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981.
To find differentially expressed protein spots using two-dimensional electrophoresis proteomic analysis, we took blood serum samples from 40 purebred Yorkshire pigs at 12, 18, 24, and 30 weeks. Each growth stage contained 10 male pigs having half-sib pedigrees. With the pooled serum samples, two interesting spots, differentially expressed in the growth stages, were identified using MALDI-TOF-TOF MS/MS analysis as haptoglobin alpha 1S (Hp) and apolipoprotein A-IV (APOA4) gene products. The Hp was down-regulated from 12 to 30 weeks, and APOA4 was not expressed much before 18 weeks but was highly expressed in the late growth stages. There may be an inverse relationship between the Hp and APOA4 genes. Four segments for the Hp and APOA4 genes were successfully amplified with sizes around 500 bp. The porcine Hp and APOA4 genes were screened in the 40 purebred Yorkshire pigs and a random cross population (90 pigs), resulting in the location of 6 single nucleotide polymorphisms (SNPs) in the coding regions. The mutations resulted in amino acid changes in segments of Hp627, Hp742, and APOA41203. Further investigation of the function of the Hp and APOA4 genes with SNPs will be necessary to understand fully the different expression profiles and association studies. 相似文献
982.
Lee SY Lee MS Lee HY Kim SD Shim JW Jo SH Lee JW Kim JY Choi YW Baek SH Ryu SH Bae YS 《FEBS letters》2008,582(2):273-278
F2L, a peptide derived from heme-binding protein, was originally identified as an endogenous ligand for formyl peptide receptor-like (FPRL)2. Previously, we reported that F2L inhibits FPR and FPRL1-mediated signaling in neutrophils. Since endothelial cells express functional FPRL1, we examined the effect of F2L on LL-37 (an FPRL1 agonist)-induced signaling in human umbilical vein endothelial cells (HUVECs). F2L stimulated the chemotactic migration in HUVECs. However, F2L inhibited FPRL1 activity, resulting in the inhibition of cell proliferation and tube formation induced by LL-37 in HUVECs. We suggest that F2L will potentially be useful in the study of FPRL1 signaling and the development of drugs to treat diseases involving the FPRL1 in the vascular system. 相似文献
983.
Chan Sun Park Kyung Yang Park Jae Min Baek Eun Kyoung Hwang 《Journal of applied phycology》2008,20(5):485-490
Infection rates of pinhole disease in farmed Undaria pinnatifida (Harvey) Suringar were examined between November 2002 and April 2003 at an Undaria farm at Wando on the southwestern coast of Korea. The growth stages of U. pinnatifida can be defined as: a growth phase from December to the end of February, and a decay phase from March to April. There was
a significant increase in the level of infection with pinhole disease (measured as the number of pinholes per cm2) between December and April (P < 0.01). Infection progressed from the upper part of the frond in December to the basal part in April. The infection rate
of pinhole disease in relation to growth phase on farms over time is limited by the harvest of the seaweed crop at the end
of the cultivation period in April. The midrib, sporophyll and stipe showed no signs of infection at any time during the cultivation
period. The reduced physiological activity and tissue aging that occurred over time in the sporophytic life phase is the probable
cause of the increasing infection rate of the disease. 相似文献
984.
Jun JH Lee SH Kwak HB Lee ZH Seo SB Woo KM Ryoo HM Kim GS Baek JH 《Journal of cellular biochemistry》2008,103(4):1246-1255
Estrogen deficiency causes osteoporosis via increased generation of reactive oxygen species (ROS), and thus, antioxidants may prove to be the effective therapeutic candidates. We examined the effects of the antioxidant N-acetylcysteine (NAC) on osteoblastic differentiation in mouse calvarial cells. NAC (10-30 mM) enhanced alkaline phosphatase activity, mRNA expression of osteoblast differentiation-associated genes and mineralized nodule formation. It also increased expression of bone morphogenetic proteins-2, -4, and -7. The osteogenic activity of NAC was partially reduced by inhibition of glutathione synthesis. Since caffeic acid phenethyl ester did not stimulate osteoblast differentiation, it is unlikely that ROS scavenging activity of NAC is sufficient for osteogenic activity. We observed that NAC suppressed small GTPase RhoA activity and activation of RhoA by Pasteurella multocida toxin suppressed the osteogenic activity of NAC. These results suggest that NAC might exert its osteogenic activity via increased glutathione synthesis and inhibition of RhoA activation. 相似文献
985.
986.
Sang Woo Baek Jun Seok Kim Yoon Kook Park Young Soo Kim Kyeong Keun Oh 《Biotechnology and Bioprocess Engineering》2008,13(3):332-341
A batch reactor was used to investigate the dilute acid hydrolysis reaction of alpha-cellulose and sugar decomposition reactions.
Varying the sulfuric acid concentration from 0.07 to 5.0% for reaction temperatures between 180 and 220°C significantly affected
glucose yields, which ranged from about 70% to below 10%. Increasing the reaction temperature enhanced this effect. Similar
experimental results were obtained for the decomposition of xylose. For sugar decomposition reactions, less than 0.3 g/L of
furfural and 5-hydroxymethylfurfural (5-HMF) were produced from glucose and xylose in the absence of sulfuric acid at 190°C
and 15 min of reaction time, but adding a small amount of sulfuric acid (0.5%) dramatically increased the decomposition rate
and led to the formation of four undesireable products: formic acid, 5-HMF, acetic acid, and furfural. In both hydrolysis
and fermentation reactions formic acid, acetic acid, and 5-HMF severely inhibited ethanol fermentation, while furfural had
less of an inhibition effect. 相似文献
987.
Mervyn J Merrilees Pamela ST Ching Brent Beaumont Aleksander Hinek Thomas N Wight Peter N Black 《Respiratory research》2008,9(1):41
Background
COPD is characterised by loss of alveolar elastic fibers and by lack of effective repair. Elastic fibers are assembled at cell surfaces by elastin binding protein (EBP), a molecular chaperone whose function can be reversibility inhibited by chondroitin sulphate of matrix proteoglycans such as versican. This study aimed to determine if alveoli of patients with mild to moderate COPD contained increased amounts of versican and a corresponding decrease in EBP, and if these changes were correlated with decreases in elastin and FEV1.Methods
Lung samples were obtained from 26 control (FEV1 ≥ 80% predicted, FEV1/VC >0.7) and 17 COPD patients (FEV1 ≥ 40% – <80% predicted, FEV1/VC ≤ 0.7) who had undergone a lobectomy for bronchial carcinoma. Samples were processed for histological and immuno-staining. Volume fractions (Vv) of elastin in alveolar walls and alveolar rims were determined by point counting, and versican and EBP assessed by grading of staining intensities.Results
Elastin Vv was positively correlated with FEV1 for both the alveolar walls (r = 0.66, p < 0.001) and rims (r = 0.41, p < 0.01). Versican was negatively correlated with FEV1 in both regions (r = 0.30 and 0.32 respectively, p < 0.05), with the highest staining intensities found in patients with the lowest values for FEV1. Conversely, staining intensities for EBP in alveolar walls and rims and were positively correlated with FEV1 (r = 0.43 and 0.46, p < 0.01).Conclusion
Patients with mild to moderate COPD show progressively increased immuno-staining for versican and correspondingly decreased immuno-staining for EBP, with decreasing values of FEV1. These findings may explain the lack of repair of elastic fibers in the lungs of patients with moderate COPD. Removal of versican may offer a strategy for effective repair. 相似文献988.
989.
990.
Vincent P. Klink Margaret H. MacDonald Veronica E. Martins Soo-Chul Park Kyung-Hwan Kim So-Hyeon Baek Benjamin F. Matthews 《Plant Cell, Tissue and Organ Culture》2008,92(2):183-195
We developed Glycine max cv MiniMax (PI643148) that has a rapid life cycle, short stature and characteristic simple sequence repeat (SSR) markers
that could make it useful for mutant screening, functional genomics, genetic mapping and other studies involving soybeans.
We demonstrate that MiniMax is able to make somatic embryos (SEs) that rapidly develop into plantlets. Thus, the rapid cycling
habit carries over into aspects of plant regeneration. Chimaeras (having transformed roots with untransformed aerial stocks)
have been produced rapidly under non-axenic conditions using Agrobacterium rhizogenes-mediated transformation. Part of these experiments involved the engineering an enhanced green fluorescent protein (eGFP)
reporter cassette outside the multi-cloning site of a plant expression vector, permitting non-invasive visual screening of
the transformed roots. The rapid cycling growth habit of MiniMax, its ability to efficiently generate SEs and ability to be
transformed should prove useful for basic aspects of G. max molecular and genetic research. 相似文献