Biomedical subjects

K Ono

Publications and source records attributed to K Ono.

At least 577 records · Page 32Linked to original sources

PubMed1994

The use of a human dura mater allograft for the repair of a contaminated abdominal wall defect: report of a case.

A case report of an infected full-thickness abdominal wall defect treated successfully with a human dura mater allograft is presented. A review of the literature and a discussion of prosthetic abdominal wall repair is also included. A 46-year-old woman presented with multiple small bowel perforations and a large abdominal wall defect due to a motor vehicle collision. A gamma-irradiated human dura mater prosthesis was used to repair the large abdominal wall defect which had been infected by a jejunal fistula. After more than 4 years of follow-up, the patient is free of complications, including wound infection, herniation, and ileus. The human dura mater allograft is thus considered to be a useful prosthesis for repairing potentially infected wounds.

Abdominal Muscles↗

PubMed1994

Simulation of car impact to pedestrian lower extremity: influence of different car-front shapes and dummy parameters on test results.

Sled impact tests on mechanical substitutes for a pedestrian were conducted as a preliminary study for the purpose of developing a subsystem test procedure for the assessment of car-front aggressiveness to pedestrian legs. Four mechanical substitutes for a pedestrian were used in the test: the leg of a rotationally symmetrical pedestrian dummy (RSPD) as the representation of a subsystem, a HYBRID-II pedestrian dummy, a modified HYBRID-II pedestrian dummy equipped with a steel bar serving as knee joint, and a RSPD - HYBRID-IIP combined dummy in which the lower part of the RSPD and the upper part of the HYBRID-IIP were connected by a joint in such a way that the movements of the upper part were similar to those in cadaver tests. In the tests the following were evaluated: (i) the influence of vehicle shape on knee response and on vehicle impact force; (ii) the influence of the upper body mass on knee response and on vehicle impact forces; (iii) the influence of the bumper system on knee response, the kinematics of pedestrian mechanical substitute, and on vehicle impact forces; (iv) the influence of pedestrian mechanical substitute characteristics on its kinematics and knee response, and on vehicle impact forces. This paper describes a primary concept when subsystem test methods for the assessment of car-front aggressiveness to pedestrian legs in a car-pedestrian collision are considered.

Acceleration↗

PubMed1994

Spongy metal Lübeck hip prostheses for osteoarthritis secondary to hip dysplasia. A 2-6-year follow-up study.

Between May 1987 and December 1990, 66 hips in 59 patients with osteoarthritis secondary to hip dysplasia underwent cementless total hip arthroplasty with a spongy metal Lübeck hip prosthesis (S+G Implants, Lübeck, Germany) that had a fully porous-surfaced short stem made of cased cobalt-chrome-molybdenum alloy. Sixty-five hips in 58 patients were prospectively followed for 2-6 years (mean, 43 months). Patient age at operation ranged from 29 to 63 years (mean, 51 years). The Merle d'Aubigné hip score improved from 7.8 before surgery to 16.9 at the final follow-up evaluation. All hips were rated as either excellent (63%) or good (37%). Mild thigh pain was recognized in only three hips (5%) at 6 months after surgery, but it disappeared within 2 years. Serial roentgenograms showed stable fixation with bone ingrowth in all hips, that is, bone densification in contact with the implant and trabecular connection to the endosteal surface. The authors found no migration of the implant or circumferential radiolucency. Moderate osteopenia, presumably due to stress shielding, was seen in only four hips (6%). Acetabular bone-grafting performed in 31 hips gave successful support to the socket. Cancellous bone chips grafted to small defects showed excellent remodeling. The authors conclude that the spongy metal Lübeck hip prosthesis contributed to lower rates of thigh pain and migration than cementless prostheses.

Adult↗

PubMed1994

N-CAM mutation inhibits tangential neuronal migration and is phenocopied by enzymatic removal of polysialic acid.

The mutation of N-CAM in mice produces a phenotype dominated by an undersized olfactory bulb and accumulation of precursors in the subependymal layer. We demonstrate here that this defect can be duplicated by injection of an enzyme that specifically destroys the polysialic acid (PSA) moiety associated with N-CAM. Studies of BrdU-labeled and pyknotic cells suggest that this defect reflects a decrease in the rostral migration of olfactory precursors and not a change in the proliferation or rate of death of these cells. In addition to their ectopic location, these cells had fewer growth cone-like processes oriented along the migration route. In contrast to tangential movement, radial migration of granule cells in the olfactory bulb was not affected by loss of PSA. These results support the proposed role for PSA in cell translocation, discriminate between different mechanisms of cell migration, and provide insight as to the nature of the N-CAM mutant phenotype.

Animals↗

PubMed1994

Determination of the target volume of HeLa cells treated with platinum-195 m radiolabeled cis-diammine(1, 1-cyclobutane-dicarboxylato)-platinum(II); comparison with cis- and trans-diamminedichloroplatinums(II).

HeLa S-3 cells were treated with 195mPt-radiolabeled cis-diammine(1, 1-cyclobutane-dicarboxylato)platinum(II) (carboplatin) under various conditions, and the relationship between lethal effect and the number of Pt atoms binding to DNA, RNA and proteins was examined. The mean lethal concentrations for the cells treated with carboplatin at 37 degrees C for 1, 2 and 3 h were 553.4, 194.3 and 68.7 microM, respectively. By using identically treated cells, the numbers of Pt-atoms combined with DNA, RNA and protein molecules were determined after fractionation of the cells. In this way the D0 values (D0, dose that would give an average of one lethal event per member of the population), expressed as the drug concentration, were substituted for the number of Pt atoms combined with each fraction. The target volumes, the efficiency of Pt atom to kill cells expressed as the reciprocals of the D0 values, were then calculated with each fraction. The results suggested that DNA was the primary target for cell killing by carboplatin. The target volumes for DNA were 0.891 x 10(4), 2.01 x 10(4) and 3.96 x 10(4) nucleotides for 1, 2 and 3 h treated cells, respectively. The cell killing effects of carboplatin were lower than those of cis-diamminedichloroplatinum(II) (CDDP) by factors of 6.0, 2.8 and 2.6 for 1, 2 and 3 h treatments at 37 degrees C, respectively, in terms of the target volume, while those in terms of the mean lethal dose (D0) were 59.5, 29.0 and 21.5, respectively.

Antineoplastic Agents↗

PubMed1994

FK506 inhibits renal glomerular thrombosis induced in rats by nephrotoxic serum and lipopolysaccharide.

We investigated the effect of the potent immunosuppressive agent, FK506, on experimental glomerular thrombosis in rats by combined injections of nephrotoxic serum (NTS) and lipopolysaccharide (LPS). Either FK506 or placebo was administered intramuscularly three hours prior to injection of NTS that was followed one hour later by LPS. Rats were killed five hours after the LPS injection. Compared with placebo, FK506 pretreatment significantly reduced thrombosis formation, in a dose-dependent manner. FK506 also reduced proteinuria and the rise of serum creatinine level. Early infiltration of polymorphonuclear leukocytes into the glomeruli after LPS injection was significantly suppressed in the FK506 group compared with the placebo group. We also measured serum tumor necrosis factor (TNF) activity by using an L929 fibroblast cytotoxicity assay. Peak serum TNF activity was observed one hour after LPS injection, and FK506 significantly suppressed the elevation. Thrombosis was also developed in athymic nude rats, suggesting thrombosis formation is T cell independent. These data suggest that the FK506 has inhibitory effects on non-lymphocytes and possesses an anti-inflammatory effect in vivo.

Acute Disease↗

PubMed1994

Effect of hyperthermia on the number of platinum atoms binding to DNA of HeLa cells treated with 195mPt-radiolabelled cis-diaminedichloroplatinum(II).

HeLa S-3 cells were treated with 195mPt-radiolabelled cis-diaminedichloroplatinum II) (CDDP) for 60 min at various temperatures to examine the relationship between the lethal effect and the number of Pt atoms binding to DNA, RNA and protein molecules. The mean lethal concentration (Do) of CDDP for 60-min treatment at 0, 25, 37, 40, 42 and 44 degrees C was 233, 69.9, 15.9, 11.7, 8.3 and 4.7 microM respectively. By using identically treated cells, the number of Pt atoms combined with DNA, RNA and protein molecules was determined in the subcellular fractions prepared by the method of Schneider (1961). Thus, the Do's given as the drug concentrations were substituted for the number of Pt atoms combined with each fraction. Then the efficiency of the Pt atom to kill the cells was expressed as the reciprocal of the number of Pt atoms combined and was calculated for each molecule. The efficiency for DNA was 2.47, 2.75, 9.49, 9.66, 10.53 and 15.00 x 10(4) nucleotides respectively for the conditions described above. A detailed comparison of the Do's and efficiencies suggested that the supra-additive effect of the combination treatment could be explained by two mechanisms, i.e. the increased drug level in DNA (from 37 to 42 degrees C) and the increased efficiency of the Pt atoms to kill the cells (> 42 degrees C).

Cell Death↗

PubMed1994

Effect of hypothermia on the in vitro potencies of neuromuscular blocking agents and on their antagonism by neostigmine.

The effect of temperature on the potencies of neuromuscular blocking agents remains unclear. This study was undertaken to examine the effects of different neuromuscular blocking agents at 37 and 27 degrees C at a constant carbon dioxide content (alpha stat principle). The effect of neostigmine 1 mumol litre-1 induced antagonism of these agents was also investigated. Phrenic nerve-hemidiaphragm preparations of rats were mounted in modified Krebs solution, maintained at 37 degrees C and aerated with a 5% carbon dioxide-95% oxygen gas mixture, and at 27 degrees C with 4% carbon dioxide to maintain the carbon dioxide content of the solution constant. Phrenic nerves were stimulated with 0.1-Hz supra-maximal impulses of 0.2-ms duration and the elicited tension of the diaphragm recorded. The potencies of the steroidal neuromuscular blocking agents (rocuronium, vecuronium, pancuronium and pipecuronium) increased significantly at 27 degrees C (P < 0.05), while the potencies of the benzylisoquinolinium agents (tubocurarine and dimethyltubocurarine) did not change. Neostigmine-induced antagonism of the steroidal agents did not differ significantly between each other but differed significantly from the benzylisoquinolinium agents (P < 0.05) at both temperatures. The ratios of IC50 (inhibitory concentration, 50%) with and without neostigmine at hypothermia were slightly higher for the steroidal agents, indicating slight enhancement of antagonism by neostigmine at 27 degrees C. In contrast, the ratios were significantly greater at 27 degrees C (P < 0.05) for isoquinolinium agents, implying significant enhancement of antagonism. Our results indicate that at 27 degrees C the potency of all steroidal agents increased and neostigmine-induced antagonism was slightly enhanced.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

Cloning and expression of cDNA coding for a new allergen from the house dust mite, Dermatophagoides farinae: homology with human heat shock cognate proteins in the heat shock protein 70 family.

An immunoreactive clone, which shares no homology with the major allergens, Der f I and Der f II, was isolated by screening of a Dermatophagoides farinae cDNA library with rabbit antiserum raised against an extract of the house dust mite and sera from patients with mite allergy. The deduced amino acid sequence of the cDNA of the clone is significantly homologous, up to 65.5%, to the carboxyl-terminal region of the heat shock cognate protein (hsc) 71 in the heat shock protein (hsp) 70 family. A pool of the recombinant protein-specific IgE purified from mite-allergic sera recognized a 67 kDa protein on a blot of ATP-binding components partially purified from the mite body extract, while the antibody did not bind to the major allergens. We conclude that the recombinant protein, one of several important allergens, may be a protein in the heat shock protein 70 family from the house dust mite, D. farinae.

Allergens↗

PubMed1994

A cooperative randomized controlled study of adjuvant chemoendocrine therapy for breast cancer in Japan.

A randomized trial was carried out in 55 Japanese institutions to examine the significance of postoperative adjuvant chemoendocrine therapy in Stages II and IIIA breast cancer patients after radical mastectomy. A total of 619 patients were entered from November 1982 to November 1984, of whom 554 were eligible. Patients were administered MMC (13 mg/m2) after surgery, and were randomized by the envelope method into either group A (ftorafur, 400 mg/m2/day; 275 patients), or group B (ftorafur, 400 mg/m2/day, and tamoxifen, 20 mg/day; 279 patients). Treatment was continued for 1 year from postoperative day 7. There were no significant differences between the two groups with regard to age, menopausal status, ER status, method of operation, stage, or number of positive lymph nodes. There was also no significant difference between the two groups in the 5-year survival and disease-free survival (DFS) rates (Kaplan-Meier method). Stratification by ER status, nodal status, or menopausal status produced no significant differences between the groups. However, postmenopausal patients and lymph node-positive patients who were also ER-positive showed a significantly higher DFS in group B. Furthermore, group B in ER-positive patients with four or more positive lymph nodes also had a higher survival rate.

Adult↗

PubMed1994

Hyperbaric oxygen combined with nicardipine administration accelerates neurologic recovery after cerebral ischemia in a canine model.

OBJECTIVE: To evaluate the efficacy of combined therapy--hyperbaric oxygenation with nicardipine administration--for neurologic recovery after complete cerebral ischemia. DESIGN: Randomized, prospective, controlled, unblinded, study, with 14-day postischemic observation. SETTING: Laboratory of the Department of Anesthesiology, Tohoku University School of Medicine. SUBJECTS: Nineteen healthy mongrel dogs (mean weight 10.4 kg) divided randomly into two groups-ten dogs in the untreated group and nine dogs in the treated group. INTERVENTIONS: Fifteen minutes of complete global cerebral ischemia was achieved by occlusion of the ascending aorta and the caval veins. Dogs in the treated group each received a 0.01-mg/kg bolus injection of nicardipine immediately after the reestablishment of circulation, followed by a 0.03-microgram/kg/min continuous infusion of nicardipine for 3 days and hyperbaric oxygen therapy with 3 atmospheres absolute pressures in an FIO2 of 1.0 for 1 hr at 3, 24, and 29 hrs after ischemia. Neurologic recovery was evaluated based on the survival time and rate, the Electroencephalogram (EEG) Score (1 = normal, 5 = isoelectric), and the Neurologic Recovery Score (100 = normal, 0 = brain dead) over a 14-day postischemic period. MEASUREMENTS AND MAIN RESULTS: Neurologic Recovery Scores of the treated group were always higher than those scores of the untreated group throughout the 14-day period. The best Neurologic Recovery Score was 83.1 +/- 5.3 in the treated group and 46.9 +/- 5.2 in the untreated group (p < .01). The numbers of dogs that recovered to a Neurologic Recovery Score of > 85 (assessed as almost normal) was five of nine in the treated group and none of ten in the untreated group (p < .01). Recovery of EEG over 14-day period was better in the treated group. The survival rate and the predicted survival rate were 78% and 13.6 days in the treated group and 30% and 9.0 days in the untreated group, respectively (p < .04 for the survival rate and p < .05 for the survival time). CONCLUSION: Combined therapy, using hyperbaric oxygenation with nicardipine administration, given after 15 mins of complete global cerebral ischemia, accelerates neurologic recovery in dogs.

Animals↗

PubMed1994

A major pathogenic antigen of Heymann nephritis is present exclusively in the renal proximal tubule brush border--studies with a monoclonal antibody against pronase-digested tubular antigen.

We have isolated a nephritogenic 120-kD antigen from rat renal tubule brush border that induces rat Heymann nephritis. A MoAb that recognized this antigen reacted exclusively with the brush border on indirect immunofluorescence and immunoelectron microscopy. Rabbit antiserum against this antigen also reacted exclusively with the brush border. With the injection of this antiserum, rabbit IgG became detectable along the glomerular basement membrane (GBM) after 3 days. Our 120-kD antigen was shown to have a close relationship with gp330 based on the following: (i) this antigen can induce active Heymann nephritis as gp330; (ii) our MoAb reacted with the immune deposits of nephritic kidneys induced not only by the 120-kD antigen but also by gp330, and conversely, rabbit antiserum against gp330 reacted with those induced by the 120-kD antigen as well as gp330; and (iii) by immunoblotting, polyclonal antibodies against the 120-kD antigen reacted with gp330 and polyclonal antibodies against gp330 reacted with the 120-kD antigen. These observations indicate that antigen present exclusively in the brush border can induce active Heymann nephritis, and the common antigenic determinants shared by brush border and the coated pits of glomerular epithelium may not be a prerequisite to induce nephritis. A more precise relationship between the 120-kD antigen and reported C14 fusion protein or 40-kD alpha 2MRAP remains to be established.

Animals↗

PubMed1994

Rate-limiting steps in activation of cardiac Cl- current revealed by photolytic application of cAMP.

Single myocytes were obtained from guinea-pig ventricles, and the catecholamine-induced Cl- current (ICl) was recorded by the patch-clamp method combined with the use of caged adenosine 3',5'-cyclic monophosphate (cAMP) and the concentration jump technique. The rapid bath application of isoprenaline was followed by a marked latency of approximately 1.7 s before a sigmoidal onset of the ICl activation, while the photolysis of caged cAMP was followed by no measurable latency. The ICl conductance was increased by increasing the concentration of caged cAMP with a threshold of approximately 5 microM and a one-half effective concentration of 25 microM. On the other hand, the rate of the activation increased in proportion to the logarithm of the concentration of caged cAMP. When the ultraviolet flash was repeated or the myocytes were pretreated with either forskolin, 3-isobutyl-1-methylxanthine, or okadaic acid, the rate of the ICl activation accelerated, and the whole time course of the ICl activation became monoexponential. These findings suggest that both the production of cAMP and reactions on the multiple phosphorylation sites of the channel protein are major rate-limiting steps in the ICl activation.

1-Methyl-3-isobutylxanthine↗

PubMed1994

Increased excretion of urinary transforming growth factor beta in patients with focal glomerular sclerosis.

The urinary transforming growth factor beta (TGF-beta) excretion was measured in 33 patients including 10 with systemic lupus erythematosus (SLE), 8 with focal glomerular sclerosis (FGS), 9 with IgA nephropathy (IgAN), and 6 with membranous nephropathy (MN), and in 7 healthy subjects by enzyme-linked immunosorbent assay using a monoclonal antibody specific for TGF-beta 1 + 2 + 3. A significantly increased urinary TGF-beta excretion was observed in FGS patients (555.5 +/- 458.4 ng/mg Cr) as compared with normal controls (46.9 +/- 43.9 ng/mg Cr) (p < 0.05) and a relative increase in SLE patients (96.4 +/- 58.2 ng/mg Cr) and a decrease in MN patients (24.8 +/- 13.3 ng/mg Cr). In contrast, there was no difference in TGF-beta excretion between IgAN patients (54.1 +/- 37.4 ng/mg Cr) and normal controls. A correlation between the amount of proteinuria and TGF-beta was not found. As has been previously demonstrated in experimental studies, TGF-beta may play a similar role in human glomerular diseases. The results obtained in this study raised the possibility that extracellular matrix might be produced by glomerular cells in vivo under the control of TGF-beta and that TGF-beta might act as a stimulator for the development of glomerulosclerosis.

Adolescent↗

PubMed1994

Formation of amyloid-like substance from beta-2-microglobulin in vitro. Role of serum amyloid P component: a preliminary study.

Although the pathogenesis has yet to be fully understood, beta 2-microglobulin (beta 2m) related amyloidosis is a frequent complication in long-term hemodialysis (HD) patients. In an attempt to clarify the association of two potential candidates with amyloidogenesis from beta 2m in HD patients, human urine-derived beta 2m solution alone or combined with glycosaminoglycans: hyaluronic acid, heparan sulfate, or serum amyloid P component (SAP) were dialyzed against physiological buffered solution (pH 7.4) using a microdialyzer in vitro for 72 h at 4 degrees C. This study demonstrates for the first time that SAP can play a crucial role in the formation of amyloid-like fibrils from beta 2m. This occurs by a direct influence on either the processing of a precursor protein, or protein folding, in vitro, by a short-period dialysis against a physiological buffered solution.

Amyloid↗

PubMed1994

Cloning and characterization of cDNA coding for a new allergen from the house dust mite, Dermatophagoides farinae.

A cDNA clone encoding a new allergen from the Dermatophagoides farinae cDNA lambda gt11 library was isolated and sequenced. There was no amino acid sequence homology with other known allergens. The gene product, beta-galactosidase fusion protein, of the truncated cDNA on blot reacted with IgE in 13 of 43 sera from patients allergic to mites. The affinity-purified fusion protein had a potent ability to release histamine from washed blood cells of the mite-allergic patients. Human specific IgE eluted from the fusion protein band on blots recognized a 39-kD component on blots of a mite body extract.

Allergens↗

PubMed1994

Structure of IgE epitopes on a new 39-kD allergen molecule from the house dust mite, Dermatophagoides farinae.

Two IgE epitope sequences comprising Ser56-Pro-Val-Thr-Lys-Arg-Ala-Ser-Leu-Lys-Ile-Asp-Ser-Lys-Lys70 and Asp104-Val-Glu-Leu-Ser-Leu-Arg-Ser-Ser-Asp-Ile-Ala115 were identified by deletion analysis of the cDNA encoding a new 39-kD protein of mite allergen. A synthetic dodecapeptide corresponding to the latter epitope sequence functioned as a monovalent and mite-specific hapten. Replacement of each of the 12 amino acid residues with Gly, using site-directed mutagenesis, indicated that Arg110 may play a central role in IgE binding. However, the 8 allergic sera tested exhibited a wide variation in their amino acid residues required for reactivity to IgE in allergic sera.

Allergens↗

PubMed1994

B cell mitogenic activity of sea squirt antigen.

The activity of sea squirt antigen, one of the allergy-inducing substances for humans, on murine and human lymphocytes was studied in vitro. Sea squirt antigen stimulated normal mouse spleen cells to proliferate, as detected by [3H]-TdR incorporation, in a dose-dependent manner. The responder cells are B cells because the response was reduced by the treatment of spleen cells with anti-immunoglobulin antibody and complement and passing through a nylon wool column, but not with anti-Thy-1 antibody and complement. Spleen cells of C3H/HeJ mice, which are lipopolysaccharide low responders, were also stimulated as well as spleen cells of C3H/HeN mice, suggesting that this response is not due to lipopolysaccharide in the antigen fraction. Sea squirt antigen stimulated not only proliferative response of B cells, but also polyclonal immunoglobulin production. Furthermore, sea squirt antigen also stimulated human lymphocytes to proliferate and to produce immunoglobulin. All these results suggest that sea squirt antigen has mitogenic activity on B cells, and this ability is concerned with the induction of allergic reaction.

Animals↗