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991.
Do Bich Hang Nguyen Thi Phuong Thao Ho Nguyen Quynh Chi Le Thanh Long Hoang Nghia Son Doan Chinh Chung 《Molecular biology reports》2020,47(5):3675-3689
Molecular Biology Reports - Malignant melanoma is a very aggressive and serious type of cutaneous cancer. Previous studies indicated the anti-cancer activity of aqueous extract of Moringa oleifera... 相似文献
992.
Vo Minh Son Chin-Chyuan Chang Mi-Chen Wu Yuan-Kuang Guu Chiu-Hsia Chiu Winton Cheng 《Fish & shellfish immunology》2009,26(5):691-698
The percent weight gain (PWG) and feed efficiency (FE) of Epinephelus coioides were calculated, and the lactobacilli and total microbiota in the posterior intestines, and non-specific immune parameters of grouper, and its susceptibility to Streptococcus sp. and an iridovirus were determined when the fish were fed diets containing Lactobacillus plantarum at 0 (control), 106, 108, or 1010 colony-forming units (cfu) kg?1 for 4 weeks. Results showed that grouper fed a diet containing L. plantarum at the levels of 106, 108, and 1010 cfu kg?1 had significantly increased PGW and FE especially at 108 cfu kg?1 group which were 404.6% and 1.26, respectively. L. plantarum significantly increased in the fish posterior intestines during the L. plantarum feeding period, but decreased rapidly from the intestine within 1 week after changing to the control diet (without L. plantarum). Fish fed a diet containing L. plantarum at 106 and 108 cfu kg?1 had significantly higher survival rates than those fed the control diet after challenge with Streptococcus sp., as well as those fed 108 cfu kg?1 after challenge with an iridovirus, causing increases in the survival rates of 23.3%, 20.0%, and 36.7%, respectively, compared to the control group. The alternative complement activity (ACH50) level of fish fed diets containing L. plantarum after 4 weeks was significantly higher than that of fish fed the control diet, and that of the 108 cfu kg?1 group was significantly higher than those of the 106 and 1010 cfu kg?1 groups, which increased by 83.4% compared to the control group. The lysozyme activity and glutathione peroxidase (GPx) activity of fish fed the L. plantarum-containing diets at 108 and 1010 cfu kg?1 significantly increased compared to those fed the 106 cfu kg?1 L. plantarum diet and control diet, and had increased by 76.3% and 136.6%, and 57.1% and 113.3%, respectively, compared to those fed the control diet. The phagocytic activity (PA), phagocytic index (PI), and respiratory bursts of head kidney leucocytes of fish fed 106, 108, and 1010 cfu kg?1 L. plantarum diets were significantly higher than those of fish fed the control diet after 4 weeks of feeding, and increased 2.2-, 2.2-, and 2.3-fold; 1.8-, 1.8-, and 2.0-fold; and 1.4-, 1.4-, and 1.4-fold, respectively, compared to the control group. We therefore recommend dietary L. plantarum administration at 108 cfu kg?1 to promote growth and enhance immunity and resistance against Streptococcus sp. and an iridovirus of E. coioides. 相似文献
993.
994.
X. Nassif † J. C. Mathison E. Wolfson J. A. Koziol R. J. Ulevitch M. Son † 《Molecular microbiology》1992,6(5):591-597
Tumour necrosis factor alpha (TNF-alpha) has been shown to be the principal mediator of Gram-negative bacterial endotoxin-induced shock. Nevertheless, evidence suggests that TNF-alpha plays a beneficial role in controlling bacterial infections when multiplication of the microorganism is required to kill the host. Using an infant rat model of Neisseria meningitidis infection, we found that blood TNF-alpha concentration reaches a peak three hours after intraperitoneal injection of 3 x 10(6) bacteria. Thereafter, the level of TNF-alpha decreased and was undetectable six to eight hours after infection. A correlation was observed between the magnitude of initial TNF-alpha response and a fatal outcome. Pretreatment of the animals with polyclonal anti-TNF antiserum significantly reduced mortality relative to animals pretreated with control serum. However, pretreatment of animals with anti-TNF antibody did not alter the bacterial invasion of the cerebrospinal fluid. Injection of heat-killed bacteria did not cause death and induced lower TNF-alpha levels than the same number of live bacteria. This excludes the possibility that the role of TNF-alpha is to mediate a shock induced by the endotoxin component of the bacterial inoculum. These results indicate that TNF-alpha has a deleterious effect in this model of bacteraemia. Identification of the critical factors that determine the action of TNF-alpha during lethal bacteraemia will lead to a better understanding of these diseases and the development of appropriate therapeutic intervention. 相似文献
995.
Lee M Lee Y Cho HJ Hong J Kwon SJ Park CG Lee HY Son JW Kang J 《Molecular biology reports》2011,38(8):5211-5217
Lung cancer is the most common cause of cancer death worldwide. Smoking is known as the strongest single factor in the development
of lung cancer. However, there are inherited genetic factors that cause different responses to cigarette smoking exposure
among individuals. We tried to identify these differences in heavy smokers by examining copy number variations (CNVs) between
lung cancer patients and healthy controls. Analysis by array comparative genomic hybridization which was tested with 20-person
training set (10 lung cancer patients, 10 healthy controls) showed 26 significant (adjusted P < 0.05) clones with either copy number gains or losses. Three genes, KCTD11, FGF11, and PTPRH on chromosomal regions 17p13.1 (KCTD11 and FGF11) and 19q13.42 (PTPRH), were selected (adjusted P < 0.001) and tested by real-time quantitative PCR with 34 healthy controls and 54 lung cancer patients. KCTD11 on the chromosomal region 17p13.1 showed significant high odds ratio (OR = 16.0) in heavy smokers, implying that this is
a susceptibility region for lung cancer in this group. Therefore, CNVs of 17p13.1 is a promising candidate to identify individuals
with a high genetic risk for the development of lung cancer. 相似文献
996.
Voltage-dependent anion channels (VDACs) are pore forming proteins predominantly found in the outer mitochondrial membrane and are thought to transport Ca(2+). In this study, we have investigated the possible role of type 2 VDAC (VDAC2) in cardiac Ca(2+) signaling and Ca(2+) sparks using a lentiviral knock-down (KD) technique and two-dimensional confocal Ca(2+) imaging in immortalized autorhythmic adult atrial cells, HL-1. We confirmed high expression of VDAC2 protein in ventricular, atrial, and HL-1 cells using Western blot analysis. Infection of HL-1 cells with VDAC2-targeting lentivirus reduced the level of VDAC2 protein to ~10%. Comparisons of autorhythmic Ca(2+) transients between wild-type (WT) and VDAC2 KD cells showed no significant change in the magnitude, decay, and beating rate of the Ca(2+) transients. Caffeine (10mM)-induced Ca(2+) release, which indicates sarcoplasmic reticulum (SR) Ca(2+) content, was not altered by VDAC2 KD. Interestingly, however, the intensity, width, and duration of the individual Ca(2+) sparks were significantly increased by VDAC2 KD in resting conditions, with no change in the frequency of sparks. VDAC2 KD significantly delayed mitochondrial Ca(2+) uptake during artificial Ca(2+) pulses in permeabilized HL-1 cells. These results suggest that VDAC2 may facilitate mitochondrial Ca(2+) uptake and restrict Ca(2+) spark expansion without regulating activations of sparks under resting conditions, thereby providing evidence on the functional role of VDAC2 in cardiac local Ca(2+) signaling. 相似文献
997.
Kim H Son HJ Ha SC Kim EA Kim TU Choi SY Ahn JY Cho SW 《Cellular and molecular neurobiology》2011,31(7):979-984
Oxidative stress, glutamate excitotoxicity, and inflammation are the important pathological mechanisms in neurodegenerative
diseases. Recently, we reported that 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride protects rat glial cells against
glutamate-induced excitotoxicity. In this study, we report the effects of 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride
on primary cultured cortical astrocytes after exposure to hydrogen peroxide (H2O2). Pretreatment of cells with 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride prior to H2O2 exposure attenuated the H2O2-induced reductions in cell survival and superoxide dismutase, catalase, glutathione, and glutathione peroxidase activities.
It also reduced H2O2-induced increases in reactive oxygen species levels, malondialdehyde content, and production of nitric oxide. These effects
were all concentration-dependent. Our results suggest that 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride protects
against oxidative stress. 相似文献
998.
Kim J Choi JN Kang D Son GH Kim YS Choi HK Kwon DY Lee CH 《Bioscience, biotechnology, and biochemistry》2011,75(4):732-739
Liquid chromatography mass spectrometry and multivariate analysis were employed to investigate the correlation between fermentation time-dependent metabolite changes in cheonggukjang, a traditional fermented soybean product, and changes in its antioxidant activity over 72 h. The metabolite patterns were clearly distinguished not by strains but by fermentation time, into patterns I (0-12 h), II (12-24 h), and III (24-72 h), which appeared as distinct clusters on principal component analysis. The compounds that significantly contributed to patterns I, II, and III were soyasaponins, isoflavonoid derivatives, and isoflavonoid aglycons respectively. Partial least square analysis for metabolite to antioxidant effects showed correlations between the ferric reducing/antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay during 24-36 h, and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) test and total phenol content (TPC) during 36-72 h. Compared with the strong negative correlations of glucosylated-isoflavonoids with DPPH, ABTS and TPC during fermentation, the isoflavonoid aglycon displayed strong positive correlations with these compounds during fermentation. 相似文献
999.
Tasaki J Shibata N Nishimura O Itomi K Tabata Y Son F Suzuki N Araki R Abe M Agata K Umesono Y 《Development (Cambridge, England)》2011,138(12):2417-2427
The robust regenerative ability of planarians depends on a population of somatic stem cells called neoblasts, which are the only mitotic cells in adults and are responsible for blastema formation after amputation. The molecular mechanism underlying neoblast differentiation associated with blastema formation remains unknown. Here, using the planarian Dugesia japonica we found that DjmkpA, a planarian mitogen-activated protein kinase (MAPK) phosphatase-related gene, was specifically expressed in blastema cells in response to increased extracellular signal-related kinase (ERK) activity. Pharmacological and genetic [RNA interference (RNAi)] approaches provided evidence that ERK activity was required for blastema cells to exit the proliferative state and undergo differentiation. By contrast, DjmkpA RNAi induced an increased level of ERK activity and rescued the differentiation defect of blastema cells caused by pharmacological reduction of ERK activity. These observations suggest that ERK signaling plays an instructive role in the cell fate decisions of blastema cells regarding whether to differentiate or not, by inducing DjmkpA as a negative regulator of ERK signaling during planarian regeneration. 相似文献
1000.
Kim IH Kim BS Lee KS Kim IJ Son JS Kim KS 《Journal of microbiology and biotechnology》2011,21(12):1228-1235
We compared the gene expression among four clinical and five environmental V. vulnificus isolates, using a cDNA microarray containing 131 genes possibly associated with pathogenicity, transport, signal transduction, and gene regulations in the pathogen. cDNAs from total RNAs of these isolates were hybridized into the cDNA microarray using the cDNA of the wild-type strain MO6/24-O as a reference. We focused on selecting differentially expressed (DE) genes between clinical and environmental isolates using a modified t-statistic. We could detect two statistically significant DE genes between virulent isolates and less-virulent isolates with a marginal statistical significance (pvalue of 0.008). These were genes putatively encoding pilin and adenlyate cylase. Real time-PCR confirmed that these two selected genes transcribed in significantly higher levels in virulent isolates than in less-virulent isolates. Mutants with lesions in the gene encoding pilin showed significantly higher LD50 values than that of wild type. 相似文献