Open-label pilot study of interferon gamma-1b in Friedreich ataxia

OBJECTIVES/AIMS

This is an open-label trial of the safety of interferon gamma-1b (IFN-γ) and its effect on frataxin levels and neurologic measures in 12 children with Friedreich ataxia.

MATERIALS AND METHODS

Interferon gamma-1b was administered via subcutaneous injection three times weekly. The dose increased from 10 to 50 mcg/m(2) during the first four weeks and then remained at 50 mcg/m(2) for final eight weeks. Safety assessments included laboratory testing, electrocardiogram, and monitoring of adverse events. The primary efficacy outcome measure was frataxin level in whole blood. Secondary measures included frataxin levels in multiple tissues, frataxin mRNA levels, Friedreich Ataxia Rating Scale (FARS) scores and other neurologic evaluations. Statistical analyses were performed via SAS and STATA.

RESULTS

Interferon gamma-1b was well tolerated with no serious adverse events, and only two subjects reporting severe adverse events and subsequent dose reductions. Small but significant changes in frataxin levels were observed in red blood cells, PBMC, and platelets after 12 weeks of treatment. However, the magnitude of change was small and varied between tissues. Mean improvement in FARS score was equivalent to roughly 18 months of disease progression after 12 weeks of treatment (P = 0.008). No other statistically significant changes were observed. No statistically significant relationships were observed between frataxin protein levels, FARS scores, and in vivo IFN-γ levels.

CONCLUSIONS

Interferon gamma-1b improved FARS scores without a clear relationship to changes in frataxin levels. Larger, longer placebo-controlled trials including biochemical assessments in affected tissues are necessary to evaluate fully the efficacy and utility of IFN-γ in FRDA.

A CAD/CAM system for the production of metal copings for porcelain-fused-to-metal restorations

A computer-aided design and manufacture system for the production of metal copings for porcelain-fused-to-metal restorations is described and evaluated. The three stages of production: digitizing, mathematical processing, and milling are described, with emphasis on the system's ability to produce metal copings for both single-unit and multiple-unit restorations. Evaluation of the marginal fit of the produced copings demonstrates the potential for clinically acceptable results.

Effect of impression materials and techniques on the marginal fit of metal castings

The effect of two impression materials used in three different techniques was tested for the accuracy of the marginal fit of metal castings. Sixty identically prepared Ivorine teeth were divided into groups of 20. The following methods were selected to make impressions: (1) putty in a metal stock tray with simultaneous elastomeric impression wash, (2) copper band relined with autopolymerizing acrylic resin and subsequent light-body elastomeric impression material, and (3) copper bands with modeling compound. Faciolingual sections of the Ivorine teeth with cemented metal castings were examined by scanning electron microscopy (SEM) at x 100 magnification. Measurements of the thickness of cement layers were calculated both manually and by use of a recently developed computerized method. The differences in the gingival marginal gaps between various impression materials and techniques at both the facial and lingual surfaces were not statistically significant.

The management of "asymptomatic" epidural hematomas. A prospective study

Standard neurosurgical management mandates prompt evacuation of all epidural hematomas to obtain a low incidence of mortality and morbidity. This dogma has recently been challenged. A number of authors have suggested that in selected cases small and moderate epidural hematomas may be managed conservatively with a normal outcome and without risk to the patient. The goal of this study was to define the clinical parameters that may aide in the management of patients with small epidural hematomas who were clinically asymptomatic at initial presentation because there was no clinical evidence of raised intracranial pressure or focal compression. A prospective study was conducted of 22 patients (17 males and five females) aged from 1 to 71 years, who had a small epidural hematoma diagnosed within 24 hours of trauma and were managed expectantly. Of these, 32% subsequently required evacuation of the epidural hematoma 1 to 10 days after the initial trauma. Analysis of the patients revealed that age, sex, Glasgow Coma Scale score, and initial size of the hematoma are not risk factors for deterioration. However, deterioration was seen in 55% of patients with a skull fracture transversing a meningeal artery, vein, or major sinus, and in 43% of those undergoing computerized tomography (CT) within 6 hours of trauma. In contrast, only 13% of patients in whom the diagnosis of a small epidural hematoma was delayed over 6 hours subsequently required evacuation of the epidural collection. Of patients with both risk factors, 71% required evacuation of the epidural hematoma. None of the patients suffered neurological sequelae attributable to this management protocol. It was concluded that patients with a small epidural hematoma, a fracture overlaying a major vessel or major sinus, and/or who are diagnosed less than 6 hours after trauma are at risk of subsequent deterioration and may require evacuation. Conversely, patients without these risk factors may be managed conservatively with repeat CT and careful neurological observation, because of the low risk of delayed deterioration.