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T Kiuchi

Publications and source records attributed to T Kiuchi.

At least 109 records · Page 6Linked to original sources
PubMed1995

On the linguistic representation of medical information: natural language, controlled language, and formal language.

Language is indispensable for the representation of medical information. We classified the methods of linguistic representation into three items: natural language, controlled language, and formal language. The characteristics of these are discussed; we focus especially on the preparation of data and data quality. We present the perspective that linguistic research in medical informatics can be considered as an effort to convert natural language into formal language and vice versa. The problems related to the conversion and the role of controlled language in medical linguistics are discussed in detail.

Language↗
PubMed1994

[Evaluation of liver function in carbon tetrachloride-damaged rabbits by dynamic SPECT: comparison of 99mTc-GSA and 99mTc-Sn colloid].

Technetium-99m-DTPA-galactosyl human serum albumin (99mTc-GSA) is a new ligand that binds specifically to asialoglycoprotein receptors in hepatocytes. We performed liver dynamic SPECT using 99mTc-GSA and 99mTc-Sn colloid in nine normal control rabbits and 17 chronically CCI4-damaged rabbits (total 29 examinations), and also performed liver function tests (ICGR15, Alb, etc). Using the obtained dynamic SPECT data, we analyzed the liver kinetics of 99mTc-Sn colloid using a one-compartment model (hepatic blood flow [K]) and 99mTc-GSA using a two-compartment model (hepatic blood flow and receptor binding [K1], catabolism [K2]). As the CCl4-treated period increased, K1 decreased most significantly. K1 showed the most significant statistical correlation with the results of liver function tests, ICGR15 (p < 0.0001), Alb, PT, HP, Bil and GPT. Further, only K1 showed a correlation with the hepatic fibrosis of the HAI score. From the present results, liver dynamic SPECT using 99mTc-GSA may be said to provide a novel method for the evaluation of hepatic functional reserve.

Animals↗
PubMed1994

Response of the sleep-wake rhythm to an 8-hour advance of the light-dark cycle in the rat.

We have studied the effects of an 8-h advance of the environmental light-dark (LD) cycle on the sleep-wake rhythm in the rat. Electroencephalograms and electromyograms were recorded simultaneously on chart paper through a two-channel telemetry system for 3 days before phase shift (baseline) and 8 days during and after phase shift. Phase advance of the LD cycle led to an increase in both non-rapid eye movement (NREM) and REM sleep. The amount of NREM sleep in the light period correlated positively with that in the preceding dark period for 4 days after phase advance. The duration of REM sleep in the light period correlated negatively with that in the preceding dark period. The results suggest that homeostatic control of the amount of NREM sleep between the preceding dark period and the following light period is disturbed by phase advance of the LD cycle.

Activity Cycles↗
PubMed1994

Spontaneous proliferation of peripheral blood lymphocytes as an indicator of intragraft immune activation in liver transplant patients.

The presence of activated lymphocytes in the blood of transplant recipients is considered to be a marker of an ongoing immune process. In this study, the clinical utility of spontaneous proliferation (SP) of peripheral blood mononuclear cells (PBMC) as a marker of in vivo activation was evaluated by in vitro [3H]thymidine incorporation in 22 patients in the 1st month after liver transplantation. Also immune activation in the graft was monitored by transplant aspiration cytology (TAC-A). In the study period, there were only 2 mild episodes of clinical acute rejection, where SP of PBMC was 1290 and 1541 cpm (vs. 99 cpm averaged in healthy controls). Though SP of PBMC was also increased in systemic infections, a significant positive correlation was observed between SP of PBMC and TAC-A score. In all episodes where TAC-A score was elevated to above 2, SP of PBMC was simultaneously increased to more than 1000 cpm. In 8 patients prophylactically treated with the anti-interleukin-2-receptor antibody, BT563, SP of PBMC was significantly lower compared to 7 patients treated with antithymocyte globulin. It is suggested that SP can be a reliable parameter of the in vivo activation of lymphocytes, which accompanies immune activation in liver graft, and is potentially useful as a sensitive, although rather non-specific, and non-invasive monitoring of intragraft alloresponse.

Adult↗
PubMed1993

Increased arterial ketone body ratio as a prerequisite for recovery after hepatectomy.

It is reported that a prompt increase in the arterial ketone body ratio (acetoacetate/beta-hydroxybutyrate), which reflects the mitochondrial redox state of the liver graft, is a decisive prerequisite for graft survival in clinical liver transplantation. To contrast the rôle of hepatic mitochondrial redox state in partial hepatectomy with that in hepatic replacement, the changes in the ketone body ratio were investigated in 107 cases of hepatectomy. The ketone body ratio in uneventful cases (n = 70) in the first three days after hepatectomy was significantly higher than that in eventful cases. In the uneventful cases, the ketone body ratios were all increased to above 1.0 within two days after hepatectomy, except in diabetics, whose preoperative values did not reach 1.0 under oral glucose load. However, 20 (22.7%) out of 88 cases whose ketone body ratios promptly increased after hepatectomy had mild to moderate complications thereafter. It is suggested that the recovery of hepatic mitochondrial redox state is also a prerequisite in partial hepatectomy, where a reduced and often damaged liver confronts systemic metabolic load.

Adenoma, Bile Duct↗
PubMed1992

Effects of an eight-hour advance of the light-dark cycle on sleep-wake rhythm in the rat.

We observed effects of an 8-h advance of the light-dark (LD) cycle on the sleep-wake rhythm in the rat. On the day phase-advanced, rapid eye movement (REM) sleep increased with its enhanced diurnal amplitude. Non-REM (NREM) sleep gradually increased in parallel with the decrease of its diurnal amplitude. Although the acrophase of NREM sleep gradually advanced after the phase advance, that of REM sleep did not significantly change. We confirmed that diurnal rhythm of REM sleep was hardly shifted and dissociated from the rhythm of NREM sleep under the eight-hour advance of the LD cycle in the rat.

Animals↗
PubMed1992

Receiver operating characteristic (ROC) analysis of the ability of arterial ketone body ratio to predict graft outcome after liver transplantation--its sensitivity and specificity.

To evaluate the ability of arterial ketone body ratio (AKBR; acetoacetate/3-hydroxybutyrate) to predict graft prognosis after liver transplantation, the diagnostic value as a predictive index was compared between AKBR and conventional liver function tests using receiver operating characteristic (ROC) analysis. The ROC curves were determined for AKBR, GOT, GPT, total bilirubin, serum lactate level, and prothrombin time, all of which were measured on the 1st and 2nd postoperative days in 88 cases of liver transplantation. Comparisons of the areas under the ROC curves between AKBR and other tests revealed the significant superiority of AKBR to other tests in predicting graft death within 1 month after transplantation. The present study suggests that AKBR can be used as an accurate index to predict graft prognosis after liver transplantation.

Adolescent↗
PubMed1992

A mixture of nucleosides and a nucleotide alters hepatic energy metabolism 24 hours after hepatectomy in rabbits.

The effect of administering a nucleoside-nucleotide mixture on hepatic energy metabolism was evaluated at 24 h after hepatectomy in rabbits that had had 70% of their livers removed. After hepatectomy, animals were administered continuous intravenous infusion of 2 mL/(kg body wt-h) of 9 g/L NaCl (Group S), 5.99 mmol/L nucleoside-nucleotide mixture (Group N1) or 11.98 mmol/L nucleoside-nucleotide mixture (Group N2). At 24 h after hepatectomy, the hepatic adenylate energy charge in Group S (0.83 +/- 0.01, mean +/- SEM) was significantly lower than that before hepatectomy (0.90 +/- 0.01). By contrast, the values in Groups N1 and N2 after hepatectomy (0.74 +/- 0.04 and 0.73 +/- 0.04, respectively) were significantly lower than that in Group S. The hepatic mitochondrial phosphorylation rate before hepatectomy was 46.40 +/- 4.88 nmol ATP/(mg mitochondrial protein-min). After hepatectomy, significantly greater values were observed in Groups N1 and N2 (69.53 +/- 7.20 and 63.31 +/- 6.11, respectively), yet those values were less than observed in Group S (109.14 +/- 4.80). These results suggest that the nucleoside-nucleotide mixture suppressed the enhancement of hepatic mitochondrial phosphorylative activity at a time when hepatic adenylate energy charge is compromised. Such enhancement is needed to compensate for the increased energy expenditure due to surgical intervention.

Adenosine Diphosphate↗
PubMed1991

Insulinopenia as a risk factor in hepatectomy and its resolution by intraportal insulin administration.

Insulopenia is a possible risk factor in hepatectomy, especially since insulin has been recognized to have a significant hepatotrophic effect. In the current study, insulinopenic patients were defined as those who showed abnormally low insulinogenic indexes (less than 0.6) on the oral glucose tolerance test, compared with those in 22 normal volunteers (1.16 +/- 0.57, mean +/- SD). The insulinogenic index represents the ratio of the cumulative enhancement of immunoreactive insulin (IRI) to the glucose level (delta IRI/delta glucose). Surgical outcomes were studied retrospectively in 17 insulinopenic patients who underwent hepatic resections from January 1987 to July 1988. Six of 10 patients in the major hepatic resection group showed postoperative complications, 5 of whom experienced hepatic failure resulting in hospital death. By contrast, all seven patients in the minor resection group tolerated the operations. From August 1988, intraportal insulin was prospectively administered as a posthepatectomy management technique to nine patients, eight of whom were diagnosed as insulinopenic. These patients all tolerated major hepatic resections including four hepatic vascular exclusion procedures with veno-venous bypass. In conclusion, the current study indicates that insulinopenic patients are high-risk candidates for major hepatic resection and that intraportal insulin administration has a beneficial effect on the postoperative management of these patients.

3-Hydroxybutyric Acid↗
PubMed1991

Effect of glucagon on hepatic energy charge and arterial ketone body ratio in normal rabbits.

Glucagon has been regarded as a hepatotrophic factor, although it is also known to stimulate energy-consuming reactions in the liver, such as gluconeogenesis and ureogenesis. To clarify the effect of glucagon on the hepatic energy metabolism, the changes in arterial ketone body ratio, which reflects the hepatic mitochondrial redox state [( NAD+]/[NADH]), as well as those in energy charge and mitochondrial oxidative phosphorylation of the liver after IV glucagon injection were studied in normal rabbits. Arterial ketone body ratio decreased significantly from 1.04 +/- 0.08 to 0.61 +/- 0.11 (mean +/- SEM; P less than 0.01) within 30 minutes after glucagon injection. Hepatic energy charge also decreased from 0.883 +/- 0.014 to 0.789 +/- 0.014 (P less than 0.01) at 30 minutes, whereas mitochondrial phosphorylation rate inversely increased from 38.4 +/- 9.5 to 87.3 +/- 9.7 (nanomoles adenosine triphosphate per milligram mitochondrial protein per minute; P less than 0.01) at 30 minutes. Arterial ketone body ratio and energy charge were subsequently restored to the initial values at 60 minutes and 2 hours, respectively. The present study suggests that glucagon causes an increase in energy expenditure in the liver that results in a transient decrease in hepatic energy charge accompanied by a decrease in arterial ketone body ratio.

Adenine Nucleotides↗
PubMed1991

Gastric microcirculation and its regulating factors in stress.

Gastric mucosal blood flow and its regulating factors were studied in normal and stressed rats. In addition, vascular regulating factors and the role of CoQ10 anion radical and SOD (superoxide dismutase) level in gastric mucosa were also investigated as well as the influence of 5-HT (5-hydroxytryptamine) on gastric mucosal blood flow. Gastric mucosal blood flow was measured by the hydrogen gas clearance method. The vascular pattern of the stomach was investigated by the infusion method with two-colored silicon rubber. CoQ10 anion radical and SOD levels in gastric tissue were assayed by electron spin resonance (ESR) and radioimmunoassay. The gastric mucosal blood flow decreased significantly early after the induction of stress. Impairment of gastric mucosal blood flow was highly correlated with 5-HT and CoQ10 anion radical and SOD levels. Reduction in gastric mucosal blood flow was consequently due to opening of arteriovenular shunt and hyperpermeability of true capillaries influenced by 5-HT. These results demonstrate that ischemia and reperfusion after reduction of the gastric mucosal blood flow resulted in the sequence of events that led to formation of acute gastric mucosal lesions.

Animals↗
PubMed1991

Quantitative evaluation of English-Japanese machine translation of medical literature.

Although many machine-translation programs are currently available, few evaluation methods of such translation exist for any given application area. It is difficult to evaluate machine-translation systems objectively because the quality of a translation depends on the combination of three factors: the translation program, the dictionary, and the original document. In this study, we developed a quantitative evaluation method for assessing machine translation, which evaluates these three factors separately. We applied this method to the translation of English to Japanese for medical literature and the method proved to be a good indicator for further system improvement. Using this method we also discovered other important points for machine translation, such as the examination of target documents for the construction of a better application dictionary.

Computers↗
PubMed1991

Hepatomuscular failure in septic catabolism: altered muscular response to plasma proteolytic factor in decreased hepatic mitochondrial redox potential.

To estimate the contribution of muscle protein in whole-body protein catabolism, the muscular contribution index (MCI; urine 3-methylhistidine/urine total nitrogen) was determined in 49 cases of elective laparotomy, together with the arterial blood ketone body ratio (KBR; acetoacetate/beta-hydroxybutyrate), which reflects hepatic mitochondrial redox potential. MCI increased after operation and the occurrence of severe infection, provided KBR was maintained above 0.7. In patients with sepsis, however, MCI decreased dependently with KBR (n = 33; p less than 0.01). In these patients, plasma proteolysis-inducing activity determined by in vitro bioassay increased in inverse proportion to KBR (n = 20, p less than 0.01). Moreover, plasma concentrations of not only aromatic but also branched-chain amino acids markedly increased when KBR decreased to below 0.4 (n = 23; p less than 0.05). Thus the role of muscle protein in septic catabolism is diminished under reduced hepatic mitochondrial redox potential, despite the rapid increase of proteolysis-inducing activity. This finally leads to the failure of amino acid uptake by muscles, as well as liver. These results suggest that the deteriorated substrate exchange may form the metabolic background for multiple systems organ failure, which is often preceded by reduced KBR.

Biomarkers↗
PubMed1990

Changes in arterial ketone body ratio in the phase immediately after hepatectomy. Prognostic implications.

Postoperative fluctuations of the ketone body ratio in arterial blood (acetoacetate/3-hydroxybutyrate), reflecting hepatic mitochondrial redox potential, were analyzed in 266 hepatectomized patients in relation to their prognosis. Changes in ketone body ratio were classified into the following two types: a primary decrease at the end of operation and a secondary decrease after transient recovery. Patients were classified into three groups by the primary decrease of ketone body ratio: group 1 (183 cases) with ketone body ratio above 0.7, group 2 (49 cases) between 0.7 and 0.4, and group 3 (34 cases) below 0.4 Ketone body ratio was restored to above 0.7 in 2.5 +/- 0.2 days (mean +/- SE) in all group 2 patients. However, though it was restored within 4.5 +/- 0.4 days in 26 group 3 patients, the other 8 died of multiple organ system failure in 7.4 +/- 2.8 days without recovery of ketone body ratio. This was followed by a secondary decrease in ketone body ratio to below 0.7 in 94 patients, concomitant with complications. The degree of the secondary decrease was positively correlated with that of the primary decrease. In the secondary decrease, of 42 patients with ketone body ratio below 0.4, 28 died of multiple organ failure. Total mortality was 7% in group 1, 12% in group 2, and 50% in group 3. It is suggested that the primary decrease in ketone body ratio at the end of operation is a decisive factor in the prognosis for hepatectomized patients.

Adult↗
PubMed1990

Influence of colloidal carbon phagocytosis as a metabolic load on the hepatic energy metabolism in rats.

The influence of phagocytosis on hepatic energy metabolism was investigated in rats injected with colloidal carbon. Following injection of 6 mg colloidal carbon per 100 g body wt (BW) the hepatic energy charge potential (ECP) remained unchanged. However, oxidative phosphorylation of the isolated mitochondria (PR) increased significantly to 120 and 124% of the control at 1 and 3 hr, respectively, and returned to the normal range at 6 hr. The pyruvate level rose to 195 and 150% at 3 and 6 hr. The lactate level was elevated to 195 and 143% at 3 and 6 hr. Following injection of 20 mg colloidal carbon per 100 g BW, the ECP decreased from 0.865 to 0.783 at 1 hr, but recovered to the normal range thereafter. The PR increased more markedly to 135% at 1 hr, concomitant with an elevation of the ketone body ratio. At 3 hr it remained elevated at 118%, but returned to the normal level at 6 hr. The pyruvate and lactate levels increased to more than 250% at 1 and 3 hr. At 6 hr, the lactate level returned to the control level, but the pyruvate level showed still higher level than the control. These results indicate that phagocytosis exerts an acute metabolic load on the total liver. It was tentatively proposed that parenchymal and nonparenchymal cells in the liver have interrelation in the energy metabolism, and that an enhancement of hepatocellular mitochondrial phosphorylative activity occurs to assist the accelerated metabolism due to phagocytosis.

Adenine Nucleotides↗
PubMed1990

Alternation of gastric mucosal glycoprotein (lectin-binding pattern) in gastric mucosa in stress. A light and electron microscopic study.

Gastric mucosal cells of the rat glandular stomach were studied by light and electron microscopic procedures by use of lectins in the development of acute gastric mucosal lesions. Effects of the H2-receptor antagonist sofalcone (2'carboxymethoxy-4,4'-bis 3-methyl-2) and truncal vagotomy with pyloroplasty on lectin binding sites and distribution were also investigated. Biotinylated lectins in combination with ABC (avidin-biotinyl peroxidase complex) method were used for light and horseradish peroxidase (HRP)-labeled lectins for electron microscopic studies. Gastric mucosal cells showed the specific binding pattern for each lectin by light microscopy. Especially, binding sites and distribution of peanut agglutinin (PNA) were characteristic after induction of stress, truncal vagotomy, and administration of each drug. Staining and distribution increased in the gastric mucosa upward and downward after that. In electron microscopic studies, PNA strongly stained the membranes of the intracellular secretory canaliculi of a parietal cell. These results suggested that alternation of binding sites and distribution was regulated by change of gastric mucosal blood flow and of acidity in the parietal cells. Therefore, increase of glycoconjugate distribution is supposed to be a possibility of cytoprotective effect for a change of environment in the parietal cells.

Animals↗
PubMed1990

Problems and solutions of pedicle screw plate fixation of lumbar spine.

Fifty-seven patients with low back pain and sciatica of various causes were reviewed with reference to problems associated with pedicle plate fixation of the lumbar spine. Eleven percent of patients had neurologic problems postoperatively and 3.5% (two patients) had severe sensory impairments. All patients had this complication in the early phases of the study. Of 297 screws, 17 broke, ie, 5.7%. These breakages occurred in 12 of 57 patients (21%). In patients with spondylolisthesis, the degree of slip correction averaged 53% postoperatively, which decreased to 35% at the 1-year follow-up. Slip angle was maintained after correction. Pedicle screw plate fixation is an effective form of immobilization of the lumbar spine used in achieving arthrodesis. The surgeon must be fully trained in methodology. It is recommended that screw and plate materials be improved to prevent screw breakage.

Bone Plates↗