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861.
Lee Changsu Song Hye Seon Lee Se Hee Kim Joon Yong Rhee Jin-Kyu Roh Seong Woon 《Archives of microbiology》2021,203(1):261-268
Archives of Microbiology - Extremely halophilic archaea (haloarchaea) belonging to the phylum Euryarchaeota have been found in high-salinity environments. In this study, Halarchaeum sp. CBA1220,... 相似文献
862.
Bone marrow-derived mesenchymal stem cells (BMSCs) are of particular interest in the field of tissue engineering because of
their potential to differentiate into osteoblasts, chondrocytes, and neuronal cells. In order to promote the differentiation
of BMSCs into specific cell types, appropriate scaffold biomaterials and bioactive molecules that can support the differentiation
of BMSCs into specific cell types are needed. We hypothesized that β-mercaptoethanol (BME), which has been reported to induce
the differentiation of BMSCs into neural-like cells, promotes BMSCs to differentiate into neural-like cells when BME is added
to polymeric scaffolds containing the BMSCs. We fabricated biocompatible film shaped scaffolds composed of poly(lacti-co-glycolic)
acid (PLGA) and various concentrations of BME to confirm that BME-promoted differentiation of BMSCs is concentration-dependent.
Cell proliferation increased as the BME concentration in the films increased at the early stage, and the proliferation rate
remained similar on the PLGA films for 3 weeks following the BMSC seeding. The expression of neuronal markers in differentiated
BMSCs was assessed by RT-PCR. At 2- and 3-week time-points, mRNA expression of neurofilament and neuron specific enolase was
significantly increased in PLGA/BME films containing 400 μM BME compared to PLGA films. Thus, we have identified BMSC-seeded
PLGA/BME films with 200 μM and 400 μM BME as potentially useful candidates for neural tissue engineering applications by promoting
BMSC proliferation and differentiation towards neural-like cells. 相似文献
863.
The identification of true causal loci to unravel the statistical evidence of genotype-phenotype correlations and the biological
relevance of selected single-nucleotide polymorphisms (SNPs) is a challenging issue in genome-wide association studies (GWAS).
Here, we introduced a novel method for the prioritization of SNPs based on p-values from GWAS. The method uses functional evidence from populations, including phenotype-associated gene expressions. Based on
the concept of genetic interactions, such as perturbation of gene expression by genetic variation, phenotype and gene expression
related SNPs were prioritized by adjusting the p-values of SNPs. We applied our method to GWAS data related to drug-induced cytotoxicity. Then, we prioritized loci that potentially
play a role in druginduced cytotoxicity. By generating an interaction model, our approach allowed us not only to identify
causal loci, but also to find intermediate nodes that regulate the flow of information among causal loci, perturbed gene expression,
and resulting phenotypic variation. 相似文献
864.
Putcharoen O Lee SH Henrich TJ Hu Z Vanichanan J Coakley E Greaves W Gulick RM Kuritzkes DR Tsibris AM 《Journal of virology》2012,86(2):1119-1128
HIV CCR5 antagonists select for env gene mutations that enable virus entry via drug-bound coreceptor. To investigate the mechanisms responsible for viral adaptation to drug-bound coreceptor-mediated entry, we studied viral isolates from three participants who developed CCR5 antagonist resistance during treatment with vicriviroc (VCV), an investigational small-molecule CCR5 antagonist. VCV-sensitive and -resistant viruses were isolated from one HIV subtype C- and two subtype B-infected participants; VCV-resistant isolates had mutations in the V3 loop of gp120 and were cross-resistant to TAK-779, an investigational antagonist, and maraviroc (MVC). All three resistant isolates contained a 306P mutation but had variable mutations elsewhere in the V3 stem. We used a virus-cell β-lactamase (BlaM) fusion assay to determine the entry kinetics of recombinant viruses that incorporated full-length VCV-sensitive and -resistant envelopes. VCV-resistant isolates exhibited delayed entry rates in the absence of drug, relative to pretherapy VCV-sensitive isolates. The addition of drug corrected these delays. These findings were generalizable across target cell types with a range of CD4 and CCR5 surface densities and were observed when either population-derived or clonal envelopes were used to construct recombinant viruses. V3 loop mutations alone were sufficient to restore virus entry in the presence of drug, and the accumulation of V3 mutations during VCV therapy led to progressively higher rates of viral entry. We propose that the restoration of pre-CCR5 antagonist therapy HIV entry kinetics drives the selection of V3 loop mutations and may represent a common mechanism that underlies the emergence of CCR5 antagonist resistance. 相似文献
865.
Xiao H Zhang L Zhou H Lee JM Garon EB Wong DT 《Molecular & cellular proteomics : MCP》2012,11(2):M111.012112
Lung cancer is often asymptomatic or causes only nonspecific symptoms in its early stages. Early detection represents one of the most promising approaches to reduce the growing lung cancer burden. Human saliva is an attractive diagnostic fluid because its collection is less invasive than that of tissue or blood. Profiling of proteins in saliva over the course of disease progression could reveal potential biomarkers indicative of oral or systematic diseases, which may be used extensively in future medical diagnostics. There were 72 subjects enrolled in this study for saliva sample collection according to the approved protocol. Two-dimensional difference gel electrophoresis combined with MS was the platform for salivary proteome separation, quantification, and identification from two pooled samples. Candidate proteomic biomarkers were verified and prevalidated by using immunoassay methods. There were 16 candidate protein biomarkers discovered by two-dimensional difference gel electrophoresis and MS. Three proteins were further verified in the discovery sample set, prevalidation sample set, and lung cancer cell lines. The discriminatory power of these candidate biomarkers in lung cancer patients and healthy control subjects can reach 88.5% sensitivity and 92.3% specificity with AUC = 0.90. This preliminary data report demonstrates that proteomic biomarkers are present in human saliva when people develop lung cancer. The discriminatory power of these candidate biomarkers indicate that a simple saliva test might be established for lung cancer clinical screening and detection. 相似文献
866.
GRP78, a master regulator of the unfolded protein response (UPR) and cell signaling, is required for inner cell mass survival during early embryonic development. However, little is known about its role in adult hematopoietic stem cells (HSCs) and hematopoiesis. Here we generated a conditional knockout mouse model that acutely deletes Grp78 in the adult hematopoietic system. Acute GRP78 ablation resulted in a significant reduction of HSCs, common lymphoid and myeloid progenitors, and lymphoid cell populations in the mutant mice. The GRP78-null induced reduction of the HSC pool could be attributed to increased apoptosis. Chimeric mice with Grp78 deletion only in the hematopoietic cells also showed a loss of HSCs and lymphopenia, suggesting a cell intrinsic effect. Analysis of GRP78 deficient bone marrow (BM) cells showed constitutive activation of all the major UPR signaling pathways, including activation of eIF2α, ATF6, xbp-1 splicing, as well as caspase activation. A multiplex cytokine assay further revealed alteration in select cytokine and chemokine serum levels in the mutant mice. Collectively, these studies demonstrate that GRP78 plays a pleiotropic role in BM cells and contributes to HSC survival and the maintenance of the lymphoid lineage. 相似文献
867.
J. T. Trevors J. D. van Elsas H. Lee A. C. Wolters 《Applied microbiology and biotechnology》1993,39(4-5):637-643
Alginate-encapsulated and unencapsulated cells of Pseudomonas fluorescens Rsf were introduced into soil microcosms with and without wheat plants to evaluate bacterial survival and colonization of the rhizoplane and rhizosphere. Encapsualtion of cells in alginate amended with skim milk or with skim milk plus bentonite clay significantly enchanced long-term survival of the cells. There was a negligible effect on long-term bacterial survival when cells were encapsulated in alginate amended with TY medium or soil extract, as compared to water. Drying of beads resulted in a significant reduction in bacterial viability. After addition to soil, cells in dried beads increased in numbers and exhibited stable population densities, whereas cells added in moist beads showed stable dynamics at a higher level. Cells encapsulated in dried beads or fresh beads survived better than unencapsulated cells added to soil. Both cells in moist and dried alginate beads also survide a dry/wet cycle in soil, whereas unencapsulated cells were sensitive to these moisture fluctuations. Shortly after inoculation and 63 days after this, cells from moist beads colonized wheat roots at significantly higher levels than unencapsulated cells, whereas cells in dried beads did so at levels similat to unencapsulated cells. Cells in beads initially placed at different distance from developing root mat were able to move towards and colonize the rhizosphere, at levels of roughly 104 to 106 colony-forming units fo P. fluorescens R2f per gram of dry soil.
Correspondence to: J. T. Trevors or J. D. van Elsas 相似文献
868.
MORTALITY OF SEA OTTERS IN PRINCE WILLIAM SOUND FOLLOWING THE EXXON VALDEZ OIL SPILL 总被引:1,自引:0,他引:1
Abstract: This paper presents an estimate of the total number of sea otters that died as a direct consequence of the oil spill that occurred when the T/V Exxon Valdez grounded in Prince William Sound, Alaska on 24 March 1989. We compared sea otter counts conducted from small boats throughout the Sound during the summers of 1984 and 1985 to counts made after the spill during the summer of 1989. We used ratio estimators, corrected for sighting probability, to calculate otter densities and population estimates for portions of the Sound affected by the oil spill. We estimated the otter population in the portion of Prince William Sound affected by the oil was 6,546 at the time of the spill and that the post-spill population in the summer of 1989 was 3,898, yielding a loss estimate of approximately 2,650. Bootstrapping techniques were used to approximate confidence limits on the loss estimate of about 500–5,000 otters. The wide confidence limits are a result of the complex scheme required to estimate losses and limitations of the data. Despite the uncertainty of the loss estimate it is clear that a significant fraction of the otters in the spill zone survived. We observed otters persisting in relatively clean embayments throughout the oil spill zone suggesting that the highly convoluted coastline of Prince William Sound produced refuges that allowed some sea otters in the oil spill area to survive. 相似文献
869.
Cellular senescence is a physiological program of irreversible growth arrest that is considered to play an important role in tumor suppression. Recent studies demonstrated that senescent cells secrete multiple growth regulatory proteins that could alter the behavior of neighboring cells. In this study, we investigated the effect of secretory proteins from ionizing radiation (IR) induced senescent tumor cells on normal and tumor cells. Conditioned medium (CM) from IR-induced senescent MCF7 cells significantly increased cell proliferation, invasion, migration, and wound healing activity in MCF7 cells and HUVECs. Comparative proteomics analysis revealed 24 differentially secreted protein spots including Raf kinase inhibitor protein (RKIP), α-Enolase, AKAP9, and MARK4, and the findings were confirmed by Western blot analysis of IR-induced senescent cancer cells. We found that RKIP was secreted via the classical pathway, and the transfection of small interfering RNA against RKIP suppressed CM-induced migration in MCF7 cells. Treatment with recombinant human RKIP increased the migratory activity of MCF7 cells. Taken together, our results demonstrate that the senescence-associated secretory protein RKIP could be the principal target to prevent the potential effects of the secretome from IR-induced senescent tumor cells on neighboring cell migration. 相似文献
870.
Miguel A. Providenti Hung Lee Jack T. Trevors 《Journal of industrial microbiology & biotechnology》1993,12(6):379-395
Summary The focus of this review is to examine some of the reasons biodegradation may not take place in the environment even though its occurrence in the laboratory has been demonstrated. Some approaches for dealing with chemical persistence will be discussed. In addition, the potential of bioremediation as an in situ clean-up technology will be considered. 相似文献