排序方式: 共有340条查询结果,搜索用时 93 毫秒
41.
Mehdipour P Kheirollahi M Mehrazin M Kamalian N Atri M 《Cell biology international》2011,35(9):915-925
It was previously reported that tumour samples had shorter telomeres than the surrounding normal tissue. Hereby, the initial sign of correlation between malignant tissue and telomere behaviour could be noticed. Bridging knowledge between germ and somatic cells could facilitate understanding cellular evolution. The aim of our investigation was to provide evidence for the evolutionary hypothesis of TL (telomere length) in primary BC (breast cancer) and BTs (brain tumours), which might be applied as a prognostic and/or predictive marker. DNA extraction from the frozen tissues was performed using high pure PCR template preparation kit. Standard protocol of Telo TTAGGG Telomere Length Assay kit, a non‐radioactive chemiluminescent assay, was used. The protein expression in extracted cells was analysed by immunofluorescence. We also detected telomerase activity. The G/T (genomic/tumour ratio) for TL in two groups of patients affected with primary BC and primary BT revealed significant differences in both BC patients (P=0.025) and in BTs (P=0.001). The pattern of telomere signals by Q‐FISH (quantitative fluorescent in situ hybridization) show that in all samples, except one, SI (signal intensity) has been significantly decreased in tissue related to blood, either in BC patients or in patients with BTs (0.041≥P≥0.001). However, the data achieved by Q‐FISH support the results of Southern blot. These data reflect a significant diversity either in BC or in BT patients, providing evidence for the evolutionary hypothesis of TL in cancer development and progression. 相似文献
42.
Sonboli A Eftekhar F Yousefzadi M Kanani MR 《Zeitschrift für Naturforschung. C, Journal of biosciences》2005,60(1-2):30-34
The chemical composition of the essential oils obtained from two samples (GP1 and GP2) of Grammosciadium platycarpum Boiss. was analyzed by GC and GC-MS. The analysis of the oils resulted in the identification of twenty-two constituents. Linalool (79.0%-GP1, 81.8%-GP2) and limonene (10.0%, 5.8%) were found to be the major components, respectively. The in vitro antibacterial activities of these oils and their main compounds against seven Gram-positive and Gram-negative bacteria were investigated. The results exhibited that the total oils and their major components possess strong to moderate activities against all the tested bacteria except for Pseudomonas aeruginosa. 相似文献
43.
Animal phyla that require macro-scale fluid transport for functioning have repeatedly and often independently converged on the use of jet flows. During flow initiation these jets form fluid vortex rings, which facilitate mass transfer by stationary pumps (e.g. cardiac chambers) and momentum transfer by mobile systems (e.g. jet-propelled swimmers). Previous research has shown that vortex rings generated in the laboratory can be optimized for efficiency or thrust, based on the jet length-to-diameter ratio (L/D), with peak performance occurring at 3.5相似文献
44.
Asidi AN N'Guessan R Koffi AA Curtis CF Hougard JM Chandre F Corbel V Darriet F Zaim M Rowland MW 《Malaria journal》2005,4(1):25-9
Background
Pyrethroid resistant mosquitoes are becoming increasingly common in parts of Africa. It is important to identify alternative insecticides which, if necessary, could be used to replace or supplement the pyrethroids for use on treated nets. Certain compounds of an earlier generation of insecticides, the organophosphates may have potential as net treatments.Methods
Comparative studies of chlorpyrifos-methyl (CM), an organophosphate with low mammalian toxicity, and lambdacyhalothrin (L), a pyrethroid, were conducted in experimental huts in Côte d'Ivoire, West Africa. Anopheles gambiae and Culex quinquefasciatus mosquitoes from the area are resistant to pyrethroids and organophosphates (kdr and insensitive acetylcholinesterase Ace.1 R ). Several treatments and application rates on intact or holed nets were evaluated, including single treatments, mixtures, and differential wall/ceiling treatments.Results and Conclusion
All of the treatments were effective in reducing blood feeding from sleepers under the nets and in killing both species of mosquito, despite the presence of the kdr and Ace.1 R genes at high frequency. In most cases, the effects of the various treatments did not differ significantly. Five washes of the nets in soap solution did not reduce the impact of the insecticides on A. gambiae mortality, but did lead to an increase in blood feeding. The three combinations performed no differently from the single insecticide treatments, but the low dose mixture performed encouragingly well indicating that such combinations might be used for controlling insecticide resistant mosquitoes. Mortality of mosquitoes that carried both Ace.1 R and Ace.1 S genes did not differ significantly from mosquitoes that carried only Ace.1 S genes on any of the treated nets, indicating that the Ace.1 R allele does not confer effective resistance to chlorpyrifos-methyl under the realistic conditions of an experimental hut. 相似文献45.
Community structure and function in a H2-based membrane biofilm reactor capable of bioreduction of selenate and chromate 总被引:1,自引:0,他引:1
Chung J Ryu H Abbaszadegan M Rittmann BE 《Applied microbiology and biotechnology》2006,72(6):1330-1339
Two different H2-based, denitrifying membrane-biofilm reactors (MBfRs) initially reduced Se(VI) or Cr(VI) stably to Se0 or Cr(III). When the oxidized contaminants in the influent were switched, each new oxidized contaminant was reduced immediately, and its reduction soon was approximately the same or greater than it had been in its original MBfR. The precipitation of reduced selenium and chromium in the biofilm was verified by scanning electron microscopy and energy dispersive X-ray analysis. These results on selenate and chromate reduction are consistent with the interpretation that the H2-based biofilm community had a high level of functional diversity. The communities’ structures were assessed by cloning analysis. Dechloromonas spp., a known perchlorate-reducing bacteria, dominated the clones from both reactors during selenate and chromate reductions, which suggests that it may have functional diversity capable of reducing selenate and chromate as secondary and dissimilatory acceptors. 相似文献
46.
Nakhjavani M Morteza A Asgarani F Khalilzadeh O Ghazizadeh Z Bathaie SZ Esteghamati A 《Gene》2012,498(1):107-111
Background
Experimental evidence suggests that heat shock proteins (HSP) and asymmetric dimethylarginine (ADMA) are induced in the state of chronic inflammation and stress conditions. They are both inhibitors of nitric oxide synthase (NOS). The aim of this study was to evaluate the correlation between ADMA and HSP70, in patients with type 2 diabetes with respect to serum levels of C reactive protein (CRP).Methods
We quantified serum HSP70, ADMA and CRP in 80 newly-diagnosed patients with type 2 diabetes plus 80 age-, sex and BMI-matched healthy controls. The patients and controls were also stratified into groups of high and low CRP levels (cut-point: 2.5 mg/ml).Results
Patients with type 2 diabetes had significantly higher serum HSP70 (0.52 [0.51–0.66] vs. 0.27 [0.26–0.36], p < 0.001), ADMA (0.86 [0.81–0.92] vs. 0.72 [0.71–0.85], p < 0.05) and CRP (2.9 [1.7–3.4] vs. 1.6[1.2–2.3], p < 0.05) compared with healthy controls. Serum HSP70 and ADMA levels were significantly correlated in patients with high CRP levels (r = 0.89, p < 0.01), whereas there were no correlation in patients with low CRP (r = − 0.37, p = 0.07) and controls. This correlation was significant (r = 0.77, p < 0.001) in patients with high CRP and also in patients with low CRP levels (r = − 0.51, p < 0.05), after multiple adjustments for LDL and HDL levels.Discussion
We showed that, in a state of high inflammation; serum levels of ADMA parallel the HSP70 levels. However in low inflammation, they are negatively correlated. The duality in HSP70 and ADMA correlation may be related to the duality of NOS function in low and high CRP levels. 相似文献47.
Taati M Moghadasi M Dezfoulian O Asadian P Kheradmand A Abbasi M Zendehdel M 《Journal of physiology and biochemistry》2012,68(1):91-97
Ghrelin, the endogenous ligand for growth hormone secretagogue receptor, has been reported to prevent ischemia/reperfusion
(I/R) injury in various tissues by its antioxidant activity. Therefore, this study was aimed to investigate the effect of
ghrelin on sperm quality and antioxidant enzyme activity in a rat testicular ischemia/reperfusion injury model. Forty-two
male Wistar rats were divided into groups control, I/R, and I/R plus ghrelin. The right testes were rotated 720° for 1 h and
were allowed to reperfuse for 4 h and 30 days thereafter. Ghrelin (40 nmol/kg IP) or vehicle (physiological saline) was administrated
15 min before reperfusion. After 4 h of reperfusion, a right orchiectomy was performed to measure the biochemical parameters.
In addition, the sperm was collected from the epididymis after 30 days of reperfusion, and sperm characteristics were examined.
The malondialdehyde levels of the testis tissues were significantly increased, but a statistically significant decrease was
found in the superoxide dismutase, glutathione peroxidase, and catalase activities in the I/R group as compared with the control,
indicating I/R injury. The sperm evaluation showed a significant reduction in all characteristics resulted from I/R compared
with the control. In the ghrelin-treated group, the malondialdehyde values were significantly lowered, and only enzyme activity
of glutathione peroxidase showed significant increases compared with the I/R group. Ghrelin significantly enhanced sperm motility,
movement, and concentration but did not prevent I/R-induced reduction in membrane integrity in the testes of rats compared
to the I/R group. Our results suggest that ghrelin treatment has a protective role on IR-induced testicular injury, and this
effect may be due to its antioxidant properties. 相似文献
48.
Using first principle calculations, we investigated cation-π interactions between alkali cations (Li(+), Na(+), and K(+)) and pristine C(24) or doped fullerenes of BC(23), and NC(23). The most suitable adsorption site is found to be atop the center of a six-membered ring of the exterior surface of C(24) molecule. Interaction energies of these cations decreased in the order: Li(+)?>?Na(+)?>?K(+), with values of -31.82, -22.36, and -15.68 kcal mol(-1), respectively. It was shown that the interaction energies are increased and decreased by impurity doping of B and N atoms in adjacent wall of adsorption site, depending on electron donating or receptivity of the doping atoms. 相似文献
49.
Fooladi AA Sattari M Hassan ZM Mahdavi M Azizi T Horii A 《Biotechnology letters》2008,30(12):2061-2059
The bacterial superantigen staphylococcal enterotoxin B (SEB) is a potent inducer of cytotoxic T-cell activity and cytokine
production in vivo. We investigated the possibility of the therapeutic application of SEB in patients with fibrosarcoma. The
anti-tumor effect of SEB in mice with inoculated fibrosarcoma (WEHI-164) was examined by intravenous (IV) and intratumoral
(IT) injection and the sizes of the inoculated tumors, IFN-γ production, and CD4+/CD8+ T cell infiltration were determined.
The inoculated tumors were also examined histologically. In the mice in the IV-injected group, a significant reduction (P < 0.02) of tumor size was observed in comparison with mice in the IT-injected and control groups. Furthermore, the mice in
the IV-injected group showed significantly higher levels of IFN-γ (P < 0.009) and CD4+/CD8+ T cell infiltration when compared with the other groups (P < 0.02). A significantly higher frequency of necrosis in tumor tissues was also observed in mice in the IV-injected group
(P < 0.05). Our present findings suggest that tumor cell death is caused by increased cytotoxic T-cell activity and cytokine
levels in response to the IV injection of SEB and that SEB may be a good option for use as a novel therapy in patients with
fibrosarcoma.
An erratum to this article can be found at 相似文献
50.
Nasser Hashemi Goradel Siamak Heidarzadeh Samira Jahangiri Bagher Farhood Keywan Mortezaee Neda Khanlarkhani Babak Negahdari 《Journal of cellular physiology》2019,234(3):2337-2344
Colorectal cancer (CRC) is the third most prevalent cancer in the world. There are many risk factors involved in CRC. According to recent findings, the tumor microenvironment and feces samples of patients with CRC are enriched by Fusobacterium nucleatum. Thus, F. nucleatum is proposed as one of the risk factors in the initiation and progression of CRC. The most important mechanisms of Fusobacterium nucleatum involved in CRC carcinogenesis are immune modulation (such as increasing myeloid-derived suppressor cells and inhibitory receptors of natural killer cells), virulence factors (such as FadA and Fap2), microRNAs (such as miR-21), and bacteria metabolism. The aim of this review was to evaluate the mechanisms underlying the action of F. nucleatum in CRC. 相似文献