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Biomedical subjects

K Iriyama

Publications and source records attributed to K Iriyama.

At least 37 records · Page 2Linked to original sources

Clinical significance of the DNA index in hematogenous dissemination of aneuploid colorectal cancer.

The DNA index (DI), defined as the ratio of the G0/G1 channel number of tumor cells to the G0/G1 channel number of stromal cells, was analyzed in 121 aneuploid colorectal cancers. In patients with aneuploid tumors, a high DI significantly correlated with tumor penetration beyond the proper muscle layer, positive vascular invasion, and the presence of liver metastasis. This observation led us to conclude that a high DI is likely to be associated with hematogenous dissemination in aneuploid colorectal cancer.

Aneuploidy↗

Prognostic significance of the bromodeoxyuridine labeling index in primary colorectal carcinoma.

The bromodeoxyuridine (BrdU) labeling index was determined in 40 primary colorectal carcinomas by DNA flow cytometry using a BrdU-specific monoclonal antibody. The labeling index, or the fraction of cells in the S-phase of the cell cycle, ranged from 12% to 52%, with a mean of 28% (SEM, 2%). The labeling index in 19 patients was over 30%, which was termed a higher labeling index. There was no significant difference in the labeling index based on the clinical stage of the disease. During the 5-year follow-up after the apparently curative resection, 14 patients died of the disease, 1 died of an unrelated cause, 1 is alive with a recurrence of the disease, and 24 are alive without the disease. The higher labeling index was thus associated with a significantly poorer patient survival (P = 0.03 based on the generalized Wilcoxon test). The present study therefore disclosed that the S-phase fraction of tumor cells thus determined had prognostic significance in primary colorectal carcinoma.

Adult↗

Male inflammatory breast cancer.

We report herein the case of a 68-year-old man diagnosed with inflammatory breast cancer. The patient presented following the rapid onset of redness and swelling over the left anterior chest wall. On examination, the left chest wall and left axilla were extensively hard, and the left upper limb was swollen. Ultrasonography and computed tomography (CT) scanning disclosed a mass in the left breast, about 2 cm in diameter with an unclear margin, and swelling of the major and minor pectoral muscles. Needle biopsy of the breast mass confirmed invasive lobular carcinoma. As a radical operation was considered contraindicated, systemic and intraarterial chemotherapy using 5-fluorouracil (5-FU) and Adriamycin (ADR) were performed. Nevertheless, the patient died of carcinomatous pleurisy 6 months after the initial onset of the disease.

Aged↗

Plasma carnitine kinetics during orthotopic liver transplantation.

BACKGROUND: Carnitine is synthesized mainly in the liver and plays an essential role in the transport of fatty acids in liver mitochondria for subsequent oxidation and energy production. METHODS: The plasma concentrations of free carnitine, acylcarnitine, total ketone bodies, lactate, pyruvate, and hepatocyte growth factor (HGF) were measured during liver transplantation. RESULTS: The plasma free carnitine and acylcarnitine concentrations and the lactate to pyruvate ratio in patients with compromised grafts (group A) were significantly higher than those in patients with well-functioning grafts (group B) after reperfusion. The acylcarnitine concentration in group B decreased after incision, but it remained at a high level in group A. Significant correlations were found between the concentrations of HGF and free and acylcarnitine after reperfusion. CONCLUSION: The accelerated flux of carnitine in the graft may be associated with deterioration of energy metabolism in the graft. An increased acylcarnitine concentration may reflect impaired liver regeneration.

Carnitine↗

Glycogen content of the donor liver and its relation to postreperfusion hepatic energy metabolism.

OBJECTIVES: Many studies have suggested that glycogen in donor livers is an important fuel during cold ischemic time and at reperfusion. However, it remains unclear as to whether the depression of glycogen content in the graft results in a critical derangement of energy metabolism after reperfusion. The purpose of this study was to assess the possible implications of the glycogen concentration of donor livers for the hepatic energy metabolism after reperfusion. METHODS: The glycogen content of 28 donor livers and the plasma concentrations of metabolic substrates were measured during liver transplantation. RESULTS: Gluconeogenesis was maintained even in the glycogen-depleted graft at reperfusion. However, glycogen-depleted grafts produced more ketone bodies until 24 h after reperfusion. Free carnitine concentrations in these patients were significantly higher than those in the patients with glycogen-nondepleated grafts until 48 h after reperfusion. CONCLUSIONS: A glycogen-depleted liver graft may restore essential metabolic function by producing energy substrates through enhanced ketogenesis in the postreperfusion period. The enhanced production of carnitine by the graft provides a substrate for the production of ketone bodies and thus may be relevant to the enhanced ketogenesis.

Energy Metabolism↗

Analysis of tenascin mRNA expression in the murine mammary gland from embryogenesis to carcinogenesis: an in situ hybridization study.

The expression of tenascin gene during murine mammary gland development was analyzed by in situ hybridization with non-radioactive cRNA probes. The aim was to identify whether cells that synthesize tenascin are mesenchymal or epithelial. During embryogenesis, tenascin mRNAs were demonstrated in the epithelial cells of the mammary bud on the 14th and 15th day of gestation, and in the mesenchymal cells from the 14th day to the 17th day, at the epithelial-mesenchymal border of the growing bud. However, cells displaying tenascin mRNAs were not found beyond the bifurcation of the mammary sprout at the beginning of the branching morphogenesis. In post-natal development, tenascin mRNAs were demonstrated in mesenchymal cells surrounding end buds in juvenile mice, in mesenchymal cells surrounding the epithelial cells of plaques, in epithelial cells of the lactating mammary gland, in malignant epithelial cells and in the mesenchymal cells surrounding cancer nests. By immunohistochemistry, tenascin immunoreactivity was shown to have the same spatiotemporal distribution as that of tenascin mRNAs, but was observed to be restricted to the stroma, except in the lactating mammary gland where tenascin was demonstrated in the milk by Western blot. The present study thus showed that both epithelial and mesenchymal cells are sources of tenascin at different stages of murine mammary gland development.

Animals↗

Effects of low dose X-ray irradiation on purine metabolism in mouse splenocytes.

This study examines the influence of low dose X-ray irradiation on purine nucleotide metabolites such as adenosine, inosine, hypoxanthine, xanthine and uric acid, and hence generation of ATP-mediated energy in mouse splenocytes. It was found that, unlike high dose irradiation which promotes membrane damage, low dose irradiation enhances the ability to regulate the energy metabolisms as reflected by the increase in Na+, K(+)-ATPase activity and the adequate activation of the above salvage pathway. Namely, the levels of adenosine, inosine and uric acid significantly increased, while the levels of xanthine and hypoxanthine decreased significantly. Moreover, the cysteine level and superoxide dismutase activity significantly increased at a dosage of 20 cGy.

Animals↗

Elimination of fat emulsion particles from plasma during glucose infusion.

To determine the optimal rate of infusion of a fat emulsion (long-chain triglycerides; LCTs) for parenteral nutrition, the rate of elimination of triglycerides from plasma was measured on two occasions in three healthy subjects, once while receiving LCTs alone (study I) and once while receiving a combined infusion of glucose and LCTs (study 2). In study 1 a hypertriglyceridaemic clamp was set up by raising the concentration of triglycerides to 2 mmol l(-1) (60-min priming infusion at 0.2 g LCTs per kg body-weight per h) and maintaining this value for 300 min. In study 2 a constant infusion of glucose at a rate of 0.32 g per kg body-weight per h was given throughout the 420-min test, and the hypertriglyceridaemic clamp was set up after 70 min. The infusion of glucose induced a progressive increase in the mean(s.d.) concentration of insulin from 4.3(0.4) microU ml(-1) to a plateau value of 11.0(0.2) microU ml(-1) which was sustained during the last 310 min of the study. During the steady state of the hypertriglyceridaemic clamp, the concentration of triglycerides (2.16(0.17) versus 2.12(0.20) mmol l(-1), P = 0.26), as well as the mean(s.d.) rates of infusion of LCTs (0.12(0.08) versus 0.12(0.04) per kg body-weight per h, P = 0.38), did not differ between studies 1 and 2. Thus, an infusion of glucose (and the associated physiological increase in the concentration of insulin) at doses commonly used in parenteral nutrition does not influence the rate of elimination of triglycerides from plasma in normal subjects.

Adult↗

Colorectal cancer in a patient younger than 20 years of age: report of a case and a review of the Japanese literature.

This article presents a case of advanced cancer of the transverse colon seen in an 18-year-old woman who underwent a potentially curative resection. The histological type of cancer was well-differentiated adenocarcinoma. After reviewing the clinicopathological features of 110 colorectal cancer cases in patients younger than 20 years of age compiled from the Japanese literature, the high incidence of poorly differentiated carcinoma (51.5% for poorly differentiated adeno-carcinoma, signet-ring cell carcinoma, mucinous carcinoma, and undifferentiated carcinoma) and of more advanced stages (67.1% for clinical stages IIIb and IV) were found to be characteristic for patients with colorectal cancer younger than 20 years of age. The presence of more advanced disease and the high incidence of poorly differentiated carcinoma thus seem to be related to the low postoperative survival rates. The 2-year survival rate was 19.8% and the 5-year survival rate was 8.8% in colorectal cancer patients younger than 20 years of age.

Adenocarcinoma↗

The metabolic distinctiveness of emulsified lipid particles in the bloodstream and its clinical implications.

The advantages of administering intravenous fat emulsions are well known. Primarily, they are important sources of essential fatty acids; they allow the administration of many calories within a small volume; and they are isotonic compared to body fluid. In this review, the metabolic distinctiveness of parenterally infused fat particles in the bloodstream is evaluated under four main headings: (1) the structure and metabolism of fat emulsion particles; (2) the metabolism of phospholipid-rich fat emulsion; (3) the interactions between fat emulsion particles and plasma lipoproteins; and (4) the acquisition of protein moieties (apolipoproteins) by fat emulsion particles and its clinical implications.

Apolipoproteins↗

Elimination rate of fat emulsion particles from plasma in Japanese subjects as determined by a triglyceride clamp technique.

The elimination rate of emulsion triglyceride (TG) from plasma was investigated in Japanese subjects by a plasma TG clamp technique. Two different studies were performed. In Study 1, a lipid emulsion (20% long-chain triglyceride emulsion: LCT) was infused into a healthy research associate to achieve a certain concentration of TG in the plasma. Thereafter, the infusion rate was adjusted to maintain the chosen concentrations of TG in plasma (namely, 4-5 mmol/L, 3-4 mmol/L, and approximately 2 mmol/L) over a period of 160 min by measuring plasma TG concentrations at 10-min intervals. Concentrations of TG in plasma were clamped within 2.13 +/- 0.13 mmol/L by an infusion rate of 0.10 g.kg-1.h-1, within 3.34 +/- 0.20 mmol/L by an infusion rate of 0.14 g.kg-1.h-1, and within 4.46 +/- 0.22 mmol/L by an infusion rate of 0.11 g.kg-1.h-1. The mean rate of infusion of emulsified TG that had maintained the steady concentrations of TG in plasma was limited to the very narrow range of 0.12 +/- 0.02 g of TG.kg-1.h-1 regardless of the chosen concentration of TG in plasma. Concentrations of nonesterified fatty acids (NEFA) also remained at a fixed level of 1.378 +/- 0.103 mEq/L regardless of the chosen concentration of TG in the plasma. Study 2 was undertaken to determine whether plasma TG concentration reached a plateau during a period when emulsion TG was infused into three different subjects at a rate of 0.12 g.kg-1.h-1. The plasma TG concentrations were steady at a level of 2.04 +/- 0.32 mmol/L, and the plasma NEFA concentrations remained at a fixed level of 1.33 +/- 0.13 mEq/L, over a period of 160 min after 50-min priming infusion. These results indicate that the plasma TG elimination rate was limited to the narrow range of 0.12 +/- 0.02 g.kg-1.h-1 when the fat emulsion was infused into Japanese subjects in a steady state. However, the plasma TG elimination rate in Japanese subjects appeared to be lower than that of Europeans. This may be due to a difference in lipoprotein lipase activity caused by different dietary habits, namely, a lower fat intake.

Adult↗

Clinical significance of serum hepatocyte growth factor in orthotopic liver transplantation.

BACKGROUND: Hepatocyte growth factor (HGF) plays a key role in the regulation of liver regeneration after hepatocyte damage. Changes in HGF production reflect the status of the regeneration process. METHODS: Serum concentrations of HGF and energy substrates were measured during and after liver transplantation in 30 recipients. RESULTS: In the patients with compromised grafts (group A) HGF concentrations were persistently high after reperfusion, whereas in the patients with well-functioning grafts (group B), HGF concentrations decreased rapidly and remained low 4 hours after reperfusion. The patients in group A who died had persistently high concentrations of HGF. The surviving patients with reversible primary graft dysfunction in group A exhibited low concentrations 48 hours after reperfusion. The decrease in HGF concentration preceded the decrease in aspartate aminotransferase concentration. The metabolic parameters that reflect carbohydrate metabolism by the graft paralleled the changes in HGF. CONCLUSIONS: HGF may be more sensitive and specific in predicting early graft function than prothrombin time, ratio, aspartate aminotransferase, or arterial ketone body ratio. The determination of HGF levels after liver transplantation may yield valuable information for evaluating early graft function and making an early decision to repeat a graft procedure in an acutely ill patient.

Adolescent↗

Effects of point mutations at the flexible loop glycine-67 of Escherichia coli dihydrofolate reductase on its stability and function.

To elucidate the role of a flexible loop (residues 64-72) in the stability and function of Escherichia coli dihydrofolate reductase, glycine-67 in this loop was substituted by site-directed mutagenesis with seven amino acids (Ala, Cys, Asp, Leu, Ser, Thr, and Val). The circular dichroism spectra suggested that the confirmation of the native structure was affected by the mutations in both the presence and absence of NADPH. The free energy change of unfolding by urea decreased in the order of G67A > G67S > or = wild-type > or = G67D > G67T > G67C > or = G67L > G67V. The steady-state kinetic parameters for the enzyme reaction, Km and kcat, were only slightly influenced, but the rate of the hydride transfer reaction was significantly changed by the mutations, as revealed by the deuterium isotope effect on the enzyme activity. These results suggest that site 67 in the flexible loop, being very far from the active site, plays an important role in the stability and function of this enzyme. The characteristics of the mutations were discussed in terms of the modified flexibility of the native structure, compared with the results of mutations at site 121 in another flexible loop.

Base Sequence↗

Expression of tenascin in gastric carcinoma.

Tenascin expression was determined by an immunohistochemical technique in 120 surgical specimens of gastric carcinoma to investigate its relationship with clinicopathological factors. Tenascin expression was more prominent in the neoplastic area than in the adjacent non-neoplastic mucosa. Tenascin was frequently observed in gastric mucosa with diffuse chronic gastritis, glandular atrophy and intestinal metaplasia. In the neoplastic area, tenascin expression was positive in 72 cases (60 per cent). Tumours with a high frequency of tenascin expression included: Borrmann type II (19 of 20), well or moderately differentiated tumours (52 of 63), tumours with expansive growth and with an intermediate growth pattern (40 of 42), and those with a medullary or intermediate-type stroma (55 of 73). There was no significant relationship between tenascin expression and age, sex, depth of tumour invasion, lymph node metastasis, invasion to lymphatic vessel, venous invasion and the 4-year survival rate.

Biomarkers, Tumor↗

Results of combined resection of invaded organs in patients with potentially curable, advanced gastric cancer.

OBJECTIVE: To assess the role of combined resection of neighbouring organs that have been invaded by cancer in patients with potentially curable, but advanced, gastric cancer. DESIGN: Retrospective follow up study. SETTING: University department of surgery. SUBJECTS: 204 patients (from a consecutive series of 745 who had had gastric resection for cancer) all of whom had undergone potentially curative operations for advanced disease: 91 had had combined resection of other invaded organs. RESULTS: Five year survival was 65% for 113 patients who had gastrectomy alone and 46% for 91 patients who also had other affected organs resected (p < 0.02). CONCLUSION: We recommend resection of all organs that have been invaded by cancer, provided that there is no evidence such as widespread nodal involvement, peritoneal dissemination, or extensive hepatic metastases, that would make cure impossible.

Diaphragm↗

Prognostic significance of histological type in gastric carcinoma with invasion confined to the stomach wall.

Survival was determined after resection for the two main histological types of gastric carcinoma, intestinal (n = 223) and diffuse (n = 170), in 393 patients with pT1 or pT2 tumours. Lymph node metastases were present in 94 patients. The 10-year survival rate was significantly lower for patients with intestinal-type than for those with diffuse-type carcinoma (72 versus 91 per cent, P < 0.005). In patients without nodal involvement, the 10-year survival rate was still lower for those with intestinal-type cancer (70 versus 94 per cent, P < 0.01). Recurrence of carcinoma was more often by haematogenous dissemination in patients with intestinal-type cancer. Although the results of resection for pT1 or pT2 gastric carcinoma can be acceptable, the introduction of adjuvant therapy based on histological findings may be necessary for patients with the intestinal type of cancer to prevent haematogenous spread of carcinoma to the liver.

Adenocarcinoma↗