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131.
Joon-Goo Jung Yong Jae Lee Natarajan Velmurugan Young-Joon Ko Hyang-Sim Lee Ki Jun Jeong 《Journal of industrial microbiology & biotechnology》2013,40(7):705-713
For effective control of foot-and-mouth disease (FMD), the development of rapid diagnostic systems and vaccines are required against its etiological agent, FMD virus (FMDV). To accomplish this, efficient large-scale expression of the FMDV VP1 protein, with high solubility, needs to be optimized. We attempted to produce high levels of a serotype O FMDV VP1 epitope in Escherichia coli. We identified the subtype-independent serotype O FMDV VP1 epitope sequence and used it to construct a glutathione S-transferase (GST) fusion protein. For efficient production of the FMDV VP1 epitope fused to GST (VP1e–GST), four E. coli strains and three temperatures were examined. The conditions yielding the greatest level of VP1e–GST with highest solubility were achieved with E. coli BL21(DE3) at 25 °C. For high-level production, fed-batch cultures were conducted in 5-l bioreactors. When cells were induced at a high density and complex feeding solutions were supplied, approximately 11 g of VP1e–GST was obtained from a 2.9-l culture. Following purification, the VP1 epitope was used to immunize rabbits, and we confirmed that it induced an immune response. 相似文献
132.
Koeun Han Hee-Jin Jeong Joohee Sung Young Soo Keum Myeong-Cheoul Cho Jeong-Han Kim Jin-Kyung Kwon Byung-Dong Kim Byoung-Cheorl Kang 《Molecular breeding : new strategies in plant improvement》2013,31(3):537-548
Pungency in pepper (Capsicum annuum L.) has unique characteristics due to the alkaloid compound group, capsaicinoids, which includes capsaicin. Although capsaicinoids have been proved to have pharmacological and physiological effects on human health, the application of capsaicinoids has been limited because of their pungency. Capsinoids found in non-pungent peppers share closely related structures with capsaicinoids and show similar biological effects. Previous studies demonstrated that mutations in the p-AMT gene were related to the production of capsinoids; however, the pathway of capsinoid synthesis has not yet been fully elucidated. In this study, we performed genetic analysis to determine the mechanism of capsinoid synthesis using a F6 recombinant inbred line population. In this population, the presence/absence of capsinoids co-segregated with the genotype of the Pun1 locus, without exception. In addition, we screened the patterns of capsinoid synthesis and the correlation between the Pun1 locus and capsinoid synthesis in p-AMT mutant accessions. In Capsicum germplasms, we selected amino-acid-substituted mutants in the PLP binding domain of the p-AMT gene. Capsinoids were not synthesized with the recessive pun1 gene, regardless of the p-AMT genotype, and no relationship was found between p-AMT mutant type and capsinoid content. We concluded that the Pun1 gene, which is responsible for capsaicinoid synthesis, also controls capsinoid synthesis. 相似文献
133.
Jaekwang Jeong Ivonne Lisinski Anil K. G. Kadegowda Hyunsu Shin F. B. Peter Wooding Brian R. Daniels Jerome Schaack Ian H. Mather 《Traffic (Copenhagen, Denmark)》2013,14(9):974-986
Milk lipid is secreted by a unique process, during which triacylglycerol droplets bud from mammary cells coated with an outer bilayer of apical membrane. In all current schemes, the integral protein butyrophilin 1A1 (BTN) is postulated to serve as a transmembrane scaffold, which interacts either with itself or with the peripheral proteins, xanthine oxidoreductase (XOR) and possibly perilipin‐2 (PLIN2), to form an immobile bridging complex between the droplet and apical surface. In one such scheme, BTN on the surface of cytoplasmic lipid droplets interacts directly with BTN in the apical membrane without binding to either XOR or PLIN2. We tested these models using both biochemical and morphological approaches. BTN was concentrated in the apical membrane in all species examined and contained mature N‐linked glycans. We found no evidence for the association of unprocessed BTN with intracellular lipid droplets. BTN‐enhanced green fluorescent protein was highly mobile in areas of mouse milk‐lipid droplets that had not undergone post‐secretion changes, and endogenous mouse BTN comprised only 0.5–0.7% (w/w) of the total protein, i.e. over 50‐fold less than in the milk‐lipid droplets of cow and other species. These data are incompatible with models of milk‐lipid secretion in which BTN is the major component of an immobile global adhesive complex and suggest that interactions between BTN and other proteins at the time of secretion are more transient than previously predicted. The high mobility of BTN in lipid droplets marks it as a potential mobile signaling molecule in milk . 相似文献
134.
The dairy industry is a multi-billion dollar industry catering the nutritional needs of all age groups globally through the supply of milk. Clinical mastitis has a severe impact on udder tissue and is also an animal welfare issue. Moreover, it significantly reduces animal value and milk production. Mammary tissue damage reduces the number and activity of epithelial cells and consequently contributes to decreased milk production. The high incidence, low cure rate of this highly economic and sometimes deadly disease is an alarming for dairy sector as well as policy makers. Bovine mammary epithelial cells (MECs) and their stem cells are very important in milk production and bioengineering. The adult mammary epithelium consists of two main cell types; an inner layer of luminal epithelial cells, which produce the milk during lactation, and an outer layer of myoepithelial cells resting on a basement membrane, which are responsible for pushing the milk through the ductal network to the teat cistern. Inner layer of columner/luminal cells of bovine MECs, is characterized by cytokeratin18, 19 (CK18, CK19) and outer layer such as myoepithelial cells which are characterized by CK14, α-smooth muscle actin (α-SMA) and p63. Much work has been done in mouse and human, on mammary gland stem cell research, particularly in cancer therapy, but stem cell research in bovine is still in its infancy. Such stem/progenitor cell discoveries in human and mouse mammary gland bring some hope for application in bovines. These progenitors may be therapeutically adopted to correct the structural/cytological defects in the bovine udder due to mastitis. In the present review we focused on various kinds of stem/progenitor cells which can have therapeutic utility and their possibilities to use as a potential stem cell therapy in the management of bovine post-mastitis damage in orders to restore milk production. The possibilities of bovine mammary stem cell therapy offers significant potential for regeneration of tissues that can potentially replace/repair diseased and damaged tissue through differentiation into epithelial, myoepithelial and/or cuboidal/columnar cells in the udder with minimal risk of rejection and side effects. 相似文献
135.
Chung-Hwa Park Si Hyun Bae Hee Yeon Kim Ja Kyung Kim Eun Sun Jung Ho Jong Chun Myeong Jun Song Sung-Eun Lee Seok Goo Cho Jong Wook Lee Jong Young Choi Seung Kew Yoon Nam Ik Han Young Sok Lee 《Cytotherapy》2013,15(12):1571-1579
Background aimsMany rodent experiments and human studies on stem cell therapy have shown promising therapeutic approaches to liver diseases. We investigated the clinical outcomes of five patients with liver failure of various causes who received autologous CD34-depleted bone marrow-derived mononuclear cell (BM-MNC) transplantation, including mesenchymal stromal cells, through the hepatic artery.MethodsCD34-depleted BM-MNCs were obtained from five patients waiting for liver transplantation by bone marrow aspiration and using the CliniMACS CD34 Reagent System (Miltenyi Biotech, Bergisch Gladbach, Germany), and autologous hepatic artery infusion was performed. The causes of hepatic decompensation were hepatitis B virus (HBV), hepatitis C virus (HCV), propylthiouracil-induced toxic hepatitis and Wilson disease.ResultsSerum albumin levels improved 1 week after transplantation from 2.8 g/dL, 2.4 g/dL, 2.7 g/dL and 1.9 g/dL to 3.3 g/dL, 3.1 g/dL, 2.8 g/dL and 2.6 g/dL. Transient liver elastography data showed some change from 65 kPa, 33 kPa, 34.8 kPa and undetectable to 46.4 kPa, 19.8 kPa, 29.1 kPa and 67.8 kPa at 4 weeks after transplantation in a patient with Wilson disease, a patient with HCV, and two patients with HBV. Ascites decreased in two patients. One of the patients with HBV underwent liver transplantation 4 months after the infusion, and the hepatic progenitor markers (cytokeratin [CD]-7, CD-8, CD-9, CD-18, CD-19, c-Kit and epithelial cell adhesion molecule [EpCAM]) were highly expressed in the explanted liver.ConclusionsSerum albumin levels, liver stiffness, liver volume, subjective healthiness and quality of life improved in the study patients. Although these findings were observed in a small population, the results may suggest a promising future for autologous CD34-depleted BM-MNC transplantation as a bridge to liver transplantation in patients with liver failure. 相似文献
136.
Sangwoo Kim Kyowon Jeong Kunal Bhutani Jeong Ho Lee Anand Patel Eric Scott Hojung Nam Hayan Lee Joseph G Gleeson Vineet Bafna 《Genome biology》2013,14(8):R90
Detection of somatic variation using sequence from disease-control matched data sets is a critical first step. In many cases including cancer, however, it is hard to isolate pure disease tissue, and the impurity hinders accurate mutation analysis by disrupting overall allele frequencies. Here, we propose a new method, Virmid, that explicitly determines the level of impurity in the sample, and uses it for improved detection of somatic variation. Extensive tests on simulated and real sequencing data from breast cancer and hemimegalencephaly demonstrate the power of our model. A software implementation of our method is available at http://sourceforge.net/projects/virmid/. 相似文献
137.
Development of induced pluripotent stem cell (iPSC) technology introduced a novel way to derive pluripotent stem cells, but the genetic manipulation required to generate iPSCs may lead to uncontrolled tumorigenesis of the established cells and thus limit clinical feasibility of the technology. Numerous attempts have been made to date, and alternative reprogramming of somatic cells to reactivate cellular plasticity after differentiation has been suggested. As a result, it had become clear that cell-to-cell interactions and specific acellular environments can be utilized for somatic cell reprogramming. In our previous studies, embryonic stem cell (ESC)-like cells could be derived from transforming ovarian cells and fetal fibroblasts by cell-to-cell interaction or specific cell-mediated microenvironmental factor(s). This cellular event was induced without undertaking genetic manipulation of progenitor cells. Several differences were found between the cellular properties of niche-induced, ESC-like cells and those of genetically manipulated iPSCs and the referenced ESCs. Thus, we provided evidence that terminally differentiated somatic cells either acquire pluripotency-like activity or possess cellular and genetic plasticity under a specific microenvironment and/or cell-to-cell interaction. In this minireview, we discuss derivation of stem cell-like cells under specific microenvironmental conditions in terms of technical perspectives and limitations. 相似文献
138.
Eun-Young Won Mi-Kyung Yoon Sang-Woo Kim Youngae Jung Hyun-Whee Bae Daeyoup Lee Sung Goo Park Chul-Ho Lee Geum-Sook Hwang Seung-Wook Chi 《PloS one》2013,8(10)
Despite the numerous metabolic studies on obesity, gender bias in obesity has rarely been investigated. Here, we report the metabolomic analysis of obesity by using leptin-deficient ob/ob mice based on the gender. Metabolomic analyses of urine and serum from ob/ob mice compared with those from C57BL/6J lean mice, based on the 1H NMR spectroscopy in combination with multivariate statistical analysis, revealed clear metabolic differences between obese and lean mice. We also identified 48 urine and 22 serum metabolites that were statistically significantly altered in obese mice compared to lean controls. These metabolites are involved in amino acid metabolism (leucine, alanine, ariginine, lysine, and methionine), tricarbocylic acid cycle and glucose metabolism (pyruvate, citrate, glycolate, acetoacetate, and acetone), lipid metabolism (cholesterol and carnitine), creatine metabolism (creatine and creatinine), and gut-microbiome-derived metabolism (choline, TMAO, hippurate, p-cresol, isobutyrate, 2-hydroxyisobutyrate, methylamine, and trigonelline). Notably, our metabolomic studies showed distinct gender variations. The obese male mice metabolism was specifically associated with insulin signaling, whereas the obese female mice metabolism was associated with lipid metabolism. Taken together, our study identifies the biomarker signature for obesity in ob/ob mice and provides biochemical insights into the metabolic alteration in obesity based on gender. 相似文献
139.
Jaeuk Hwang Jieun E. Kim Marc J. Kaufman Perry F. Renshaw Sujung Yoon Deborah A. Yurgelun-Todd Yera Choi Chansoo Jun In Kyoon Lyoo 《PloS one》2013,8(10)
Objective
Adolescent-onset exposure to highly addictive substances such as opiates may induce far-reaching deleterious effects on later mental and physical health. However, little is known about the neurodevelopmental basis for adolescent-onset opiate dependence. Here we examined whether having an abnormally large cavum septum pellucidum (CSP), a putative marker of limbic structural maldevelopment, is associated with opiate dependence particularly beginning in adolescence.Method
The overall length of the CSP and the prevalence of abnormal enlargement of the CSP were assessed and compared in 65 opiate-dependent subjects (41 adolescent-onset opiate users and 24 adult-onset opiate users) and 67 healthy subjects.Results
Opiate-dependent subjects showed a greater prevalence of abnormal CSP enlargement relative to healthy subjects (odds ratio [OR]=3.64, p=0.034). The overall CSP length of adolescent-onset opiate-dependent subjects was greater, as compared not only with healthy subjects (F1,104=11.03, p=0.001) but also with those who began opiate use during adulthood (F1,61=4.43, p=0.039).Conclusions
The current findings provide the first evidence that abnormal CSP enlargement, which reflects limbic system dysgenesis of neurodevelopmental origin, may be linked to later development of opiate dependence. In addition, a greater CSP length, which indicates more severe limbic abnormalities, appears to confer higher risk for earlier onset of opiate use. 相似文献140.
To determine whether chromosomes in the porcine first polar body (PB1) can complete the second meiotic division and subsequently undergo normal pre-implantation embryonic development, we examined the developmental competence of PB1 chromosomes injected into enucleated MII stage oocytes by nuclear transfer method (chromosome replacement group, CR group). After parthenogenetic activation (PA) or in vitro fertilization (IVF), the cleavage rate of reconstructed oocytes in the IVF group (CR-IVF group, 36.4 ± 3.2%) and PA group (CR-PA group, 50.8 ± 4.2%) were significantly lower than that of control groups in which normal MII oocytes were subjected to IVF (MII-IVF group, 75.8 ± 1.5%) and PA (MII-PA group, 86.9 ± 3.7%). Unfertilized rates was significantly higher in the CR-IVF group (48.6 ± 3.3%) than in the MII-IVF group (13.1 ± 3.4%). The blastocyst formation rate was 8.3 ± 1.9% in the CR-PA group, whereas no blastocyst formation was observed in the CR-IVF group. To produce tetraploid parthenogenetic embryos, intact MII stage oocytes injected with PB1chromosomes were electrically stimulated, treated with 7.5 μg/mL cytochalasin B for 3 h (MII oocyte + PB1 + CB group), and then cultured without cytochalasin B. The average cleavage rate of reconstructed oocytes was 72.5% (48 of 66), and the blastocyst formation rate was 18.7% (9 of 48). Chromosome analysis showed similar proportions of haploid and diploid cells in the control (normal MII oocytes) and CR groups after PA; overall, 23.6% of blastocysts were tetraploid in the MII oocyte + PB1 + CB group. These results demonstrate that chromosomes in PB1 can participate in normal pre-implantation embryonic development when injected into enucleated MII stage oocytes, and that tetraploid PA blastocysts are produced (although at a low proportion) when PB1 chromosomes are injected into intact MII stage oocytes. 相似文献