北山 丈二

Polyamines are important to the survival and activation of organs and tissues via a homeostatic cell-metabolic process, and the polyamine content in cytoplasm decreases with aging. Decreases in cellular polyamine have been known to augment mutagenesis and cell death. Thus, supplementary polyamine in food is important to the prevention of aging. Here we show the anti-aging effects of oral intake of polyamine using luciferase-transgenic rats. Healthy rats, 10-12 weeks old, were given foods containing 0.01% and 0.1% (w/w) of polyamine, as compared a control food without polyamine, for 4 weeks. Using a bioimaging system, the photon intensities seen in the whole bodies and livers of rats consuming 0.1% of polyamine in food were stronger than those in rats consuming 0.01% and 0% of polyamine. However, there were no differences between groups in other characteristics, such as liver damage and body weight. In conclusion, we found that polyamine intake can activate cells throughout the whole body, providing an anti-aging effect.

BACKGROUND/AIMS: Recent studies have demonstrated that the populations of several microbes are significantly increased in fecal samples from patients with colorectal cancer (CRC), suggesting their involvement in the development of CRC. The aim of this study was to identify microbes which are increased in distal CRCs and to identify the specific location of microbes increased in mucosal tissue around the tumor. METHODS: Tissue specimens were collected from surgical resections of 28 distal CRCs. Five samples were collected from each specimen (location A: tumor, B: adjacent normal mucosa, C: normal mucosa 1 cm proximal to the tumor, D: normal mucosa 3 cm proximally, and E: normal mucosa 6 cm proximally). The microbiota in the sample were analyzed using 16S rRNA gene amplicon sequencing and the relative abundance (RA) of microbiota compared among the 5 locations. RESULTS: At the genus level, the RA of Fusobacterium and Streptococcus at location A was the highest among the 5 locations, significantly different from that in location E. The dominant species of each genus was Fusobacterium nucleatum and Streptococcus anginosus. The RAs of these species gradually decreased from locations B to E with a statistically significant difference in F. nucleatum. The genus Peptostreptococcus also showed a similar trend, and the RA of Peptostreptococcus stomatis in location A was significantly associated with depth of tumor invasion and tumor size. CONCLUSION: Although the clinical relevance is not clear yet, these results suggest that F. nucleatum, S. anginosus, and P. stomatis can spread to the adjacent normal tissues and may change the surrounding microenvironment to support the progression of CRC.

症例は48歳の男性で,約1ヵ月前に左手外傷に対して鼠径部より採皮,植皮術を施行され,退院後より腹部違和感を自覚していた.腹部症状が増悪し意識障害も出現したため前医を受診し,造影CTで広範な門脈血栓症を認め,入院となった.翌日,下部消化管出血を認め,当院転院となった.転院時造影CTで上腸間膜静脈血栓症と診断された.小腸壊死は明らかでなく,抗凝固療法を開始し,約40日の経過で血栓はほぼ消失した.経口摂取開始後に嘔吐が出現したため,小腸造影および小腸3D-CTを撮影したところ上部空腸の器質的狭窄を認めた.転院後第59病日に小腸部分切除術を施行した.病理学的には血栓形成を伴う虚血性腸炎の診断であった.術後20日目に退院し,現在も再発は認めていない.本症例では,3D-CTが遅発性小腸狭窄の範囲の推定と切除範囲の決定に有用であった.(著者抄録)

症例は48歳の男性で,約1ヵ月前に左手外傷に対して鼠径部より採皮,植皮術を施行され,退院後より腹部違和感を自覚していた.腹部症状が増悪し意識障害も出現したため前医を受診し,造影CTで広範な門脈血栓症を認め,入院となった.翌日,下部消化管出血を認め,当院転院となった.転院時造影CTで上腸間膜静脈血栓症と診断された.小腸壊死は明らかでなく,抗凝固療法を開始し,約40日の経過で血栓はほぼ消失した.経口摂取開始後に嘔吐が出現したため,小腸造影および小腸3D-CTを撮影したところ上部空腸の器質的狭窄を認めた.転院後第59病日に小腸部分切除術を施行した.病理学的には血栓形成を伴う虚血性腸炎の診断であった.術後20日目に退院し,現在も再発は認めていない.本症例では,3D-CTが遅発性小腸狭窄の範囲の推定と切除範囲の決定に有用であった.(著者抄録)

BACKGROUND: Leiomyosarcoma is a rare tumor that could originate from the gastrointestinal tract, uterus, kidney, retroperitoneum, and the soft tissues of the extremities. It accounts for only 1% of all gastrointestinal mesenchymal tumors and primary leiomyosarcoma of the stomach is extremely rare. Most cases reported as leiomyosarcoma of the stomach before the development of KIT immunohistochemistry might be gastrointestinal stromal tumors (GISTs) of the stomach and only 18 cases of leiomyosarcoma of the stomach have been reported since early 2000s. We report here a patient with leiomyosarcoma of the stomach treated by laparoscopic and endoscopic cooperative surgery (LECS). CASE PRESENTATION: A 59-year-old man was referred to our hospital for an early gastric cancer, which was initially treated by endoscopic submucosal dissection. Six months after his initial treatment, a follow-up esophagogastroduodenoscopy revealed a small polypoid lesion at the lesser curvature of the proximal stomach, which appeared to be a hyperplastic polyp. However, one and a half years later, the lesion grew and showed more irregular surface. Biopsy at the time revealed smooth muscle cell proliferation suggestive of leiomyoma. Three years later, the lesion grew even larger and biopsy showed pleomorphic spindle cells. Immunohistochemical study showed positive staining for alpha-smooth muscle actin and desmin, but negative for c-kit and CD34. Ki-67 labeling index was nearly 60%. Based on these findings, the diagnosis of leiomyosarcoma was established. The patient subsequently underwent a partial gastrectomy by LECS. The patient is currently in good condition without recurrence or metastasis at 12 months after surgery. CONCLUSIONS: Leiomyosarcoma of the stomach is extremely rare. This is the first report of leiomyosarcoma of the stomach treated by LECS. We could also follow its appearance change through endoscopic examination for 3 years.

Background: Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal malignancies globally. We have previously explored the clinical efficacy of intraperitoneal (IP) paclitaxel therapy for patients with PDAC and peritoneal metastasis, which demonstrated favourable response and disease control rates. However, the real implications of conversion surgery after IP therapy remain unclear. Methods: We conducted two multicenter clinical trials of IP therapy with paclitaxel in patients with PDAC and peritoneal metastasis. We focused on patients who underwent conversion surgery and investigated the long-term outcomes, particularly, initial recurrence patterns and long-term survival. Results: Seventy-nine patients with PDAC and peritoneal metastasis were treated, and 33 (41.8%) patients received SP (intravenous IP paclitaxel with S-1) and 46 (58.3%) were administered GAP (intravenous gemcitabine + nab-paclitaxel combined with IP paclitaxel) combination therapy. Of the 79 patients, 16 (20.3%) underwent conversion surgery. The median time to surgery was 9.0 (range, 4.1-13.0) months after the initiation of chemotherapy. Finally, 13 (81.3%) patients underwent R0 resection. Evans grade was IIA in nine patients, IIB in four patients, III in two patients, and IV in one patient. The median overall survival time in patients who underwent conversion surgery was 32.5 (range, 13.5-66.9) months. Twelve (75.0%) patients were found to have experienced recurrence after conversion surgery. Especially, peritoneal recurrence was observed in 50% of patients as the initial recurrence pattern. The median recurrence-free survival time was 9.2 (range, 5.1-32.8) months, and three patients have survived without recurrence to date. Conclusions: Our IP therapy displays promising clinical efficacy with acceptable tolerability in patients with PDAC and peritoneal metastasis. Although we could observe some super-responders in the cohort, further improvements in IP therapy are warranted.