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61.
Nooshin Babapour Mehrane Mehramiz Azam Rastgar Moghadam Negin Behboodi Zohre Yousefi Mona Maftouh Sahar Talebian Majid Khazaei Amirhosein Jafarian Noorieh Sharifi-Sistani Amir Avan Malihe Hasanzadeh 《Journal of cellular biochemistry》2019,120(4):5444-5448
Tumor necrosis factor a (TNFa) is an inflammatory cytokine that plays a crucial role in the immune response and the progression of cervical lesions. There is a growing body of data evaluating the value of a genetic variant in the TNFa gene with the risk of developing cervical cancer. The aim of this study was to explore the association of a variant, TNF-308 G>A, residing in the TNFa gene with cervical cancer. A total of 91 women with cervical cancer and 161 women as the control group were recruited. DNA was extracted, and Taqman®-probes-based assay was used for genotyping. Our results showed that the minor allele frequency was 0.3 in total population, and the frequency of minor allele A was more in the case group compared with the control. The regression models in different genetic models also revealed that the allele A is a potential risk factor for the development of cervical cancer. In particular, in the dominant model, patients with AG and AA genotypes had a higher risk of developing cervical cancer with odds ratio (OR) of 2.75 (95% confidence interval [CI]: 1.57-4.83, <0.001) and OR of 7.27 (95%CI: 2.5-20.8, <0.001), compared with the GG genotype. Moreover, a similar outcome was obtained for smear test results. Our study demonstrated that TNF-308 G>A located on TNF-a was associated with the risk of cervical cancer, supporting further studies in a larger population and multicenter setting to show the value of emerging markers as risk stratification biomarkers in cervical cancer. 相似文献
62.
El-Naggar MY Akeila MA Turk HA El-Ebady AA Sahaly MZ 《The Journal of General and Applied Microbiology》2001,47(2):63-73
Three disinfectants commonly used in poultry farms (formalin, TH4+, and Virkon-S) were chosen for the present study. The effect of disinfectant concentration and the duration of exposure to these disinfectants on the survival of Escherichia coli serotypes (O114:K-, O86, O55:K39, and O86:K60) were investigated. Formalin (0.6%), TH4+ (0.06%), and Virkon (0.5%) all killed the four serotypes within 5 min of exposure. As the disinfectant concentration decreases, the length of exposure time to kill serotype increases. At 0.03%, 0.007%, and 0.03% of formalin, TH4+ and Virkon-S concentrations failed to kill the four E. coli serotypes within 360 min, respectively. An improvement of the inhibitory effect of these disinfectants occurred when added together with the inoculum instead of an established population. The influence of formalin, TH4+, and Virkon-S on the cell morphology of E. coli O55:K39 was investigated by using transmission electron microscopy. Formalin-treated cells exhibited normal cell morphology, with the exception that the treated cell was less fimbriated, and more destruction of pili increased when formalin concentrations were doubled. Cells treated with TH4+ (0.03%) showed destruction of the cell wall and cell surface membrane after 5 min. Cell filamentation occurred at 0.015% and increased with the increase of exposure time to this drug. Spheroplasts were observed only when cells were treated with 0.125% Virkon-S for 60 min, and cell lysis started to occur when 0.25% Virkon-S was applied for 15 min. Scanning electron microscope study revealed that Virkon-S at 0.03% and TH4+ at 0.007% completely prevented the adherence of E. coli O55:K39 serotype to chicken tracheal organ, whereas formalin (0.03%) disinfection minimized the adherence of E. coli cells to tracheal explants after 360 min of incubation. 相似文献
63.
A Fusarium species with a micro morphology similar to F. poae and a metabolite profile resembling that of F. sporotrichioides has been identified. Like typical F. poae, the microconidia have a globose to pyriform shape, but the powdery appearance, especially on Czapek-Dox Iprodione Dichloran
agar (CZID), less aerial mycelium and the lack of fruity odour on Potato Sucrose Agar (PSA) make it different from F. poae. The lack of macroconidia, polyphialides and chlamydospores differentiates it from F. sporotrichioides. All 18 isolates investigated, 15 Norwegian, two Austrian and one Dutch, produced T-2 toxin (25–400 μg/g) on PSA or Yeast
Extract Sucrose agar (YES). In addition, neosolaniol, iso-neosolaniol, HT-2 toxin, 4- and 15-acetyl T-2 tetraol, T-2 triol
and T-2 tetraol and4,15-diacetoxyscirpenol were formed in variable amounts. Neither nivalenol, 4- or 15-acetylnivalenolor
4,15-diacetylnivalenol were detected in any of the cultures, while these toxins were produced at least in small amounts by
all the 12 typical F. poae isolates studied. The question of whether this Fusarium should be classified as F. poae or F. sporotrichioides or a separate taxon should be addressed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
64.
Application of discriminant analysis and quantitative cytologic examination to gastric lesions 总被引:2,自引:0,他引:2
Karakitsos P Megalopoulou TM Pouliakis A Tzivras M Archimandritis A Kyroudes A 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2004,26(6):314-322
OBJECTIVE: To investigate of the potential value of morphometry and discriminant analysis for the classification of benign and malignant gastric cells and lesions. STUDY DESIGN: The data set consisted of 13,300 cells from 120 cases composed of 30 cases of cancer, 26 cases of gastritis and 64 cases of ulcer according to the final histologic diagnosis. The cytologic diagnosis was divided into 5 categories (gastritis, ulcer, inflammatory dysplasia, cancer and true dysplasia). Classification was attempted at 2 levels: the cell level to classify individual cells and the case level to classify individual cases. For the cellular classification the measured cells from 50% of available cases were selected as a training set to construct a model. The cells from the remaining cases were used as a test set to validate the model. Similarly for case classification, the same 50% of cases that were used for cell classification were used as a training set and the remaining cases as a test set. Images of routinely processed gastric smears stained by the Papanicolaou technique were analyzed by a customized image analysis system. RESULTS: Application of discriminant analysis on the test set gave correct classification of 98.4% of benign cells and 67.1% of malignant cells. On case classification, 100% accuracy was achieved for benign and malignant cases, both for the training and test sets. CONCLUSION: The application of discriminant analysis described in this paper could produce significant classification results at the cellular and individual case level. 相似文献
65.
A revised checklist of planktonic diatoms and dinoflagellates from Helgoland (North Sea,German Bight) 总被引:1,自引:0,他引:1
A checklist based on net samples taken twice weekly from 2001 until May 2003 is presented. Identification is based on observations under direct light microscopy and after taking some organisms in culture. The checklist includes 227 taxa observed at the Helgoland Reede sampling station. One hundred and thirty-two species of diatoms from 53 genera and 95 species of dinoflagellates from 35 genera have been recorded from net samples and cultures. Thirty-five diatom and 28 dinoflagellate taxa were documented in the Helgoland phytoplankton for the first time. The list does not claim to be complete, but provides an updated list of the taxa found at Helgoland and, for convenience, also includes data published for different adjacent areas.Communicated by K. Wiltshire 相似文献
66.
67.
QSAR calculations of (13)C NMR chemical shifts (ppm, TMS=0) on carbinol carbon atoms have been attempted using a large set of distance based topological indices: Wiener (W)-, Szeged (Sz)-, PI (Padmakar-Ivan) and Connectivity ((m)chi, (m)chi(v)) indices. The regression analysis has shown that excellent results are obtained in multiparametric regression. The predictive power of the proposed models are discussed using cross-validated parameters. 相似文献
68.
Quantitative evaluation by minisequencing and microarrays reveals accurate multiplexed SNP genotyping of whole genome amplified DNA 总被引:11,自引:3,他引:8 下载免费PDF全文
Whole genome amplification (WGA) procedures such as primer extension preamplification (PEP) or multiple displacement amplification (MDA) have the potential to provide an unlimited source of DNA for large-scale genetic studies. We have performed a quantitative evaluation of PEP and MDA for genotyping single nucleotide polymorphisms (SNPs) using multiplex, four-color fluorescent minisequencing in a microarray format. Forty-five SNPs were genotyped and the WGA methods were evaluated with respect to genotyping success, signal-to-noise ratios, power of genotype discrimination, yield and imbalanced amplification of alleles in the MDA product. Both PEP and MDA products provided genotyping results with a high concordance to genomic DNA. For PEP products the power of genotype discrimination was lower than for MDA due to a 2-fold lower signal-to-noise ratio. MDA products were indistinguishable from genomic DNA in all aspects studied. To obtain faithful representation of the SNP alleles at least 0.3 ng DNA should be used per MDA reaction. We conclude that the use of WGA, and MDA in particular, is a highly promising procedure for producing DNA in sufficient amounts even for genome wide SNP mapping studies. 相似文献
69.
70.
Acute and chronic leptin treatment mediate contrasting effects on signaling,glucose uptake,and GLUT4 translocation in L6-GLUT4myc myotubes 总被引:3,自引:0,他引:3
We have previously shown that in L6-GLUT4myc rat skeletal muscle cells, acute treatment with leptin reduced insulin-stimulated glucose uptake without altering insulin-stimulated GLUT4 translocation. In contrast, we show here that the ability of leptin to increase phosphorylation of its receptor and to reduce insulin-stimulated glucose uptake was lost in cells that were continuously exposed to leptin for 24 h. This desensitization correlated with an increase in expression of suppressor of cytokine signaling-3 (SOCS-3). Time course analysis demonstrated that the transition from acute to chronic effects of leptin occurs after 2 h. The desensitization of leptin action at 24 h was not reversed by 30 min washout period prior to re-exposing cells to leptin. However, despite insulin-stimulated glucose uptake being unaffected upon 24 h preincubation with leptin, a small but significant decrease (37%) in insulin-stimulated GLUT4 translocation and phosphorylation of Akt on T308 was detected. Insulin-stimulated phosphorylation of Akt on S473 or of p38 MAPK were unaffected. These results suggest that the chronic leptin treatment leads to desensitization of leptin signaling yet can simultaneously decrease the ability of insulin to phosphorylate Akt on T308 and translocate GLUT4. However, this does not manifest as a reduction in total glucose uptake into L6 myotubes. 相似文献