Fluorescent substituted amidines of benzanthrone: synthesis, spectroscopy and quantum chemical calculations.

Several new substituted amidine derivatives of benzanthrone were synthesized by a condensation reaction from 3-aminobenzo[de]anthracen-7-one and appropriate aromatic and aliphatic amides. The obtained derivatives have a bright yellow or orange fluorescence in organic solvents and in solid state. The novel benzanthrone derivatives were characterized by TLC analysis, (1)H NMR, IR, MS, UV/vis, and fluorescence spectroscopy. The solvent effect on photophysical behaviors of these dyes was investigated, and the results showed that the Stoke's shift increased, whereas quantum yield decreased with the growth of the solvent polarity. The structure of some dyes was confirmed by the X-ray single crystal structure analysis. AM1, ZINDO/S and ab initio calculations using Gaussian software were carried out to estimate the electron system of structures. The calculations show planar configurations for the aromatic core of these compounds and two possible orientations of amidine substituents. The calculation results correlate well with red-shifted absorption and emission spectra of compounds.

Correlation of altered blood albumin characteristics and lymphocyte populations to tumor stage in gastrointestinal cancer patients.

The fluorescent probe ABM was used to characterize lymphocyte membranes and blood plasma albumin from cancer patients suffering from colorectal cancer or gastric cancers at Stages II-IV. The aim of these studies was to evaluate the potential utility of measures of ABM fluorescence intensity as a standard tool in the analyses of host immune status and for a clinical interpretation of alterations in albumin per se and lymphocyte functional activity in cancer patients. The fluorescence intensity of ABM in the blood plasma decreased from control values and showed specific differences in each of the differing patients groups; these changes corresponded to cancer stage. The significant decrease in ABM fluorescence in the plasma could be explained, in part, by a diminished binding capacity of the albumin of these patients. The lymphocyte distribution among the subsets of patients also differed. Interestingly, the ABM fluorescence in the cell suspension and blood plasma was also found to correlate with select immunological parameters (CD4(+):CD8(+) ratios, lymphocyte counts, etc.) in the patients. These results obtained here showed that there was a strong agreement between changes in ABM spectral characteristics and both clinical and pathological estimates of disease (i.e., gastrointestinal cancers) severity. Thus, the use of ABM spectroscopy appears to be another tool that might be of some used by clinicians to monitor the course of certain diseases, such as gastrointestinal cancers.

Altered plasma albumin characteristics and lymphocyte populations in gastrointestinal cancer patients: detection using modified fluorescence responses.

The fluorescent probe ABM (an amino derivative of benzanthrone) developed at Riga Technical University (Riga, Latvia) was used to characterize the blood plasma albumin of cancer patients (46 gastrointestinal cancer patients--30 with colorectal cancer in Stages II-IV and 16 with gastric cancer in Stage III) and of healthy controls. The fluorescence intensity of ABM in the blood plasma decreased from the control mean value and showed specific differences in the patients before (i.e., 24 hr pre-) and after (i.e., 10 day post-) they underwent a medically indicated surgical treatment, i.e., a gastric resection or gastroectomy for patients in the gastric cancer group or a colorectal resection for patients in the colorectum cancer group. The significant decrease in the ABM fluorescence in the blood plasma could be explained, in part, by a diminished binding capacity of the albumin of these patients. In fact, before surgery, there was a strong reduction in binding constant (K(a)) value for the probe observed in the plasma samples from these patients as compared with the value obtained with the plasma of the healthy donors. The lymphocyte distribution among the subsets also differed between the groups. Surgical treatment affected several immunological parameters and appeared to elevate the functional status of lymphocytes. Interestingly, the ABM fluorescence in the blood plasma was also seen to correlate with select immunological parameters (CD4+:CD8+ ratios, levels of CD38+ cells, etc.) both before and after the patients' operations. The results in the present study suggest that measures of ABM fluorescence intensity values for plasma albumin and/or especially of lymphocytes (as reflections of their functional activity) might be a useful tool in the evaluation of the immune status of gastrointestinal cancer patients.