Biomedical subjects

M Nonaka

Publications and source records attributed to M Nonaka.

At least 109 records · Page 6Linked to original sources

PubMed1999

Effect of dietary antioxidants on serum lipid contents and immunoglobulin productivity of lymphocytes in Sprague-Dawley rats.

Sprague-Dawley rats were fed alpha-tocopherol, tocotrienol, or quercetin to examine their dietary effects on serum lipid contents and immunoglobulin productivity. In tocotrienol or quercetin groups, serum triglyceride was lower than in the none group. Moreover, in the alpha-tocopherol group, serum IgA level and IgA productivity of MLN lymphocytes were high, while in the tocotrienol group, IgM productivity of spleen lymphocytes and IgA, IgG, and IgM productivity of MLN lymphocytes were high. Thus, we suggested each antioxidant had different effects in rats.

Animals↗

PubMed1999

Surgical treatment of internal carotid artery anterior wall aneurysm with extravasation during angiography--case report.

A 54-year-old female presented subarachnoid hemorrhage from an aneurysm arising from the anterior (dorsal) wall of the internal carotid artery (ICA). During four-vessel angiography, an extravasated saccular pooling of contrast medium emerged in the suprasellar area unrelated to any arterial branch. The saccular pooling was visualized in the arterial phase and cleared in the venophase during every contrast medium injection. We suspected that the extravasated pooling was surrounded by hard clot but communicated with the artery. Direct surgery was performed but major premature bleeding occurred during the microsurgical procedure. After temporary clipping, an opening of the anterior (dorsal) wall of the ICA was found without apparent aneurysm wall. The vessel wall was sutured with nylon thread. The total occlusion time of the ICA was about 50 minutes. Follow-up angiography demonstrated good patency of the ICA. About 2 years after the operation, the patient was able to walk with a stick and to communicate freely through speech, although left hemiparesis and left homonymous hemianopsia persisted. The outcome suggests our treatment strategy was not optimal, but suture of the ICA wall is one of the therapeutic choices when premature rupture occurs in the operation.

Aneurysm, Ruptured↗

PubMed1999

[Effects of coronary artery bypass surgery on the stunned and hibernating myocardium in the cases with depressed left ventricular function].

Chronic left ventricular (LV) dysfunction may result from irreversible damage (cell death), stunned myocardium (ST), or hibernating myocardium (HB). However, both of ST and HB are expected to be reversible. In this report, the effects of coronary artery bypass grafting on the regions of ST and HB were evaluated in 37 patients with less than 40% of LV ejection fraction. The patients were divided into two groups. Group I consisted of the patients whose postoperative LV ejection fraction rose by more than 10% compared to the preoperative value. Group II included the remaining patients with no significant improvement. After successful revascularization, 61% of HB changed to ST and 52% of ST to normal in group I. These changes were significant in comparison with group II because 48% of HB and 83% of ST in group II remained unchanged. Immediate or rapid recovery of HB hardly occurred in both of the groups. To recover normal function, HB may pass through a stage of ST on reperfusion. On the other hand, it is difficult to determine whether HB and ST with no significant changes after reperfusion are irreversibly damaged or reversible and take time to return to normal.

Aged↗

PubMed1999

[ASO as a risk factor of emergency CABG].

The presence of lower extremity arterial occlusive disease (arteriosus sclerosis obliterance of lower extremity) is an important risk factor for patients undergoing emergency coronary artery bypass operations. Those patients had higher mortality and morbidity rates related to the complications of intraaortic balloon pumps (IABP). If lower extremity ischemia is observed, rapid procedures such as removal of the IABP with or without thrombectomy and femorofemoral crossover interposition of a graft should be performed.

Aged↗

PubMed1999

Five cases of asymptomatic spontaneous pneumothorax.

Asymptomatic spontaneous pneumothorax (ASPT) is an uncommon condition. Between January 1, 1989 and December 31, 1997, 269 patients were admitted to our department with spontaneous pneumothorax. Of the 269 patients, 5 had no symptoms at the time of discovery. Their ages ranged from 15 to 61 years (mean, 37.8 years), and all of them were male. Of the 5 patients with no complaints, 2 had bilateral metachronous pneumothoraces and 3 had hemilateral pneumothorax. All of these ASPTs were revealed by chest roentgenographs taken during medical examinations or follow-up studies relating to other diseases. The mean value of body mass index (BMI) was 19.96 +/- 1.4 (range 18.7 - 22.1). Two of the 5 patients underwent bilateral partial lung resection. Histopathological examination of the resected specimens showed elastofibrosis, scar formation, and an interruption of the elastic fiber of the pleura. In these 5 cases, clinical courses were uneventful, and relapse of the pneumothorax did not occur. Clinical physicians should be aware of the possibility of asymptomatic pneumothorax, as well as the optimal radiographic techniques for revealing small pneumothoraces.

Adolescent↗

PubMed1999

[Incidence of asthmatic attack during anesthesia in patients with a history of bronchial asthma].

We investigated retrospectively, the incidence of intraoperative asthmatic attack in patients with bronchial asthma, and compared the past 5-year period (Jan 1, 1979 to Dec 31, 1983) and the recent 5-year period (July 1, 1990 to June 30, 1994). The influence of anesthetic methods, induction agents, and intervals between the most recent attack and anesthesia were evaluated. The incidence of the attack during anesthesia in patients with asthma was similar in both period, 6.7% in the past and 7.8% in the recent period. Patients who had a history of recurrent attacks within 2 years prior to anesthesia tended to have higher incidence of intraoperative attack in both periods. Furthermore, the incidence of asthmatic attack was significantly greater in patients receiving inhalational anesthetics for induction of anesthesia than in those given intravenous anesthetics in the recent period. Although inhalational anesthetics are considered to be used safely for asthmatic patients, care should be taken when volatile anesthetics are administered to asthmatic patients during induction of anesthesia.

Anesthesia, Inhalation↗

PubMed1999

[Coronary bypass surgery within thirty days of acute inferior myocardial infarction].

Between April 1988 and November 1998, 82 patients underwent isolated coronary artery bypass grafting within 30 days of acute myocardial infarction. The infarct-related artery was the proximal right coronary artery (27 patients; group 1) and the left coronary artery (55 patients; group 2). In group 2 the infarct-related artery was the left main coronary artery (8 patients), the left anterior descending coronary artery (33 patients), and the left circumflex coronary artery (14 patients). There was no difference between groups 1 and 2 with regard to sex, age (65 +/- 9 vs 66 +/- 10, respectively), presence of diabetes, renal insufficiency, previous myocardial infarction, and preoperative use of an intraaortic balloon pump (67% vs 71%, respectively). Compared with group 2, group 1 patients more often had three-vessel or left main disease (93% vs 65%, respectively; p = 0.018), a higher number of bypass grafts (3.0 +/- 0.8 vs 2.5 +/- 0.7, respectively; p = 0.014), and a greater incidence of postoperative complete atrioventricular (AV) block (30% vs 6%, respectively; p = 0.005). The hospital mortality rate for patients who underwent surgery within 48 hours after acute myocardial infarction did not differ between groups 1 and 2 (22% vs 18%, respectively). However, patients in both groups who underwent surgery between 48 hours and 30 days after infarction had significantly different mortality rates (22% vs 0%, respectively; p = 0.037). Patients with postoperative complete AV block had high mortality rates of 38% in group 1 and 67% in group 2. We conclude that patients who undergo coronary bypass surgery within 30 days of acute inferior myocardial infarction have a high incidence of postoperative complete AV block, which result in increased mortality.

Aged↗

PubMed1999

[Clinical experience with gelatin-resorcine-formol glue for repair of postinfarction ventricular septal rupture].

We report a surgical technique for treatment of postinfarction ventricular septal rupture (VSR). An 82-year-old woman underwent successful surgical repair of a VSR two days after suffering anterior myocardial infarction. After repair of the VSR with a Dacron patch, the left ventriculotomy was closed with mattress sutures over felt strips using the gelatin-resorcine-formol glue to reinforce the left ventricular wall. The patient was doing well four months after surgery.

Aged↗

PubMed1999

[Lung resection affects the postoperative arrhythmia and electrocardiographic axis deviation].

After lung lobectomy or pneumonectomy, the mediastinal shift and diaphragmatic elevation are occurred. Because this phenomenon may affect the heart positional change, we studied the electrocardiographic QRS axis in the frontal plane (from leads I and III) and the postoperative arrhythmia. Seventy three patients who had no heart disease including arrhythmia before the surgery were recorded their electrocardiogram (ECG) before their surgery and after their discharge. When the postoperative ECG was recorded, they had no respiratory failure nor cancer recurrence, and their lungs were fully expanded in their thoracic cages. After right upper lobectomy (19 cases), the axis was twisted rightward slightly (2.1 degrees). Right middle lobectomy (2 cases, 9.5 degrees) and right upper and middle lobectomies (3 cases, 7.3 degrees) twisted the heart axes more rightwards. Right lower lobectomy (12 cases, -1.0 degree) and right middle and lower lobectomies (3 cases, -17.7 degrees) contorted their axes leftwards and right pneumonectomy (5 cases, 31.4 degrees) rightwards. The axes were turned rightwards after the left upper lobectomy (18 cases, 2.8 degrees) and the left lower lobectomy (7 cases, 3.9 degrees). Left pneumonectomy (4 cases, -4.0 degrees) twisted the axis leftwards. After the surgery, arrhythmias were recorded in 14 cases and, among these patients, 5 cases were required the oral anti-arrhythmic medication. Most of these cases changed their heart axes after the surgery and it is suggested that the axial deviation may contribute to their postoperative arrhythmia.

Arrhythmias, Cardiac↗

PubMed1999

[Angiographically occult high cervical dural arteriovenous malformation secondary to intracranial hypertension: a case report].

We have recently encountered a case of high cervical arteriovenous malformation which caused subarachnoid hemorrhage. A 54-year-old male was admitted to our hospital due to sudden onset of severe headache. Neurological examination revealed right sixth nerve palsy which suggested elevated intracranial pressure. A CT scan showed subarachnoid hemorrhage predominantly in the posterior fossa, massively ventral to the brain stem, with reflux into the fourth ventricle. No abnormal vascular lesions were found in the first cerebral angiography which included four vessels and bilateral thyrocervical trunks. Ten days later, the second cerebral angiography demonstrated an arteriovenous shunt via the right vertebral artery draining into the epidural space of the upper cervical region. A suboccipital craniotomy and laminectomy of the atlas were performed. An abnormally dilated vein along the right C1 nerve ventral root which drained into the tortuous dilated coronary venous plexus on the ventral side of the spinal cord was found. We made a diagnosis of dural arteriovenous malformation fed by the C1/C2 radicular artery via the right vertebral artery and draining into the radiculomedullary vein and the epidural venous plexus. The interruption of both intra- and extradural draining veins was carried out. The postoperative course was uneventful.

Arteriovenous Malformations↗

PubMed1999

Eosinophil activation in the tissue: synthetic steroid, budesonide, effectively inhibits the survival of eosinophils isolated from peripheral blood but not nasal polyp tissues.

We investigated the effect of a potent synthetic steroid, budesonide (BUD), on the survival of nasal polyp (NP) derived eosinophils (EOS). BUD, at the highest dose used, 10(-6) M, decreased this survival but only by approximately one third. We speculated that the relatively small inhibitory effect of budesonide on the survival of NP-EOS could be the result of these EOS being exposed to substantial amounts of GM-CSF, IL-5 or IL-3. In this regard, we detected 148 pg of GM-CSF per 150 mg of tissue, which approximately contained 106 of eosinophils, in the supernatant of NP explants for 24 h without any stimulation. Contents of both IL-5 and IL-3 were much less. We further studied survival of PB-EOS exposed to rhGM-CSF and found that 10(-6) M of BUD could only inhibit by less than one third the survival of PB-EOS exposed to an amount of rhGM-CSF, similar to that detected in the supernatant of NP explants. In addition, we exposed PB-EOS to 200 pg/ml of rhGM-CSF for a relatively long period of time (4 days) in order to mimic chronic exposure in the tissue and found that the survival of these cells was prolonged to the extent similar to that observed in NP-EOS. Our data suggests that the prolonged spontaneous survival of NP-EOS ex vivo is likely the result of sustained in vivo exposure to GM-CSF and budesonide has a smaller inhibitory effect in the survival of these eosinophils as compared to those from peripheral blood.

Administration, Topical↗

PubMed1998

Two diverged complement factor B/C2-like cDNA sequences from a teleost, the common carp (Cyprinus carpio).

Mammalian complement components factor B and C2 act as proteolytic subunits of the C3 convertases in the alternative and the classical activation pathways, respectively, and are believed to have diverged from a common ancestor by gene duplication. However, it is unclear when the B/C2 duplication occurred. Here, we describe two diverged B/C2-like cDNA clones (B/C2-A and B/C2-B) isolated from a bony fish, the common carp (Cyprinus carpio). B/C2-A shares the same domain structure as the factor B and C2 complement components of vertebrates reported so far and shows a close similarity to zebrafish B and medaka fish B/C2. These teleost sequences show almost the same degree of similarity to C2 and B of higher vertebrates. In contrast, B/C2-B has a novel structural feature in that it contains four short consensus repeat modules and does not have a close relative upon phylogenetic analysis. Northern blotting revealed the presence of two transcripts with different sizes for both the B/C2-A and B/C2-B in the hepatopancreas of the carp. Southern blotting suggested the presence of multiple genes for B/C2-A and a single gene for B/C2-B. Although structural features of B/C2-B are slightly more C2-like than B-like, B/C2-B has a crucial amino acid substitution in the serine protease domain, which makes it unlikely that B/C2-B functions as a C3 convertase. A possible phylogenetic relationship between the two carp sequences and mammalian C2 and B is discussed.

Amino Acid Sequence↗

PubMed1998

Two lineages of mannose-binding lectin-associated serine protease (MASP) in vertebrates.

Mannose-binding lectin-associated serine protease (MASP) is a newly identified member of the serine protease superfamily. MASP is involved in host defense against pathogens through a novel system of complement activation, designated the lectin pathway. To elucidate the origin of the lectin pathway and the molecular evolution of MASP, we cloned six MASP cDNAs from five vertebrate species going from mammal to cyclostome. An alignment of the amino acid sequences deduced from the cDNAs revealed the presence of two different lineages of the MASP gene. This classification was supported by the precise correlation with two types of exon organization for the protease domain. One of the two lineages is unique in that a single exon encodes the protease domain, unlike most other serine proteases. All members of this group, termed the AGY type, have an AGY codon at the active site serine. A phylogenetic tree suggests that the AGY type diverged from another lineage, termed the TCN type, before the emergence of primitive vertebrates. Furthermore, the presence of MASP or MASP-like sequences in most vertebrate species suggests that the lectin pathway functions extensively in vertebrates and that its origin is traced back to the invertebrate stage.

Amino Acid Sequence↗

PubMed1998

Changes in brain organic osmolytes in experimental cerebral ischemia.

The cell volume is regulated not only by inorganic ions, but also by organic osmolytes, such as amino acids, methylamines, and polyhydric alcohols (polyols). Using proton nuclear magnetic resonance spectroscopy (1H-NMR), we measured the tissue concentrations of amino acids (alanine, aspartate, gamma-aminobutyric acid (GABA), glutamate, glutamine, N-acetyl-aspartate (NAA), taurine), methylamines (glycerophosphorylcholine (GPC), creatine+phosphocreatine (total creatine, tCr)), and polyols (myo-inositol) in the rat brain after middle cerebral artery occlusion (incomplete focal ischemia) or after decapitation (complete global ischemia). The total osmolytes expressed as a sum of total amino acids, total methylamines, and total polyols were significantly decreased at 24 h of focal ischemia (58.7% of control value, P=0.0025) whereas they were not changed following decapitation. The water content was increased from control value of 77.9%-84.1% after focal ischemia (P<0.0001) but not after decapitation. These results suggest that the brain organic osmolytes are involved in the process of edema formation following focal cerebral ischemia. Further elucidation of the cellular mechanisms regulating these organic osmolytes in cerebral ischemia may promote greater understanding of the pathophysiology involved in the evolution of brain edema.

Alanine↗

PubMed1998

Increased transcription of glutamate-aspartate transporter (GLAST/GluT-1) mRNA following kainic acid-induced limbic seizure.

Expression of mRNA for glutamate-aspartate transporter (GLAST/GluT-1/EAAT1) was studied in the brain of the rat which presented recurrent limbic seizure following systemic administration of kainic acid (KA) by in situ hybridization and Northern blot analysis. The expression of GLAST mRNA was markedly increased after 12 h and peaked after 48 h in animals which demonstrated limbic seizure. The induction of the mRNA were observed in the small non-neuronal cells in the hippocampus, especially around CA3 region and hilus. In contrast, there was no change in GLAST mRNA levels in KA injected seizure-free animals. These findings suggest that GLAST mRNA is induced by seizure and increased extracellular glutamate levels during seizure may be important for induction of GLAST mRNA.

ATP-Binding Cassette Transporters↗

PubMed1998

Expression of MHC class Ia and class Ib during ontogeny: high expression in epithelia and coregulation of class Ia and lmp7 genes.

The amphibian Xenopus permits the examination of immune responses in a species that progresses through two distinct lives, tadpole and adult, in which animals are free-living and immunocompetent. MHC gene expression as well as general features of the immune system change profoundly at metamorphosis. In this study gene expression of class Ia, class Ib, and the immune proteasome component lmp7 was investigated by Northern blotting at all stages of development. Class Ia genes are expressed in most adult tissues, with highest levels in intestine. Class Ib genes are expressed at lower levels, and their tissue distribution is somewhat more restricted than that of class Ia. Consistent with the idea that particular class Ib isotypes can perform distinct functions, preferential expression of class Ib genes is found in some tissues, with one family being expressed exclusively in epithelia. The onset of MHC expression is not simultaneous in all tissues: class Ia transcripts are first present in tadpole lung, gill, and intestine, organs with epithelial surfaces in contact with the environment. In every tissue except colon and muscle, class Ia expression increases markedly after metamorphosis. Interestingly, expression of the MHC-linked proteasome component lmp7 mirrored class Ia expression, while the constitutive lmp7 homologue X was expressed ubiquitously at all stages. Class Ib transcripts were never detected before metamorphosis, suggesting that the Xenopus class Ib proteins identified to date do not subserve class Ia functions in tadpole life.

Animals↗

PubMed1998

Functional differences among multiple isoforms of guinea pig decay-accelerating factor.

Decay-accelerating factor (DAF, CD55) is a membrane inhibitor that protects host cells from the autologous C-mediated attack. The guinea pig homologue of DAF consists of multiple isoforms generated by alternative splicing from a single copy gene. These isoforms are mainly comprised of a glycosylphosphatidylinositol (GPI)-anchored form and a transmembrane form (TM) that is not present in human DAF. Both forms occur in at least three variations that differ in the length of the Ser/Thr-rich region (termed ST-a, ST-ab, and ST-abc). We have transfected cDNAs of the six major isoforms into Chinese hamster ovary cells, and their functional differences were evaluated in inhibition of C-mediated cytolysis and C3 deposition, using the transfectants expressing DAF at the same level on cell membranes. The degree of inhibition in both the classical and alternative pathways differed according to the length of the ST region in the order of abc > ab > a in both GPI and TM forms. When GPI and TM forms were compared, those with the ab or abc variation exhibited almost the same activity, whereas a-TM was less efficient than a-GPI. Although several isoforms are expressed constitutively in most of tissues, spermatozoa preferentially express the abc-GPI isoform, suggesting that this isoform offers effective protection to spermatozoa in the female genital tract.

Animals↗

PubMed1998

Post-meiotic expression of the mouse dihydropyrimidinase-related protein 3 (DRP-3) gene during spermiogenesis.

The dihydropyrimidinase-related protein (DRP) family, originally identified in humans by their homology to dihydropyrimidinase, contains at least four members. Genes of this family, and their counterparts in other mammals and chickens, are expressed mainly in fetal and neonatal brain, suggesting that the encoded proteins have a physiological role in the development of the central nervous system. In addition, the DRP-3 gene is expressed in testis as a shorter mRNA than the brain form. As a first step in understanding the extra-neuronal function of DRP-3, the structure and expression of testis DRP-3 were examined. Testis DRP-3 cDNA showed the same sequence as brain DRP-3 cDNA, except for the 5'-terminal end, which encodes a 5'-untranslated region and the 11 N-terminal amino acid residues, indicating that the two forms of DRP-3 mRNA were transcribed from a single copy gene. Northern blotting analysis detected DRP-3 mRNA in 30-, 40- and 70-day-old, but not in 10- and 20-day-old testes. In situ hybridization analysis indicated that the expression of DRP-3 in testis is restricted to post-meiotic round spermatids. This is the first report of the expression of DRP genes in extra-neuronal cells.

Amino Acid Sequence↗