Effects of methylxanthine derivatives on antitumor activity and toxic side effect of adriamycin induced by inhibition of DNA biosynthesis

The antitumor activity of adriamycin (ADR) was enhanced by combination with theobromine or pentoxifylline. Theobromine increased the concentration of ADR in the tumor without any effects on that in the heart and the liver. The influence of the combination of theobromine or pentoxifylline with ADR on the lipid peroxide level (indicating the ADR-induced side effect) and on DNA biosynthesis (indicating the side effect and antitumor activity) were examined. When ADR was administered into mice, the lipid peroxide level in the liver and the heart increased. However, the combination of theobromine or pentoxifylline did not enhance the ADR-induced increment of the lipid peroxide level in the liver, and moreover, it inhibited that in the heart. The decrease of DNA biosynthesis in the liver and the heart, induced by ADR, were not enhanced by combination with theobromine or pentoxifylline. On the other hand, the combination of theobromine with ADR significantly increased the inhibition of DNA biosynthesis in the tumor. These findings indicate that the combination of theobromine or pentoxifylline with ADR have no effect on the side effects of ADR in the liver and the heart, with the increase of antitumor activity of ADR in the tumor, and it is suggested that these drugs will be of value as a biochemical modulator of ADR.     

Fuzzy system identification via probabilistic sets

The paper deals with the applications of probabilistic sets in system theory, especially in system identification and the design of fuzzy logic controllers. Fuzzy systems described by means of fuzzy relational equations and Λ-fuzzy systems are discussed. The identification procedure is based on some ideas of clustering techniques and probabilistic sets. Numerical examples using fuzzy and nonfuzzy data are used to illustrate the theory.     

Wilms' tumor suppressor gene (WT1) as a target gene of SRY function in a mouse ES cell line transfected with SRY

With the aim of identifying the gene(s) located downstream from SRY, we transfected an ES cell line with XX karyotype, TMA-18, with a Sry DNA construct and established cell lines, TS18-1 and TS18-2, where the transfected Sry was expressed in the functional linear mRNA form. Among the five potential SRY-target genes examined, i.e., MIS, SF1, P450arom, Sox9 and WT1, only the expression of WT1 was induced de novo by the unscheduled expression of Sry in the transfected cell lines. No clear indication of Sry-induced enhancement of Sox9 expression was obtained in the present series of experiments. Function of a yet unidentified gene(s) located on the Y chromosome might be needed for the up-regulation of Sox 9 expression which takes place during the development of male gonads. Quantitative RT-PCR analysis of the patterns of WT1 expression in developing fetal gonads revealed that although both male and female fetal gonads express WT1, male gonads invariably expressed WT1 mRNA at higher levels than female ones after the Sry expression. Immunohistochemical analysis of the male fetal gonads between 10.5 and 13.5 dpc demonstrated the presence of strong WT1 immunoreactivity in Sertoli cells of the primordial testes. Suggestions were made in the past indicating that both SF1 and WT1 proteins might be active in a common pathway upstream from Sry. Our results showed that WT1 is located downstream, rather than upstream from Sry and behaves independently from SF1. Analysis using an appropriate in vitro system will be essential to understand the molecular mechanisms of SRY action within cells.     

Irrigation

This paper provides an overview of the main features of irrigation in Japan, and the issues it raises, rather than an exhaustive survey of the subject. The authors’ remarks concentrate on irrigation for rice cultivation, since irrigation for non‐paddy crops is not widely developed and claims a very minor share of the country's water resources. The main components of the water requirements of rice irrigation are identified, and then the composition and functions of farmers’ irrigation associations, or more correctly ‘land improvement districts’, are described.     

Esophageal intramural metastasis from an adenocarcinoma of the gastric cardia: report of a case

We report herein the rare case of a 65-year-old man found to have esophageal intramural metastasis from cancer of the gastric cardia. Endoscopic examination initially revealed an infiltrating ulcerative tumor of the gastric cardia involving the esophagogastric junction, as well as a submucosal tumor of the lower esophagus. A total thoracic esophagogastrectomy with lower mediastinal lymphadenectomy was performed, and the resected specimen demonstrated that both the cardia and esophageal tumors were adenocarcinomas with the same cellular differentiation. As lymphatic invasion and metastases to the paracardial and mediastinal lymph nodes were observed, the esophageal submucosal tumor was considered to be an intramural metastasis from the carcinoma of the gastric cardia resulting from extensive lymphatic spread. The patient died of recurrent disease 9 months after the resection. This case report serves to demonstrate that intramural metastasis may be a local indicator of the systemic spread of disease in patients with gastric carcinoma, as it is in esophageal carcinoma.     

Hemizygous deletion of the HPC-1/syntaxin 1A gene (STX1A) in patients with Williams syndrome

HPC-1/syntaxin 1A is a membrane protein that plays an important role in exocytosis of neurotransmitters from neuronal cells. We previously mapped the human HPC-1/syntaxin 1A gene (STX1A) to chromosome 7q11.2, which is within the Williams syndrome (WS) region. Here, we performed FISH analysis on 46 patients with WS to examine the relationship between STX1A and WS. Our results showed a hemizygous deletion of the HPC-1/syntaxin 1A gene in each patient, suggesting that the neurological symptoms of WS may be related to the hemizygous deletion of STX1A.     

Low-Temperature Sintering of Mullite/Yttria-Doped Zirconia Composites in the Mullite-Rich Region

Mullite/Y-TZP composites in the mullite-rich region, using powders of mullite prepared via the hydrazine method and a commercially available zirconia compound (ZrO₂(2Y)), have been fabricated by sintering for 3 h at 1450°C in air. The grain sizes of mullite and ZrO₂(2Y) are changed with increased ZrO₂(2Y) content; the former decreases from 0.25 µm to 0.13 µm, and the latter increases from 0.21 µm to 0.35 µm. High strength (780 MPa) and fracture toughness (5.4 MPam^1/2) are obtained in the 50/50 (vol%) mullite/ZrO₂(2Y) composite with 99.6% of theoretical density.     

Flow structure and heat transfer mechanism of laminar vortex rolls driven by gravity currents between parallel plates of nonuniform wall temperature

Laminar vortex rolls which occur between horizontal parallel plates, of which the temperature is not uniform in the lateral direction normal to the forced main flow, are investigated by means of a flow-visualization technique and a 3D steady-state numerical calculation. It was found that the vortex rolls were driven by the horizontal gravity currents, which were caused by density difference in the lateral direction, and that the generation mechanism of the vortex rolls could be classified into four types. The effects of vortex rolls on the local Nusselt number were also investigated. © 1999 Scripta Technica, Heat Trans Asian Res, 28(7): 606–619, 1999