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Biomedical subjects

N Fukushima

Publications and source records attributed to N Fukushima.

At least 145 records · Page 8Linked to original sources

Correlation between immunophenotypic diversity and clinical features in B-cell lymphoblastic lymphoma.

Lymphoblastic lymphoma (LBL) is a highly malignant subtype of non-Hodgkin's lymphoma (NHL) and generally carries a T-cell phenotype with mediastinum or central nervous system (CNS) involvement. However, only a small proportion of LBL exhibit a B-cell phenotype (B-LBL), and these frequently present at the head and neck without mediastinum or CNS involvement. Three immunological subgroups may exist. The most predominant CD10-positive pre-B-cell type, corresponding to a precursor B-cell neoplasm, frequently involves the head and neck. The second, CD10-negative or mature B-cell type, defined by the absence of CD10 or presence of surface membrane immunoglobulins combined with expression of CD19 or CD20, often involves the mediastinum. The final group is a CD5-positive B-cell type corresponding to a blastic variant of mantle cell lymphoma (MCL). Its clinical course is less aggressive, patients are often older, and nodal lesions are more frequent than extranodal involvement. Thus, B-LBL is immunologically diverse, but its biological behavior correlates with the immunophenotype.

Adolescent↗

Growth of oversized grafts in neonatal heart transplantation.

BACKGROUND: Because of the severe shortage of neonatal organ donors, oversized cardiac allografts are frequently transplanted. This study examined body and graft growth of neonates who receive an oversized heart. METHODS: We studied 51 neonates, who received transplants between November 1986 and August 1992, for changes in body weight, left ventricular mass, and end-diastolic volume measured at 1 week, 1, 3, and 6 months, and yearly after cardiac transplantation. Patients were divided into two groups according to donor/recipient weight ratios: the normal group, where the donor/recipient weight ratio was 1.5 or less (1.06 +/- 0.05; n = 24), and the oversized group, where the donor/recipient weight ratio was more than 1.5 (2.22 +/- 0.10; n = 27). RESULTS: After cardiac transplantation, body weight increased continuously in both groups with no difference between groups. In the oversized group, left ventricular end-diastolic volume at 1 week and left ventricular mass at 1 week and 1 month were significantly higher than those in the normal group (p < 0.01). In the normal group, end-diastolic volume and left ventricular mass increased continuously. In the oversized group, however, left ventricular mass significantly decreased until 3 months after cardiac transplantation and then increased continuously, whereas end-diastolic volume increased continuously throughout the posttransplantation period. CONCLUSIONS: These data suggest that oversized cardiac allografts shrink at first and then grow as the recipient grows. There appears to be a size adaptation of the large cardiac allograft to accommodate to the reduced requirements of the neonate.

Body Surface Area↗

Serum lipoprotein(a) levels before and after subtotal thyroidectomy in subjects with hyperthyroidism.

Lipoprotein(a) [Lp(a)], a lipoprotein that structurally resembles low-density lipoprotein (LDL), contains apolipoprotein(a) [apo(a)] and apolipoprotein B-100 (apo B). There exists a close inverse correlation between serum concentrations of LDL or apo B and concentrations of thyroid hormone in patients with thyroid disease, probably due to a change in LDL receptor activity. To clarify the relations between thyroid hormone and Lp(a), we measured serum Lp(a) levels in 13 hyperthyroid subjects before treatment (stage H), during the euthyroid stage induced immediately before performing a subtotal thyroidectomy (stage E), and during the hypothyroid stage observed transiently after the operation (stage L). The mean serum concentration of Lp(a) increased significantly (P = .01) from 9.4 mg/dL in stage H to 26.8 in stage L through the level of 15.5 mg/dL in stage E. There was no significant difference between the mean serum concentration of Lp(a) in these patients in stage E and healthy controls (14.2 mg/dL). There was a low but statistically significant negative correlation between the Lp(a) level and the serum free thyroxine (fT4) concentration (r = .31, P < .05). The results suggest that thyroid hormone is a potent modulator of Lp(a) metabolism.

Adult↗

Opioid mu- and kappa-receptor mediate phospholipase C activation through Gi1 in Xenopus oocytes.

In the Xenopus oocytes expressing mu- or kappa-opioid receptors, agonist-induced currents were observed only when the oocyte was coinjected with Gi1 alpha RNA and pretreated with K-252a, a potent inhibitor of protein kinases. The evoked currents were abolished by intracellular injection of EGTA or inositol 1,4,5-trisphosphate and the current-voltage relationship revealed that they are mediated through typical calcium-dependent chloride channels. These findings suggest that the mu- and kappa-receptors mediate phospholipase C activation through Gi1 alpha, and that these receptor mechanisms including downstream signalings might be inhibited by phosphorylation in vivo in the Xenopus oocyte.

Animals↗

Protein kinase C inhibitor potentiates the agonist-induced GTPase activity in COS cell membranes expressing delta-opioid receptor.

In COS-7 cell membranes expressing cloned delta-opioid receptor, [D-Ser2, Leu5]enkephalin-Thr6, an opioid delta-agonist, showed no significant stimulation of high-affinity GTPase, while this agonist binding showed a guanine nucleotide sensitivity. Significant stimulation of GTPase activity by this agonist was observed only when the cells were pretreated with 0.1 microM calphostin C, a protein kinase C inhibitor, and when this inhibitor was further added to the reaction mixture at 1 microM. These findings suggest that protein kinase C is involved in the heterologous desensitization of delta-opioid receptor in the cells.

Analgesics↗

Pharmacological effects of dai-saiko-to on lipid biosynthesis in cultured human hepatocyte HepG2 cells.

The pharmacological effects of Dai-saiko-to, a Japanese and Chinese traditional medicinal mixture (Kampohozai), on lipid biosynthesis were investigated in cultured human hepatocyte HepG2 cells. The addition of Dai-saiko-to (0.5 mg/ml), which had no significant effect on cell proliferation, caused a marked decrease in the intracellular triglyceride content with no significant changes in the other lipid fraction. At the same time, the incorporation of 14C-acetate or 3H-glycerol into the triglyceride or diglyceride fractions also decreased significantly. These results suggest that Dai-saiko-to decreases hepatic triglyceride biosynthesis, which might contribute to a reduction in plasma VLDL levels.

Cell Division↗

Successful survival of primates receiving transplantation with "dead," nonbeating donor hearts.

A paucity of donor organs is the principal limitation in human heart transplantation. Prompted by our short-term studies of reanimating "dead" donor hearts in sheep, we applied the same reperfusion modifications in juvenile baboons to determine human applications in an anoxic arrest model (as occurs when non-brain-dead patients are extubated and allowed to die). Ten juvenile baboons (mean weight 3.6 kg) were studied. Five baboons were used as donors. After being anesthetized, donors were pretreated with methylprednisolone (Solu-Medrol), 50% dextrose, nifedipine, and prostaglandin E1 and then paralyzed and extubated. Donors became pulseless at 7 +/- 1 minutes and had electric arrest 9 to 18 minutes after paralysis. The five donors were left undisturbed and warm for 15, 22, 30, 30, and 31 minutes, respectively, after asystole. They were then given 250 ml of 4 degrees C Roe's crystalloid cardioplegic solution via the aortic root and the hearts were explanted into iced Euro-Collins solution. Five baboons served as recipients. After donor harvest, recipients were placed on cardiopulmonary bypass, given prostaglandin E1, and cooled to 18 degrees C; circulatory arrest was instituted and the recipient's heart excised. The donor heart was transplanted in an orthotopic position. Before reinstitution of bypass, 250 ml of terminal leukocyte-depleted blood cardioplegic solution was given, then bypass was restarted and the hearts were reperfused for 60 minutes. All animals were weaned from bypass without the use of inotropic agents. All animals were extubated within 2 to 4 hours after bypass and received standard immunosuppression. Peak creatine kinase MB/total creatine kinase ratio was 0.2% +/- 0.2%. Postoperative ejection fractions by echocardiography were 75% to 80% (mean 76%). Animals survived 1, 9, 13, 16, and 34 days, with three deaths caused by acute rejection and one each by stroke and diarrhea/dehydration. Pathologic findings showed no areas of fibrosis or ischemic damage. We conclude that successful reanimation and engraftment can be achieved with the use of the asystolic primate heart; this work suggests that human application is realistic and could greatly expand the donor pool.

Animals↗

Establishment and structural analysis of human mAb to the E2 component of the 2-oxoglutarate dehydrogenase complex generated from a patient with primary biliary cirrhosis.

We established one Epstein-Barr virus-transformed B cell hybrid clone producing human mAb of the IgG class to the 2-oxoglutarate dehydrogenase complex (OGDC) for the first time from the peripheral B lymphocytes of a patient with primary biliary cirrhosis (PBC). This mAb, designated mAbM37GO37, specifically bound to OGDC and its dissociation constant with OGDC was calculated to be 3.70 x 10(-10) mol/l. mAbM37GO37 stained murine stomach/kidney cryostat sections in a typical immunofluorescence pattern of antimitochondrial antibody (AMA). Western blotting analysis revealed that mAbM37GO37 reacted with an E2 component of OGDC but not with other components of OGDC nor pyruvate dehydrogenase complex (PDC). Furthermore, mAbM37GO37 completely inhibited the enzymatic activity of OGDC. In order to determine the structure and genetic origin of anti-OGDC autoantibody, we cloned and sequenced the Ig heavy and light chain variable regions of mAbM37GO37. This mAb used the VHIII family member, V3-7, and the V kappa IV family member. The amino acid difference between the expressed V genes of this mAb and respective putative germline genes was concentrated within the complementarity determining regions (CDR) rather than the framework regions (FR). The R:S mutation ratio was high in the CDR and low in the FR. These features suggested that the immune response to OGDC is similar to that to exogenous antigen, and that the heavy and light chain variable regions of the anti-OGDC antibody undergo somatic hypermutation through antigen-driven clonal selection. This human mAb to OGDC, which was established for the first time from a patient with PBC and characterized at the molecular level, would be a valuable tool to study the B cell autoepitopes of OGDC, to clone as yet undetermined full length cDNA encoding OGDC and to dissect the autoimmune response to mitochondrial antigens in PBC.

Adult↗

Mesothelial cyst of the adrenal gland.

A case of mesothelium-lined cyst of the adrenal gland is reported. Although more than 300 adrenal cysts have been reported in the literature, epithelial cell-lined cysts are rare and comprise only 9% of the cases. An adrenal cyst was found, the lining cells of which had features consistent with mesothelial cells. The inner surface of the cyst was lined by a single layer of cuboidal cells, which showed alcian blue positive cellular outline. Immunohistochemically, the lining cells were positively stained for keratin, epithelial membrane antigen and CA-125. Electron microscopic examination revealed many long complex microvilli and desmosomes in the lining cells. There was a basal lamina beneath the cell layer. These morphological and immunohistochemical findings indicated that the lining cell is derived from mesothelium.

Adrenal Gland Diseases↗

The occurrence of nicked human chorionic gonadotropin (hCG) by a thermolytic endoprotease.

A nicked form of human chorionic gonadotropin (nicked hCG), in which only one peptide bond between residues 47 and 48 (-Gly-Val-) of beta-subunit is cleaved, has been found in the urine and blood of pregnant women. In this study, we investigated the occurrence of nicked hCG and the localization of the nicking enzyme for hCG. First, to determine what type of protease nicks hCG, an in vitro proteolytic study using various proteases was performed. Amino-terminal amino acid sequence analysis of the beta-subunit purified from protease-treated hCG indicated that thermolysin actively nicks hCG. Secondly, to determine which tissues are related to the formation of nicked hCG, the distribution of radioactivity in various tissues after i.v. administration of radiolabeled hCG to female rats was examined. The radioactivity accumulated predominantly in the kidney (17%), liver (9.3%) and ovary (0.9%) after 30 min of injection. Analysis of molecular species of beta-radiolabeled hCG in various tissues and body fluids, using sodium dodecyl sulfate polyacrylamide gel electrophoresis followed by autoradiography, indicated that a nicked hCG-like molecule was found in the kidney, predominantly, as well as in the serum and urine. To examine the role of the kidney in producing nicked hCG, hCG was incubated with rat kidney particulate fraction (KPF). Immunoblot analysis of KPF-treated hCG indicated that KPF produced a nicked hCG-like molecule. Furthermore, the possibility that placental trophoblast cells produce nicked hCG was also examined using the choriocarcinoma cell BeWo.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

Protein kinase C involvement in homologous desensitization of delta-opioid receptor coupled to Gi1-phospholipase C activation in Xenopus oocytes.

We have developed the coexpression system of both delta-opioid receptor (DOR1) and M2-muscarinic receptor (M2) which mediate agonist-evoked currents due to common post-receptor mechanisms including Gi1 and phospholipase C (PLC) activation in Xenopus oocytes reconstituted with Gi1 alpha. The DOR1-currents by 100 nM D-Ser2-leu-enkephalin-Thr6 (DSLET) were selectively desensitized by 10 nM phorbol 12-myristate 13-acetate (PMA). The PMA-desensitization of DSLET-currents was abolished in the presence of calphostin C, a protein kinase C inhibitor, or reversed by an intracellular injection of calcineurin, a protein phosphatase 2B. When a higher concentration (3 microM) of DSLET was used, DSLET-currents were rapidly desensitized by repeated challenges of DSLET itself. However, repeated challenges of 10 microM ACh caused no influence on such DSLET- or M2-currents. The desensitization of DSLET-currents was selectively reversed by protein kinase C inhibitors. Similar results were also obtained with various delta-opioid agonists. These results suggest that protein kinase C is involved in the homologous desensitization of delta-opioid receptors.

Animals↗

[Non-Fukuyama type merosin-positive congenital muscular dystrophy with delayed muscle fiber type differentiation: a case report].

A patient with non-Fukuyama type merosin-positive congenital muscular dystrophy (nonFCMD) who had severe muscle weakness leading to early death was reported. He was the first product of epileptic mother who had been placed on phenobarbital and phenytoin. The patient had severe respiratory failure and muscle weakness at the neonatal period, and died at 4 months of age. Multiple joint contractures were also noted at birth. Serum creatine kinase was within normal limits (123 IU/l). Electromyography showed a myogenic pattern. Brain computed tomographic (CT) scan and magnetic resonance imaging (MRI) were normal without white matter lucency or pachygyria. Muscle biopsy revealed dystrophic changes and type 2C fiber predominance. Dystrophin, dystrophin-associated glycoproteins and merosin were all positively demonstrated. Although patients with merosin-positive nonFCMD have relatively mild clinical course, our patient had severe muscle weakness with fatal outcome. Defect in muscle fiber maturation and differentiation, such as an increase of undifferentiated type 2C fibers, may be a major factor to influence muscle symptoms in non FCMD.

Humans↗

[Multivariate autoregressive analysis of carotid artery blood flow waveform in a newborn with multicystic encephalomalacia].

We analyzed the carotid artery blood flow waveform (CABFW) through multivariate autoregressive analysis in a case with multicystic encephalomalacia (MCE) after neonatal asphyxia and compared the result with those of 35 healthy newborns. The total power of CABFW was at the -2 SD level of the value for 35 healthy newborns, and the power, % power, bio-informing amounts and damping time of component 3 (damping frequency 11.15 Hz) were less than -2 SD of the values in 35 healthy newborns. The Pulsatility Index (PI) of anterior cerebral artery (ACA) was high (0.76). These results suggest that cerebral blood flow decreases because of cerebral vasoconstriction in MCE after neonatal asphyxia.

Brain Diseases↗

[Comprehensive evaluation of pharmacokinetic and clinical studies on tazobactam/piperacillin in pediatric field].

To evaluate the pharmacokinetic and clinical effects of the newly developed combination antibiotic tazobactam/piperacillin (TAZ/PIPC, YP-14) on various infections in pediatric field, a study group was organized, and a joint research by 17 institutions and their related hospitals was conducted. Informed consents of subjects were obtained prior to the study. The results obtained in this study are as follows: 1. Blood concentration and urinary excretion Pharmacokinetics of TAZ/PIPC was studied in children at doses of 25 and 50 mg/kg through intravenous injection or intravenous drip infusion. With intravenous injection, maximum blood concentrations (Cmax's) of TAZ and PIPC were achieved 5 minutes after the administration. Cmax's of TAZ were 26.9 micrograms/ml with 25 mg/kg and 45.1 micrograms/ml with 50 mg/kg, and those of PIPC were 131.0 and 199.6 micrograms/ml, respectively. Values of the total area under the blood concentration curve (AUC's) of TAZ were 14.2 micrograms.hr/ml with 25 mg/kg and 26.1 micrograms.hr/ml with 50 mg/kg, and those of PIPC were 64.0 and 112.8 micrograms.hr/ml, respectively; thus dose dependency was observed with both TAZ and PIPC. The Cmax's of desethyl piperacillin (DEt-PIPC), the active metabolite of PIPC, achieved at 60 minutes after administration, were 1.2 and 2.0 micrograms/ml, respectively. The AUC's of DEt-PIPC were 2.6 and 4.2 micrograms.hr/ml, respectively. The half-lives (T 1/2's) of TAZ were 0.60 and 0.54 hour, respectively, and those of PIPC were 0.62 and 0.65 hour, respectively. In the first 6 hours after the initiation of administration, the cumulative recovery rates of TAZ in the urine were 46.7 and 56.0% respectively, those of PIPC were 46.1 and 57.2%, respectively, and those of DEt-PIPC were 5.9 and 3.0%, respectively. With intravenous drip infusion, the Cmax's of both TAZ and PIPC were achieved at the completion of drip; the Cmax's of TAZ were 12.1 micrograms/ml with 25 mg/kg and 28.9 micrograms/ml with 50 mg/kg, and those of PIPC were 54.6 and 137.9 micrograms/ml, respectively. The AUC's of TAZ were 11.6 micrograms.hr/ml with 25 mg/kg and 25.6 micrograms.hr/ml with 50 mg/kg, and those of PIPC were 49.0 and 117.2 micrograms.hr/ml, respectively; thus dose dependency was observed with both TAZ and PIPC. Cmax's of DEt-PIPC, achieved at 60 minutes after completion of drip, were 0.9 and 1.7 micrograms/ml, respectively. The AUC's of DEt-PIPC were 2.0 and 3.8 micrograms.hr/ml, respectively. The half-lives (T 1/2's) of TAZ were 0.59 and 0.62 hour, respectively, and those of PIPC were 0.58 and 0.57 hour, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

[Relative size of the ventricle to the hemisphere in the neonatal MRI].

Using a software program for measuring surface area, we quantified the relative size of four parts of the lateral ventricles, including the body, the trigone, the anterior horn and the occipital horn, compared to the hemispheres in the axial plane of magnetic resonance imaging (MRI) in neonates. In 44 neonates without any neurological disorders from 26 to 41 weeks of gestational age (GA), MRI was performed between 12 and 124 postnatal days. The mean of the relative size of the ventricle compared to the hemisphere (RSVH) among the subjects showed a significant left-right asymmetry that was observed only in the occipital horn. However, in the body, the anterior horn and the occipital horn, the percentage of neonates with a larger left RSVH compared to the right RSVH was significantly higher than the percentage of neonates with a larger right RSVH compared to the left RSVH. The RSVH of the body and the occipital horn increased according to the number of postnatal days and decreased according to GA. Measuring RSVH was useful in assessing the size of the ventricle in the axial plane of neonatal MRI. It clarified the fact that normative asymmetry, GA of subject, and the number of postnatal days should be considered in assessing the size of ventricle.

Cerebral Ventricles↗

Protein kinase inhibitor potentiates opioid delta-receptor currents in Xenopus oocytes.

In Xenopus oocytes injected with RNA coding for the delta-opioid receptor a small chloride current was evoked by [D-Ala2,Ser5]leucine-enkephaline-Thr6 (DSLET), a delta 2-opioid agonist. The evoked currents were rapidly reduced upon repeated challenges of DSLET. When Gil alpha RNA was co-injected into the oocyte, the evoked currents were increased 3.8-fold and became constant after at least three repeated challenges. In oocytes injected with RNAs coding for delta-receptor and Gil alpha, pretreatment with K-252a, a potent inhibitor of protein kinases, further potentiated the delta-receptor-mediated current responses, compared with those without the inhibitor. These results suggest that signalling involving the delta-opioid receptor is inactivated through in vivo phosphorylation in the Xenopus oocyte.

Analgesics↗

Species and age-dependent differences of functional coupling between opioid delta-receptor and G-proteins and possible involvement of protein kinase C in striatal membranes.

[D-Ser2,Leu5]-enkephalin-Thr6 (DSLET) and [D-Pen2,5]-enkephalin (DPDPE), both delta-agonists, stimulated the high affinity GTPase in the rat striatal membranes in a naltrindole-reversible manner. Similar stimulation was also observed in the striatal membrane preparations of 16-week-old guinea pigs, while not in those preparations of 4-week-old ones. When calphostin C, a protein kinase C inhibitor, was added to the reaction mixture, DSLET showed a marked stimulation in this activity in 4-week guinea pig striatal membranes. There was no effect of KT5720, a cyclic AMP-dependent protein kinase inhibitor, on such delta-opioid-mediated responses. These findings suggest that protein kinase C is locally involved in the functional uncoupling of delta-receptors to G-proteins in the striatum of young guinea pigs.

Aging↗