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S Matsuo

Publications and source records attributed to S Matsuo.

At least 55 records · Page 3Linked to original sources
PubMed2000

Cephaloridine-induced inhibition of cytochrome c oxidase activity in the mitochondria of cultured renal epithelial cells (LLC-PK(1)) as a possible mechanism of its nephrotoxicity.

To clarify the mechanism of cephalosporin nephrotoxicity, the effects of cephaloridine (CLD), a nephrotoxic cephalosporin antibiotic, on the mitochondria of the pig kidney proximal tubular epithelial cell line LLC-PK(1) were studied in culture. The activity of cytochrome c oxidase in the mitochondria of LLC-PK(1) cells was significantly decreased from 9 h after addition of 1.0 mM CLD to the cultured cells. These effects were dose-dependent and accompanied with a significant decrease in the ATP content in the cells, followed by marked morphological changes in the mitochondria. These alterations were observed in the treated cells before the increase in lipid peroxidation. The activities of NADH-cytochrome c reductase and succinate dehydrogenase in the mitochondria and NADPH-cytochrome P450 reductase, NADH-cytochrome b(5) reductase, and 7-ethoxycoumarin O-deethylase in the microsomes of the treated cells were not affected. Superoxide anion production by the mitochondria prepared from LLC-PK(1) cells or NADH-cytochrome c reductase was not affected by addition of CLD (1-10 mM), but adriamycin (0.1 mM) or paraquat (0.1 mM) significantly increased the superoxide anion production. These results suggested that the primary action of CLD is inhibition of cytochrome c oxidase activity in the mitochondrial electron transport chain, which decreases intracellular ATP content in renal tubular epithelial cells and that these effects of CLD are followed by increased lipid peroxidation and cellular injury.

Animals↗
PubMed2000

Determination of incorporated amounts of poly(ethylene glycol)-derivatized lipids in liposomes for the physicochemical characterization of stealth liposomes.

We describe a method for determining incorporated amounts of poly(ethylene glycol) (PEG)-derivatized lipids in liposomes for the physicochemical characterization of PEG-coated liposomes. This method is based on the spectrophotometric determination of complexes of polyethers with sodium ions after their extraction as picrates into 1,2-dichloroethane, developed by Favretto for measuring levels of polyoxyethylene alkylphenyl-ether non-ionic surfactants in waste water. The same assay was applied to the estimation of PEG-derivatized lipids in liposomes and percent incorporation of PEG-derivatized lipids into liposomes was successfully determined. To prevent the interference from liposomal lipids other than PEG-derivatized lipids in this assay, liposomal samples were diluted at least to a concentration of less than 0.2 mM. The percent incorporation of PEG-lipids varied, depending on the molecular weight of PEG and anchor acyl chain length in PEG-lipids and it was suggested that the percent incorporation of PEG-lipids into liposomes would be a good parameter of quality control of PEG-liposomes in manufacturing facility and the picrate method used in the present study allows for the determination of this parameter without the need for hazardous radioisotopes.

Calibration↗
PubMed2000

In situ photoaffinity labeling of proteasome with photoactive adriamycin analogue.

An intracellular adriamycin (ADM)-binding protein purified from the cytosol of L1210 mouse lymphocytic leukemia cells had a molecular weight of 700-1500 kDa and hydrolyzed Suc-LLVY-MCA. When L1210 cells were incubated with a photoactive ADM analogue, N-(p-azidobenzoyl)-adriamycin (NAB-ADM), most of the NAB-ADM was found to localize in the nuclei. In situ photoaffinity labeling of L1210 cells with NAB-ADM resulted in low protease activity in the cytosol and nuclear extracts and the cells showed selective photoincorporation of NAB-ADM into the proteasome. These results suggest that the proteasome is a translocator of ADM from the cytoplasm to the nucleus and might therefore become a new candidate for cancer chemotherapy.

Animals↗
PubMed2000

Are the anti-inflammatory effects of dexamethasone responsible for inhibition of the induction of enzymes involved in prostanoid formation in rat carrageenin-induced pleurisy?

Since anti-inflammatory steroids modulate multiple gene expression, including the expression of prostaglandin H synthase-2 and phospholipase A(2), at the molecular level, we studied the effects of dexamethasone on rat carrageenin-induced pleurisy to elucidate whether regulation of phospholipase A(2) and prostaglandin H synthase-2 expression is the primary mechanism of its anti-inflammatory action. Suppression of plasma exudation by a lower dose of dexamethasone (0.3 mg/kg) was almost equal to that by aspirin (100 mg/kg), but that by higher dexamethasone doses (3 and 30 mg/kg) was considerably stronger, suggesting the involvement of effects other than that on prostanoid formation. The lower dose of dexamethasone also significantly reduced the pleural exudate neutrophil count and prostanoid levels. However, this dose affected neither the prostaglandin H synthase-2 level nor the phospholipase A(2) activity in the exudate cells. The prostaglandin H synthase-2 level was affected only at the higher doses, while phospholipase A(2) activity was not. These results suggest that the anti-inflammatory effects of dexamethasone in acute inflammation cannot be ascribed to direct interference with prostanoid formation via suppression of phospholipase A(2) and prostaglandin H synthase-2 expression.

Animals↗
PubMed2000

Developmental dependency of Meissner corpuscles on trkB but not trkA or trkC.

The distribution of S100-immunoreactive (ir) corpuscular endings was examined in the palate of wildtype and knockout mice for trkA, trkB or trkC. In wildtype mice, S100-ir corpuscular endings were abundant at the top of palatal rugae. The endings contained 2-4 parallel arrays of S100-ir neurites. The distribution of S100-ir nerve endings in trkA and trkC knockout mice was similar to that in wildtype mice; S100-ir corpuscular endings were abundant in palates of the mutant mice. In trkB knockout mice, the palate was devoid of corpuscular endings, An immunoelectron microscopic method indicated that S100-ir corpuscular endings were identical to Meissner corpuscles. The normal development of Meissner corpuscles is probably dependent on trkB but not trkA or trkC.

Animals↗
PubMed2000

Constitutive activation of MAP kinase kinase (MEK1) is critical and sufficient for the activation of MMP-2.

We investigated the role of MEK1 signaling in MMP-2 activation by use of constitutive active/dominant negative forms of MEK1 and MEK1-specific inhibitor. We found that cell transformation with active forms of MEK1 dramatically increased secretion and proteolytic activation of MMP-2 and subsequently stimulated invasiveness of cells. Contrary, expression of dominant negative form of MEK1 in v-src-transformed cells or in Con A-activated cells resulted in the suppression of the augmented secretion and proteolytic activation of MMP-2. In addition, treatment of v-src-transformed cells with PD98059, a MEK1-specific inhibitor, strongly suppressed the secretion and activation of MMP-2, whereas treatment with wortmannin, a PI3 kinase inhibitor, showed no clear effect on MMP-2 secretion. Taken together, these results strongly suggest that MEK-MAP kinase signaling, but not PI3 kinase signaling, plays a critical role in the activation of MMP-2 secretion and, subsequently, in the invasiveness of v-src-transformed cells.

Animals↗
PubMed2000

Abolition of anti-glomerular basement membrane antibody-mediated glomerulonephritis in FcRgamma-deficient mice.

Several recent studies have demonstrated the central role of Fc receptors (FcR) rather than the complement system in triggering hypersensitivity reactions. We investigated the role of FcR for IgG (FcgammaR) using a murine model of accelerated anti-glomerular basement membrane (GBM) antibody-mediated glomerulonephritis as a representative of type II hypersensitivity diseases. Intravenous injection of rabbit anti-GBM antibody after preimmunization with normal rabbit IgG induced proteinuria and azotemia in wild-type C57BL/6 and CD40(+/-) mice but not in FcR gamma chain (FcRgamma)(-/-) mice or CD40(-/-) mice. Light microscopic findings revealed marked tissue damage in the glomeruli of wild-type C57BL/6 and CD40(+/-) mice. However, no tissue damage except polymorphonuclear cell infiltration was observed in the glomeruli of FcRgamma(-/-) mice. The glomeruli of CD40(-/-) mice were almost normal. Immunohistochemistry revealed the binding of rabbit IgG to the GBM in all mice injected with anti-GBM antibody. However, depositions of mouse IgG and complement to the glomeruli were not observed in CD40(-/-) mice, and deposition of fibrin was not observed in FcRgamma(-/-) or CD40(-/-) mice. These findings suggest that FcgammaR may initiate anti-GBM antibody-mediated renal disease. We conclude that FcgammaR rather than the complement system is critically involved in the development of type II hypersensitivity diseases.

Animals↗
PubMed2000

Small-cell carcinoma of the gallbladder: report of a case.

We report herein the case of an 81-year-old woman in whom a mass in the gallbladder was revealed by an ultrasound examination conducted as part of a follow-up study for a silent gallstone. The mass showed evidence of invasion into the adjacent liver parenchyma. Under the tentative diagnosis of malignant neoplastic disease originating in the gallbladder, a cholecystectomy with partial hepatectomy was performed. Histological examination of the tumor confirmed a diagnosis of small-cell carcinoma of the gallbladder, which is considered to be a rare type of neoplasm.

Aged↗
PubMed2000

Fluoride-induced ultrastructural changes in exocrine pancreas cells of rats: fluoride disrupts the export of zymogens from the rough endoplasmic reticulum (rER).

Influence of fluoride on exocrine pancreas cells was examined morphologically with traditional and prolonged osmium fixation techniques for electron microscopy in the enamel fluorosis model rats injected subcutaneously twice a day with 20 mg/kg body weight of sodium fluoride. Although the rough endoplasmic reticulum (rER) of exocrine pancreas cells in control rats was laminated and oriented parallel to the circumference of the nucleus, the rER of the cells in NaF-treated rats was dilated, disrupted the laminated arrangement, and changed to the globular-shape rER. Many intracisternal granules were formed in these globular-shape rER of the cells exposed to fluoride. Lots of autophagosomes were also seen in the exocrine cells with NaF treatment. The autophagosomes were limited with a double or multiple membranes, and contained cytoplasmic organelles and/or the intracisternal granules. The outer and inner leaflets of double membranes of the autophagosomes were usually separated by a distinct electron-lucent area. In prolonged osmium fixation, the area between the double membranes of the autophagosome was filled with osmiun reaction deposits. Many autophagosomes were encircled with the single or multiple osmiophilic layers. In some cases, the osmium positive saccules also surrounded the free surface of the globular-shape rER containing intracisternal granules. These findings indicate that fluoride disrupts the export of zymogens from the rER, resulting in formation of intracisternal granules and autophagosomes, and that the osmiophilic saccules participate in sequestration of cytoplasmic organelles in forming autophagosomes.

Animals↗
PubMed2000

Analysis of human abnormal walking using a multi-body model: joint models for abnormal walking and walking aids to reduce compensatory action.

This paper proposes new models of diseased joints and evaluates the effectiveness of walking aids such as a cane and a brace for compensating for lost functions due to joint disorders. The ZMJ concept described in the previous work (Yamashita and Tagawa, 1988. In: Radharaman (Ed.), Robotics and Factories of the Future'87. Springer, New York, pp. 670-677) is modified into three joint models as follows: a passive element joint (PEJ) which has a spring at the diseased joint; a constrained range joint (CRJ), the motion of which stays within some constrained relative angle; a partial moment joint (PMJ) which can produce a partial amount of the moment produced about the joint in normal walking. A cane can enlarge a supporting area and adjust the posture of the upper torso to be upright. An ischial weight-bearing brace is effective for conservative management of hip disorders by reducing a load to the joint (Shiba et al., 1998. Clinical Orthopaedics and Related Research 351, 149-157). Walking aids like a cane or brace have been conveniently used by the handicapped. Abnormal walking was simulated for each joint model. Dynamic effects of a cane and a brace on abnormal walking were examined by the multi-body walking model.

Ankle Joint↗
PubMed2000

Prognostic impact of cathepsin B and matrix metalloproteinase-9 in pulmonary adenocarcinomas by immunohistochemical study.

The expression of Cathepsin B (CB) and matrix metalloproteinase-9 (MMP-9) in extirpated tissues of adenocarcinomas in non-small cell lung cancer from 90 cases was investigated immunohistologically, and the correlations between the extent of the expression and the clinicopathological features were assessed for investigating the process of tumor metastasis. It is important to reveal the mechanisms of destruction of the basal membrane and infiltration of tumor cells at the primary lesion. Sections were obtained from 10%-formalin-fixed and paraffin-embedded tissues. They were reacted with an anti-human CB polyclonal antibody or an anti-human MMP-9 polyclonal antibody. Of 90 patients, 58 (64.4%) and 39 (48.3) cases were found to be positive for CB and MMP-9 expression, respectively. A significantly higher extent of the CB expression was observed in the tissues of patients who showed postoperative recurrence of the tumor (P = 0.013). Especially, a similar observation was obtained among early cases of T1N0 (P = 0.023). In contrast, no such tendency was demonstrated in the expression profile of MMP-9. Furthermore, the enzyme expressions were compared among different types of metastases. Patients with higher extents of CB expression tended to show significantly higher rates of hematogenous and intrapulmonary metastases (P = 0.023 and P = 0.010, respectively). However, there was no significant correlation between MMP-9 expression and the prognostic factor of the patients. Therefore, we suggested that evaluation of CB expression in the tumor tissue might be useful as a postoperative prognostic factor of pulmonary adenocarcinoma. Especially, early cancer of T1N0 cases showing higher expression of CB may need postoperative adjuvant chemotherapy.

Adenocarcinoma↗
PubMed2000

Proprioceptive afferents survive in the masseter muscle of trkC knockout mice.

Peripheral innervation patterns of proprioceptive afferents from dorsal root ganglia and the mesencephalic trigeminal nucleus were assessed in trkC-deficient mice using immunohistochemistry for protein gene product 9.5 and parvalbumin. In trkC knockout mice, spinal proprioceptive afferents were completely absent in the limb skeletal muscles, M. biceps femoris and M. gastrocnemius, as previously reported. In these same animals, however, proprioceptive afferents from mesencephalic trigeminal nucleus innervated masseter muscles and formed primary endings of muscle spindles. Three wild-type mice averaged 35.7 spindle profiles (range: 31-41), six heterozygotes averaged 32.3 spindles (range: 27-41), and four homozygotes averaged 32.8 spindles (range: 26-42). Parvalbumin and Nissl staining of the brain stem showed approximately 50% surviving mesencephalic trigeminal sensory neurons in trkC-deficient mice. TrkC-/- mice (n = 5) had 309.4 +/- 15.9 mesencephalic trigeminal sensory cells versus 616.5 +/- 26.3 the sensory cells in trkC+/+ mice (n = 4). These data indicate that while mesencephalic trigeminal sensory neurons are significantly reduced in number by trkC deletion, they are not completely absent. Furthermore, unlike their spinal counterparts, trigeminal proprioceptive afferents survive and give rise to stretch receptor complexes in masseter muscles of trkC knockout mice. This indicates that spinal and mesencephalic trigeminal proprioceptive afferents have different neurotrophin-supporting system during survival and differentiation. It is likely that one or more other neurotrophin receptors expressed in mesencephalic trigeminal proprioceptive neurons of trkC knockout mice compensate for the lack of normal neurotrophin-3 signaling through trkC.

Animals↗
PubMed2000

Selenium kinetics and changes in glutathione peroxidase activities in patients receiving long-term parenteral nutrition and effects of supplementation with selenite.

Selenium (Se) is an essential trace element in humans. Patients receiving long-term parenteral nutrition (PN) are at risk for Se deficiency. We investigated changes in Se levels and glutathione peroxidase (GSH-Px) activity in serum and tissue (red blood cells, RBC) in addition to urinary excretion of Se in patients receiving long-term PN with and without Se supplementation. In patients without Se supplementation, both Se levels and GSH-Px activity in serum decreased with duration of PN. The serum Se levels were below the lower limits of the control values in 19 of 33 patients (58%) who received PN for less than 1 mo. Conversely, RBC GSH-Px activity remained at a sufficient level in 9 of 12 patients (75%) who received PN for 3-6 mo. The RBC Se levels in all of these patients were lower than the control levels. Urinary Se concentrations were significantly correlated with serum Se concentrations by linear regression analysis (r = 0.707, P < 0.05). In patients with Se supplementation, urinary Se concentrations increased exponentially with increases in serum Se levels. These findings indicate that a time lag precedes the decrease in levels of serum Se, RBC Se, serum GSH-Px, and RBC GSH-Px in patients without Se supplementation and the increase in excretion of urinary Se in patients with Se supplementation. The monitoring of not only serum Se levels but also RBC GSH-Px activity and urinary Se levels is required for optimal Se supplementation during long-term PN.

Adolescent↗
PubMed2000

Comparison of the suppressive effects of soluble CR1 and C5a receptor antagonist in acute arthritis induced in rats by blocking of CD59.

We investigated the effects of suppression of complement activation at C3 level and inhibition of C5a on acute synovitis in rats. Acute synovitis was induced in Wistar rats by intra-articular (i.a.) injection into one knee of 0.3 mg of MoAb 6D1 (anti-rat CD59 antibody). In the treatment groups, soluble CR1 (sCR1) or C5a receptor (C5aR) antagonist was administered intra-articularly or intravenously and effects on the course of the acute synovitis were monitored. Synovitis induced by 6D1 was characterized by joint swelling, thickening of synovial tissue, cellular infiltration and deposition of membrane attack complex (MAC) on the synovial surface. Neither inflammatory change nor MAC deposition was found in rats which received an i.a. injection of sCR1 to suppress complement activity in the joint. Intra-articular injection of sCR1 did not reduce plasma complement activity. Intravenous administration of sCR1 suppressed plasma complement activity but had no effect on the course of the arthritis and synovitis with MAC deposition was observed. Neither i.a. nor i.v. injection of C5aR antagonist had any suppressive effects on inflammatory change or MAC deposition in synovium. The data show that inflammatory change induced by 6D1 was mediated by local complement activation and was not accompanied by systemic complement activation. C5a generation was not responsible for the observed inflammation, suggesting that other complement activation products, possibly MAC, mediate the inflammatory change observed in this model of acute synovitis in rats.

Acute Disease↗
PubMed2000

CD59 protects rat kidney from complement mediated injury in collaboration with crry.

BACKGROUND: As previously reported, the membrane-bound complement regulator at the C3 level (Crry/p65) is important in maintaining normal integrity of the kidney in rats. However, the role of a complement regulator at the C8/9 level (CD59) is not clear, especially when activation of complement occurs at the C3 level. The aim of this work was to elucidate the in vivo role of CD59 under C3 activating conditions. METHODS: Two monoclonal antibodies, 5I2 and 6D1, were used to suppress the function of Crry and CD59, respectively. In order to activate alternative the pathway of complement, the left kidney was perfused with 5I2 and/or 6D1 and was recirculated. RESULTS: In the kidneys perfused with 5I2 alone, deposition of C3 and membrane attack complex (MAC) was observed in the peritubular capillaries, vasa recta, and tubular basement membranes. Cast formation, tubular dilation and degeneration, and cellular infiltration were observed at days 1 and 4, and they recovered by day 7. Further suppression of CD59 by 6D1 significantly enhanced the deposition of MAC and worsened the already exacerbated tubulointerstitial injury. These effects of 6D1 were dose dependent. Perfusion with 6D1 alone did not induce histologic damage or MAC deposition in the tubulointerstitium. CONCLUSIONS: In rats, CD59 maintains normal integrity of the kidney in collaboration with Crry in rats against complement-mediated damage in vivo.

Animals↗
PubMed2000

Acute renal failure after a sea anemone sting.

A 27-year-old man suffering from severe swelling and pain in his right arm was referred to our hospital. He showed signs of acute renal failure (ARF) with severe dermatitis of his right arm. Three days before being admitted, he accidentally touched some kind of marine organism with his right hand while snorkeling in the Sulu Sea around Cebu Island. Within a few minutes, he was experiencing severe pain in his right hand. Then his right hand gradually became swollen. The marine creature responsible for this injury was thought to have been a sea anemone, which is a type of coelenterate. Histologic findings of a renal biopsy indicated that acute tubular necrosis (ATN) had caused ARF in this patient's case. Supportive therapies improved renal function of this patient, and steroid pulse therapy attenuated the severe skin discoloration. The ATN was thought to have been caused by the poison from a sea anemone because there were no other conceivable reasons for the patient's condition. This is the first time that a marine envenomation case has been reported in which the sting of a sea anemone has caused ATN without the failure of any other organs.

Acute Kidney Injury↗
PubMed2000

Biomechanical study of the resurfacing hip arthroplasty: finite element analysis of the femoral component.

Finite element analysis was performed using 3-dimensional models to examine the biomechanical characteristics of the femoral component in resurfacing hip arthroplasty. Stress concentration was observed in the cortical bone adjacent to the rim of the prosthesis. Stress shielding was observed in the anterosuperior regions on the cancellous bone cross-sections near the cup rim. These biomechanical characteristics may lead to complications such as femoral neck fractures in patients with osteopenic bone and long-term loosening.

Arthroplasty, Replacement, Hip↗