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K Nishida

Publications and source records attributed to K Nishida.

At least 289 records · Page 16Linked to original sources
PubMed1995

Ocular permeability of FITC-dextran with absorption promoter for ocular delivery of peptide drug.

The purpose of this study is to characterize an ocular permeability of FITC-dextran, as a model of peptide drug, and to evaluate the effects of absorption promoters on the ocular permeability of FITC-dextran. The in vitro penetrations of FITC-dextrans (average molecular weight 4400 and 9400: FD-4 and FD-10) were measured across the isolated corneal and conjunctival membranes of albino rabbits using a two-chamber glass diffusion cell. The corneal permeabilities of FD-4 and FD-10 were much lower than the conjunctival permeabilities. Scraping of corneal epithelium extremely increased the corneal permeabilities. The penetration parameters were estimated according to Fick's equation. Absorption promoters such as EDTA, taurocholic acid, benzalkonium chloride and saponin significantly increased corneal permeabilities of FD-4 and FD-10. Saponin showed the highest promoting activity. Conjunctival permeabilities of FD-4 and FD-10 were also enhanced by absorption promoters although the improvements of conjunctival permeabilities by absorption promoters were smaller than those of corneal permeabilities. Ratios of corneal to conjunctival permeabilities were enhanced by absorption promoters. These results indicate that an ocular delivery of instilled hydrophilic macromolecule is markedly low and a selective use of absorption promoter can improve the extent and pathway of its ocular absorption.

Absorption↗
PubMed1995

[A case of Lemmel's syndrome caused by a large diverticular enterolith at the peripapillary portion of the duodenum].

A 93-year-old woman admitted because of epigastralgia. Cholelithiasis, obstructive jaundice, acute suppurative cholangitis and acute pancreatitis were diagnosed on blood chemistry and ultrasonography on admission. We performed emergency PTCD. A calculus 4 cm in diameter was detected at the papilla of Vater and marked dilatation of the common bile duct and pancreatic duct. ESWL was performed because of her age and because endoscopical operation seemed to be difficult. After lithotripsy, PTC and endoscopy demonstrated a diverticulum at the peripapillary portion of the duodenum. Based on analysis of PTC result before and after ESWL, we diagnosed this case as Lemmel's syndrome (obstructive jaundice, acute suppurative cholangitis and acute pancreatitis) caused by a large diverticular enterolith at the peripapillary portion of the duodenum. ESWL treatment of aged patient with an enterolith is safe.

Acute Disease↗
PubMed1995

Effects of tazobactam on the frequency of the emergence of resistant strains from Enterobacter cloacae, Citrobacter freundii, and Proteus vulgaris (beta-lactamase derepressed mutants).

When Enterobacter cloacae, Citrobacter freundii, and Proteus vulgaris were treated with piperacillin (PIPC) in combination with tazobactam (TAZ), the in vitro frequency of emergence of resistant strains (beta-lactamase producing mutants) was lower than with PIPC or ceftazidime (CAZ) treated bacteria. In a mouse intraperitoneal infection model caused by E. cloacae, beta-lactamase derepressed mutants were detected following therapy with PIPC or CAZ, although no derepressed mutants were detected after treatment with PIPC in combination with TAZ. This suppression of the selection of derepressed mutants, which produce large amounts of beta-lactamases, by the combination of TAZ and PIPC suggests that the combination delays the increase of resistant mutants compared with PIPC alone.

Animals↗
PubMed1995

Development of a ferrocene-mediated needle-type glucose sensor covered with newly designed biocompatible membrane, 2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate.

To prepare the long-life and stable glucose sensor, we developed the ferrocene-mediated needle-type glucose sensor covered with newly designed biocompatible membrane, 2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate (MPC-co-BMA) membrane. In this membrane, the hydrophilic phosphorylcholine chains were grafted on the hydrophobic polymer surface. 1. The poly(MPC-co-BMA) membrane inhibited platelet activation and protein adhesion on the surface, showing excellent biocompatibility. These results suggested that the hydrophilic phospholipids chains might have the potential for suppressing activation and adsorption of biochemical molecules. 2. The ferrocene-mediated needle-type glucose sensor covered with poly(MPC-co-BMA) membrane achieved excellent results in vitro. Subcutaneous tissue glucose concentrations were measured in a wide range from 1.7 to more than 16.7 mmol/l. The correlation between subcutaneous tissue (Y) and blood (X) glucose concentrations was Y = 1.04X + 0.12 (r = 0.98). The subcutaneous tissue glucose concentrations could be monitored precisely for 7 days without any in vivo calibrations, and for 14 days by introducing in vivo calibrations. We therefore conclude that this sensor is stable and reliable, as compared to any other glucose sensors we developed.

Adult↗
PubMed1995

[Quantitative evaluation of corneal epithelial barrier function in corneal epithelial edema].

Corneal epithelial barrier function in patients with corneal epithelial edema was evaluated by fluorophotometry. Fluorescein uptake through the intact corneal epithelium was 28.1 +/- 2.7 ng/ml (n = 35, mean +/- SE (standard error), calculated from the standard line) at 30 minutes after instillation of 3 microliters of 0.5% sodium fluorescein (20 minutes after eye washing with 20 ml of BSS PLUS). Fluorescein uptake by the cornea in 7 patients with corneal epithelial edema and 6 patients with corneal stromal edema without epithelial edema were 2,489.7 +/- 1,045.6 ng/ml and 99.3 +/- 25.0 ng/ml, respectively, showing a significant increase when compared to normal corneal epithelium (p < 0.0005). Moreover, in patients with corneal epithelial edema, the corneal epithelial barrier function showed significant decrease in comparison with those having corneal stromal edema without epithelial edema (p < 0.05). These results demonstrate a significant decrease in the corneal epithelial barrier function in the epithelial edema.

Cornea↗
PubMed1995

Antitumor effects of liposomes containing adriamycin on chemically-induced rat malignant fibrous histiocytoma.

Malignant fibrous histiocytoma (MFH) is the most common soft tissue sarcoma. No effective chemotherapeutic agents, however, have been reported. Here we report our evaluation of the antitumor effects of liposomes containing adriamycin (LADM) against chemically-induced rat MFH. Either free adriamycin (ADM) or LADM was administered at dosages of 4.0, 8.0 or 12.0 mg/kg by intravenous injection. The tumor responded to LADM with prolonged growth delay, but equivalent doses of free ADM were less effective. Additionally, LADM prolonged the life span of rats longer than did free ADM. Also, the body weight loss was less with LADM than with equivalent doses of free ADM. In tissue distribution studies, we observed that the ADM level in the blood and in the tumor with LADM remained higher than with free ADM. These results indicate that liposomes alter in vivo ADM tissue distribution and increase antitumor activity against rat MFH with reduced toxic side effects.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1995

Detection of four different 11q23 chromosomal abnormalities by multiplex-PCR and fluorescence-based automatic DNA-fragment analysis.

A nested polymerase chain reaction (PCR) protocol was developed for rapid detection of four different 11q23 abnormalities by a single PCR assay. During each of the two PCR rounds a sense primer located within exon 5 of the MLL gene at 11q23 was combined with four different antisense primers, each located within possible translocation partner genes at chromosomes 4, 6, 9, and 19, respectively. Except for the MLL primer all primers used during the second round of nested-PCR carried a characteristic fluorescence label at their 5'-end. Agarose gel analysis of the PCR products was sufficient to discriminate between the absence of any of the four MLL rearrangements and the presence of at least one of them. Discrimination of the four different MLL translocation partner genes was not possible by agarose gel analysis due to a molecular heterogeneity of the 11q23 breakpoints resulting in PCR products of variable size. For this reason, automatic fluorescence-based DNA-fragment analysis was used to exactly define the MLL translocation partner genes if a positive result had been obtained by agarose gel analysis. In patients with leukemia, this assay may enable a fast and highly sensitive detection of different 11q23 abnormalities, which usually correlate with poor clinical prognosis.

Base Sequence↗
PubMed1994

Nonrandom chromosomal rearrangements of 14q32.3 and 19p13.3 and preferential deletion of 1p in 21 patients with multiple myeloma and plasma cell leukemia.

Structural chromosomal abnormalities and their break-points were characterized in 17 patients with multiple myeloma (MM) and 4 with plasma cell leukemia by banding. Chromosome 14q32 translocations with a variety of partners were detected in 13 patients, and a variant translocation t(8;22)(q24.1;q11) was detected in 1. Three recurrent 14q32 translocations have been identified: t(6;14)(p21.1;q32.3) occurring in 3 cases, and t(11;14)(q13;q32.3) and t(14;18) (q32.3;q21.3) each occurring in 2 cases. Translocations t(1;14)(q21;q32.3), t(3;14)(p11;q32),t(7;14)(q11.2;q32.3), and t(11;14)(q23;q32.3) were found in each patient, whereas in the remaining 2 patients, partner chromosomes could not be determined. The band 19p13.3 was newly delineated as a recurrent breakpoint involved in translocations in MM. Chromosomes 1 and 6 were also commonly involved in structural abnormalities (14 and 10 patients, respectively), although no particular bands were noted. However, the short arm of chromosome 1 was preferentially involved in deletion, suggesting a certain antioncogene on 1p associated with the development of myeloma. In addition; fluorescence in situ hybridization was successfully applied to determine the nature of the structural abnormalities in a patient with t(8;22) translocation. The present findings suggest that there may be subsets of 14q32 translocations specific to MM.

Adult↗
PubMed1994

Organization of the bovine gene encoding the endothelial nitric oxide synthase.

The bovine endothelial nitric oxide synthase gene plus 2.9 kilobases of 5'-flanking sequence has been isolated and characterized. The gene spans 20 kilobases and contains 26 exons and 25 introns. Two transcription start sites have been determined by primer extension analysis which are located 170 and 240 base pairs upstream, respectively, from the methionine translational initiation codon. Evidence supporting the upstream boundary region for transcriptional initiation was also obtained by reverse transcription-polymerase chain reaction. The 5'-flanking region lacks a typical TATA box but contains numerous putative transcription factor binding sites. These include consensus sequences for an AP-1 site, an NF-1 site, a tumor necrosis factor responsive element, two sterol regulatory elements, 3 acute-phase response element, two sterol regulatory elements, 3 acute-phase response elements, 6 GATA motifs, 16 CACCC boxes, 5 Sp1 sites, 15 estrogen half-palindromic motifs, and 9 fluid shear stress-responsive elements. The isolated gene promoter directs basal transcription of a luciferase reporter gene when transiently transfected into bovine aortic endothelial cells. High sequence homology of the promoter region to the human endothelial nitric oxide synthase gene promoter (75% nucleotide identity in 1.6 kilobases of 5'-flanking sequence) suggests evolutionary conservation of transcriptional regulation. Isolation and characterization of the bovine endothelial nitric oxide synthase gene should facilitate further investigation of mechanisms by which gene expression is regulated.

Amino Acid Oxidoreductases↗
PubMed1994

Detection of 14q32 translocations in B-cell malignancies by in situ hybridization with yeast artificial chromosome clones containing the human IgH gene locus.

Partner sites of 14q32 translocations found in B-cell malignancies were detected by fluorescence in situ hybridization (FISH) using yeast artificial chromosome (YAC) clones, Y20 and Y6, containing the human Ig heavy chain (IgH) gene locus. Y20 spans a 160-kb upstream and 40-kb downstream region of the JH segments on chromosome band 14q32.33. Y6 is 300-kb upstream of Y20, and spans a further 320-kb telomeric region. The human DNA sequences amplified by Alu polymerase chain reaction of the YAC clones were used as probes for FISH to study six patients with non-Hodgkin's lymphoma (NHL), one patient with acute lymphoblastic leukemia, and one cell line FR4 established from a plasmacytoma. Three telomeric YAC clones each specific for 3q, 8q, and 18q were also used to further characterize 14q32 translocations. The IgH YACs were successfully applied to detect cytogenetically invisible subtelomeric translocation of the IgH gene locus to each partner site in t(14;18), t(8;14), and t(14;19), and to identify t(3;14) (q27;q32.33) in three patients with 14q32 translocation of unknown origin. Furthermore, complex translocations involving more than three chromosomes were detected in an NHL patient with t(8;14), and t(3;12), and in the FR4 with der(14)t(8;14), der(8)dic(1;8), and del(1)(q21). The technique would be a useful tool in elucidating the mechanisms of a 14q32 translocation in B-cell malignancies.

Aged↗
PubMed1994

The point mutation Arg615-->Cys in the Ca2+ release channel of skeletal sarcoplasmic reticulum is responsible for hypersensitivity to caffeine and halothane in malignant hyperthermia.

Malignant hyperthermia (MH) is an autosomal dominant myopathy. Molecular genetic studies have shown that the alteration of Arg615 to Cys in the Ca2+ release channel of skeletal muscle sarcoplasmic reticulum (ryanodine receptor) is cosegregated with porcine MH (Fujii, J., Otsu, K., Zorzato, F., de Leon, S., Khanna, V. K., Weiler, J. E., O'Brien, P. J., and MacLennan, D. H. (1991) Science 253, 448-451; Otsu, K., Khanna, V. K., Archibald, A., and MacLennan, D. H. (1991) Genomics 11, 744-750). Here, using the fluorescence calcium indicator indo-1, we determined the concentration of ionized cytosolic calcium in myoblastic cells transfected with either the wild-type or mutated ryanodine receptor cDNA. The cells expressing the mutant ryanodine receptor showed higher sensitivity to caffeine, which induces Ca2+ release from the sarcoplasmic reticulum through the ryanodine receptor. Exposure to clinical doses of halothane resulted in a rapid increase of [Ca2+]i in cells expressing the mutated ryanodine receptor, whereas no [Ca2+] changes were observed in cells expressing the wild-type ryanodine receptor. These results provide definite evidence that a single amino acid mutation, Arg615-->Cys, in the ryanodine receptor is causative of MH.

Amino Acid Sequence↗
PubMed1994

Detection of herpes simplex virus DNA in human tear film by the polymerase chain reaction.

We investigated the use of the polymerase chain reaction for detecting genomes of herpes simplex virus, varicella-zoster virus, and cytomegalovirus from tear film of patients with clinically diagnosed herpes simplex virus keratitis. Using the polymerase chain reaction with a herpes simplex virus detection sensitivity adjusted to 1.0 plaque-forming units/ml, we detected herpes simplex virus genomic sequences in 12 of 12 epithelial keratitis specimens, two of six stromal keratitis specimens, but in none of 20 normal specimens. Neither varicella-zoster virus nor cytomegalovirus genomic sequences were detected in any sample. These results suggest that polymerase chain reaction quickly performed with reduced sensitivity is useful as a diagnostic tool for confirming clinical observations.

Base Sequence↗
PubMed1994

Intestinal permeability of ophthalmic beta-blockers for predicting ocular permeability.

The purpose of this study was to investigate the intestinal permeability of ophthalmic beta-blockers and evaluate the utility of intestinal membrane for predicting the ocular permeability. The penetrations of beta-blockers were measured across the isolated jejunum and colon of the albino rabbit using a two-chamber glass diffusion cell. beta-Blockers tested include atenolol, carteolol, tilisolol, timolol, and befunolol. Colonic membrane showed lower permeability of hydrophilic drugs than jejunal membrane. Scraping the entire cell monolayer of jejunum increased the drug permeability. There was a significant correlation between colonic permeability coefficients and lipophilicities of beta-blockers. The permeability coefficients through jejunum and scraped jejunum were not susceptible to drug lipophilicities. Jejunum, scraped jejunum, and colon showed permeability coefficients almost equal to those of sclera, conjunctiva, and cornea, respectively. There was a significant correlation between permeability coefficients through colon and cornea. These results indicate that the steady-state permeability of ophthalmic beta-blockers through ocular membranes may be predicted by measuring the permeability through certain intestinal membranes. However, the analyses of intestinal permeability using Fick's equation showed the functional difference of intestinal permeability from ocular permeability of ophthalmic beta-blockers.

Adrenergic beta-Antagonists↗
PubMed1994

Thyroid hormone enhances Ca2+ pumping activity of the cardiac sarcoplasmic reticulum by increasing Ca2+ ATPase and decreasing phospholamban expression.

Phospholamban is a putative suppressor of the Ca2+ ATPase of the cardiac sarcoplasmic reticulum. The level of mRNA encoding the Ca2+ ATPase has been shown to be increased, whereas the phospholamban mRNA level to be decreased in the ventricles obtained from hyperthyroid rabbits [Nagai R, Zarain-Herzberg A. Brandl CJ, Fujii J. Tada M. MacLennan DH, Alpert NR, Periasamy M. (1989) Proc Natl Acad Sci USA 86: 2966-2970]. The present study was designed to examine whether these effects of thyroid hormone on the expression of the Ca2+ ATPase and phospholamban are exerted directly on cardiac myocytes and whether the resultant incoordinate expression of these proteins alters Ca2+ pumping activity. We studied the levels of phospholamban and Ca2+ ATPase mRNA in primary isolated neonatal rat myocardial cells incubated with triiodothyronine (T3) for 3-48 h and the Ca2+ uptake activity of the microsomes prepared from the cells. Northern blot analysis showed that T3 decreased phospholamban mRNA levels to about a half of control in 24 h. On the other hand, Ca2+ ATPase mRNA gradually increased with time. EC50 for phospholamban mRNA expression was 2.5 x 10(-10) M which was approximately 10 times higher than that for the Ca2+ ATPase. T3 increased Vmax of Ca2+ uptake with the significant reduction of K0.5 for Ca2+ (0.40 +/- 0.02 microM for control v 0.31 +/- 0.02 microM for T3-treated vesicles), indicating that thyroid hormone stimulates Ca2+ pumping activity not only by increasing the Ca2+ ATPase but also decreasing phospholamban. These results suggested that phospholamban regulates the Ca2+ ATPase in dual modes; in short time range, by decreasing the affinity of the Ca2+ ATPase for Ca2+ by phosphorylation of phospholamban with cAMP-dependent protein kinase, and in long time range, by changing the molecular ratio between the two proteins through the regulation of gene expression.

Animals↗
PubMed1994

Rapid superoxide production by endothelial cells and their injury upon reperfusion.

Cultured human umbilical vein endothelial cells (EC) were exposed to hypoxia for various time periods followed by reoxygenation, and production of both O2- and H2O2 by EC was measured using the cytochrome c and scopoletin methods, respectively. Production of significant amounts of O2- was observed as early as 1 min after reoxygenation, reached maximum at 3 min and seemed to decline thereafter. Production of H2O2 was observed slightly later than that of O2-. Endothelial cell injury during hypoxia/reoxygenation was determined by both the trypan blue dye exclusion and chromium release methods. Significant increase of EC injury was detected after reoxygenation by both methods. This injury was significantly inhibited by allopurinol but not by superoxide dismutase or catalase. These results indicate that the production of reactive oxygen metabolites by EC and EC injury occur very rapidly after reoxygenation, which has not been reported, and these should be taken in consideration for the understanding and treatment of the clinical reperfusion injury.

Allopurinol↗
PubMed1994

Transesophageal echo-guided balloon dilatation for postoperative pulmonary venous obstruction.

Pulmonary venous obstruction (PVO), or stenosis, is still a major complication of postoperative total anomalous pulmonary venous return, being very complex in its pathogenesis. For some types of PVO, surgery is effective, but a reoperation under cardiopulmonary bypass is generally difficult and carries a high risk. The operative balloon dilatation method performed under the guidance of transesophageal echography and fluoroscopic monitering is simple as well as safe. We describe herein the technique involved in performing this procedure through the case of a 10-month-old boy.

Catheterization↗
PubMed1994

Effect of successful angioplasty following thrombolysis on infarct size and left ventricular function.

The role of the angioplasty following thrombolysis in acute myocardial infarction has been discussed in several studies, however the effect of successful angioplasty on infarct size and left ventricular function has not been properly evaluated. Successful reperfusion was achieved in 79 out of 104 patients with primary anterior acute myocardial infarction. These patients were classified as follows, according to the type of intervention during the acute phase: 50 patients in which thrombolysis was successful (the thrombolysis group); 12 patients who underwent successful immediate angioplasty following successful thrombolysis (the immediate angioplasty group); and 17 patients in which rescue angioplasty was successful (the rescue angioplasty group). The 25 patients whose infarct-related vessels were not reperfused after intervention were classified as the non-reperfused group. Infarct size, evaluated as defect volume by T1-201 SPECT, 1 month after the onset, was 840 +/- 154 units (mean +/- S.D.) in the immediate angioplasty group and was similar to that in the thrombolysis group (948 +/- 88 units), but significantly smaller than in the non-reperfused group (1759 +/- 108 units). There were no significant differences in left ventricular function in the immediate angioplasty group and the thrombolysis group. Successful rescue angioplasty did not have any beneficial effect on left ventricular functions or infarct size, when compared with the failed thrombolytic group (1105 +/- 169 units vs. 1617 +/- 169 units). End-diastolic volume (52 +/- 3 ml/m2) in the successful rescue angioplasty group, however, was significantly smaller than in the failed thrombolysis group (67 +/- 3 ml/m2).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗