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Biomedical subjects

K Iriyama

Publications and source records attributed to K Iriyama.

107 records · Page 6Linked to original sources
PubMedDate not supplied

Effects of exogenous catecholamines on glucose and fat metabolism and on triglycerides in the rat liver during total parenteral nutrition.

An experiment was undertaken to investigate the effects of a continuous infusion of catecholamines on glucose and fat metabolism as well as on nitrogen balance and the amount of triglycerides in the rat liver. The animals were nourished by total parenteral nutrition for 5 days and divided into six groups (n = 5 in each group) on the basis of nonprotein calories given with or without an infusion of catecholamines: group G received 100% of nonprotein calories with glucose, group F received 50% of nonprotein calories with glucose, and the remaining 50% with lipid emulsion, groups Epi-G and Epi-F received epinephrine (1 microgram/kg body weight/min) in addition to the same total parenteral nutrition solution as group G or F, and groups Nor-G and Nor-F received norepinephrine (1 microgram/kg/min) in a similar manner. Each group was administered the same number of total calories (252 cal/kg/day) and the same amount of nitrogen (1.49 g/kg/day). Nitrogen balance was better in group G than in group F. Under catecholamine infusion, there were no significant differences in nitrogen balance between groups Epi-G, Nor-G, Epi-F, and Nor-F, but this parameter improved significantly in group Nor-F in comparison to group F. Liver triglycerides was higher in groups Epi-G and Nor-G than in groups Epi-F and Nor-F. Liver triglycerides was directly related to the blood sugar level. These results indicate that nitrogen conservation is improved with lipid emulsion and that glucose rather than lipid plays a significant role in the genesis of fatty liver, when they are administered under catecholamine-induced stress.

Animals↗
PubMedDate not supplied

Clearance rate of intravenously administered lipid emulsion in canine endotoxemia.

The effect of endotoxemia on the initial catabolism of intravenously given lipid emulsion was investigated in dogs. Two types of endotoxemia were prepared. One was produced by peritonitis which was established by ligation of the artery and vein of an isolated intestine (group 1, n = 6). The other was made by an intravenous injection of Escherichia coli lipopolysaccharide in a dose of 1.5 mg/kg of body weight (group 2, n = 6). Group 1 showed evident peritonitis with a positive limulus test 48 hr after the procedure, but no significant changes of blood sugar level and lactate/pyruvate ratio, while group 2 demonstrated profound hypoglycemia, significant elevation of lactate/pyruvate ratio, and low arterial pressure 3 to 5 hr after the injection of lipopolysaccharide. The clearance rate of intravenously administered lipid emulsion (K value) of group 1 before the peritonitis was 0.0105 +/- 0.0017 and after the peritonitis it was 0.0105 +/- 0.0019. The difference was not significant, while the K value of group 2 which was 0.0133 +/- 0.0056 before the injection of lipopolysaccharide decreased significantly to 0.0069 +/- 0.0024 after the injection of lipopolysaccharide. These results suggest that, in case of endotoxemia with normally maintained oxidation-reduction potential, the initial catabolism of intravenously given lipid emulsion is kept in a normal level, while oxidation-reduction potential is impaired, it is inhibited.

Animals↗
PubMedDate not supplied

Effects of total parenteral nutrition on the development of intestinal endotoxemia in rats: a comparison between glucose and lipid.

The effects of parenteral nutrition (PN) and of the difference in the PN regimens between glucose and lipid emulsion on the development of endogenous endotoxemia were studied in 40 Wister rats. Endotoxemia was induced by occluding the superior mesenteric vein (SMV) for 30 min. The plasma endotoxin in the portal blood at the time of the release of the SMV occlusion and that in the arterial blood 10 min after the release were quantified. Twenty of the 40 rats had received PN for 48 hr prior to the SMV occlusion. Ten of these 20 rats received the total nonprotein calorie (TNPC) solely with glucose, and the other 10 rats received 25% of the TNPC with lipid emulsion. Ten rats had been allowed free access to lab food until the SMV occlusion. The remaining 10 rats underwent neither the SMV occlusion nor PN, and served as the control group. Both the portal and the arterial endotoxin increased after the release of the SMV occlusion, however the portal endotoxin was higher than that of the arterial one. Both the portal and the arterial endotoxin of the rats supported by PN were significantly lower than those of the rats nourished by lab food, while they were higher than the control values. The difference in the PN regimens did not cause any alteration in the endotoxin levels. These results indicate that the development of intestinal endotoxemia was not influenced by the difference in the PN regimens, but it was rather influenced by a presence of intestinal content.

Animals↗
PubMedDate not supplied

Influences of an infusion of lipid emulsion on phagocytotic activity of cultured Kupffer's cells in septic rats.

An experimental study was undertaken to study the influences of an infusion of lipid emulsion on phagocytosis of Kupffer's cells in septic rats. Sepsis was induced in 13 rats by ligating the cecum. Five of them received glucose as the sole nonprotein calorie (septic-glucose group), four of the rats received 25% of the nonprotein calorie with lipid emulsion, Intralipid (septic-lipid group), and the remaining four rats did not receive any intravenous solution and were allowed access to water (septic-fasted group). Another four rats which received neither intravenous solution nor ligation of the cecum served as the control group. The intravenous infusion was carried out for 72 hr. The phagocytotic activity of Kupffer's cells was determined by the ability to engulf latex particles with a size of 1.09 micron, in vitro. The phagocytotic activity was enhanced by the presence of sepsis but it was inhibited by starvation. The difference in the phagocytotic activity between the septic-glucose group and the septic-lipid group was not significant. These results suggest that, insofar as an in vitro study is concerned, a 72-hr infusion of lipid emulsion at a rate of 25% of the total nonprotein calorie does not influence the phagocytotic activity of cultured Kupffer's cell obtained from septic rats.

Animals↗
PubMedDate not supplied

Apolipoprotein C-II modifications associated with an infusion of artificial lipid particles.

Artificial lipid particles used as parenteral nutrition solution do not contain any apolipoproteins when they are infused into the circulation. Despite the absence of apolipoproteins, the metabolism of artificial lipid particles is similar to that of chylomicrons which contain various kinds of apolipoprotein. Of the known apolipoproteins, apolipoprotein C-II (apo C-II) is important in the hydrolysis of triglyceride-rich lipoproteins via involvement in the activation of lipoprotein lipase. Modifications of apo C-II associated with intravenous infusion of a lipid emulsion were investigated in eight patients. Changes in apo C-IIs in high density lipoproteins (HDL), low density lipoproteins (LDL) and very low density lipoproteins (VLDL) together with the plasma level of triglycerides, were quantified before and for 90 min after a bolus injection of a 10% lipid emulsion (1 ml/kg of body weight). Immediately prior to the injection, 54% of the total amount of apo C-II was present in HDL, while 27% was present in VLDL. After 5 to 10 min, the amount of apo C-II in HDL decreased to 29% of the total, while that in VLDL increased to 62%. Subsequently, the amounts of apo C-II in HDL and VLDL began to return to the preinjection levels. These variations in apo C-II were closely correlated with the plasma clearance of triglyceride. The result indicates that the injected lipids are not inert particles during their short intravascular life, but that they acquire apo C-II from HDL.

Adult↗
PubMedDate not supplied

Transfer of apolipoproteins between plasma lipoproteins and exogenous lipid particles after repeated bolus injections or during a continuous infusion of fat emulsion.

Recent studies on the metabolism of artificial lipid particles in a fat emulsion (exo TG) revealed that exo TG acquired apolipoproteins in vivo and in vitro. In particular, apolipoproteins C-II and C-III (apo C-II and apo C-III) are rapidly transferred from high-density lipoprotein (HDL) to exo TG, and return to HDL after the hydrolysis of exo TG. The present study was undertaken to examine whether the movement of apo C-II and apo C-III between HDL and exo TG is influenced by a prior injection of fat emulsion. Two experiments were undertaken. In experiment 1, six male volunteers received three bolus injections of a fat emulsion at a dose of 0.1 g of TG/kg with intervals of 90 min between injections. In experiment 2, the plasma concentrations of triglycerides were maintained at approximately 500 mg/dl for 160 min by the continuous infusion of exo TG. Levels of apo C-II and apo C-III, and the elimination rate of exo TG were followed in each test. In experiment 1, the movement of apolipoproteins between exo TG and HDL was unchanged between the first, second, and third bolus. The elimination rate of exo TG after the third bolus was higher than that after the first bolus. In experiment 2, after the administration of exo TG, the levels of C apolipoproteins in the fraction of HDL began to decrease, and those in the fraction of very-low-density lipoprotein that contained exo TG began to increase. When the concentrations of triglycerides in plasma reached a plateau, the distribution of C apolipoproteins in the lipoprotein fraction also stabilized.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Influence of glucose infusion on levels of phosphomonoesters and adenosine triphosphate as detected by magnetic resonance spectroscopy in a new model of core-cooling of the rat liver in situ.

This preliminary study was undertaken to ascertain whether our newly developed model of the cold ischemic rat liver in situ is applicable to studies designed to assess the metabolism of nutrients. Ischemia of the whole liver of 12 Wistar rats was induced by clamping all supply and drainage vessels. The ischemic liver was perfused in situ. The duration of ischemia of the liver was 20 minutes. Saline was infused into six rats throughout the experiment (group A). An intravenous infusion of glucose at a rate of 0.75 g/h per rat was begun immediately after the induction of blood-reflow to the liver (group B, n = 6). Six rats (group C) did not undergo the procedure for induction of hepatic ischemia and received glucose at the same rate as rats in group B. Changes in hepatic levels of sugar phosphates (phosphomonoesters [PMEs]), inorganic phosphorus, and beta-positioned phosphorus in adenosine triphosphate (beta-ATP) were monitored by 31P magnetic resonance spectroscopy. Ischemia caused a significant increase in levels of PMEs and a decrease in levels of beta-ATP. The infusion of glucose caused a further increase in levels of PMEs and a further decrease in levels of beta-ATP in group B. In contrast, in group C such infusion did not induce any changes in levels of PMEs or beta-ATP. In group A, PMEs and beta-ATP returned to basal levels 5 hours after the induction of blood-reflow to the liver. The changes in levels of PMEs were similar to those in levels of inorganic phosphorus in all groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗
PubMedDate not supplied

Direct measurement of Raman spectra of intact lens in a whole eyeball.

The Raman spectrum of an intact rabbit and rat lens was measured intraocularly without taking it out of a whole eyeball. The Raman spectrum was identical to that of an excised lens. There was no evidence for Raman bands from cornea, aqueous humor, or other ocular tissue in the spectrum of intact lens in the eyeball. The result is an important step toward the clinical application of Raman spectroscopy in the field of cataract research.

Animals↗
PubMedDate not supplied

An application of laser Raman spectroscopy to the study of a hereditary cataractous lens; on the Raman band for a diagnostic marker of cataractous signatures.

Raman spectra were measured for cac-strain mouse (Nakano mouse) lenses in the various stages of cataract formation. The spectra were compared with those of normal mouse lenses of the corresponding ages. A significant difference was observed in the intensity of the Raman band due to an OH stretching mode of lens water (3390 cm-1) between the spectra of cataractous lenses and those of normal lenses. The difference was already obvious in the very incipient stage of hereditary cataract and became more pronounced with cataract development. These observations clearly show that changes in lens water occur during cataractogenesis. We propose in this communication that the intensity change of the Raman band at 3390 cm-1 may be very useful for the diagnostic marker of cataractous signatures.

Animals↗
PubMedDate not supplied

The incidence of early gastric cancer continues to increase in our surgical unit.

We have investigated whether the incidence of early gastric cancer continues to increase. During the last 16 years, from January 1, 1974, through December 31, 1989, 842 patients with primary carcinoma of the stomach were admitted. Of these 842, 676 (80%) underwent gastric resections. During the first 8 years of this study, 391 patients were admitted, and during the second 8 years, 451 patients were admitted. Early cancer in the first 8 years accounted for 28% of the resected cases and 22% of the total cases of gastric cancer. In the second 8 years, early gastric cancer accounted for 38% of the resected cases and 32% of the total number of cases of gastric cancer. The number of early gastric cancers as a proportion of resected cases increased significantly in the second 8 years. Approximately 50% of early gastric cancers were detected as a result of routine upper gastrointestinal examinations which were performed on patients with no clinical features suggestive of a malignant underlying process. We emphasize that gastroenterologists are unlikely to witness a significant increase in the rate of detection of gastric cancer in the early stage as long as both double-contrast radiographic techniques and endoscopic biopsies are performed predominantly only on patients with symptoms that are apparently suggestive of gastric malignancies.

Humans↗
PubMedDate not supplied

Capacity of high-density lipoprotein for donating apolipoproteins to fat particles in hypertriglyceridemia induced by fat infusion.

Acquisition of apolipoproteins C-II (apoCII) and C-III (apoCIII) is essential for the regulation of intravascular metabolism of fat particles (exoTG). This study was undertaken to investigate whether the capacity of high-density lipoprotein (HDL) for donating apoCII and apoCIII is influenced by the concentration of triglycerides (TGs) in plasma. A fat emulsion was infused into six male volunteers at a rate of 0.5 g TG.kg-1.h-1 (priming dose) for 30 min. For the following 160 min, fat was infused a fat emulsion was infused into the same subjects at a rate of 0.3 g.kg-1.h-1 for 160 min after the administration of the priming dose of fat emulsion for 30 min (experiment 2). The plasma TG concentrations and the amounts of apoCII and apoCIII in exo TG and HDL were monitored. The concentration of TG in the plasma stabilized at approximately 500 mg/dl in experiment 1, whereas it continued to increase to 815 +/- 42 mg/dl at 160 min after the start of the infusion of the fat emulsion in experiment 2. In experiment 1, the amount of both apoCII and apoCIII began to increase in exoTG and to decrease in HDL after the initiation of fat infusion. These changes in the distribution of apoC stabilized while the TG concentration remained at a plateau value. However, in experiment 2, the amount of apoC in exoTG did not increase further in response to the additional rise in plasma TG level. These results suggest that there is a relative lack of apoC that can be donated by HDL, depending on the quantitative balance between exoTG and HDL.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

In vitro transfer of apolipoproteins from plasma lipoproteins to artificial lipid particles.

Our earlier studies in vivo revealed that artificial lipid particles (exo TG) in lipid emulsion acquire apolipoprotein C-II (apo C-II) from high density lipoprotein (HDL). Since the transfer of apo C-II to exo TG terminated within a short time after the intravenous injection of exo TG, it is likely that exo TG has a high affinity for apolipoprotein. This hypothesis has been investigated in vitro. Human plasma was incubated at 37 degrees C with or without a 10% emulsion of soybean oil for 5 min and 60 min. After the incubation, the plasma was separated into HDL, low density lipoprotein (LDL) and very low density lipoprotein (VLDL). Levels of apo C-II, C-III and E in each lipoprotein fraction were quantified. When the plasma was incubated without exo TG, the distribution of apo C-II and C-III in the lipoprotein fractions was unchanged after incubations for 5 and 60 min. However, when the plasma was incubated with exo TG, apo C-II and C-III in the HDL fraction decreased after a 5 min incubation, while those in the VLDL fraction increased. Apo E in each lipoprotein fraction did not change after 5- and 60-min incubations regardless of the presence or absence of exo TG.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Inhibitory effects of exogenous insulin on oxidative utilization of glucose in septic rats.

The influence of exogenous insulin on oxidation of U-14C-glucose was investigated by monitoring the production of 14CO2 in septic rats. Ten Wistar rats underwent ligation of the distal third of the caecum and the ligated caecum was punctured with a 21-G needle (septic rats: group S). A group of ten rats was not subjected to these procedures (control rats: group C). Both groups received parenteral nutrition (PN) for the subsequent 27 hours. Non-protein nutrients were provided exclusively as glucose. Five rats in each group received insulin at a rate of 0.64 U/kg/hr for the last six hours of PN, and these rats were designated groups CI and SI. At the 21st hour of PN, 1.563 muCi of U-14C-glucose was injected as a bolus, and the production of 14CO2 was measured. The cumulative production of 14CO2 for the subsequent six hours, given as a percentage of the 14C injected, was 78.22 +/- 6.22% in group C, 86.16 +/- 4.23% in group CI, 62.38 +/- 13.00% in group S, and 54.38 +/- 6.89% in group SI. The elevated levels of blood glucose in rats in group S were reduced by the administration of insulin. These results indicate that the reduction of elevated blood glucose levels by exogenous insulin in the septic rats with antecedent hyperinsulinemia does not reflect an increase in the oxidative utilization of glucose but rather inhibition of the oxidation of glucose.

Animals↗
PubMedDate not supplied

Metabolism of non-protein energy-substrates in septic rats receiving parenteral nutrition.

The influences of sepsis on the metabolism of fatty acid and glucose in rats receiving parenteral nutrition were investigated. The caecum, with its blood supply, was ligated in 10 rats to produce peritonitis and sepsis (septic rats). Twelve rats (control rats) did not undergo this procedure. Five septic rats and six control rats received glucose as a sole nonprotein calorie (septic-glucose rats), and the remaining five septic rats (septic-lipid rats) and six control rats received the same parenteral solution for the first 44 hours, but 25% of the nonprotein calorie was replaced by 10% lipid emulsion for the last 24 hours. At the termination of the parenteral nutrition, 14C-linoleic acid or 14C-glucose was injected as a bolus in the tail vein, and their degradations to 14CO2 and incorporations into the endogenous fat were compared among the three groups. It was demonstrated that the sepsis accelerated the oxidation of fatty acid but did not affect that of glucose. Hepatic lipogenesis with both fatty acid and glucose was accelerated by an infusion of glucose under a septic condition, while it was inhibited by an infusion of lipid emulsion.

Adipose Tissue↗
PubMedDate not supplied

Prediction of post-operative survival time by multivariate analysis in patients with advanced cancer of the stomach.

In order to give a sound basis to a surgeon for the decision that a cancer should or should not be removed, an attempt was made to produce a regression equation to estimate postoperative survival. The relation between postoperative survival and the intraoperative gross-finding of the cancer, the age and sex of the patients, operative curability, histological types of the cancer and the need for combined resections of the adjacent organs were analyzed by the method of multivariate analysis (Quantification Method) in 111 patients with advanced cancer of the stomach. A statistically significant regression equation was obtained, by which the survival months were predicted for a prospective patient. This equation appears to be useful for surgeons as one way of deciding on an appropriate method of operation. The difference between the actual and the predicted survival months was less than twelve months in seventy-six percent of the internal samples.

Adult↗
PubMedDate not supplied

Clinical significance of transfer of apolipoproteins between triacylglycerol-rich particles in lipid emulsions and plasma lipoproteins.

Triacylglycerol (TG)-rich particles in parenteral lipid emulsion have been designed to mimic chylomicrons (CMs), which are exogenous dietary TG-rich lipoproteins. Over the past 30 yr, since lipid emulsions were first used for parenteral nutrition, it has been generally accepted that the intravascular metabolism of TG-rich particles in an emulsion is similar to that of CMs. Both the particles in an emulsion and CMs have a TG core that is stabilized by a surface layer of phospholipids. However, there are major differences between the two types of particles regarding their composition of protein moieties. CMs contain and acquire apolipoproteins, which are essential for the regulation of their intravascular metabolism. In contrast, the TG-rich particles in an emulsion do not contain any apolipoprotein. It has been demonstrated that the particles in an emulsion also acquire various kinds of apolipoprotein during their brief intravascular life. Thus, they may be subject to intravascular metabolic processes similar to those of CMs. In this review, we describe the mechanism by which TG-rich particles in an emulsion acquire apolipoproteins from the perspective of parenteral nutrition with lipid emulsions.

Animals↗