Identification of putative gene based markers of renal toxicity

This study, designed and conducted as part of the International Life Sciences Institute working group on the Application of Genomics and Proteomics, examined the changes in the expression profile of genes associated with the administration of three different nephrotoxicants--cisplatin, gentamicin, and puromycin--to assess the usefulness of microarrays in the understanding of mechanism(s) of nephrotoxicity. Male Sprague-Dawley rats were treated with daily doses of puromycin (5-20 mg/kg/day for 21 days), gentamicin (2-240 mg/kg/day for 7 days), or a single dose of cisplatin (0.1-5 mg/kg). Groups of rats were sacrificed at various times after administration of these compounds for standard clinical chemistry, urine analysis, and histological evaluation of the kidney. RNA was extracted from the kidney for microarray analysis. Principal component analysis and gene expression-based clustering of compound effects confirmed sample separation based on dose, time, and degree of renal toxicity. In addition, analysis of the profile components revealed some novel changes in the expression of genes that appeared to be associated with injury in specific portions of the nephron and reflected the mechanism of action of these various nephrotoxicants. For example, although puromycin is thought to specifically promote injury of the podocytes in the glomerulus, the changes in gene expression after chronic exposure of this compound suggested a pattern similar to the known proximal tubular nephrotoxicants cisplatin and gentamicin; this prediction was confirmed histologically. We conclude that renal gene expression profiling coupled with analysis of classical end points affords promising opportunities to reveal potential new mechanistic markers of renal toxicity.     

Determination of chromium, selenium, and molybdenum in a therapeutic diet

Monitoring both the trace element and main element content of drugs forms part of their quality control. Chromium, selenium and molybdenum were determined in therapeutic diet samples by inductively coupled plasma/mass spectrometry (ICP-MS) and electrothermal atomic absorption spectrometry (ET-AAS). Samples were digested by high pressure microwave digestion or by ashing in oven. ICP-MS measurements have demonstrated that the chromium determination in liquid therapeutic diet should be estimated on the basis of 53Cr. In solid samples in some cases the value for Cr was elevated in comparison with the Cr content found by ET-AAS. The content of selenium can be determined on the basis of 77Se or 82Se after appropriate interference correction. Molybdenum content was determined on the basis of 95Mo. Control measurements were made by ET-AAS. For quality assurance purposes some of the samples were analyzed by a control laboratory.     

Concentration of estrogen and progesterone receptors in normal and neoplastic tissue in patients with laryngeal neoplasm

The analysis of larynx cancer localisation inside the larynx and hypopharynx indicate that there are some places prone to cancerogenesis. Differences in morbidity, organ localisation and prognosis of larynx cancer can be explained not only by exogenic factors but also by endogenic ones, including hormones. The estrogen (ER) hormone receptor concentration and progesterone (PgR) concentration was estimated in the neoplastic tissue in 18 patients (16 men, 2 women). In the control group, in 10 patients (9 men, 1 women) the concentration receptor was assessed in surrounding, macroscopically unchanged tissue. The quality assessment was done both in cytoplasmatic and nuclear receptors. 6 specimens of neoplastic tissue was taken from vocal folds, 7 from vestibular folds, 2 from subglottic space, 2 from epiglottic petiolus and 1 from pyriform sinus. Control group consist of 10 healthy tissue specimens including 4 taken from the vocal cords. 4 from vestibular folds, 2 from free edge of epiglottis. All samples were examined by pathologist. The concentration of cytoplasmatic and nuclei receptors (ER and PgR) was estimated by immunoenzymatic essay by ER-EIA and PgR-EIA monoclonal antibodies (Abbott). The highest concentration of receptors in larynx cancer was stated in tissue coming from vestibular folds and epiglottic petiolus in healthy objects in the region of vestibular folds.     

Localization and measurement of extracellular plant galactosidases

A simple, rapid and sensitive procedure for the identification and determination of plant extracellular alpha-galactosidase and beta-galactosidase is described using callus cultures and seedlings from tomato. Synthetic substrates (1-naphthyl- and p-nitrophenyl-alpha-D- and beta-D-galactopyranosides) were used for the identification and determination of intracellular and extracellular activity of alpha-galactosidase and beta-galactosidase, respectively. Many iminosugars or azasugars are strong glycosidase inhibitors and some of them show promising chemotherapeutic effects against viral diseases, and are potentially antidiabetic agents, as well as antitumor agents. These facts initiated our interest in a rapid and sensitive assay to determine activity of alpha-galactosidase and beta-galactosidase in plant tissues. The results presented here show the potential of the assay of the activity of intracellular and extracellular galactosidases of plant origin in inhibitory and/or biotechnological studies.     

Determination of chromium and selected elements in multimineral and multivitamin preparations and in pharmaceutical raw material

The content of elements in pharmaceutical preparations is one of the indispensable factors of the evaluation of their quality. In the present work, the following macro- and microelements Ca, Cr, Cu, Fe, Mg, Mn, Mo, P, Se and Zn were determined in multimineral and multivitamin preparations and in pharmaceutical raw material. Inductively coupled plasma mass spectrometry (ICP-MS) and electrothermal atomic absorption spectrometry (ET AAS) were used throughout the study. The examined samples were dissolved in a high-pressure microwave system using concentrated nitric acid. The effect of the carbon residue in the digest solution on the determination result was eliminated by introducing an equation correcting the ArC+ interference with 52Cr.     

Laser surgery for the treatment of glottic carcinomas

PURPOSE: The standard treatment for patients with early glottic carcinoma in Israel has been radiotherapy. In recent years, encouraging results with laryngo-microscopic carbon dioxide laser surgery as a treatment for early glottic carcinoma has changed our treatment strategy. We conducted a retrospective study to investigate the results of carbon dioxide laser excisional technique for early glottic carcinoma (T1, T2). MATERIALS AND METHODS: Twenty-six had squamous cell carcinoma (SCC), (21 patients with T1 and 5 patients with T2 lesions), 3 had carcinoma in situ, (CIS) and 3 had verrucous carcinoma (VC). RESULTS: All patients were free of disease after salvage treatment at the most recent follow-up. CONCLUSIONS: Careful patient selection with endoscopic staging and strict follow-up are essential to secure good results in the treatment of carbon dioxide laser for early laryngeal carcinoma.     

Determination of 4-aminophenol impurities in selected pharmaceutical preparations by HPLC method with amperometric detection

4-Aminophenol (4-APh) is the main impurity present in preparations containing paracetamol. Using the cyclic voltammetry and differential pulse voltammetry methods, the electrode behaviour of 4-APh has been studied in various non-buffered and buffered solutions at glassy carbon and golden electrodes. By means of the high-performance liquid chromatography with amperometric detection (HPLC-EC), the dependency of current intensities of the 4-APh peaks on the potential in the range (0-600 mV in the pH range 2-5, the ionic strength of mobile phase ranging from 0.01 mol (-1) to 0.20 mol l(-1) LiCl, has been studied. While employing the HPLC-EC method in this work, a glassy carbon electrode was used as the amperometric detector. The optimal potential selected in this research was +325 mV. It was found that a 0.05 mol l(-1) LiCl solution, containing 18% of methanol, at pH 4.0 adjusted with orthophosphoric acid, is suitable for the separation of 4-APh and paracetamol from each other and from other pharmaceutical excipients present in tablets. By using the elaborated HPLC-EC method, the content of 4-APh (at concentrations from 4 ng ml(-1)) in the paracetamol from Aldrich and in tablets from different producers, containing 500 mg of paracetamol in a tablet was found. Statistical evaluation of the obtained results has shown that the proposed HPLC-EC method for the determination of 4-APh is characterized by a good accuracy and precision (RSD about 6%) and can be applied to routine investigations of pharmaceutical preparations in the form of tablets.