PubMed Health⌕ Search

Biomedical subjects

T Itoi

Publications and source records attributed to T Itoi.

At least 37 records · Page 2Linked to original sources
PubMed1996

p53 and Ki-67 immunoreactivity and nuclear morphometry of 'carcinoma-in-adenoma' and adenoma of the gall-bladder.

Twenty intramucosal tumors of 'carcinoma-in-adenoma' and 43 adenomas (39 pyloric gland type, 4 intestinal type) of the gall-bladder were studied to establish more precise histological criteria of carcinoma or adenoma in cases of 'carcinoma in pyloric gland type adenoma', to compare carcinoma in adenoma with pure, that is, without adenomatous components, carcinoma, and to confirm the benign nature of spindle cell foci in the adenomas. Ki-67 and p53 immunostaining and nuclear morphometry were used. Eight pure intramucosal cancers were used as controls. The formalin-fixed, paraffin-embedded sections were stained with p53 and Ki-67 antibodies. Spindle cell foci were observed only in the adenoma area of the pyloric gland type, with a frequency of 23% in 39 adenomas, and of 45% in 20 tumors of carcinoma-in-adenoma. Ki-67 staining was negative in 129 of 130 spindle cell foci examined, regardless of their size, and positive in only one focus (550 microns in size, Ki-67 index 0.2%). All of the spindle cell foci were negative for p53 stain. The Ki-67 positive index was 36.6 +/- 5.6% in the 8 pure carcinomas, and 12.5 +/- 1.9% in the carcinoma area of 16 tumors with carcinoma-in-adenoma, while it was 7.9 +/- 1.7% and in the adenoma areas of 16 tumors with carcinoma-in-adenoma and 4.9 +/- 0.5% in the 32 pure pyloric gland adenomas. The p53-protein overexpression was found in seven of eight pure intramucosal cancers, and in one of 16 cancer components of carcinoma-in-adenoma. However, it was not found in any of 16 adenoma components of carcinoma-in-adenoma, and 35 adenomas. Cells of the cancer tissue of carcinoma-in-adenoma showed a significantly larger nuclear area and a larger nuclear minor axis than those of the pyloric gland type adenomas, as well as other architectural and cytologic abnormalities differing from the features of adenomas. These results suggest that clustered spindle cells do not indicate a malignant transformation of adenoma cells and that carcinomas in carcinoma-in-adenoma are different from pyloric gland type adenomas in terms of morphology and proliferative activity. Moreover, the results of the present study indicate that carcinomas. In carcinoma-in-adenoma are lower in malignancy than pure carcinomas, and that their genetic abnormality may differ from that of pure carcinomas.

Adenocarcinoma↗
PubMed1996

Evidence for the interaction between (-)-epigallocatechin gallate and human plasma proteins fibronectin, fibrinogen, and histidine-rich glycoprotein.

Human plasma proteins were subjected to affinity chromatography with (-)-epigallocatechin gallate (EGCg)-agarose, and the bound proteins were examined by sodium dodecylsulfate-polyacrylamide gel electrophoresis. A molecular weight evaluation of the protein bands suggested the presence of three proteins, fibronectin, fibrinogen, and a 75-kDa protein. When human serum was used, the 75-kDa protein dominated the bound fraction. The determination of the partial amino acid sequence of a peptide derived by endopeptidase digestion of this fraction suggested the 75-kDa protein to be histidine-rich glycoprotein (HRG). The presence of these proteins in the bound fraction was confirmed by the immunoblotting method. Affinity chromatography of the individual proteins indicated that fibrinogen and HRG had direct affinity for EGCg. Dot binding assays demonstrated the interaction of EGCg with these proteins. The method also showed that only gallate-containing catechins were bound by these proteins. These data suggest that when EGCg is absorbed in the body through the digestive system, it may interact with these proteins in blood plasma.

Antineoplastic Agents↗
PubMed1994

Acetyl-CoA carboxylase involvement in the rapid maturation of fatty acid oxidation in the newborn rabbit heart.

Fatty acid oxidation rapidly increases in the rabbit heart following birth. By inhibiting carnitine palmitoyltransferase 1 (CPT1), malonyl-CoA is a potent regulator of fatty acid oxidation in the heart. We therefore addressed the hypothesis that a decrease in acetyl-CoA carboxylase (ACC) activity and/or malonyl-CoA inhibition of CPT1 could account for the increase in the ability of the heart to oxidize fatty acids following birth. ACC activity and expression, malonyl-CoA levels, and mitochondrial CPT1 activity were measured in hearts from 1-day, 7-day, and 6-week-old rabbits. CPT1 activity and sensitivity to malonyl-CoA inhibition did not differ between 1-day, 7-day, or 6-week hearts (the IC50 for malonyl-CoA was 32.0 +/- 1.5, 36.0 +/- 0.3, and 36.3 nM, respectively). Western blot analysis with streptavidin showed that all hearts expressed similar amounts of both a 265-kDa (ACC-265) and 280-kDa isoform (ACC-280) of ACC. A progressive and significant decrease in malonyl-CoA levels was seen in 1-day, 7-day, and 6-week hearts (47 +/- 2, 40 +/- 2, and 26 +/- 2 nmol/g dry weight, respectively), paralleling a decline in ACC activity. We hypothesized that these developmental changes could be due to changes in hormonal regulation of cardiac ACC in the postnatal period. In isolated hearts from 1-day-old rabbits, the fatty acid oxidation rate was 9.01 +/- 1.10 nmol.g dry weight-1.min-1. Glucagon (1 ng/ml) did not alter this rate (11.03 +/- 1.42 nmol.g dry weight-1.min-1), but insulin (100 microunits/ml) resulted in a significant decrease in rate (4.81 +/- 0.82 nmol.g dry weight-1.min-1). ACC activity was markedly elevated in 1-day-old hearts perfused with insulin compared to control hearts or glucagon perfused hearts (0.415 +/- 0.052, 0.095 +/- 0.018, and 0.133 +/- 0.013 nmol of malonyl-CoA produced.g dry weight-1.min-1, respectively). Malonyl-CoA levels were also markedly elevated in 1-day hearts perfused with insulin (123.0 +/- 8.3, 2.0 +/- 0.4, and 1.8 +/- 0.6 nmol/g dry weight in insulin, control, and glucagon hearts, respectively). In 7-day-old rabbit hearts, the basal fatty acid oxidation rate had increased to 24.5 +/- 4.8 nmol.mg-1.min-1. In contrast to the 1-day-old hearts, insulin had no significant effect on fatty acid oxidation, although glucagon resulted in a significant increase in rates (38.9 +/- 12.2 and 80.7 +/- 9.1 nmol.g dry weight-1.min-1, respectively).(ABSTRACT TRUNCATED AT 400 WORDS)

Acetyl Coenzyme A↗
PubMed1993

Increase in T cells bearing the gamma/delta receptor associated with lymphoproliferative disease of granular lymphocytes in an infant with intractable diarrhea.

A two-year-old infant with intractable diarrhea and lymphoproliferative disease of granular lymphocytes attributed to a persistent cytomegalovirus infection showed an increase in cells bearing the gamma/delta T-cell receptor (TCR), which accounted for approximately 20% of total peripheral blood lymphocytes and 40% of CD3+ T cells. Of the gamma/delta TCR+ cells, two-thirds were double negative (CD4-/CD8-) and the other one-third CD8 positive. The majority of gamma/delta+ cells were delta TCS 1 positive. The predominance of delta TCS 1 positive cells was also confirmed on biopsy of lymphoid tissues from the colon. After improvement of watery diarrhea and malnutrition following three-month hyperalimentation, the number of gamma/delta TCR+ cells decreased. The patient subsequently died of pneumonia at the age of 2 years and 11 months. A possible site-specific role for the gamma/delta TCR+ cells, particularly delta TCS 1+ cells, in the human intestine is discussed.

Child, Preschool↗
PubMed1993

Glucose use in neonatal rabbit hearts reperfused after global ischemia.

In this study, we measured both glycolysis and glucose oxidation during reperfusion of previously ischemic hearts obtained from 7-day and 6-wk-old rabbits. Isolated working hearts perfused with 11 mM [3H/14C]glucose, 0.4 mM palmitate, 0.5 mM lactate, and 100 microU/ml insulin were subjected to either 30 or 40 min of global ischemia followed by a 60-min period of reperfusion. Recovery of mechanical function was 58% in 7-day-old hearts subjected to 40 min of ischemia. In 6-wk-old rabbits, a 45% recovery of function was seen after only 30 min of ischemia. Addition of 1 mM dichloroacetate (DCA) to the perfusate at reperfusion increased glucose oxidation rates during reperfusion in both 7-day and 6-wk-old hearts (from 102 +/- 22 to 262 +/- 27 and from 280 +/- 63 to 523 +/- 97 nmol.min-1.g dry wt-1, respectively). Addition of DCA, however, resulted in a significant improvement in recovery of mechanical function only in 6-wk-old hearts (from 45 to 67% of preischemic function). These results demonstrate that fatty acid-perfused neonatal rabbit hearts are more able to tolerate ischemia than the matured rabbit hearts. However, our data suggest that there may be less potential to improve mechanical recovery in neonatal hearts during the actual reperfusion period by stimulating glucose oxidation.

Aging↗
PubMed1993

The contribution of glycolysis, glucose oxidation, lactate oxidation, and fatty acid oxidation to ATP production in isolated biventricular working hearts from 2-week-old rabbits.

Immediately after birth, glycolysis and lactate oxidation are the major source of ATP production in the rabbit heart. Although the ability of heart to oxidize fatty acid increases within days, glucose oxidation rates remain low in the first week after birth. To further examine the changes in energy substrate use in the newborn period, we developed a right and left ventricular isolated working heart model, in which 2-wk-old rabbit hearts were perfused with buffer containing 11 mM glucose, 0.8 mM palmitate, 0.5 mM lactate, and 100 microU/mL insulin. Hearts were perfused at a 7.5 mm Hg left atrial preload, a 4.5 mm Hg superior vena cava preload, a 30 mm Hg aortic afterload, and a 4.5 mm Hg pulmonary artery afterload. Glycolytic rates [measured as 3H2O production from (5-3H)-glucose] were 791 +/- 108 nmol/g dry weight.min-1 (mean +/- SEM). Oxidation rates of glucose, lactate, and palmitate (measured as 14CO2 production from 14C substrates) were 94 +/- 15, 126 +/- 13, and 60 +/- 8 nmol/g dry weight.min-1, respectively. In these hearts, the majority of ATP production derived from exogenous sources was obtained from fatty acid oxidation (52%), whereas 11, 23, and 15% of ATP requirements were derived from glycolysis, glucose oxidation, and lactate oxidation, respectively. These studies demonstrate that by 2 wks of age in rabbits, fatty acids are the major source of energy in the heart. However, although the contribution of glucose oxidation to ATP production has increased compared with 1- or 7-d-old rabbit hearts, glucose oxidation rates are still low compared with adult hearts.

Adenosine Triphosphate↗
PubMed1993

[Myocardial energy metabolism in children: age-dependent myocardial utilization patterns of oxygen and energy substrates].

Myocardial utilization patterns of oxygen, lactate, pyruvate, glucose and free fatty acid (FFA) were evaluated in 65 children aged 7 months to 18 years (mean: 7.9 years) without organic cardiac lesions by coronary sinus catheterization via the femoral vein. Myocardial oxygen uptake was positively correlated with age. Myocardial oxygen uptake per unit left ventricular mass and the oxygen extraction rate were negatively correlated with age. The oxygen saturation of coronary sinus blood was significantly lower in younger children. The myocardial lactate and pyruvate extraction rates increased with age, but there was no correlation between lactate or pyruvate uptake and age. The myocardial FFA extraction rate increased with age and the FFA uptake per unit left ventricular mass was positively correlated with age. There was no significant relationship between myocardial glucose utilization and age. Coronary sinus blood flow per unit left ventricular mass was negatively correlated with age. These results indicate that younger children have significantly higher demands for coronary blood flow per unit ventricular mass, significantly higher utilization of oxygen, and significantly lower utilization of FFA, with the highest energy production rates.

Adolescent↗
PubMed1992

Developmental changes in energy substrate use by the heart.

Marked changes in intermediary metabolism occur during development of the heart. In the fetus, the heart utilises lactate and glucose as its main energy substrates, while in the adult, fatty acids are the main energy substrate. The transition from carbohydrate to fatty acid metabolism is a complex process which involves maturation of mitochondrial processes and dramatic changes in circulating levels of fatty acids and lactate. In addition, developmental changes in the use of energy substrates also involve changes in the regulation of the enzymes involved in both carbohydrate and fatty acid utilisation. This paper reviews these changes in intermediary metabolism which occur during myocardial development. The metabolic differences that exist between immature and adult hearts may explain the observed differences in the ability of immature hearts to withstand hypoxaemia or ischaemia.

Adenosine Triphosphate↗
PubMed1989

Coronary sinus cannulation via the femoral vein.

Cannulation of the coronary sinus has been usually accomplished by advancing a catheter through the brachial vein, subclavian vein, or internal jugular vein by venous cutdown or a sheath method. We here describe a technique for cannulation into the coronary sinus through the femoral vein by using a modified catheter. This catheter was easily inserted into the coronary sinus in all of 40 consecutive patients in whom it was attempted.

Catheterization, Central Venous↗
PubMed1989

[An adolescent case of myelodysplastic syndrome following aplastic anemia].

A male with myelodysplastic syndrome (MDS) following aplastic anemia is reported. The patient had been diagnosed as aplastic anemia at 8 years of age, and treated with blood transfusions, anabolic and glucocorticoid steroid hormones. Over a period of subsequent twelve years, he had remission and deterioration. At the age of 21, the patient developed a sudden progression of severe anemia, when his bone marrow showed hyperplasia with prominent dyshematopoiesis and excess of blasts, compatible with MDS by the definition of FAB classification. He received low dose Ara-C therapy, which was ineffective. Nine months later he developed acute monocytic leukemia (M5b) and died. Chromosomal analysis revealed 46, XY at the onset of aplastic anemia, 46, XY, del (6) (q21 q27) at the MDS and 46, XY, -7, +21, 6q-/47, XY, +Y, -7, +21, 6q- at the acute leukemic stage.

Adult↗