Difference in rates of net portal absorption between crystalline and protein-bound lysine and threonine in growing pigs fed once daily

Net portal absorption of AA during the 6-h postprandial period was measured in eight gilts (48.5 +/- 1.6 kg BW) in a crossover design. The pigs had chronic catheters placed in the portal vein, carotid artery, and ileal vein, and were trained to consume 1.2 kg of a standard grower diet once daily. Blood samples were taken every 30 min for 4 h and then hourly until 6 h after feeding. The first set of blood samples was taken after pigs were fed a meal of the test 16% CP corn-soybean meal diet (16% CP) or the test 12% CP corn-soybean meal diet supplemented with crystalline lysine, threonine, and tryptophan (12% CP + AA) to equal the three AA levels in the 16% CP diet. Pigs were then fed the standard diet for 2 d. Following that, blood samples were again taken after the pigs were fed a meal of the test diet that was not given to them at the first sampling period. Net portal AA absorption was calculated by multiplying porto-arterial plasma AA concentration difference by portal vein plasma flow rate (PVPF), estimated by an indicator-dilution technique employing p-aminohippuric acid as the indicator infused into the ileal vein. Plasma concentrations of lysine and threonine of pigs were affected by the diet x time interaction (P < 0.01). Portal and arterial plasma lysine and threonine concentrations in pigs attained the maximal level by 1 h postprandial when the 12% CP + AA diet was fed, but reached the peak level at 2.5 h postprandial when the 16% CP diet was given. The PVPF of pigs over the 6 h postprandial was less (P < 0.01) when the 12% CP + AA diet was given than when the 16% CP diet was fed. Net portal absorptions of lysine and threonine also were affected (P < 0.05) by time x diet interaction. The peak portal absorption of both lysine and threonine in pigs appeared at 0.5 h postprandial when the 12% CP + AA diet was given, but at 2.5 h postprandial with the feeding of the 16% CP diet. The early appearance of peak portal absorption of lysine and threonine from feeding the 12% CP + AA compared with the 16% CP diet indicates that crystalline lysine and threonine are absorbed more rapidly than protein-bound lysine and threonine in pigs fed once daily.     

Metabolic and microbial responses in western crossbred and Meishan growing pigs fed a high-fiber diet

Four Duroc x White composite crossbred (21.8 +/- 1.0 kg BW) and four 12-wk-old Meishan purebred (20.7 +/- 1.6 kg BW) growing barrows were used to determine the relative breed differences in metabolic and microbial responses to a high-fiber diet. The pigs were trained to consume 700 g of a diet containing 35% (as-fed basis) dehydrated alfalfa meal once daily. The pigs' daily intakes of DM, N, GE, NDF, and ADF were 610 g, 16.6 g, 2.64 Mcal, 150 g, and 88 g, respectively. On d 12 after surgical catheterization of the portal vein, ileal vein, and carotid artery, a 3-d total urine and feces collection was conducted. On d 24 after surgery, each pig was placed in an open-circuit calorimeter, and its catheters were connected to a system for simultaneous measurements of oxygen consumption by portal-drained viscera and by whole body, and the net portal absorption of VFA after a 24-h fasting and during a 5-h postprandial period. The VFA measured included acetic, propionic, isobutyric, butyric, isovaleric, and valeric acids. A second 3-d total urine and feces collection was conducted on d 30 after surgery. There were no differences (P = 0.13) between the first and second collections in apparent total-tract digestibility coefficients for nutrients and N retention of pigs. Compared with Duroc x White composite crossbred pigs, Meishan pigs had lower (P = 0.05) apparent digestibility coefficients for DM, N, NDF, hemicellulose, and N retention, but their portal-drained viscera used a greater (P = 0.05) fraction of whole-body oxygen consumption. No differences (P = 0.12) were found between Duroc x White composite crossbred and Meishan pigs in total viable bacteria and cellulolytic bacteria from fecal samples, in vitro digestibility of alfalfa NDF fractions by fecal inocula, whole-body oxygen consumption, net portal absorption of VFA, total energy of absorbed VFA, and the potential of absorbed VFA for meeting the energy needs for whole-body heat production. These results indicate that, in contrast to previous beliefs, the ability of Meishan growing pigs to utilize a high-fiber diet is not superior to that of Duroc x White composite crossbred growing pigs.     

Inhibitory effect of phenolic acids on the proliferation of 3T3-L1 preadipocytes in relation to their antioxidant activity

Obesity is an important topic in the world of public health and preventive medicine. Inhibition of preadipocyte proliferation plays an important role in the mechanisms of proposed antiobesity. In this in vitro study, the inhibitory effect of phenolic acids on 3T3-L1 preadipocytes was evaluated, and a relationship analysis was then conducted. The results showed that the addition of phenolic acids to the growth medium decreased the cell population growth of 3T3-L1 preadipocytes. The IC50 values of chlorogenic acid, gallic acid, o-coumaric acid and m-coumaric acid on 3T3-L1 preadipocytes were 72.3, 43.3, 48.2, and 49.2 microM, respectively. A relationship analysis indicated that there is a significant linear correlation between the influence of phenolic acids on cell population growth and their antioxidant activity (r = 0.77, p < 0.01). The cell cycle assay indicated that the treatment of 3T3-L1 preadipocytes with chlorogenic acid, o-coumaric acid, and m-coumaric acid caused cell cycle arrest in the G1 phase. Gallic acid did not affect the cell cycle profile; however, it increased the number of apoptotic cells (sub-G1 phase) in a time- and dose-dependent manner. Annexin V-fluorescein isothiocyanate (FITC)-propidium iodide (PI) apoptosis flow cytometric assay showed that gallic acid increased the number of early apoptotic (annexin V-FITC+/PI-) and late apoptotic cells (annexin V-FITC+/PI+) but not necrotic cells (annexin V-FITC-/PI+). The treatment of cells with gallic acid caused the loss of mitochondrial membrane potential (delta psi(m)). These results indicate that the inhibition of preadipocyte population growth by some phenolic acids might have further implication in in vivo antiobesity effects.     

Functional processing of PET fabrics using boehmite/silica/thiazole dye hybrid materials

A series of hybrid materials composed of boehmite/silica/thiazole dyes and prepared via the sol-gel process is synthesized from aluminum isopropoxide (AIP) and tetraethoxysilane using heteroaryl 2-amino-thiazole azo dyes. Heterocyclic 2-amino-thiazole azo dyes undergo a hydrolysis-condensation reaction with an appropriate proportion of AIP under a catalyst, at a constant ratio of vinyltriethoxysilane (VTES) and tetraethoxysilane (TEOS). The structures of these hybrid materials composed of boehmite/silica/thiazole dyes are characterized using Fourier transform infrared (FT-IR) analysis. The surface morphology of polyethylene terephthalate (PET) fabrics is evaluated using scanning electron microscopy (SEM). SEM images show uniform dyeing of the PET fabrics that confirms the reaction of the hybrid materials with the PET fabrics. The water contact angle, washing fastness, color evenness, air permeability, and warmth retention of the PET fabrics dyed with hybrid materials composed of boehmite/silica/thiazole dyes are evaluated. The evaluation results indicate improved warmth retention property and good water repellency.     

A characterization of the soils and sediments in contaminated sites and rivers using petroleum biomarker compounds

Journal of Soils and Sediments - The objective of this study is to reveal the presence of petroleum biomarkers in sediments of contaminated sites and to prove the existence of these compounds in...     

Investigation on the lipid- and cholesterol-lowering abilities of biocellulose.

The present study investigated and compared the physicochemical properties as well as the hypolipidemic and hypocholesterolemic effects between plant cellulose and biocellulose. Biocellulose had higher water-holding and cation-exchange capacities than plant cellulose ( approximately 2- and 6-fold, respectively). The results showed that the administration of plant cellulose and biocellulose to hamsters effectively ( P < 0.05) decreased the concentrations of serum triglyceride (by 13.9-55.5%), serum total cholesterol (by 17.4-27.9%), serum low-density lipoprotein cholesterol (by 41.9-47.9%), liver total lipids (by 6.4-10.3%), and liver cholesterol (by 11.8-16.3%). Feeding plant cellulose and biocellulose also enhanced the excretion of total lipids (144-182%), cholesterol (136-203%), and bile acids (259-479%) in feces. The efficacy of biocellulose in lowering serum lipids and cholesterol in hamsters was significantly higher than that of plant cellulose. These results suggested that biocellulose could be a promising low-calorie bulking ingredient for the development of novel fiber-rich functional foods of different forms such as powder, gelatinous, or shred forms.     

Lucidenic acid B induces apoptosis in human leukemia cells via a mitochondria-mediated pathway

Ganoderma lucidum is known as a medicinal mushroom used in traditional Chinese medicine. In the present study, the effect of lucidenic acids (A, B, C, and N) isolated from a new G. lucidum (YK-02) on induction of cell apoptosis and the apoptotic pathway in HL-60 cells were investigated. The results demonstrated that lucidenic acids decreased cell population growth of HL-60 cells, assessed with the MTT assay. The cell cycle assay indicated that treatment of HL-60 cells with lucidenic acid A, C, and N caused cell cycle arrest in the G 1 phase. Lucidenic acid B (LAB) did not affect the cell cycle profile; however, it increased the number of early and late apoptotic cells but not necrotic cells. Treatment of HL-60 cells with LAB caused loss of mitochondria membrane potential. Moreover, the ratio of expression levels of pro- and antiapoptotic Bcl-2 family members was changed by LAB treatment. LAB-induced apoptosis involved release of mitochondria cytochrome c and subsequently induced the activation of caspase-9 and caspase-3, which were followed by cleavage of poly(ADP-ribose) polymerase (PARP). Pretreatment with a general caspase-9 inhibitor (Z-LEHD-FMK) and caspase-3 inhibitor (Z-DEVD-FMK) prevented LAB from inhibiting cell viability in HL-60 cells. Our finding may be critical to the chemopreventive potential of lucidenic acid B.     

Oral administration recombinant porcine epidermal growth factor enhances the jejunal digestive enzyme genes expression and activity of early-weaned piglets

This study attempted to determine ingested porcine epidermal growth factor (pEGF) on the gastrointestinal tract development of early-weaned piglets. Thirty-two piglets (14-day weaned) were randomly allotted to supplemented with 0 (control), 0.5, 1.0, or 1.5 mg pEGF/kg diet. Each treatment consisted of four replicates with two pigs per pen for a 14 days experimental period. Piglets were sacrificed and gastrointestinal tract samples were collected to measure mucosa morphology, mRNA expression and activities of digestive enzymes in the gastrointestinal tract of piglets at the end of the experiment. Diets supplemented with pEGF failed to influence growth performance but tended to increase jejunal mucosa weight (p < 0.09) and protein content (p < 0.07). Piglets supplemental pEGF induced incrementally the gastric pepsin activity (p < 0.05) and stimulated jejunal alkaline phosphatase (ALP) and lactase activities accompanied with the increase of jejunal ALP and maltase mRNA expression. No effect of pEGF on the activities of all enzymes in ileum except the stimulation of ileal aminopeptide N mRNA expression. These results reveal that dietary pEGF supplementation might enhance gene expression and activities of digestive enzymes in the stomach and jejunum of piglets.     

Chromosome location of the gene for brittle rachis in the Tibetan weedrace of common wheat

The brittle rachis of the Tibetan weedrace (Triticum aestivum var. tibetanum) was found to be governed by a single dominant gene on the short arm of chromosome 3D. The new brittle rachis gene was designated Br₁. This study also discovered that the type of disarticulation is governed by many genes that may differ from brittle rachis genes. In other words, the same brittle rachis gene may exhibit various types of disarticulation in various genetic backgrounds. So, after the brittle rachis gene (barrel type) in Aegilops tauschii entered hexaploid wheat through the amphidiploid path, it might exhibit the wedge type of disarticulation.     

稻瘟病综合防治技术应用

 综防技术应用表明,遵义地区稻瘟病逐渐得到控制,叶瘟发生由1993年的7.36×10⁴hm²,下降到1996年的3.51×10⁴hm²,穗瘟发生也由当年的9.25×10⁴hm²下降到1.31×10⁴hm²,综防治理区稻谷平均667m²产量达577.82kg,比非综防区平均667m²增产81.1kg,共挽回因病虫危害造成的产量损失约7.64×10⁷t,折款1069.8856万元,产出比1:3.5,效益显著.