Long-term sealing efficacy of four root surface sealing materials used in endodontic leakage studies

Fifty extracted human maxillary anterior teeth were biomechanically instrumented and divided into five equal groups, four experimental and a control. The teeth in the experimental groups had their root surface coated with one of four sealants; epoxy, casting resin, sticky wax, or nail polish. The roots of the remaining teeth were not coated and served as controls. All of the teeth were mounted in the caps of scintillation vials. Five microliters of [3H]uridine were deposited in the root canal space and disintegration counts were obtained over time periods of 1, 4, 8, 12, and 36 wk. At the conclusion of the experiment, sticky wax was demonstrated to provide a superior seal (p < 0.0001).     

A randomized comparative study of the metabolic effects of two regimens of gestrinone in the treatment of endometriosis

OBJECTIVE: To study some of the metabolic effects of oral gestrinone on plasma lipoprotein risk markers for cardiovascular disease and on bone density, a risk marker for osteoporosis. DESIGN: Randomized double-blind study. SETTING: All patients were referred to Gynaecology Clinic of Royal Free Hospital Medical School. PATIENTS: Twenty premenopausal women with laparoscopically confirmed endometriosis. INTERVENTIONS: Subjects were randomized in a double-blind fashion to receive either 1.25 mg or 2.5 mg gestrinone two times per week for 6 months. MAIN OUTCOME MEASURE: Laparoscopy was performed before treatment, and clinical responses were determined by second laparoscopy after 6 months. Plasma lipid and bone density measurements during and after therapy were compared with baseline. RESULT: Median total endometriosis scores decreased from 7.5 to 1.0 in the 1.25-mg group and from 7.0 to 0 in the 2.5-mg group. There were no significant between-group differences in endometriosis scores. At both doses, bone density in the spine and the proximal femur was conserved, but plasma concentrations of low-density lipoproteins rose by 13% and those of high-density lipoproteins fell by 40%. CONCLUSIONS: Reducing the dose of gestrinone to 1.25 mg appeared to maintain the therapeutic effectiveness of this treatment but was still associated with potentially unfavorable effects on lipids and lipoproteins.     

Induction of atypical squamous metaplasia with benzo[a]pyrene in cultured hamster tracheas

Areas of hyperplasia were produced in hamster tracheal epithelium maintained in vitro by exposure to a suspension of benzo[a]pyrene (BP) in gelatin. Typical and atypical epiodermoid metaplasia were seen by 2 weeks. In atypical areas, cell nuclei were enlarged with prominent nucleoli, the cytoplasm contained dense bundles of tonofilaments and the cells were joined by numerous desmosomes. The peak response to the carcinogen was reached 4 weeks after the application of BP and consisted of extensive atypical epidermoid metaplasia. Tracheas treated with gelatin alone maintained a columnar epithelium for 6 weeks of culture. The characteristics of the metaplastic changes in vitro are essentially identical to those described after exposure of the hamster tracheobronchial epithelium to benzo[a]pyrene-ferric oxide in vivo.     

The apolipoprotein E epsilon 4 allele does not influence the clinical expression of the amyloid precursor protein gene codon 693 or 692 mutations

In 31 symptomatic and 5 asymptomatic carriers of the amyloid precursor protein (APP) gene codon 693 mutation, 10 family members without mutation, and 5 carriers of the APP gene codon 692 mutation (3 with early-onset Alzheimer dementia, 2 with cerebral hemorrhage), a high frequency of the apolipoprotein E epsilon 4 allele was found. Age at onset, age at death, occurrence of dementia, and number of strokes did not differ between APP gene mutation carriers with or without epsilon 4 allele, showing that the clinical expression of these APP mutations is not influenced by the apolipoprotein E gene.