An Improved Method of Removing Polyurethane Foam-Covered Gel Prostheses

One of the advantages of polyurethane foam-covered prostheses has been that in the first 5 to 10 years after their use, the amount of capsular contraction was found much less than when similar ``slick' prostheses were used. Another advance was their fixation to the surrounding tissue thus giving a more natural appearance and movement with the muscles when the arms were moved in any direction. The formation of a thick capsule also acted as a protection against gel granuloma due to rupture of the prosthesis and has been thought to be a factor in the lower capsule contraction rate. The greatest disadvantage has been that its removal was extremely difficult and this has continued up until the technique described in this paper has been introduced.     

Digital subtraction radiography for assessment of simulated root resorption cavities. Performance of conventional and reverse contrast modes

Abstract A previous study of the sensitivity and accuracy of a standardized radiographic technique for the disclosure of root cavities in a cadaver material indicated that it was not possible to perceive small artificial “resorption” cavities. Using the same material, the aim of the present study was to evaluate whether the use of subtraction radiography would improve the detection of root cavities. In an autopsy material of five mandibular blocks each containing two premolars, small, medium, and large cavities were drilled in the cervical, middle, and apical thirds of the proximal and oral root surfaces. Each jaw block was radiographed before (B) and after (A) cavity preparation with three different exposure times resulting in light, medium, and dark film densities. The radiographs were digitized. Digital subtraction was performed between the A- and B images of varying densities by a computer program developed for dental subtraction radiography. Conventional and reverse contrast modes of the subtraction image were assessed independently by four observers. The results showed small inter- and intraobserver differences in diagnostic accuracy for assessment of total number of root cavities. Original film density did not influence the diagnostic performance in the resulting subtraction image. Contrast mode in the subtraction image influenced diagnostic performance as the majority of observers did best with the reverse contrast mode (p<0.05). Some of the small root cavities were disclosed by the subtraction technique, but overall accuracy was not increased compared to conventional radiography.     

Visual function in Huntington's disease patients and presymptomatic gene carriers.

Disturbances of visual cognition, visuomotor performance, and visual memory have been described frequently in Huntington's disease (HD). Early stage visual abnormalities could contribute to these deficits. We evaluated visual processing in 20 control subjects who were non-gene carriers at risk for HD, nine presymptomatic gene-positive subjects, and eight subjects with a recent diagnosis of Huntington's disease. Visual perceptual tests of contrast sensitivity and motion discrimination were used to probe early stage visual processing. Extraocular movements were evaluated in a neurologic examination, and the Digit Symbol test was used to test visual motor performance. Contrast sensitivity did not differ among the three groups. Motion discrimination was impaired in HD subjects but not in the presymptomatic gene carriers when compared to gene noncarriers. Among gene carriers, impaired motion discrimination performance was associated with poorer Digit Symbol performance and extraocular abnormalities. These findings suggest that the early stages of HD are associated with disturbances of motion perception as well as disruptions of visual motor and ocular motor performance.     

Consistent stress profiles in mothers of children with autism

The present study extends the area of research on stress in parents of autistic children. In this study we used the Questionnaire on Resources and Stress (Holroyd, 1987) to compare the stress profiles across mothers (a) who lived in different cultural and geographic environments; (b) who had children of different ages; and (c) who had children with different functioning levels. Results showed a characteristic profile that was highly consistent across each of these subgroups. Major differences from the normative data occurred on scales measuring stress associated with dependency and management, cognitive impairment, limits on family opportunity, and life-span care. Results suggest the importance of developing treatment programs aimed at reducing stress in specific areas in families with autistic children.Orchard Mental Health CenterThis research was supported by U.S. Department of Education, NIDRR Cooperative Agreement No. G0087C0234 (Koegel and Dunlap), by U.S. Public Health Service Research Grants MH28210 (Koegel) and MH39434 (Schreibman) from the National Institute of Mental Health, by Grant No. G008530082 from the U.S. Department of Education, Handicapped Children's Early Education Program (Dunlap), and by Fogarty Senior International Fellowship 1 FOB TWO 1374-01 (Schreibman) from the Fogarty International Center of the National Institutes of Health. The authors acknowledge the contributions of Prof. Dr. med. Hedwig Amorosa, and Dorle Staniczek, Soz. Pad. of the Max Planck Institute for Psychiatry, Munich, West Germany, and express particular appreciation to Prof. Dr. med. D. Ploog, Director of the Institute.     

Erythromycin-Induced Immune Hemolytic Anemia

A 3-year-old female receiving Pediazole (erythromycin ethylsuccinate and sulfisoxazole) for tonsillitis and otitis media developed severe hemolytic anemia. No serum drug-dependent antibodies could be demonstrated with an in vitro 'immune-complex' method using Pediazole, pure erythromycin ethylsuccinate or pure sulfisoxazole. However, a method using red cells coated with erythromycin base showed in vitro lysis of the erythromycin-coated red cells. This is only the second case of immune hemolytic anemia associated with erythromycin and the first where in vitro drug-dependent hemolysis was demonstrable.     

Stability of risk factors for cardiovascular diseases in Portuguese children and adolescents from the Porto area.

An important aspect of preventive medicine is to identify subjects at risk as soon as possible, so preventive strategies can be introduced at early ages. The justification for this strategy is twofold: firstly, the assumption that children maintain a particular high value of a risk factor for disease throughout life; and secondly, the assumption that lowering the level of the risk factor in early life will have a greater impact on the disease than will risk factor changes in later life. In epidemiology the analysis of such factors over time is referred to as tracking. Tracking analysis has been applied to risk factors for cardiovascular diseases (CVD) in pediatric years. The aims of this study were: I) to analyze the stability of biological risk factors [high blood pressure (BP), high percentage of fat mass (%FM) and high total cholesterol (TC)] and lifestyle risk factors [low physical activity index (PAI)] in isolation; and II) to analyze the stability of zero, one, two or three biological risk factors. There were two evaluations in 692 children and adolescents (325 boys and 367 girls), aged between 8 and 15 years. The quartiles, adjusted for age and gender, were the criterion used to identify subjects with biological risk factors (fourth quartile) and with lifestyle risk factors (first quartile) for CVD. The stability was calculated through the relative frequency of subjects who maintained or changed quartile between the two evaluations. There is stability for biological risk factors as well as for behavioral and/or lifestyle risk factors. However, the highest stability is seen in biological risk factors.     

Temazepam impairs effortful but not automatic processing of stimulus elements

The experiment investigated the effects in healthy volunteers of a single dose of temazepam (30 mg, oral) on effortful and automatic processing, by measuring memory for information and its context. Effortful processing was impaired, as shown by significant impairments in free recall of an 18-item list, but automatic processing was spared, as evidenced by no impairments in recall of the frequency of presentation, the colour, size or form of the items. In a second task, temazepam significantly impaired both recognition and recency memory of 30 items, although these scores were not correlated. Temazepam caused significant sedation, measured by an objective test and by subjective ratings, but this did not correlate with the memory impairments. The pattern of results is discussed with reference to the hypothesis that the memory impairments resulting from benzodiazepines are due to a reduction in information processing resources and thus affect effortful processing more than automatic processing.     

Hepatoprotective effects of diethylcarbamazine in acute liver damage induced by carbon tetrachloride in rats

This research was carried out to determine a potential role of leukotrienes in the acute hepatotoxicity induced by CC14 in rats. An inhibitor of leukotrienes biosynthesis, diethylcarbamazine (DEC, 25 and 50 mg ·kg-1 ip) exerted hepatoprotective effects, decreasing the activity of alanine aminotransfer-ase in serum and the concentration of liver triglycerides. DEC reduced histological damage of liver evidenced by electron microscopy. The hepatoprotective effects of DEC were dose-dependent. The results favor the role of leukotrienes in CC14 hepatotoxicity.     

Tumor targeting by an aptamer.

Aptamers are small oligonucleotides that are selected to bind tightly and specifically to a target molecule. We sought to determine whether aptamers have potential for in vivo delivery of radioisotopes or cytotoxic agents. METHODS: TTA1, an aptamer to the extracellular matrix protein tenascin-C, was prepared in fluorescent and radiolabeled forms. After in vivo administration, uptake and tumor distribution of Rhodamine Red-X-labeled aptamer was studied by fluorescence microscopy. In glioblastoma (U251) and breast cancer (MDA-MB-435) tumor xenografts, biodistribution and imaging studies were performed using TTA1 radiolabeled with (99m)Tc. Tenascin-C levels and tumor uptake were studied in a variety of additional human tumor xenografts. To assess the effect of radiometal chelate on biodistribution, mercapto-acetyl diglycine (MAG(2)) was compared with diethylenetriaminepentaacetic acid and with MAG(2)-3,400-molecular-weight PEG (PEG(3,400)). RESULTS: Intravenous injection of fluorescent aptamer TTA1 produced bright perivascular fluorescence in a xenografted human tumor within 10 min. In the ensuing 3 h, fluorescence diffused throughout the tumor. Labeled with (99m)Tc, TTA1 displayed rapid blood clearance, a half-life of less than 2 min, and rapid tumor penetration: 6% injected dose (%ID)/g at 10 min. Tumor retention was durable, with 2.7 %ID/g at 60 min and a long-lived phase that stabilized at 1 %ID/g. Rapid tumor uptake and blood clearance yielded a tumor-to-blood ratio of 50 within 3 h. Both renal and hepatic clearance pathways were observed. Using the (99m)Tc-labeled aptamer, images of glioblastoma and breast tumors were obtained by planar scintigraphy. Aptamer uptake, seen in several different human tumors, required the presence of the target protein, human tenascin-C. Modification of the MAG(2) radiometal chelator dramatically altered the uptake and clearance patterns. CONCLUSION: TTA1 is taken up by a variety of solid tumors including breast, glioblastoma, lung, and colon. Rapid uptake by tumors and rapid clearance from the blood and other nontarget tissues enables clear tumor imaging. As synthetic molecules, aptamers are readily modified in a site-specific manner. A variety of aptamer conjugates accumulate in tumors, suggesting imaging and potentially therapeutic applications.