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1.
Asaf A. Oureshi Neville Prentice Zafeer Z. Din Warren C. Burger Charles E. Elson Milton L. Sunde 《Lipids》1984,19(4):250-257
The suppression of hepatic 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase and cholesterol 7 α-hydroxylase, previously
noted in studies of the influences of barley and the filtrate ofTrichoderma viride culture (CF) on cholesterol metabolism in sexually immature birds, is shown in sexually mature birds. Barley, CF or both
were fed in one study from the day of hatching, in another during the period of sexual maturation and, in a third study, CF
was fed to mature layers. CF suppressed HMG CoA reductase by 30–50% and cholesterol 7 α-hydroxylase by 32–45% when added to
the control diet. In birds fed barley rather than corn, the respective activities were 25–36% and 24–31% lower. These effects
were expressed in the lowering of plasma cholesterol by 11–36%. Lipogenic activity based on the assays of 4 enzymes was increased
2–3 times by the treatments and plasma triglyceride elevated by 12–86%. The start of egg production by birds fed CF preceded
the controls by 17 days. Birds fed barley trailed controls by 11–14 days. CF countered the barley-conditioned delay. Egg yolk
cholesterol concentrations were lowered by both treatments. Eggs produced by hens fed barley were lower in weight; CF increased
egg and yolk weights. Tissues from birds fed CF or barley for up to 30 weeks appeared to be normal.
Cooperative investigation between the Science and Education Administration, USDA, and the College of Agricultural and Life
Sciences, Univesity of Wisconsin-Madison. A preliminary report of this work was presented at the 67th Annual Meeting of the
Federation of American Societies for Experimental Biology, Chicago, IL, April 10–15, 1983.
Mention of a trademark or proprietary product does not constitute a guarantee or warranty of the product by the USDA and does
not imply its approval to the exclusion of other products that may also be suitable. 相似文献
2.
Pulmonary surfactant, the major surface-active component of which in the adult is dipalmitoylglycerophosphocholine, can be
obtained by lavaging lungs with physiological saline. We have previously shown that there is an increase in the amount of
phosphatidylcholine in fetal rabbit lung lavage during the latter part of gestation. We have now measured the amount of disaturated
phosphatidylcholine as well as the fatty acid composition of phosphatidylcholine in lung lavage from fetal rabbits during
the period 27 days’ gestation to full term (31 days). There was no developmental change in the amount of disaturated phosphatidylcholine
during the period examined. About 50% of the total phosphatidylcholine was disaturated which is approximately the same as
in adult rabbit lung lavage. The fatty acid composition, however, did change. There was an increase in the amount of 16∶0
from about 20% of the total fatty acids in phosphatidylcholine at 27–28 days to about 60% at full term, after birth, and in
the adults. There was a corresponding decrease in the amounts of 14∶0, 18∶0, and longer chain fatty acids, most of which were
saturated. In the lavaged lung tissue, there was a 2.6-fold increase in the percentage of phosphatidylcholine which was disaturated
during the period 27–31 days’ gestation. It had not decrease to the adult value 24 hr after birth. 相似文献
3.
Yanhua Cui Meihong Wang Yankun Zheng Kai Miao Xiaojun Qu 《International journal of molecular sciences》2021,22(24)
Lactiplantibacillus plantarum has a strong carbohydrate utilization ability. This characteristic plays an important role in its gastrointestinal tract colonization and probiotic effects. L. plantarum LP-F1 presents a high carbohydrate utilization capacity. The genome analysis of 165 L. plantarum strains indicated the species has a plenty of carbohydrate metabolism genes, presenting a strain specificity. Furthermore, two-component systems (TCSs) analysis revealed that the species has more TCSs than other lactic acid bacteria, and the distribution of TCS also shows the strain specificity. In order to clarify the sugar metabolism mechanism under different carbohydrate fermentation conditions, the expressions of 27 carbohydrate metabolism genes, catabolite control protein A (CcpA) gene ccpA, and TCSs genes were analyzed by quantitative real-time PCR technology. The correlation analysis between the expressions of regulatory genes and sugar metabolism genes showed that some regulatory genes were correlated with most of the sugar metabolism genes, suggesting that some TCSs might be involved in the regulation of sugar metabolism. 相似文献
4.
6-Methoxy-benzoxazolin-2(3H)-one (MBOA) inhibited the germination of cress (Lepidium sativum L.) seeds at concentrations greater than 0.03 mM. Inhibition was overcome by sucrose, suggesting that MBOA may inhibit sugar metabolism in cress seeds. Induction of α-amylase activity in seeds was also inhibited by MBOA at concentrations greater than 0.03 mM. Inhibition of both germination and induction of α-amylase activity increased with increasing concentrations of MBOA, and the extent of germination correlated positively with the activity of α-amylase in the seeds. MBOA added to a reaction mixture for α-amylase assay did not affect enzyme activity, indicating that MBOA does not inhibit in vitro α-amylase activity. Cress seeds germinated approximately 16 hr after incubation, and inhibition of α-amylase by MBOA occurred within 6 hr after incubation. These results suggest that MBOA may inhibit the germination of cress seeds by inhibiting the induction of α-amylase activity, because α-amylase plays a key role in the conversion of reserve carbohydrate into soluble sugars, a prerequisite for seed germination. 相似文献
5.
The behavior of the boundaries of grains of special type in the material during high-rate shear loading was studied numerically.
Two paths of evolution of the simulated system were shown: an intense rearrangement of the intergrain boundary occurs at high
deformation rates and the process of relaxation of the energy supplied to the material is accomplished by displacing the boundary
as the intensity of loading is decreased. The calculations showed that the intergrain boundary can be shifted with an abnormally
fast speed. Vortex collective motion of the atoms causes high velocities of displacement of the grain boundaries.
Translated fromFizika Goreniya i Vzryva, Vol. 34, No. 3, pp. 126–128, May–June 1998. 相似文献
6.
Maltose long-chain fatty acid esters (MFAE), esterified at the 6 and 6′ position, were synthesized with stearic, palmitic,
myristic, and oleic groups. Synthesis yields were 15–20% based on initial maltose present, and structural confirmation was
obtained using plasma desorption mass spectrometry and nuclear magnetic resonance spectroscopy. These surfactants have surface
tensions in the range of 34–36 dyn/cm at their critical micelle concentrations (CMC) of approximately 10−5–10−6 mol/L. The increased chain lengths have a marked effect, reducing CMC values for MFAE by approximately three orders of magnitude
over similar carbohydrate-based dodecyl chain sources. Within chain lengths between 14 and 18 carbons, the rate of change
in CMC is significant and decreases with increasing chain length for MFAE. The melting points of MFAE are approximately 40°C,
and the heat capacities range from 1.6 to 1.9 J/g·K. These numbers are comparable to those of sucrose esters, indicating their
applicability in similar uses. However, because MFAE, unlike sucrose, possess an anomeric carbohydrate carbon position, these
surfactants maintain their reducing nature and are susceptible to further derivatization. They are also synthesized from renewable,
economical carbohydrates and lipids and may provide an excellent alternative to pertrochemical-derived products. 相似文献
7.
O. N. Ignatova I. I. Kaganova A. N. Malyshev A. M. Podurets V. A. Raevskii V. I. Skokov M. I. Tkachenko G. A. Salishchev T. N. Kon’kova 《Combustion, Explosion, and Shock Waves》2010,46(6):719-723
It is shown that preloading of fine-grained copper with a the grain size of 0.5 m by a shock wave of intensity ≈25–50 GPa
does not lead to changes in its internal microstructure and mechanical properties, and the dislocation density increases only
slightly from 1.8 · 1011 cms-2 in the initial state to (3.1–3.6) · 1011 cms-2 after shockwave loading. An increase in shock wave intensity to pressures > 55 GPa leads to a decrease in the dislocation
density to 2.5 · 109 cms-2, an increase in the grain size to ≈19 fum, the occurrence of microtwins inside the grains, and a reduction in the mechanical
properties of fine-grained copper to the level of coarse-crystalline copper. 相似文献
8.
S. Sitthaphanit V. Limpinuntana B. Toomsan S. Panchaban R. W. Bell 《Nutrient Cycling in Agroecosystems》2009,85(2):123-139
Fertiliser application strategies for maize (Zea
mays L.) production on sandy soils under high rainfall regimes need to be carefully designed to minimise nutrient losses through
leaching and maximise crop yield. Experiments were conducted to determine N, P, and K leaching in sandy soils with 3–6% clay
in surface layers under maize production, and the effectiveness of different N, P, and K fertiliser timing and splitting strategies
on leaching of N, P, and K and on maize yield. In a column experiment on an Oxic Paleustult (Korat series) with 3% clay, leaching
of N, P, and K from fertiliser (114N-17P-22K in kg ha−1) was significant under simulated rainfall, but decreased to negligible levels with 3–5 split applications of fertiliser.
Maize N and K uptake increased with 3–5 split applications, but not P uptake. Despite continued intense rainfall and further
fertilizer additions, leaching was not recorded after day 30, and this was attributed to the effect of plant water uptake
on reducing deep drainage. Split applications of fertilizer maintained NP and K in the 0–30 cm layer during 30–60 days when
maize nutrient demand was likely to be at its highest, while in the recommended fertilizer regime NPK in the surface layers
declined after 30 days. In a field experiment on an Oxic Paleustult (Korat series) with 6% clay, 3–4 splits of fertiliser
increased N and K uptake and increased maize yields from 3.3 to 4.5 Mg ha−1. Postponing basal fertiliser application from pre-planting to 7–15 days after emergence increased uptake of N, P, and K and
grain yield emphasising the greater risk of nutrient losses from fertiliser applied at planting than later. Strategies designed
to reduce the amount of nutrients applied as fertiliser at planting, such as split application and postponing basal application
can decrease the risk of leaching of N, P, and K from fertiliser and improve nutrient use efficiency, and grain yield of maize
on sandy soils under high growing season rainfall regimes. 相似文献
9.
Ana C. Lo Prete Clederson H. Dina Carolina H. Azevedo Camila G. Puk Neuza H. M. Lopes Whady A. Hueb Raul Cavalcante Maranhão 《Lipids》2009,44(10):917-924
The exchange of lipids with cells and other lipoproteins is a crucial process in HDL metabolism and for HDL antiatherogenic
function. Here, we tested a practical method to quantify the simultaneous transfer to HDL of phospholipids, free-cholesterol,
esterified cholesterol and triacylglycerols and to verify the lipid transfer in patients with coronary artery disease (CAD)
or undergoing statin treatment. Twenty-eight control subjects without CAD, 27 with CAD and 25 CAD patients under simvastatin
treatment were studied. Plasma samples were incubated with a donor nanoemulsion prepared by ultrasonication of the constituent
lipids and labeled with radioactive lipids; % lipids transferred to HDL were quantified in the HDL-containing supernatant
after chemical precipitation of non-HDL fractions and the nanoemulsion. The assay was precise and reproducible. Increase of
temperature (4–37 °C), of incubation period (5 min to 2 h), of HDL-cholesterol concentration (33–244 mg/dL) and of mass of
nanoemulsion lipids (0.075–0.3 mg/μL) resulted in increased lipid transfer from the nanoemulsion to HDL. In contrast, increasing
pH (6.5–8.5) and albumin concentration (3.5–7.0 g/dL) did not affect lipid transfer. There was no difference between CAD and
control non-CAD with regard to the lipid transfer, but statin treatment reduced the transfer to HDL of all four lipids. The
test herein described is a valid and practical tool for exploring an important aspect of HDL metabolism. 相似文献
10.
Substantial research suggests that the t10,c12–18:2, but not the c9,t11–18:2, isomer of conjugated linoleic acid (CLA) reduces milk fat synthesis in lactating bovine and rodent species. Because
fat is the major energy-yielding component in human milk, we were interested in whether this is true for women as well. Thus,
the effects of c9,t11–18:2 and t10,c12–18:2 on milk fat were examined in breast-feeding women (n = 12) in a double-blind, placebo-controlled, crossover study with latin-square design. The study was divided into six periods:
baseline (3 days), three intervention periods (5 days each), and two washout periods (9 days each). During each intervention
period, women consumed 750 mg/day of a supplement containing predominantly c9,t11–18:2, t10,c12–18:2, or 18:1 (olive oil placebo). Milk was collected by complete breast expression on the final day of each period. Infant
milk consumption was estimated by 24 h weighing on the penultimate day of each intervention and washout period, and maternal
adiposity (% body fat) was determined at baseline using dual energy X-ray absorptiometry. Milk c9,t11–18:2 and t10,c12–18:2 concentrations were greater (P < 0.05) during the corresponding CLA treatment periods as compared to the placebo period, providing strong evidence of subject
compliance. Both CLA isomers were transferred into milk fat at relatively high efficiency; average transfer efficiency was
estimated to be 23.3%. Compared to the placebo treatment, milk fat content was not reduced during either CLA treatment. Data
indicate that body fatness did not modify any putative effect of isomeric CLA consumption on milk fat concentration. The evidence
from this study suggests that the sensitivity of lactating women’s mammary tissue to an anti-lipogenic effect of the t10,c12–18:2 isoform of CLA may be less than previously hypothesized. 相似文献
11.
Female rats warm-adapted at 30–32 C for 20–25 days and then shifted to 13–15 C for 12, 24, 48, 72 and 120 hr showed that Δ9
desaturase and fatty acid synthetase activity decay after 24 hr of cold exposure, while Δ6 and Δ5 desaturases were increased
after this period of time. These results were confirmed by an increase of arachidonic acid of heart and liver microsomes phosphatidylcholine
and a decrease of oleic acid. Neither NADH-cyt b5 reductase nor NADH-cyt c reductase activity of liver microsomes were significantly affected. Male rats warm-adapted under
the same conditions and then shifted to 13–15 C for 120 hr did not show significant changes in fatty acid synthetase, Δ9 and
Δ6 desaturases and enzymes of the microsomal electron transport chain. Therefore, the desaturase response to environmental
temperature changes could be plausibly linked to female hormones. 相似文献
12.
A sucrose-rich diet (SRD) induces insulin resistance and dyslipidemia with impaired hepatic glucose production and gluconeogenesis,
accompanied by altered post-receptor insulin signaling steps. The aim of this study was to examine the effectiveness of fish
oil (FO) to reverse or improve the impaired hepatic glucose metabolism once installed in rats fed 8 months a SRD. In the liver
of rats fed SRD in which FO replaced corn-oil during the last 2 months, as dietary fat, several key enzyme activities and
metabolites involved in glucose metabolisms (phosphorylation, glycolysis, gluconeogenesis and oxidative and non oxidative
glucose pathway) were measured. The protein mass levels of IRS-1 and αp85 PI-3K at basal conditions were also analyzed. FO
improved the altered activities of some enzymes involved in the glycolytic and oxidative pathways observed in the liver of
SRD fed rats but was unable to restore the impaired capacity of glucose phosphorylation. Moreover, FO reversed the increase
in PEPCK and G-6-Pase and reduced the G-6-Pase/GK ratio. Glycogen concentration and GSa activity returned to levels similar
to those observed in the liver of the control-fed rats. Besides, FO did not modify the altered protein mass levels of IRS-1
and αp85 PI-3K. Finally, dietary FO was effective in reversing or improving the impaired activities of several key enzymes
of hepatic carbohydrate metabolism contributing, at least in part, to the normalization of plasma glucose levels in the SRD-fed
rats. However, these positive effects of FO were not observed under basal conditions in the early steps of insulin signaling
transduction. 相似文献
13.
Jeff S. Volek Stephen D. Phinney Cassandra E. Forsythe Erin E. Quann Richard J. Wood Michael J. Puglisi William J. Kraemer Doug M. Bibus Maria Luz Fernandez Richard D. Feinman 《Lipids》2009,44(4):297-309
We recently proposed that the biological markers improved by carbohydrate restriction were precisely those that define the
metabolic syndrome (MetS), and that the common thread was regulation of insulin as a control element. We specifically tested
the idea with a 12-week study comparing two hypocaloric diets (~1,500 kcal): a carbohydrate-restricted diet (CRD) (%carbohydrate:fat:protein = 12:59:28)
and a low-fat diet (LFD) (56:24:20) in 40 subjects with atherogenic dyslipidemia. Both interventions led to improvements in
several metabolic markers, but subjects following the CRD had consistently reduced glucose (−12%) and insulin (−50%) concentrations,
insulin sensitivity (−55%), weight loss (−10%), decreased adiposity (−14%), and more favorable triacylglycerol (TAG) (−51%),
HDL-C (13%) and total cholesterol/HDL-C ratio (−14%) responses. In addition to these markers for MetS, the CRD subjects showed
more favorable responses to alternative indicators of cardiovascular risk: postprandial lipemia (−47%), the Apo B/Apo A-1
ratio (−16%), and LDL particle distribution. Despite a threefold higher intake of dietary saturated fat during the CRD, saturated
fatty acids in TAG and cholesteryl ester were significantly decreased, as was palmitoleic acid (16:1n-7), an endogenous marker
of lipogenesis, compared to subjects consuming the LFD. Serum retinol binding protein 4 has been linked to insulin-resistant
states, and only the CRD decreased this marker (−20%). The findings provide support for unifying the disparate markers of
MetS and for the proposed intimate connection with dietary carbohydrate. The results support the use of dietary carbohydrate
restriction as an effective approach to improve features of MetS and cardiovascular risk.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
14.
Fatty Acid Composition of the Oil from Developing Seeds of Different Varieties of Safflower (Carthamus tinctorius L.) 总被引:2,自引:0,他引:2
Umit Gecgel Mehmet Demirci Enver Esendal Murat Tasan 《Journal of the American Oil Chemists' Society》2007,84(1):47-54
Fatty acid composition and moisture and oil content were determined for Montola-2001 and Centennial safflower varieties at
three different harvest dates from flowering to maturity, which were grown as autumn and spring crops in two different locations
in 2001–2002 and 2002–2003. The experiment was carried out using split–split plots in a randomized complete block design with
three replicates. Sowing dates affected oil content and fatty acid compositions significantly (P < 0.01), whereas moisture content in both years was not significantly affected. Moisture content declined 15 days from flowering
period to maturity, while oil content increased. The rate of the palmitic acid formation decreased in both varieties 15 days
from flowering period to maturity, whereas formation rates of the oleic and linoleic acids increased in Montola-2001 and Centennial
varieties, respectively. 相似文献
15.
We presents the results of damage of a carbon steel plate30 mm thick upon its loading by the impact of a steel ball5.55 mm in diameter at a velocity of up to7.4 km/sec. The dimensions of the crater formed and the bending flexure of the spalling layer are in good agreement with the results
obtained upon a less intense loading of the target. One more feature of damage, namely, a crack passing through the target
at the level of the crater bottom, has been revealed for the first time.
Institute of Experimental Physics, Sarov 607200. Translated from Fizika Goreniya i Vzryva, Vol. 33, No. 1, pp. 119–121, January–February,
1997. 相似文献
16.
Pregnant rats were fed a high carbohydrate diet containing either 1% trilinolein or 1% trilinolein with 0.2% methyl sterculate
from 18 day gestation to 21 day postpartum. The pups were weaned at 21 days and continued on the same diet for an additional
10 days. The microsomal stearyl CoA desaturase activities of the liver were effectively inhibited. Liver triglycerides showed
increases in the saturated fatty acids concentrations at the expense of the corresponding monoenes. The concentration ofcis 6–7 octadecenoic acid was elevated. In liver phospholipids, the concentration of stearic acid was increased without a corresponding
decrease in the oleic acid content. A drastic decrease in the nervonic acid (24∶1, n−9) concentration of liver sphingomyelin
was observed. The lipids of the brain did not contain sterculic acid, and brain desaturase activity was unaffected. There
was no significant change in the concentration of monoenoic acids from 16∶1 to 22∶1. However, nervonic acid was decreased
by 32%. These results suggest that brain nervonic acid may be derived from a precursor other than oleic acid. 相似文献
17.
18.
Maria Luz Fernandez A. Karin Conde Laura R. Ruiz Carlos Montano John Ebner Donald J. McNamara 《Lipids》1995,30(7):619-626
To test the effects of exchanging dietary complex and simple carbohydrate for fat calories on lipoprotein metabolism, guinea
pigs were fed two different fat/carbohydrate ratios: 2.5∶58% (w/w) or 25∶29% (w/w) with either sucrose or starch as the carbohydrate
source. Animals fed high-fat had higher plasma low-density lipoprotein (LDL) and hepatic cholesterol concentrations than animals
fed low-fat diets (P<0.01). The cholesteryl ester content per particle was higher, and the number of triacylglycerol (TAG) molecules was lower
in very low density lipoprotein (VLDL) and LDL from animals fed high-fat diets. Intake of high-fat/sucrose resulted in higher
plasma LDL concentrations than intake of high-fat/starch, and animals fed low-fat/starch had the highest plasma TAG concentrations
associated with VLDL particles containing more TAG molecules, as well as a TAG-enriched LDL. The activity of plasma lecithin
cholesteryl:acyl transferase (LCAT) was highest in animals fed high-fat/sucrose, and heart lipoprotein lipase (LPL) activity
was higher in animals fed high-fat diets. Hepatic apoprotein B/E (apo B/E) receptor number (Bmax) was increased 21% with low-fat diets (P<0.01). These results suggest that the hypercholesterolemia induced by high-fat and by sucrose intake are associated with
a higher plasma LCAT activity which results in a cholesteryl ester-enriched VLDL which, by the action of LPL, might be more
readily converted to LDL through the delipidation cascade leading to downregulation of hepatic apo B/E receptors. The hypertriglyceridemia
associated with low-fat intake may result from increased production of VLDL TAG, which would explain the increased TAG content
and the higher TAG/CE ratio of VLDL from animals fed the low-fat/starch diet. 相似文献
19.
Ming Wang Shao Sheng Wang Lei Lu Xiu Hua Wang Yi Tai Qian 《Journal of Porous Materials》2009,16(3):247-250
Partially carbonized microtubes with inner and outer diameters of 1–1.25 μm and 2–2.5 μm, respectively, and length up to 2–3 cm,
were prepared at a liquid interface at room temperature using paraformaldehyde as the carbon source. The microtubes were mesoporous
and had intense photoluminescence over the whole visible spectrum at room temperature. Their composition was determined using
an elemental analyzer and morphology was studied with scanning and transmission electron microscopes. A possible formation
mechanism was also proposed. 相似文献