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Biomedical subjects

T Kuramoto

Publications and source records attributed to T Kuramoto.

At least 109 records · Page 6Linked to original sources
PubMed1990

Identification of short side chain bile acids in urine of patients with cerebrotendinous xanthomatosis.

Urine from patients with cerebrotendinous xanthomatosis (CTX) was found to contain a number of minor bile acids along with three major bile acids, 7-epicholic acid, norcholic acid, and cholic acid. The following minor bile acids were identified by combined gas-liquid chromatography-mass spectrometry: 7-ketobisnordeoxycholic acid; 12-ketobisnorchenodeoxycholic acid; 7-ketonordeoxycholic acid; 12-ketochenodeoxycholic acid; 7-ketodeoxycholic acid; 12-ketochendeoxycholic acid; bisnorcholic acid; allonorcholic acid; allocholic acid; 1 beta-hydroxybisnorcholic acid; 1 beta-hydroxynorcholic acid; 1 beta-hydroxycholic acid; 2 beta-hydroxybisnorcholic acid; 2 beta-hydroxy-norcholic acid; 2 beta-hydroxycholic acid. The presence of C22 and C23 bile acids in urine of the CTX patients suggests that bile alcohols having a hydroxyl group at C22 or C23 in the side chain may be further degraded to these bile acids.

Bile Acids and Salts↗
PubMed1990

[Severe lightning pain during spinal anesthesia].

A 74-yr-old man was scheduled for the biopsy of prostatic tumor under spinal anesthesia. Preoperative serologic test for syphilis was highly positive. Spinal anesthesia was performed in the sitting position, and 2 ml of hyperbaric Neo-percamine S (a mixture of 0.24% dibucaine and 0.12% T-caine) was administered uneventfully with the onset of warm sensation on the perineal region. Ten minutes later, however, he began to complain of severe lightning sensation on the feet. After giving pentazocine intravenously, the short cystoscopic procedure was completed. As a cause of severe pain, an erroneous anesthetic solution or direct neuronal injury had been excluded because of rapid and complete recovery after anesthesia. Two weeks later, he was scheduled for TUR-P. He again complained of severe lightning pain after the successful spinal anesthesia with the same anesthetic solution. Because the pain was not relieved by analgesics, he was then anesthetized with enflurane and N2O in oxygen, and there were no neurological complications after anesthesia. Several cases of severe pain during spinal anesthesia have been reported in patients with tabes dorsalis. Although the patient lacks clear symptoms of neurosyphilis, positive serologic examination for syphilis without any other possible causes suggests altered sensitivity of the spinal cord to anesthetic solutions.

Aged↗
PubMed1990

[Application of fuzzy algorithms for ventilatory control during clinical anesthesia].

A computer program, which calculates the required minute volume using fuzzy set rule incorporating the authors' clinical experiences, was developed to keep a stable PCO2 during anesthesia, and its clinical usefulness was examined on 30 consecutive patients. The program requires the value of end-tidal CO2 concentrations at present, and 5 minutes before, and arterial-end-tidal CO2 tension difference (aEDCO2), and generates the adjustable value of minute volume to maintain the constant PaCO2 (acceptable range; 37 to 33 mmHg). Twenty-three cases were successfully controlled after adopting the calculated minute volume, which closely coincided with our clinical experiences. Seven cases, on the other hand, did not show the anticipated PaCO2 change, because of incidental leakage of endotracheal cuff (2 cases), larger aEDCO2 than the expected value of 4 mmHg (4 cases), or mild pulmonary edema (1 case). It has become clear that in the steady anesthetized patients, the program based on the authors' clinical experiences, which was made possible with the concept of fuzzy set rule, can be used to control the PaCO2 within the strict range during variable anesthetic situations.

Adult↗
PubMed1989

Synthesis of 5 beta-cholestane-3 alpha,6 beta,7 alpha,25,26-pentol and identification of a novel bile alcohol, alpha-trichechol, present in the West Indian manatee bile.

In order to confirm the structure of alpha-trichechol, the major bile alcohol of the West Indian manatee, chemical synthesis of 5 beta-cholestane-3 alpha,6 beta,7 alpha,25,26-pentol was carried out. The chain of 3 alpha-hydroxy-5 beta-chol-6-en-24-oic acid was elongated by an Arndt-Eistert reaction to form 3 alpha-hydroxy-26,27-dinor-5 beta-cholest-6-en-25-oic acid. The unsaturated C25 bile acid was converted into 3 alpha,6 beta,7 alpha-trihydroxy-25-homo-5 beta-cholan-25-oic acid by 1,2-glycol formation of the delta 6-double bond. The acetylated derivative of the trihydroxy C25 bile acid was then converted into 3 alpha,6 beta,7 alpha,26-tetraacetoxy-27-nor-5 beta-cholestan-25-one by successive treatment with thionyl chloride, diazomethane, and acetic acid. A Grignard reaction of the 25-oxo compound with methylmagnesium iodide afforded the desired bile alcohol, 5 beta-cholestane-3 alpha,6 beta,7 alpha,25,26-pentol. By direct comparison with the synthetic pentahydroxy bile alcohol, the structure of the naturally occurring alpha-trichechol was determined to be 5 beta-cholestane-3 alpha,6 beta,7 alpha,25,26-pentol.

Animals↗
PubMed1989

Three cases of acute massive hydrothorax complicating continuous ambulatory peritoneal dialysis (CAPD).

Acute hydrothorax is a rare complication of continuous ambulatory peritoneal dialysis (CAPD). We experienced three such cases among patients who started CAPD in our institute between April 1984 and April 1989. One was resolved with pleurodesis using autologous blood. The other two patients were switched to hemodialysis permanently because pleurodesis with autologous blood, tetracycline or OK432 failed. Acute hydrothorax is one important possible complication in CAPD.

Adult↗
PubMed1989

Identification of bile alcohols in rat bile.

Bile alcohols in rat bile were analyzed by gas-liquid chromatography-mass spectrometry. Six bile alcohols were newly identified as minor constituents in addition to 5 beta-cholestane-3 alpha,7 alpha,12 alpha,26-tetrol, major bile alcohol of rat bile. The bile alcohols newly identified were 27-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25-pentol, 5 alpha-cholestane-3 alpha,7 alpha,12 alpha,26-tetrol, 5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,26-pentol, 5 alpha-cholestane-3 alpha,7 alpha,12 alpha,25,26-pentol, 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25,26-pentol, and 5 beta-cholestane-3 alpha,6 beta,7 beta,25,26-pentol. The biliary bile alcohols of the rat occurred mainly as the sulfuric acid esters and, in lesser amounts, as glucuronoconjugated and unconjugated forms. The amount of total bile alcohols was about 27.9 nmol in 1 ml of bile.

Animals↗
PubMed1989

[Effects of cimetidine on plasma concentration of catecholamine and baroreflex control of heart rate in anesthetized humans].

To clarify the mechanism of cardiovascular depression by cimetidine, we studied the effects of intravenous cimetidine on the plasma catecholamine concentration and baroreflex control of heart rate in man before and during enflurane-nitrous oxide anesthesia. Baroreflex control of heart rate was assessed by raising the arterial pressure by phenylephrine. Before anesthesia, 200 mg cimetidine decreased plasma epinephrine concentration (E) from 135 +/- 48 (s.e.) pg.ml-1 at baseline to 91 +/- 35 pg.ml-1 5 min after administration, but there were no significant changes in the norepinephrine concentration (NE), slope of pressor response, systolic blood pressure (SBP) or heart rate (HR). In anesthetized patients, baseline values of E, NE and slope were all significantly decreased as compared to those without anesthesia. However, cimetidine administered during anesthesia decreased both SBP and HR, by 19 +/- 5 mmHg and 9 +/- 6 beats.min-1, respectively, without further decrease of plasma catecholamine or slope by cimetidine than those at baseline. We conclude that inhibition by cimetidine of cardiovascular system during anesthesia is not due to further depression of baroreflex or plasma catecholamine concentration.

Anesthesia, Inhalation↗
PubMed1987

Intestinal absorption and metabolism of homoursodeoxycholic acid in rats.

Intestinal absorption, hepatic biotransformation and intestinal bacterial modification of the C25 homolog of ursodeoxycholic acid, homoursodeoxycholic acid, and its glycine conjugate, glycohomoursodeoxycholic acid, were studied in rats. Homoursodeoxycholic acid, like ursodeoxycholic acid, was efficiently absorbed from the intestine and rapidly excreted into the bile. Most (greater than 95%) of the absorbed homoursodeoxycholic acid was found to undergo beta-oxidation to form two C23 bile acids, norursodeoxycholic acid and nor-beta-muricholic acid during passage through the liver. Bacterial modification of homoursodeoxycholic acid was very similar to that of ursodeoxycholic acid. In the rat intestinal tract, glycohomoursodexycholic acid was deconjugated to form unconjugated homoursodeoxycholic acid which was then 7 beta-dehydroxylated to form homolithocholic acid.

Animals↗
PubMed1987

Identification of 5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25,26-hexol in human urine.

A new bile alcohol, 5 beta-cholestanehexol, was identified in the urine of healthy humans as the glucuronide. The bile alcohol glucuronide fraction was isolated by an ion exchange chromatography on piperidinohydroxypropyl Sephadex LH-20. After enzymatic hydrolysis, the bile alcohols were converted into trimethylsilyl ether derivatives and analyzed by a combination of gas-liquid chromatography and mass spectrometry. The major bile alcohol was 27-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25-pentol. As minor constituents the following C26 and C27 bile alcohols were identified: 27-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25,26-hexol, 5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25-pentol, 5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,26-pentol, 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25,26-pentol. In addition to these bile alcohols, a new bile alcohol was identified as a sixth component of the urinary bile alcohols. The structure was assigned as (24S)-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25,26-hexol by the direct comparison of mass spectral data and chromatographic properties with synthetic standard. The average daily excretion of the new bile alcohol was 28.6 micrograms and 3.0% of the total bile alcohols. The presence of 27-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25-pentol and 27-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25,26-hexol suggests that 26-hydroxylation of 5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25-pentol is most likely for the biosynthesis of this new bile alcohol.

Adult↗
PubMed1985

Effects of perfusion pressure on the bursting neurons in the intact or segmented cardiac ganglion of the lobster, Panulirus japonicus.

Impulse activity of the bursting neurones in the intact or segmented cardiac ganglion could be recorded in the isolated and freely beating hearts of lobsters. In the segmented ganglion, the four large cells (LCs), the medium cell (MC), and the four small cells (SCs) generated phasic, short tonic, and long tonic bursts of impulses with different rhythms, respectively. The periodic bursts of the LCs, the MC, and the SCs in the intact and the segmented ganglia were perturbed by a change of heart tonus which reflected a change of perfusion pressure in the heart. When correlation between period and duration of the perturbed bursts was plotted, the LCs, the MC, and the SCs in the segments were different from one another in distribution of the plots. Further, the correlation plots for the bursts of the MC in the intact ganglia were compared to those of the LCs, the MC, and the SCs in the segmented ganglia. The burst period and duration of the MC in the intact ganglion were altered markedly by a change of the burst period of the LCs and the burst duration of the SCs, as well as by change of heart tonus.

Action Potentials↗
PubMed1985

Intestinal absorption and metabolism of norcholic acid in rats.

Intestinal absorption and hepatic and intestinal bacterial biotransformations of norcholic acid, the C23 homologue of cholic acid, were studied in the rats. Norcholic acid, like cholic acid, was efficiently absorbed from the intestine and quickly secreted into the bile. Unlike the C24 bile acid, however, which is secreted by rat liver as its taurine conjugate, the C23 bile acid appeared in the bile predominantly as the unconjugated form. conjugated form. Bacterial modification of norcholic acid was similar to but less extensive than that of cholic acid. A considerable part of norcholic acid was left unchanged during its passage through the intestinal tract. A major bacterial metabolite of norcholic acid was the 7-dehydrogenation product, 7-ketonordeoxycholic acid, rather than the 7-dehydroxylation product, nordeoxycholic acid, though the reverse is true for cholic acid.

Animals↗
PubMed1985

Clinical value of biological activity of serum luteinizing hormone in patients with ovulatory failure.

Effects of LH-RH injection on the biological and immunological activities of LH were studied in patients with ovulatory failure. The LH-RH stimulation induced an abrupt increase in both biological and immunological activities of LH in both normal women and patients with ovulatory failure. The mean ratio of biological to immunological LH activities (B/I ratio) before LH-RH injection was 1.06 +/- 0.06 in the group of normal women, and was stable in each case for up to two hours after LH-RH injection. Patients with ovulatory failure could be divided into 2 subgroups on the basis of the B/I ratio of basal LH: one with a B/I ratio within the normal range (mean +/-2SD of B/I ratio in normal women) and one with a B/I ratio greater than the normal range. Patients with a normal B/I ratio had good responses to the clomiphene treatment, whereas those with a high B/I ratio showed poor responses to the same treatment. The basal levels of serum estradiol were significantly (p less than 0.05) lower in patients with a high B/I ratio than those with a normal B/I ratio. These results suggested that the determination of the B/I ratio would be a useful parameter in clinical care.

Adolescent↗
PubMed1985

Identification of bile alcohols in human bile.

Human gallbladder bile was examined for bile alcohols. Following isolation and hydrolysis, the bile alcohols were analyzed by capillary gas-liquid chromatography-mass spectrometry. The following bile alcohols were identified with certainty by direct comparison with reference standards: 5 beta-cholane-3 alpha,-7 alpha,23,24-tetrol; 5 beta-cholane-3 alpha,7 alpha,12 alpha,24-tetrol; 24-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol; 27-nor-5 beta-cholest-25-ene-3 alpha,7 alpha,-12 alpha,24-tetrol; 3 alpha,7 alpha,12 alpha-trihydroxy-27-nor-5 beta-cholestan-24-one; 27-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25-pentol; 27-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25,26-hexol; 5 beta-cholestane-3 alpha,7 alpha,24-triol; 5 beta-cholestane-3 alpha,7 alpha,25-triol; 5 beta-cholestane-3 alpha,7 alpha,26-triol; 5 alpha-cholestane-3 alpha,7 alpha,12 alpha,24-tetrol; 5 beta-cholestane-3 alpha,7 alpha,12 alpha,24-tetrol; 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol; 5 beta-cholestane-3 alpha,7 alpha,12 alpha,26-tetrol; (24R)- and (24S)-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25-pentols; 5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,26-pentol; 5 beta-cholestane-3 alpha,7 alpha,12 alpha,-25,26-pentol; 5 beta-cholestane-3 alpha,7 alpha,12 alpha,26,27-pentol; 26-methoxy-5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol. There also existed two norcholestanetetrols and three cholestanetetrols with two hydroxyl substituents on the nucleus and two in the side chain. The human biliary bile alcohols occurred mainly as sulfate esters and in lesser amounts as glucuronoconjugated and unconjugated forms. The amount of total bile alcohols was about 0.9 mg (0.7-1.2 mg) in 1 g of bile solid, or 0.16 mumol (0.07-0.24 mumol) in 1 ml of gallbladder bile.

Bile↗
PubMed1984

Synthesis, intestinal absorption and metabolism of sarcosine conjugated ursodeoxycholic acid.

Sarcosine conjugated ursodeoxycholic acid (SUDC) was synthesized and its intestinal absorption and metabolism were studied in rat and hamster. Intestinal absorption study using bile fistula rat shows that more than 90% of SUDC administered intraduodenally was excreted in the bile within 24 hr. No change of the administered bile acid was seen during the absorption from the intestine, the passage of the liver, and the excretion into the bile. When [24-14C]SUDC and [11,12-3H2]-ursodeoxycholic acid were administered orally to a hamster, more than 95% of both the administered 14C and 3H were recovered from the feces within 6 days. Most (77%) of the fecal 14C-labeled compound was SUDC, whereas 95% of the fecal 3H-labeled compound was unconjugated lithocholic acid. These results indicate that SUDC, unlike taurine or glycine conjugated bile acid, resists bacterial deconjugation and 7-dehydroxylation.

Animals↗