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Biomedical subjects

K Matsuno

Publications and source records attributed to K Matsuno.

At least 235 records · Page 13Linked to original sources
PubMed1991

Increased vascular permeability of Brucella abortus bacilli in the thymus of NZB/W F1 mice.

Various amounts of the bacterium, Brucella abortus (BA) were injected intravenously into autoimmune NZB/W F1 mice and non-autoimmune BDF1 mice and then the localization of BA in the thymus was traced using an immunohistochemical method at 30 min and 3 h after injection. The results showed that a greater amount of BA became consistently localized in the thymic parenchyma in a free form or in a phagocytized form in NZB/W F1 mice in comparison with BDF1 mice, indicating a marked increase of vascular permeability in the thymus of NZB/W F1 mice. The extravascular leakage of BA was clearly dose-dependent. The significance of invasion of bacterial antigens from the general circulation into the thymic parenchyma is discussed in relation to autoimmune states.

Animals↗
PubMed1991

[Intracellular Ca2+ mobilization and its regulation in platelet activation].

It has been generally accepted that platelets play etiological roles for the development of atherosclerosis and arterial thrombosis. Platelet activation may be dependent upon the cytosolic free Ca2+ concentration ([Ca2+]i), and regulated by PGI2 and endothelium-derived relaxing factor (EDRF) released by vascular endothelium. We have studied here the effect of endothelial cells (EC) on platelet activation and intracellular Ca2+ mobilization. Effluent of non-stimulated EC column inhibited thrombin-induced platelet aggregation and intracellular Ca2+ mobilization. An addition of this effluent to platelet suspension leaded to increase in intraplatelet cyclic AMP (cAMP) which was inhibited by the treatment of indomethacin to EC, suggesting that this effect was involved in PGI2 released by EC. On the other hand, effluent of thimerosal-stimulated EC column inhibited platelet aggregation and increase in [Ca2+]i stimulated with thrombin, and leaded to increase in intraplatelet cyclic GMP (cGMP). But the treatment of indomethacin to EC had no effect of this inhibition. The effect of thimerosal-stimulated EC was inhibited by the addition of 1-NG-monomethylarginine (NMA), EDRF/NO inhibitor, suggesting that EDRF released by thimerosal-stimulated EC produced an increase in cGMP and inhibited platelet activation. Although forskolin-induced in cAMP caused a marked prevention of inositol 1, 4, 5-trisphosphate (IP3) production stimulated with thrombin, 8-bromo cGMP and EDRF-induced increase in cGMP had no effect of IP3 production. An increase in cAMP and cGMP was considered to inhibit intracellular Ca2+ mobilization by different mechanisms in platelets.

Blood Platelets↗
PubMed1991

[A new advance in theory of blood coagulation and fibrinolysis and its practical application].

New trends in tests for coagulation and fibrinolysis and advances in diagnosis for the hypercoagulable state and utilization of immunological techniques such as various polyclonal and monoclonal antibodies are reported. We discussed (1) the new markers for hypercoagulable states, (2) differential diagnosis of disseminated intravascular coagulation (DIC) and abnormalities of coagulation in liver cirrhosis (LC), and (3) new markers for fibrinolysis and vascular function. Thrombin-antithrombin III complex (TAT) levels were higher in thrombotic diseases than in healthy controls. Therefore, TAT should be a good marker for hypercoagulation as fibrinopeptide A (FPA) and soluble fibrin monomer complex (SFMC). Measurement of TAT, plasma-alpha 2 plasmin inhibitor complex (PIC), and D dimer were useful for differential diagnosis of DIC and liver cirrhosis. t-PA-PAI complex correlated well with t-PA, but not with fibrinolytic parameters such as PIC. The t-PA-PAI complex may be a good marker for the function of the vascular endothelium.

Antithrombin III↗
PubMed1991

[Antibiotic sensitivity of bacteria isolated from patients at 6 hospitals in Osaka].

We examined MICs of 6 oral new quinolones and 4 oral cephems against bacteria isolated from patients at 6 hospitals in Osaka during the period from January to June in 1990, and the following results were obtained. 1. All species excluding Streptococcus pyogenes were more sensitive with less frequencies of resistance to new quinolones than to cephems. In new quinolones, tosufloxacin (TFLX) was the most active against Gram-positive cocci and ciprofloxacin (CPFX) and TFLX had the highest activities against Gram-negative rods. 2. Resistant (MIC of CPFX greater than or equal to 3.13 micrograms/ml) strains to new quinolones were observed at higher frequencies than 10% among Staphylococcus spp., Enterococcus faecalis, Citrobacter freundii, Morganella morganii, Providencia rettgeri, Serratia spp., Pseudomonas aeruginosa, Pseudomonas cepacia and Xanthomonas maltophilia. 3. The frequency of Staphylococcus aureus resistant to new quinolones isolated from in-patients or urine was significantly higher than that from out-patients or other sources. On the other hand, there was no significant difference in resistance frequencies of P. aeruginosa due to types of patients or sources. But, there were significant differences in frequencies of resistant organisms of either species to new quinolones among hospitals. 4. Twenty-seven strains (19.7%) of 137 S. aureus strains examined were methicillin-resistant, and they were similarly resistant to new quinolones also. Methicillin susceptible S. aureus were also similarly sensitive to new quinolones.

Anti-Bacterial Agents↗
PubMed1991

Information aspects of actomyosin complex.

Actomyosin complex as a representative case of cell motility exhibits an intricate interplay between the structure it maintains and the function it realizes. The correspondence between structure and function an actomyosin complex displays is a one-to-many type. Mechanochemical couplings underlying the energy transduction associated with the hydrolysis of ATP in the complex render the correspondence between the displacement of the medium and the force acting there a one-to-many type. Such a one-to-many correspondence between displacement and force makes the dynamic development informational in the sense that the prior indefiniteness turns into the posterior definiteness with the elapse of time. This characteristic exhibits sharp contrast to the time-honored one-to-one correspondence between displacement and force that is most common in mechanics, whether classical or quantal, in which no information is generated because of a forcible intrusion of exogenous detection of nonlocal character claiming an instantaneous bird's eye view of everything involved. Information generation is due intrinsically to the process of endogenous detection of local character, and the process has to be local because any physical signal propagates at a finite velocity. Actomyosin complex serves as a material example witnessing that detection of local character certainly generates information and leaves itself nonprogrammable.

Actomyosin↗
PubMed1991

Thymic nurse cells (TNC) in spontaneous thymoma BUF/Mna rats as a model to study their roles in T-cell development.

In order to elucidate possible roles of thymic nurse cells (TNC) we isolated them as lympho-epithelial cell complexes from spontaneous thymomas of BUF/Mna rats and characterized them using immuno- and enzyme-histochemical techniques. A remarkable increase in the number of TNC was seen at 8 months of age, immediately before or in accordance with the onset of thymomas. No structural abnormality in the TNC was detected by light-microscopy compared with those from normal control thymi. Phenotypically, the TNC per se were positive for major histocompatibility complex (MHC) class I, class II, cytokeratin and thymulin, but lacked macrophage markers, indicating their epithelial origin. They also expressed some of the markers for non-epithelial components, such as Thy-1, S100 and peanut agglutinin (PNA). The majority of intra-TNC cells were MHC class 1+, Thy-1+, CD5+, CD4+ CD8+ (double positive) and PNA+, but with some heterogeneity in their phenotype. The intra-TNC cells from thymomas revealed higher proliferation indices than those from control thymi, as assessed by 5-bromo-2'-deoxyuridine (BrdU)-uptake. It was also demonstrated for the first time that, not only in thymoma rats but also in normal control rats, about 15-30% of TNC enclosed macrophage populations within them. These results may suggest that the TNC in BUF/Mna thymomas represent typical TNC populations, but they are hyperactive particularly in their number and nursing capacity, resulting in the unusual increment of thymocytes in the thymomas. This animal model lends itself greatly to studies on the regulatory roles of TNC in T-cell development.

Aging↗
PubMed1990

Movement of vesicles in cytoplasmic streaming in plasmodium.

The moving velocities of vesicles in the cytoplasmic streaming of a slime mold were measured, in which all of the vesicles passing through a designated window were counted. Vesicles in the streaming are distributed in their moving velocities and the distribution itself varies with time. The mean velocity of vesicles and its standard deviation were found to exhibit a linear relationship, suggesting a possibility that vesicles in the cytoplasm would also be involved in force generation.

Cytoplasmic Streaming↗
PubMed1990

Fibroin gene promoter contains a cluster of homeodomain binding sites that interact with three silk gland factors.

By nuclease protection and mobility shift assays, we have shown that the 5' flanking sequence of the Bombyx mori fibroin gene, which is known to be required for a maximal level of transcription in vitro, contains five regions (A to E) that bind protein factors from the posterior silk gland extract. A silk gland-specific factor (SGF-1) and a ubiquitous factor (FBF-A1) were found to interact with the proximal A region, while the related B region can only bind SGF-1. The three distal regions (C, D and E) bind one posterior silk gland-specific factor (SGF-2) and two ubiquitous factors (SGF-3 and -4). SGF-1 might play an important role in the expression of silk protein genes because it also binds to a similar site in the sericin-1 gene and potential SGF-1 binding sites can be found in two other silk protein genes of Bombyx mori and the fibroin gene of Antheraea yamamai. The three distal regions for SGF-2, -3 and -4 contain ten base-pairs of A + T-rich repeats that resemble the consensus binding site (TCAATTAAAT) of a number of homeodomain proteins. The TAAT motif in the core of these regions is shown to be important for the binding of these three proteins and, as described elsewhere, two Drosophila homeodomain proteins, ZEN (zerknüllt) and EVE (even-skipped). Interestingly, SGF-3 appears to be a Bombyx octamer binding protein and may also be involved in the regulation of the sericin-1 gene. The possibility that the fibroin gene and other silk protein genes may be a group of target genes for some members of the homeobox gene family is discussed.

Animals↗
PubMed1990

Transcriptional stimulation via SC site of Bombyx sericin-1 gene through an interaction with a DNA binding protein SGF-3.

Three protein binding sites have been identified in the upstream region of the sericin-1 gene. Two of them, SA and SC sites, have been known as putative cis-acting elements. Using synthetic oligonucleotides of these binding sites, it was found that silk gland factor-1 (SGF-1) binds to the SA site, and silk gland factor-3 (SGF-3) binds to the SC site but not to a mutated SC site, SCM. Tissue distribution of the two factors was different. SGF-3 is present abundantly in the middle silk gland (MSG) where the sericin-1 gene is transcribed specifically but is also present in other cell types, though in a much less concentration. SGF-1 is observed very abundantly in the two parts of silk gland, MSG and posterior silk gland (PSG), but not in other cells. Templates containing multimerized SA or SC sites at -39 of the sericin-1 gene promoter were tested in MSG nuclear extracts. The SC multimer strongly activated transcription, while the mutant SCM multimer did not. The SA multimer also gave a slight stimulation of transcription. These results suggest that SGF-3 stimulates transcription through an interaction with the SC site, and SGF-1 does so weakly through the SA site.

Animals↗
PubMed1990

Multiple primary cancers in a case of chronic arsenic poisoning--an autopsy report.

This is an autopsy report of multiple primary cancers observed in a patient who had clinically been diagnosed as chronic arsenic poisoning. An 88-year-old man, non-smoker, had worked in an arsenic mine for 6 years from the age of 47. He had undergone operations for Bowen's disease and gastric cancer at ages 80 and 86, respectively. At autopsy, squamous cell carcinoma of the lung and a polypoid lesion in the piriform recess were found. Furthermore, microscopic examination revealed latent prostatic adenocarcinoma and oncocytoma in the kidney. The polypoid lesion of the piriform recess appeared to originate from the duct of the minor salivary gland in the pharynx, showing an adenoid cystic carcinoma-like pattern with squamous cell carcinoma in part. The cause of death was thought to be respiratory failure due to bronchopneumonia and pulmonary edema as well as hydrothorax, and chronic heart failure following ischemic heart disease. Bowen's disease was followed by four internal malignant tumors, even though the etiological relation between these cancers and arsenic is not clear.

Adenocarcinoma↗
PubMed1990

Localization in the rat spleen of carbon-laden macrophages introduced into the splenic artery: a subpopulation of macrophages entering the white pulp.

Heavily carbon-laden (HC) macrophages, largely derived from the red pulp of the donor spleen, were injected into the splenic artery of recipient rats. Immediately after injection, HC macrophages were found only in the marginal sinus and in the splenic cords. With time after injection, they appeared successively at the periphery of the white pulp, in the deeper white pulp, and finally in and near the germinal centers, suggesting migration of HC macrophages from the marginal sinus towards the germinal centers. The number of HC macrophages in and near the germinal centers reached a peak at 12 h. Most of the HC macrophages in the white pulp were spherical or ovoid in shape with a diameter of 7-11 microns in sections, having an eccentric round or oval nucleus often with a distinct nucleolus and a cap-like or horseshoe-like cytoplasm filled with carbon. When immunostained with monoclonal antibodies against rat macrophage subpopulations, more than 90% of HC macrophages in the white pulp were found to be ED1+2-3-. A population of the same type of macrophages, both in morphology and phenotype, were found in the red pulp of the donor spleen. They were different from the major residents, red pulp scavenger macrophages, which were ED1+2+3- and larger in size and irregular in shape. These results suggest the presence of a distinct subpopulation of macrophages which actively migrate into the splenic white pulp including the germinal centers. A discharge of transferred macrophages from the red pulp to the general circulation is also suggested.

Alkaline Phosphatase↗
PubMed1990

Dipyridamole potentiates the anti-aggregating effect of endothelium-derived relaxing factor.

One effector of the anti-aggregatory property of endothelium is thought to be endothelium-derived relaxing factor. The best characterized of these, nitric oxide, inhibits platelet aggregation by increasing cyclic GMP levels. The effects of nitric oxide and dipyridamole (a cyclic GMP phosphodiesterase inhibitor), alone and in combination, on in vitro platelet aggregation were evaluated. Dipyridamole had no effect per se on platelet aggregation but potentiated the inhibition of aggregation due to nitric oxide. This was concomitant with an increase in platelet cyclic GMP concentration. The author suggests an alternative mechanism for the clinical efficacy of dipyridamole as an antiplatelet agent.

Cyclic AMP↗
PubMed1990

Effect of ethylene glycol monomethyl ether and diethylene glycol monomethyl ether on hepatic metabolizing enzymes.

Glycol ethers have been extensively used in industry over the past 40-50 years. Numerous studies on the toxicity of glycol ethers have been performed, however, the effects of glycol ethers on the hepatic drug metabolizing enzymes are still unknown. We studied the changes of the putative metabolic enzymes, that is, the hepatic microsomal mixed function oxidase system and cytosolic alcohol dehydrogenase, by the oral administration of diEGME and EGME. Adult male Wistar rats were used. DiEGME was administered orally; 500, 1000, 2000 mg/kg for 1, 2, 5 or 20 days and EGME was 100, 300 mg/kg for 1, 2, 5 or 20 days. Decreases in liver weights were produced by highest doses of diEGME (2000 mg/kg body wt/day for 20 days) and EGME (300 mg/kg body wt/day for 20 days). DiEGME increased hepatic microsomal protein contents and induced cytochrome P-450, but not cytochrome b5 or NADPH-cytochrome c reductase. The activity of cytosolic ADH was not affected by diEGME administration. On the other hand, EGME did not change cytochrome P-450, cytochrome b5 or NADPH-cytochrome c reductase. The activity of cytosolic ADH was increased by repeated EGME treatment. Therefore it is suspected that the enzyme which takes part in the metabolism of diEGME is different from that of EGME, although diEGME is a structural homologue of EGME.

Administration, Oral↗
PubMed1990

Inhibition of tumor cell arrest in lungs by antimetastatic chitin heparinoid.

We have investigated the effect of sulfated chitin derivatives on the intravascular events in the metastatic cascade. 6-O-Sulfated carboxymethyl chitin (SCM-chitin III), as well as heparin, significantly inhibited the arrest of B16-BL6 cells in lungs after co-injection with radiolabeled tumor cells, but carboxymethylated chitin (CM-chitin) had no effect. Heparin showed a potent inhibitory effect on tumor cell-elicited platelet aggregation and on blood coagulation, which can subsequently enhance the survival, arrest and invasiveness of tumor cells, whereas SCM-chitin III showed much weaker properties. In contrast, SCM-chitin III was found to inhibit the adhesion of tumor cells to subendothelial matrix, while heparin did not. SCM-chitin III was still active in inhibiting experimental lung metastasis even in mice which had been pretreated with anti-asialo GM1 serum or carrageenan to eliminate NK cells or macrophages. Thus, these results suggest that SCM-chitin-mediated inhibition of tumor metastases is distinct from that by heparin and may be due to interference with tumor cell arrest in the capillaries and consequently to the inhibition of tumor cell adhesion to subendothelial matrix.

Animals↗
PubMed1990

[Studies on respiratory infections in primary care clinic (III). Distribution of bacteria isolated from patients with respiratory infections visiting 21 private clinics in the Tohoku District of Japan].

The bacteriology of the isolates from the throat swab and the sputum respectively of 2,539 patients with respiratory infections visiting 21 private clinics in Tohoku district of Japan during the period from January to April in 1989 was documented. Of the 2,539 patients, 1,694 had an acute upper respiratory infection, 609 had acute bronchitis, 46 had acute pneumonia, 84 had acute exacerbation of chronic respiratory infections and 106 had respiratory infections without diagnosis registered. 1887 (74.3%) strains of potential pathogens were recovered from 1507 (59.4%) of the 2539 cases. The rate of recovery of potential pathogens was very high in patients of the younger age. These patients had elevated body-temperature. There were statistically significant differences in recovery rate when classified by diagnosis, prefecture and the period of investigation. Of the 1,887 strains, 996 (52.8%) were gram-positive and 891 (47.2%) were gram-negative bacteria. The rate of recovery of gram-negative bacteria was high in patients who were less than 10 years old and more than 51 years old, in patients with pneumonia and chronic respiratory infections, and in patients with fever. Of the 1,887 strains, those which exceeded 100 were Staphylococcus aureus (481 strains), Haemophilus influenzae (340 strains), Streptococcus pneumoniae (329 strains), Streptococcus pyogenes (117 strains) and Acinetobacter spp. (100 strains). Species other than those mentioned above had less than 100 strains. In this group there were 39 strains of Branhamella catarrhalis, 32 strains of Escherichia coli, 97 strains of Klebsiella spp., 40 strains of Enterobacter spp., 25 strains of Serratia spp., 12 strains of Pseudomonas aeruginosa and 43 strains of Pseudomonas putida. There was a remarkable difference in recovery rate of each species when classified by diagnosis, age class, prefecture and the period of investigation, respectively. The above results indicated that gram-positive bacteria are more frequent than gram-negative bacteria, that enterobacteriaceae and glucose-non-fermentative gram-negative bacteria are only rarely found in primary care clinics, and that the bacteriology in primary care clinic is different from that of medical school-affiliated hospitals.

Adolescent↗
PubMed1990

[Studies on respiratory infections in primary care clinic (IV). Antibiotic sensitivity of bacteria isolated from patients with respiratory infections visiting 21 private clinics in the Tohoku District of Japan].

We determined the MICs of ampicillin, methicillin, cefaclor, cefixime, cefteram, ofloxacin and ciprofloxacin against a total of 1,448 strains from 11 species: 464 strains of Staphylococcus aureus, 306 strains of Streptococcus pneumoniae, 114 strains of Streptococcus pyogenes, 37 strains of Branhamella catarrhalis, 329 strains of Haemophilus influenzae, 32 strains of Escherichia coli, 66 strains of Klebsiella pneumoniae, 26 strains of Enterobacter cloacae, 20 strains of Serratia marcescens, 12 strains of Pseudomonas aeruginosa and 42 strains of Acinetobacter calcoaceticus, isolated from the throat swab and the sputum of 2,539 patients with respiratory infections who visited 21 private clinics in Tohoku district of Japan during the period from January to April in 1989. Ciprofloxacin and ofloxacin were more active against S. aureus, B. catarrhalis, P. aeruginosa and A. calcoaceticus than other antibiotics. Ampicillin and cefteram were more active against S. pneumoniae and S. pyogenes than other antibiotics. New-quinolones and cephems of new-generation were active against H. influenzae, E. coli, K. pneumoniae, E. cloacae and S. marcescens. Of 30 strains of S. aureus which were resistant (MIC greater than or equal to 12.5 micrograms/ml) to ampicillin, only one strain was resistant (MIC greater than or equal to 12.5 micrograms/ml) to methicillin. Twenty strains (6.5%) of S. pneumoniae and 49 strains (14.9%) of H. influenzae were resistant (MIC greater than or equal to 1.56 micrograms/ml) to ampicillin. Of 101 strains of H. influenzae of which their beta-lactamase activity was determined by Nitrocephin-method, 27 (26.7%) were beta-lactamase-positive strains. The above results indicated that MRSA is only rarely found in primary care clinics but the incidence of ampicillin-resistant H. influenzae in primary care clinics is almost the same as that of the intensive care clinic, i.e. medical school-affiliated hospitals. Therefore caution should be exercised as regards antibiotic resistance of the causative organism even in primary care clinics.

Ambulatory Care Facilities↗