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T Tamiya

Publications and source records attributed to T Tamiya.

At least 19 recordsLinked to original sources
PubMed1992

Molecular cloning of the antibacterial protein of the giant African snail, Achatina fulica Férussac.

An expression cDNA library was constructed with poly(A)-rich RNA extracted from the collar of the giant African snail, Achatina fulica Férussac. A 1.9-kbp cDNA clone encoding a precursor of antibacterial glycoprotein of the snail, achacin, was isolated from the cDNA expression library. The cDNA sequence contains an open reading frame with 1593-nucleotide residues. The deduced amino acid sequence of this achacin precursor starts with a 29-residue leader peptide followed by a 502-residue mature peptide (56 kDa) with four possible N-glycosylation sites, Asn-Xaa-Ser or Asn-Xaa-Thr. The Northern-blot analysis proved that the achacin precursor was specifically expressed in the tissue of snail collar and processed to mature achacin. cDNA inserts encoding achacin precursor were subcloned into expression plasmids. Three kinds of expressed polypeptides were cross-reacted with rabbit antiserum raised against achacin. The largest polypeptide (M(r) 63,000) should be the achacin precursor.

Amino Acid Sequence↗
PubMed1992

Electrophysiologic study of dysrhythmias after atrial operations in dogs.

Experiments were conducted with 159 dogs to investigate the mechanism of persistent dysrhythmias clinically encountered after atrial-level operations. Those found after incisions to the internodal pathways (INPs) of the right atrium were analyzed using cardiac mapping in an anesthetized or extracorporeally perfused state. Longitudinal incisions of the posterior INP often allowed inducible sustained atrial flutter, with circus movement of excitation around the right atrium near the tricuspid orfice. Sustained atrial flutter thus produced was modified in cycle length by coexisting division of the middle INP but inhibited by that of the anterior INP. Its incidence increased at chronic stage, with marked cicatricial changes. The disrupted anterior INP markedly prolonged conduction time to the atrioventricular node and A-H interval compared with the other disruptions. Persistent atrioventricular junctional rhythm developed in about 50% of the animals after disruption of all three INPs or anterior and posterior INPs; division of the anterior INP was the common potent factor, although no single blocked INP produced persistent junctional rhythm. Our results support the "summation theory." The incidence of junctional rhythm and hypoxia of the sinoatrial node (flow rate of less than 10 mL.100 g-1.min-1) were markedly enhanced by coexisting blockade of atrial feeding arteries in addition to division of the anterior INP. In conclusion, massive posterior INP disruption is a potent anatomic substrate in producing sustained atrial flutter, middle INP division a modifier, and anterior INP division an inhibitor. Division of the anterior INP is a potent anatomic substrate in producing junctional rhythm, and hypoxia involving the sinoatrial node reacts as its synergic factor.

Animals↗
PubMed1992

Bactericidal action of a glycoprotein from the body surface mucus of giant African snail.

1. Bactericidal action of a glycoprotein, Achacin, purified from the giant African snail, Achatina fulica Férussac, has been studied. 2. Achacin kills both gram-positive and gram-negative bacteria, but only in their growing states. 3. Achacin does not have any bacteriolytic activity. 4. The strain which has no cell wall is a little more sensitive than the native strain and the cell membrane-damaged strain. 5. Achacin was observed on the cytoplasmic membrane and on the cell wall of treated Escherichia coli by immunoelectron microscopy. 6. Achacin attacks the cytoplasmic membrane of the cell.

Animals↗
PubMed1992

Significance of the concentrated red cell and albumin priming method with particular reference to anaphylatoxin generation.

Anaphylatoxins generated by cardiopulmonary bypass were observed in basic and clinical studies (n = 120 in the latter). In vitro immunoglobulin fractions denatured by oxygen bubbling produced C4a, C3a, and C5a, but albumin identically treated did not. Therefore concentrated red cells with albumin were used to prime homologous blood for clinical application during cardiopulmonary bypass. Complement levels were compared with type of oxygenator (bubble or membrane) and the ratio of primed homologous blood to circulating autologous blood volume. With the bubble oxygenator at a low ratio of homologous to autologous blood (arbitrarily defined as less than 20%), C3a levels during cardiopulmonary bypass tended to be lower in the concentrated red cells plus albumin priming group than in the ordinary priming group (p less than 0.1, at 60 and 90 minutes of cardiopulmonary bypass). C4a and C3a levels increased less after protamine administration with concentrated red cells plus albumin priming (p less than 0.05, p less than 0.01, respectively, 90 minutes after protamine) than with ordinary priming. Such changes in the membrane oxygenator group were less remarkable. Thus C3a levels were approximately the same in both oxygenator groups primed with concentrated red cells plus albumin. The higher the homologous to autologous ratio, the steeper the C4a and C3a increase from the beginning of cardiopulmonary bypass with the bubble oxygenator. This tendency was less remarkable in the membrane oxygenator group. Early postoperative pulmonary function was improved by concentrated red cells plus albumin priming, especially in the bubble oxygenator group. In conclusion, (1) oxygenator systems primed with concentrated red cells plus albumin produced less anaphylatoxin than those with homologous blood, especially with the bubble oxygenator, and (2) our clinical results support the importance of immunoglobulin denatured by oxygen bubbling in anaphylatoxin generation (by means of the classical pathway), as shown by our in vitro study.

Anaphylatoxins↗
PubMed1991

[Roles of the sympathetic nervous system in the local release of vasoactive intestinal polypeptide (VIP) from the small intestine of anesthetized dogs].

To investigate roles of the sympathetic nervous system in the local release of VIP, pharmacological alpha (phenoxybenzamine), beta (propranolol) adrenergic blockade or surgical sympathectomy by the ganglionectomy of splanchnic plexus was performed in anesthetized dogs. Portal and venous plasma VIP levels during intrajejunal infusion of 0.1 N HCl solution at a rate 1.5 ml/min for 20 minutes were observed before and after these procedures. The plasma VIP levels during the intrajejunal HCl infusion were significantly increased after blocking of alpha-adrenoceptors and surgical sympathectomy but showed no change after blocking of beta-adrenoceptors. These results suggest the inhibitory mechanism of the sympathetic nervous system on the local release of VIP from the canine small intestine. In addition, the increase of portal blood flow and bile secretion, and the elevation of bicarbonate concentration in the secreted bile during the intrajejunal HCl infusion were significantly higher after surgical sympathectomy than before, and plasma VIP levels were also significantly higher.

Anesthesia↗
PubMed1991

[A case of right ventricular hemangioma].

We report a case of right ventricular hemangioma which is extremely rare. It was situated on the anterior wall of the right ventricle and protruded into the out flow tract. Aortography revealed that the main feeding artery was the conus brunch. Operation was done under cardiopulmonary bypass. The tumor was situated between LAD and RCA and resected incompletely, because of the fear that complete removal would occlude blood flow of both LAD and RCA. Histological examination disclosed intramuscular hemangioma. The postoperative course was uneventful. To our knowledge, this is the second resected case in the Japanese literature and the eighth case in the world literature.

Adult↗
PubMed1990

Structure of the snake short-chain neurotoxin, erabutoxin c, precursor gene.

A 2.4-kb genomic clone, which encodes the precursor of a snake neurotoxin, erabutoxin c, was isolated from the liver of the sea snake, Laticauda semifasciata. The erabutoxin c gene is about 1.2 kb long and consists of three exons and two introns. The first intron is found at the position corresponding to the signal peptide between amino acid residues 18(Leu) and 19(Gly). The second intron is located at the position corresponding to the central loop of the mature toxin, between amino acid residues 33(Arg) and 34(Gly). A TATA box consensus sequence, characteristic of promoter regions, is identified 29-33 nucleotides upstream from the transcription-initiation site identified by nuclease S1 analysis. The erabutoxin c cDNA nucleotide sequence, deduced from the present work, is compared with the cDNA sequences of erabutoxins a and b reported previously. Replacements are found at three positions, two of which correspond to the amino acid replacements found among the toxins, while the other is silent.

Amino Acid Sequence↗
PubMed1990

Detection of a fast isoform of C-protein with an antiserum directed against the N-terminal portion of dystrophin.

An antiserum raised against the N-terminal actin-binding portion of dystrophin cross-reacted with a 130-kDa protein in fast skeletal muscle. The results of purification and two-dimensional gel electrophoresis and its immunological properties demonstrated that this protein is identical to a 130-kDa basic isoform of fast-C-protein. These results suggest that the actin-binding domain of dystrophin shares one or more antigenic determinants with those of C-protein.

Antibodies↗
PubMed1990

Central neurocytoma--case report.

The authors present a case of central neurocytoma in a 34-year-old female who had experienced intermittent headaches over a 10-year period. On computed tomographic (CT) scans and magnetic resonance images, the tumor appeared as a large, calcified mass occupying both lateral ventricles. A right parieto-occipital craniotomy was performed and the tumor was totally removed. While the light microscopic findings suggested a diagnosis of oligodendroglioma, electron microscopic examination demonstrated clear vesicles, microtubules, and synaptic structures within the abundant cytoplasmic processes of the tumor cells. Immunohistochemical examination showed the tumor cells to be strongly positive for neuron-specific enolase, sparsely positive for S-100 protein, and negative for glial fibrillary acidic protein. The final histological diagnosis was central neurocytoma. The postoperative course was uneventful and no further treatment was administered. She has no neurological deficits and CT has shown no evidence of recurrence during the 2 years since her surgery. Central neurocytoma is a rare tumor arising in the lateral ventricle, and the diagnosis is mainly based on electron microscopic findings. Since central neurocytoma appears to have a good prognosis following total removal alone, it is very important to distinguish between this and other ventricular tumors.

Adult↗
PubMed1990

[A case report of coronary artery fistula into the left ventricle].

Communication of the right coronary artery with the left ventricle is considerably rare. We report a case of congenital fistula of the left ventricle. Closure of the fistula was successfully done by Symbas' modification. Thirty cases with coronary artery fistula to the left ventricle reported in Japanese literatures, including our case were reviewed in regard to its surgical treatment.

Adult↗
PubMed1989

Effect of chemical modifications on freeze denaturation of lactate dehydrogenase.

Lactate dehydrogenase (LDH) was chemically ethyl-acetimidated (EA-), dimethyladipimidated (DMA-), carbamylated, acetylated, acetoacetylated, or succinylated in order to alter the ionic charges on the epsilon-amino group of lysine residues. Acetylation, acetoacetylation, and succinylation, which change the positive charge at the lysine side chains to a negative one, inactivated the enzymic activity, but the rest of the modifications exerted no such inactivating effects. The active modified enzymes were subjected to freeze denaturation study, using the enzymic activity as an indication of the degree of the denaturation. The active enzymes were diluted with deionized water and stored in a freezer (-23 degrees C) for 1-3 days. Enzymic activity was assayed immediately after thawing. All the modified enzymes retained their activity even after the 3-day frozen storage, while the control or native enzyme lost its activity within 1 day of storage. Furthermore, the modified LDHs freeze-stored in 0.2 M monosodium glutamate (MSG) or 0.2 M lysine-hydrochloride (Lys-HCl) retained their activity. The cryoprotective effects exerted by the modifications and by 0.2 M MSG seemed to be synergistic, whereas those exerted by the modifications and by 0.2 M Lys-HCl did not. The mechanisms of cryoprotection and freeze denaturation are discussed in relationship with the cryoprotective effect exerted by already known cryoprotectants, such as sucrose or dimethyl sulfoxide.

Animals↗
PubMed1989

Coagulation and fibrinolysis in chronic subdural hematoma.

In 19 patients with chronic subdural hematoma, coagulation and fibrinolysis in venous blood taken at the time of surgery and in the hematoma contents aspirated from chronic subdural hematoma were studied. Compared with coagulation results for venous blood, the hematoma contents demonstrated marked prolongation of the recalcification time, prothrombin time, and activated partial thromboplastin time, and marked reduction of clotting factor V, the hepaplastin test, prothrombin, and fibrinogen. Antithrombin III was also decreased, and fibrinopeptide A was increased in the hematomas. Fibrinolytic results demonstrated that both plasminogen and alpha 2-plasmin inhibitor were decreased, and both fibrinopeptide B beta 15-42 and fibrin and fibrinogen degradation products were increased in the hematomas. These findings indicate excessive activation of the clotting system, thrombin generation, and increased fibrinolytic activity occurring in the hematomas. From these results, excessive activation of both the clotting and fibrinolytic systems is emphasized to be the possible etiological factor for the origin and development of chronic subdural hematoma.

Adult↗
PubMed1989

[Experience with surgical therapy in ventricular septal perforation following acute myocardial infarction, with special reference to operative method].

Repair of ventricular septal perforation (VSP) caused by acute myocardial infarction (AMI) has been one of the unsettled subjects in cardiac surgery, because of high mortality. Our patients operated on for VSP during approximately the past 3 1/2 years consisted of five with anteroseptal infarction and one with inferoseptal infarction. Of the former five, four underwent sandwich procedure and one, ventriculoplasty for extensive lesions. The inferoseptal infarction case was treated initially with simple ventricular closure, but subsequently with ventriculoplasty for postoperative false ventricular aneurysm. Operative mortality rate, i.e., within one month was 17%, but the final survival rate was 50% for delayed complications. Various reparative methods were applied. Our impression thus far obtained is as follows. Sandwich procedure should be best for anteroseptal cases unless lesions are extensive, but ventriculoplasty should be of the choice for infero-(or postero-) septal cases or extensive anteroseptal cases. Our reparative method devised to improve closure of VSP is also introduced.

Aged↗