Search PubMed⌕ Search

Biomedical subjects

N Fukushima

Publications and source records attributed to N Fukushima.

At least 127 records · Page 7Linked to original sources
PubMed1997

Biocompatibility of heparin-coated circuits in pediatric cardiopulmonary bypass.

In this study, we evaluated the biocompatibility of heparin-coated circuits in pediatric cardiopulmonary bypass (CPB). Eight patients were divided into 2 groups: the control group (Group C) and heparin-coated group (Group H). In Group H, CPB circuits, including the arterial pump, oxygenator, and cannulas were heparin-coated. Before, during, and after CPB, blood samples were obtained to assess the platelet counts (Plat), alpha 2-plasmin plasminogen inhibitor complex (PIC), thrombin-antithrombin III complex (TAT), C3 activation products (C3a), interleukin (IL)-6, IL-8, and polymorphonuclear neutrophil leukocyte (PMN) elastase. There was no significant difference in Plat, PIC, or TAT between groups. Group H showed significantly low levels of C3a (during and after CPB), PMN elastase (during CPB), and IL-6 (after CPB). These data demonstrated that in pediatric CPB, heparin-coated CPB circuits reduced the activation of complements and the production of PMN elastase and IL-6, suggesting the superior biocompatibility of the heparin-coated circuits.

Anticoagulants↗
PubMed1997

Is there a safe limit to coronary sinus pressure during retrograde cardioplegia?

Although retrograde cardioplegia (RC) delivered via the coronary sinus (CS) is now used routinely, the pressure at which RC can be safely delivered is thought to be 50 to 60 mm Hg. Such practice is based on experiments performed on working, beating hearts with CS ligation and arterial inflow into both the coronary arteries and veins (Beck procedure). However, no data exist on arrested, vented hearts, as occurs clinically during RC. We studied the acute effect of 10 cc/kg of blood RC delivered into the CSs of 16 adult vented pig hearts, which were randomly assigned to four groups of four hearts each according to the CS pressure maintained during perfusion: 40, 80, 100, and 120 mm Hg. After RC, hearts were excised, cut in bread-loaf sections, examined grossly, and then fixed and stained. Sections of right ventricle, septum, and left ventricle were then examined by two blinded cardiac pathologists and two blinded surgeons and scored for the presence of extravascular hemorrhage. None of the 16 hearts tested showed any evidence of gross or microscopic hemorrhage; all hearts showed normal myocardial preservations and structure, including all hearts at 100 and 120 mm Hg CS perfusion pressure. We conclude that CS pressures up to 120 mm Hg cause no extravasation of blood into the myocardium in the vented, arrested heart. These results contradict studies on the working, beating heart, and suggest that high pressures in the CS are well tolerated during RC.

Animals↗
PubMed1996

Inositol 1,4,5-trisphosphate-gated calcium transport through plasma membranes in nerve terminals.

We developed new biochemical approaches to demonstrate the presence of inositol 1,4,5-triphosphate (InsP3)-gated calcium channels in presynaptic plasma membranes (SPM) and their involvement in the presynaptic receptor-mediated Ca2+ influx into nerve terminals. In perfusion experiments using SPM vesicles preloaded with 45Ca2+, InsP3 elicited the release of 45CA2+ into perfusates in a saturable manner. The InsP3- evoked 45Ca2+ release from resealed SPM vesicles was more potent than that from resealed vesicles using any other subcellular fractions. Here we also report the involvement of InsP3-gated mechanisms in the presynaptic receptor-mediated Ca2+ influx into synaptosomes (nerve terminals) by use of such resealed vesicles reconstituted with purified Gi1.

Adenosine Triphosphate↗
PubMed1996

Lack of association between dopamine D2 receptor gene Cys311 variant and schizophrenia.

Itokawa et al. [1993] reported identifying one missense nucleotide mutation from C to G resulting in a substitution of serine with cysteine at codon 311 in the third intracellular loop of the dopamine D2 receptor in schizophrenics. Arinami et al. [1994] reported finding a positive association between the Cys311 variant and schizophrenia. In response to the report by Arinami et al. [1994] we examined 106 unrelated Japanese schizophrenics and 106 normal controls to determine if there is any association of the Cys311 variant with schizophrenia. However, we found no statistically significant differences in allelic frequencies of Cys311 between schizophrenia and normal controls. The present results as well as those of all previous studies except for that of Arinami et al. [1994] indicated that an association between the dopamine D2 receptor gene and schizophrenia is unlikely to exist.

Adolescent↗
PubMed1996

Late true aneurysm after bypass grafting for long aortic coarctation.

Two adolescent patients who underwent a repair of long aortic coarctation using bypass grafting with subsequent late true aneurysm formation are reported. To our knowledge, only 1 case of late true aneurysm formation after bypass grafting has been reported in the English-language literature.

Adolescent↗
PubMed1996

A subtype of kappa-opioid receptor mediates inhibition of high-affinity GTPase inherent in Gi1 in guinea pig cerebellar membranes.

The kappa-opioid receptor agonists including U-50,488H and dynorphin A (1-17) in ranges of 0.1-100 nM inhibited the hydrolysis of GTP to GDP (P(i) release) inherent in GTP-binding proteins (G proteins) in guinea pig cerebellar membranes. U-50,488H inhibited only high-affinity GTPase activity, not low-affinity activity. The action of this agonist was found to be biphasic, and there was no inhibition at concentrations > 1 microM. The inhibition was abolished by pretreatment with preactivated pertussis toxin (PTX) at concentrations > 1 micrograms/ml but not with preactivated cholera toxin (30 micrograms/ml). Similar blockade of kappa-receptor-mediated inhibition was also observed when membranes were pretreated with a low concentration (8 microM) of N-ethylmaleimide (NEM) at low temperature (4 degrees C), which alkylates the cysteine residue to be ADP-ribosylated by PTX; but this treatment caused no significant change in kappa-agonist binding. When purified Gi1, but not G(o), was reconstituted into membranes pretreated with NEM, the kappa-receptor-mediated inhibition was recovered. These findings suggest that a subtype of kappa-opioid receptor is coupled to inhibition of intrinsic activity of Gi1.

Animals↗
PubMed1996

Expression of mRNA encoding neurotrophic factors and its regulation in a hybrid neuronal cell line.

In a cultured hybrid neuronal cell line (BIM) which was produced between human neuroblastoma cells (IMR32) and thymidine auxotrophs (B3T) of rat nerve-like cells (B103), the mRNAs encoding ciliary neurotrophic factor (CNTF) and neurotrophins were detected by the polymerase chain reaction method. The conditioned medium of BIM cells enhanced choline acetyltransferase (ChAT) activity in septal neurons and survival of ciliary ganglion neurons. The mRNA expression of CNTF and neurotrophins in BIM cells was differently regulated by the stimulation with cAMP, FGF and retinoic acid. These data suggest multiple regulation and collaboration of neurotrophic factors.

Animals↗
PubMed1996

[Estimation of SIDS with measurement of cardio-respiratory contribution ratio through multivariate autoregressive modelling approach].

We obtained the cardio-respiratory impulse response and noise contribution ratio to study the central respiratory control system in one case of Ondine's curse, one case of sleep apnea syndrome and 34 cases of preterm infants, using multivariate autoregressive analysis. In Ondine's curse, the noise contribution ratio decreased during sleep. In the sleep apnea syndrome, the noise contribution ratio before apnea and after apnea decreased. In the preterm infants, the noise contribution ratio increased with the conceptional age. From these results, we concluded that the central cardio-respiratory control system was disturbed in Ondine's curse, sleep apnea syndrome and preterm infants. The cardio-respiratory impulse response using a multiple autoregressive analysis was useful for prediction of sudden infant death syndrome.

Heart Rate↗
PubMed1996

[Repair of total anomalous pulmonary venous return using an ultra-short acting beta blockade (esmolol)--case reports].

In 2 infants with asplenic syndrome associated with total anomalous pulmonary venous return (TAPVR), a repair of TAPVR was done under mild hypothermic cardiopulmonary bypass (CPB) using esmolol, an ultra short-acting beta-blocker to obtain good operative field without aortic-cross clamping. Both cases were weaned from CPB uneventfully. Pulmonary venous obstruction was not found after surgery. This strategy seems to be applicable in pediatric cardiac surgery which is mainly limited to the atrial level.

Adrenergic beta-Antagonists↗
PubMed1996

[A case of ventricular septal defect closure in patient with cytomegalo virus hepatitis].

Cytomegalovirus (CMV) infection has been reported to cause serious event in nonimmunocompromised patients after major surgery. Particularly in active case, the indication of surgical intervention is a difficult issue. A 7-months-old boy with ventricular septaldefect (VSD) has been diagnosed with CMV hepatitis. As his heart failure was not controlled with medication, he underwent closure of VSD at 9 months of age while CMV was still detected in the urine and serum by polymerase chain reaction method. During post operative course, he was treated with ganciclovir and intravenous CMV hyperimmune grobiln, and CMV in the serum became negative and he develops no aggravation of the CMV infection postoperatively.

Antiviral Agents↗
PubMed1996

[Heart transplantation].

Heart transplantation was introduced clinically in 1964 by Hardy using a Chimpanzee heart. Since the standard method had been established by Shumway and cyclosporine had been introduced in 1982, patient numbers increased rapidly. Because of donor shortage, patient numbers have been about 3,000 to 3,500 in these 8 years. According to the registry of the International Society for Heart and Lung Transplantation, 1 and 3 year survival rate were 80% and 73%, respectively. We hope to start heart transplantation as soon as possible in Japan.

Costs and Cost Analysis↗
PubMed1995

Evidence for a metabostatic opioid kappa-receptor inhibiting pertussis toxin-sensitive metabotropic glutamate receptor-currents in Xenopus oocytes.

Glutamate evoked pertussis toxin-sensitive currents in Xenopus oocytes expressing metabotropic glutamate receptor subtype 1 (mGluR1) and exogenous Gi1 alpha. The mGluR1-currents were completely blocked by U-73122, a phospholipase C (PLC) inhibitor and by niflumic acid, a chloride channel blocker. In the oocyte further coinjected with poly(A)+ RNA from the guinea pig cerebellum, the mGluR1-currents were inhibited by U-50488H, an opioid kappa-agonist, and this inhibition was blocked by norbinaltorphimine, an opioid kappa-antagonist. These findings suggest that the mRNA encoding a novel subtype of opioid kappa-receptor which inhibits Gi1-PLC-mediated currents is present in guinea pig cerebellar poly(A)+ fractions.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗