Search PubMed⌕ Search

Biomedical subjects

Y Takada

Publications and source records attributed to Y Takada.

At least 703 records · Page 39Linked to original sources
PubMed1981

Circular myotomy and esophageal length and safe esophageal anastomosis: an experimental study.

The indication for circular myotomy is often unclear at the time of esophageal atresia repair because the maximal permissible tension at the anastomosis and the precise effect of myotomy on esophageal length and anastomotic tension are not known. This study was undertaken to answer these questions. In piglets, 0 to 6.5-cm segments of thoracic esophagus were excised and approximation force was measured by dynamometers attached to traction sutures in each cut end of the esophagus prior to anastomosis. When approximation force was greater than 75 g. esophageal leaks occurred and increased fibrosis was noted at the anastomosis. Circular myotomy of the upper segment reduced the force necessary to approximate the ends of the esophagus after a 5- to 6-cm resection by about 50%, and double circular myotomy by as much as 75%. When the upper third of the esophagus of piglets and neonatal cadavers was stretched by the application of traction forces of 0 to 75 g. esophageal length increased by about 40%. Thereafter, length increase ws minimal. For any given traction force, each circular myotomy increased esophageal length by about 5 mm. These studies suggest that accurate measurement of approximation force would be useful at the time of esophageal atresia repair. On the basis of these data, circular myotomy(s) is indicated to elongate the esophagus and reduce anastomotic tension when a force greater than 75 g is needed to approximate the esophageal ends.

Animals↗
PubMed1981

Presence of guanosine 5'-diphosphate 3'-diphosphate in Bacillus subtilis vegetative cells.

Extracts of Bacillus subtilis vegetative cells with 2 M formic acid contained a large amount of a hyperphosphorylated nucleotide ("spot 4" nucleotide). The compound always comigrated with authentic guanosine 5'-diphosphate 3'-diphosphate (ppGpp) on two-dimensional polyethyleneimine (PEI)-cellulose thin-layer chromatography performed with three different solvent systems. Furthermore, all dephosphorylated 32P-labeled derivatives from the "spot 4" nucleotide comigrated on a one-dimensional PEI-cellulose plate with those from authentic ppGpp present in the same reaction mixture, when the compounds were hydrolyzed with snake venom phosphodiesterase or alkali. The level of the "spot 4" nucleotide (ppGpp) in the cell extracts was 0.14 nmol P/A660, corresponding to about one-third of the guanosine 5'-triphosphate (GTP) level and about 10% of the adenosine 5'-triphosphate (ATP) level. These results indicate that a "magic spot" nucleotide, ppGpp, is present at a high level in B. subtilis cells vegetatively growing in mNSMP.

Bacillus subtilis↗
PubMed1981

Isolation and characterization of angiotensin converting enzyme from human kidney.

Angiotensin converting enzyme [EC 3.4.15.1] was solubilized from the membrane fraction of human kidney cortex using trypsin and purified to homogeneity by DEAE-cellulose, hydroxylapatite and DEAE-Sephadex A-50 column chromatographies, preparative isoelectric focusing, and Sephadex G-200 gel filtration. The final recovery of the enzyme was 13.9%. The molecular weight of the enzyme was estimated to be 199,000 by a sedimentation equilibrium method. A value of 170,000 was obtained for the reduced and denatured enzyme by dodecylsulfate-polyacrylamide gel electrophoresis. The enzyme was a glycoprotein consisting of a single polypeptide chain with an isoelectric point of 5.10. Neutral sugar accounted for 13% per weight of the enzyme. The purified enzyme had a specific activity of 96.9 mumol/min/mg protein for hippurylhistidylleucine. The Km value, Kcat value and hydrolytic coefficient (Kcat/Km) of the enzyme for hippurylhistidylleucine were 2.0 mM, 545 s-1 and 273 mM-1 . s-1, respectively. Rabbit antibody against the human kidney converting enzyme inhibited the activities of the enzymes from human lung and serum as equally as that from human kidney, but not those from sheep, dog, or rat sera. The human kidney and lung converting enzymes were immunologically identical on double immunodiffusion analysis.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1981

[Studies of fertilizing capacity of spermatozoa from infertile men with oligozoospermia. AIH by washed and concentrated spermatozoa and in vitro fertilizing capacity to zona free hamster eggs (author's transl)].

The fertilizing abilities of spermatozoa from infertile men with oligozoospermia were evaluated by examining pregnancy rates after AIH using washed and concentrated spermatozoa, and also by in vitro fertilizing rates to zona free hamster eggs. The spermatozoa from ten oligozoospermic men with less than 20 x 10(6)/ml of sperm counts were used in the experiments. After the procedures of washing and concentrating spermatozoa from oligozoospermic men, the sperm concentration was increased from two to six times and the sperm motility was also increased up to two times. However none of the patients' wives conceived after several AIHs with washed and concentrated spermatozoa. When the in vitro fertilization of zona free hamster eggs by the spermatozoa was used, the fertilization rates were null in case of 7 oligozoospermic patients, and 5, 10 and 33.3% in case of another 3 oligozoospermic patients respectively in contrast with 73.3% in use of spermatozoa from control fertile men. The fertilizing abilities of spermatozoa from husbands of 4 sterile couples with an unknown cause were examined by in vitro fertilization test and 7.1, 37.5, 50.0 and 55.6% fertilization rates were obtained. Among these men, the spermatozoa from one man indicated a very low fertilization rate without any other pathological findings. This suggests that the impairment of fertilizing ability of spermatozoa might be present in the case of sterile men with an unknown cause.

Adult↗
PubMed1981

[Comparative studies on doses of complement for detection of sperm immobilizing antibody in serum, cervical mucus and seminal plasma (author's transl)].

In Isojima's sperm immobilization test, the complement is one of the most important factors which influence on sensitivity of the test. Previously we reported that more than 10 CH50 of guinea pig serum complement was necessary in the reaction to obtain the best result for measuring the sperm immobilizing antibody in the serum. This time, the influences of various test specimens on complement activities for the sperm immobilization test were studied and the necessary amounts of complement to detect the sperm immobilizing antibody in serum, cervical mucus and seminal plasma were compared. In the sperm immobilization test, the following results were obtained: 1. The amount of complement (guinea pig serum) added was 11.9 CH50, and after 60 minutes incubation at 32 degrees C in veronal buffer (VB2+), 2.0 +/- 0.3 (M +/- SD) of CH50 was consumed. 2. When human serum, cervical mucus and seminal plasma were added to the reaction as specimens, the complement consumptions (M +/- SD) were more 0.2 +/- 0.3 CH50, 0.2 +/- 0.2 CH50 and 3.3 +/- 0.8 CH50 than that of VB2+ buffer respectively. 3. When the washed human spermatozoa were added, the consumed amounts of complement (M +/- SD) were dose dependent; 3.5 +/- 0.7 CH50 for 100 X 10(4) spermatozoa, 7.3 +/- 0.3 CH50 for 200 X 10(4) spermatozoa and 15.7 +/- 2.2 CH50 for 400 X 10(4) spermatozoa. 4. In our sperm immobilization test, the net consumptions of complement (M +/- SD) were 5.0 +/- 0.7 CH50 for specimen of serum, 4.9 +/- 0.8 CH50 for specimen of cervical mucus and 11.1 +/- 1.2 CH50 for specimen of seminal plasma. 5. Complement doses necessary to obtain the most sensitive sperm immobilization tests were 10 CH50 for both serum and cervical mucus specimens, and 15 CH50 for seminal plasma specimen.

Animals↗
PubMed1980

The appearance of a new aromatic aminotransferase in the small intestines of vitamin B6-deficient rats.

Vitamin B6 deficiency led to a decrease in aspartate: 2-oxoglutarate aminotransferase activity and to a marked increase in phenylalanine:2-oxoglutarate aminotransferase activity in rat small intestines. The increased phenylalanine aminotransferase activity was found to be due to a newly appeared aromatic aminotransferase without the aspartate aminotransferase activity in the cytosol of the small intestinal mucosa. The enzyme preparation had an isoelectric point of pH 8.5, a pH optimum near 8.0, and a molecular weight of approximately 100,000 with two identical subunits. The enzyme showed aminotransferase activities towards various aromatic L-amino acids with 2-oxoglutarate as the amino acceptor. The order of effectiveness of aromatic L-amino acids was phenylalanine > tryptophan > tyrosine > 5-hydroxytryptophan; very little activity was detected with other L-amino acids that were tested. The enzyme was specific for 2-oxoglutarate as the amino acceptor. The enzyme was not detected in other tissues (liver, kidney, heart, and brain) from both control and vitamin B6-deficient rats. The enzyme has never been described before in animal tissues.

Animals↗
PubMed1980

Interaction of plasmin with tranexamic acid and alpha 2 plasmin inhibitor in the plasma and clot.

Interaction of urokinase (UK) activated plasmin with tranexamic acid and alpha 2 plasmin inhibitor (alpha 2PI) was studied by using a chromogenic substrate (S-2251) and immunoelectrophoresis. Plasma was activated by UK (P + U) in the presence of tranexamic acid (P + U + t) or in the presence of thrombin (P + U + thr) and thrombin plus tranexamic acid (P + U + thr + t). These mixtures were incubated for 10, 20, and 30 min at 37 degrees C, then an aliquot of each mixture was added to S-2251, and incubated for 3 or 10 min at 37 degrees C. Hydrolysis of S-2251 after 3 min incubation was significant in the presence of tranexamic acid or clot formation, thus the presence of tranexamic acid or clot formation enhancing the UK activation of plasminogen in both plasma and clot. Hydrolysis of S-2251 after 10 min incubation was higher in the presence of tranexamic acid than in its absence or clot formation without tranexamic acid. Tranexamic acid seems to be more effective in enhancement of activation of plasminogen by UK than clot formation. Plasmin formed by UK was coexistent with alpha 2PI in the plasma in contrast to a purified system in which alpha 2PI formed a complex with plasmin instantaneously. In an even purified system, clot formation and the presence of tranexamic acid protected plasmin from its inactivation by alpha 2PI to some extent.

Blood Coagulation↗
PubMed1980

Serum intralipid levels in neonates during parenteral nutrition: the relation to gestational age.

To detect hyperlipidemia, serum Intralipid levels have been monitored by nephelometry (light scanning index) in children on total parenteral nutrition with glucose, amino acids, and Intralipid during the past 2 yr. Sufficient data were available in 93 neonates to analyze the effect of an Intralipid dose on serum levels in infants of different gestational ages. Guided by monitoring, Intralipid was given by constant infusion at a dose varying between 0.5 to 6.0 g/kg/day. Median post natal age at the start of therapy was 7 days. Gestational age varied from 27 to 32 wk in 36 infants (Group I), 33 to 36 wk in 18 (Group II), and was more than 37 wk in 39 (Group III). Of Group I infants, 28% developed hyperlipidemia (Intralipid level greater than 100 mg/100 ml) as compared to an incidence of 7% in Groups II and III. Peak Intralipid levels were highest in Group I and regression analysis also indicated that Intralipid was least well tolerated by this group. The dose response during the first 48 hr of Intralipid therapy was not significantly different from dose response later. Similarly, diagnosis did not seem to affect the dose-response. Dose recommendations were based on analysis of dose response lines. Even using these guidelines monitoring of serum Intralipid is advisable to avoid hyperlipidemia during Intralipid therapy. It is recommended that measurements of serum Intralipid be made several times per week in very low birth weight infants (Group I), and weekly in more mature neonates after a safe maximum Intralipid dose is established.

Age Factors↗
PubMed1979

Influence of coagulation on the activation of plasminogen by streptokinase and urokinase.

Human plasma was mixed with Ca++ or thrombin, and urokinase (UK) or streptokinase (SK) and a chromogenic substrate (S-2251: H-D-Val-Leu-Lys-pNA) specific to plasmin. The hydrolysis of S-2251 was higher when clot was formed by the addition of Ca++ or thrombin than in the absence of clot. The hydrolysis of S-2251 by euglobulin in the presence of UK was also higher when clot was formed, thus, inhibitors may not be related to the better activation of plasminogen, in the presence of fibrin clot. It may be suggested that plasminogen was better activated by activators (UK and SK) in the clot than in its absence.

Blood Coagulation↗