Radionuclide therapy of skin cancers and Bowen's disease using a specially designed skin patch

Skin cancer is the most common malignancy in humans. Therapeutic modalities for skin cancer are local destruction, radiotherapy and surgery. External radiation therapy leads to good results, however, generally 5-6 wk of treatment is needed to deliver optimal radiation dose to tumors. In this study, a beta-emitting radionuclide, 166Ho, impregnated in a specially designed patch, was used on superficial skin cancers and Bowen's disease for local irradiation. METHODS: Ten mice with chemically induced skin tumors were studied. Five-millimeter size patches containing 22.2-72.15 MBq (0.6-1.95 mCi) 166Ho were applied to the tumor surface for 1-2 hr. In a human trial, patients with squamous-cell carcinoma (n = 3), basal cell carcinoma (n = 1) and Bowen's disease (n = 1) were treated with patches containing 273.8-999 MBq (7.4-27 mCi) of 166Ho for 30 min to 1 hr. Pathologic examination was performed 4-7 wk after treatment in an animal model. Skin biopsy was performed 8 wk post-treatment in four patients. RESULTS: Tumor destruction was seen 1 wk post-treatment, however, radiation dermatitis or ulceration developed at the site of radionuclide application. Those reactions healed gradually with fibrosis or epithelialization, which was confirmed pathologically. No significant adverse reaction to radiation except subcutaneous fibrosis was found. CONCLUSION: Superficial skin tumors could be successfully treated by topical application of beta-emitting radionuclides.     

Influence of mineral admixtures on the alkali-aggregate reaction

Different mineral admixtures were used as cement replacements to study the alkali-aggregate reaction between quartzite and cement paste. The experimental program included expansion measurement of the mortar-bar specimens, observation of the microstructure, and analysis of the gel composition. Two Portland cements with different alkali contents were used to prepare mortar bars containing different amounts of natural pozzolan, fly-ash, and slag. Three natural pozzolans with different alkali contents were also utilized to assess the effect of their alkalies on the mortar expansion. The results indicate that not all gels are equally expansive and that mineral admixtures change the composition of the gel. The double layer theory is used to explain the expansion results of the mortar bars containing different levels and types of mineral admixtures. As this theory predicts, the experimental results show a strong negative correlation between expansion and the charge fraction of bivalent cations in the gel.     

Aspects of alkali treatment of sponge gourd (Luffa cylindrica) fibers on the flexural properties of polyester matrix composites

Sponge gourd (Luffa cylindrica) forms a natural mat that deviates the crack path in brittle thermoset resin matrix composites, leading to a controlled fracture mode and increasing the toughness of the composite. The use of luffa as reinforcement is, however, restricted by a very weak fiber–matrix interface. In this work, luffa fibers were alkali‐treated at two temperatures, with varying alkali concentrations. Although the surface analysis shows that the treatments promote a clear removal of the outer surface layer of the fibers with the exposition of the inner fibrillar structure and the consequent increase of the fiber surface area, only a secondary increase on the mechanical properties was obtained. The slight increase observed was attributed only to mechanical interlock. Long pullout lengths and neat fiber beads were the main features observed at the fracture surface of the treated and untreated fiber composites. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1927–1932, 2003     

Transient kinetics and thermodynamics of anthroylouabain binding to Na/K-ATPase

In this study the antiarrhythmic and the proarrhythmic activities of almokalant, a selective class III antiarrhythmic agent, were compared. The antiarrhythmic effect of the drug was tested in pentobarbital-anaesthetised rabbits. Arrhythmia was evoked by occluding and releasing the left circumflex coronary artery. Almokalant in a dose of 250 nmol/kg i.v., significantly decreased the incidence of reperfusion induced ventricular fibrillation (21% vs. 75% in the control group) and increased the proportion of surviving animals during reperfusion (86% vs. 42%). The proarrhythmic effect of almokalant was examined during alpha1-adrenoceptor stimulation in chloralose-anaesthetised rabbits. Almokalant (75 nmol/kg per min) triggered torsade de pointes arrhythmias in 8 animals out of 11. The dose of almokalant (mean+/-S.E.M.) required to produce this effect was 1181+/-519 nmol/kg. It is concluded that, although almokalant is an effective antiarrhythmic agent against ischaemia-reperfusion induced arrhythmias, it has marked proarrhythmic activity during alpha1-adrenoceptor stimulation.     

Low-grade gastric MALT lymphoma and helicobacter heilmannii (Gastrospirillum hominis

We report the fourth case of low-grade gastric MALT lymphoma associated to Helicobacter heilmannii. This spiral organism may be present in the gastric mucosa of animals where it is non pathogenic while, in humans, its presence is always associated with chronic gastritis. In this case, Helicobacter heilmannii was observed in the absence of Helicobacter pylori. Regression of endoscopic and histological lesions after Helicobacter heilmannii eradication suggests its role in gastric lymphoma. This observation underlines the need for searching for Helicobacter heilmannii by careful histological examination, in the absence of Helicobacter pylori, and the importance of its eradication in the treatment of gastric lymphoma.     

功率半导体封装技术的发展趋势

每一代新型电子应用都要求电源管理系统有更高的性能.在信息技术和便携式产品市场上,这一趋势尤为明显.直到最近,硅技术一直都是改进电源管理系统性能的最重要因素.然而,硅技术的进步现在受到封装性能提高的限制.为了实现明显的改进,必须提高功率半导体封装技术.下面将对功率封装技术改进的3种途径进行讨论.……     

Prevalence study of oral white lesions with special reference to a new definition of oral leucoplakia

In this survey, the experiences with and implications of a revised definition of oral leucoplakia are described. One of the new aspects of the revised definition is the distinction between a provisional, clinical diagnosis and a definitive one for which histopathological examination is required. A prevalence study of white lesions of the oral mucosa among a selected population of 1000 consecutive patients from the Netherlands showed a prevalence of a provisional and definitive diagnosis of oral leucoplakia of 0.6 and 0.2%, respectively. For uniform reporting, a recently proposed classification and staging system has been used to stage leucoplakias with a definitive diagnosis. The use of the revised definition of oral leucoplakia, as well as the classification and staging system, seem very suitable for epidemiological studies.