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31.
Yochan Joung Haneul Kim Beom-Il Lee Heeyoung Kang Tae Yong Jang O-Seob Kwon Kiseong Joh 《Journal of microbiology (Seoul, Korea)》2013,51(4):531-535
A Gram-staining-negative, rod-shaped and red-pigmented bacterial strain, HMD3125T, was isolated from a solar saltern in Jeungdo, Republic of Korea. A phylogenetic tree based on 16S rRNA gene sequences showed that strain HMD3125T formed a lineage within the genus Pontibacter and was similar to Pontibacter salisaro (96.1%) and P. korlensis (95.3%). The major fatty acids of strain HMD3125T were summed feature 4 (comprising iso-C17:1 I and/or anteiso-C17:1 B; 30.4%), iso-C15:0 (20.4%) and iso-C17:0 3OH (17.2%). The polar lipid profile of HMD3125T consisted of the phosphatidylethanolamine, four unidentified polar lipids, unidentified phospholipid, unidentified aminolipid and unidentified aminophospholipid. Strain HMD3125T contained MK-7 as the predominant menaquinone and sym-homospermidine as the major polyamine. The DNA G+C content of strain HMD3125T was 45.6 mol%. Strain HMD3125T assigned as a novel species in the genus Pontibacter, for which the name Pontibacter jeungdoensis sp. nov. is proposed. The type strain is HMD3125T (=KCTC 23156T =CECT 7710T). 相似文献
32.
Changon Seo Yun-Hyeok Choi Jong Seog Ahn Joung Han Yim Hong Kum Lee 《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):1133-1137
The selective inhibition of PTP1B has been widely recognized as a potential drug target for the treatment of type 2 diabetes and obesity. In the course of screening for PTP1B inhibitory natural products, the MeOH extract of the dried sample of the Antarctic lichen Umbilicaria antarctica was found to exhibit significant inhibitory effect, and the bioassay-guided fractionation and purification afforded three related lichen metabolites 1-3. Compounds 1-3 were identified as gyrophoric acid (1), lecanoric acid (2), and methyl orsellinate (3) mainly by analysis of NMR and MS data. These compounds inhibited PTP1B activity with 50% inhibitory concentration values of 3.6 ± 0.04 μM, 31 ± 2.7 μM, and 277 ± 8.6 μM, respectively. Furthermore, the kinetic analysis of PTP1B inhibition by compound 1 suggested that the compound inhibited PTP1B activity in a non-competitive manner. 相似文献
33.
Choong Je Ma Won Joo Jung Ki Yong Lee Young Choong Kim 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):676-679
The n-butanol (n-BuOH) fraction of Orostachys japonicus A. Berger (Crassulaceae) significantly inhibited calpain activity. Through the activity-guided isolation from the n-BuOH fraction, herbacetin 8-O-α-D-ribopyranoside (1), kaempferol (2), quercetin (3), afzelin (4), astragalin (5), isoquercetin (6) and quercitrin (7) were obtained. Their structures were determined by spectroscopic techniques. Among them, compound 3 and 5 had significant calpain inhibitory activities. 相似文献
34.
Three, six, nine, and twelve V of electric pulse (EP) was applied to a culture of Weissella cibaria SKkimchi1 in MRS medium and kimchi-making culture (KMC). Viable cell number of SKkimchi1 in MRS medium was decreased in proportion to pulse intensity but that of bacteria in KMC was not. Lactic acid and ethanol produced by SKkimchi1 tended to be decreased in proportion to EP intensity but acetic acid was proportionally increased to EP intensity. Lactic acid, ethanol, and propionic acid produced in KMC were proportionally decreased, but acetic acid was proportionally increased to the EP intensity. Bacterial community and diversity in KMC were analyzed based on culture time by a temperature gradient gel electrophoresis (TGGE) technique. Most bacterial communities grown in freshly prepared kimchi belonged to Bacillus genus. Lactic acid bacteria responsible for kimchi fermentation began to grow on day 4, and were completely substituted for Bacillus genus on day 8, but some Bacillus genus began to grow again on day 12. However, bacterial community diversities were not different based on varying EP intensity. 相似文献
35.
Jun Seo Goo Yo Na Kim Kyung Mi Choi In Sik Hwang Ji Eun Kim Young Ju Lee Moon Hwa Kwak Sun Bo Shim Seung Wan Jee Chul Joo Lim Je Kyung Seong Dae Youn Hwang 《Clinical proteomics》2013,10(1):10
Background
To characterize changes in global protein expression in kidneys of transgenic rats overexpressing human selenoprotein M (SelM) in response to increased bioabivility of selenium (Sel), total proteins extracted from kidneys of 10-week-old CMV/hSelM Tg and wild-type rats were separated by 2-dimensional gel electrophoresis and measured for changes in expression.Results
Ten and three proteins showing high antioxidant enzymatic activity were up- and down-regulated, respectively, in SelM-overexpressing CMV/hSelM Tg rats compared to controls based on an arbitrary 2-fold difference. Up-regulated proteins included LAP3, BAIAP2L1, CRP2, CD73 antigen, PDGF D, KIAA143 homolog, PRPPS-AP2, ZFP313, HSP-60, and N-WASP, whereas down-regulated proteins included ALKDH3, rMCP-3, and STC-1. After Sel treatment, five of the up-regulated proteins were significantly increased in expression in wild-type rats, whereas there were no changes in CMV/hSelM Tg rats. Only two of the down-regulated proteins showed reduced expression in wild-type and Tg rats after Sel treatment.Conclusions
These results show the primary novel biological evidences that new functional protein groups and individual proteins in kidneys of Tg rats relate to Sel biology including the response to Sel treatment and SelM expression. 相似文献36.
37.
Byung-Im So Yi-Sun Song Cheng-Hu Fang Jun-Young Park Yonggu Lee Jeong Hun Shin Hyuck Kim Kyung-Soo Kim 《PloS one》2013,8(10)
Background
The protective effects of granulocyte colony-stimulating factor (G-CSF) have been demonstrated in a variety of renal disease models. However, the influence of G-CSF on diabetic nephropathy (DN) remains to be examined. In this study, we investigated the effect of G-CSF on DN and its possible mechanisms in a rat model.Methods
Otsuka Long-Evans Tokushima Fatty (OLETF) rats with early DN were administered G-CSF or saline intraperitoneally. Urine albumin creatinine ratio (UACR), creatinine clearance, mesangial matrix expansion, glomerular basement membrane (GBM) thickness, and podocyte foot process width (FPW) were measured. The levels of interleukin (IL)-1β, transforming growth factor (TGF)-β1, and type IV collagen genes expression in kidney tissue were also evaluated. To elucidate the mechanisms underlying G-CSF effects, we also assessed the expression of G-CSF receptor (G-CSFR) in glomeruli as well as mobilization of bone marrow (BM) cells to glomeruli using sex-mismatched BM transplantation.Results
After four weeks of treatment, UACR was lower in the G-CSF treatment group than in the saline group (p<0.05), as were mesangial matrix expansion, GBM thickness, and FPW (p<0.05). In addition, the expression of TGF-β1 and type IV collagen and IL-1β levels was lower in the G-CSF treatment group (p<0.05). G-CSFR was not present in glomerular cells, and G-CSF treatment increased the number of BM-derived cells in glomeruli (p<0.05).Conclusions
G-CSF can prevent the progression of DN in OLETF rats and its effects may be due to mobilization of BM cells rather than being a direct effect. 相似文献38.
Background
The progression of hepatic fibrosis may result in decompensated hepatic failure with cirrhosis, liver related events (LRE) such as ascites, variceal bleeding, and death after successful and timely Kasai hepatoportoenterostomy (HPE) in biliary atresia. The aim of this study is to suggest clinical benefit of the liver stiffness measurement (LSM) using transient elastography at 3 months after the Kasai operation to predict LRE.Methods
Between January 2007 and December 2011, 69 eligible biliary atresia patients who underwent Kasai HPE and performed transient elastography before and 3 months after HPE were included. The occurrences of LRE were analyzed for all patients. All patients were divided into 2 groups (with and without LRE) for comparison. Multivariate analysis was used to detect the independent risk factors of LRE. The area under the receiver operation characteristics curve (AUROC) was used to establish the LSM optimal cutoff value of 3 months after Kasai operation in predicting LRE.Results
LSM value, aminotransferase, albumin, bilirubin, and PT-INR significantly differed among the two groups. Multivariate analysis demonstrated LSM value as the most powerful independent factor of the development of LRE. The cut-off value of 19.9 kPa was calculated to be optimal for predicting LRE development with total sensitivity and specificity of 1.804. AUROC resulted in 0.943, with sensitivity of 85.3% and specificity of 95.2%.Conclusions
The LSM value of 3 months after Kasai HPE can be a useful predictor of LRE development. 相似文献39.
Jung Ok Park Do‐Young Choi Dong‐Sic Choi Hee Joung Kim Jeong Won Kang Jae Hun Jung Jeong Hwa Lee Jayoung Kim Michael R. Freeman Kye Young Lee Yong Song Gho Kwang Pyo Kim 《Proteomics》2013,13(14):2125-2134
Microvesicles (MVs, also known as exosomes, ectosomes, microparticles) are released by various cancer cells, including lung, colorectal, and prostate carcinoma cells. MVs released from tumor cells and other sources accumulate in the circulation and in pleural effusion. Although recent studies have shown that MVs play multiple roles in tumor progression, the potential pathological roles of MV in pleural effusion, and their protein composition, are still unknown. In this study, we report the first global proteomic analysis of highly purified MVs derived from human nonsmall cell lung cancer (NSCLC) pleural effusion. Using nano‐LC–MS/MS following 1D SDS‐PAGE separation, we identified a total of 912 MV proteins with high confidence. Three independent experiments on three patients showed that MV proteins from PE were distinct from MV obtained from other malignancies. Bioinformatics analyses of the MS data identified pathologically relevant proteins and potential diagnostic makers for NSCLC, including lung‐enriched surface antigens and proteins related to epidermal growth factor receptor signaling. These findings provide new insight into the diverse functions of MVs in cancer progression and will aid in the development of novel diagnostic tools for NSCLC. 相似文献
40.
Prions are self-propagating conformations of proteins that can cause heritable phenotypic traits. Most yeast prions contain glutamine (Q)/asparagine (N)-rich domains that facilitate the accumulation of the protein into amyloid-like aggregates. Efficient transmission of these infectious aggregates to daughter cells requires that chaperones, including Hsp104 and Sis1, continually sever the aggregates into smaller “seeds.” We previously identified 11 proteins with Q/N-rich domains that, when overproduced, facilitate the de novo aggregation of the Sup35 protein into the [PSI
+] prion state. Here, we show that overexpression of many of the same 11 Q/N-rich proteins can also destabilize pre-existing [PSI
+] or [URE3] prions. We explore in detail the events leading to the loss (curing) of [PSI+] by the overexpression of one of these proteins, the Q/N-rich domain of Pin4, which causes Sup35 aggregates to increase in size and decrease in transmissibility to daughter cells. We show that the Pin4 Q/N-rich domain sequesters Hsp104 and Sis1 chaperones away from the diffuse cytoplasmic pool. Thus, a mechanism by which heterologous Q/N-rich proteins impair prion propagation appears to be the loss of cytoplasmic Hsp104 and Sis1 available to sever [PSI
+]. 相似文献