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41.
Shivani M Chidrawar Naeem Khan Y L Tracey Chan Laxman Nayak Paul AH Moss 《Immunity & ageing : I & A》2006,3(1):10-8
Background
Natural killer (NK) cells are cytotoxic lymphocytes that lack CD3 and express variable levels of CD16, CD56 and CD57. In recent years NK cells have been categorised into two major groups based on the level of CD56 expression. This phenotypic classification correlates with functional activity as CD56bright NK cells are the major cytokine producing subset whereas CD56dim NK cells exhibit greater cytotoxic activity. Previous studies have revealed a reduction in total NK cell numbers in association with ageing and this study sought to determine the potential influence of ageing on the number of NK cell subsets within peripheral blood. 相似文献42.
Hurren R Beheshti Zavareh R Dalili S Wood T Rose D Chang H Jamal N Messner H Batey RA Schimmer AD 《Apoptosis : an international journal on programmed cell death》2008,13(6):748-755
Quinolines are a class of chemical compounds with emerging anti-cancer properties. Here, we tested the activity of series
of quinolines and quinoline-like molecules for anti-cancer activity and identified a novel diquinoline, 1-methyl-2-[3-(1-methyl-1,2-dihydroquinolin-2-yliden)prop-1-enyl]quinolinium
iodide (Q2). Q2 induced cell death in leukemia, myeloma, and solid tumor cell lines with LD50s in the low to submicromolar range. Moreover,
Q2 induced cell death in primary acute myeloid leukemia (AML) cells preferentially over normal hematopoietic cells. In a mouse
model of leukemia, Q2 delayed tumor growth. Mechanistically, Q2 induced cell death through caspase independent mechanisms. By electron microscopy, Q2 increased cytoplasmic vacuolization and mitochondrial swelling. Potentially consistent with the induction of autophagic cell
death, Q2 treatment led to a punctate distribution of LC3 and increased MDC staining. Thus, Q2 is a novel quinolinium with preclinical activity in malignancies such as leukemia and myeloma and warrants further investigation. 相似文献
43.
Coregulation of beta-galactoside uptake and hydrolysis by the hyperthermophilic bacterium Thermotoga neapolitana 下载免费PDF全文
Regulation of the beta-galactoside transport system in response to growth substrates in the extremely thermophilic anaerobic bacterium Thermotoga neapolitana was studied with the nonmetabolizable analog methyl-beta-D-thiogalactopyranoside (TMG) as the transport substrate. T. neapolitana cells grown on galactose or lactose accumulated TMG against a concentration gradient in an intracellular free sugar pool that was exchangeable with external galactose or lactose and showed induced levels of beta-galactosidase. Cells grown on glucose, maltose, or galactose plus glucose showed no capacity to accumulate TMG, though these cells carried out active transport of the nonmetabolizable glucose analog 2-deoxy-D-glucose. Glucose neither inhibited TMG uptake nor caused efflux of preaccumulated TMG; rather, glucose promoted TMG uptake by supplying metabolic energy. These data show that beta-D-galactosides are taken up by T. neapolitana via an active transport system that can be induced by galactose or lactose and repressed by glucose but which is not inhibited by glucose. Thus, the phenomenon of catabolite repression is present in T. neapolitana with respect to systems catalyzing both the transport and hydrolysis of beta-D-galactosides, but inducer exclusion and inducer expulsion, mechanisms that regulate permease activity, are not present. Regulation is manifest at the level of synthesis of the beta-galactoside transport system but not in the activity of the system. 相似文献
44.
The core domain of retrotransposon integrase in Hordeum: predicted structure and evolution 总被引:1,自引:0,他引:1
Suoniemi A; Tanskanen J; Pentikainen O; Johnson MS; Schulman AH 《Molecular biology and evolution》1998,15(9):1135-1144
Propagation of long terminal repeat (LTR)-bearing retrotransposons and
retroviruses requires integrase (IN, EC 2.7.7.-), encoded by the
retroelements themselves, which mediates the insertion of cDNA copies back
into the genome. An active retrotransposon family, BARE-1, comprises
approximately 7% of the barley (Hordeum vulgare subsp. vulgare) genome. We
have generated models for the secondary and tertiary structure of BARE-1 IN
and demonstrate their similarity to structures for human immunodeficiency
virus 1 and avian sarcoma virus INs. The IN core domains were compared for
80 clones from 28 Hordeum accessions representative of the diversity of the
genus. Based on the structural model, variations in the predicted, aligned
translations from these clones would have minimal structural and functional
effects on the encoded enzymes. This indicates that Hordeum retrotransposon
IN has been under purifying selection to maintain a structure typical of
retroviral INs. These represent the first such analyses for plant INs.
相似文献
45.
van Hoek AH; van Alen TA; Sprakel VS; Hackstein JH; Vogels GD 《Molecular biology and evolution》1998,15(9):1195-1206
The 18S and 5.8S rDNA genes and the internal transcribed spacers ITS-1 and
ITS-2 of ciliates living in the hindgut of frogs, millipedes, and
cockroaches were analyzed in order to study the evolution of intestinal
protists. All ciliates studied here belong to the genus Nycrotherus.
Phylogenetic analysis revealed that these ciliates from a monophyletic
group that includes the distantly related anaerobic free-living
heterotrichous ciliates Metopus palaeformis and Metopus contortus. The
intestinal ciliates from the different vertebrate and invertebrate hosts
are clearly divergent at the level of their rDNA repeats. This argues for
the antiquity of the associations and a predominantly vertical
transmission. This mode of transmission seems to be controlled primarily by
the behavior of the host. The different degrees of divergence between
ciliates living in different strains of one and the same cockroach species
most likely reflect the different geographical origins of the hosts. In
addition, host switches must have occurred during the evolution of
cockroaches, since identical ciliates were found only in distantly related
hosts. These phenomena prevent the reconstruction of potential cospeciation
events.
相似文献
46.
47.
Valérie Simonneaux AH Ouichou Cheryl Craft Paul Pévet 《Journal of neurochemistry》1994,62(6):2464-2471
Abstract: Neuropeptide Y is colocalized with noradrena-line in sympathetic fibers innervating the rat pineal gland. In this article we present a study of the effects and mechanisms of action of neuropeptide Y on the pineal noradrenergic transmission, the main input leading to the rhythmic secretion of melatonin. At the presynaptic level, neuropeptide Y inhibits by 45%, with an EC50 of 50 n M , the potassium-evoked noradrenaline release from pineal nerve endings. This neuropeptide Y inhibition occurs via the activation of pertussis toxin-sensitive G protein-coupled neuropeptide Y-Y2 receptors and is independent from, but additive to, the α2 -adrenergic inhibition of noradrenaline release. At the postsynaptic level, neuropeptide Y decreases by a maximum of 35%, with an EC50 of 5 n M , the β-adrenergic induction of cyclic AMP elevation via the activation of neuropeptide Y-Y1 receptors. This moderate neuropeptide Y-induced inhibition of cyclic AMP accumulation, however, has no effect on the melatonin secretion induced by a β-adrenergic stimulation. On the contrary, in the presence of 1 m M ascorbic acid, neuropeptide Y potentiates (up to threefold) the melatonin secretion. In conclusion, this study has demonstrated that neuropeptide Y modulates the noradrenergic transmission in the rat pineal gland at both presynaptic and postsynaptic levels, using different receptor subtypes and transduction pathways. 相似文献
48.
Eman A.E. Badr Abd El-Aleem Hassan Abd El-Aleem Samah EL-Ghlban Asmaa AH. Swelm Mahmoud Emara 《Biochemistry and Biophysics Reports》2019
ObjectivesThe prognosis of high-risk patients might be greatly ameliorated using genetic predisposition risk factors. Sympathetic activity and innate immunity related to neuropeptide Y function may be related to dyslipidemia and atherosclerosis. The aim of this study is to detect the correlation between Neuropeptide Y (NPY) SNP rs16147 and its gene expression in chronic kidney disease with and without hypertension.MethodsThis study carried out on 150 subjects who were divided into 3 main groups group (I) 50 CKD patients with hypertension, group (II) 50 CKD patients without hypertension and group (III) 50 healthy individuals. Carotid intima media thickness (CIMT) was measured by Ultrasound. Kidney function test and lipid profile were performed. Genotyping and gene expression of neuropeptide Y (NPY) were performed using real time PCR.ResultsThere was a significant increase in number and percentage of CC genotype and C allele of NPY SNP distribution in CKD patients with and without hypertension when compared to controls. A significant association was found between CC genotype and C allele and the risk of CKD with hypertension with odd ratio 3.26 and 1.77, respectively. There is a significant positive correlation between NPY gene expression level and CIMT among chronic kidney disease patients with highest level of TC, LDLc and CIMT among CC genotype of NPY gene.ConclusionA significant association was found between CC genotype and C allele of NPY at rs16147 with increase NPY gene expression and risk of developing hypertension in CKD. 相似文献
49.
Tahereh Bakhtiari Afshin Ghaderi Sayyed Reza Safaee Nodehi Zahra Aghazadeh Farzaneh Tofighi Zavareh Fahimeh Jafarnezhad-Ansariha Anis Barati Abbas Mirshafiey 《Journal of cellular physiology》2019,234(8):12971-12977
β-d -Mannuronic acid (M2000), a novel non-steroidal anti-inflammatory drug (NSAID) with immunosuppressive properties, has been previously shown to exhibit potential therapeutic effects on autoimmune diseases. Immunosuppression therapy has been a standard approach for myelodysplastic syndrome (MDS) for many years. We evaluated the effect of M2000 on isolated peripheral blood mononuclear cells (PBMCs) from patients with MDS. The PBMCs were isolated from 13 patients with MDS and 13 normal donors. The cells were then treated with low, moderate, and high doses of M2000 and diclofenac as a control group. The level of interleukin (IL)-6, tumor necrosis factor alpha (TNF-α), IL-3, granulocyte colony-stimulating factor (G-CSF) gene expression and the serum level of IL-6 and TNF-α production were evaluated by real-time polymerase chain reaction and enzyme-linked immunosorbent assay methods, respectively. Our findings indicated a significant reduction in the production of IL-6 and TNF-α as inflammatory cytokines. Furthermore, the level of G-CSF gene expression was significantly increased. In conclusion, M2000, a newly designed NSAID, has a remarkable effect on isolated PBMC in patients with MDS, which might bring a potential hope for its oral administrations in these patients. 相似文献
50.
Elham Motallebzadeh Abolfazl Azami Tameh Sayyed Alireza Talaei Zavareh Bagher Farhood Akbar Aliasgharzedeh Mehran Mohseni 《Journal of cellular physiology》2020,235(11):8791-8798
This study aimed to determine the effects of melatonin on irradiation-induced apoptosis and oxidative stress in the brainstem region of Wistar rats. Therefore, the animals underwent whole-brain X-radiation with a single dose of 25 Gy in the presence or absence of melatonin pretreatment at a concentration of 100 mg/kg BW. The rats were allocated into four groups (10 rats in each group): namely, vehicle control (VC), 100 mg/kg of melatonin alone (MLT), irradiation-only (RAD), and irradiation plus 100 mg/kg of melatonin (RAM). An hour before irradiation, the animals received intraperitoneal (IP) melatonin and then were killed after 6 hr, followed by measurement of nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and total antioxidant capacity (TAC) in the brainstem region. Furthermore, the western blot analysis technique was performed to assess the caspase-3 expression level. Results showed significantly higher MDA and NO levels in the brainstem tissues for the RAD group when compared with the VC group (p < .001). Moreover, the irradiated rats exhibited a significant decrease in the levels of CAT, SOD, GPx, and TAC (p < .01, p < .001, p < .001, and p < .001, respectively) in comparison to the VC group. The results of apoptosis assessment revealed that the expression level of caspase-3 significantly rose in the RAD group in comparison with the VC group (p < .001). Pretreatment with melatonin ameliorated the radiation-induced adverse effects by decreasing the MDA and NO levels (p < .001) and increasing the antioxidant enzyme activities (p < .001). Consequently, the caspase-3 protein expression level in the RAM group showed a significant reduction in comparison with the RAD group (p < .001). In conclusion, melatonin approximately showed a capacity for neuroprotective activity in managing irradiation-induced oxidative stress and apoptosis in the brainstem of rats; however, the use of melatonin as a neuroprotective agent in humans requires further study, particularly clinical trials. 相似文献