The persistence of leptospiral agglutinins titers in human sera diagnosed by the microscopic agglutination test

Human serum albumin (HSA) is used in large amounts as an excipient in many biopharmaceutical formulation to prevent loss of the active ingredient through adsorption and/or degradation. Traditionally, iso-electric focusing has been used to demonstrate charge heterogeneity in HSA preparations. In an effort to develop new methods for the analysis of formulation components, a capillary zone electrophoresis method was developed for the analysis of HSA. Under initial separation conditions using untreated silica capillaries and 20 mM sodium phosphate, pH 6.0 as electrophoretic buffer, HSA migrated as a single peak. Addition of 1,4-diaminobutane allowed separation of several components which could be further resolved by varying the buffer pH. Optimal separation conditions were attained at 5 mM 1,4-diaminobutane and pH 8.5. The reproducibility of the separation conditions was verified by using capillaries from a different manufacturer. A comparative analysis of HSA preparations from different manufacturers provided evidence that the method may be used to qualitatively differentiate individual preparations. The analysis of rhEPO formulations, composed largely of HSA, showed levels of heterogeneity comparable to that of HSA preparations. Electrospray ionisation mass spectrometry (ESA-MS) was used as an independent method to confirm the heterogeneous nature of HSA.     

Intraarterial chemotherapy via reservoir system for far-advanced bladder and prostate cancer

A clinical study was performed on the efficacy of intraarterial chemotherapy using reservoir system for far-advanced urological malignancy. The reservoir system was indwelled in the femoral subcutaneous layer using Seldinger's method. Fifteen cases with inoperable complicated advanced bladder cancer and ten cases with postoperative local recurrent bladder cancer received intraarterial chemotherapy using the reservoir system. Then, 23 cases with local relapsed prostate cancer and two cases with endocrine-resistant prostate cancer received chemotherapy. The administered anti-cancerous agents were methotrexate, cis-platinum and adriamycin, and 5-FU or carboplatin were administered as maintenance therapy. The mean courses of chemotherapy were six for bladder cancer and four for prostate cancer. During stabilization of the local lesion, no distant deterioration was recognized. Overall clinical efficacy was as follows: PR:18 cases and NC:7 cases for bladder cancer; then, PR:11 cases and 14 cases for prostate cancer. The median duration of stabilization was as follows: 23 months for bladder cancer and 12 months for prostate cancer. Complications were fewer than with systemic chemotherapy.     

Shear strength of C/C composites containing an inorganic compound effective for anti-oxidation

Abstracts are not published in this journal This revised version was published online in November 2006 with corrections to the Cover Date.     

Detection of isozymes of deoxyribonucleases I and II on electrophoresed gels with picogram sensitivity using SYBR Green I

A highly sensitive method for detecting deoxyribonucleases (DNases) I and II on an electrophoresed gel is described. A dried agarose film sheet containing DNA as a substrate and a buffer reagent was placed in contact with the gel surface after electrophoresis (DAFO method, Yasuda et al., Anal. Biochem. 1989, 183, 84-88). After an appropriate incubation period, the film sheet was peeled off and stained with SYBR-Green I (SG), and then the DNase isozyme bands were detected using a fluorescence image analyzer. We could detect pg levels of the DNases (DNase I, 2 pg; DNase II, 2pg), which represents a 32- to 128-fold increase in sensitivity compared with the original DAFO method using ethidium bromide (EB) as the fluorescent dye. A combination of this new detection method and isoelectric focusing electrophoresis in polyacrylamide gel allowed accurate DNase I typing from 1 microL human serum. This new technique has been named SG-DAFO, after its original dried agarose film overlay method using EB (EB-DAFO).     

Structure and properties of highly crystallized graphite films based on polyimide Kapton

Highly crystallized graphite films were prepared by heat treatment of carbonized polyimide films (Kapton) at temperatures of 2700 and 3050° C. Interlayer spacing d ₀₀₂ at room temperature, and electrical resistivity, magnetoresistance and Hall coefficient at room and liquid nitrogen temperatures were measured. All of these data indicate high crystallinity of the graphitized Kapton films obtained. For the graphite films heat treated at 3050° C mean-square mobilities were estimated from the magnetoresistance data at 1 T to be 0.91 m² V^–1 sec^–1 at room temperature and 2.3 m² V^–1 sec^–1 at liquid nitrogen temperature; the value at liquid nitrogen temperature corresponds to that for a pyrolytic graphite heat treated at 3200° C for 1 h (PG 3200). Magnetic field dependence of Hall coefficient at liquid nitrogen temperature for this sample also agrees well with that for PG 3200. Scanning electron micrographs on the surfaces show that the present graphite films consist of grains of large crystallites, and grain size increases as the crystallinity of the material improves.     

Age-hardening and the associated phase transformation in an Au-55.2 at% Cu-17.4 at% Ag ternary alloy

To develop a low gold content dental alloy, age-hardening characteristics in an Au-55.2 at% Cu-17.4 at% Ag alloy were studied by means of hardness, electron microscopy and X-ray diffraction examination. Three distinct age-hardening behaviours depending on temperature were found in the alloy, i.e. (i) a dual mechanism of spinodal decomposition and Cu₃Au ordering below 673 K, (ii) a single mechanism of spinodal decomposition at 693 K, and (iii) a single mechanism of nucleation and growth of silver-rich precipitate at 773 K. A marked over-ageing was observed by lengthy ageing over the whole range of temperature. The long-period superstructure of Cu₃Au(II) was found only in the grain boundary product at temperatures between 623 and 633 K.     

A questionnaire study on improving occupational safety and health services provided by part-time industrial physicians

In order to evaluate factors improving part-time industrial physicians' services, a questionnaire study on occupational safety and health services was conducted on 237 part-time industrial physicians (PIPs) and 628 enterprises in Kochi. PIPs who received physician's fees visited enterprises and consulted with employees about their health conditions, communicated with employers and licensed occupational health supervisors (LOHSs) in enterprises more frequently than PIPs who did not receive physician's fees (p < 0.1-0.001). The rates of performing regular duties related on occupational safety and health, and PIPs' participations in health promotion programs and health consultations with employees among enterprises which paid physician's fees were significantly higher than those among enterprises which did not pay physician's fees (p < 0.05-0.001). Significantly higher rates of health consultation with employees and communications with employers and LOHSs, participation in occupational safety and health committees, recommendations of health promotion programs were found where physicians visited enterprises frequently(p < 0.1-0.01). Although no significant changes in PIPs' occupational safety and health services were observed for hazardous risk factors in enterprises, the rates of performing regular duties on occupational safety and health, and walk-through inspections by LOHSs and PIPs, estimating PIPs' advice and suggestions in enterprises with hazardous risk factors were significantly higher than those in enterprises without hazardous risk factors (p < 0.05-0.001). It is important for PIPs to have a written contract concerning physicians' fees and occupational safety and health services with enterprises and visit enterprises frequently in order to improve PIPs' occupational safety and health services and promote occupational safety and health programs in enterprises.     

A mutation in succinate dehydrogenase cytochrome b causes oxidative stress and ageing in nematodes

Much attention has focused on the aetiology of oxidative damage in cellular and organismal ageing. Especially toxic are the reactive oxygen byproducts of respiration and other biological processes. A mev-1(kn1) mutant of Caenorhabditis elegans has been found to be hypersensitive to raised oxygen concentrations. Unlike the wild type, its lifespan decreases dramatically as oxygen concentrations are increased from 1 to 60%. Strains bearing this mutation accumulate markers of ageing (such as fluorescent materials and protein carbonyls) faster than the wild type. We show here that mev-1 encodes a subunit of the enzyme succinate dehydrogenase cytochrome b, which is a component of complex II of the mitochondrial electron transport chain. We found that the ability of complex II to catalyse electron transport from succinate to ubiquinone is compromised in mev-1 animals. This may cause an indirect increase in superoxide levels, which in turn leads to oxygen hypersensitivity and premature ageing. Our results indicate that mev-1 governs the rate of ageing by modulating the cellular response to oxidative stress.