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31.
Our aim was to comprehensively analyze promoter hypermethylation of a panel of novel and known methylation markers for thyroid neoplasms and to establish their relationship with BRAF mutation and clinicopathologic parameters of thyroid cancer. A cohort of thyroid tumors, consisting of 44 cancers and 44 benign thyroid lesions, as well as 15 samples of adjacent normal thyroid tissue, was evaluated for BRAF mutation and promoter hypermethylation. Genes for quantitative methylation specific PCR (QMSP) were selected by a candidate gene approach. Twenty-two genes were tested: TSHR, RASSF1A, RARβ2, DAPK, hMLH1, ATM, S100, p16, CTNNB1, GSTP1, CALCA, TIMP3, TGFßR2, THBS1, MINT1, CTNNB1, MT1G, PAK3, NISCH, DCC, AIM1 and KIF1A. The PCR-based “mutector assay” was used to detect BRAF mutation. All p values reported are two sided. Considerable overlap was seen in the methylation markers among the different tissue groups. Significantly higher methylation frequency and level were observed for KIF1A and RARß2 in cancer samples compared with benign tumors. A negative correlation between BRAF mutation and RASSF1A methylation, and a positive correlation with RARß2 methylation were observed in accordance with previous results. In addition, positive correlation with TIMP3 and a marginal correlation with DCC methylation were observed. The present study constitutes a comprehensive promoter methylation profile of thyroid neoplasia and shows that results must be analyzed in a tissue-specific manner to identify clinically useful methylation markers. Integration of genetic and epigenetic changes in thyroid cancer will help identify relevant biologic pathways that drive its development.  相似文献   
32.
Nucleoside and nucleobase transporters are important for salvage of purines and pyrimidines and for transport of their analog drugs into cells. However, the pathways for nucleobase translocation in mammalian cells are not well characterized. We identified an Na-independent purine-selective nucleobase/nucleoside transport system in the nucleoside transporter-deficient PK15NTD cells. This transport system has 1,000-fold higher affinity for nucleobases than nucleosides with K(m) values of 2.5 +/- 0.7 microM for [(3)H]adenine, 6.4 +/- 0.5 microM for [(3)H]guanine, 1.1 +/- 0.1 mM for [(3)H]guanosine, and 4.2 +/- 0.5 mM [(3)H]adenosine. The uptake of [(3)H]guanine (0.05 microM) was inhibited by other nucleobases and nucleobase analog drugs (at 0.5-1 mM in the order of potency): 6-mercaptopurine = thioguanine = guanine > adenine > thymine = fluorouracil = uracil. Cytosine and methylcytosine had no effect. Nucleoside analog drugs with modification at 2' and/or 5 positions (all at 1 mM) were more potent than adenosine in competing the uptake of [(3)H]guanine: 2-chloro-2'-deoxyadenosine > 2-chloroadenosine > 2'3'-dideoxyadenosine = 2'-deoxyadenosine > 5-deoxyadenosine > adenosine. 2-Chloro-2'-deoxyadenosine and 2-chloroadenosine inhibited [(3)H]guanine uptake with IC(50) values of 68 +/- 5 and 99 +/- 10 microM, respectively. The nucleobase/nucleoside transporter was resistant to nitrobenzylthioinosine {6-[(4-nitrobenzyl) thiol]-9-beta-D-ribofuranosylpurine}, dipyridamole, and dilazep, but was inhibited by papaverine, the organic cation transporter inhibitor decynium-22 (IC(50) of approximately 1 microM), and by acidic pH (pH = 5.5). In conclusion, we have identified a mammalian purine-selective nucleobase/nucleoside transporter with high affinity for purine nucleobases. This transporter is potentially important for transporting naturally occurring purines and purine analog drugs into cells.  相似文献   
33.
An attempt has been taken to establish an efficient plant regeneration system in vitro from 3, 5, 7 and 9-days-old root segments of four Indica (Bangladeshi) rice genotypes. Genotypic effects were observed in callus induction and subsequent plant regeneration. Moreover, the stage of development of the root explants also played a significant role in callus formation and subsequent plant regeneration. Younger explants were more efficient in both callus induction and plant regeneration. Plants regenerated in vitro were successfully established in soil and produced fertile seeds.  相似文献   
34.
A field experiment was conducted to investigate the effect of some management practices to minimise jute yellow mosaic virus disease. The management practices were employed at natural condition and placed randomly with four replications. The treatments were spraying malathion 57 EC, rouging and field sanitation, top dressing of nitrogenous fertiliser, mulching with straw and untreated control. The highest percentage of mosaic incidence was recorded in control and the lowest incidence was recorded in top dressing of nitrogenous fertiliser. Among the treatments, top dressing of nitrogenous fertiliser showed the best performance in terms of increasing yield (3.05?t/ha). The second highest was obtained in rouging and field sanitation which was statistically similar to spraying malathion 57 EC. The best gross margin ($379.02/ha) and increase of gross margin (63.00%) compared to control were achieved in top dressing of nitrogenous fertiliser with the highest benefit-cost ratio (4.84). However, the treatments were found significantly profitable compared to the control indicating the usefulness of the cultural practices in integrated disease management programme for healthy and profitable jute cultivation.  相似文献   
35.
Avian influenza is a major animal and public health concern in Bangladesh. A decade after development and implementation of the first national avian influenza and human pandemic influenza preparedness and response plan in Bangladesh, a two-stage qualitative stakeholder analysis was performed in relation to the policy development process and the actual policy. This study specifically aimed to identify the future policy options to prevent and control avian influenza and other poultry-related zoonotic diseases in Bangladesh. It was recommended that the policy should be based on the One Health concept, be evidence-based, sustainable, reviewed and updated as necessary. The future policy environment that is suitable for developing and implementing these policies should take into account the following points: the need to formally engage multiple sectors, the need for clear and acceptable leadership, roles and responsibilities and the need for a common pool of resources and provision for transferring resources. Most of these recommendations are directed towards the Government of Bangladesh. However, other sectors, including research and poultry production stakeholders, also have a major role to play to inform policy making and actively participate in the multi-sectoral approach.  相似文献   
36.
Most of the available data on the nitric oxide (NO) pathway in the vasculature is derived from studies performed with cells isolated from conduit arteries. We investigated the expression and regulation of components of the NO synthase (NOS)-NO-cGMP pathway in endothelial cells from the mesenteric vascular bed. Basally, or in response to bradykinin, cultured mesenteric endothelial cells (MEC) do not release NO and do not express endothelial NOS protein. MEC treated with cytokines, but not untreated cells, express inducible NOS (iNOS) mRNA and protein, increase nitrite release, and stimulate cGMP accumulation in reporter smooth muscle cells. Pretreatment of MEC with genistein abolished the cytokine-induced iNOS expression. On the other hand, exposure of MEC to the microtubule depolymerizing agent colchicine did not affect the cytokine-induced increase in nitrite formation and iNOS protein expression, whereas it inhibited the induction of iNOS in smooth muscle cells. Collectively, our findings demonstrate that MEC do not express endothelial NOS but respond to inflammatory stimuli by expressing iNOS, a process that is blocked by tyrosine kinase inhibition but not by microtubule depolymerization.  相似文献   
37.
Dengue fever (DF) and dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) are considered the most important arthropod-borne viral diseases in terms of morbidity and mortality. The emergency and severity of dengue (Den) infections increase the necessity of an early, quick and effective dengue laboratory diagnostic. Viral isolation is considered a gold standard for diagnosis of dengue infection using monoclonal antibodies (mAbs) as a tool for determining serotype specificity. Alternatives have been used to improve sensitivity and time to dengue diagnosis. Based on the early expression of dengue C protein in the life cycle, we focused our study on the application of an anti-dengue 2 virus capsid protein mAb in dengue diagnosis. The kinetic expression of dengue-2 capsid in mosquito cells and its immuno-localization in experimentally infected suckling albin Swiss (OF-1) mice brain tissues was established. The results demonstrate the possible utility of this mAb in early dengue diagnosis versus traditional isolation. In addition, a preliminary study of an enzyme immunoassay method using 8H8 mAb for specific detection of dengue C protein antigen was performed, making possible recombinant C protein quantification. The results suggest that detection of dengue capsid protein could be useful in the diagnosis of early dengue infection.Key words: monoclonal antibodies, capsid protein, dengue virus, diagnosis, immunoassays  相似文献   
38.
39.
In the floriculture region of Tenancingo in the State of Mexico, the application of stabilized organic matter, such as vermicompost and leachates, contributes to improve the quality of the soil and plant nutrition. However, it is important to know the chemical composition of a vermicompost and the mineralization process. This is because the amount and speed of nutrient release which will be available to the crop will depend on that knowledge. The objective of the study was to evaluate the effect of the application of a vermicompost and leachates on various quantitative variables of Solidago x hybrid, and the mineralization of organic carbon under aerobic incubations. Vermicompost (74 and 36 g/kg soil), leachates (5 and 10 L/kg soil), 0.33 g/kg soil of chemical fertilizer Ca (NO3)2, and not treated soil (control) were applied under greenhouse conditions to evaluate their effects on plant growth variables. Mixtures of 100 g of soil with vermicompost and leachates were made in the laboratory which were incubated during 9 weeks to obtain the potentially mineralizable organic carbon (Corg PM) and the rate of mineralization (k) after adjusting an exponential model. In the greenhouse experiment there were no statistical differences after applying vermicompost and leachates on the quantitative variables (number of stems per plant, diameter of the panicle, fresh weight, plant length and stem diameter) with respect to the control (p>0.05). The effect among the applied doses was evident only for variables such as fresh weight, panicle length and stem diameter with respect to the control. In incubated soils, k values ranged between 0.209-0.325 C mg/kg soil/week. Only with the application of leachates in high doses two pools of organic matter were shown: one soluble labile (102.9 mg/kg soil) and the other hydrolysable (819 mg/kg soil). The soluble, labile fraction favored nutrient availability immediately after its application to the soil. However, a single pool of hydrolysable organic C (987-1074 mg/kg soil) was found when vermicompost was applied. It was associated with a release of organic matter during crop development, and to a possible stimulation of microbial activity. High values of electrical conductivity in vermicompost and leachates (8.2-11.7 mS/m) suggest a moderate application of both products.  相似文献   
40.
We investigated the efficacy of Ocimum basilicum (OB) essential oils for treating depression related behavioral, biochemical and histopathological changes caused by exposure to chronic unpredictable mild stress (CUMS) in mice and to explore the mechanism underlying the pathology. Male albino mice were divided into four groups: controls; CUMS; CUMS plus fluoxetine, the antidepressant administered for pharmacological validation of OB; and CUMS plus OB. Behavioral tests included the forced swim test (FST), elevated plus-maze (EPM) and the open ?eld test (OFT); these tests were performed at the end of the experiment. We assessed serum corticosterone level, protein, gene and immunoexpression of brain-derived neurotropic factor (BDNF) and glucocorticoid receptors (GRs) as well as immunoexpression of glial fibrillary acidic protein (GFAP), Ki67, caspase-3 in the hippocampus. CUMS caused depression in the mice as evidenced by prolonged immobility in the FST, prolonged time spent in the open arms during the EPM test and reduction of open field activity in the OFT. OB ameliorated the CUMS induced depressive status. OB significantly reduced the corticosterone level and up-regulated protein and gene expressions of BDNF and GR. OB reduced CUMS induced hippocampal neuron atrophy and apoptosis, and increased the number of the astrocytes and new nerve cells. OB significantly increased GFAP-positive cells as well as BDNF and GR immunoexpression in the hippocampus.  相似文献   
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