874 resultados para Sense and anti-sense gene cold tolerance
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Recently, we reported a functional interaction between miR-21 and its identified chemokine target CCL20 in colorectal cancer (CRC) cell lines. Here, we investigated whether such functional interactions are permitted at the cellular level which would require an inverse correlation of expression and also co-expression of miR-21 and CCL20 in the same cell. Expression profiling was performed using qPCR, and ELISA, in situ hybridization and immunohistochemistry were applied for the presentation of their cellular localization. We demonstrated that miR-21 as well as CCL20 were both significantly upregulated in CRC tissues; thus, showing no antidromic expression pattern. This provided an initial clue that miR-21 and CCL20 may not be expressed in the same cell. In addition, we located miR-21 expression at the cellular level predominantly in stromal cells such as tumor-associated fibroblasts and to a minor degree in immune cells such as macrophages and lymphocytes. Likewise, CCL20 expression was primarily detected in tumor-infiltrating immune cells. Thus, investigating the cellular localization of miR-21 and its target CCL20 revealed that both molecules are expressed predominantly in the microenvironment of CRC tumors.
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OBJECTIVE: Because studies suggest that ultraviolet (UV) radiation modulates the myositis phenotype and Mi-2 autoantigen expression, we conducted a retrospective investigation to determine whether UV radiation may influence the relative prevalence of dermatomyositis and anti-Mi-2 autoantibodies in the US. METHODS: We assessed the relationship between surface UV radiation intensity in the state of residence at the time of onset with the relative prevalence of dermatomyositis and myositis autoantibodies in 380 patients with myositis from referral centers in the US. Myositis autoantibodies were detected by validated immunoprecipitation assays. Surface UV radiation intensity was estimated from UV Index data collected by the US National Weather Service. RESULTS: UV radiation intensity was associated with the relative proportion of patients with dermatomyositis (odds ratio [OR] 2.3, 95% confidence interval [95% CI] 0.9-5.8) and with the proportion of patients expressing anti-Mi-2 autoantibodies (OR 6.0, 95% CI 1.1-34.1). Modeling of these data showed that these associations were confined to women (OR 3.8, 95% CI 1.3-11.0 and OR 17.3, 95% CI 1.8-162.4, respectively) and suggests that sex influences the effects of UV radiation on autoimmune disorders. Significant associations were not observed in men, nor were UV radiation levels related to the presence of antisynthetase or anti-signal recognition particle autoantibodies. CONCLUSION: This first study of the distribution of myositis phenotypes and UV radiation exposure in the US showed that UV radiation may modulate the clinical and immunologic expression of autoimmune disease in women. Further investigation of the mechanisms by which these effects are produced may provide insights into pathogenesis and suggest therapeutic or preventative strategies.
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BACKGROUND In Parkinson's disease (PD), bradykinesia, or slowness of movement, only appears after a large striatal dopamine depletion. Compensatory mechanisms probably play a role in this delayed appearance of symptoms. OBJECTIVE Our hypothesis is that the striatal direct and indirect pathways participate in these compensatory mechanisms. METHODS We used the unilateral 6-hydroxydopamine (6-OHDA) rat model of PD and control animals. Four weeks after the lesion, the spontaneous locomotor activity of the rats was measured and then the animals were killed and their brain extracted. We quantified the mRNA expression of markers of the striatal direct and indirect pathways as well as the nigral expression of dopamine transporter (DAT) and tyrosine hydroxylase (TH) mRNA. We also carried out an immunohistochemistry for the striatal TH protein expression. RESULTS As expected, the unilateral 6-OHDA rats presented a tendency to an ipsilateral head turning and a low locomotor velocity. In 6-OHDA rats only, we observed a significant and positive correlation between locomotor velocity and both D1-class dopamine receptor (D1R) (direct pathway) and enkephalin (ENK) (indirect pathway) mRNA in the lesioned striatum, as well as between D1R and ENK mRNA. CONCLUSIONS Our results demonstrate a strong relationship between both direct and indirect pathways and spontaneous locomotor activity in the parkinsonian rat model. We suggest a synergy between both pathways which could play a role in compensatory mechanisms and may contribute to the delayed appearance of bradykinesia in PD.
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Why does Adrian Leverkühn choose a Shakespeare play for his major first and his first twelve-tone composition? Why in particular a Shakespeare comedy? And why, of all comedies, Love’s Labour’s Lost? Why does he start working on it in Munich? Why does his work there soon come to a halt? Why does it prosper only in Italy? And why does he eventually return to Upper Bavaria so as to complete it? Why is he said to have completed the opera exactly one hundred years ago? And why, finally, is it first performed only after the outbreak of the war and then, surprisingly, in a German adaptation? In order to answer these and similar questions, this paper sets out to re-contextualise Doktor Faustus with regard to discourse history and re-read the novel from a gender-theoretical perspective. The leading hypothesis is that Thomas Mann’s novel belongs to the proto-history of feminist Shakespeare reception, an assumption to be substantiated through an analysis of settings, locations and the constructions of space.
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Mutations of STAT3 underlie the autosomal dominant form of hyperimmunoglobulin E syndrome (HIES). STAT3 has critical roles in immune cells and thus, hematopoietic stem cell transplantation (HSCT), might be a reasonable therapeutic strategy in this disease. However, STAT3 also has critical functions in nonhematopoietic cells and dissecting the protean roles of STAT3 is limited by the lethality associated with germline deletion of Stat3. Thus, predicting the efficacy of HSCT for HIES is difficult. To begin to dissect the importance of STAT3 in hematopoietic and nonhematopoietic cells as it relates to HIES, we generated a mouse model of this disease. We found that these transgenic mice recapitulate multiple aspects of HIES, including elevated serum IgE and failure to generate Th17 cells. We found that these mice were susceptible to bacterial infection that was partially corrected by HSCT using wild-type bone marrow, emphasizing the role played by the epithelium in the pathophysiology of HIES.
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A measurement of the mass difference between top and anti-top quarks is presented. In a 4.7 fb−14.7 fb−1 data sample of proton–proton collisions at View the MathML sources=7 TeV recorded with the ATLAS detector at the LHC, events consistent with View the MathML sourcett¯ production and decay into a single charged lepton final state are reconstructed. For each event, the mass difference between the top and anti-top quark candidate is calculated. A two b -tag requirement is used in order to reduce the background contribution. A maximum likelihood fit to these per-event mass differences yields View the MathML sourceΔm≡mt−mt¯=0.67±0.61(stat)±0.41(syst) GeV, consistent with CPT invariance.
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As a consequence of artificial selection for specific traits, crop plants underwent considerable genotypic and phenotypic changes during the process of domestication. These changes may have led to reduced resistance in the cultivated plant due to shifts in resource allocation from defensive traits to increased growth rates and yield. Modern maize (Zea mays ssp. mays) was domesticated from its ancestor Balsas teosinte (Z. mays ssp. parviglumis) approximately 9000 years ago. Although maize displays a high genetic overlap with its direct ancestor and other annual teosintes, several studies show that maize and its ancestors differ in their resistance phenotypes with teosintes being less susceptible to herbivore damage. However, the underlying mechanisms are poorly understood. Here we addressed the question to what extent maize domestication has affected two crucial chemical and one physical defence traits and whether differences in their expression may explain the differences in herbivore resistance levels. The ontogenetic trajectories of 1,4-benzoxazin-3-ones, maysin and leaf toughness were monitored for different leaf types across several maize cultivars and teosinte accessions during early vegetative growth stages. We found significant quantitative and qualitative differences in 1,4-benzoxazin-3-one accumulation in an initial pairwise comparison, but we did not find consistent differences between wild and cultivated genotypes during a more thorough examination employing several cultivars/accessions. Yet, 1,4-benzoxazin-3-one levels tended to decline more rapidly with plant age in the modern maize cultivars. Foliar maysin levels and leaf toughness increased with plant age in a leaf-specific manner, but were also unaffected by domestication. Based on our findings we suggest that defence traits other than the ones that were investigated are responsible for the observed differences in herbivore resistance between teosinte and maize. Furthermore, our results indicate that single pairwise comparisons may lead to false conclusions regarding the effects of domestication on defensive and possibly other traits.
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To avoid the undesired deprotonation during the addition of organolithium and organomagnesium reagents to ketones, the thioiminium salts, easily prepared from lactams and amides are converted into 2,2-disubstituted and 2-monosubstituted amines by reaction with simple nucleophiles such as organocerium and organocopper reagents. The reaction of thioiminium iodides with organocerium reagents derived by transmetalation of corresponding lithium reagents with anhydrous cerium(III) chloride has been investigated. These thioiminium iodides act as good electrophiles and accept alkylceriums towards bisaddition. The newly synthesized amines have been characterized by 1H and 13C NMR, IR and mass spectra. The amines have been converted into their hydrochlorides and characterized by COSY. These hydrochlorides have been subjected to antimicrobial screening with clinically isolated microorganisms, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi and Candida albicans. The hydrochlorides show quite good activity against these bacteria and fungus.
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In a mouse tumour model for hereditary breast cancer, we previously explored the anti-cancer effects of docetaxel, ritonavir and the combination of both and studied the effect of ritonavir on the intratumoural concentration of docetaxel. The objective of the current study was to apply pharmacokinetic (PK)-pharmacodynamic (PD) modelling on this previous study to further elucidate and quantify the effects of docetaxel when co-administered with ritonavir. PK models of docetaxel and ritonavir in plasma and in tumour were developed. The effect of ritonavir on docetaxel concentration in the systemic circulation of Cyp3a knock-out mice and in the implanted tumour (with inherent Cyp3a expression) was studied, respectively. Subsequently, we designed a tumour growth inhibition model that included the inhibitory effects of both docetaxel and ritonavir. Ritonavir decreased docetaxel systemic clearance with 8% (relative standard error 0.4%) in the co-treated group compared to that in the docetaxel only-treated group. The docetaxel concentration in tumour tissues was significantly increased by ritonavir with mean area under the concentration-time curve 2.5-fold higher when combined with ritonavir. Observed tumour volume profiles in mice could be properly described by the PK/PD model. In the co-treated group, the enhanced anti-tumour effect was mainly due to increased docetaxel tumour concentration; however, we demonstrated a small but significant anti-tumour effect of ritonavir addition (p value <0.001). In conclusion, we showed that the increased anti-tumour effect observed when docetaxel is combined with ritonavir is mainly caused by enhanced docetaxel tumour concentration and to a minor extent by a direct anti-tumour effect of ritonavir.
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Moraxella catarrhalis is a common pathogen of the human respiratory tract. Multidrug efflux pumps play a major role in antibiotic resistance and virulence in many Gram-negative organisms. In the present study, the role of the AcrAB-OprM efflux pump in antibiotic resistance was investigated by constructing mutants that lack the acrA, acrB, and oprM genes in M. catarrhalis strain O35E. We observed a moderate (1.5-fold) decrease in the MICs of amoxicillin and cefotaxime and a marked (4.7-fold) decrease in the MICs of clarithromycin for acrA, acrB, and oprM mutants in comparison with the wild-type O35E strain. Exposure of the M. catarrhalis strains O35E and 300 to amoxicillin triggered an increased transcription of all AcrAB-OprM pump genes, and exposure of strains O35E, 300, and 415 to clarithromycin enhanced the expression of acrA and oprM mRNA. Inactivation of the AcrAB-OprM efflux pump genes demonstrated a decreased ability to invade epithelial cells compared to the parental strain, suggesting that acrA, acrB, and oprM are required for efficient invasion of human pharyngeal epithelial cells. Cold shock increases the expression of AcrAB-OprM efflux pump genes in all three M. catarrhalis strains tested. Increased expression of AcrAB-OprM pump genes after cold shock leads to a lower accumulation of Hoechst 33342 (H33342), a substrate of AcrAB-OprM efflux pumps, indicating that cold shock results in increased efflux activity. In conclusion, the AcrAB-OprM efflux pump appears to play a role in the antibiotic resistance and virulence of M. catarrhalis and is involved in the cold shock response.