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Biomedical subjects

Y Fukui

Publications and source records attributed to Y Fukui.

At least 487 records · Page 27Linked to original sources
PubMed1982

Digital and sampled-data control of arterial blood pressure during halothane anesthesia.

A control system that maintains mean arterial pressure (MAP) at a desired level by automatically controlling halothane input has been developed. The control system is a discrete, digital type and is implemented with a small desk-top programmable calculator. Essentially, if MAP decreases, the inspired concentration of halothane will decrease; if MAP increases, the system will compensate by increasing inspired halothane concentration. The control system was tested in two ways: with a hybrid computer model of uptake and distribution of halothane and with dog experiments. The results indicate that (a) the model can be used to predict the response of the animal-anesthesia machine control system, and (b) the proposed algorithm is successful in controlling one anesthetic agent with one physiologic variable.

Anesthesiology↗
PubMed1981

Glia maturation factor in bovine brain: partial purification and physicochemical characterization.

Glia maturation factor (GMF) is partially purified from bovine brains by the following procedure: extraction at physiologic pH, dialysis and freeze-drying of the extract, ethanol washing of the dried powder and re-extraction of the ethanol-washed residue with Tris-buffered saline, ion-exchange chromatography with DEAE Sephadex and molecular sieving with Bio-gel P-200. The partially purified protein has an apparent molecular weight of 23,000 and an isoelectric point of 4.75, and retains both morphological transforming and mitogenic activities when tested on glioblasts. Both activities are susceptible to protease digestion and heat inactivation. The procedure results in a 400-fold purification of the morphological activity and a 1400-fold purification of the mitogenic activity. Both activities are detectable when GMF is used in nanogram quantities. The possibility that both functions are expressions of the same factor and the possible role of GMF in the differential or sequential stimulation of cell growth and maturation are discussed.

Animals↗
PubMed1981

Relationship between doses of prostaglandin F2alpha and stages of the breeding season for synchronization of estrus and ovulation in ewes.

Two experiments were conducted to compare estrous response to three doses (8, 16 and 24 mg) of prostaglandin F2alpha (PGF2alpha) administered by intramuscular injection to ewes between day 6 and 12 of the estrous cycle (Experiment I) and to ewes on unknown days of the estrous cycle during four different stages of the breeding season (Experiment II). In experiment I, a total of 41 ewes were treated with PGF2alpha. The injection of 24 mg PGF2alpha resulted in a higher proportion of ewes exhibiting estrus (13/14, 92.9%) within 5 days after treatment as compared to the other two doses (2/12 and 10/15, for 8 and 16 mg PGF2alpha, respectively). However, there was no significant difference for the proportion between 16 mg and 24 mg PGF2alpha. In experiment II, PGF2alpha was given to ewes on the 3rd of February (early breeding season), the 28th of February (mid-early breeding season), the 10th of April (mid breeding season) and the 27th of May (late breeding season). These was a significant difference for the proportion of ewes exhibiting estrus between the early breeding season and the other three seasons (P<0.05) but not for ewes ovulating. Throughout the breeding season, 16 mg PGF2alpha appeared to be slightly better than the other two doses (8 and 24 mg) although there was no overall difference in the estrous responses to treatment among the three doses. However, a significant difference in the proportion of ewes ovulating was found among the three doses of PGF2alpha (P<0.05). Especially, 16 mg PGF2alpha was significantly superior to 8 mg (P<0.01) and 24 mg (P<0.05). It was considered that there was a complicated relationship between the doses of PGF2alpha and the stages of the breeding season for induction of estrus and ovulation in the ewe.

Journal Article↗
PubMed1981

Dimethyl sulfoxide inhibits capping of surface receptors.

The microfilaments of cellular slime mold cells are known to be dislocated from their attachment to the plasma membrane by 10% dimethyl sulfoxide (DMSO). We report here that 10% DMSO inhibited capping of lentil lectin receptors on the surface of vegetative cells of the cellular slime mold, Dictyostelium mucoroides. When the DMSO was washed from the cells, capping took place. Capping of surface immunoglobulin of mouse lymphocytes was also reversibly inhibited by 10% DMSO.

Animals↗
PubMed1981

Interactions among ventilation, the circulation, and the uptake and distribution of halothane--use of a hybrid computer multiple model: I. The basic model.

The authors describe an 18-compartment hybrid computer multiple model of the uptake and distribution of halothane. This model uses 88 equations and 124 parameter settings. Three submodels are incorporated into the basic model: 1) The mass transport of halothane is simulated on the digital portion of the hybrid computer. 2) A breath-by-breath pulmonary model with two compartments describes air pressure-flow relations in the airway system. 3) A beat-to-beat cardiovascular model with 15 compartments describes in detail blood pressure-flow relations. In addition, a baroreceptor-heart rate loop is included: an increase in arterial pressure causes a decrease in heart rate. The slope of the baroreceptor response is progressively decreased by halothane until at 2 per cent there is no response. The model of halothane uptake and distribution is separate from the blood and air pressure-flow models, but is, in effect, driven by them. Myocardial "contractility" (stroke volume) and certain regional vascular resistances can be affected by the concentration of halothane in one or any proportion of any combination of three compartments: arterial blood (arteriolar concentrations), cerebral gray matter, or myocardial. In turn, these factors significantly affect the uptake and distribution of halothane. The responses to three steady-state concentration, as well as to a step change in concentration from 0 to 2 per cent, were examined. Twenty-four outputs were recorded, including halothane concentrations in ten compartments; myocardial "contractility"; left and right ventricular and right atrial pressures; cardiac output; stroke volume, R-R interval; and blood flows in six regions. Two variables--alveolar concentration of halothane and arterial blood pressure--were recorded during a step change of 0 to 5 per cent. The model describes the appropriate steady-state and dynamic cardiovascular responses to halothane. It also demonstrates the complex interrelationships among caridac output, regional blood flow distribution, and the uptake and distribution of halothane. During step change in halothane concentration, most of the responses occur early, a phenomenon also seen in man and goats. Thus, the model is useful not only for representing organ and tissue halothane concentrations, but also for gaining new insights into cardiovascular alterations produced by rapidly changing concentrations of halothane and into the complex interactions between the circulation and the uptake and distribution of halothane.

Anesthesia, Inhalation↗
PubMed1981

Interactions among ventilation, the circulation, and the uptake and distribution of halothane--use of a hybrid computer multiple model: II. Spontaneous vs. controlled ventilation, and the effects of CO2.

The authors have described a basic hybrid computer multiple model of the circulation, ventilation, and uptake and distribution of halothane in a companion paper. A multiple model consists of two or more submodels, each of which is complete in itself and could operate independently. In a multiple model, however, each submodel interacts with the others. The present paper describes the addition of a CO2-control loop (submodel), through which the partial pressure of CO2 modulates ventilation, as well a myocardial "contractility," arterial pressure, cardiac output, and regional vascular resistances. The concentration of halothane modifies these CO2-induced modulations. The CO2- and halothane-induced changes in ventilation and circulation in turn modify the uptake and distribution of halothane. Thus, a complex set of interrelationships among the submodels and compartments exists.

Anesthesia, Inhalation↗
PubMed1981

Recovery of CNV area after nonresponse condition: inverted-U relation with arousal.

The effect of motor-response recovery after a nonresponse condition on the CNV was investigated in relation to the MPI in 53 healthy adults. The control CNV area before the nonresponse condition had an inverted-U relation to the extraversion score. At the recovery condition the inverted-U relation between the CNV area and the extraversion score shifted toward the lower extraversion score in those subjects who showed a shortened reaction time: i.e., the introverts, particularly the dysthymiacs, responded with the larger CNV area at the recovery condition than at the control condition. These results suggest that the dysthymiacs who possibly have obsession and depression are at a high arousal level and compel attention to a repetitive event as habituating.

Adult↗
PubMed1981

Incomplete transformation of rat cells by a deletion mutant of adenovirus type 5.

Rat 3Y1 cells were infected with adenovirus type 5 (Ad5) wild type, dl312 (deletion of 902 base pairs between 1.5-4.5 map units), and dl313 (deletion of 2,350 base pairs between 3.5-10.5 map units). After cultivation for 4 weeks, transformed foci appeared in wild type- and dl313-infected cells. No focus was observed in dl312- and mock-infected cells. Foci induced by dl313 were less dense than those induced by wild type. Cell lines (313Y cells) established from dl313-induced foci contained the E1 gene of the dl313 genome (E1a only). Cell lines (5WY cells) established from Ad5 wild type-induced foci contained the E1 gene of wild type (E1a and b). The difference between the transcriptional patterns of the E1 gene in 313Y cells and that in 5WY cells was the same as the difference in dl313- and wild type-infected cells. Colonies were formed in soft agar culture inoculated with 5WY cells, but no colony was formed after inoculation of 313Y cells. The transformed phenotype of 313Y cells was incomplete compared with that in 5WY cells. In nongrowing 3Y1 cells, dl313 and Ad5 wild type induced cellular DNA synthesis but dl312 did not. The above results suggest that the E1a gene is functioning in dl313-infected but not in dl312-infected cells and that such functions as induction of cellular DNA synthesis and transformation of cells are dependent on expression of the Ad5 E1a gene.

Adenoviruses, Human↗
PubMed1981

Cross-sectional echocardiographic study on the mitral valve prolapse associated with secundum atrial septal defect: pre- and post-operative comparison.

Cross-sectional echocardiography was performed on 77 patients with secundum atrial septal defect (ASD). Mitral valve prolapse (MVP) was recognized in 41 out of the 77 (53.2%); anterior MVP was found in 36 patients, three cases revealed posterior MVP, and two were diagnosed as having both anterior and posterior MVP. Pre- and post-operative study was carried out on 53 cases; anterior MVP decreased in incidence from 28 patients to 17 following closure of ASD, whereas posterior MVP remained unchanged, as did both anterior and posterior MVP. The left ventricular distortion ratio (LVDR) was measured in the short axis view in 45 cases. After the repair of ASD, the LVDR decreased both in end-systole and end-diastole (p less than 0.01), that is, the left ventricle became more circular in configuration. Pre- and post-operatively, MVP patients revealed a significantly greater LVDR than those without it in end-systole, and post-operatively in end-diastole as well (p less than 0.01). Prior to operation, the short axis area of the left ventricle (LVSAA) was statistically larger in patients with MVP than without it in end-diastole (p less than 0.05). However, there existed no relationship between the presence of MVP and the pulmonic to systemic flow ratio, right ventricular dimension index, right ventricular systolic pressure and size of ASD at the time of operation.

Adolescent↗
PubMed1981

A lithium and carbamazepine combination in the treatment of bipolar disorder--a preliminary report.

A lithium and carbamazepine combination was reported in five patients with bipolar disorder (DSM-III), who had not received benefits from conventional treatments. Patients 1, 2 and 4 showed favorable antimanic responses to carbamazepine used in combination with lithium carbonate. Patient 3 did not respond well to either lithium or carbamazepine alone, but improved dramatically on the simultaneous administration of the two drugs. The prophylactic benefit was observed in two patients. These clinical results suggest that a lithium and carbamazepine combination may be more efficacious in the treatment of acute manic episode and the prevention of affective recurrences than each drug alone.

Adult↗
PubMed1980

A schizophrenic subgroup: type A5.

This report concerns a group of schizophrenics whose visual evoked potential reduced in amplitude most markedly in A5 (averaged potential evoked by 1 Hz flashes which started 5 min after the addition test for 15 min). These patients in general had poor productive symptoms and progressed very slowly. Most of them were simple schizophrenics.

Adult↗
PubMed1980

Dynamics of nuclear actin bundle induction by dimethyl sulfoxide and factors affecting its development.

We have reported in a previous paper that dimethyl sulfoxide (DMSO) induces the formation of huge bundles of actin filaments in the nuclei of Dictyostelium mucoroides. The present study was performed to provide electron microscope data on the induction of nuclear actin bundles, illustrating both their formation and their reversion, as well as on the effects of various factors on the induction. The large nuclear bundles of actin appeared after 20--30 min of treatment with 10% DMSO. A DMSO concentration of 5 or 10% was optimal for the induction of the bundles. The nuclear actin bundle reverted to the original morphology within 5 min after removing DMSO. Induction of nuclear actin bundles was inhibited by Mg++ and low temperatures, but not by Na+, K+, Ca++, ATP, 3'5'-cyclic adenosine monophosphate (cAMP), phosphate buffer, or cytochalasin B. Neither NaN3 nor cycloheximide totally inhibited the induction of the bundles.

Actins↗
PubMed1980

Formation of multinuclear cells induced by dimethyl sulfoxide: inhibition of cytokinesis and occurrence of novel nuclear division in Dictyostelium cells.

Our previous studies showed that 10 percent dimethyl sulfoxide (DMSO) induces the formation of actin microfilament bundles in the cell nucleus together with the dislocation of cortical microfilaments from the plasma membrane. The present study investigated the effects of DMSO on diverse activities mediated by cellular microfilaments as the second step toward assessing potential differences between nuclear and cytoplasmic actins of dictyostelium mucoroides. DMSO was found to reversibly inhibit cell-to- glass as well as cell-to-cell adhesion, cell locomotion, and cell multiplication, whereas cytoplasmic streaming and phagocytosis were not obviously inhibited. Also, 5 percent DMSO inhibited cytokinesis but did not totally inhibit cell growth thus leading to the development of giant cells more than 10 times larger than normal cells. Transmission electron microscopy using serial thin sections showed the occurrence of multinucleation in the DMSO- induced giant cells. After the removal of DMSO, the giant multinuclear cells underwent multiple cytoplasmic cleavage producing normal-sized mononuclear cells. The nuclear division in the DMSO-induced giant cells was unique in that no spindle microtubules were formed, and vesicles appeared inside the nucleus forming a transverse partition of the nuclear envelope. The presence of actin filaments in those nuclei was demonstrated by a binding study with skeletal muscle myosin subfragment-1, and their possible involvement in this mode of nuclear division is discussed.

Actins↗