indiana limestone, San Andres dolomite and Texas Cream chalk. Our results illustrate that acid fracturing conductivity is governed by the etching pattern of the rock surface and influenced by the hardness of the rock. If channels are created, the fracture is more likely to retain conductivity after closure. The hardness of the rock is the dominating factor to determine the conductivity response when no channeling is present. Among the rocks tested, Texas Cream chalk had the lowest hardness measurement before and after acidizing and the fracture closed at a much lower stress compared with limestone and dolomite. Dolomite had the highest conductivity under all closure stresses even without a channeling pattern. Additionally, it was observed that a higher reduction in rock strength at the contact points for dolomite yielded lower conductivity after closure. The effects of hardness variation on conductivity are higher in dolomite than in limestone and chalk. It is apparent that longer contact times do not always provide higher conductivity after closure.
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Neutral and Cationic Main Group Lewis Acids - Synthesis, Anion Complexation and Redox PropertiesDorsey, Christopher L. 2009 May 1900 (has links)
The primary goal of this research concerns the synthesis and characterization of hybrid
main group Lewis acids. Initially, the focus of this work was on the synthesis of
derivatives possessing unusual bonding interactions enforced by a rigid 1,8-
naphthalenediyl scaffold. After discovering a route to a new dilithio reagent, silicon
based derivatives featuring R3Si-F->CR3
+ and R3C-H->SiFR3 interactions of 2.703(2)
and 2.32(2) Angstrom respectively were successfully synthesized and fully characterized.
Another hybrid Lewis acid based on the 1,8-naphthalenediyl scaffold that was studied
was a trinuclear B2/Hg Lewis acid. This molecule has been shown to bind two fluoride
anions sequentially, and the binding events can be followed by differential pulsed
votammetry.
The final part of this work concerns the reactivity and redox behavior of main group
systems. It has been shown that the p-phenylene linker in 4-dimesitylboryl-1-
diarylmethylium benzenes effectively reduces electrochemical communication between
the carbocation and borane moieties when compared to systems without the linker.
Reduction of these species produces a derivative whose EPR signal is only slightly
influenced by the ^11 B center. These findings have been further substantiated by
theoretical calculations. Finally, the redox properties of alpha-phosphonio- and alpha- phosphonyl-carbocations have been studied. Chemical reduction of both species leads to
a predominately carbon centered radical with coupling to the ^31P center of 18 and 19.7 G
respectively. The alpha-phosphonio carbocations, however, also undergo ligand exchange
reactions with pyridine derivatives suggesting that these species can also be referred to as
ligand stabilized carbodications.
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