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N Matsuki

Publications and source records attributed to N Matsuki.

160 records · Page 9Linked to original sources
PubMed1984

[The pathogenesis of diabetes produced by subtotal pancreatectomy, with special reference to the cell kinetics of the islet cells].

The pathogenesis of the diabetes produced by the subtotal pancreatectomy was investigated from the pancreatic endocrine function and the cell kinetics of the islet cells. The authors prepared the following two groups in the rats. The first group was 90% pancreatectomized rats and the second group was the 60% pancreatectomized rats. Most of the 90% pancreatectomized rats developed diabetes twelve weeks after operation. In these diabetic rats the insulin secretion was undetectable during glucose infusion. To the contrary, the relative increase of the glucagon secretion was found during arginine infusion in spite of the hyperglycemia. However, non of the 60% pancreatectomized rats developed diabetes during post-operative course up to 6 months. To investigate the cell kinetics of the islet cells, the 3H-thymidine autoradiography was prepared at several intervals after operation. The results of the thymidine labelling index showed two phase of regeneration. The first phase was observed on three to seven days after pancreatectomy and the second phase was on fourteen to twenty-eight days. After the second phase of regeneration, the degeneration of the B-cells was observed in the 90% pancreatectomized rats. On the ninetieth days after operation the atrophy of the islets and the disturbance of the arrangement of A, B and D cells were observed by the immuno-histochemical studies. Meanwhile, the 60% pancreatectomized rats did not show degeneration of the islets. These results show that the onset of diabetes after subtotal pancreatectomy was produced by degeneration of the B cells surpassing their regenerative capacity.

Animals↗
PubMed1983

Tetrodotoxin-sensitive Na+ channels in isolated single cultured rat myocardial cells.

We studied the existence of tetrodotoxin (TTX)-sensitive fast Na+ channels in isolated single (verified by dye injection) myocardial cells compared with small multiple-cell groups from 1- to 3-day-old rat ventricles in cell culture. For single cells, average values were -63 mV maximum membrane potential, 32 mV overshoot, and 65 V/s maximum rate of rise of the action potentials (+Vmax). These values were comparable to values from groups of multiple (2-10) cells. TTX strongly depressed +Vmax dose dependently, with no difference between single and multiple cells. +Vmax was also decreased by lowering extracellular Na+ concentration but not by D 600 or lowering extracellular Ca2+ concentration. These results suggest that 1) isolated single cells possess TTX-sensitive fast Na+ channels, 2) culturing per se does not alter TTX sensitivity, and 3) TTX sensitivity is not modified by cell density.

Action Potentials↗
PubMed1981

Unaltered membrane properties of arterial muscle in Dahl strain genetic hypertension.

To characterize membrane properties of arterial muscle from Dahl strain hypertensive rats, we measured caudal artery contractile sensitivity to norepinephrine and serotonin, membrane potential at 16 and 37 degrees C, and intracellular potassium, sodium, and chloride content. Dahl salt-resistant (R) strain fed low- or high-salt diets and Dahl salt-sensitive (S) strain fed a low-salt diet remained normotensive. The Dahl S strain on high-salt diets became hypertensive after 4 wk of high salt feeding. There was no significant difference in the norepinephrine or serotonin effective concentration (EC) EC50, EC10, or maximum response between the hypertensive and any of the three normotensive groups. Membrane potential measured at 37 and 16 degrees C and electron-probe analysis of intracellular potassium, sodium, and chloride concentration showed no significant differences between the four groups of animals. These results that arterial muscle membrane mechanisms are not altered in genetically hypertensive Dahl salt-sensitive rats.

Animals↗
PubMedDate not supplied

Neoadjuvant chemotherapy for high-grade advanced gastric cancer.

Fifty-five patients with high-grade advanced gastric cancer in whom the presence of stage IV was confirmed by preoperative diagnostic imaging were treated with PMUE therapy by a combined use of cisplatin (CDDP) 75 mg/m2, mitomycin C (MMC) 10 mg/body, etoposide 150 mg/body, and UFT (a combination of 1-(2-tetrahydrofuryl)-5-fluorouracil and uracil in a molar ratio of 1:4) 400 mg/day. CDDP and MMC was administered intravenously on the first day, followed by etoposide 50 mg/day on the 3rd, 4th, and 5th days. All the patients had measurable lesions that were evaluated by computed tomography scanning before and after the treatments. These patients were allocated randomly to two groups. Of these cases, 29 belonged to the neoadjuvant chemotherapy (NAC) group to whom PMUE therapy was given preoperatively; the remaining 26 patients underwent operation first and received PMUE thereafter (control group). Background factors did not differ significantly between the two groups. The response rate was higher in the NAC group than in the control group (62% in the former versus 35% in the latter). The resectability rates were 79% and 88% in the NAC and control groups, respectively. However, the rate of potentially curable cases was higher in the NAC group than in the control group (38% in the former versus 15% in the latter). Among the nonresection cases, the prognosis was highly unfavorable in both groups. In the resection cases, however, the survival rate was significantly better in the NAC group than in the control group. These results may indicate that in patients with high-grade, advanced gastric cancer initial chemotherapy (neoadjuvant chemotherapy) and then surgery should be considered.

Adenocarcinoma↗
PubMedDate not supplied

Hematologic abnormalities and outcome of 16 cats with myelodysplastic syndromes.

We investigated the hematologic abnormalities and prognoses in 16 cats with myelodysplastic syndromes (MDS). Nonregenerative anemia, thrombocytopenia, and neutropenia were observed in 15, 13, and 4, respectively, of the 16 cats with MDS. Morphologic abnormalities characteristic of MDS included megaloblastoid rubricytes (9 cats), hyposegmentation of neutrophils (7 cats), nuclear abnormality of rubricytes (10 cats) and neutrophils (13 cats), and micromegakaryocytes (10 cats). Disease in these 16 cats was subclassified into refractory anemia (RA; 8 cats), RA with excess of blasts (RAEB; 5 cats), RAEB in transformation (RAEB in T; 1 cat), and chronic myelomonocytic leukemia (CMMoL; 2 cats), according to the human French-American-British (FAB) classification. In the cats in which the clinical outcome was known, 3 of 6 cats with high blast cell count MDS, including RAEB, RAEB in T, and CMMoL, developed acute myeloid leukemia, but only 1 of 8 cats with low blast cell count MDS (RA) developed acute myeloid leukemia. Based on the Dusseldorf scoring system for the prognosis of human MDS, the survival times of the cats showing high scores (> or =3 points) were significantly shorter than those of the cats with low scores (<3 points). The FAB classification and Dusseldorf scoring system were considered to be useful for predicting the prognosis of feline MDS. Furthermore, 15 of the 16 cats with MDS in this study were infected with feline leukemia virus, indicating its possible etiologic role in the pathogenesis of feline MDS.

Anemia↗
PubMedDate not supplied

Operative morbidity and mortality after D2 and D4 extended dissection for advanced gastric cancer: a prospective randomized trial conducted by Asian surgeons.

BACKGROUND/AIMS: A randomized study was performed to evaluate morbidity and mortality after D2 (level 1 and 2 lymphadenectomy) and D4 (D2 plus lymphadenectomy of para-aortic lymph nodes) dissection for advanced gastric cancer. METHODOLOGY: Two hundred and fifty-six patients with advanced gastric adenocarcinoma were enrolled (128 to each group). Patients were randomly allocated into D2 (N = 128) or D4 (N = 128) group. The first and second tiers of lymph nodes are removed in D2 dissection. In D4 gastrectomy, the paraaortic lymph nodes were additionally removed. RESULTS: There was no indication of significant distribution bias with regard to age, sex, T-grade, and N-grade between the two groups. Operation time of D4 gastrectomy (369 +/- 120 min) was significantly longer than that of D2 gastrectomy (273 +/- 1103 min), and blood loss of the D4 group (872 +/- 683 mL) was significantly greater than that of the D2 group 571 +/- 527 mL (P < 0.001). Five (4%) and two (2%) medical complications developed in the D2 and D4 groups, respectively. Surgical complications developed in 28 (22%) and 48 patients (38%) after D2 and D4 gastrectomy. The most common complications were anastomotic leakage, pancreatic fistula, and abdominal abscess. Pancreatic fistula developed in 6 (19%) of 32 patients after D4 plus pancreatosplenectomy, but the incidence of pancreatic fistula after D2 gastrectomy plus pancreatosplenectomy was low (6%, 1/16). Two patients died within 30 days of operation (0.8%, 2/256), and each patient belonged to the D2 and D4 group. CONCLUSIONS: Although there is a significantly higher surgical complication rate in D4 dissection, D4 dissection can be done safely as D2 dissection when performed by well-trained surgeons.

Abdominal Abscess↗
PubMedDate not supplied

Correlation of the histological effects and survival after neoadjuvant chemotherapy on gastric cancer patients.

BACKGROUND/AIMS: The surgical results for patients with stage IV gastric cancer are very poor. This study was performed to clarify the morphologic changes and survival after neoadjuvant chemotherapy for the stage IV gastric cancer patients. MATERIAL AND METHODS: Forty-three patients with stage advanced gastric cancer were treated with preoperative PMUE therapy by a combination use of cisplatin 75 mg/m2, mitomycin C 10 mg/body, etoposide 150 mg/body and UFT 400 mg/day. Among them, 32 patients underwent gastrectomy. Resected specimens were precisely examined histologically, and the histologic changes were correlated with clinical response and survival. RESULTS: Histologic manifestations of neoadjuvant chemotherapy included coagulation necrosis of cancer cell, appearance of the giant cell with foamy degeneration, extracellular mucin pools, aggregates of foamy histiocytes and/or stromal fibrosis. Histological responses were obtained in 24 (75%) of 32 primary tumors, 13 (81%) of 16 liver metastases, 20 (76%) of 28 lymph node metastases and 3 (18%) of 17 peritoneal disseminations, respectively. Clinical responses were observed in 21 (49%), but there was no statistical survival difference between clinical responders and nonresponders. In contrast, histologic responders survived significantly longer than non-responders. CONCLUSIONS: These results indicate that the grading of the histologic changes is a good prognosticator of patients treated with neoadjuvant chemotherapy, and yields an important information for the selection of postoperative chemotherapy.

Adenocarcinoma↗