RESUMEN
Surface enhanced Raman scattering of benzotriazole in aqueous silver sol at pH approximately 9 has been investigated. The spectra of the molecule at various concentrations were recorded and the maximum enhancement was observed with a 10(-5) M solution. From the comparison of the surface enhanced Raman spectra with the conventional Raman spectra and applying "surface selection rule", it is inferred that the molecular ion interacts with the silver sol via the nitrogen atoms of the benzotriazole ring and the molecule assumes a near "end-on" orientation.
Asunto(s)
Nitrógeno/química , Espectrometría Raman/métodos , Triazoles/química , Argón , Relación Dosis-Respuesta a Droga , Concentración de Iones de Hidrógeno , Cinética , Rayos Láser , Modelos Químicos , Plata/química , Espectrofotometría , Rayos UltravioletaRESUMEN
High-resolution FTIR data of carbonyl fluoride in the region of the C-O stretch nu1 fundamental have been analyzed. Satisfactory interpretation of the spectral data required a rigorous analysis that involved the inclusion of Fermi resonance with the 2nu2 state and Coriolis interaction with the 2nu3 + nu6 dark state. Deperturbed molecular constants for the three interacting states as well as perturbation parameters that fit the data within the limits of the experimental accuracy of approximately 0.00035 cm-1 have been obtained. Interesting evidence of "axis interchange" in the 2nu2 state has been observed. Copyright 1997 Academic Press. Copyright 1997Academic Press
RESUMEN
Enhanced expression of the epidermal growth factor receptor (EGFR) or its ligands, epidermal growth factor (EGF) and transforming growth factor alpha (TGF-alpha) can increase signalling via receptor-mediated pathways which may lead to excessive proliferation and cellular transformation. Such autocrine regulation of growth has been demonstrated for prostate cancer cell lines in culture but its role in prostate cancer in vivo has not been established. To assess the potential of such a mechanism, we have examined the pathway components in prostate carcinomas (CaP) in comparison with non-malignant benign prostatic hyperplasias (BPH). In the present study, we investigate the dosage, structure and expression of EGF, TGF-alpha and EGFR genes in a series of 34 human prostate samples and 3 prostate cancer cell lines. All of the samples contained transcripts from each of the genes. The expression of pre-pro-TGF-alpha mRNA and pre-pro-EGF mRNA were significantly higher in CaP (n = 13) than BPH (n = 21) specimens (p < 0.05). The androgen-responsive prostatic carcinoma cell line, LNCaP, expressed high levels of EGF mRNA while the androgen-independent DU145 and PC-3 cell lines expressed high levels of TGF-alpha mRNA and EGFR mRNA. In general, overexpression of these mRNAs was not associated with amplification or detectable gene rearrangement; only DU145 cells demonstrated any alteration in these genes, with apparent amplification of the TGF-alpha gene. Relative to BPH, all prostate carcinomas and cell lines studied had elevated levels of mRNA for one or both mRNA coding for the ligands for EGFR.(ABSTRACT TRUNCATED AT 250 WORDS)