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The instability of microsatellite sequences dispersed in the genome has been linked to a deficiency in cellular mismatch repair. This phenotype has been frequently observed in various human neoplasms and is regarded as a major factor in tumorigenesis. To demonstrate alterations in microsatellite sequences, polymerase chain reaction (PCR) and electrophoretic analysis are techniques often used. However, the electrophoretic profiles of PCR-amplified microsatellite sequences have not been well characterized. Moreover, the conventional method using autoradiography has critical problems in detection characteristics and migration accuracy. We made use of fluorescence-labeled PCR and laser scanning with linear detection characteristics, so as to detect bands quantitatively. Next, we characterized Taq polymerase-dependent modification of the amplified microsatellite sequences, using artificially synthesized microsatellite alleles and we optimized the electrophoretic profiles by enzymatic modification with T4 DNA polymerase. We developed a dual fluorescence co-electrophoresis system, in which both samples derived from cancer and normal tissues are electrophoresed in the same lane, in order to minimize migration errors. These improvements remarkably facilitate precise and objective assessments of microsatellite instability. Analyzing many positive cases in cell lines and tissue specimens, we classified all the patterns of microsatellite alteration and set up new criteria for assessing microsatellite instability.

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The incidence of gastric cancer is much higher in Japan than in other countries even though diagnostics and treatments of such patients have improved. The objective of this study was to present an overview of the past, present and future of surgical treatment for our patients with gastric cancer. We analysed data on 2152 Japanese men and women with gastric cancer who underwent surgical resection from 1965 to 1995 at Kyushu University in Fukuoka, Japan, based on a univariate and the multivariate analysis. We focused on time trends of surgical treatment and the postoperative outcome. Over the years, there have been favourable changes in the numbers of patients with early gastric cancer. In all cases of gastric cancer, the rate of 18% in the first six year period (group 1) was 57% in the last 5 year period (group 6). Size of the tumour was smaller, well-differentiated tumour tissue was more common, and lymphatic involvement was less frequent. Lymph node metastasis, liver metastasis and peritoneal dissemination all decreased. Extensive lymph node dissection was more frequently done and the rate of curative resection (curability A and B) increased. With increases in identifying the early stage of cancer and better perioperative care, mortality rates 30 days after the surgery greatly decreased. Multivariate analysis revealed that the 10 factors of depth of invasion, lymph node metastasis, lymph node dissection, tumour size, liver metastasis, peritoneal dissemination, lymphatic invasion, vascular invasion, lesion in the whole stomach and lesion in the middle stomach were independent factors for determining the prognosis. Detection of the tumour in an early stage, standardized surgical treatment, including routine lymph node dissection, close follow-up schedules and better perioperative management are expected to increase survival time for patients with this malignancy. © 2000 Cancer Research Campaign

Depressed heart rate variability (HRV) in septic patients is known to be associated with poor outcome. However, neither etiology of depression of HRV nor its clinical significance has been clearly determined. Because hypercytokinemia plays an important role in sepsis, we investigated the relationships between depressed HRV and IL-6 blood level. The subjects of this study were 45 septic patients treated in our intensive care unit. IL-6 blood level upon admission exhibited significant negative correlations with two HRV indices, low-frequency power (LF) (r = -0.76; P < 0.01) and high-frequency power (HF) (r = -0.53; P < 0.01). Multivariate analysis revealed strong correlations between IL-6 blood level and LF (P = 0.01) and HF (P = 0.01), respectively, even when the effects of patient background factors and therapeutic intervention were taken into account. Among the patients who developed septic shock, a high IL-6 blood level and a low LF were observed in both the survivor and nonsurvivor groups on the day of admission. The HF was lower than normal at the same time points in both groups. However, the HF was significantly higher in the nonsurvivor group than in the survivor group. By the time of discharge from the intensive care unit, both IL-6 blood level and HRV indices had become significantly closer to the normal ranges in the survivor group, but not in the nonsurvivor group. A significant negative correlation was observed between LF upon admission and percent decline in blood pressure (r = -0.76, P < 0.01). These findings indicate that reduction in HRV indices is associated with hypercytokinemia, indicating that the autonomic nervous system and the inflammatory response mediated by the cytokine network affect each other. These results also suggest that depression of HRV is closely related to rapid changes in blood pressure. Thus, heart rate variability indices are associated with both the severity and poor outcome of sepsis.