The CTFA Evaluation of Alternatives Program: an evaluation of in vitro alternatives to the Draize primary eye irritation test. (Phase III) surfactant-based formulations

The CTFA Evaluation of Alternatives Program is an evaluation of the relationship between data from the Draize primary eye irritation test and comparable data from a selection of promising in vitro eye irritation tests. In Phase III, data from the Draize test and 41 in vitro endpoints on 25 representative surfactant-based personal care formulations were compared. As in Phase I and Phase II, regression modelling of the relationship between maximum average Draize score (MAS) and in vitro endpoint was the primary approach adopted for evaluating in vitro assay performance. The degree of confidence in prediction of MAS for a given in vitro endpoint is quantified in terms of the relative widths of prediction intervals constructed about the fitted regression curve. Prediction intervals reflect not only the error attributed to the model but also the material-specific components of variation in both the Draize and the in vitro assays. Among the in vitro assays selected for regression modeling in Phase III, the relationship between MAS and in vitro score was relatively well defined. The prediction bounds on MAS were most narrow for materials at the lower or upper end of the effective irritation range (MAS = 0-45), where variability in MAS was smallest. This, the confidence with which the MAS of surfactant-based formulations is predicted is greatest when MAS approaches zero or when MAS approaches 45 (no comment is made on prediction of MAS > 45 since extrapolation beyond the range of observed data is not possible). No single in vitro endpoint was found to exhibit relative superiority with regard to prediction of MAS. Variability associated with Draize test outcome (e.g. in MAS values) must be considered in any future comparisons of in vivo and in vitro test results if the purpose is to predict in vivo response using in vitro data.     

Procedure for analysis of radium in freshwaters by adsorption on basic lead rhodizonate

Radium analysis is carried out by batch adsorption from natural waters on basic lead rhodizonate supported on charcoal, LERHO, starting from 2-L samples. 133Ba is added to allow the measurement of the overall chemical yield by gamma counting. Radium is recovered with a few milliliters of 1.5 M HCl, and lead is removed by a chromatographic column filled with Dowex 2 x 8. Finally 50 micrograms of barium carrier is added, and the radium is coprecipitated as sulfate on a preformed bed of barium sulfate, to prepare a sample suitable for alpha and gamma counting. The detection limit of the proposed method is 0.002 Bq/L 226Ra. This value is far beyond the radium activity admissible for drinking waters. Due to lack of appropriate samples, the procedure was tested using mineral waters spiked with 226Ra and two commercially available mineral waters with very low radium contents.     

Attempting to fathom the unfathomable: descriptive views of spirituality

PURPOSE: To evaluate short-term efficacy of awareness programs (AP) in reducing coronary heart disease risk factors (CHDRF). METHODS: High risk hypercholesterolemic patients were divided in 2 groups during 16 weeks. Group A (n = 417, 54.3 +/- 10.0 years, 55% males) received verbal and written orientation on CHDRF control, and group B (n = 180, 54.4 +/- 10.9 years, 45% males) received only verbal orientation. All participants received pravastatin 10 mg q.d. for 12 weeks. The evolution of body weight, arterial pressure, lipid profile, Castelli's I and II indexes (TC/HDL and LDL/HDL), and Framingham scores were evaluated. RESULTS: At baseline, A had a lower HDL-C (40.0 +/- 11.0 vs 43.0 +/- 11.0 mg/dl, p = 0.013) and a higher index I (8.2 +/- 3.0 vs 7.6 +/- 2.3, p = 0.008) than B. After 16 weeks, A had greater change than B in TC (-28.0 vs -25.0, p < 0.05), LDL-C (-29.0 vs -27.6, p < 0.05), HDL-C levels (+13.7 vs +10.8, p < 0.05) and in the Castelli's Index (-39.0 vs -33.0; p < 0.05). In both groups pravastatin use potentialized the effects of diet on the lipid profile. CONCLUSION: The AP seemed to be more effective than verbal orientation alone in CHDRF reduction at short-term.     

Acquired inhibitors to factors V and X after exposure to topical thrombin: interference with monitoring of low molecular weight heparin and warfarin

Repeated surgical exposure to topical bovine thrombin is known to be associated with the development of antibodies to bovine and human thrombin and factor V. This is demonstrated by abnormalities of in vitro coagulation assays and, rarely, postoperative bleeding. We describe a 4-year-old child in whom an antibody to bovine factor X developed after cardiac surgery; this antibody interfered with the heparin anti-Xa assay, thereby complicating the monitoring of heparin therapy.     

Kainate-induced apoptosis in cultured murine cerebellar granule cells elevates expression of the cell cycle gene cyclin D1

Recent evidence suggests that neuronal apoptosis is the consequence of an inappropriate reentry into the cell cycle. Expression of the cell cycle gene cyclin D1, a G1-phase cell cycle regulator, was examined in primary cultures of murine cerebellar granule cells (CGCs) during kainate (KA)-mediated apoptosis. Using cultures of CGCs, we found that a 24-h exposure to KA (1-3,000 microM) induced a concentration-dependent cell death with neurons exhibiting characteristic apoptotic morphology and extensive labeling using the terminal transferase-mediated nick end-DNA labeling (TUNEL) method. KA induced a time- and concentration-dependent increase in expression of cyclin D1 as determined by immunocytochemistry and western blot analysis. KA-induced apoptosis and cyclin D1 expression exhibited a similar concentration dependence and were significantly attenuated by the non-NMDA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (50 microM), indicating a KA receptor-mediated effect. Here we present evidence for the first time that KA-induced apoptosis in cultured CGCs involves the induction of cyclin D1, suggesting its involvement in excitotoxic receptor-mediated apoptosis.     

Transrectal ultrasound applicator for prostate heating monitored using MRI thermometry

PURPOSE: For potential localized hyperthermia treatment of tumors within the prostate, an ultrasound applicator consisting entirely of nonmagnetic materials for use with magnetic resonance imaging (MRI) has been developed and tested on muscle tissue ex vivo and in vivo. METHODS AND MATERIALS: A partial-cylindrical intracavitary transducer consisting of 16 elements in a 4 x 4 pattern was constructed. It produced a radially propagating acoustic pressure field. Each element of this array (1.5 x 0.75 cm), operating at 1.5 MHz, could be separately powered to produce a desired energy deposition pattern within a target volume. Spatial and temporal temperature elevations were determined using the temperature-dependent proton resonant frequency (PRF) shift and phase subtraction of MR images acquired during ultrasonic heating. Four rabbits were exposed to the ultrasound to raise the local tissue temperature to 45 degrees C for 25 minutes. Six experiments compared thermocouple temperature results to PRF shift temperature results. RESULTS: The tests showed that the multi-element ultrasound applicator was MRI-compatible and allowed imaging during sonication. The induced temperature distribution could be controlled by monitoring the RF power to each transducer element. Therapeutic temperature elevations were easily achieved in vivo at power levels that were about 16% of the maximum system power. From the six thermocouple experiments, comparison between the thermocouple temperature and the PRF temperature yielded an average error of 0.34+/-0.36 degrees C. CONCLUSIONS: The MRI-compatible intracavitary applicator and driving system was able to control the ultrasound field and temperature pattern in vivo. MRI thermometry using the PRF shift can provide adequate temperature accuracy and stability for controlling the temperature distribution.