Biomedical subjects

J Hayakawa

Publications and source records attributed to J Hayakawa.

At least 73 records · Page 4Linked to original sources

PubMed1994

[Effect of celiac plexus block and thoracic epidural block on arterial ketone body ratio].

We evaluated the effect of intraoperative celiac plexus block (CPB) and thoracic epidural block (TEB) on arterial ketone body ratio (AKBR) in the patients undergoing total or partial gastrectomy. Mean arterial pressure (MAP), heart rate, AKBR, and arterial blood gas were measured at the end of esophago-jejunostomy, gastro-duodenostomy, or gastro-jejunostomy (pre-block) and at the end of operation (post-block), respectively. After pre-block measurement, CPB with 99.5% ethanol 15-20 ml was carried out in 8 patients with advanced gastric cancer (CPB group); TEB with 2% lidocaine was performed on 8 patients (TEB group); and neither CPB nor TEB was done on 8 patients (control group). A significant reduction in MAP was observed after CPB and TEB. There was no difference in the degree of MAP decrease between CPB group and TEB group. No change in MAP was observed in control group. In CPB group significant decreases in AKBR, pH, and BE were induced by CPB. However, there were no difference in AKBR, pH, and BE between pre-block values and post-block values in TEB group as in the control group. These findings suggest that ethanol used in CPB reduces the redox state of hepatic mitochondria and increases lactate. Therefore we should pay attention to the changes in AKBR, pH, and BE after celiac plexus block with ethanol.

Aged↗

PubMed1994

[Effect of dopamine and prostaglandin E1 on portal venous oxygenation].

We evaluated the effects of dopamine (DA) and PGE1 on portal venous oxygenation in patients undergoing gastrectomy. Thirty-two patients studied were anesthetized with isoflurane and nitrous oxide in oxygen. They were divided into three groups: DA was infused at a rate of 3 micrograms.kg-1.min-1 in 10 patients (DA group), PGE1 was infused at a rate of 0.02 microgram.kg-1.min-1 in 10 patients (PGE1 group), and the remainders did not receive DA nor PGE1 (control group). There were no significant differences in PaO2 and SaO2 among three groups. However, portal venous PO2 and SaO2 in DA and PGE1 group were significantly higher than those in the control group. These results suggest that DA and PGE1 elevate the portal venous PO2 and SO2 by increasing splanchnic blood flow more than its oxygen uptake or without increasing splanchnic oxygen uptake, and increase the oxygen supply to the liver.

Aged↗

PubMed1994

[Arterial ketone body ratio and its modification by PGE1 in elderly patients during gastrectomy].

We evaluated the change in arterial ketone body ratio (AKBR), which is a parameter to indicate the liver cells, during gastrectomy, and effect of PGE1 on its change in the elderly patients, compared with the younger patients. Twenty patients studied were elderly (above 65 years) and twenty were younger (below 60 years). PGE1 was administered in 10 elderly and 10 younger patients, and the remainders did not receive PGE1. Decrease in AKBR during the resection of stomach and immediate increase in AKBR after the resection of stomach were observed in younger patients. On the other hand, prolonged decrease in AKBR after the resection of stomach was observed in elderly patients. Administration of PGE1 accelerated the restoration of AKBR after the resection of the stomach in elderly patients and caused an increase in AKBR during the resection of stomach in younger patients. These findings suggest that hepatic functional capacity in elderly patients is less than that in younger patients, and that administration of PGE1 has a protective effect on liver in both elderly and younger patients.

Aged↗

PubMed1993

Identification of a novel population of CD8 alpha+ beta- bone marrow-derived dendritic epidermal cells. This unique population is subsequently outnumbered by thymus-independent expansion of the CD8 alpha+ beta+ dendritic epidermal cells.

Maturation of some T cell populations has been suggested to occur in epithelial tissues. The CD8 molecule, which is expressed as heterodimers made of alpha/beta-chains on virtually all peripheral T cells, is preferentially expressed as homodimers made only of alpha-chains on a subset of CD8+ mouse gut intraepithelial lymphocytes, which arise from bone marrow (BM) precursors in a thymus-independent mechanism. This unique population of CD8 alpha+ beta- T cells, however, has not been identified in other lymphoid tissues in normal adult mice. Because our previous study demonstrated that reconstitution of thymectomized irradiated mice with T cell-depleted BM cells resulted in the appearance of CD8+, TCR-alpha beta+ dendritic epidermal cells (DEC) and suggested that a proportion of the BM-derived DEC may mature within the epidermis, we asked whether the unique phenotype of CD8 alpha+ beta- could be detected among the CD8+ BM-derived DEC. In this report for the first time we identified this unique population of CD8 alpha+ beta- cells among the DEC. Although this population comprised the predominant fraction of the BM-derived DEC in the early post-transfer period (2 to 3 mo), gradual shift from the CD8 alpha+ beta+ phenotypes occurred during the late post-transfer period (4 to 6 mo) independently of the presence of the thymus. Kinetic studies on the BM-derived DEC revealed that this phenotypic shift could be caused by the subsequent expansion of the CD8 alpha+ beta+ DEC. In contrast, the CD8 alpha+ beta- population was the major subset of the BM-derived intraepithelial lymphocytes throughout the entire observation period and the phenotypic shift with age was never observed. These results indicate that CD8 alpha+ beta- cells are preferentially detected on T cells that home to the epithelial tissues and that in the epidermis, but not in the gut epithelia, the subsequent expansion of the CD8 alpha+ beta+ DEC would dilute the high number of the CD8 alpha+ beta- cells.

Animals↗

PubMed1993

Cytotoxic T cell responses to minor H-43 alloantigens in H-43a and H-43b mice. Distinctive MHC class I restriction specificity and clonal inactivation are inherent properties of the H-43 system.

Our previous studies demonstrated that CTL responses to the newly identified minor H-43a and H-43b alloantigens induced in H-43b and H-43a responder mice, respectively, utilized the same H-2Kb (Kb) MHC class I restriction element, whereas many allelic class I products were not utilized. Also, a single i.v. injection of H-43b recipient mice with spleen cells (SC) from H-43 congenic mice induced specific and lasting CTL tolerance to H-43a rather than priming. We have produced a H-43b C3H.AU mouse strain (H-2p), which we regard as H-43 congenic to the C3H.NB (H-2p, H-43a) strain. Using this strain we demonstrate that Kp and/or Dp alleles can serve as class 1 restricting elements in the CTL responses to H-43a and H-43b alloantigens. Injection of H-43a recipient mice with antigenic H-43b SC from the paired H-43 congenic abrogated the anti-H-43b CTL response, irrespective of MHC class I specificity, i.e., in the contexts of Kb and of Kp and/or Dp elements. A corresponding result was obtained upon injection of H-43b recipient mice with congenic H-43a SC. The tolerance-inducing capacity of H-43a congenic SC was so strong that injection of these cells into H-43b responders that had previously received immunogenic H-43a SC completely blocked the previously activated Kb-restricted memory CTL activity specific for the H-43a alloantigen.

Animals↗

PubMed1993

Cardiac hypertrophy in juvenile visceral steatosis (jvs) mice with systemic carnitine deficiency.

We have reported the clinical and biochemical findings in juvenile visceral steatosis (jvs) mice with systemic carnitine deficiency. This paper is the first report about cardiomyopathy in jvs mice. Adult jvs mice (at the age of 2-3 months) show cardiac hypertrophy which is caused by enlargement of the cardiac muscle cell associated with increases of non-collagen protein and DNA content. Carnitine administration (2 mg/head, twice a day, from 1 month of age) significantly suppresses the cardiac hypertrophy, showing that carnitine deficiency plays an important role in the development of the cardiac hypertrophy. The discovery of cardiac hypertrophy in carnitine-deficient jvs mice will lead to clarification of the pathophysiology of cardiomyopathy in systemic carnitine deficiency in human beings.

Animals↗

PubMed1993

Bone marrow-derived dendritic epidermal T cells express T cell receptor-alpha beta/CD3 and CD8. Evidence for their extrathymic maturation.

The majority of murine Thy-1+ dendritic epidermal T cells (DETC) express virtually identical TCR encoded by V gamma 5 and V delta 1 genes and are derived from early fetal thymic precursors. However, not consistent with this notion is an early finding that DETC arise continuously from bone marrow (BM) precursors by a thymus-independent mechanism. To address this issue, donor-type DETC were characterized in lethally irradiated mice that were reconstituted by Thy-1-disparate BM cells with or without a thymus. The BM-derived DETC, unlike their normal TCR-gamma delta counterparts, were found to express the TCR-alpha beta/CD3 complex and CD8, and their migration to the epidermis dermis occurred independently of the thymus. The numbers of the BM-derived DETC increased with time and reached a plateau 6 mo after BM transfer, at which time the TCR-alpha beta/CD3 complex was expressed on a small fraction of the DETC in athymic BM chimeras. Although no further increase in the number was observed at later times, at 1 yr after transfer most of the BM-derived DETC came to express the TCR-alpha beta/CD3 complex in the absence of thymic influence. By contrast, most of BM-derived T cells in other lymphoid organs from athymic BM chimeras still failed to express the TCR-alpha beta/CD3 complex even at 1 yr after transfer. These results suggest that extrathymic differentiation of BM-derived DETC could occur with the epidermal microenvironment.

Animals↗

PubMed1993

A rapid molecular diagnosis of posttransfusion graft-versus-host disease by polymerase chain reaction.

A woman with recurrent Paget's disease of the vulva developed acute graft-versus-host disease (GVHD) 12 days after radical surgery and massive blood transfusion. Molecular diagnosis of lymphocyte chimerism in the peripheral blood was made by polymerase chain reaction (PCR) directed against a Y chromosome-specific sex-determining region Y (SRY) gene. PCR with skin biopsy after onset of GVHD also revealed infiltration of SRY-positive donor lymphocytes. The diagnosis was confirmed by HLA-DNA typing with PCR-sequence-specific oligonucleotide that revealed the presence of complex HLA-DR chimerism in the peripheral lymphocytes collected after onset of GVHD. The use of SRY-directed PCR is a rapid technique for the early diagnosis of acute posttransfusion GVHD in female patients.

Base Sequence↗

PubMed1992

Carnitine administration to juvenile visceral steatosis mice corrects the suppressed expression of urea cycle enzymes by normalizing their transcription.

Previous studies in our laboratories have revealed that juvenile visceral steatosis mice show suppressed transcription of urea cycle enzyme genes during development and are systemically deficient in carnitine. It has not yet been explained, however, how this carnitine deficiency relates to the abnormal gene expression. We investigated the effect of carnitine on abnormal gene expression, growth retardation, and fatty liver. Carnitine administration relieved the suppression of the developmental induction of two urea cycle enzymes examined, carbamoyl-phosphate synthetase and argininosuccinate synthase, and kept the activities of enzymes normal. However, carnitine did not reduce accumulated lipid in the liver to the normal level. These results suggest that carnitine deficiency plays an important role in the abnormal expression of urea cycle enzyme genes and that the abnormal expression of the genes is not directly caused by lipid accumulation in the liver.

Aging↗

PubMed1992

Abnormal expression of urea cycle enzyme genes in juvenile visceral steatosis (jvs) mice.

Juvenile visceral steatosis (jvs) mice from the C3H-H-2 degrees strain have markedly low levels of all the hepatic urea cycle enzymes (Imamura et al. (1990) FEBS Lett. 260, 119-121). The steady state levels of messenger RNA for the four urea cycle enzymes examined and also for albumin and serine dehydratase were severely reduced in the liver. The levels of mRNA for other liver-specific enzymes including aldolase B and phospho enol pyruvate carboxykinase did not vary significantly from normal littermates. As for extrahepatic expression of the urea cycle enzymes, only argininosuccinate synthetase in the kidney was decreased. Nuclear run-on experiments showed reduced transcription of the corresponding genes, which mostly accounts for the low mRNA levels. Furthermore, the time-course of mRNA accumulation from 5 days of age showed that the developmental induction of hepatic carbamyl phosphate synthetase and argininosuccinate synthetase mRNAs was strongly suppressed. These results suggest that jvs affects not only the regulation of the tissue-specific expression of the urea cycle enzymes but also the regulation of their developmental induction.

Animals↗

PubMed1992

Structural characterization of bacitracin components by Frit-fast atom bombardment (FAB) liquid chromatography/mass spectrometry (LC/MS).

The structural characterization of minor components of bacitracin (BC) complex was carried out using a technique of liquid chromatography/mass spectrometry (LC/MS). Satisfactory total ion current chromatogram of BC complex and excellent mass spectra of many components were given by Frit-fast atom bombardment (FAB) LC/MS analytical system, and the structures of 13 minor components could be proposed. The 13 minor components were classified into two groups, bacitracin A (BC-A) related components and bacitracin F (BC-F) related components depending on their common N-terminal moieties. The structures of BC-A related components and BC-F related components were the same as those of BC-A and BC-F, respectively, except that one to three of isoleucine and leucine residues are replaced by valines. The BC-F related components were degradation products of BC-A related components through the same degradation process as that of BC-A.

Amino Acid Sequence↗

PubMed1992

[Lobenzarit disodium (CCA)--induced diabetes insipidus in a patient with rheumatoid arthritis].

A 44-year-old female with 16-year history of rheumatoid arthritis visited Akiru Hospital with complaints of a thirst, a dry mouth and a general fatigue. One week prior to admission, the patient manifested excessive thirsty feeling, a body weight loss and a sleepless by the polyuria. She has been given 5-10 mg of prednisolone and 240 mg of lobenzarit disodium (CCA) in a day for 11 months. A hematologic examination showed no abnormality, and the examination of her serum showed the following values: BUN, 9.3 mg/dl; creatinine, 0.9 mg/dl; sodium, 139 mEq/l; chloride, 102 mEq/l; potassium, 3.9 mEq/l; osmolality, 290 mOsm/l. Plasma antidiuretic hormone (ADH) level increased slightly (6.0 pg/ml). Examination of her urine revealed specific gravity, 1.005; no trace of glucose, protein, blood and ketones; normal sediment; and osmolality, 209 mOsm/l. The patient was given exogenous ADH (10 units of vasopressin tannate in oil, intramuscularly) to obtain a diagnosis, and she was found to be unable to concentrate her urine more than 1.008 in the specific gravity. A water restriction, as a test for diabetes insipidus, also failed to concentrate her urine in the specific gravity and in the osmolality. Together with these findings, the patient was diagnosed to be a diabetes insipidus, and CCA was seemed to account for the disease. This unfavorable effect of CCA appeared to be reversible, since the patient recovered her urinary concentrating ability after the medication of CCA was discontinued.

Adult↗

PubMed1992

[Change in arterial ketone body ratio during gastrectomy and mastectomy].

We evaluated the influence of operative procedure on arterial ketone body ratio (AKBR), which indicates the function of the liver cells, in patients undergoing gastrectomy or mastectomy. AKBR during the stomach resection was significantly lower than that during the breast resection. A significant reduction in AKBR due to induced hypotension was observed in mastectomy group. SGOT and SGPT increased significantly in gastrectomy group, but unchanged in mastectomy group on the first and the seventh postoperative days. On the first post-operative day, SGOT and SGPT in gastrectomy group were significantly higher than those in mastectomy group. These findings suggest that influence of operative procedure on the liver during gastrectomy is more serious than that during mastectomy.

Adult↗

PubMed1992

[Effect of hypocapnia on arterial oxygenation during induced hypotension].

We evaluated the effects of hypocapnia on arterial oxygenation during induced hypotension with nitroglycerin (TNG) or prostaglandin E1 (PGE1) in patients undergoing mastectomy. Of the 20 patients studied, 10 belonged to TNG group and 10 belonged to PGE1 group. Mean arterial pressure during induced hypotension was maintained at 70% of the values observed before hypotension. A significant decrease in PaO2 was observed during hypotension under normocapnia (PaCO2 35-40 mmHg) in both groups. In addition, small but significant reduction in PaO2 from 128.5 +/- 23.7 mmHg to 122.5 +/- 25.5 mmHg in TNG group and from 129.9 +/- 11.9 mmHG to 116.7 +/- 15.6 mmHg in PGE1 group were induced by hypocapnia (PaCO2 27-30 mmHg) during hypotension. These findings suggest that usual dose of TNG and PGE1 might not or might partially inhibit hypoxic pulmonary vasoconstriction.

Adult↗

PubMed1992

[Effect of prostaglandin E1 on arterial ketone body ratio during gastrectomy].

We evaluated the effect of prostaglandin E1 (PGE1) on arterial ketone body ratio (AKBR), which is a parameter to indicate the function of the liver cells, in the patients undergoing total or subtotal gastrectomy. Twenty patients were divided into two groups: continuous intravenous administration of PGE1 (0.02 micrograms.kg-1.min-1) was started from 30 minutes after the beginning of the operation in 10 patients, and the remainders did not receive PGE1. AKBR levels at 30 minutes after the beginning of the operation (during the resection of stomach) were significantly lower than those after the resection of stomach in both groups. A significant increase in AKBR caused by the administration of PGE1 was observed during the resection of the stomach in PGE1 group. However, almost no change was observed in AKBR during the resection of the stomach in control group. These findings suggest that the administration of PGE1 has a protective effect on liver which is due mainly to the increase in hepatic blood flow during the resection of stomach.

Adult↗

PubMed1991

Direct interfacing of high-speed countercurrent chromatography to frit electron ionization, chemical ionization, and fast atom bombardment mass spectrometry.

Direct interfacing of analytical high-speed countercurrent chromatography (HSCCC) to mass spectrometry (MS) was demonstrated for the first time, and its performance was evaluated in terms of chromatography and mass spectrometry. HSCCC/MS interface was based upon Frit electron ionization (EI), chemical ionization (CI), and fast atom bombardment (FAB). Separations were conducted by newly developed HSCCC-4000 with a 2.5-cm revolutional radius and 0.3 mm or 0.55 mm i.d. multilayer coiled column which is capable of operating at a maximum speed of 4000 rpm. To demonstrate the potential capability of HSCCC/frit MS, three indole auxin mixtures, two mycinamicin (macrolide antibiotics) mixtures, and a colistin complex (peptide antibiotics) were analyzed under HSCCC/frit EI, CI, and FABMS conditions, respectively. The data obtained indicated that interfacing to frit/MS does not adversely affect the chromatographic resolution and mass spectra provide structural information. The HSCCC system interfaced with a frit-equipped mass spectrometer will offer a new dimension in the separation of biologically important substances.

Chromatography↗

PubMed1991

Improvement of chemical analysis of antibiotics. XVII. Application of an amino cartridge to the determination of residual sulphonamide antibacterials in meat, fish and egg.

A simple, rapid and reliable method for the determination of residual sulphonamide antibacterials (SAs) (sulphathiazole, sulphisozole, sulphamethoxazole, sulphadiazine, sulphamerazine, sulphadimidine, sulphamonomethoxine, sulphadimethoxine, sulphamethoxypyridazine and sulphaquinoxaline) in meat, fish and egg was developed using a combination of high-performance liquid chromatography (HPLC) and clean-up with an amino-type prepacked cartridge. SAs were extracted with ethyl acetate and applied to a Baker 10 amino cartridge. After elution from the cartridge, SAs were determined by HPLC. The recoveries at the level of 0.5 ppm were 73.7-99.1% and the detection limits were 0.05 ppm. The analysis time per sample was about 45 min.

Anti-Bacterial Agents↗

PubMed1991

Animal model of systemic carnitine deficiency: analysis in C3H-H-2 degrees strain of mouse associated with juvenile visceral steatosis.

We analyzed carnitine profiles in C3H-H-2 degrees strain of mouse associated with fatty liver, hyperammonemia and hypoglycemia (Koizumi et al., 1988). Carnitine levels in serum, liver and muscle of mouse with fatty liver were markedly decreased in comparison with those of control mouse (littermates without fatty liver). This is a useful animal model to analyze the role of carnitine in lipid, amino acid and carbohydrate metabolism.

Aging↗