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Calabrò C Albanese MP Lauriano ER Martella S Licata A 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2005,43(1):51-56
Histochemical and immunohistochemical study was carried out on nitrinergic innervation and neuroendocrine system in the gill epithelium of the abyssal fish Coelorhynchus coelorhynchus. The results showed that nNOS-positive nerve fibers, originating from the branchial arch were present in the subepithelial tissue of branchial primary filament. nNOS-positive neuroendocrine cells were also present in the primary filaments and secondary lamellae. Numerous mucous cells in the gill epithelium were AB/PAS-positive, while sialic acid was absent as confirmed by neuraminidase reaction and WGA lectin histochemistry. The mucus compounds in abyssal teleost fish are different from those found in pelagic species, being related to their living conditions. In abyssal species, greater numbers of chloride and neuroendocrine cells are involved in the movement of water and electrolytes. Neuroendocrine cells possess oxygen receptors which mediate the cardiovascular and ventilatory response to oxygen deficiency, as reported in teleost species. Besides, NO contributes through nervous stimulation to the regulation of vascular tone and blood circulation in the gill. 相似文献
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Giampuzzi M Oleggini R Albanese C Pestell R Di Donato A 《Biochimica et biophysica acta》2005,1745(3):370-381
Lysyl oxidase is the enzyme that is essential for collagen and elastin cross-linking. Previous investigations showed that lysyl oxidase is down-regulated in many human tumors and ras-transformed cells. Recently, we proved that antisense down-regulation of lysyl oxidase in NRK-49F cells induced phenotypic changes and oncogenic transformation, characterized by p21(ras) activation and beta-catenin/cyclin D1 up-regulation. In the present paper, we examined beta-catenin intracellular distribution and its association with E-cadherin. We observed an increased association between E-cadherin and beta-catenin in the lysyl-oxidase down-regulated cells during serum starvation. Moreover, we found that beta-catenin cytoplasmic and nuclear levels were increased, suggesting a failure of its down-regulation by the APC-GSK-3beta system, in particular the GSK-3beta phosphorylation of ser-33/37 and thr-41 of beta-catenin. Finally, we investigated the mechanisms leading to the observed cyclin D1 up-regulation. We showed that in the antisense lysyl oxidase cells the cyclin D1 promoter was activated through the LEF and the ATF/CRE sites in the proximal promoter. While the promoter activation through LEF is compatible with beta-catenin signaling, we investigated the possibility that the CRE-dependent activation might be linked to the down-regulation of lysyl oxidase. In fact, up-regulation of lysyl oxidase in a COS-7 cell model showed a significant diminution of the CREB protein binding to the cyclin D1 promoter, leading to a dramatic inhibition of its activity and a significant down-regulation of cyclin D1 protein level in vivo. Finally, our study describes some major anomalies occurring in lysyl oxidase down-regulated fibroblasts, related to beta-catenin signaling and cyclin D1 expression. 相似文献
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The purpose of this article is to report the clinical, radiographical and histological findings about a case of a young woman affected by a mandibular giant follicular cyst. Conservative tumor resection was followed by immediate reconstructive treatment using fresh frozen human bone graft, instead of autologous bone graft, as material for bone regeneration. Follicular cyst is a benign, non invasive lesion with slow but progressive growth. Radiological and histological examination of the lesion confirmed the presence of a follicular cyst which underwent biopsy evaluation before enucleation. According to literature, conservative treatment was performed with optimal prognosis. At 24?months post surgery no evidence of recurrency was objective; the CT scan revealed optimal bone formation inside the reconstructed site. The use of fresh frozen bone allograft, thanks to its osteoinductive and osteoconductive properties, can be a safe choice for reconstruction of bone defects after jaw cysts removal. 相似文献
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Phenotyping for Abiotic Stress Tolerance in Maize 总被引:1,自引:0,他引:1
Benhilda Masuka Jose Luis Araus Biswanath Das Kai Sonder Jill E.Cairns 《植物学报(英文版)》2012,54(4):238-249
The ability to quickly develop germplasm having tolerance to several complex polygenic inherited abiotic and biotic stresses combined is critical to the resilience of cropping systems in the face of climate change.Molecular breeding offers the tools to accelerate cereal breeding;however,suitable phenotyping proto-cols are essential to ensure that the much-anticipated benefits of molecular breeding can be realized.To facilitate the full potential of molecular tools,greater emphasis needs to be given to reducing the within-experimental site variability,application of stress and characterization of the environment and appropriate phenotyping tools.Yield is a function of many processes throughout the plantcycle,and thus integrative traits that encompass crop performance over time or organization level(i.e.canopy level) will provide a better alternative to instantaneous measurements which provide only a snapshot of a given plant process.Many new phenotyping tools based on remote sensing are now available including non-destructive measurements of growth-related parameters based on spectral reflectance and infrared thermometry to estimate plant water status.Here we describe key field phenotyping protocols for maize with emphasis on tolerance to drought and low nitrogen. 相似文献
27.
Luis MP Ceríaco 《Journal of ethnobiology and ethnomedicine》2012,8(1):1-13
Background
Human values and folklore of wildlife strongly influence the effectiveness of conservation efforts. These values and folklore may also vary with certain demographic characteristics such as gender, age, or education. Reptiles and amphibians are among the least appreciated of vertebrates and are victims of many negative values and wrong ideas resulting from the direct interpretation of folklore. We try to demonstrate how these values and folklore can affect the way people relate to them and also the possible conservation impacts on these animals.Methods
A questionnaire survey distributed to 514 people in the district of Évora, Portugal, was used to obtain data regarding the hypothesis that the existence of wrong ideas and negative values contributes to the phenomenon of human-associated persecution of these animals. A structural equation model was specified in order to confirm the hypothesis about the possible relationships between the presence of perceptions and negative values about amphibians and reptiles and persecution and anti-conservation attitudes. Sociodemographic variables were also added.Results
The results of the model suggest that the presence of folklore and negative values clearly predicts persecution and anti-conservation attitudes towards amphibians and reptiles. Also, the existence of folklore varies sociodemographically, but negative values concerning these animals are widespread in the population.Conclusions
With the use of structural equation models, this work is a contribution to the study of how certain ideas and values can directly influence human attitudes towards herpetofauna and how they can be a serious conservation issue. 相似文献28.
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Analysis of alpha-fetoprotein heterogeneity by an improved crossed immunoaffinoelectrophoretic technique 总被引:1,自引:0,他引:1
The crossed immunoaffinoelectrophoretic procedure described here for the analysis of alpha-fetoprotein heterogeneity includes three major modifications of a procedure previously used by others: impregnation of the second dimension gel with methylated sugar derivatives; rigorous gel washing at 37 degrees C with the same derivatives; and an immunostaining technique. These simple changes have resulted in clear, sharp electrophoretic patterns at levels of total alpha-fetoprotein as low as 50 ng/ml, a sensitivity not previously approached with the method. Individual peaks representing as little as 7.5 ng/ml can be identified. 相似文献