Search PubMed⌕ Search

Biomedical subjects

I Yoshiya

Publications and source records attributed to I Yoshiya.

At least 163 records · Page 9Linked to original sources

[Three cases with an extensive lesion in the dependent portion of the lungs diagnosed by chest CT-scan].

Three patients whose lung diseases are diagnosed with CT-scan are reported. A patient showed severe hypoxemia without any abnormal shadow on chest X-P. CT-scan revealed a diffuse and extensive lesion in the dependent portion. We performed his respiratory care in prone position. CT-scan of the second patient with aspiration pneumonia revealed that the lesion existed in the dependent portion. Cardiogenic pulmonary edema of the third patient was found to be distributed mainly in the dependent portion by CT-scan. We consider that CT-scan is useful when chest X-P gives little information.

Humans↗

Effects of carboxyhemoglobin on pulse oximetry in humans.

Carboxyhemoglobin (HbCO)-induced reading errors of the Biox 3700 (version J, Ohmeda) pulse oximeter were determined in 6 healthy volunteers rendered hypoxic (Sa(O)(2) from 65-100%) by breathing mixtures of air in nitrogen. The oximeter reading (Sp(O)(2)) before and after cigarette smoking was compared with oxyhemoglobin percentage (%HbO(2)). Mean HbCO levels were; 3.0 +/- 1.0 (SD) % before cigarette smoking and 5.2 +/- 1.7% after smoking, whereas mean methemoglobin was unchanged as 0.5 +/- 0.1%. The correlations of the Sp(O)(2) (y) with %HbO(2) (x) were; y = 1.01x - 0.30 (r = 0.990, n = 21, P < 0.001) when %HbCO was less than 2.5, and y = 1.01x + + 3.21 (r = 0.964, n = 33, P < 0.001) when %HbCO was above 5.0%. The reading error, (Sp(O)(2) - %HbO(2)), could be expressed as a function of %HbCO; 1.06 x %HbCO(2) - 2.49 (r = 0.669, n = 83, P < 0.05). Thus, the Sp(O)(2) is approximately the sum of %HbCO(2) and (%HbCO - 2.5), and overestimates %HbO(2) in the high levels of HbCO. The pulse oximeter should be used with caution in patients with the elevated level of %HbCO.

Journal Article↗

Synergistic interaction of alpha 1- and beta-adrenoceptor agonists on induction arrhythmias during halothane anesthesia in dogs.

The authors investigated the role of alpha 1- and beta-adrenoceptors on the induction of arrhythmias during halothane anesthesia in the dog. The arrhythmogenic doses (ADs) of various combinations of alpha 1- and beta-adrenoceptor agonists were determined in dogs (N = 105) during halothane anesthesia. Isoproterenol (ISP) and phenylephrine (PHE) administered separately failed to induce arrhythmias in doses up to 4 micrograms/kg and 200 micrograms/kg, respectively. The interaction between ISP and PHE in inducing arrhythmias showed typical hyperbolic isoboles. At a systolic pressure of 140 mmHg, the AD of ISP in the presence of PHE was significantly lower than that in the presence of angiotensin II (ANG II). At a systolic pressure of 150, 160, 170, or 180 mmHg, there was no significant difference between the AD of ISP in the presence of PHE and that in the presence of ANG II. Increasing heart rate by electrical pacing did not replace ISP in the arrhythmogenic interaction between ISP and PHE. The results indicate that both alpha 1- and beta-adrenoceptor agonists are important for producing arrhythmias during halothane anesthesia, and that these agonists synergistically interact on the heart by different mechanisms.

Adrenergic alpha-Agonists↗

Rapid determination of amphotericin B levels in serum by high-performance liquid chromatography without interference by bilirubin.

A high-performance liquid chromatographic method for the determination of amphotericin B concentrations in human serum without bilirubin interference was developed and compared with a microbiological assay. The high-performance liquid chromatographic assay utilized a reversed-phase trimethyl silica column, simple sample preparation, and visible detection. Reproducibility studies yielded coefficient-of-variation ranges from 1.02 to 2.11% for within-day precision and 2.88 to 4.32% for between-day precision. The correlation coefficient with the microbiological assay was 0.984 for amphotericin B.

Amphotericin B↗

Postoperative paraplegia associated with epidural narcotic administration.

Epidural injections of buprenorphine were given for postoperative pain relief to a patient with pulmonary carcinoma who underwent a right upper lobectomy. Paraplegia occurred postoperatively and the patient's neurological status deteriorated after each injection of epidural narcotic. Laminectomies on the third postoperative day revealed an expanded oxidized cellulose (Oxycel) pledget in the epidural space. Neurologic dysfunction after epidural narcotic administration was caused by the oxidized cellulose which had migrated into the epidural space following use for surgical haemostasis and subsequently expanded with the narcotic solution and blood.

Aged↗

Prostaglandin E1 in pulmonary hypertension of collagen disease.

A 47-yr-old woman with low cardiac output and dyspnea due to pulmonary hypertension associated with rheumatoid arthritis was treated with two vasodilators. Although nicardipine, a Ca-channel blocking agent, reduced the pulmonary artery pressure (PAP), it reduced simultaneously the arterial BP, resulting in fluid retention with a low urine output and persistent high CVP. In contrast, prostaglandin E1 (PGE1) reduced successfully both the PAP and CVP. Although the BP decreased, a satisfactory urine output was maintained. The cardiac output increased from 3 to 4.5 L/min. PGE1 may help reduce reversible pulmonary hypertension of collagen disease.

Alprostadil↗

Selective inhibition by dantrolene of caffeine-induced catecholamine release from perfused dog adrenals.

Effects of dantrolene sodium on catecholamine (CA) release from the perfused dog adrenal medulla was investigated in relation to it's therapeutic action on malignant hyperthermia (MH), in which CAs would play a significant pathophysiological role. Acetylcholine (ACh)-induced CA release was not affected, whereas caffeine-induced CA release was inhibited by dantrolene in a dose-dependent manner (84% inhibition at 10 microM). Dantrolene had no effect on the CA release induced by lasalocid or Na+ deprivation. On the other hand halothane inhibited ACh-induced CA release markedly, Na+ deprivation-induced CA release slightly, but not caffeine-induced CA release at all. The results indicate that dantrolene selectively inhibit caffeine-induced CA release, and that the therapeutic action of dantrolene on MH would be, at least in part, due to inhibition of abnormal release of Ca2+ in the adrenal medullary cells.

Adrenal Glands↗

Determination of cyclosporin A in whole blood by high-performance liquid chromatography using automated column switching.

A fully automated high-performance liquid chromatographic column-switching system is presented for the determination of cyclosporin A in whole blood. After blood proteins were precipitated with acetonitrile, the supernatant was automatically loaded on to a cyanopropyl column for initial separation, and then the fraction containing cyclosporin A was loaded on to a trimethylsilica column for final separation and quantitation. Cyclosporin A was detected by ultraviolet absorption at 205 nm. The minimum detectable concentration of cyclosporin A was 5 ng/ml in 100 microliter of blood. The coefficient of variation of the method was 1.755, 1.748 and 0.655% in whole blood when spiked at the 170, 425 and 850 ng/ml levels, respectively. One assay was completed in 15 min.

Autoanalysis↗