138 research outputs found

    Evaluation of expression of P63 and amelogenin in human tooth germ and ameloblastoma

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    BACKGROUND: The study was undertaken to evaluate the expression of p63 and amelogenin in human tooth germs and ameloblastomas by immunohistochemistry to find out whether the pattern of expression was related to differentiation of ameloblasts. MATERIALS AND METHODS: In this study fifteen human tooth germs of late bell stage, six human tooth germs of early bell stage and fifteen ameloblastoma samples were included and expression pattern of p63 and amelogenin were evaluated individually in all the samples. RESULTS: During the early bell stage, p63 expression was intense throughout the enamel organ. But, during the late bell stage, the number and intensity of p63 expression decreases in the cells of enamel organ. The peripheral cells in the ameloblastoma shows variable pattern of p63 expression. Expression of amelogenin was first evident in the presecretory ameloblasts at the cusp tip, followed by secretory ameloblasts and progresses cervically. But in ten late bell stage tooth germs, amelogenin expression was negative in the secretory ameloblasts and positive only at the secreting end i.e. tomes process. Intense staining was evident at the enamel matrix and in some dentinal tubules nearer to enamel matrix secretion. No amelogenin expression was evident in the dental papilla cells or odontoblasts throughout odontogenesis with the exception of dental follicle. Amelogenin expression was absent in eleven cases of ameloblastoma, but in four cases positive expression was evident at the peripheral cells. CONCLUSION: In the present study, the expression pattern of p63 and amelogenin in human tooth germ and ameloblastoma correlates with cytodifferentiation of ameloblasts

    In vitro propagation of Hoya wightii ssp. palniensis K.T. Mathew, a highly vulnerable and endemic species of Western Ghats of Tamil Nadu, India

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    In vitro propagation of Hoya wightii ssp. palniensis (Asclepiadaceae), a highly vulnerable and endemic plant species of Western Ghats, Tamil Nadu, India was carried out. Shoot tip explants were cultured on MS medium fortified with cytokinins (KN, BA, 2-iP and TDZ) in various concentrations and in combination with auxins (IBA, IAA and NAA). High frequency of shoot bud proliferation and multiplication was observed on KN (4.65 ìM) + IBA (1.47 ìM). Multiple shoot induction efficiency was increased on ascorbic acid (100 mg/l) supplemented medium along with KN (4.65 ìM) +IBA (1.47 ìM). Rhizogenesis was observed on MS medium supplemented with IBA (0.98 ìM), plantlets produced through micropropagation were hardened with the survival success of 56%. The efficient plantlet regeneration protocol developed would aid ex situ conservation of this vulnerable species

    Apoptosis Inducing Effect of Plumbagin on Colonic Cancer Cells Depends on Expression of COX-2

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    Plumbagin, a quinonoid found in the plants of the Plumbaginaceae, possesses medicinal properties. In this study we investigated the anti-proliferative and apoptotic activity of plumbagin by using two human colonic cancer cell lines, HT29 and HCT15. IC50 of Plumbagin for HCT15 and HT29 cells (22.5 µM and 62.5 µM, respectively) were significantly different. To study the response of cancer cells during treatment strategies, cells were treated with two different concentrations, 15 µM, 30 µM for HCT15 and 50 µM, 75 µM for HT29 cells. Though activation of NFκB, Caspases-3, elevated levels of TNF-α, cytosolic Cytochrome C were seen in both HCT15 cells HT29 treated with plumbagin, aberrant apoptosis with decreased level of pEGFR, pAkt, pGsk-3β, PCNA and Cyclin D1was observed only in 15 µM and 30 µM plumbagin treated HCT15 and 75 µM plumbagin treated HT29 cells. This suggests that plumbagin induces apoptosis in both HCT15 cells and HT29 treated, whereas, proliferation was inhibited only in 15 µM and 30 µM plumbagin treated HCT15 and 75 µM plumbagin treated HT29 cells, but not in 50 µM plumbagin treated HT29 cells. Expression of COX-2 was decreased in 75 µM plumbagin treated HT29 cells when compared to 50 µM plumbagin treated HT29 cells, whereas HCT15 cells lack COX. Hence the observed resistance to induction of apoptosis in 50 µM plumbagin treated HT29 cells are attributed to the expression of COX-2. In conclusion, plumbagin induces apoptosis in colonic cancer cells through TNF-α mediated pathway depending on expression of COX-2 expression

    Optimization of xylanase production by filamentous fungi in solid state fermentation and scale-up to horizontal tube bioreactor

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    Five microorganisms, namely Aspergillus niger CECT 2700, A. niger CECT 2915, A. niger CECT 2088, Aspergillus terreus CECT 2808, and Rhizopus stolonifer CECT 2344, were grown on corncob to produce cell wall polysaccharide-degrading enzymes, mainly xylanases, by solid-state fermentation (SSF). A. niger CECT 2700 produced the highest amount of xylanases of 504±7 U/g dry corncob (dcc) after 3 days of fermentation. The optimization of the culture broth (5.0 g/L NaNO3, 1.3 g/L (NH4)2SO4, 4.5 g/L KH2PO4, and 3 g/L yeast extract) and operational conditions (5 g of bed loading, using an initial substrate to moistening medium of 1:3.6 (w/v)) allowed increasing the predicted maximal xylanase activity up to 2,452.7 U/g dcc. However, different pretreatments of materials, including destarching, autoclaving, microwave, and alkaline treatments, were detrimental. Finally, the process was successfully established in a laboratory-scale horizontal tube biore- actor, achieving the highest xylanase activity (2,926 U/g dcc) at a flow rate of 0.2 L/min. The result showed an overall 5.8-fold increase in xylanase activity after optimization of culture media, operational conditions, and scale-up.We are grateful to the Spanish Ministry of Science and Innovation for the financial support of this work (project CTQ2011-28967), which has partial financial support from the FEDER funds of the European Union; to the Leonardo da Vinci Programme for founding the stay of Felisbela Oliveira in Vigo University; to MAEC-AECID (Spanish Government) for the financial support for Perez-Bibbins, B. and to Spanish Ministry of Education, Culture and Sports for Perez-Rodriguez's FPU; and to Solla E. and Mendez J. (CACTI-University of Vigo) for their excellent technical assistance in microscopy

    Danger- and pathogen-associated molecular patterns recognition by pattern-recognition receptors and ion channels of the transient receptor potential family triggers the inflammasome activation in immune cells and sensory neurons.

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    An increasing number of studies show that the activation of the innate immune system and inflammatory mechanisms play an important role in the pathogenesis of numerous diseases. The innate immune system is present in almost all multicellular organisms and its activation occurs in response to pathogens or tissue injury via pattern-recognition receptors (PRRs) that recognize pathogen-associated molecular patterns (PAMPs) or danger-associated molecular patterns (DAMPs). Intracellular pathways, linking immune and inflammatory response to ion channel expression and function, have been recently identified. Among ion channels, the transient receptor potential (TRP) channels are a major family of non-selective cation-permeable channels that function as polymodal cellular sensors involved in many physiological and pathological processes.In this review, we summarize current knowledge of interactions between immune cells and PRRs and ion channels of TRP families with PAMPs and DAMPs to provide new insights into the pathogenesis of inflammatory diseases. TRP channels have been found to interfere with innate immunity via both nuclear factor-kB and procaspase-1 activation to generate the mature caspase-1 that cleaves pro-interleukin-1Ăź cytokine into the mature interleukin-1Ăź.Sensory neurons are also adapted to recognize dangers by virtue of their sensitivity to intense mechanical, thermal and irritant chemical stimuli. As immune cells, they possess many of the same molecular recognition pathways for danger. Thus, they express PRRs including Toll-like receptors 3, 4, 7, and 9, and stimulation by Toll-like receptor ligands leads to induction of inward currents and sensitization in TRPs. In addition, the expression of inflammasomes in neurons and the involvement of TRPs in central nervous system diseases strongly support a role of TRPs in inflammasome-mediated neurodegenerative pathologies. This field is still at its beginning and further studies may be required.Overall, these studies highlight the therapeutic potential of targeting the inflammasomes in proinflammatory, autoinflammatory and metabolic disorders associated with undesirable activation of the inflammasome by using specific TRP antagonists, anti-human TRP monoclonal antibody or different molecules able to abrogate the TRP channel-mediated inflammatory signals

    Danger- and pathogen-associated molecular patterns recognition by pattern-recognition receptors and ion channels of the transient receptor potential family triggers the inflammasome activation in immune cells and sensory neurons

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    Emerging roles of T helper 17 and regulatory T cells in lung cancer progression and metastasis

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