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T Fujiwara

Publications and source records attributed to T Fujiwara.

At least 271 records · Page 15Linked to original sources
PubMed1999

Targeted salivary gland immunization with plasmid DNA elicits specific salivary immunoglobulin A and G antibodies and serum immunoglobulin G antibodies in mice.

For the development of vaccines against oral and pharyngeal pathogens invading the mucosal epithelia, both secretory and serum immunoglobulin A (IgA) and IgG antibodies and cytotoxic T lymphocytes (CTL) have been induced. We used a novel approach, targeted salivary gland (TSG) immunization, using plasmid pcDNA3/fimA, coding for Porphyromonas gingivalis fimbriae. Expression of subunit protein, fimbrillin, was observed in eukaryotic cells growing in vitro following transfection with pcDNA3/fimA. In this study, we obtained good humoral and cell-mediated immune responses in BALB/c mice by TSG administration using the above-mentioned DNA vaccine. The production of fimbria-specific IgA and IgG antibodies in saliva and serum IgG antibody was significantly stimulated by TSG immunization. Injection of DNA vaccine into salivary gland elicited high-level production of antigen-specific IgG antibody, similar to that induced following intramuscular immunization. The major IgG subclass that recognized fimbriae was IgG2a in serum from pcDNA3/fimA-immunized mice. Reverse transcription-PCR analysis of mononuclear cells from salivary glands showed that levels of Th2 cytokine-specific mRNA were higher in the immunized group than in the nonimmunized group. In addition, TSG DNA immunization resulted in the generation of antigen-specific CTL in spleen. These results indicate that TSG immunization with plasmid DNA may represent a genetic immunization strategy against infection by oral and pharyngeal pathogens that may invade local, mucosal surfaces.

Animals↗
PubMed1999

Iron reductase for magnetite synthesis in the magnetotactic bacterium Magnetospirillum magnetotacticum.

Ferric iron reductase was purified from magnetotactic bacterium Magnetospirillum (formerly Aquaspirillum) magnetotacticum (ATCC 31632) to an electrophoretically homogeneous state. The enzyme was loosely bound on the cytoplasmic face of the cytoplasmic membrane and was found more frequently in magnetic cells than in nonmagnetic cells. The molecular mass of the purified enzyme was calculated upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis to be about 36 kDa, almost the same as that calibrated by gel filtration analysis. The enzyme required NADH and flavin mononucleotide (FMN) as optimal electron donor and cofactor, respectively, and the activity was strongly inhibited by Zn2+ acting as a partial mixed-type inhibitor. The Km values for NADH and FMN were 4.3 and 0. 035 microM, respectively, and the Ki values for Zn2+ were 19.2 and 23.9 microM for NADH and FMN, respectively. When the bacterium was grown in the presence of ZnSO4, the magnetosome number in the cells and the ferric iron reductase activity declined in parallel with an increase in the ZnSO4 concentration of the medium, suggesting that the ferric iron reductase purified in the present study may participate in magnetite synthesis.

FMN Reductase↗
PubMed1999

Bni1p regulates microtubule-dependent nuclear migration through the actin cytoskeleton in Saccharomyces cerevisiae.

The RHO1 gene encodes a yeast homolog of the mammalian RhoA protein. Rho1p is localized to the growth sites and is required for bud formation. We have recently shown that Bni1p is one of the potential downstream target molecules of Rho1p. The BNI1 gene is implicated in cytokinesis and the establishment of cell polarity in Saccharomyces cerevisiae but is not essential for cell viability. In this study, we screened for mutations that were synthetically lethal in combination with a bni1 mutation and isolated two genes. They were the previously identified PAC1 and NIP100 genes, both of which are implicated in nuclear migration in S. cerevisiae. Pac1p is a homolog of human LIS1, which is required for brain development, whereas Nip100p is a homolog of rat p150(Glued), a component of the dynein-activated dynactin complex. Disruption of BNI1 in either the pac1 or nip100 mutant resulted in an enhanced defect in nuclear migration, leading to the formation of binucleate mother cells. The arp1 bni1 mutant showed a synthetic lethal phenotype while the cin8 bni1 mutant did not, suggesting that Bni1p functions in a kinesin pathway but not in the dynein pathway. Cells of the pac1 bni1 and nip100 bni1 mutants exhibited a random distribution of cortical actin patches. Cells of the pac1 act1-4 mutant showed temperature-sensitive growth and a nuclear migration defect. These results indicate that Bni1p regulates microtubule-dependent nuclear migration through the actin cytoskeleton. Bni1p lacking the Rho-binding region did not suppress the pac1 bni1 growth defect, suggesting a requirement for the Rho1p-Bni1p interaction in microtubule function.

Actins↗
PubMed1999

Unusual appearances of uterine leiomyomas: MR imaging findings and their histopathologic backgrounds.

Typical appearances of uterine leiomyoma at magnetic resonance (MR) imaging are well established, and diagnosis is usually easy. However, cases that, are extremely difficult to differentiate from other conditions are occasionally encountered. To understand the wide spectrum of MR imaging findings, such unusual appearances can be classified into three categories: degeneration and other histopathologic findings, specific types of unusual leiomyomas, and unusual growth patterns. The common types of degeneration are hyaline (>60% of cases), cystic (approximately 4%), myxoid, and red. Edema is not a phenomenon of degeneration but is a common histopathologic finding (approximately 50% of cases). Hemorrhage, necrosis, and calcification (approximately 4% of cases) may also be observed. Specific types of unusual leiomyomas include lipoleiomyoma and myxoid leiomyoma, which may have MR imaging features characteristic enough to allow differentiation from other gynecologic and nongynecologic diseases. Intravenous leiomyomatosis, metastasizing leiomyoma, diffuse leiomyomatosis, and peritoneal disseminated leiomyomatosis represent unusual growth patterns; other unusual growth patterns are retroperitoneal growth, parasitic growth, and the pattern that may occur in cervical leiomyoma. Because leiomyomas are the most common gynecologic tumors and are exclusively benign, it is important to be familiar with the variety of MR imaging appearances of uterine leiomyomas to distinguish them from other significant diseases.

Female↗
PubMed1999

Apoptosis and overexpression of bax protein and bax mRNA in smooth muscle cells within intimal hyperplasia of human radial arteries : analysis with arteriovenous fistulas used for hemodialysis.

There is a type of arteriosclerosis with remodeling of middle-size arteries in which intimal hyperplasia of smooth muscle cells (SMCs) plays the main role, and there are few macrophages, T lymphocytes, and foam cells. It is unknown whether apoptosis and the expression of Bax, an inducer of apoptosis, are increased according to the progression of this type of human arteriosclerosis, which is different from so-called atherosclerosis. Bax heterodimerizes with Bcl-2, an inhibitor of apoptosis, and the ratio of Bax to Bcl-2 determines cellular apoptosis or survival. Thus, we investigated apoptosis and the expressions of Bax, bax mRNA, and Bcl-2 in human arteriovenous (AV) fistulas used for hemodialysis, a representative of arteriosclerosis of the aforementioned type. The material was 20 radial arteries obtained from 20 patients with chronic renal failure undergoing AV shunt surgery. SMCs, macrophages, and T lymphocytes were immunohistochemically identified at the light microscopic (LM) level. Apoptosis was detected by in situ terminal deoxynucleotidyl transferase (TdT)-mediated digoxigenin-dUTP nick end labeling (TUNEL) at both the LM and electron microscopic (EM) level. Cell proliferating activity was estimated by proliferating cell nuclear antigen (PCNA). Bax and Bcl-2 were detected by immunohistochemistry and Western blot analysis. Expression of bax mRNA was detected by in situ hybridization. LM TUNEL-positive cells in both the intima and media were significantly increased according to the percent stenosis of the vessels. EM analysis revealed that ultrastructures of apoptotic SMCs were seen in both synthetic and contractile phenotypes. Their frequency of occurrence in the intima and media were greater in those vessels with >50% stenosis than in those with <50% stenosis (5.2+/-0.7% versus 1.0+/-0.3% in the intima and 2. 1+/-0.5% versus 0.2+/-0.1% in the media). The proportion of apoptotic SMCs with ruptured plasma membranes was greater than that of apoptotic SMCs with intact membranes in the intima of the former (4.1+/-0.6% versus 1.1+/-0.1%). Only those SMCs with apoptotic ultrastructures had TUNEL-positive nuclei with moderate or marked accumulation of immunogold particles at the EM level. However, ultrastructures of oncosis (primary necrosis) were not observed. Immunohistochemical analyses showed significant positive correlations between percent stenosis of vessels and the percentage of either PCNA-positive intimal cells or Bax-positive areas in the intima and media. Bcl-2-positive cells were not observed in the intima but mainly in the outer media. The percentage of Bcl-2-positive medial cells was definitely decreased at an early stage after formation of the AV fistula but did not change according to the duration of hemodialysis or the progression of arteriosclerosis. Western blot analysis of Bax or Bcl-2 and in situ hybridization of bax mRNA confirmed the immunohistochemical data. Thus, regulation of cellularity in intimal hyperplasia of SMCs in human arteriosclerosis with remodeling is mediated by proliferation and apoptosis but not oncosis. The apoptosis is probably induced by an increase in the Bax to Bcl-2 ratio.

Adult↗
PubMed1999

Inhibition of microtubule assembly by HPC-1/syntaxin 1A, an exocytosis relating protein.

HPC-1/syntaxin 1A (HPC-1), which has been identified as a presynaptic membrane protein, is believed to regulate the synaptic exocytosis as a component of t-SNARE. The distribution of the protein, however, is not restricted to the synaptic terminal, but it has been found to locate on the axonal membrane. When the expression of HPC-1 was suppressed, neurite sprouting was enhanced in cultured neurons. These findings suggest that HPC-1 possesses other functions than the regulation of the membrane fusion in neurotransmitter release. Rather it may also participate in the morphogenesis of neurons through membrane fusion, and possibly through cytoskeleton. HPC-1 has a sequence resemble to the assembly promoting sequence of heat stable MAPs in residues 89-106, suggesting that it can bind tubulin and be involved in microtubule system. Thus, both the tubulin binding property and the effect on microtubule assembly of HPC-1 were examined in vitro using a mutated HPC-1 lacking the C-terminal transmembrane region (HPC-deltaTM), which was overexpressed in E. coli. Affinity column chromatography showed that tubulin was found to bind HPC-1 directly. Synthetic peptide which corresponds to the residues 89-106 competitively inhibited the tubulin-HPC-1 binding, indicating that the sequence is responsible for the tubulin binding. In addition, chemical cross-linking with EDC revealed that one HPC-1 molecule can bind per one monomeric tubulin molecule. Light scattering measurement of microtubule polymerization showed that HPC-1 decreased the rate of the pure tubulin polymerization. Direct observation of single microtubules under dark-field microscopy showed that the growth rate of microtubule decreased by HPC-1. After shortening stopped, microtubules often spent attenuate phases, in which neither growing nor shortening was detected. When another mutant HPC-1 which is composed of residues 1-97 and lacks tubulin binding activity was used, however, the suppression of microtubule polymerization was not observed. These results suggest that HPC-1 is a potent regulator of microtubule polymerization, which directly bind tubulin subunit and decrease the polymerization activity.

Amino Acid Sequence↗
PubMed1999

Effectiveness of 1,25-dihydroxyvitamin D supplementation on blood pressure reduction in a pseudohypoparathyroidism patient with high renin activity.

A 42-year-old man had biochemical and somatic abnormalities compatible with pseudohypoparathyroidism type I (PsHP) and also had high plasma renin activity (PRA). After 1,25-dihydroxyvitamin D (calcitriol) supplementation the systolic/diastolic blood pressure, assessed by 24-hour non-invasive ambulatory blood pressure monitoring, was reduced from 145/96 mm Hg to 128/85 mm Hg with normalization of the serum calcium level and its related hormones, as well as decreased PRA. Calcitriol supplementation successfully reduced the blood pressure in this patient with PsHP and a high PRA, suggesting that calcium-related hormones and/or the renin-angiotensin system were involved in lowering the blood pressure.

Adult↗
PubMed1999

Temperature change in human muscle during and after pulsed short-wave diathermy.

STUDY DESIGN: A time series design was used, with the dependent variable being gastrocnemius muscle temperature at a depth of 3 cm. OBJECTIVES: To determine the rate of temperature rise and the rate of post-treatment temperature decline in skeletal muscle following the application of pulsed short-wave diathermy (PSWD). BACKGROUND: Data on PSWD rate and longevity of heating are 20 years old and outdated. With the recent introduction of advanced diathermy equipment, results of our study would provide clinicians with much needed information regarding treatment duration. METHODS AND MEASURES: A 23-gauge thermistor was inserted into the center of the medial head of the anesthetized gastrocnemius muscle, 3 cm below the skin's surface of 20 subjects. The PSWD (27.12 MHz frequency) was applied using the following parameters: 800 bursts per second; 400 microseconds burst duration; 850 microseconds interburst interval; with a peak root mean square (RMS) amplitude of 150 W per burst and an average RMS output of 48 W. Temperature changes were documented every 5 minutes during the treatment and additionally at 5 and 10 minutes following treatment. RESULTS: The average baseline and peak temperatures were 35.84 +/- 0.93 degrees C and 39.80 +/- 0.83 degrees C, respectively. Mean temperature increases were: 1.36 +/- 0.90 degrees C (5 min); 2.87 +/- 1.44 degrees C (10 min); 3.78 +/- 1.19 degrees C (15 min); 3.49 +/- 1.13 degrees C (20 min). After the treatment terminated, intramuscular temperature dropped 0.97 +/- 0.68 degree C in 5 minutes and 1.78 +/- 0.69 degrees C in 10 minutes. CONCLUSIONS: PSWD is an effective modality if temperature elevation of deep tissue over a large area is the clinical objective.

Adult↗
PubMed1999

Molecular cloning of the gene for the key carbocycle-forming enzyme in the biosynthesis of 2-deoxystreptamine-containing aminocyclitol antibiotics and its comparison with dehydroquinate synthase.

The 2-deoxystreptamine aglycon is a common structural feature found in aminocyclitol antibiotics including neomycin, kanamycin, tobramycin, gentamicin, sisomicin, butirosin and ribostamycin. A key enzyme involved in the biosynthesis of the 2-deoxystreptamine moiety is 2-deoxy-scyllo-inosose (DOI) synthase which catalyses the carbocycle formation from D-glucose-6-phosphate to 2-deoxy-scyllo-inosose. The recent success of isolating the 2-deoxy-scyllo-inosose synthase from Bacillus circulans prompted us to clone the gene responsible for this important enzyme by the use of reverse genetics approach. With the aid of DNA probes constructed on the basis of the amino-terminal sequence of the purified 42 kDa subunit of the enzyme, the responsible gene btrC was successfully cloned. Subsequently the btrC gene was heterologously expressed in Escherichia coli, and the 2-deoxy-scyllo-inosose synthase activity of the recombinant polypeptide was confirmed by chemical analysis. The btrC gene encodes a protein composed of 368 amino acids with a molecular mass of 40.7 kDa. Our previous proposal for the similarity of 2-deoxy-scyllo-inosose synthase to dehydroquinate synthase has been confirmed on the basis of their amino acid sequences. Significant differences in the sequences can also be observed however, particularly in the crucial substrate recognition regions. Comparison of the BtrC sequence with those of biosynthetic enzymes for other related microbial products is also discussed.

Amino Acid Sequence↗
PubMed1999

[Warfarin potassium for impending central retinal vein occlusion].

PURPOSE: We reviewed the records of 10 patients who had impending central retinal vein occlusion in order judge whether anticoagulant treatment with warfarin potassium (Warfarin) was indicated. PATIENTS: 6 men and 4 women, ranging in age from 25 to 83 (average 55) years were studied. RESULTS: Of 6 eyes, retinal hemorrhage disappeared completely within 6 months. Four patients whose visual acuity was 0.1 or less at one month needed photocoagulation. Four other patients whose late venous circulation time at fluorescein angiography improved within 30 seconds had good visual prognosis, 3 eyes of 4 patients aged 65 or older were not successful in regaining their visual acuity. CONCLUSION: Warfarin was not effective for patients who had clearly lost their visual acuity and the elderly in this series. Late venous circulation time at fluorescein angiography was a useful index for this treatment.

Adult↗
PubMed1999

Recombinant adenovirus expressing wild-type p53 is antiangiogenic: a proposed mechanism for bystander effect.

Angiogenesis is required for the growth and progression of malignancies. Recent studies have demonstrated that genetic alterations may accompany acquisition of the angiogenic phenotype. The tumor suppressor gene p53 is most frequently mutated in human cancers and is also known to be a transcriptional regulator of a variety of genes. Here, we investigated the antiangiogenic effect of the wild-type p53 (wt-p53) gene transfer on a human non-small cell lung cancer cell line. Mutant p53-expressing H226Br non-small cell lung cancer cells were transduced with the wt-p53 gene using a recombinant adenoviral vector (Ad5CMVp53) and applied to semiquantitative reverse transcription-PCRs for the detection of altered mRNA expression of angiogenic and/or antiangiogenic factors. In vivo neovascularization assay of Ad5CMVp53-infected cells was then performed using a membrane-diffusion chamber system s.c. transplanted in nu/nu mice. We also evaluated the effect of Ad5CMVp53-infected H226Br cells on nontransduced tumor cells in vivo by s.c. inoculating mixture of cells into nu/nu mice. Ad5CMVp53 infection markedly inhibited the expression of an angiogenic factor, vascular endothelial growth factor, and increased the expression of a novel antiangiogenic factor, brain-specific angiogenesis inhibitor 1, resulting in reduced neovascularization in vivo. Mixing experiments showed that tumor cells transduced with the wt-p53 gene inhibited the in vivo tumor growth of adjacent nontransduced cells. Our data suggest that a recombinant adenovirus expressing the wt-p53 gene is antiangiogenic, which may explain, in part, the mechanism of the bystander effect induced by the wt-p53 gene transfer on adjacent tumor cells.

Adenoviruses, Human↗
PubMed1999

[Regulation of gene expression in cultured rabbit corneal stromal cells with recombinant adenovirus using the Cre/loxP system].

PURPOSE: To control exogenous gene expression is an important norm in human gene therapy. We attempted to control lac Z gene expression in a rabbit corneal stromal cell (RCS) culture system with recombinant adenovirus (Ad) and the Cre/loxP system. MATERIALS & METHODS: The RCS was transfected with an Ad which expressed the lac Z gene by excisional deletion of stuffer DNA, Ax CA LNLZ. Four days after the transfection, the cells were also transfected with a Cre-producing Ad, Ax CA NCre. RESULT: Few cells (0.8%) of the RCS transfected with Ax CA LNLZ expressed the lac Z gene. After the transfection of Ax CA NCre, all cells strongly expressed the lac Z gene. This result showed that recombinant adenovirus using the Cre/loxP system was capable of controlling exogenous gene expression in cultured rabbit corneal stromal cells. CONCLUSION: We suggest that recombinant adenovirus using the Cre/loxP system is useful for studying ophthalmic gene therapy.

Adenoviridae↗
PubMed1999

Effects of total parenteral nutrition on rat bile canaliculi: a stereologic analysis.

OBJECTIVE: To quantitate, in a stereologic manner, changes in bile canalicular morphology before and after choleretic infusion of total parenteral nutrition (TPN) and to determine whether TPN produces changes in localized regions within the hepatic lobule. STUDY DESIGN: Livers were obtained from sham-operated on normal adult male rats (control) and from rats that received intravenous TPN solution containing 20% glucose and 3.5% Molipron F. The tissues, obtained by a rigorous sampling procedure, were systematically subjected to stereologic analysis. Measurements were made on electron micrographs at two levels of magnification by point, intersection and profile counts, and then volume, surface area and length were estimated per unit parenchymal volume. RESULTS: The surface area of the canalicular wall per parenchymal volume increased significantly (from 5.33 x 10(-2) to 6.73 x 10(-2) microns 2/micron 3) after TPN treatment, as did the length of microvilli (from 0.241 to 0.267 microns/micron 3). However, the volume of bile canalicular lumina per parenchymal volume (0.306% and 0.320%), total length of bile canaliculi (1.05 x 10(-2) and 1.06 x 10(-2) microns/micron 3) and diameter of microvilli (8.73 x 10(-2) and 8.94 x 10(-2) microns) remained constant. CONCLUSION: These results indicate that changes in canalicular shape and microvillus hypertrophy may cause lowering efficiency of the bile flow rate.

Animals↗
PubMed1999

[A phase I trial of adenoviral p53 gene therapy for non-small cell lung cancer].

Lung cancer is one of the leading causes of cancer deaths worldwide. The high mortality rate for lung cancer results from the absence of standard therapeutic strategies, suggesting that lung cancer may be a suitable target disease for a novel gene-based therapy. Restoration of the function of a single pivotal gene product appears sufficient to mediate antitumor effects that are potentially clinically significant. Preclinical studies in animal models have demonstrated tumor regression following intratumoral administration of an adenovirus vector containing The wild-type tumor suppressor p53 gene. The efficacy and safety of the p53 gene therapy protocol for non-small cell lung cancer are now being evaluated in clinical trials. Although much research needs to be done following trials in the earliest stages, the treatment may offer a unique mechanism of action with a potentially high therapeutic index. This article reviews recent highlights in this rapidly evolving field.

Adenoviridae↗