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排序方式: 共有163条查询结果,搜索用时 15 毫秒
1.
Recent studies have shown that tumour cells express tumour necrosis factor-inducible gene 6 (TSG-6) and its protein, which is known to play a key role in regulating excessive immune responses and proliferation and growth of mesenchymal stem cells (MSCs). It has not been confirmed whether the inhibition of TSG-6 for tumour cells can suppress tumour cell growth and regulate the activation of immune cells in the tumour microenvironment (TME). TSG-6-specific small interfering RNA was transfected into canine and human breast cancer cells (CIPp, CIPm and BT-20). TSG-6-down-regulated (siTSG-6) cells showed decreased cell proliferation, migration, and invasion abilities. Decreased mRNA expressions of NF-κB, STAT3 and Sox2, confirming that TSG-6 is an upper factor governing tumour growth and metastasis. Notably, siTSG-6 cells showed significantly decreased expression levels of CD44 and PD-L1. Direct and indirect co-culture of canine peripheral blood mononuclear cells (cPBMCs) and the siTSG-6 cells showed significant activation in M1 type macrophages and cytotoxic T cells. They also showed a tendency to decrease in the expression of CTLA-4 and increase in the expression of PD-1. In conclusion, this study suggests that the down-regulation of TSG-6 in breast cancer cells could not only suppress tumour growth and metastasis, and but also regulate TME. Since modulation of immune checkpoint proteins occurs in both tumour cells and immune cells, inhibiting TSG-6 and its protein within the TME could be novel therapeutic target for anticancer treatment. 相似文献
2.
Since the discovery of penicillin in 1928 and throughout the ‘age of antibiotics’ from the 1940s until the 1980s, the detection of novel antibiotics was restricted by lack of knowledge about the distribution and ecology of antibiotic producers in nature. The discovery that a phenazine compound produced by Pseudomonas bacteria could suppress soilborne plant pathogens, and its recovery from rhizosphere soil in 1990, provided the first incontrovertible evidence that natural metabolites could control plant pathogens in the environment and opened a new era in biological control by root‐associated rhizobacteria. More recently, the advent of genomics, the availability of highly sensitive bioanalytical instrumentation, and the discovery of protective endophytes have accelerated progress toward overcoming many of the impediments that until now have limited the exploitation of beneficial plant‐associated microbes to enhance agricultural sustainability. Here, we present key developments that have established the importance of these microbes in the control of pathogens, discuss concepts resulting from the exploration of classical model systems, and highlight advances emerging from ongoing investigations. © 2019 Society of Chemical Industry 相似文献
3.
B Gui YY Shim RS Datla PS Covello SL Stone MJ Reaney 《Journal of agricultural and food chemistry》2012,60(35):8571-8579
Cyclolinopeptides are a group of naturally occurring hydrophobic cyclic peptides found in flaxseed and flax oil that have immunosuppressive activity. This study describes the measurement of flaxseed cyclolinopeptide concentrations using an internal standard HPLC method. In addition, the concentration of cyclolinopeptides in the seed of Canadian flax cultivars grown at two locations over two years is reported. The data are consistent with the formation of flaxseed cyclolinopeptides from two ribosome-derived precursors. Each precursor protein includes the sequences corresponding to three cyclolinopeptides from which those cyclolinopeptides are presumably derived by precursor processing. The concentrations of cyclolinopeptides C and E, which are encoded by the same gene sequence, are highly correlated, and the concentrations of cyclolinopeptides D, F, and G, which are encoded by a second gene sequence, are also highly correlated. The strong correlation between the cyclolinopeptides arising from the same gene may prove to be important in understanding how peptide concentration is controlled. Additional research may lead to approaches to improve flax either as a platform for peptide production or as a source of oil with improved drying properties and flavor. 相似文献
4.
[目的]研究贵州省人口与建设用地变化的关系,以促进土地资源优化配置。[方法]利用贵州省2000—2017年城乡人口及建设用地数据,采用脱钩模型和GIS空间分析方法,研究城乡人地关系演化过程。[结果]贵州省城镇人口持续增加,乡村人口逐年减少;城乡建设用地面积不断扩大,城镇和乡村建设用地同向增长。2000—2008年,贵州省城乡人口变化与建设用地扩张关系为强负脱勾类型,乡村人口与乡村建设用地变化为强负脱钩类型,城镇人口与城镇建设用地变化为扩张负脱钩类型。农村人口减少伴随着建设用地增加,农村人地关系处于较不合理状态;城镇人口和建设用地二者均增长,但建设用地增幅快于人口增幅。[结论]贵州省应积极推动农村宅基地流转,提高城乡建设用地集约利用水平,促进城乡融合。 相似文献
5.
Alexander de Oliveira El-Warrak Mouhamed Rouma Audrey Amoroso Soren R. Boysen Younés Chorfi 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(12):1285-1288
This study compared vitamin A, vitamin E, selenium (Se), and L-lactate in blood and synovial fluid in 2 groups of 6 dogs; a control group (without OA) and an osteoarthritic group with spontaneous cranial cruciate ligament rupture and OA. Concentrations of vitamin E were significantly higher in serum than in synovial fluid in both OA (P = 0.006) and control (P = 0.0008) groups. Vitamin E concentration in synovial fluid was significantly higher in the OA group than in the control group (P = 0.009). Concentrations of Se were significantly higher in serum than in synovial fluid in both OA (P = 0.003) and control (P = 0.0006) groups. There were no significant differences in levels of Se, vitamin A, and L-lactate between the 2 groups. This is the first study to show an increased concentration of vitamin E in the synovial fluid of dogs with OA compared with dogs that did not have OA. 相似文献
6.
Hang Thi Nguyen Ki-Hyun Kim Min-Young Kim Sungmin Hong Yong-Hoon Youn Zang-Ho Shon Jeong Soon Lee 《Water, air, and soil pollution》2007,185(1-4):149-164
In order to investigate the regional background concentration levels of mercury (Hg), measurements were routinely recorded on An-Myun Island off the coast of Korea (December 2004 to April 2006). The mean concentration of Hg computed from the entire measurement period was 4.61?±?2.21 ng m?3 with a range of 0.10–25.4 ng m?3 (N?=?10,485). Using these data, we inspected various aspects of Hg behavior from the relatively remote island of An-Myun in Korea. Inspection of the seasonal patterns of Hg indicated that its concentration levels generally peaked in spring, while reached a minimum in summer. The summertime deficiency of Hg along with the lack of diurnal variation suggests that the environmental behavior of Hg at the study site was strongly suppressed by heavy precipitation during specific period. The diurnal variations of Hg, typically characterized by a relative daytime dominance, are distinguishable between seasons so that such patterns disappear during the summer. The results of our analysis, when inspected in terms of long-range transport of airborne pollutants, imply that Hg concentration levels can be affected intensively by trans-boundary input processes over certain period of time. Its springtime dominance hence suggests the combined effects of various local source processes and the meteorological conditions favorable for the massive air mass transport phenomenon (such as Asian Dust storms) during that time period. 相似文献
7.
Sung-Hun MIN Bong-Seok SONG Ji-Yeong YEON Jin-Woo KIM Jung-Ho BAE Soo-Yong PARK Yong-Hee LEE Kyu-Tae CHANG Deog-Bon KOO 《The Journal of reproduction and development》2014,60(1):21-27
Bovine somatic cell nuclear transfer (SCNT) is an important and powerful tool for basic
research and biomedical and agricultural applications, however, the efficiency of SCNT has
remained extremely low. In this study, we investigated the effects of cathepsin B
inhibitor (E-64) supplementation of culture medium on in vitro
development of bovine SCNT embryos. We initially used three concentrations of E-64 (0.1,
0.5, 1.0 μm), among which 0.5 μm resulted in the highest rate of blastocysts production after in
vitro fertilization (IVF), and was therefore used for further experiments.
Blastocyst development of SCNT embryos in the E-64 treatment group also increased relative
to the control. Moreover, the cryosurvival rates of IVF and SCNT blastocysts were
increased in E-64 treatment groups when compared with the control. On the other hand, we
found that IVF and SCNT blastocysts derived from E-64-treated groups had increased total
cell numbers and decreased apoptotic nuclei. Furthermore, assessment of the expression of
apoptosis-related genes (Bax and Bcl-xL) in bovine IVF and SCNT blastocysts treated with
E-64 by real-time RT-PCR analysis revealed suppressed expression of the pro-apoptotic gene
Bax and stimulated expression of the anti-apoptotic gene Bcl-xL. Taken together, these
finding indicate that addition of E-64 to embryo culture medium may have important
implications for improving developmental competence and preimplantation quality in bovine
IVF and SCNT embryos. 相似文献
8.
Kim SH Yong HC Yoon JH Youn HY Yoshioka N Kano R Hasegawa A 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(10):1139-1140
A 6-month-old male golden retriever was presented with fever, bloody-watery diarrhea and mild cough. Parvovirus and Isospora canis infection was confirmed and successfully treated. Two weeks later, the dog had severe cough and mucopurulent nasal discharge. Aspergillus niger was cultured from endotracheal washings on blood agar at 37 degrees C. Treatment with itraconazole for about 10 weeks resolved the clinical signs. 相似文献
9.
Haejeen Bang Dong Youn Cho Kil-Sun Yoo Moo-Kyoung Yoon Bhimanagouda S. Patil Sunggil Kim 《Euphytica》2011,179(3):439-449
In order to implement reliable marker-assisted selection systems for the restorer-of-fertility locus (Ms) in onions (Allium cepa L.), simple PCR-based codominant markers linked to the Ms locus were developed. Based on the EST probe sequences of previously reported RFLP markers, full-length genomic sequences
of the gene encoding putative oligopeptide transporter (OPT) was obtained by RACE. The first intron contained two 108 and
439-bp indel polymorphisms between the two Ms allele-linked OPT alleles. A simple PCR marker for OPT was developed by designing a primer pair on the flanking regions of
the 108-bp indel which is created by two tandem repeats. The second simple PCR marker was developed from the EST probe encoding
photosystem I subunit O (PsaO). Two 14 and 39-bp tandem repeats were identified from the 5′ upstream sequences of the PsaO-coding
gene, which were isolated by genome walking. Three different compositions of these tandem repeats were identified from diverse
onion germplasm. A primer set binding to the flanking sequence of these polymorphic repeats was used to amplify three different
marker haplotypes. The OPT marker was tightly linked to the Ms locus at a distance of 1.5 cM, but the analysis of the linkage relationship showed little linkage disequilibrium between
the marker and the Ms locus. Even so, these simple PCR markers are valuable tools for the marker-assisted selection of segregating individuals
in onion F1 hybrid breeding programs. 相似文献
10.
Woochul Chang Chang Youn Lee Jun-Hee Park Moon-Seo Park Lee-So Maeng Chee Soon Yoon Min Young Lee Ki-Chul Hwang Yong-An Chung 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(1):69-76
The use of mesenchymal stem cells (MSCs) has emerged as a potential new treatment for myocardial infarction. However, the poor viability of MSCs after transplantation critically limits the efficacy of this new strategy. The expression of microRNA-210 (miR-210) is induced by hypoxia and is important for cell survival under hypoxic conditions. Hypoxia increases the levels of hypoxia inducible factor-1 (HIF-1) protein and miR-210 in human MSCs (hMSCs). miR-210 positively regulates HIF-1α activity. Furthermore, miR-210 expression is also induced by hypoxia through the regulation of HIF-1α. To investigate the effect of miR-210 on hMSC survival under hypoxic conditions, survival rates along with signaling related to cell survival were evaluated in hMSCs over-expressing miR-210 or ones that lacked HIF-1α expression. Elevated miR-210 expression increased survival rates along with Akt and ERK activity in hMSCs with hypoxia. These data demonstrated that a positive feedback loop involving miR-210 and HIF-1α was important for MSC survival under hypoxic conditions. 相似文献