[Treatment strategy for malignant solid tumors in childhood].

The prognosis for children with malignant solid tumors has improved dramatically in Japan. During the last two decades, various groups have conducted sequential studies of the treatment of children with neuroblastoma, Wilms' tumor, and hepatoblastoma. Most institutes participated in nonrandomized trials designed to evaluate the safety and efficacy of combination chemotherapy, surgery, and radiotherapy in each group study and treated children with these tumors The results are reviewed and areas for future investigation are identified.

[Molecular epidemiological investigation of vero toxin-producing Escherichia coli (VTEC) isolated from diarrhea patients and dairy cattle].

To elucidate the source and route of VTEC infection, we performed pulse field gel electrophoresis (PFGE) an 50 isolates from human diarrhea typed as serotypes O157, O111, and O26, which were very frequently isolated from patients with VTEC infection between 1986 and 1997, and 32 isolates from dairy cattle, a total of 82 isolates. The isolates were genetically analyzed based on the electrophoresis patterns of DNA, and a phylogenetic tree was prepared. The isolates were classified based on similarity > or = 89. The following results of the molecular epidemiological investigation were obtained. 1) Based on the electrophoresis patterns of DNA obtained by PFGE, 34 of the 49 O157 isolates (69.4%) were divided into groups 1-9, 15 of the 18 O111 isolates (83.3%) were divided into groups 1-3, and 12 of the 15 O26 isolates (80%) were divided into groups 1-3. Of the grouped isolates, group 8 of O157, groups 2 and 3 of O111, and group 3 of O26 included isolates from human diarrhea and dairy cattle, but the other groups included isolates from only one of the two sources. 2) With regard to regional investigation, groups 6 and 9 of O157 included human diarrhea-derived isolates from Yokohama and Ehime, and group 8 included a human diarrhea-derived isolate from Yokohama and a dairy cattle-derived isolate from Tokushima. Group 3 of O111 included a human diarrhea-derived isolate from Ehime and a dairy cattle-derived isolate from Hokkaido. Group 3 of O26 included human diarrhea-derived isolate from Ehime and dairy cattle-derived isolate from Sagamihara and Hokkaido. Since the above findings showed that although the frequency was low, isolates from human diarrhea and dairy cattle were included in the same groups, it was demonstrated that dairy cattle are closely related to the human infectious disease of the intestinal tract as a source of infection. However, classification using the PFGE method is difficult due to diversity of the electrophoresis pattern of DNA. It is necessary to investigate the classification by a combination of the PFGE method with phage typing, ribotyping, and RAPD-PCR, and to investigate more numbers of patient-derived and animal-derived isolates.

Endosonographic evaluation in two children with esophageal stenosis.

The authors report the successful use of endoscopic ultrasonography (EUS) for finding the etiology and subsequent treatment strategy for esophageal stenosis in 2 children. In case 1, EUS showed anterior wall thickening and multiple low echoic regions in the mp layer. These regions were believed to be cartilage. Esophageal resection therefore was performed. In case 2, EUS showed disruption of the sm and mp layers at the stenosis, leading us to speculate that the stenosis was caused by gastroesophageal reflux. After balloon dilatation, he underwent antireflux surgery of Nissen's fundoplication. EUS was useful for determining the etiology of esophageal stenosis and, thus, the appropriate treatment strategy.