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Biomedical subjects

M Takagi

Publications and source records attributed to M Takagi.

At least 505 records · Page 28Linked to original sources
PubMed1994

Collagenase in Sjögren's syndrome.

OBJECTIVE: To study collagenase production in labial salivary glands in patients with Sjögren's syndrome (SS). METHODS: Collagenases were localised in labial salivary glands by immunohistochemistry. Collagenase activity against triple helical type I collagen monomers in stimulated saliva was measured using sodium dodecyl sulphate polyacrylamide gel electrophoresis and laser densitometry; tissue inhibitor metalloproteinase (TIMP) was measured by enzyme linked immunosorbent assay. RESULTS: Cells containing collagenase of matrix metalloproteinase (MMP)-1 type were more frequent and more intensely staining in SS than in healthy glands. Only SS saliva contained functional enzyme (11.7 (6.8) x 10(-6) IU/1). Cells containing MMP-8 type neutrophil collagenase were not found in situ, which was in accordance with sialochemical findings/doxycycline inhibition studies. TIMP was found in both SS and normal saliva. CONCLUSIONS: Fibroblast, but not neutrophil type, collagenase is synthesised, secreted, and subsequently activated, but is not inhibited by TIMP in labial salivary glands or saliva in SS. Collagenase may destroy glandular and salivary duct tissue and perturb factors influencing the morphogenetic extracellular matrix.

Collagenases↗
PubMed1994

Re-examination of arousing and de-arousing effects of cigarette smoking.

An attempt was made to replicate arousing and de-arousing effects of cigarette smoking originally reported by Golding and Mangan. Changes in electrodermal activity, heart rate, and magnitude in the EEG alpha (7.5-11.5 Hz) and beta (13.5-20 Hz) bands were measured under conditions of both mild sensory isolation as well as stress induced by loud white-noise. Under both conditions, real smoking as well as sham smoking an unlit cigarette increased beta activity and the skin potential response. In contrast, only real smoking produced a significant increase in heart rate, decrease in alpha activity, and increase in skin potential. De-arousing effects reported by Golding and Mangan for white-noise stress were not replicated.

Adult↗
PubMed1994

Unusual angiographic changes in a dissecting aneurysm of the basilar artery: case report.

A patient with unusual angiographic changes of a dissecting aneurysm of the basilar artery is presented. Initial angiography and magnetic resonance imaging revealed a typical dissecting aneurysm. However, a follow-up study demonstrated a saccular aneurysmal dilatation of the proximal part of the dissection. The importance of the follow-up study, particularly in regard to the usefulness of magnetic resonance imaging and the pathogenesis of this change are discussed.

Aortic Dissection↗
PubMed1994

The deleterious effects of exogenous angiotensin I and angiotensin II on myocardial ischemia-reperfusion injury.

Angiotensin II is well known to have a cardiotoxic effects. However, it is still unclear whether exogenous angiotensin I or angiotensin II has a deleterious effect on myocardial ischemia-reperfusion injury. To examine this deleterious effects, we administered angiotensin I and angiotensin II to perfused hearts before ischemia, and measured creatine kinase (CK) release and cardiac function during subsequent reperfusion. Wistar Kyoto rats were used and the hearts were perfused by the Langendorff technique at a constant flow (10 ml/min). Seven hearts were perfused for 20 min and then subjected to 15 min of global ischemia (Control). In the experimental groups, during the 5 min before ischemia, we administered 100 ng/ml angiotensin I (Ang I; n = 9), 1 microgram/ml enalaprilat (ACEI; n = 5), both agents (ACEI + Ang I) (n = 6), or 10 ng/ml angiotensin II (Ang II; n = 6). The perfusates were then sampled to measure angiotensin II. After 15 min of ischemia, the hearts were reperfused with control perfusate. Throughout the 20 min of reperfusion, the effluent was collected to measure cumulative CK release. Angiotensin I increased coronary perfusion pressure (CPP) by 32 +/- 4 mmHg, however, the angiotension converting enzyme inhibitor inhibited the increase of CPP by angiotension I (11 +/- 1 mmHg) (p < 0.01). The contents of angiotensin II in the effluent in Ang I and Ang I + ACEI were 11.5 +/- 1.9 ng/ml and 4.0 +/- 0.5 ng/ml (p < 0.01). After 20 min of reperfusion, the left ventricular developed pressure was unchanged in all of the groups. CPP was also unchanged by ischemia in all of the groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiotensin I↗
PubMed1994

Isolation and characterization of two chitin synthase genes of Rhizopus oligosporus.

Two chitin synthase genes (chs1 and chs2) were isolated from Rhizopus oligosporus by plaque hybridization probed with the chitin synthase 2 gene of Saccharomyces cerevisiae. From their deduced amino acid sequences, they were both class II chitin synthases according to the classification proposed by Bowen et al. The expression of these genes was controlled differently in each stage of differentiation. It was suggested that the gene products of chs1 and chs2 function mainly in the hyphae growing stage but not in the late stage of spore formation. When each of these genes was expressed in S. cerevisiae, elevation of chitin synthase activity was observed in both cases.

Amino Acid Sequence↗
PubMed1994

Isolation and characterization of two chitin synthase genes from Aspergillus nidulans.

Two chitin synthase genes, designated chsA and chsB, were isolated from Aspergillus nidulans with the Saccharomyces cerevisiae CHS2 gene as the hybridization probe. Nucleotide sequencing showed that chsA and chsB encoded polypeptides consisting of 1013 and 916 amino acid residues, respectively; the hydropathy profiles of the enzymes were similar to those of other fungal chitin synthases. Northern analysis indicated that both genes were transcribed, suggesting that cellular chitin in A. nidulans is synthesized by at least two chitin synthases. For examination of the roles of the chitin synthase genes in cell growth, gene disruption experiments were done. The chsA disruptant grew as well as the wild-type strain, but the chsB disruptant had severe growth defects that could not be overcome by the addition of 1.2M sorbitol as an osmotic stabilizer. These findings suggested that chsB but not chsA is essential for hyphal growth.

Amino Acid Sequence↗
PubMed1994

Isolation of a chitin synthase gene (chsC) of Aspergillus nidulans.

We isolated a class I chitin synthase gene (chsC) from Aspergillus nidulans. Expression of this gene was confirmed by Northern analysis and by sequencing of the PCR-amplified DNA fragments from cDNA. chsC disruptants showed no difference of morphology in the asexual cycle and no difference of growth rate compared to a wild-type strain.

Amino Acid Sequence↗
PubMed1994

Characterization of Haemophilus paragallinarum isolated in the Philippines.

In 1989 and 1990, we isolated five strains of Haemophilus paragallinarum in the Philippines. Serological studies were done on three of these isolates. The results of haemagglutination, reactability to monoclonal antibodies and cross immunization with standard strains showed that they belonged to serotypes A, B and C respectively. This is the first report on the isolation of H. paragallinarum and on a related serological study in the Philippines.

Animals↗
PubMed1994

The Clostridium cellulovorans cellulosome.

The Clostridium cellulovorans cellulosome is comprised of a large, nonenzymatic scaffolding protein called the cellulose binding protein A (CbpA) and a number of endoglucanases/xylanases. The CbpA contains several functional domains, including a signal peptide, a cellulose binding domain (CBD), a hydrophilic domain (HLD) present four times, and a hydrophobic domain (HBD) present nine times. The functions of the domains were studied by the construction of minigenes containing the putative functional domains and by expression of the minigenes in Escherichia coli. The purified product of the CBD was able to bind to various crystalline forms of cellulose and chitin with a Kd of 1 microM. The binding capacity for CBD was a function of the crystallinity of the cellulose sample. Furthermore, the binding of CBD to Avicel was not inhibited by cellobiose or carboxymethylcellulose, suggesting that the CBD binding target was a three-dimensional structure found only in crystalline forms of cellulose. The HBD was tested for its ability to bind endoglucanases by an interaction Western as well as a sandwich enzyme immunoassay technique. The HBD was able to bind both EngB and EngD, indicating that the HBD contained an endoglucanase binding domain (EBD). Because there are nine EBD domains, it is possible that CbpA can bind up to nine endoglucanases. The role of the HLDs remains elusive. The data indicate that the cellulosome is a complex enzyme containing a scaffolding protein (CbpA) to which is attached a number of endoglucanase molecules. This arrangement allows the complex to bind and degrade crystalline cellulose, which resists degradation by the free forms of cellulosomal endoglucanases.

Amino Acids↗
PubMed1994

Extracellular matrix metalloproteinases around loose total hip prostheses.

We have explored the tissue localization of extracellular matrix metalloproteinases MMP-1 (fibroblast collagenase), MMP-2 (72-kDa gelatinase/Type IV collagenase), MMP-3 (stromelysin), MMP-8 (polymorphonuclear leukocyte collagenase) and MMP-9 (92-kDa gelatinase/Type IV collagenase) in the tissues around loose hip prostheses. The findings were compared with those in synovial tissues obtained from patients with a fractured femoral neck. MMP-type specific antisera were applied in the sensitive avidin-biotin-peroxidase complex methods. MMP-1 was found in monocyte/macrophages, fibroblasts, and vascular endothelial cells in both interface tissues between bone and acetabular components and the pseudocapsular tissues obtained from loosening of hip prostheses. In these tissues, MMP-8 was occasionally found, but only in polymorphonuclear leukocytes. Cells showing immunoreactivity to 72- and 92-kDa gelatinase/Type IV collagenase, MMP-2 and MMP-9, respectively, and stromelysin, MMP-3, were abundant in both interface and pseudocapsular tissues in loose hip prostheses. In contrast, in hip fractures, immunoreactivity to MMP-1, 2, 3, and 9 was weak and only observed in synovial tissues. Immunoreactivity to MMP-8 was confined to polymorphonuclear leukocytes attached to the synovial membrane or in the infiltrate around blood vessels in the subsynovial connective tissues. The finding of MMP-1, 2, 3, and 9 in the tissues around loose hip prostheses suggests that they play a role in the weakening of connective tissues, and this leads to loosening.

Aged↗
PubMed1994

[Bacteriological and clinical studies on cefozopran in pediatric field].

We carried out clinical studies on cefozopran (CZOP, SCE-2787). The results are summarized as follows. Treatment with CZOP was made in 17 cases of pediatric bacterial infections including 2 cases of purulent tonsillitis, 11 cases of acute pneumonia and 2 cases each of urinary tract infections and enteritis. Results obtained were excellent in 12 cases, good in 2 cases, fair in 2 cases and poor in 1 case. All of 9 isolated bacteria were eradicated by the treatment. As side effects and laboratory test results, rash was observed in one case and transient increase of platelets in one case, slight increase of eosinophil in 2 cases and transient elevation of GPT and GOT.GPT in one case.

Bacteria↗
PubMed1994

[Bacteriological and clinical studies of biapenem (L-627) in pediatric field].

We have carried out bacteriological and clinical studies on L-627. The results are summarized as follows. Treatment with L-627 was made in 14 cases of pediatric bacterial infections including 5 cases of pneumonia and 2 cases each of tonsillitis, urinary tract infection and one case each of colitis, and phlegmon. Results obtained were excellent in 11 cases, good in 2 cases and poor in one case. The bacteriological effect of L-627 was excellent, all causative organisms (Staphylococcus aureus one strain, Streptococcus pyogenes 2 strains, Streptococcus pneumoniae 3 strains, Escherichia coli 3 strains, Haemophilus influenzae one strain, Haemophilus parainfluenzae one strain) were eradicated. No significant side effects due to the drug were observed in any cases, except 2 cases each of elevated eosinophil counts and elevated platelet counts.

Bacteria↗
PubMed1994

[A case of polymyositis with ventricular tachycardia].

We reported a case of polymyositis with ventricular tachycardia. She had been suffering from proximal dominant muscle weakness and palpitation for 11 months. Holter EKG demonstrated 23 beats ventricular tachycardia. The noninvasive cardiac examination (Thalium cardiac scintigraphy, echocardiography, radionuclide ventriculography) demonstrated no abnormal findings. After initiation of steroid therapy, muscle strength and CK improved and ventricular tachycardia disappeared. Ventricular tachycardia is one of the important complications of polymyositis.

Adult↗
PubMed1994

Gelatinase/type IV collagenases in the loosening of total hip replacement endoprostheses.

Gelatinase/Type IV collagenases, namely, 72 kDa matrix metalloproteinase (MMP)-2 type and 92 kDa MMP-9 type, were analyzed to evaluate the role of extracellular matrix degradation in 17 cases of loosening of total hip endoprostheses. Zymographic and densitometric analyses revealed elevated production of MMP-2 and induction of MMP-9 in tissue extracts from both the interface tissues between bone and implants and the pseudocapsular tissues around the loose endoprostheses when compared with those of 8 control noninflammatory knee synovial tissues. The level of MMP-9 was higher in the interface tissues than in the pseudocapsular tissues. MMP-9 activity was not detected in the control samples. Although differences in the type of prosthetic fixation (cemented versus cementless) or the type of alloy (cobalt-chromium-molybdenum versus titanium-aluminum-vanadium) existed, they shared a similar potential to stimulate tissues to produce MMP-2 and MMP-9. These findings suggest a role for MMP-2 and MMP-9 type gelatinase/Type IV collagenases in the degradation of extracellular matrix of periprosthetic tissues, where they may cause weakening of the connective tissue bed and the loosening of total hip replacement endoprostheses. The pseudocapsular tissues could contribute to the loosening via the production and release of matrix metalloproteinases into the synovial fluid. Alternatively, induction of matrix metalloproteinases in such tissues may reflect remodeling of the pseudocapsular connective tissues.

Aged↗
PubMed1994

Ultrasonographic abdominal screening of atomic bomb-exposed subjects.

Abdominal ultrasonographic screening for cancer was performed in 6,001 Hiroshima and Nagasaki A-bomb exposed and comparison subjects, all members of the Adult Health Study of the Radiation Effects Research Foundation, formerly the Atomic Bomb Casualty Commission. This study yielded 20 cancers, including 7 hepatocellular, 3 gastric, 3 renal and 2 urinary bladder cancers; one cancer each of the ovary, pancreas, colon and ureter; and one cancer metastatic to the liver, whose primary was unknown. Seventeen of these 20 subjects manifested no symptoms or signs of their disease. A variety of additional tumors, unproven and probably benign, including uterine myomata, and other abnormalities were also detected. Abdominal ultrasonographic screening greatly assisted in the detection of cancers, most of which neither the patients nor their physicians were aware. In this screened fixed population sample the cancer detection rate was 0.33%, exceeding any such rates previously reported in the medical literature.

Abdominal Neoplasms↗
PubMed1993

Regulation of Bacillus subtilis senS by homologous regulatory regions of senS and the inducible cat gene.

We have identified a stem-and-loop region between the promoter and open reading frame of the Bacillus subtilis senS gene containing a 9 base sequence (TTTAGATAA) identical to a sequence found in a similar regulatory element of the inducible pC194 cat gene. A high copy number of this pC194 regulatory region repressed the expression of senS, indicating that the stem-and-loop region of the cat gene titrated a positive factor necessary for senS expression. These results suggest that factors with similar binding requirements control senS and cat expression. In addition, senS was found to be autoregulated.

Bacillus subtilis↗