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E Nishimura

Publications and source records attributed to E Nishimura.

At least 19 recordsLinked to original sources
PubMed2001

Surface analysis of Ti-15Zr-4Nb-4Ta alloy after implantation in rat tibia.

A new Ti-15Zr-4Nb4Ta alloy without V was implanted in rat tibiae for 6-48 weeks. The new bone formation surrounding the Ti implant in bone marrow, surface analysis of the Ti alloy after implantation, and metal concentrations in dried bone tissue containing new bone were investigated. New bone was well formed around the Ti-15Zr-4Nb-4Ta alloy implanted in bone marrow. The mean thickness of the new bone increased up to 24 weeks after implantation, and changes in the mean thickness thereafter, up to 48 weeks. were very small. The number of corrosion pits observed in the Ti-6Al-4V extra low interstitial (ELI) alloy surface tended to be slightly more than that of the Ti-5Zr-4Nb-4Ta alloy implant. The concentrations of metal elements in the bone tissue containing the new bone tended to increase slightly more than in bones without the implant.

Alloys↗
PubMed2001

[No relation between angiotensin-converting enzyme (ACE) inhibitor-induced cough and ACE gene polymorphism, plasma bradykinin, substance P and ACE inhibitor concentration in Japanese patients].

Persistent dry cough is well known as the most common side-effect of angiotensin-converting enzyme (ACE) inhibitors. We examined the relationship between a cough and ACE gene polymorphism, plasma bradykinin (BK), substance P (SP) and ACE inhibitor concentrations in patients with hypertension or chronic nephritis. First, ACE genotyping was carried out in 96 patients, 42 with coughs and 54 without coughs, which had been treated with various kinds of ACE inhibitors. However, no significant difference in the ACE genotypes was observed between the two groups. Second, the plasma concentrations of BK, SP and ACE inhibitor were measured in 12 patients, which were treated with trandolapril at a daily dose of 1 mg for 4-33 weeks. In 3 patients, the cough was induced during the trandolapril therapy, while it was induced not in 9 patients. The plasma levels of BK and SP did not significantly change after trandolapril administration in the patients with and without coughs. Between the two groups, there were no significant differences in the plasma levels of BK and SP either before or after the trandolapril therapy. Also the plasma concentrations of trandolapril and trandolaprilat, the active metabolite of trandolapril, did not significantly differ between the two groups. These results suggest that there is no significant relationship between the ACE inhibitor-induced cough and ACE gene polymorphism, plasma BK, SP and ACE inhibitor concentrations in patients with hypertension or chronic nephritis.

Aged↗
PubMed2001

Diagnostic value of pulsed Doppler echocardiography in acute pulmonary thromboembolism--comparison with pulmonary angiography and pulmonary artery pressure.

The ratio of acceleration time to right ventricular ejection time (AcT/RVET) can be derived from the blood flow patterns recorded by pulsed wave Doppler echocardiography. In chronic cor pulmonale, AcT/RVET negatively correlates with pulmonary artery pressure (PAP). The present study evaluated the diagnostic value of AcT/RVET by comparing this variable with indices derived from pulmonary angiography (PAG) and PAP in 16 patients with acute pulmonary thromboembolism (APTE). AcT/RVET, PAP, and PAG severity indices (Miller index (MI) and UPET objective angiographic index (UI)) were measured during the acute phase on admission and the chronic phase after treatment. In the acute phase, AcT/RVET correlated with mean PAP (mPAP) (r=-0.68, p<0.05) and total pulmonary resistance (TPR) (r=-0.66, p<0.05), but not with MI or UI. During the chronic phase, AcT/RVET did not correlate with mPAP or TPR, but with both PAG indices (MI: r=0.76, p<0.05, UI: r=0.65, p<0.05). Before treatment of the APTE, AcT/RVET remained at low levels and could be used as an index of pulmonary hypertension. After treatment, however, following improvement of PAP, AcT/RVET was not useful for evaluating PAP, but might serve as an index for evaluating the volume of residual thrombi.

Acute Disease↗
PubMed2001

[Recurrence of bullous pemphigoid after surgery: report of a case].

We report a 38-year-old woman with myoma uteri and bullous pemphigoid controlled by oral prednisolone (7.5 mg.day-1). She underwent transabdominal hysterectomy under epidural anesthesia using mepivacaine supplemented with intravenous midazolam and butorphanol, without untoward event. On the postoperative day 2, recurrence of bullous pemphigoid was noted. The skin lesion of pemphigoid was improved after increasing the prednisolone dose up to 60 mg a day.

Adult↗
PubMed2000

Dipeptidyl peptidase IV (DPIV/CD26) degradation of glucagon. Characterization of glucagon degradation products and DPIV-resistant analogs.

Over the past decade, numerous studies have been targeted at defining structure-activity relationships of glucagon. Recently, we have found that glucagon(1-29) is hydrolyzed by dipeptidyl peptidase IV (DPIV) to produce glucagon(3-29) and glucagon(5-29); in human serum, [pyroglutamyl (pGlu)(3)]glucagon(3-29) is formed from glucagon(3-29), and this prevents further hydrolysis of glucagon by DPIV (H.-U. Demuth, K. Glund, U. Heiser, J. Pospisilik, S. Hinke, T. Hoffmann, F. Rosche, D. Schlenzig, M. Wermann, C. McIntosh, and R. Pederson, manuscript in preparation). In the current study, the biological activity of these peptides was examined in vitro. The amino-terminally truncated peptides all behaved as partial agonists in cyclic AMP stimulation assays, with Chinese hamster ovary K1 cells overexpressing the human glucagon receptor (potency: glucagon(1-29) > [pGlu(3)]glu- cagon(3-29) > glucagon(3-29) > glucagon(5-29) > [Glu(9)]glu- cagon(2-29)). In competition binding experiments, [pGlu(3)]glucagon(3-29) and glucagon(5-29) both demonstrated 5-fold lower affinity for the receptor than glucagon(1-29), whereas glucagon(3-29) exhibited 18-fold lower affinity. Of the peptides tested, only glucagon(5-29) showed antagonist activity, and this was weak compared with the classical glucagon antagonist, [Glu(9)]glucagon(2-29). Hence, DPIV hydrolysis of glucagon yields low affinity agonists of the glucagon receptor. As a corollary to evidence indicating that DPIV degrades glucagon (Demuth, et al., manuscript in preparation), DPIV-resistant analogs were synthesized. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry was used to assess DPIV resistance, and it allowed kinetic analysis of degradation. Of several analogs generated, only [D-Ser(2)] and [Gly(2)]glucagon retained high affinity binding and biological potency, similar to native glucagon in vitro. [D-Ser(2)]Glucagon exhibited enhanced hyperglycemic activity in a bioassay, whereas [Gly(2)]glucagon was not completely resistant to DPIV degradation.

Animals↗
PubMed2000

Left ventricular mass and global function in essential hypertension after antihypertensive therapy.

This study compares left ventricular global function in 55 patients (25 with hypertrophy and 30 without hypertrophy) with essential hypertension, whose blood pressure had been stable for longer than 1 year, with that in 35 healthy subjects. Left ventricular global function was calculated using the echocardiographic Doppler index as described by Tei et al. (Tei index). No significant differences were observed in echocardiographic left ventricular systolic function between the three groups. Left ventricular global function differed significantly between the three groups, however, suggesting impaired left ventricular global function even in the absence of left ventricular hypertrophy. Similar changes were observed in the ratio of peak velocity of atrial systole to peak velocity of early diastole during left ventricular inflow waveform (A/E), indicating that this disorder mainly reflects impaired left ventricular diastolic function. Unlike A/E, the Tei index is not affected by increasing age, and, therefore, is appropriate for evaluating left ventricular global function in hypertensive patients, most of whom are middle-aged or older. This index may be useful for determining treatment strategy and evaluating treatment effects.

Adrenergic beta-Antagonists↗
PubMed1999

Serial changes in negative T wave on electrocardiogram in acute pulmonary thromboembolism.

A negative T wave is frequently observed in precordial ECG leads in patients with acute pulmonary thromboembolism. We investigated the clinical significance of negative T wave in 15 patients with acute pulmonary thromboembolism who were treated with thrombolytic agents by measuring the mean pulmonary artery pressure and ratio of right to left ventricular end-diastolic diameter using echocardiography and ECG. The study included only patients with massive acute pulmonary thromboembolism of a mean age of 65+/-9.7 years (+/-SD). A negative T wave was observed on admission in 10 patients but was later detected in 14 of the 15 patients. The mean amplitude of the negative T wave increased within 1 week then decreased after thrombolytic treatment. The peak negative amplitude of the T wave was observed from 1 to 7 days (mean, 2.6+/-1.8 days) and disappeared afterwards. During this period, improvements in both the mean pulmonary artery pressure (37.8+/-11.2 to 19.1+/-6.7 mmHg) and the ratio of right to left ventricular end-diastolic diameter (0.97+/-0.16 to 0.51+/-0.13) were noted in all patients. Our results suggest that an increase in the amplitude of negative T wave in precordial leads after thrombolytic therapy in patients with massive acute pulmonary thromboembolism reflects improvement in cardiopulmonary hemodynamics.

Aged↗
PubMed1999

Recombinant light chain of human monoclonal antibody HB4C5 as a potentially useful lung cancer-targeting vehicle.

Recombinant lambda light chain of lung cancer-reacting human monoclonal antibody HB4C5 was expressed in Escherichia coli. Expression in bacteria ensured the generation of homogeneous light chain species devoid of activity-hampering N-linked glycosylation usually found in the light chain CDR-1 of HB4C5. Molecular engineering was also employed to eliminate the C-terminal two amino acid residues, i.e., Cys and Ser, to prevent the formation of lambda light chain dimers which are less reactive than the monomeric form. The lambda light chain was overexpressed in E. coli as inclusion bodies, which were solubilized, refolded, and treated with Aeromonas proteolytica aminopeptidase to remove the N-terminal Met with subsequent natural cyclization of the penultimate Gln residue to pyroglutamate, the same N-terminal end as that of naturally occurring lambda light chain in HB4C5. Monomeric recombinant lambda light chains, both before and after removal of the N-terminal Met residue, were 40 times more immunoreactive than the parent HB4C5. The immunostaining of lung cancer tissue sections with the recombinant lambda light chain indicated cancer-specific reactions to all specimens of adenocarcinoma, squamous cell carcinoma and large cell carcinoma histologies, but did not react with small cell carcinoma. Tumor radioimmunoimaging experiments in LC6 (lung squamous cell carcinoma line)--xenografted nude mice by the i.p. injection of 125I-labeled recombinant lambda light chain and 125I-labeled human lambda light chain control gave tumor-specific and recombinant lambda light chain-dependent images on day 5 postinjection, and images were also detectable on day 3. Biodistribution studies with 125I-labeled recombinant lambda light chain demonstrated that the lambda light chain could penetrate better into the tumor sites, both at the necrotic and solid parts of the xenograft, as compared to our previous results with 125I-labeled HB4C5 which could localize to the necrotic part only. These results suggest that the recombinant lambda light chain is potentially useful as a lung cancer-targeting vehicle, for such as radioimmunoimaging and radioimmunotherapy, with least possible adverse immunogenic effects.

Amino Acid Sequence↗
PubMed1998

Analysis of preoperative factors predictive of visual acuity in axial myopia.

PURPOSE: To identify the factors predicting visual acuity after cataract surgery in patients with high myopia. SETTING: Departments of Ophthalmology, Showa University School of Medicine and Showa University Fujigaoka Hospital, Kanagawa, Japan. METHODS: Stepwise regression analysis was used to identify the factors determining the visual acuity in 940 eyes with an axial length of 27.0 mm or longer having cataract surgery. Using a formula derived from the stepwise regression analysis, the predicted postoperative visual acuity was compared with the actual value measured in another group of 104 eyes. RESULTS: Five factors were identified to significantly determine postoperative visual acuity: axial length, age, corneal opacity, refractive power of the cornea, and history of retinal detachment surgery. There was a significant relationship between predicted and actual postoperative visual acuities (r = .51, P < .001). Postoperative visual acuity was similar in 63% of cases. CONCLUSION: The results showed that at least five factors determine visual acuity after cataract surgery in patients with high myopia.

Adolescent↗
PubMed1998

Glucagon-mediated Ca2+ signaling in BHK cells expressing cloned human glucagon receptors.

From video imaging of fura 2-loaded baby hamster kidney (BHK) cells stably expressing the cloned human glucagon receptor, we found the Ca2+ response to glucagon to be specific, dose dependent, synchronous, sensitive to pertussis toxin, and independent of Ca2+ influx. Forskolin did not elicit a Ca2+ response, but treatment with a protein kinase A inhibitor, the Rp diastereomer of 8-bromoadenosine-3',5'-cyclic monophosphothioate, resulted in a reduced glucagon-mediated Ca2+ response as well as Ca2+ oscillations. The specific phospholipase C inhibitor U-73122 abolished the Ca2+ response to glucagon, and a modest twofold increase in inositol trisphosphate (IP3) production could be observed after stimulation with glucagon. In BHK cells coexpressing glucagon and muscarinic (M1) acetylcholine receptors, carbachol blocked the rise in intracellular free Ca2+ concentrations in response to glucagon, whereas glucagon did not affect the carbachol-induced increase in Ca2+. Furthermore, carbachol, but not glucagon, could block thapsigargin-activated increases in intracellular free Ca2+ concentration. These results indicate that, in BHK cells, glucagon receptors can activate not only adenylate cyclase but also a second independent G protein-coupled pathway that leads to the stimulation of phospholipase C and the release of Ca2+ from IP3-sensitive intracellular Ca2+ stores. Finally, we provide evidence to suggest that cAMP potentiates the IP3-mediated effects on intracellular Ca2+ handling.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1998

Transgene expression of steel factor in the basal layer of epidermis promotes survival, proliferation, differentiation and migration of melanocyte precursors.

Mutations at the murine dominant white spotting (KitW) and steel (MgfSl) loci, encoding c-Kit receptor kinase and its ligand respectively, exert developmental defects on hematopoietic cells, melanocytes, germ cells and interstitial cells of Cajal. The expression patterns of steel factor (SLF) observed in the skin and gonads suggest that SLF mediates a migratory or a chemotactic signal for c-Kit-expressing stem cells (melanocyte precursors and primordial germ cells). By targeting expression of SLF to epidermal keratinocytes in mice, we observed extended distribution of melanocytes in a number of sites including oral epithelium and footpads where neither melanocytes nor their precursors are normally detected. In addition, enlarged pigmented spots of KitW and other spotting mutant mice were observed in the presence of the SLF transgene. These results provide direct evidence that SLF stimulates migration of melanocytes in vivo. We also present data suggesting that SLF does not simply support survival and proliferation of melanocytes but also promotes differentiation of these cells. Unexpectedly, melanocyte stem cells independent of the c-Kit signal were maintained in the skin of the SLF transgenic mice. After the elimination of c-Kit-dependent melanoblasts by function-blocking anti-c-Kit antibody, these stem cells continued to proliferate and differentiate into mature melanocytes. These melanoblasts are able to migrate to cover most of the epidermis after several months. The SLF transgenic mice described in this report will be useful in the study of melanocyte biology.

Animals↗
PubMed1997

Differentiation of cultured neuroblastoma induced by staurosporine and cyclic AMP: methods for assessing a neuronal phenotype.

In cultured neuronal cells, neurite outgrowth provides a prominent morphological marker for assessing neurotrophic activity derived from different sources. Permanent cell lines are often used for such studies; however, the process of differentiation should be evaluated biochemically or electrophysiologically to determine whether the affected cells acquire a neuronal phenotype. We have reported that low-dose staurosporine acts synergistically with cyclic AMP to induce neuronal differentiation in a human neuroblastoma cell line. This protocol describes a method for examining phenotypic changes in cultured cells.

Cell Differentiation↗
PubMed1996

Decrease in neuron-restrictive silencer factor (NRSF) mRNA levels during differentiation of cultured neuroblastoma cells.

Non-neuronal cells and undifferentiated neuronal progenitors express the neuron-restrictive silencer factor (NRSF), a silencer protein which represses neuronal gene transcription in these cell types. Neuroblastoma, a childhood tumor of neuroectodermal origin, shares some biological properties with neuronal progenitor cells and can acquire neuronal phenotypes in response to a variety of agents, including cyclic AMP and staurosporine. We report here that NRSF mRNA content was markedly decreased in a human neuroblastoma cell line following differentiation induced by staurosporine plus cyclic AMP, with a concomitant increase in mRNA levels of synapsin I, whose expression is restricted to neuronal cell types. Our novel finding suggests that NRSF expression is related to an undifferentiated state and regarded as a biochemical marker of neuronal differentiation in neuroblastoma cells.

Actins↗
PubMed1996

Almost simultaneous measurement of cardiovascular and gas exchange variables during maximal exercise.

We measured gas exchange variables such as oxygen uptake, carbon dioxide output, and lung diffusing capacity using noninvasive techniques almost simultaneous with assessment of cardiovascular variables such as pulmonary blood flow at several levels of treadmill exercise up to and including maximal capacity. We utilized a single breath exhalation technique for measurement of diffusing capacity and cardiac output and breath by breath methodology for evaluating oxygen uptake. The equipment required for these measurements--rapid gas analyzers, oximeters, on-line computation, and pneumatic valves--are well within the capabilities of many exercise laboratories and are not difficult to use with subjects even at the heaviest levels of exercise. The results agreed well with values reported in the literature. From these entirely noninvasive measures, we calculated mixed venous oxygen saturation and maximal tissue oxygen diffusing capacity.

Adult↗
PubMed1996

The Gly40Ser mutation in the human glucagon receptor gene associated with NIDDM results in a receptor with reduced sensitivity to glucagon.

The pancreatic islet hormone, glucagon, stimulates hepatic glucose production and has also been shown to potentiate glucose-induced insulin secretion. Because glucagon is a key regulator of glucose homeostasis, its receptor, which mediates the actions of glucagon, was considered a candidate gene involved in the pathogenesis of NIDDM. We have previously reported that a single heterozygous missense mutation in exon 2 of the glucagon receptor gene, which changes a glycine to a serine (Gly40Ser), is associated with NIDDM in a French population. In the present study, the signaling properties of this mutant receptor were examined in baby hamster kidney cells and rat insulinoma cells (RIN-5AH) stably transfected with either the wild type or Gly40Ser mutant human glucagon receptor cDNAs. Competition assays using (125)I-labeled glucagon were performed, and in both cell types, the Gly40Ser mutant receptor was found to bind glucagon with an approximately threefold lower affinity compared with the wild type receptor. In both cell types, the production of cAMP in response to glucagon was decreased in cells expressing the mutant receptor compared with those expressing the wild type. Finally, glucagon-stimulated insulin secretion by RIN cells expressing the mutant receptor was decreased such that the dose-response curve was shifted to the right in comparison to that obtained with cells expressing the wild type receptor. These results indicate that this single-point mutation located in the extracellular region of the glucagon receptor decreases the sensitivity of target tissues to glucagon.

Amino Acid Sequence↗