Biomedical subjects

Tomohiko Osaragi

Publications and source records attributed to Tomohiko Osaragi.

4 recordsLinked to original sources

PubMed2006

Transintestinal systemic oxygenation using perfluorocarbon.

PURPOSE: Perfluorocarbons have an excellent oxygen- and carbon dioxide-carrying capacity. This prompted us to investigate the feasibility of transintestinal systemic oxygenation using perfluorocarbon. METHODS: A rat hypoventilation model (room air, 20 breaths/min and a tidal volume of 10 ml/kg) was thus established, and FC-77 (Sumitomo-3M, Osaka, Japan) was used as a perfusate. Oxygenated FC-77 was perfused through the small intestine for 4 h. The rats were allocated into three groups as follows. Group 1 (n = 6): hypoventilation only; Group 2 (n = 6): saline was perfused instead of FC-77; Group 3 (n = 6): FC-77 was perfused. Arterial blood samples were drawn from the common iliac artery every 30 min until the end of perfusion. A standard blood gas analysis was performed. RESULTS: The PaO2 level in Group 3 was significantly higher than in Groups 1 or 2 (P = 0.006: at the end of perfusion, Group 1 = 58.6 +/- 14.5 mmHg, Group 2 = 65.2 +/- 29.4 mmHg, Group 3 = 84.0 +/- 35.5 mmHg). The PaCO2 level in Group 3 was significantly lower than that in Groups 1 or 2 (P = 0.014: at the end of perfusion, Group 1 = 56.8 +/- 8.5 mmHg, Group 2 = 52.6 +/- 5.7 mmHg, Group 3 = 44.4 +/- 11.1 mmHg). CONCLUSION: Our findings indicate that transintestinal systemic oxygenation is indeed possible and could therefore become a useful new modality for respiratory assist.

Animals↗

PubMed2006

The efficacy of gastrectomy for large gastric cancer.

BACKGROUND: Large gastric cancer (LGC) is frequently associated with extended disease, and the role of surgical resection has been debated. We investigated the efficacy of surgical treatment for LGC. METHODS: The size of LGC was defined as 8 cm or greater. Four hundred and fifteen patients with LGC who underwent gastrectomy were included. The clinicopathological features, the status of the residual tumor, the incidence and patterns of relapse, and the survival were analyzed. RESULTS: Macroscopically, diffuse-type tumors were dominant (60%). The numbers of patients with tumors of T3 or greater, lymph node involvement, and peritoneal metastases were 356 (86%), 359 (87%), and 126 (30%), respectively. One hundred and eighty-eight patients (45%) underwent incomplete tumor resection (R2). The R2/R0 (no residual tumor) ratio was greater than 1 in patients with type 4 tumors and N1 or greater metastasis and in those with type 3 tumors and N2 or greater metastasis. In contrast, T2, type 2, and type 5 tumors were more likely to be completely resected. The 5-year survival for all 415 patients was 26%. The survival rates were inversely related to the tumor type, size, and lymph node metastasis. In the 216 patients with R0, the 5-year survivals of those with pN (International Union Against Cancer [UICC] classification) 0, 1, 2, and 3 were 66%, 56%, 36%, and 5%, respectively (P = 0.001). In 96 of these 216 patients (44%) the tumor recurred, and peritoneal metastasis was the most frequent mode of recurrence (48%). By Cox's proportional hazard model, the tumor size was an independent prognostic factor. CONCLUSION: The chance of achieving R0 resection for LGC is low, except for T2, type 2, or type 5 tumors. Primary resection should be avoided for other types of LGC.

Gastrectomy↗

PubMed2005

A subacute hypoxic model using a pig.

PURPOSE: A large animal model of hypoxia is necessary to develop a new therapeutic method for respiratory failure. METHODS: The experiments were performed on six pigs weighing from 15 to 19 kg. Under general anesthesia the left chest was opened and the left main bronchus was closed by a stapler. A Swan-Ganz catheter was inserted through the right jugular vein. The right carotid artery was cannulated and the mean arterial blood pressure was monitored, and arterial blood samples were drawn every 24 h until 96 h after the operation. The blood samples were submitted for a blood gas analysis. All data were expressed as the mean +/- standard deviation of the mean. RESULTS: The partial pressure of the oxygen of the arterial blood at baseline (104.8 +/- 24.3 mmHg) significantly decreased at 24 h after closure of the bronchus (76.7 +/- 9.9 mmHg, P < 0.001) and thereafter remained at the same level for 4 days. CONCLUSION: This hypoxic model using a pig was found to be very simple, effective, and reproducible. This model can be used for a variety of experiments to evaluate new therapeutic modalities for respiratory failure.

Animals↗

PubMedDate not supplied

Feasibility study of biweekly CPT-11 plus CDDP for S-1- and paclitaxel-refractory, metastatic gastric cancer.

BACKGROUND: To confirm the feasibility and efficacy of biweekly irinotecan (CPT-11) plus cisplatin (CDDP) as third-line chemotherapy, the response rate (RR), overall survival and toxicity were evaluated in patients who had been treated with S-1 as a first-line and paclitaxel as a second-line chemotherapy for metastatic gastric cancer. PATIENTS AND METHODS: The eligibility criteria of our study were: i) pathologically-confirmed adenocarcinoma of the stomach, ii) primary non-resectable or recurrent tumors, iii) Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 2 or less, iv) age less than 75 years, v) adequate hepatic, renal and bone marrow functions and vi) patients had received S-1 as a first-line and paclitaxel as a second-line chemotherapy and both regimens had failed. The treatment consisted of CPT-11 (60 mg/m2) and CDDP (30 mg/m2) on day 1 and day 15, repeated every 4 weeks. RESULTS: Twenty-six patients were enrolled in this study. All the treatment was administered at the out-patient clinic except the first course for the initial 4 patients. The overall RR was 23.1% in all and 30.0% in the patients with target tumors (6 partial response, 11 stable disease, 7 progressive disease, 2 non-evaluable). Overall grade 3/4 toxicity was observed in 5 patients (19.2%) including pancytopenia, neutropenia, anemia, anorexia and elevation of AST/ALT. The time-to-treatment failure and the median survival time were 95 and 299 days, respectively. CONCLUSION: Biweekly CPT-11 plus CDDP was feasible for S-1- and paclitaxel-refractory metastatic gastric cancer, with moderate activity and favorable toxicity. This regimen was safely performed at the out-patient clinic as third-line chemotherapy.

Adenocarcinoma↗