Biomedical subjects

K Nishida

Publications and source records attributed to K Nishida.

At least 307 records · Page 17Linked to original sources

PubMed1994

Artificial endocrine pancreas and optimal blood glucose regulation in diabetic patients--from bedside-type to wearable-type.

The artificial endocrine pancreas is a feedback control system regulating insulin delivery on a minute-by-minute basis according to the measured blood glucose levels. The bedside-type artificial endocrine pancreas has been proven to be useful not only as a therapeutic tool for diabetes mellitus but also as an elegant research tool for investigating the pathophysiology of the disease. With significant advances in the development of a subcutaneous tissue glucose monitoring system, the wearable-type artificial endocrine pancreas has been applied to diabetic patients. With this system, perfect glycemic control can be obtained for longer periods in ambulatory diabetic patients. The trend in the development of the artificial endocrine pancreas is now directed to implantable devices. Much efforts have been conducted to realize these devices.

Blood Glucose↗

PubMed1994

Cystic radio-lucency of carpal bones in haemodialysis patients. An early indicator of the onset of carpal tunnel syndrome.

Patients receiving haemodialysis for more than 10 years were selected for this study in order to clarify an apparent sequential association of cystic lesions of carpal bones and carpal tunnel syndrome. X-rays and computed tomographs of 138 hands of 69 patients revealed cystic radiolucency of carpal bones in 35% of the hands. Radiographs were classified into three groups: Group A--cyst growing, Group B--cyst not growing, and Group C--cyst absent. The prevalence of carpal tunnel syndrome was 100% (27/27) in Group A, 5.6% (1/18) in Group B, and 6.5% (6/93) in Group C. Growth of the cyst precedes the development of carpal tunnel syndrome by about 2 or 3 years. Growth of the bone cyst indicates that inflammation had already extended to the tenosynovium and median nerve. Cystic radio-lucency of the carpal bones appears to be a useful indicator of the onset of carpal tunnel syndrome.

Adult↗

PubMed1994

Cubital tunnel syndrome in a patient in long-term haemodialysis.

The onset mechanism of cubital tunnel syndrome and carpal tunnel syndrome may be similar in haemodialysis patients. Carpal tunnel syndrome is well recognized as a consequence of dialysis-associated amyloidosis. This case report documents the development of cubital tunnel syndrome in a patient on haemodialysis treatment for 10 years. Proliferating granulation tissue at the elbow had entrapped and displaced the ulnar nerve. This was corrected surgically, and the patient experienced immediate relief of the numbness and the "tingling", but the muscular atrophy had not improved after 8 months.

Humans↗

PubMed1994

Progressive decreases in coronary vein flow during reperfusion in acute myocardial infarction: clinical documentation of the no reflow phenomenon after successful thrombolysis.

OBJECTIVES: This study was undertaken to examine the effects of coronary flow dynamics after thrombolysis on infarct size limitation. BACKGROUND: It has been commonly accepted that early thrombolysis does not necessarily salvage infarcted myocardium. Plausible causes for myocardial necrosis include such factors as elapsed time to reperfusion, residual stenosis, collateral vessels, hemodynamic loads, preconditioning and reperfusion injury. Recently, the no reflow phenomenon has been elucidated to be associated with infarct extension in clinical studies employing contrast echocardiography or thallium scintigraphy. METHODS: Nineteen patients with early reperfusion in acute anterior myocardial infarction and comparable clinical background were studied. The patients were classified into two groups on the basis of pattern of thermodilution measurements of great cardiac vein flow after reperfusion: group A, 9 patients with a progressive decrease in great cardiac vein flow during the 1st 24 h of the onset of infarction; and group B, 10 patients without this observation. Left ventricular ejection fraction and thallium perfusion defect were compared between the two groups at follow-up. RESULTS: There were no significant differences in systemic hemodynamic variables between groups A and B, and neither group had recurrent ischemic events suggesting reocclusion or restenosis during the study. In group A, both great cardiac vein flow (mean +/- SD 44 +/- 17% reduction) and oxygen extraction (38 +/- 15% reduction) were progressively decreased after the onset of reperfusion. Compared with group B, this group showed a lower left ventricular ejection fraction (36 +/- 7% vs. 63 +/- 15%, p < 0.01) and a larger thallium-201 defect severity index (1,091 +/- 366 U vs. 247 +/- 261 U, p < 0.01) at follow-up. Although other patient characteristics were comparable between the two groups, antecedent angina occurred in 90% of group B patients in contrast to only 33% of group A patients. CONCLUSIONS: Salvage of myocardium from infarction by successful thrombolysis was not observed in the patients demonstrating progressive decreases in great cardiac vein flow (group A). In those patients, inadequate myocardial reperfusion on a microvascular basis might be associated with a much larger myocardial infarction. Antecedent angina may protect against a progressive decrease in coronary flow and may have beneficial effects on infarct size limitation.

Adult↗

PubMed1994

Pharmacokinetic analysis of in vivo metabolism of amino acid or dipeptide conjugates of salicylic acid in rabbit intestinal microorganisms.

We analyzed the pharmacokinetics of salicylic acid (SA)-amino acid (alanine, glutamic acid, methionine, and tyrosine) or SA-dipeptide (glycylglycine) conjugates in rabbits, by using a model that takes into account the metabolism of prodrug to SA by intestinal microorganisms and, also, by model-independent analysis. The blood concentration profiles of these prodrugs and released SA following intracecal and oral administration to rabbits were obtained previously (Nakamura et al., J. Pharm. Pharmacol., 44, 295-299, 1992; Chem. Pharm. Bull., 40, 2164-2168, 1992; Int. J. Pharm., 87, 59-66, 1992; J. Pharm. Pharmacol., 44, 713-716, 1992). First, the overall in vivo behavior was evaluated by statistical moment analysis. Next, the blood concentration profiles of prodrug and SA following intracecal and oral administration were simultaneously fitted to the above model. In general, good agreement was observed between fitted lines and experimental data for every prodrug, suggesting the validity of this model. The obtained parameters characterized the difference in the rate of metabolism and absorption among the prodrugs. Lower absorbability and enhanced hydrolysis rate of the prodrug lead to prolonged blood concentration of SA.

Administration, Oral↗

PubMed1994

Determination of plasma tissue factor antigen and its clinical significance.

To investigate the clinical significance of determination of plasma tissue factor (TF) antigen, we have developed a highly sensitive enzyme-linked immunosorbent assay (ELISA) for plasma TF, using two different monoclonal antibodies against TF apoprotein, 6B4 (catching antibody) and 5G9 (detecting antibody), and tetramethyl benzidine/H2O2 as substrates. Titration curves of recombinant human TF in buffer containing Triton X-100 were linear within the range from 50 to 2000 pg/ml. The total assay time was 3 h. Ultracentrifugation and immunoblot analysis indicated that human plasma and urine contained 50,000 g sedimentable and non-sedimentable forms of TF, both of which were detected by our ELISA method. Plasma and urine concentrations of TF in healthy subjects and patients with various diseases were measured by the ELISA method. In healthy subjects, plasma and urinary TF levels were found to be 149 +/- 72 pg/ml (n = 30) and 175 +/- 60 pg TF/urine creatinine mg (n = 95), respectively. TF was increased in plasma of patients with disseminated intravascular coagulation (DIC), thrombotic thrombocytopenic purpura, vasculitis associated with collagen diseases, diabetic microangiopathy and chronic renal failure receiving haemodialysis, but not in the plasma of endotoxaemic patients without DIC. The plasma TF/serum creatinine ratio did not show a positive correlation. Measurement of TF antigen in plasma may be useful for evaluating the endothelial damage and cell destruction in TF-containing tissues.

Adult↗

PubMed1994

Absorption of organic anions as model drugs following application to rat liver surface in-vivo.

Absorption of organic anions (phenol red, bromphenol blue and bromosulphonphthalein) has been studied after their application to rat liver surface in-vivo, employing a cylindrical glass cell (i.d. 9 mm, area 0.64 cm2). Each drug appeared gradually in the blood with the peak level at about 1 h, after which its concentration declined slowly. Absorbed model drug was efficiently excreted into the bile. These observations appear to indicate the possibility of drug absorption from liver surface membrane. Absorption of model drugs was estimated to be more than 59% in 6 h. The biliary recovery and metabolism of phenol red did not change as compared with that after intravenous administration.

Administration, Topical↗

PubMed1994

Effect of preservatives on systemic delivery of insulin by ocular instillation in rabbits.

The effects of absorption promoters and ophthalmic preservatives on the systemic absorption of insulin through the ocular route were investigated in albino rabbits. Insulin absorption was evaluated by its hypoglycaemic response. Although ocular instillation of insulin alone did not decrease the serum glucose concentration, instillation of insulin with absorption promoters such as EDTA and saponin decreased it. The promoting effect depended on the concentration of the absorption promoters. Of ophthalmic preservatives investigated (benzalkonium chloride, paraben, 2-phenylethanol, benzyl alcohol and sorbic acid), benzalkonium, chloride and paraben showed promoting effects. The promoting effect for benzalkonium chloride was reversible and dependent on concentration of both benzalkonium chloride and insulin in the formulation.

Absorption↗

PubMed1994

Porphyromonas gingivalis fimbriae stimulate bone resorption in vitro.

Our previous study demonstrated that Porphyromonas gingivalis fimbriae induce the expression of interleukin-1, a potent bone-resorbing cytokine, in macrophages. This demonstration suggested to use the possibility that the fimbriae may stimulate bone resorption via the generation of an inflammatory cytokine(s). The present study was performed to test this suggestion. The bone-resorbing activity was evaluated by measuring the area of resorption lacunae on bone slices incubated with calvarial bone cells taken from 14-day-old mouse embryos. Fimbriae at 0.5 micrograms of protein per ml stimulated the bone-resorbing activity significantly, and the effect was dose and treatment time dependent. Since it is well known that interleukin-1 and granulocyte macrophage colony-stimulating factor induce differentiation of osteoclast lineage cells, we examined the involvement of these cytokines in fimbria-stimulated bone resorption. Fimbria-stimulated bone resorption was abolished significantly by antisera against both cytokines. We observed by Northern (RNA) blot assay that both cytokine genes were markedly expressed in the fimbria-treated calvarial bone cells. Our present data demonstrate that P. gingivalis fimbriae stimulate bone resorption in vitro.

Animals↗

PubMed1994

Primary leiomyosarcoma of the ureter.

Malignant tumors of the ureteral smooth muscle are rare and the prognosis is not clear. This is a report of a patient with primary leiomyosarcoma of the ureter surviving 9 years and 9 months postoperatively without any evidence of recurrence. Malignancy of the ureter was suspected on the basis of angiography and radical nephro-ureterectomy was performed without positive cytology results.

Adult↗

PubMed1994

Development of a miniaturized glucose monitoring system by combining a needle-type glucose sensor with microdialysis sampling method. Long-term subcutaneous tissue glucose monitoring in ambulatory diabetic patients.

OBJECTIVE: To develop a reliable and practical glucose monitoring system by combining a needle-type glucose sensor with a microdialysis sampling technique for long-term subcutaneous tissue glucose measurements. RESEARCH DESIGN AND METHODS: A microdialysis Cuprophan hollow-fiber probe (inner diameter, 0.20 mm; length, 15 mm) was perfused with isotonic saline solution (120 microliters/h) and glucose concentrations in the dialysate were measured by a needle-type glucose sensor extracorporeally. This system was tested both in vitro and in vivo. Subcutaneous tissue glucose concentrations were then monitored continuously in 5 healthy and 8 diabetic volunteers for 7 to 8 days. A hollow-fiber probe was inserted into the abdominal subcutaneous tissue. RESULTS: This monitoring system achieved excellent results in vitro. Subcutaneous tissue glucose concentrations were measured in a wide range from 1.7 to > 27.8 mM glucose, with a time delay of 6.9 +/- 1.2 min associated with a rise in glucose and 8.8 +/- 1.6 min with a fall in the glucose level (means +/- SE). The overall correlation between subcutaneous tissue (Y) and blood (X) glucose concentration was Y = 1.08X + 0.19 (r = 0.99). The subcutaneous tissue glucose concentration could be monitored precisely for 4 days without any in vivo calibrations and for 7 days by introducing in vivo calibrations. CONCLUSIONS: Glycemic excursions could be monitored precisely in the subcutaneous tissue by this microdialysis sampling method with a needle-type glucose sensor in ambulatory diabetic patients.

Adult↗

PubMed1994

[An evaluation of "now" (Japanese ima) in the process of cognition and solution of contradictory situations].

This study examines the relationship between the process of cognition and solution in contradictory situations and evaluation of the span comprehended by "now" (Japanese ima) in it. Eighty-eight subjects were asked to express the span of "now" in each of 24 contradictory situations, selected for and graded according to degree of both contradictoriness and solvability. The subjects expressed their evaluation on a bi-directional cline, comprising 21 time categories: in this cline, "now" is positioned in the center, and the categories of second, minute, hour, day, week, year, generation, century, and infinity to both the left for the past and the right for the future. Three coordinates emerged from the data, applying Dual Scaling. The first indicated that future-oriented solutions in contradictory situations generate wider spans of "now" than did past ones, the second that negative solutions to contradictions generate a less realistic interrelation between its self and his outside world than did positive ones, and the third that the cognitive process and that by which contradictory situations are solved contain a third dimension, different from both a past-future dimension and a positive-negative dimension.

Adult↗

PubMed1994

[In vitro synergistic effects of tazobactam/piperacillin with various antibiotics].

We investigated in vitro synergistic effects of tazobactam/piperacillin (TAZ/PIPC), a combination drug of tazobactam (TAZ) and piperacillin (PIPC) in the ratio of 1:4, with several other antibiotics against Pseudomonas aeruginosa, Serratia marcescens and methicillin-resistant Staphylococcus aureus (MRSA). Synergistic effects of TAZ/PIPC with each of tobramycin (TOB), netilmicin (NTL), fosfomycin (FOM), ciprofloxacin, minocycline or cefoperazone were observed against all bacteria tested in the checkerboard dilution method. No antagonistic effect was observed in combination of TAZ/PIPC with other antibiotics. Against P. aeruginosa, a combination of TAZ/PIPC with NTL was the most effective, with an average fractional inhibitory concentration (FIC) index of 0.459. And a combination of TAZ/PIPC with FOM was the most the effective against S. marcescens and MRSA. TAZ/PIPC combined with TOB or FOM showed bactericidal effect against P. aeruginosa No. 11, S. marcescens No. 39 and S. aureus O-62 at concentrations of the drugs that showed only bacteriostatic activity individually. Phase-contrast micrographic observations of P. aeruginosa No. 11 and S. marcescens No. 39 demonstrated that the bacterial cells treated with TAZ/PIPC were in filamentous forms and those treated with TOB or FOM were nearly normal. The combination of TAZ/PIPC with TOB or FOM induced filamentous cells with spheroplast-like structures and lysis. Those results suggest that the combination of TAZ/PIPC with aminoglycosides or FOM were useful in the treatment of infections by P. aeruginosa, S. marcescens and MRSA, especially those caused by beta-lactamase-producing strains.

Drug Synergism↗

PubMed1994

Giant cell tumor of bone: analysis of proliferative cells by double-labeling immunohistochemistry with anti-proliferating cell nuclear antigen antibody and culture procedure.

Giant cell tumor of bone (GCT) consists of multinucleated giant cells, fibroblast-like cells, and macrophage-like cells, but what constitutes the principal neoplastic cells and their histogenesis remains controversial. Proliferating cells in GCT have been immunophenotypically characterized with the cell cycle-related antigen proliferating cell nuclear antigen (PCNA). In seven cases, PCNA monoclonal antibody was applied by double-labeling immunohistochemical methods together with other cell-specific monoclonal antibodies. Many proliferating PCNA-positive cells were found in the vimentin-positive fibroblast-like cells, while almost all macrophage-like cells were negative for PCNA. The study of cultured cells showed that the fibroblast-like spindle-shaped cells were a neoplastic element. In addition, osteoclast-like cells were detected in co-culture systems of cells cultured from GCT with spleen cells. These studies support the concept that GCT is seen as a neoplasm of fibroblast-like cells with a strong reactive infiltration of cells from the mononuclear phagocyte system.

Antibodies, Monoclonal↗

PubMed1994

[Age-related alteration of tear dynamics in normal volunteers].

Age-related alteration of tear dynamics was studied using a newly developed fluorophotometer. The subjects, 55 eyes of 30 normal volunteers, included 32 eyes of 16 younger subjects in their twenties and 23 eyes of 14 older subjects aged 50 years and above. After instillation of 1 microliter of fluorescein solution at a concentration of 50 micrograms/ml into the temporal bulbar conjunctiva, fluorescence intensity was measured with the fluorophotometer every minute for 10 minutes after instillation. Fluorescein concentration was calculated from the intensity, and various parameters of tear dynamics were analyzed. In the younger subjects, the tear volume, initial turnover rate and basal turnover rate were 10.6 +/- 6.0 microliters, 37. 1 +/- 15.6%/min, and 25.8 +/- 15.2%/min, respectively. In the older subjects, these values were 6.5 +/- 2.6 microliters, 26.5 +/- 11.4%/min, and 20.5 +/- 13.5%/min, respectively. The basic tear flow rate, calculated from the basal turnover rate and tear volume, was 2.7 +/- 2.2 microliters/min in the younger and 1.4 +/- 1.0 microliter/min in the older subjects. There was a statistically significant difference in the tear volume, tear turnover rate, and basic tear flow rate between the younger and older subjects.

Adult↗

PubMed1994

Immunohistochemical localization of transforming growth factor-beta 1, -beta 2, and -beta 3 latency-associated peptide in human cornea.

PURPOSE: To study spatial distribution of TGF-beta isoforms (TGF-beta 1, -beta 2, and -beta 3) in the human cornea and to elucidate their biologic roles in corneal maintenance. METHODS: Frozen sections obtained from eight human autopsy eyes were placed on gelatin-coated slides. After blocking of nonspecific binding sites, the slides were incubated with rabbit polyclonal antibody to the latency-associated peptide (LAP) region of human TGF-beta 1, TGF-beta 2, and TGF-beta 3 precursors, followed by the incubation with biotinylated swine anti-rabbit IgG. Subsequently, a streptavidin-labeled alkaline phosphatase technique was used. RESULTS: In the corneal region, beta 1-LAP antibody did not stain either epithelium or stroma, beta 2-LAP antibody stained all epithelial cell layers and the corneal stroma, and beta 3-LAP antibody stained the subepithelial region alone. The staining pattern in the limbal region was almost the same as in the corneal region, except in the limbal stroma, which was stained with beta 1-LAP antibody in three of eight samples. In the trabecular meshwork, all samples showed clear staining with beta 2-LAP antibody, whereas beta 1-LAP and beta 2-LAP antibody stained faintly in five of eight and four of eight samples, respectively. CONCLUSION: beta 2-LAP was found in the corneal epithelium and stroma and beta 3-LAP in the subepithelial region, suggesting that TGF-beta 2 and TGF-beta 3 may play essential roles in normal corneal epithelial maintenance in vivo.

Adult↗

PubMed1994

[Translocation t(11;14) (q13;q32) in six patients with lymphoid malignancies of mature B-cell phenotype].

We described six patients with t(11;14)(q13;q32) in lymphoid malignancies. Based on the histologic or morphologic findings of these patients, malignant lymphoma diffuse large cell (ML-DL) was diagnosed in two patients, small lymphocytic (SL) in one, mantle zone lymphoma (MZL) in one, prolymphocytic leukemia (PLL) in one, and chronic lymphocytic leukemia with > 10% prolymphocytes (CLL/PL) in one. Three cases showed involvement of the gastro-intestinal tract, and four were leukemic. Five cases were dead 12 to 25 months after the time of chromosomal analysis. Immunological studies revealed that all the patients were positive for CD5, CD20, HLA-DR, and only one was weak positive for CD10. Using probe b, SstI-Sst I segment, Southern blot analysis showed the rearrangement of BCL-1 gene in a patient with MZL. Our results suggested that t(11;14) is found in lymphoid malignancies with mature B-cell phenotype and that hepatosplenomegaly, gastrointestinal involvement, leukemic manifestation, and poor prognosis are common clinical features.

Aged↗

PubMed1993

N-acetyl-D-galactosamine inhibits TNF-alpha gene expression induced in mouse peritoneal macrophages by fimbriae of Porphyromonas (Bacteroides) gingivalis, an oral anaerobe.

Adherence to host cells is an essential step in the initiation of most infectious diseases. It is well known that bacterial fimbriae may be involved in the adherence. Porphyromonas (Bacteroides) gingivalis is a pathogenic organism of adult periodontitis which is a chronic inflammatory disease. Using an experimental system for fimbria-induced TNF-alpha gene expression in mouse peritoneal macrophages, we examined the role of sugar moieties in the adhesion of P. gingivalis fimbriae to these cells. The fimbriae strongly induced TNF-alpha gene expression in the macrophages, and marked TNF activity toward fibroblasts was observed in culture supernatants of the fimbria-treated cells. The potent expression of TNF-alpha was inhibited by N-acetyl-D-galactosamine, but not inhibited by D-mannose, alpha-lactose, and alpha-L-rhamnose, D-galactose, and N-acetyl-D-glucosamine.

Acetylgalactosamine↗