Biomedical subjects

Y Sai

Publications and source records attributed to Y Sai.

86 records · Page 5Linked to original sources

PubMed1992

Small GTP-binding proteins on rat liver lysosomal membranes.

GTP-binding proteins have been identified on the membranes of highly purified dextran-filled lysosomes (dextranosomes) and Triton-filled lysosomes (tritosomes) obtained from rat liver. Autoradiography of blots of lysosomal membrane proteins incubated with [alpha-32P]GTP revealed the presence of several specific GTP-binding proteins with a relative molecular mass (M(r)) predominantly in the range of 26-30 kDa. These GTP-binding proteins migrated slower in polyacrylamide gels than purified c-Ha-ras protein expressed in E. coli, whose apparent M(r) was 23 kDa in the same blot. The relative contents of GTP-binding proteins in lysosomal membranes were comparable or greater than that of plasma membranes and of microsomes. Chemical extraction showed that lysosomal GTP-binding proteins were more tightly associated with the membranes than with microsomal GTP-binding proteins. The possible involvement of lysosomal GTP-binding proteins in cellular functions including vacuolar (lysosomal) acidification and organellar dynamics are discussed.

Animals↗

PubMed1992

Three types of membranous ATPase on rat liver lysosomes.

At least three types of vanadate-insensitive membranous ATPase were identified on rat liver lysosomes: bafilomycin A1-sensitive Mg(2+)-ATPase (H(+)-ATPase), N-ethylmaleimide (NEM)-sensitive but bafilomycin A1-insensitive Mg(2+)-ATPase (ATPase I), and NEM-insensitive Ca2+/Mg(2+)-ATPase (ATPase II). They showed different sensitivity to chemicals and ions with apparent molecular masses of 700-800, 500-650, and 360 kDa, respectively. Of these membranous ATPases, H(+)-ATPase seemed to constitute only one tenth of the ATPase activity on rat liver lysosomes and to be the only ATPase that exposed its active site to the cytoplasmic side of the lysosomal membranes.

Adenosine Triphosphatases↗

PubMed1991

[Effect of halothane, fentanyl and ketamine on the threshold for the passage of venous air embolism through lungs in dogs].

Effect of halothane, fentanyl and ketamine on the passage of air injected bolus across the pulmonary circulation was studied in dogs using transesophageal M-mode echocardiography. Dogs in Group 1 (N = 5) were anesthetized with halothane and then halothane with fentanyl. At least 3 weeks later the dogs were anesthetized with fentanyl and then fentanyl with halothane. The same procedure was utilized in group 2 (N = 4) using halothane and ketamine. The doses of halothane, fentanyl and ketamine were 1% inspired concentration, 100 micrograms.kg-1 followed by 1 microgram.kg-1.min-1 iv, and 10 mg.kg-1 followed by 0.1 mg.kg-1.min-1 iv, respectively. The threshold for bolus air detection during halothane, fentanyl and ketamine alone were 0.05, 0.5 and 0.2 ml.kg-1, respectively. The threshold during fentanyl administration, but not during ketamine administration, was significantly higher than that during halothane. The addition of halothane to fentanyl or ketamine lowered the threshold to the same level as with halothane alone, and the addition of either fentanyl or ketamine to halothane made no difference. Although there was no difference in baseline shunt fraction resistance index [PVRI/(Qs/Qt)] during administration of each anesthetic, every air injection decreased shunt fraction resistance index during halothane without fentanyl or during halothane with or without ketamine, and increased it during fentanyl administration.

Animals↗

PubMed1990

[A case of emphysematous cystitis].

Emphysematous cystitis is a rare but interesting disease. A case is reported of cystitis emphysema with acute pyelonephritis and uncontrolled diabetes. The patient was a 54-year-old woman complaining of gross hematuria and fever. A submucosa emphysema in bladder was found by cystoscopy . Radiography showed the gas around the bladder. The patient was administered antibiotics, then symptoms was improved. We reviewed 12 cases of emphysematous cystitis reported in Japan and summarized the pathophysiologic features of this entity.

Acute Disease↗

PubMed1989

[A case of herniation of the bladder].

A 34-year-old man was admitted with pain on urination, pollakisuria and left inguinal hernia. He had undergone a surgery for the left inguinal hernia 3 times, about 30 years, 28 years and 14 years earlier. Physical examination revealed that there was an elastic soft mass in the left inguinal region. Cystoscopy and cystography showed the bladder herniation and left vesicoureteral reflux (Grade 1). Radical surgery for the hernia of bladder was not performed. The literature on the hernia of the bladder in Japan were collected and discussed.

Adult↗

PubMed1989

[Anesthetic management of elderly patients in open heart surgery].

In the National Cardiovascular Center, 46 patients whose ages were above 70 underwent open heart surgery from 1977 to 1986. Twenty of them received AC bypass and 5 had repair of the rupture of ventricular septum or left ventricular aneurysm. Among them 2 had also insertion of left ventricular assist device because of acute myocardial infarction (MI). Eighteen underwent mitral and/or aortic valve replacement. The other 3 were operated on because of atrial myxoma etc. Preoperatively, in ischemic heart disease group, due to resultant heart failure, one third of the patients were given catecholamines. In valvular heart disease group, angina pectoris and old MI were also common. Beside arrhythmias, respiratory complications, renal dysfunction and diabetes mellitus, neurological complications such as brain infarction were prominent in both groups. Hospital mortality was 15% in AC bypass group, 40% in acute MI group and 11.1% in VHD group. In 36 patients who left hospital, mean NYHA class improved after operation. The mortality rate and symptomatic improvement demonstrate that cardiac surgery can be performed with acceptable risk in elderly patients. Anesthesiologists should manage them carefully, considering the problems stated above.

Aged↗

PubMed1987