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Notes: Summary Background Pemphigus is an antidesmoglein (Dsg) autoimmune disease that is divided into two major subtypes: pemphigus foliaceus (PF) and pemphigus vulgaris (PV). We previously developed enzyme-linked immunosorbent assays (ELISAs) using recombinant Dsg1 and Dsg3 to detect IgG autoantibodies in patients with pemphigus. The protocol for the ELISAs was optimized for serological diagnosis, but under the conditions used, these assays were not particularly useful for monitoring disease activity in certain patients. That is, the sera from some patients with high-titre antibodies continued to show high index values in the ELISA after clinical improvement. Objectives In the study reported here, we modified the ELISA protocol to obtain ‘true’ index values that exhibit a better correlation with disease activity. Methods We tested two cases of pemphigus foliaceus (PF) and four cases of pemphigus vulgaris (PV), each with ELISA index values greater than 150 for Dsg1 or Dsg3. We ran an ELISA with sera from these patients serially diluted from 1 : 100 to 1 : 12,800. We then performed ELISA with a series of PV No. 1 sera diluted to 1 : 800 and PV No. 2–4 and PF No. 1–2 sera diluted to 1 : 1600, after which we plotted the ELISA index values against the time course of disease activity. Results In each of these cases, there was no apparent decline, over the course of the disease activity, in the ELISA index values at a serum dilution of 1 : 100, probably because the antigen–antibody reaction was saturated at that dilution. After running an ELISA with sera serially diluted from 1 : 100 to 1 : 12,800 we found that a linear dose-dependency between the dilution value and the index value was only observed when sera were diluted to 1 : 800 or more in one case (PV No.1) and to 1 : 1600 or more in the other five cases (PV No. 2–4, PF No. 1–2). After performing ELISA with these series as outlined above we plotted the ELISA index values against the time course of disease activity and found that the index values obtained from these appropriately diluted sera fluctuated in parallel with disease activity, and declined with clinical improvement. Conclusions These findings indicate that when appropriate dilutions are used in Dsg1 and Dsg3 ELISA, these assays can provide useful serological information for assessing disease activity in PF and PV.

Notes: The thermal decomposition kinetics and thermal stability of poly (methyl methacrylate)(PMMA) and PMMA/ montmorillonite (MMT) nanocomposites containing 4 wt% MMT wereresearched by thermogravimetry (TG). The results show that, because of the barrier behavior ofexfoliated MMT layer, the temperature of thermal decomposition of PMMA/ MMT nanocompositesis improved by about 10 °C, and thermal stability is improved by about double. The apparentactivation energy of decomposition, calculated by Ozawa equation, of nanocomposites is higherthan that of PMMA before 27 % mass loss

Notes: Passive film of stainless steels possesses good corrosion resistant property. However, thepassive film formed in nature is not uniform and the quality is not consistent. It is the major causesfor local corrosion. The pitting potential test is a traditional method to test local corrosion ofstainless steels. The local corrosion is usually induced by the break-down of the passive film.Therefore, it can be utilized to evaluate the quality of the passive film. Also, because the pitting testis quick and inexpensive, many tests can be performed to evaluate the uniformity of the passivefilm. This study focuses on SS316 stainless steel. The specimens were treated with electropolishingprocesses. The original and the processed specimens were tested by pitting potential tests. Fromthese results, the distribution and the uniformity of passive film could be evaluated. An efficient andinexpensive index of the uniformity of the passive film is proposed