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Biomedical subjects

N Nishimura

Publications and source records attributed to N Nishimura.

At least 235 records · Page 13Linked to original sources
PubMed1985

Oxygen consumption and carbon dioxide production following open heart surgery.

The VO2, VCO2 and RQ were measured in 24 patients after open heart surgery using a CO2 analyzer and O2 Consumption Calculator (Siemen Elma, Sweden). With prolonged ventilatory care, shivering was noticed in only one patient and VO2, VCO2 and RQ were rather stable and constant in patients in the Intensive Care Unit (ICU). With dopamine infusion the 3-5 kg body wt/min cardiovascular status was stable and the oxygen extraction ratio was a mean of 0.264. From those data we suggest that ventilatory support would be desirable for about 2 days for those patients in the post-operative period.

Adult↗
PubMed1985

The effects of volume loading during epidural analgesia.

We have determined the effects of volume loading on the cardiovascular changes during epidural analgesia in 37 patients, who underwent various kinds of surgery. The patients were placed in 4 groups, depending upon the level of analgesia and utilization of volume loading with colloidal solutions. If the analgesia extended above Th4 we grouped them as "high epidural" and lower than Th5 level they were grouped as "low epidural". The cardiac output was measured through a Swan-Ganz catheter with thermo-dilution methods and cardiovascular variables were calculated by standard formulas. Under epidural block the most significant changes were a fall in blood pressure with decrease in cardiac output which were more pronounced during high epidural analgesia. Volume loading during the induction period with colloidal solutions would prevent the marked fall of blood pressure in half of cases studied, but in the other half the infusion was not effective for the prevention of fall in blood pressure. On every occasion over-loading effects on the right side of the heart were observed with the infusion of colloidal solutions. Also, a marked fall in systemic vascular resistance was observed with the infusion. In consequence the volume loading did not prevent the fall in arterial pressure. To manage the latter which was observed during epidural block, some sympathomimetic agents would be necessary with the volume loading. This approach would be much more important in patients with dehydration and high level of epidural analgesia.

Adult↗
PubMed1985

Subcellular localization of hypothalamic luteinizing hormone.

Ultracentrifugation and sucrose gradient separation techniques have been applied to study of the subcellular distribution of hypothalamic luteinizing hormone (LH). Subcellular particle-bound LH accounted for 42% of the total LH while cytoplasm contained 58% of the total immunoassayable LH in these extracts. 70% of particle-bound LH was present in the P2 fraction and most of the particle-associated LH was found in subfractions of P2 rich in synaptosomes but poor in myelin and mitochondria. While actual amounts of LH in the P3 and P4, the microsomal fractions, were relatively small, the concentration of LH, expressed as nanograms per milligram of protein was quite high. Both content and concentration of LH in the nuclear pellet, P1, were substantially lower. These findings provide further framework for speculation on the role of brain-based LH.

Animals↗
PubMed1985

Suppression of delayed-type hypersensitivity mediated by macrophage-like cells in mice with experimental liver injury.

The intensity of picryl chloride-induced delayed-type hypersensitivity (PCl-DTH) was significantly lowered in mice with experimental liver injury induced by the injection of carbon tetrachloride (CCl4) or 1-naphthylisothiocyanate (ANIT). Adherent spleen cells prepared from mice with liver injury suppressed the PCl-DTH in normal syngeneic mice by adoptive transfer at the time of immunization with picryl chloride (PCl). Cianidanol, administered orally to recipient mice immediately after the transfer of adherent spleen cells, caused total prevention of the PCl-DTH from suppression by the transferred adherent spleen cells. In in vitro studies, the adherent spleen cells from both CCl4-treated and ANIT-treated mice produced higher amounts of prostaglandin E2 (PGE2) than those from normal mice. The addition of cianidanol at the beginning of incubation caused an inhibition of PGE2 production of the adherent spleen cells. Furthermore, the spleen cell suspensions from CCl4-treated mice gave a marked increase in generation of superoxide anions (O2-), also inhibited by the addition of cianidanol. Gathered results support the adherent spleen cell as being the cell causing the suppression of DTH in mice with experimental liver injury; the important role of PGE2 and O2- in the suppression of DTH mediated by the adherent spleen cells was demonstrated. Cianidanol eliminated the suppression of DTH, owing principally to the inhibitory effect on the production of PGE2 and O2- from the adherent spleen cells.

1-Naphthylisothiocyanate↗
PubMed1985

The effects of pantethine on lipid and lipoprotein abnormalities in survivors of cerebral infarction.

A daily 1000 mg of pantethine was orally administered to 12 male survivors of cerebral infarction for 3 months. Before and after the medication, plasma lipoproteins were ultracentrifugally separated. Plasma concentrations of total cholesterol, triglyceride, phospholipid, and VLDL- and LDL-cholesterol tended to decrease. On the contrary, HDL-cholesterol concentration and HDL:LDL-cholesterol ratio significantly increased. HDL2-cholesterol concentration significantly increased, whereas HDL3-cholesterol concentration remained unchanged, resulting in a significant elevation of HDL2:HDL3-cholesterol ratio. In HDL2 the percentage content of cholesterol and triglyceride decreased, while that of phospholipid increased. However, no significant changes were found in the chemical composition of HDL3. The plasma concentrations of apo A-I and, to a lesser extent, A-II increased, with a slight increase in A-I:A-II ratio but A-I:A-II ratio in either HDL2 or HDL3 remained unchanged.

Apolipoprotein A-I↗
PubMed1984

Cardiovascular changes in the terminal stage of disease.

In 11 patients with brain death, we measured cardiovascular parameters until cardiac arrest. After withdrawal of vasopressors, we observed marked falls in the cardiac output, systemic vascular resistance, heart rate and arterial pressure. In consequence, there was a marked decrease in oxygen delivery and the fall in arterial pressure established a vicious circle and circulatory death ensued. Most pronounced changes were left heart dysfunction and a fall in systemic vascular resistance. On the other hand, depression of the right side of the heart was half of that of left side, and the pulmonary circulation and volume status were well maintained until death. At the same time we found in these patients that body temperature and organ function except that of the brain were well maintained in brain dead patients. For resuscitation of apparently dead patients one must maintain not only cardiac functions but also systemic vascular functions.

Adult↗
PubMed1984

Circulatory support with sympathetic amines in brain death.

In 12 cases of brain death, the cardiovascular effects and changes of transcutaneous PO2 (PtcO2) during infusion of various sympathomimetic amines were determined. The larger amounts of vasopressors were necessary to maintain the blood pressure at more than 100 mmHg. With norepinephrine and dopamine, marked increase in blood pressure, cardiac output, systemic vascular resistance and also PtcO2 were observed. On the other hand, dobutamine was not an effective pressor agent in those situations. Even with more than 10 times the routinely used concentration of dobutamine, difficulties were encountered in keeping the blood pressure above 100 mmHg in many cases studied. With the infusion of dobutamine, a marked increase in cardiac output and heart rate were observed with a decrease in systemic vascular resistance and a fall in PtcO2 values in many occasions. In brain death, norepinephrine and dopamine will be recommended as the pressor agents in clinical practice. The changes of PtcO2 closely followed the changes of arterial blood pressure and did not parallel the changes of cardiac output or of heart rate.

Adult↗
PubMed1984

Metaraminol and dobutamine for the treatment of hypotension associated with epidural block.

In 14 patients undergoing major abdominal surgery, epidural analgesia was performed and cardiovascular changes were examined by insertion of Swan-Ganz catheters. To counteract the hypotensive episodes associated with epidural block, Dobutamine (1-3 micrograms/kg body wt min-1) and Metaraminol (0.5-1.5 micrograms/kg body wt min-1) in various doses were infused and the effects of these vasoactive agents were examined. Epidural analgesia decreased arterial pressure, pulmonary arterial pressure, pulmonary capillary wedge pressure and central venous pressure associated with marked decrease in cardiac index, stroke volume index, left ventricular and right ventricular stroke work without changes in systematic vascular resistance, pulmonary vascular resistance or heart rate. The infusion of Metaraminol caused a marked increase in arterial pressure, pulmonary arterial pressure, wedge pressure and central venous pressure. Calculated variables of stroke volume, systemic vascular resistance, left and right stroke work and cardiac work increased significantly. The infusion of Dobutamine caused a marked increase in arterial and pulmonary arterial pressure, wedge pressure, central venous pressure and cardiac index associated with those calculated changes of left and right stroke work and cardiac work, which were increased markedly. On the other hand, heart rate, stroke volume and pulmonary vascular resistance did not show any remarkable changes. Our study indicates that the fall in arterial blood pressure associated with epidural block may be due to marked decrease in cardiac output, and the infusion of Dobutamine is one of the desirable methods to counteract the hypotensive episode.

Adult↗
PubMed1984

Oxygen conformers in critically ill patients.

In 104 patients with various pathological conditions, the correlation between oxygen consumption and oxygen delivery was analysed by the least square method. As reported by Peirce in 1977, we also found oxygen conformers among critically ill patients, but a tendency to oxygen regulator was never found in our patients.

Adolescent↗
PubMed1984

Changes of hemodynamics and O2 transport associated with the perfluorochemical blood substitute, Fluosol-DA.

Hemodynamic, arterial O2 tension (PaO2) and transcutaneous O2 tension (PtcO2) changes associated with the infusion of 500 ml of Fluosol-DA were evaluated in 14 decerebrated patients. Flow-directed pulmonary artery catheters and the Clark-type oxygen electrode manufactured by Hoffmann-La Roche were utilized. The marked improvement of cardiovascular variables along with marked increases in PaO2 and PtcO2 may indicate a marked increase in skin circulation by the infusion of Fluosol. One patient exhibited a hypotensive episode during the infusion, which lasted only a short time, disappeared spontaneously, and did not prohibit the further infusion of Fluosol. We still consider that Fluosol will be clinically useful for increasing oxygen capacity and improving overall hemodynamic status as well as individual organ circulation.

Adult↗
PubMed1984

Aspartase-hyperproducing mutants of Escherichia coli B.

When a wild-type strain of Escherichia coli B was cultured on a medium containing L-aspartic acid as the sole carbon source (Asp-C medium), aspartase formation was higher than that observed in minimal medium. Addition of glucose to Asp-C medium decreased aspartase formation. When also cultured in a medium containing L-aspartic acid as the sole nitrogen source (Asp-N medium), E. coli B showed a low level of aspartase formation and an elongated doubling time. To obtain aspartase-hyperproducing strains, we enriched cells growing faster than cells of the wild-type strain in Asp-N medium by continuous cultivation of mutagenized cells. After plate selection, the doubling times of these mutants were measured. Thereafter, fast-growing mutants were tested for aspartase formation. One of these mutants, strain EAPc7, had a higher level of aspartase formation than did the wild-type strain in medium containing L-aspartic acid as the carbon source, however; addition of glucose to this medium decreased aspartase formation. The other mutant, strain EAPc244, had a higher level of aspartase activity than did the wild-type strain in both media. Therefore, aspartase formation in mutant EAPc244 was released from catabolite repression. In strain EAPc244 the other catabolite-repressible enzymes, beta-galactosidase, tryptophanase, and the three tricarboxylic acid cycle enzymes, were also released from catabolite repression. Both mutants had sevenfold the aspartase formation of the wild-type strain in a medium which contained fumaric acid as the main carbon source and which has been used for industrial production of E. coli B aspartase. However, strain EAPc244 had 2.5-fold the fumarase activity of strain EAPc7.(ABSTRACT TRUNCATED AT 250 WORDS)

Ammonia-Lyases↗