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K Matsuda

Publications and source records attributed to K Matsuda.

At least 163 records · Page 9Linked to original sources
PubMed2000

[Two cases of nephrogenic adenoma in the bladder diverticulum].

We report two cases of a nephrogenic adenoma in the bladder diverticulum. The first patient was an 81-year-old man with gross hematuria. Cystoscopy revealed bladder diverticulum and a papillary tumor within. Bladder diverticulectomy was performed and the histopathological diagnosis was a nephrogenic adenoma. The second patient was a 50-year-old man with gross hematuria and dysuria. Transabdominal ultrasound revealed bladder diverticulum. Transurethral coagulation of the bladder diverticulum was performed. Then three papillary tumors were detected, and were resected transurethrally. The histopathological diagnosis was a nephrogenic adenoma. These are the first and second cases of a nephrogenic adenoma in the bladder diverticulum reported in Japan.

Adenoma↗
PubMed2000

[Evaluation of antibiotics by the method of initial bactericidal activity].

Minimum inhibitory concentration (MIC) has been generally used to evaluate the activity of antimicrobial agents. However, there is some discrepancy between clinical efficacy and the MIC value. We studied the relationship between initial bactericidal activity of imipenem (IPM), panipenem (PAPM), meropenem (MEPM), ceftazidime (CAZ) and amikacin (AMK) and the respective MIC values against Pseudomonas aeruginosa PAO1. Initial bactericidal activity was defined as percent reduction of initial bacterial cell concentration (10(6) cells/ml) after 1 hour incubation following addition of antibiotic. The concentration of antibiotic used in this experiment was the blood level of each antibiotic at 3 hours after administration by drip infusion of the usual dose (IPM, PAPM and CAZ were 1 g for 1 hour drip infusion, MEPM was 1 g for 0.5 hours drip infusion and AMK was 200 mg for 1 hour drip infusion, respectively). The antibiotic concentration of IPM, PAPM, MEPM, CAZ and AMK were 8.77 micrograms/ml, 6.37 micrograms/ml, 4.12 micrograms/ml, 12.0 micrograms/ml and 5.18 micrograms/ml, respectively. MICs of IPM, PAPM, MEPM, CAZ and AMK were 2 micrograms/ml, 64 micrograms/ml, 1 microgram/ml, 1 microgram/ml and 2 micrograms/ml, respectively. Initial bactericidal activity of IPM, PAPM, MEPM, and CAZ against P. aeruginosa PAO1 was 98.2%, 86.1%, 48.1%, and 43.4% reduction in bacterial concentration, respectively. AMK shows the strongest initial bactericidal activity with more than 99.9%. The killing speed of IPM was obviously the most rapid among the three carbapenems. The MIC of PAPM was significantly higher than the other antibiotics, and the initial bactericidal activity of PAPM was second to IPM. We can classify antibiotics into two groups based on initial bactericidal activity against P. aeruginosa; one class is antibiotics having rapid initial killing such as AMK, IPM and PAPM, the other is CAZ, MEPM showing slow initial killing.

Amikacin↗
PubMed1999

Cis-acting DNA elements of mouse granulocyte/macrophage colony-stimulating factor gene responsive to oxidized low density lipoprotein.

We previously demonstrated that the induction of granulocyte/macrophage colony-stimulating factor (GM-CSF) played an important role in oxidized low density lipoprotein (Ox-LDL)-induced macrophage growth as a growth priming factor. The present study was undertaken to elucidate the transcriptional regulation of the GM-CSF gene using Raw 264.7 cells, a mouse macrophage cell line. Transient transfection into Raw 264.7 cells of several 5'-flanking regions of GM-CSF gene-luciferase fusion plasmids revealed the presence of two positive regulatory sites in regions spanning from -97 to -59 and from -59 to -37 and one negative regulatory site from -120 to -97 in unstimulated cells. When cells were stimulated by Ox-LDL, there was one positive responsive site from -225 to -120 and one negative responsive site from -97 to -59, which contained the NF-kappaB binding site. Computer analysis revealed the presence of a putative AP-2 binding site from -169 to -160. Mutagenesis of a putative AP-2 binding site and tandem repeat of this site in plasmid resulted in a complete loss and increased responsiveness to Ox-LDL, respectively. Electrophoretic mobility shift assay showed that Ox-LDL increased the binding of certain nuclear protein(s) to a putative AP-2 binding site but decreased their binding to NF-kappaB binding site. Supershift assay showed that nuclear proteins bound to NF-kappaB binding site contained, at least, p50 and p65 but could not demonstrate nuclear protein(s) bound to a putative AP-2 binding site. Our results suggested that a putative AP-2 binding site from -169 to -160 was a positive responsive element to Ox-LDL and that the NF-kappaB binding site from -91 to -82 was a negative responsive element in Ox-LDL-induced GM-CSF transcription.

Animals↗
PubMed1999

Synthesis and anti-Helicobacter pylori activity of FR182024, a new cephem derivative.

The synthesis and anti-Helicobacter pylori activity of a novel cephem derivative FR182024 (1) are described. FR182024 having a (5-methyl-1,3,4-thiadiazol-2-yl)-thio moiety at the 3-position and a phenylacetamido at the 7-position was found to have extremely potent in vitro anti-H.pylori activity, superior therapeutic efficacy to AMPC and CAM, and low potential for causing diarrhea.

Amoxicillin↗
PubMed1999

Chronopharmacology for deoxyspergualin: toxicity and efficacy in the rat.

BACKGROUND: Deoxyspergualin (DSG), a potent immunosuppressive drug, has been clinically used as a rescue therapy for acute graft rejection. However, DSG has severe adverse effects that limits its use. Here, we examined the optimized therapeutic protocol for DSG using chronopharmacological profiles of it. METHODS: First, a dosing time-dependent difference in the toxicity and efficacy of DSG was determined using a heterotopic heart transplantation model. Second, chronokinetics of DSG were examined to reveal the mechanism for dosing time-dependent differences in the effect. RESULTS: In rats treated with DSG at the active period, bone marrow suppression and damage of small intestine were significantly severe. However, no significant difference was found in cardiac allograft survival and pharmacokinetics according to the timing of drug administration. CONCLUSIONS: The toxicity of DSG varied with the dosing time, whereas its efficacy did not. The chronopharmacological approach may provide merits for immunosuppressive therapy with DSG in clinical organ transplantation.

Animals↗
PubMed1999

An IKLLI-containing peptide derived from the laminin alpha1 chain mediating heparin-binding, cell adhesion, neurite outgrowth and proliferation, represents a binding site for integrin alpha3beta1 and heparan sulphate proteoglycan.

We synthesized and characterized several peptides containing the IKLLI sequence in the alpha1 chain of laminin-1. The IKLLI-containing peptides, such as LA4 (CSRNLSEIKLLISRARK), LA5 (EIKLLIS) and LA5L (SEIKLLIS), were found to mediate heparin binding and cell adhesion, while also promoting neurite outgrowth in PC12 cells. Furthermore, peptides LA4 and LA5 also mediated proliferation. However, a scrambled peptide, LA5S (ILEKSLI), did not show any of these activities. Anti-LA4 antibodies inhibited laminin- and LA5-mediated cell adhesion and neurite outgrowth, and anti-(integrin alpha3) and anti-(integrin beta1) antibodies inhibited LA5-mediated cell adhesion and neurite outgrowth. Heparin and heparan sulphate inhibited LA5-mediated heparin binding and PC12 cell adhesion in a dose- dependent manner. The IC50 for inhibition of heparin binding and cell adhesion was observed with 9 microM and 8 microM heparin/heparan sulphate respectively. Furthermore, heparan sulphate proteoglycan also inhibited LA5-mediated PC12 cell adhesion with an IC50 of 100 micrograms/ml. However, chondroitin sulphate (dermatan sulphate) did not inhibit cell adhesion. These data suggest that an IKLLI-containing peptide derived from the laminin alpha1 chain may be an active site of laminin and that its cell adhesion may thus interact with both integrin alpha3beta1 and cell- surface heparan sulphate proteoglycan.

Amino Acid Sequence↗
PubMed1999

Laminin inhibits both Abeta40 and Abeta42 fibril formation but does not affect Abeta40 or Abeta42-induced cytotoxicity in PC12 cells.

Laminin has recently been reported to inhibit both Abeta40 and Abeta42 fibril formation in vitro. Laminin was thus suggested to be an effective therapeutic agent for Alzheimer's disease. However, some recent reports have shown that Abeta fibril formation may not necessarily be linked to the development of Abeta neurotoxicity. In the present study, we thus investigated whether or not laminin affects Abeta40 and Abeta42-induced neurotoxicity. The findings of the present study by using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) dye reduction test showed laminin not to have an inhibitory effect on Abeta40 or Abeta42-induced cytotoxicity in PC12 cells while Abeta fibril formation was inhibited under the conditions used in the present study. The findings of the present study therefore do not support the hypothesis that Abeta fibril formation is absolutely required for the development of Abeta cytotoxicity.

Amyloid beta-Peptides↗
PubMed1999

Assessment of regional and global left ventricular function by reinjection T1-201 and rest Tc-99m sestamibi ECG-gated SPECT: comparison with three-dimensional magnetic resonance imaging.

OBJECTIVES: The purpose of this study was to test the ability of reinjection thallium-201 and rest technetium-99m sestamibi ECG (electrocardiographic)-gated SPECT (i.e., reinjection-g-SPECT [single-photon emission computed tomography] and MIBI-g-SPECT) to determine regional and global functional parameters. BACKGROUND: The ECG-gated perfusion SPECT was reported to provide accurate left ventricular ejection fraction (LVEF) using an automated algorithm. We hypothesized that other various functional data may be obtained using reinjection-g-SPECT and MIBI-g-SPECT. METHODS: Reinjection-g-SPECT, MIBI-g-SPECT, and three-dimensional magnetic resonance imaging (3DMRI) were conducted in 20 patients with coronary artery disease. Regional wall motion (RWM) and wall thickening (RWT) were analyzed using semiquantitative visual scoring by each g-SPECT and 3DMRI. The left ventricular end-systolic and end-diastolic volumes (EDV, ESV) and LVEF estimated by reinjection- and MIBI-g-SPECT were compared with the results of 3DMRI. RESULTS: A high degree of agreement in RWM and RWT assessment was observed between each g-SPECT and 3DMRI (kappa >.70, p < .001). The LVEF values by reinjection- and MIBI-g-SPECT correlated and agreed well with those by 3DMRI (reinjection: r = .92, SEE = 5.9%, SD of differences = 5.7%; sestamibi: r = .94, SEE = 4.4%, SD of differences = 5.1%). The same also pertained to EDV (reinjection: r = .85, SEE = 18.7 ml, SD of differences = 18.4 ml; sestamibi: r = .92, SEE = 13.1 ml, SD of differences = 13.0 ml) and ESV (reinjection: r = .94, SEE = 10.3 ml, SD of differences = 10.3 ml; sestamibi: r = .97, SEE = 6.7 ml [p < .05 vs. reinjection by F test], SD of differences = 6.6 ml [p < .05 vs. reinjection by F test]). CONCLUSIONS: Reinjection- and MIBI-g-SPECT provide clinically satisfactory various functional data. These functional data in combination with the perfusion information will improve diagnostic and prognostic accuracy without an increase in cost or the radiation dose to the patients.

Adult↗
PubMed1999

Reactive oxygen species play an important role in the activation of heat shock factor 1 in ischemic-reperfused heart.

BACKGROUND: The myocardial protective role of heat shock protein (HSP) has been demonstrated. Recently, we reported that ischemia/reperfusion induced a significant activation of heat shock factor (HSF) 1 and an accumulation of mRNA for HSP70 and HSP90. We examined the role of reactive oxygen species (ROSs) in the induction of stress response in the ischemic-reperfused heart. METHODS AND RESULTS: Rat hearts were isolated and perfused with Krebs-Henseleit buffer by the Langendorff method. Whole-cell extracts were prepared for gel mobility shift assay using oligonucleotides containing the heat shock element. Induction of mRNA for HSP70 and HSP90 was examined by Northern blot analysis. Repetitive ischemia/reperfusion, which causes recurrent bursts of free radical generation, resulted in burst activation of HSF1, and this burst activation was significantly reduced with either allopurinol 1 mmol/L (an inhibitor of xanthine oxidase) or catalase 2x10(5) U/L (a scavenger of H2O2). Significant activation of HSF1 was observed on perfusion with buffer containing H2O2 150 micromol/L or xanthine 1 mmol/L plus xanthine oxidase 5 U/L. The accumulation of mRNA for HSP70 or HSP90 after repetitive ischemia/reperfusion was reduced with either allopurinol or catalase. CONCLUSIONS: Our findings demonstrate that ROSs play an important role in the activation of HSF1 and the accumulation of mRNA for HSP70 and HSP90 in the ischemic-reperfused heart.

Allopurinol↗
PubMed1999

The occurrence of an abdominal wall abscess 11 years after appendectomy: report of a case.

Most complications after appendectomy occur within 10 days; however, we report herein the unusual case of a patient in whom a wound abscess was detected more than 10 years after an appendectomy. A 26-year-old woman presented to our hospital with nausea and vomiting, pain, and a mass in the right lower abdominal wall. She had undergone an appendectomy 11 years previously. Physical examination revealed a tender mass, 5 cm in diameter, under the appendectomy scar. An abdominal ultrasonography demonstrated a low-echoic mass lesion measuring 9.0 x 5.0 x 2.0 cm. Incision of the connective tissue revealed about 3 ml of cream-colored and odorless fluid in the abscess cavity. Fistulography revealed an abscess cavity not communicating with the bowel lumen. Floss was discovered in the connective tissue and removed. Debridement of the abscess wall was performed and a piece of the wall was sent for histologic examination. Pathological examination revealed panniculitis of the subcutaneous tissue, and panniculitis with granulation and granuloma of the abscess wall. This case report demonstrates that a preoperative diagnosis should be based not on one finding, but on all findings collected, inclusively.

Abdominal Abscess↗
PubMed1999

Aortic dissection complicating cardiac surgery in a patient with calcified ascending aorta.

Aortic dissection is a rare but devastating complication of cardiac surgery. Adequate and early diagnosis of intraoperative aortic dissection and quick therapeutic decision making are the keys for saving patients in such cases. We describe the case of a 68-year-old man referred for CABG and mitral valve replacement with severe calcification of the ascending aorta. Intra-operative transesophageal echocardiography was useful for diagnosis of intra-operative aortic dissection and malperfusion of the true lumen. Immediate switching of the arterial perfusion site established flow in the true lumen with prompt subsidence of the expanded false lumen. CABG, mitral valve replacement and graft replacement of the ascending aorta could be simultaneously performed in this patient.

Aged↗
PubMed1999

Overexpression of dominant negative mutant hepatocyte nuclear factor (HNF)-1alpha inhibits arginine-induced insulin secretion in MIN6 cells.

AIMS/HYPOTHESIS: To explain the mechanisms whereby mutations in the HNF-1alpha gene cause insulin secretory defects. METHODS: A truncated mutant HNF-1alpha (HNF-1alpha288t) was overexpressed in hepatoma cells (HepG2) and murine insulinoma cells (MIN6) using a recombinant adenovirus system and expression of the HNF-1alpha target genes and insulin secretion were examined. RESULTS: Expression of phenylalanine hydroxylase and alpha1-antitrypsin genes, the target genes of HNF-1alpha, was suppressed in HepG2 cells by overexpression of HNF-1alpha288t. In MIN6 cells, overexpression of HNF-1alpha288t did not change insulin secretion stimulated by glucose (5 mmol/l and 25 mmol/l) or leucine (20 mmol/l). Potentiation of insulin secretion by arginine (20 mmol/l, in the presence of 5 mmol/l or 25mmol/l glucose) was, however, reduced (p < 0.0001 and p = 0.027, respectively). Similarly reduced responses were observed when stimulated with homoarginine. Expression of the cationic amino acid transporter-2 was not reduced and insulin secretory response to membrane depolarization by 50 mmol/l KCl was intact. CONCLUSION/INTERPRETATION: The HNF-1alpha288 t, which is structurally similar to the mutant HNF-1alpha expressed from the common MODY3 allele, P291fsinsC, exerts a dominant negative effect. Suppression of HNF-1alpha in MIN6 cells severely impaired potentiation of insulin secretion by arginine, whereas glucose-stimulated and leucine-stimulated insulin secretion was intact. Our findings delineate the complex nature of beta-cell failure in patients with MODY3. This cell model will be useful for further investigation of the mechanism of insulin secretory defects in these patients.

Animals↗
PubMed1999

Revision surgery after triple-cup arthroplasty.

Although various operative procedures have been applied for advanced or terminal osteoarthritis of the hip joints in relatively young patients, the long-term results are controversial. Since 1974, we have performed the triple-cup arthroplasty developed by Aoki in 110 patients who were comparatively young. The triple-cup assembly is composed of stainless-steel outer and inner cups between which a high density polyethylene cup is incorporated, so that there are basically four mobile surfaces, but the major movement is actually taking place between the outer cup and the plastic cup [8]. We have sometimes encountered migration of the cups, which caused hip joint pain and decreased the range of motion. Revision surgery was required for 25 hip joints in 21 patients (23%). The acetabulum was very thin in almost all cases, so that reaming of the cavity had to be restricted to the minimum possible. The femoral head in the cup was often covered with a layer of fibrous tissue. We could utilize the femoral head as a bone graft, even though the residual volume of bone varied in each case. The result of revision surgeries after the triple-cup arthroplasty was good clinically and radiographically at last follow-up.

Adult↗
PubMed1999

Gallbladder torsion: case report and review of 245 cases reported in the Japanese literature.

We report here a case of torsion of the gallbladder in a 73-year-old woman. The patient was admitted to our hospital with right hypochondralgia. Ultrasonography and computed tomography demonstrated a distended gallbladder, with a multilayered wall, which contained no stones. Since the symptoms did not respond to antibiotics, laparotomy was performed. The gallbladder was found to be twisted around its pedicle and to be gangrenous. Cholecystectomy was performed, and the patient had an uneventful postoperative course. We also reviewed 245 cases reported in the Japanese literature. The clinical features of gallbladder torsion, which include low frequency of fever and jaundice, poor response to antibiotic therapy, and acute onset of abdominal pain, may be helpful in the differential diagnosis from acute cholecystitis. Moreover, a highly suggestive sign of gallbladder torsion observed by ultrasonography or computed tomography is a markedly enlarged "floating" gallbladder with a continuous hypoechoic line indicating edematous change in the wall.

Abdomen, Acute↗
PubMed1999

Rapid growth of residual colonic tumor after incomplete mucosal resection.

We report an 89-year-old man with colon cancer that developed rapidly after an incomplete endoscopic mucosal resection (EMR), and discuss the adverse effect of this maneuver on the tumor biology. A sessile polyp, 15 mm in size, was detected at the hepatic flexure. EMR was performed immediately. Histological examination showed well differentiated adenocarcinoma with an adenomatous component invading the submucosal layer. There was vascular invasion (positive on elastica van Gieson staining) and the surgical margin was positive for cancer. A right hemicolectomy was performed. The surgical specimen showed the residual tumor, 22 mm in diameter. The relevant histopathological findings of the surgical specimen were: well differentiated adenocarcinoma, with partly mucinous carcinoma and a tubular adenomatous component, depth muscularis propria (mp), lymph node (LN) (0/9). Most of the submucosally invasive cancer was resected by the initial EMR, but the small residual tumor showed rapid growth within only 3 months after the EMR. It was assumed that the residual tumor cells had acquired more malignant characteristics after EMR. In regard to EMR we propose that: (1) except for patients who are at high risk for a major operation, EMR should be avoided for carcinoma with massive submucosal invasion, (2) colonic resection should be performed immediately when histology shows a positive surgical margin for carcinoma, and (3) patients operated after an incomplete EMR should be watched very carefully for the detection of recurrence.

Adenocarcinoma↗
PubMed1999

Severe complications of ulcerative colitis after high-dose prednisolone and azathioprine treatment.

We report a rare case of ulcerative colitis (UC) associated with methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa infections in multiple organs, and with compressive fracture from osteoporosis after the administration of high-dose prednisolone and azathioprine. A 25-year-old man had been treated with high-dose prednisolone for UC. He suddenly experienced severe lumbago, which prevented him from walking. Plain X-ray demonstrated compressive fractures of the thoracic and the lumbar vertebrae, which were thought to be due to osteoporosis as a side effect of the high-dose prednisolone. At this admission, in another hospital, he also had a bloody discharge from the rectum, and azathioprine was started; however, the patient's condition still did not show any improvement. The total doses of azathioprine and prednisolone he had received were 3150 mg and more than 15,000 mg, respectively. Considering the presence of the serious complications, surgical intervention was the treatment selected. Culture study revealed MRSA in the feces and nasal cavity, and P. aeruginosa in the feces and urine. Vancomycin hydrochloride and gentamicin were administered, and were effective, with a subsequent negative culture study. Subtotal colectomy with mucus fistula was performed. After the operation, culture studies remained negative. Major steroid side effects such as bone fracture and osteoporosis should be considered as an indication for surgery in UC patients. MRSA and P. aeruginosa are a menace, especially for UC immunosuppressed patients on steroid or immunosuppressive therapy. When these bacteria are detected, there should be prompt and adequate antimicrobial therapy against the organisms and the immunosuppressive therapy should be immediately discontinued. We conclude that surgical therapy should be considered in the earlier stage for patients with intractable UC, rather than continuing long-term administration of steroid or azathioprine, which may lead to serious complications.

Adult↗
PubMed1999

Evaluation of a compressive-type skeletal muscle pump for cardiac assistance.

BACKGROUND: Recent investigations have focused on using the latissimus dorsi muscle for cardiac assistance. Although cardiomyoplasty has been applied clinically, other procedures remain experimental, but promising, modes of cardiac assistance. We assessed the latissimus dorsi muscle as an in situ energy source for circulatory assist devices. METHODS: We developed a pneumatic chamber as a compressive-type muscle actuator. The chamber was implanted under the latissimus dorsi muscle and converted contractile power into pneumatic pressure. The effect of chamber position and size and the influence on muscle blood flow were examined. After muscle conditioning, the pump performance of a circulatory assist device driven by the chamber was evaluated. RESULTS: The chamber functioned better when placed in the proximal position of the latissimus dorsi muscle. The size affected the generated pneumatic pressure, and the higher resting pressure of the chamber reduced the muscle blood flow. The maximum stroke work of the circulatory assist device was greater than that of the right ventricle but less than that of the left ventricle. The chamber could drive the circulatory assist device against the systemic range of afterload in which a high preload was available. Long-term adhesion surrounding the chamber reduced the pressure generation capability. CONCLUSIONS: The compressive-type muscle actuator using the latissimus dorsi muscle generated acceptable hemodynamic work for right ventricular bypass or aortic counterpulsation.

Animals↗