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Biomedical subjects

T Fujiwara

Publications and source records attributed to T Fujiwara.

At least 865 records · Page 48Linked to original sources
PubMed1991

Oral passive immunization against dental caries in rats by use of hen egg yolk antibodies specific for cell-associated glucosyltransferase of Streptococcus mutans.

The effect of polyclonal egg yolk immunoglobulin G antibodies (yIgG) raised against whole cells, cell-free (CF) glucosyltransferase (GTase), or cell-associated (CA) GTase of serotype c Streptococcus mutans was examined in terms of in vitro inhibition of virulence-related factors of S. mutans and protection of S. mutans-infected rats against the development of dental caries. Hens (18 weeks old) were immunized with formalin-treated whole cells, purified CF-GTase, or CA-GTase together with Freund's complete adjuvant. In addition, yIgG to surface protein antigen was used in some in vitro experiments for comparison with other antibodies. yIgG was purified by ammonium sulfate precipitation followed by DEAE-Sephacel column chromatography or fractional precipitation with ethanol. Purified yIgG was found to be a 220-kDa protein, which was dissociated into heavy and light chains upon addition of 2-mercaptoethanol. yIgG to whole cells and surface protein antigen gave a heavy aggregation of S. mutans organisms, while yIgG to CF- and CA-GTase specifically inhibited the enzymatic activity of the respective GTase. yIgG to CA-GTase and whole cells was found to clearly suppress the adherence of S. mutans cells to a glass surface. Specific-pathogen-free Sprague-Dawley rats that had been infected heavily and repeatedly with S. mutans and fed diet no. 2000 developed severe dental caries, while rats fed diet 2000 containing greater than or equal to 0.1% yIgG to CA-GTase showed a statistically significant reduction in dental plaque accumulation and caries development. Administration of yIgG to CF-GTase and whole cells failed to protect against caries. These results clearly suggest that yIgG to S. mutants CA-GTase specifically inhibited a virulence factor of this organism, i.e., insoluble glucan-synthesizing CA-GTase, resulting in a significant reduction in the development of dental caries.

Administration, Oral↗
PubMed1991

Dental caries induction in hyposalivated rats.

The effects of hyposalivation on the induction of dental caries and on the oral microflora were examined in SPF Sprague-Dawley rats with or without inoculation of oral streptococci. Significant dental caries was induced in hyposalivated rats, irrespective of the infection with oral streptococci including Streptococcus mutans. In addition, bacteriological analyses demonstrated that the total number of lactobacilli increased significantly at the expense of the inoculated streptococci. These findings suggest that opportunistic infections may be induced in the oral cavity of hyposalivated rats and some acidogenic microorganisms including lactobacilli may promote the induction of dental caries.

Animals↗
PubMed1991

Trehalulose does not induce dental caries in rats infected with mutans streptococci.

The effects of trehalulose, a structural isomer of sucrose, and a syrup (TP syrup) rich in trehalulose and palatinose on caries development were examined in specific pathogen-free Sprague-Dawley rats. Streptococcus mutans MT8148R and Streptococcus sobrinus 6715 fermented the syrup which resulted in acid production, while both strains were found not to utilize trehalulose. Furthermore, trehalulose did not serve as a substrate for glucosyltransferases of these mutans streptococci to synthesize water-insoluble glucan, and it inhibited the sucrose-dependent adherence of mutans streptococci to a glass surface. Although trehalulose induced no significant dental caries in specific pathogen-free rats infected with either MT8148R or 6715, TP syrup was found to induce significant but low dental caries. Furthermore, replacement of the dietary sucrose content with trehalulose resulted in a significant reduction of caries development in rats infected with strain 6715.

Animals↗
PubMed1991

Light and electron microscopic localization of brain natriuretic peptide in relation to atrial natriuretic peptide in porcine atrium. Immunohistocytochemical study using specific monoclonal antibodies.

BACKGROUND: Although first isolated from the porcine brain, brain natriuretic peptide (BNP) is also found in the heart, particularly in the atria. METHODS AND RESULTS: We examined the immunocytochemical localization of BNP in relation to atrial natriuretic peptide (ANP) in five porcine atria using highly specific monoclonal antibodies. With the use of an indirect immunoperoxidase method, serial sections examined by light microscopy showed foci of multihormonal myocytes containing both ANP and BNP localized in the subendocardium. Monohormonal myocytes containing ANP only were observed in the subepicardium and part of the subendocardium. The staining intensity of ANP and BNP showed a transmural gradient from the subendocardium to the subepicardium. At the electron microscopic level, double immunocytochemistry using a two-face immunogold-staining method revealed two types of granules: Type 1 is a monohormonal granule containing ANP alone, and type 2 is a multihormonal granule containing both ANP and BNP. Although most atrial myocytes contained both, type 1 granules were frequently observed in the epicardial side, and type 2 granules were frequently observed in the endocardial side. We observed a few type 2 granules even in the light microscopically monohormonal myocytes. CONCLUSIONS: These data suggest that the atrial myocyte population comprises single, multipotential cells able to synthesize both natriuretic peptides in varying proportions. The atrial transmural gradient of BNP and ANP may be related to responses to wall stress.

Animals↗
PubMed1991

Formation of an antibacterial metabolite from a new macrolide compound 23-O-benzyl-5-mycaminosyl-tylonolide (TMC-101), by a hepatic microsomal drug-metabolizing enzyme system.

Upon incubation of 23-O-benzyl-5-mycaminosyl-tylonolide (TMC-101) with liver microsomes in the presence of an nicotinamide adenine dinucleotide phosphate-generating system, at least four metabolites were formed: two of them were also formed by an enzyme(s) in rat serum. One of the metabolites formed by liver microsomes possessed antibacterial activity comparable to TMC-101 as examined by bioautography using Micrococcus luteus ATCC 9341 as a tester strain. Incubation of TMC-101 with rat serum degraded most of the parent compound and did not form the active metabolite. The capacity of liver microsomes to produce the active metabolite was increased by pretreatment of rats with 3-methylcholanthrene, phenobarbital and polychlorinated biphenyl. The metabolite with the antibacterial activity was estimated not to be formed by the N-demethylation of TMC-101, and was chemically unstable.

Animals↗
PubMed1991

Maximum venous outflow and development of deep vein thrombosis.

To evaluate the relationship between maximum venous outflow (MVO) of the leg and development of deep vein thrombosis (DVT), venous occlusion plethysmography (VOP) using a Mercury strain gauge was carried out in 56 unilateral DVT patients. The data from these patients were compared with those obtained from several control groups. Then, the relationship between plethysmographic and 9 clinical variables was statistically analysed in the normal legs of these patients. The mean MVO of the normal legs of these patients was significantly higher than that of the affected legs, but it was significantly lower than those of normal controls and patients with mild congestive heart disease. However, it was similar to those in patients with lymphedema and obese men. A decrease in the MVO of the normal legs of these patients was noted in older females with femoral vein obstruction of the left leg, with a shorter number of days from the onset of symptoms or with higher values for the obesity index and calf circumference. Significant correlations between the MVO and the obesity index (r = -0.59), venous capacitance (VC, r = 0.49) and the number of days from the onset of symptoms (r = 0.40) were found in the normal right legs of these patients (n = 40). In the normal left legs (n = 16), on the other hand, significant correlations were found between the MVO and the VC (r = 0.65) and the MVO and age (r = -0.65).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

V-src genes in two cell lines of so-called RSV-transformed human cells are defective and inactive.

Trial of Rous sarcoma virus (RSV) induction by cell fusion with chick embryo cells (CEC) and wing web test from so-called RSV-transformed human cells, KC and RSb cells, was unsuccessful. The loss of RSV inducibility was also confirmed by DNA transfection method. Southern blot and northern blot hybridization of DNA and RNA from those cells with the v-src probe revealed that the v-src genes in those cells were defective and not expressed. On the other hand, the v-src gene in RSV-transformed mouse and rat cells was complete and transforming virus was inducible from them.

Avian Sarcoma Viruses↗
PubMed1991

Treatment of malignant glioma with high dose intra-arterial ACNU and autologous bone marrow transplantation--case report.

A 44-year-old female with malignant astrocytoma received subtotal removal and high dose (200 mg/m2) intra-arterial 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2- chloroethyl)-3-nitrosourea hydrochloride (ACNU) with autologous bone marrow transplantation. Tumor remission with minimal bone marrow suppression was achieved. However, she developed severe encephalopathy and computed tomographic scans revealed a low-density area at the ACNU delivery site. She received glycerol solution to treat the brain edema and recovered completely from the encephalopathy. Intra-arterial ACNU exceeding 200 mg/m2 possibly causes neurotoxicity.

Adult↗
PubMed1991

An improved fixation method for transmission electron microscopy for the histological study of the lens.

An improved fixation technique for transmission electron microscopic observation that enables good fixation of all areas of the rat lens was devised. Immersion fixation with 0.1 M phosphate-buffered 1.25% glutaraldehyde at 4 degrees C for 12 hours followed by postosmication produced good results for all areas of the lens--anterior, equatorial, and posterior zones. The technique was particularly suitable for maintenance of the shape of the lens since practically no irregularity, vacuolar degeneration, or expansion of the intercellular spaces was noted. This technique, which requires only a relatively short time, was also useful for the detection of early ultrastructural changes associated with cataract in spontaneously diabetic WBN/Kob rats. We anticipate that our procedure will be widely applied.

Animals↗
PubMed1991

Synthesis of the trisaccharide-protein conjugate of the phenolic glycolipid of Mycobacterium tuberculosis for the serodiagnosis of tuberculosis.

The trisaccharide segment of the phenolic glycolipid (PGL) of Mycobacterium tuberculosis, 2-O-methyl-3-O-[3-O-(2,3,4-tri-O-methyl-alpha-L-fucopyranosyl)-alpha-L- rhamnopyranosyl]-alpha-L-rhamnopyranose, was synthesized in the form of the p-(2-methoxycarbonylethyl)phenyl glycoside by a stepwise condensation. 2,4-Di-O-benzyl-3-O-acetyl-alpha-L-rhamnopyranosyl chloride was coupled to p-(2-methoxycarbonylethyl)phenyl 4-O-benzyl-2-O-methyl-alpha-L-rhamnopyranoside in the presence of silver triflate, and 2,3,4-tri-O-methyl-alpha-L-rhamnopyranosyl chloride was then coupled to the deacetylated disaccharide by the same procedure. The trisaccharide was deblocked and coupled to BSA, giving the neoglycoconjugate TB-NT-P-BSA. TB-NT-P-BSA showed its possibility as a useful tool for the serodiagnosis of tuberculosis.

Antigens, Bacterial↗
PubMed1991

[Small sized non-small cell lung cancer in advanced stage].

Eighteen cases of non-small cell, small sized advanced lung cancer, out of 362 operated cases for 6 years excluding 7 cases of small cell lung cancer, 60 of preoperative treated and 27 of inoperable cases, were discussed. A small sized tumor was defined as a tumor within 8,000 mm3 in its volume, calculated by multipling three lengths measured on the resected specimens. There were fourteen cases with stage 3 and 4 (A), and four cases with N1 disease (B). In group A, three cases of twelve with N2 diseases showed the tiny skipping lesion in the mediastinum with negative regional nodes. Remaining two had a lesion of dissemination and pulmonary metastasis. In group B, they showed unusual way of N1 spread, in which two of them with left upper lobectomy had metastatic lymph nodes on the non-bearing lobe, the lower lobe, and other two cases took regional lymph nodes metastasis without invasive growth of the main tumor. Predominant histologic type was adenocarcinoma, but the subtype and the differentiation of it were not specific. The level of CEA was low below 5 ng/dl in most of them except three cases, in which it suggested massive positive nodes and pulmonary metastasis. Seven patients died of the disease in two years. Remainders are alive, 4 with and 7 free from the tumor with the longest period of 3 years and a half. N2 diseases of small sized tumor were found in the cases with the volume of 3 cm3 and more at almost same ratio.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Endogenous opiate response to pain in rheumatoid arthritis and cortical and subcortical response to pain in normal volunteers using positron emission tomography.

Identification of the main areas in the brain that respond specifically to the "suffering" components of pain has been achieved by using serial dynamic measurements of blood flow as an index of synaptic activity. Specific response to a repeated painful thermal stimulus as compared to a non-painful thermal stimulus in normal male volunteers identified the anterior cingulate cortex and the thalamus contralateral to the side of stimulation as the main sites of significant response. It was concluded that it was these areas where pain was likely to be experienced. Changes in opioid receptor binding in the brain was measured using 11C-diprenorphine and positron emission tomography in three patients with rheumatoid arthritis. In the two patients with active rheumatoid arthritis substantial changes in opioid receptor binding in the brain are described. The significance of these findings are discussed.

Arthritis, Rheumatoid↗
PubMed1991

Changes in polypeptide-specific factor VIII antigen levels during whole blood clotting.

The time-course of factor VIII (FVIII) proteolysis during whole blood coagulation was monitored using polypeptide-specific enzyme-linked immunosorbent assays (ELISAs) developed with monoclonal antibodies to FVIII. Such assays of whole blood from normal subjects revealed that, within 30 min after coagulation had started, levels of the amino-terminal region of FVIII light chain and in the middle region of FVIII heavy chain had decreased to baseline in parallel with factor VIII procoagulant activity, but that levels of the 70 kDa thrombin digest decreased more slowly, with 75 U/dl of FVIII antigen (FVIII:Ag) remaining even after 2 h. Similar analysis of the blood of a patient with congenital hypoprothrombinemia indicated a lag phase of 20 min before proteolysis started. No significant change was observed until 1 h after calcium chloride was added to prothrombin-depleted plasma. On the other hand, in the presence of tissue thromboplastin, levels of FVIII:Ag in all ELISAs decreased rapidly. These results indicate a requirement for thrombin generation in the proteolysis of FVIII during the process of whole blood clotting.

Blood Coagulation↗
PubMed1991

[Expression of atrial natriuretic polypeptide in ventricles of heart with hypertrophic cardiomyopathy: an immunohistochemical study of endomyocardial specimens].

To investigate the ventricular expression of atrial natriuretic polypeptide (ANP) in human hypertrophic heart, we conducted an immunohistochemical study using endomyocardial biopsy specimens obtained from the right side of the interventricular septum (RVB), left ventricular free wall (LVB), or both of 39 patients with hypertrophic cardiomyopathy (HCM), and 9 control subjects without hypertrophy. No HCM patients had apparent congestive heart failure. ANP was not present in control subjects' RVB or LVB specimens, but was found in HCM patients', showing its characteristic distribution patterns (RVB > LVB, p < 0.05); it was present in 15 of 36 RVB (42%) and 2 of 25 LVB (8%). No clinical data, including echocardiographic, hemodynamic and angiographic data, were directly related to ventricular ANP expression in HCM. According to histological data, however, ANP-present RVB specimens of HCM had larger myocytes, severer fibrosis and myofiber disarray than the specimens without ANP. This indicates that a failing state may not be a prerequisite for ANP expression in human hypertrophic ventricles, but that ventricular ANP expression may occur concomitantly with myocyte hypertrophy as an adaptive response to focal stress due to "histological overloads" such as disarray and fibrosis in HCM, which may be reflected in the characteristic distribution patterns of intraventricular ANP.

Atrial Natriuretic Factor↗