Immunohistochemical expression of P53 and cyclin D1 proteins in follicular thyroid tumors: evaluation of their significance

The sequential mutational events which may underlie the tumorigenesis of thyroid neoplasia are gradually becoming apparent. To clarify the role of P53 and cyclin D1 in the oncogenesis and tumor progression of thyroid neoplasms, we examined the immunoreactivity of these proteins in one hundred and thirty [130] thyroid tumors originating from the follicular epithelium using immunohistochemistry. The tumors were divided into two groups group I: included thirty five [35] follicular adenomas and group II: included ninety five [95] follicular carcinomas; 65 of which were well differentiated [WDC] while the remaining [30] were poorly differentiated [PDC]. P53 positivity was more frequent in group II [20/95; 21.1%] than in group I [6/35; 17.1%] and in PDC [11/30; 26.6%] than WDC [9/65; 13.8%]. On the other hand, cyclin D1 positivity was frequent in WDC [21/65; 32.3%] and rarely seen in adenoma group [2/35; 5.7%]. Co -positivity for P53 and cyclin D1 proteins was more observed in PDC [5/30; 16.7%] than in WDC [3/65; 4.6%]. The study suggested that cyclin DI may be involved in the thyroid oncogenesis and concluded that both proteins may be incriminated in the progression of follicular thyroid neoplasms. Moreover, we found that age at the time of diagnosis, the histologic differentiation, necrosis in primary tumor, extrathyroidal invasion and the presence of distant metastases are important prognostic and risk factors. In addition, our study revealed that the detection of P53, but not cyclin D1, in primary follicular carcinomas is a significant independent prognostic indicator which, together with the above mentioned important prognostic factors, may be of value in the theraputic planning of these tumors

High-performance liquid chromatographic analysis of three macrolide antibiotics in pharmaceutical formulations and in human plasma

A high-performance liquid chromatographic method, for the determination of three macrolide antibiotics [roxithromycin [RXE], erythromycin base [E] and erythromycin ethylsuccinate [EES]], is presented. Study of the optimum condition for separation and quantitation of these antibiotics indicated that chromatography is performed in the reversed-phase mode using a C-18 column at a temperature of 40C. The strength of phosphate buffer can be used to control selectivity of the separated compound. The addition of isopropanol to the mobile phase improves peak shapes for the compounds of interest. Validation data for the studied antibiotics is done on spiked human plasma samples after extraction by adopting a rapid and simple procedure. The intra- and inter-assay coefficients of variation were less than 5% for the spiked plasma and pharmaceutical dosage forms

Determination of trimebutine in human plasma by high perfor-mance liquid chromatography with ultra-violet detection

Simple and sensitive HPLC method for the determination of trimebutine in human plasma was described. For the best separation, a suitable mobile phase consisted of 0.05 M phosphate buffer adjusted to pH 3.5 with phosphoric acid-methanol-isopropanol [32: 58: 10 by volume] was investigated. The mobile phase was prepared to contain 0.006 g% of sodium lauryl sulfate. The drug after extraction from plasma was chromatographed on a C-18 column. Trimebutine and internal st and ard, propyl para-hydroxybenzoate sodium salt [PPB], were detected at 265 nm. Extraction of the drug from plasma was developed to be complete, simple and non-destructive for the active components. The intra- and inter-assay coefficients of variation were less than 5%. The detection limit [signal-to-noise ratio = 3] was 0.5 mug/ml for plasma and the linearity was valid up to 12 mug/ml. The assay was successfully applied to study the bioequivalency of two commercial products containing trimebutine maleate. The tested tables were bioequivalent to the reference tablets