17 research outputs found

    p27(Kip1 )is expressed in proliferating cells in its form phosphorylated on threonine 187

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    BACKGROUND: G1/S cell cycle progression requires p27(Kip1 )(p27) proteolysis, which is triggered by its phosphorylation on threonine (Thr) 187. Since its levels are abundant in quiescent and scarce in cycling cells, p27 is an approved marker for quiescent cells, extensively used in histopathology and cancer research. METHODS: However here we showed that by using a specific phosphorylation site (pThr187) antibody, p27 is detectable also in proliferative compartments of normal, dysplastic and neoplastic tissues. RESULTS: In fact, whereas un-phosphorylated p27 and MIB-1 showed a significant inverse correlation (Spearman R = -0.55; p < 0,001), pThr187-p27 was positively and significantly correlated with MIB-1 expression (Spearman R = 0.88; p < 0,001). Thus proliferating cells only stain for pThr187-p27, whereas they are un-reactive with the regular p27 antibodies. However increasing the sensitivity of the immunocytochemistry (ICH) by the use of an ultra sensitive detection system based on tiramide signal amplification, simultaneous expression and colocalisation of both forms of p27 was shown in proliferating compartments nuclei by double immunofluorescence and laser scanning confocal microscopy studies. CONCLUSION: Overall, our data suggest that p27 expression also occurs in proliferating cells compartments and the combined use of both regular and phospho- p27 antibodies is suggested

    A Ten-microRNA Expression Signature Predicts Survival in Glioblastoma

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    Glioblastoma (GBM) is the most common and aggressive primary brain tumor with very poor patient median survival. To identify a microRNA (miRNA) expression signature that can predict GBM patient survival, we analyzed the miRNA expression data of GBM patients (n = 222) derived from The Cancer Genome Atlas (TCGA) dataset. We divided the patients randomly into training and testing sets with equal number in each group. We identified 10 significant miRNAs using Cox regression analysis on the training set and formulated a risk score based on the expression signature of these miRNAs that segregated the patients into high and low risk groups with significantly different survival times (hazard ratio [HR] = 2.4; 95% CI = 1.4–3.8; p<0.0001). Of these 10 miRNAs, 7 were found to be risky miRNAs and 3 were found to be protective. This signature was independently validated in the testing set (HR = 1.7; 95% CI = 1.1–2.8; p = 0.002). GBM patients with high risk scores had overall poor survival compared to the patients with low risk scores. Overall survival among the entire patient set was 35.0% at 2 years, 21.5% at 3 years, 18.5% at 4 years and 11.8% at 5 years in the low risk group, versus 11.0%, 5.5%, 0.0 and 0.0% respectively in the high risk group (HR = 2.0; 95% CI = 1.4–2.8; p<0.0001). Cox multivariate analysis with patient age as a covariate on the entire patient set identified risk score based on the 10 miRNA expression signature to be an independent predictor of patient survival (HR = 1.120; 95% CI = 1.04–1.20; p = 0.003). Thus we have identified a miRNA expression signature that can predict GBM patient survival. These findings may have implications in the understanding of gliomagenesis, development of targeted therapy and selection of high risk cancer patients for adjuvant therapy

    Synthesis and characterization of novel silane derivatives of phenothiazinium photosensitisers

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    Phenothiazine based dyes are widely explored dyes for their antibacterial and photosensitising applications. Despite their amazing optical and photosensitising (theranostic) properties, their usage in nanomedicine is very low compared to other organic dyes. This is due to the lack of reactive functional groups for encapsulating them into metal oxide nanoparticles. This work describes the synthesis of three different phenothiazinium alkoxysilane derivatives by oxidative amination of 10H-phenothiazine using amino alkoxysilanes. The new derivatives were characterized using NMR, FT-IR, DSC/TGA, and mass spectral studies. Optical and photosensitising properties (absorption spectrum, photostability, and singlet oxygen quantum yield) of the silane derivatives were investigated using UV–Visible spectroscopy. These compounds are suitable for conjugation with silica in the sol-gel synthesis of silica nanoparticles and silica surface coaters, which will reduce dye leakage and improve the dye efficacy in the treatment of cancer and light activated antimicrobial surfaces

    Novel polymorphs of n-[2-amino-4-(4-fluorobenzylamino)-phenyl] carbamic acid ethyl ester and processes thereof

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    The present invention relates to novel polymorphs of N-[2-amino-4-(4-fluorobenzylamino)-phenyl]carbamic acid ethyl ester, processes for preparing them, and pharmaceutical composition comprising them. In one aspect, the present invention relates to a novel crystalline polymorph of retigabine designated as crystalline Form I, characterized by XRPD having characteristic peaks at about 4.87, 5.04, 7.03, 9.74, 10.02, 11.6, 18.03, 19.9 and 28.5±0.2 degrees two-theta, which is substantially same as depicted in FIG. 1

    Carbohydrate coated fluorescent mesoporous silica particles for bacterial imaging

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    This work investigated the synthesis of carbohydrate functionalized methylene blue doped amine grafted mesoporous silica nanoparticles (MB AMSN) and their application in bioimaging. A single-pot synthesis methodology was developed via a modified co-condensation sol-gel technique for simultaneous incorporation of the dye molecule in the nanoparticles, with amine grafting for subsequent functionalization. The obtained nanoparticles (∼ 450 nm) are mesoporous and have a high surface area (538 m2/g), pore-volume (0.3 cm3/g), showed excellent UV-vis absorbance, and dye encapsulation efficiency (> 75 %). These fluorescent nanoparticles were further functionalized with carbohydrate molecules before application as contrast agents in bacterial cells. In the present study, gram-positive (E. coli) and gram-negative (B. subtilis) bacteria were used as model organisms. Confocal laser microscopy results showed that the nanoparticles are highly fluorescent, and SEM of glucose conjugated MB doped nanoparticles indicated close interaction with E. coli with no toxicity observed towards either bacterial cells. The results demonstrate that by suitable surface functionalization, the methylene blue doped silica nanoparticles can be used as bioimaging agents

    Novel stereospecific synthesis of (-) (2s, 3s)-1-dimethylamino-3-(3-methoxyphenyl)-2-methyl pentan-3-ol

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    The present invention relates to a novel stereospecific synthesis of (−)(2S,3S)-1-dimethylamino-3-(3-methoxyphenyl)-2-methyl pentan-3-ol an intermediate in the synthesis of 3-[(1R,2R)-3-(dimethylamino)-1-ethyl-2-methylpropyl]pheno
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