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M Matsushita

Publications and source records attributed to M Matsushita.

At least 19 recordsLinked to original sources
PubMed1992

Activation of the classical complement pathway by mannose-binding protein in association with a novel C1s-like serine protease.

Serum mannose-binding protein (MBP) is a C-type lectin that binds to terminal mannose and N-acetylglucosamine moieties present on surfaces of certain pathogens and activates the classical complement pathway. In the present study, we describe the mechanism underlying the activation triggered by MBP. The human serum MBP fraction was obtained by sequential affinity chromatography on mannan-Sepharose, anti-IgM-Sepharose and anti-MBP-Sepharose in the presence of calcium ions. This fraction contained a C1s-like serine protease as assessed by C4 consumption. The C1s-like serine protease, designated MBP-associated serine protease (MASP), was separated from MBP by rechromatography on anti-MBP-Sepharose in the presence of ethylenediaminetetraacetic acid. MASP exhibited both C4- and C2-consuming activities. The molecular mass of MASP was estimated to be 83 kD with two polypeptides of heavy (66 kD) and light (L) (31 kD) chains linked by disulfide bonds. The serine residue responsible for protease activity is located on the L chain. Reconstitution experiments using MASP and MBP revealed that combination of the two components restores C4- and C2-activating capacity on mannan. Based on analyses of molecular size, antigenicity, and 11 NH2-terminal amino acid sequences of the L chain, we conclude that MASP is a novel protein different from C1r or C1s. Our findings are not in accord with a proposed mechanism by which MBP utilizes the C1r2-C1s2 complex to initiate the classical complement pathway.

Amino Acid Sequence↗
PubMed1992

[CT assessment of gallbladder opacification 12-24 hours after angiography].

After the injection of conventional contrast agents that are largely excreted in urine, gallbladder opacification is observed in patients with renal dysfunction. However, some reports have noted that gallbladder opacification on plain radiographs occurs frequently in patients without renal impairment after the intravenous administration of Ioxaglate, one of the new low-osmolality agents. We carried out CT examination 12-24 hours after angiography with various kinds of contrast media in 437 patients to examine the incidence of gallbladder opacification. The influence of hepatobiliary and renal function on the excretion of contrast medium is discussed. Gallbladder opacification was observed in more than 60% of the patients. This result indicates that gallbladder opacification is not a rare phenomenon, and is even common in delayed CT examinations of patients with normal renal function. The high frequency of gallbladder opacification was recognized not only in the renal dysfunction group but also in the normal liver function group. Gallbladder opacification in delayed CT examination shows that the hepatobiliary tract is important in the excretion of contrast medium.

Adolescent↗
PubMed1992

A new biological activity of the complement factor H: identification of the precursor of the major macrophage-chemotactic factor in delayed hypersensitivity reaction sites of guinea pigs.

The guinea pig complement factor H(FH) and the plasma precursor(PMCFS-1) of the major monocyte-chemotactic factor(MCFS-1) found in the skin site of delayed hypersensitivity reaction(DHR) induced in the guinea pigs were compared in the antigenicity and the function. Both anti-FH-IgG and anti-MCFS-1-IgG formed a single precipitation line against FH, PMCFS-1, MCFS-1 and guinea pig plasma, and these lines fused one another without any spur formation. The inhibition activity of FH for C3bBb was absorbed by anti-MCFS-1-F(ab')2 in a dose-dependent manner. PMCFS-1 inhibited C3bBb activity dose-dependently as FH. These results show that FH is identical to PMCFS-1 and imply that FH, converted to MCFS-1 plays as a monocyte-chemotactic factor in the site of DHR.

Animals↗
PubMed1992

[Image-transmission using 64 kbps-ISDN (Integrated Services Digital Network) and mini-PACS].

We carried out the image-transmission using 64kbps-ISDN between two image workstations (IWS) of mini-PACS installed at the Department of Radiology, Osaka Teishin Hospital and the Kashiwa Works, Hitachi Medical Corporation. The distance between Osaka and Kashiwa is about 600 km. The subtraction of two images before and after transmission revealed no change of the data of the image during transmission. For 1/2 compression image, the times of image-transmission of 256 x 256, 320 x 320 and 512 x 512 matrix were 9, 17 and 33 second, respectively. The efficiency of image-transmission was about 80%. Using ISDN, we can make an accurate, rapid and cheap image-transmission.

Computer Communication Networks↗
PubMed1992

Human mannose-binding protein is identical to a component of Ra-reactive factor.

Human Ra-reactive factor (RaRF) and mannose-binding protein (MBP) were isolated from sera by utilizing their affinity to Ra chemotype Salmonella typhimurium and yeast mannan, respectively. A predominant polypeptide of human RaRF with an Mr of 32 kDa (P32) has the same mobility as human MBP on SDS-PAGE gels. A monoclonal antibody against P32 of human RaRF, 3E7, was found to react not only with P32 but also with human MBP, as assessed by immunoblotting. In addition, 3E7 blocked the complement-activating capacity of human MBP. The NH2-terminal amino acid sequence of P32 of human RaRF was determined and found to coincide with that of human MBP. Based on these results, it is clear that human MBP is identical to a component of RaRF.

Antibodies, Monoclonal↗
PubMed1992

Trigeminocerebellar projections to the posterior lobe in the cat, as studied by anterograde transport of wheat germ agglutinin-horseradish peroxidase.

Cerebellar projections of the nucleus interpolaris and oralis of the spinal trigeminal nucleus were studied in the cat by anterograde transport of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP). Injections of WGA-HRP into these nuclei labeled many mossy fiber terminals mainly ipsilaterally in the rostral folium of lobule IX (IXa or IXa + b), the simple lobule, the anterior part (sublobule A) of the paramedian lobule and the posterior part of crus II. Labeled terminals were also seen in the anterior lobe, lobules VI and VII, the anterior part of crus I, and the paraflocculus dorsalis. Projection fields in the horizontal plane of lobules were reconstructed from a series of transverse sections through each folium of lobule IX, the paramedian lobule, and the posterior part of crus II on the ipsilateral side. In sublobule IXa + b, labeled terminals were distributed in five longitudinal areas extending along the apicobasal axis of the sublobule. These five areas were located in the apical two-thirds of the ipsilateral half of the sublobule. Labeled terminals were distributed in five longitudinal areas in sublobule A (the rostral part) of the paramedian lobule. In the posterior part of crus II, four aggregations of labeled terminals were present in cross sections through a lobule. They were distributed in the apicobasal extent of the lobules. The present study indicates that the projection fields of trigeminocerebellar fibers are longitudinally arranged along the apicobasal axis of the cerebellar lobules.

Animals↗
PubMed1992

Somatotopic termination of the spino-olivary fibers in the cat, studied with the wheat germ agglutinin-horseradish peroxidase technique.

Terminal sites of the spino-olivary fibers (SOFs) were examined by the anterograde transport of wheat germ agglutinin-horseradish peroxidase in the cat. The tracer was injected at various spinal cord levels from the first cervical to the caudal segments. The SOFs derived from the C1-T1 segments terminated medially in the caudal half (levels II-VIII of Brodal) of the medial accessory olive (MAO), which projects to the A zone of the cerebellar cortex, whereas the SOFs derived from the L6-S1 segments terminated laterally in the caudal half (levels I-VIII) of the MAO. No projections were found from the T2-L5 segments to the MAO. In the dorsal accessory olive (DAO), the SOFs terminated at levels III-XIV; the DAO projects to the B zone and the C1 and C3 zones of the cerebellar cortex. The SOFs derived from the C1-C4 segments terminated in the most medial part of the DAO (levels III-XIV), followed laterally by those from the C5-T1 segments. Further laterally, the SOFs derived from the T2-L5 and the L6-S1 segments terminated in the mediolateral order at levels V-XIV. The SOFs from the L6-S1 segments occupied the most lateral part of the DAO. The present study demonstrates that there is a distinct somatotopic termination of the SOFs in the mediolateral order in the caudal MAO and the DAO.

Animals↗
PubMed1992

Effect of long-term insulin deficiency and insulin treatment on the composition of triglyceride-rich lipoproteins and triglyceride turnover in rats.

The effect of long-term (4 months) insulin deficiency on triglyceride turnover was examined using Triton WR1339 in rats. Triglyceride secretion rate was estimated in rats 2 weeks and 4 months after induction of diabetes with 40 mg/kg of streptozotocin. By the second week diabetic rats showed prominent hyperglycemia and the plasma insulin level was very low. In spite of a lower triglyceride secretion rate compared to non-diabetic control rats, diabetic rats showed normotriglyceridemia. Thus, the estimated fractional catabolic rate for plasma triglyceride was decreased in the diabetic rats of 2 weeks duration. By the fourth month diabetic rats still showed a suppressed triglyceride secretion rate but plasma triglyceride was markedly higher than in the non-diabetic control rats. Therefore, their estimated fractional catabolic rate for plasma triglyceride was severely suppressed. They also showed hyperglycemia and hypercholesterolemia. The triglyceride-rich lipoprotein particles obtained after Triton injection in long-term diabetic rats were significantly cholesterol-enriched and triglyceride-depleted compared to control rats. These changes were already present in 2-week diabetic rats but the magnitude was significantly smaller that those in long-term diabetic rats. All of these abnormalities (including triglyceride turnover and the particle composition) were almost normalized by 2 weeks of insulin treatment (6 units/day). Thus, it was concluded from the present data that duration of insulin deficiency is an important determinant of triglyceride removal rate from the circulation in rats. Further modification of lipid composition of triglyceride-rich lipoprotein particles by long-term insulin-deficiency could be one of the reasons for this removal defect.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Effect of mild diabetes and dietary fructose on very-low-density lipoprotein triglyceride turnover in rats.

Very-low-density lipoprotein (VLDL) triglyceride turnover was examined in mildly streptozotocin (25 mg/kg)-diabetic rats, using Triton WR1339. Diabetic rats fed standard rat chow showed mild hyperglycemia and suppressed levels of plasma insulin. Their triglyceride secretion was significantly suppressed despite an elevated level of plasma free fatty acids. However, the plasma triglyceride level of these diabetic rats was significantly elevated compared with nondiabetic controls. This suggested that the removal of triglyceride from the circulation, as well as its entry into the circulation, was impaired in mildly insulin-deficient rats. Glucose or fructose supplementation (10% in drinking water for 14 days) significantly increased the triglyceride secretion rate of diabetic rats. Especially, fructose supplementation increased plasma insulin to normal levels, but resulted in markedly elevated plasma triglyceride levels (three times higher than glucose-supplemented or chow-fed diabetic rats) despite similar triglyceride secretion rates between the two types of sugar-supplemented diabetic rat groups. This suggested an impairment of triglyceride removal by dietary fructose. The result obtained from chow-fed diabetic rats indicates that mild but significant insulin deficiency resulted in mild hypertriglyceridemia, linked to impaired triglyceride removal rather than to an overproduction of VLDL-triglyceride, despite elevated levels of plasma free fatty acids. Furthermore, fructose feeding induced prominent hypertriglyceridemia not only by stimulating triglyceride secretion, but also by suppressing triglyceride removal from the circulation of mildly diabetic rats.

Animals↗
PubMed1992

Biodegradable pericardial implants for bladder augmentation: a 2.5-year study in dogs.

Bladder augmentation using biodegradable pericardial tissue was evaluated in canine bladders. Acetic acid and acetic anhydride treated pericardial tissue grafts were stored in 75% ethanol for 18 to 27 months before implant. Ten dogs weighing 20 to 25 kg. were subjected to a 50% partial cystectomy. After careful separation of the mucosa, bladder muscle and adventitial layers a pericardial graft volumetrically equivalent to the portion of the bladder removed was sutured to the bladder remnant in 2 layers. In 1 control dog the bladder was opened, 50% of the bladder was removed and the bladder was closed primarily. In another control dog the excised bladder was replaced with fresh chemically treated patch material that was never subjected to ethanol storage. Excretory urography and cystography were performed on all dogs. Urodynamics with filling pressures and bladder volumes measured before and after the operation at intervals of up to 36 months confirmed that adequate bladder capacity was achieved. There were no operative complications. Postmortem histological evaluations revealed a smooth epithelialized inner surface with no traces of any surface irregularities or suture lines. The bladder apex showed an intact epithelium and the absence of a smooth muscle layer. The biodegradable acetylated tissue provides an intact structural reservoir for urine and serves as a template for epithelial regeneration. This permits volumetric bladder enlargement while the graft is progressively reabsorbed with time.

Animals↗
PubMed1992

Effect of probucol on recovery from streptozotocin diabetes in rats.

The present study was conducted to see the effect of probucol on streptozotocin diabetes in rats. After 2 weeks of a 1% probucol diet, 35 or 50 mg/kg of streptozotocin were intravenously injected into male Wistar rats. All the rats became diabetic 2 days after treatment. Thereafter, in order to see the effect of probucol on spontaneous recovery from streptozotocin diabetes, 25 mg/kg of streptozotocin was injected into rats after two weeks of probucol diet and the diet was continued for additional two weeks. All the rats with a standard diet (group CS, n = 13) and 12 of 13 rats with probucol diet (group PS) became diabetic 2 days after streptozotocin injection. One rate from group PS did not develop diabetes. Two weeks after injection, only 4 of 13 rats in groups CS showed recovery, while 11 of 12 rats in group PS showed recovery from streptozotocin diabetes (p less than 0.05). The average blood glucose levels in group PS were significantly lower than group CS (10.5 +/- 4.6 vs 18.5 +/- 0.6 mM, p less than 0.05). In addition, the pancreatic insulin content of group PS was 8 times greater than that of group CS (0.75 +/- 0.24 vs 0.09 +/- 0.03 mmol/pancreas, p less than 0.01). Thus, the in vivo diabetogenic action of streptozotocin could not be reduced by pretreatment with probucol. However, recovery from streptozotocin diabetes was induced by subsequent treatment with probucol. The precise mechanisms for this phenomenon were not known; but the present findings suggest the protective effect of probucol on beta-cell damage induced by small dose of streptozotocin.

Animals↗
PubMed1992

Temporal lobe CO2 vasoreactivity in patients with complex partial seizures.

The topography of CO2 vasoreactivity during hyperventilation in 8 patients with complex partial seizure (CPS) was visualized using the regional cerebral blood flow (rCBF) as measured by H(2)15O-PET (positron emission tomography) and compared with that of 10 normal volunteers. In the normal volunteers, the vascular response to CO2 (VrCO2 = delta CBF%/delta PaCO2) in the temporal lobe was 2.46 +/- 0.56 (%/mmHg). In the patients with CPS, VrCO2 in the temporal lobe of the affected side was 2.08 +/- 0.40 (%/mmHg), while VrCO2 on the contralateral side was 2.30 +/- 0.46 (%/mmHg). There was a significant difference in VrCO2 between the affected side of the temporal lobes and the temporal lobes of the normal volunteers. Furthermore, there was a tendency for VrCO2 to be lower in the affected than in the contralateral side of the temporal lobe in patients with CPS. As CO2 is the main regulator of CBF, this impaired vasoreactivity may reflect the brain dysfunction in the seizure focus and adjacent areas.

Adolescent↗
PubMed1992

Self-similar colony morphogenesis by gram-negative rods as the experimental model of fractal growth by a cell population.

The ability to form a fractal colony was shown to be common among several species of the family Enterobacteriaceae. Bacterial spreading growth in a two-dimensional field of nutrient concentration was indicated to be important for this experimental self-similar morphogenesis. As a basic analogy, the diffusion-limited aggregation model was suggested. Fractal dimensions of colonies were mostly in the range of values from 1.7 to 1.8, similar to those of the two-dimensional diffusion-limited aggregation model. Bacterial characteristics and culture conditions inducing changes in fractal patterns and growth rates were identified. The contribution of the bacterial multicellular nature to fractal morphogenesis is discussed.

Glucose↗
PubMed1992

CT of gastric carcinoma: preliminary results with a new scanning technique.

Usefulness of computed tomography (CT) for the demonstration of gastric carcinoma was evaluated in 250 cases with surgical proof of diagnosis: advanced gastric carcinoma (n = 193), early gastric carcinoma (n = 47), gastric submucosal tumor (n = 8), gastric polyp (n = 1), and benign gastric ulcer (n = 1). CT was performed on prone patients after 400-600 mL of water was orally administered and a 100-mL bolus of nonionic contrast material was injected. Water provided optimal distention and satisfactory contrast to depict the normal gastric wall. Prone positioning allowed visualization of the whole gastric wall except for the fundus and prevented artifacts caused by gas during supine imaging. CT demonstrated gastric tumor as a thickened or abnormally enhanced gastric wall in 95% of advanced carcinomas, 93% of elevated early carcinomas, and 18% of depressed early carcinomas. The authors believe that CT performed with this method is useful and that it should be used in addition to barium and endoscopic studies before surgery is planned.

Carcinoma↗
PubMed1992

[Endosonographic diagnosis of metastatic tumors in the recto-uterine or recto-vesical space by transrectal scan].

A 6-year experience of transrectal ultrasonography (TRUS) in 75 patients with advanced gastrointestinal cancers was reviewed regarding the diagnostic yield of metastatic extrarectal tumors. A diagnostic capability of TRUS (a sensitivity of 82.9%, a specificity of 97.5% and an accuracy of 90.7%) was statistically superior to that of digital rectal examination (a sensitivity of 62.9%, a specificity of 75% and an accuracy of 69.3%). However, TRUS could hardly correctly diagnose a miliary type of extrarectal tumors in contrast to nodular and thickened types. TRUS also had an advantage over conventional ultrasonography in detecting a small amount of ascites with a sensitivity of 75%, a specificity of 93% and an accuracy of 86.6%. Patients with positive signs of extrarectal tumors or ascites on TRUS survived significantly shorter than those with negative signs. TRUS renders a convenient means in the objective diagnosis of peritoneal carcinomatosis, and predicts patient's prognosis.

Adult↗