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Biomedical subjects

T Fujii

Publications and source records attributed to T Fujii.

At least 37 records · Page 2Linked to original sources

Human mesenchymal stem cells successfully improve skin-substitute wound healing.

BACKGROUND: Large or deteriorated skin defects are sometimes life threatening. There is increasing evidence that adult stem cells are useful for tissue regeneration. Human mesenchymal stem cells (hMSCs) are self-renewing and are potent in differentiating into multiple cells and tissues. OBJECTIVES: To investigate the effects of hMSCs in cutaneous wound healing. METHODS: Wound healing was studied in an hMSC-populated porcine skin substitute, using a nude rat model to minimize immune reactions. Full-thickness skin and soft tissue defects of 1.5 x 1.5 cm in size, including the panniculus carnosus, were excised and covered with hMSCs and basic fibroblast growth factor (bFGF)-soaked skin substitutes and an evaluation was made of wound size, histology and protein expression at 3, 7 and 42 days after injury. RESULTS: The wound size was significantly smaller in the hMSC-treated groups (P < 0.01) and any dose of bFGF (1, 10, 100 microg) enhanced the healing (P < 0.01). The re-epithelialization markers integrin alpha3 and skin-derived antileucoproteinase were remarkably increased with the presence of bFGF in a dose-dependent manner, while the mesenchymal cell surface markers CD29 and CD44 were downregulated in a time-dependent manner. Human pancytokeratin, which does not cross-react with rat antigens, was observed by Western blotting at 38 kDa and 42 kDa from the hMSC-treated tissues on day 7. The expression levels were elevated by 10 microg bFGF (P < 0.01). The immunohistochemical expression of human pancytokeratin was only observed in the hMSC-treated groups. CONCLUSIONS: These data suggest that hMSCs together with bFGF in a skin defect model accelerate cutaneous wound healing as the hMSCs transdifferentiate into the epithelium.

Animals↗

Immunological development of preterm infants in early infancy.

To evaluate the immunological development of preterm infants, especially in early infancy, we examined the serum cytokine levels and the expression of Th2 and Th1 chemokine receptors, CCR4 and CCR5, on days 0, 14 and 28 in 16 low birth weight infants (1720.38 +/- 502.80 g) born at less than 37 (33.63 +/- 3.29) weeks of gestation. Using an enzyme-linked immunosorbent assay (ELISA), serum interleukin (IL)-4 levels exhibited an increase on day 14, but decreased to the initial level on day 28 (P < 0.05). The significant elevation of serum transforming growth factor (TGF)-beta levels was confirmed on day 14 (P < 0.05) but decreased to the initial level on day 28 (P < 0.05). The expression of CCR4 and CCR5 were examined using reverse transcription-polymerase chain reaction (RT-PCR) and flow cytometric analysis. The RT-PCR confirmed the expression of CCR5-mRNA soon after birth, while there was no expression of CCR4-mRNA. Thereafter, the expression of CCR4-mRNA increased significantly and reached the level of CCR5-mRNA expression on day 28 (P < 0.05). Flow cytometric analysis, however, revealed that the expression levels of both CCR4 and CCR5 were low at birth. Thus, CCR4(+) CD4(+) cells were significantly increased from days 0-28 (P < 0.05), while CCR5(+) CD4(+) cells were not. Increased IL-4 and TGF-beta synthesis as well as increased CCR4(+) CD4(+) cells suggest that, under extra-maternal circumstances, there is a shift in bias toward Th2 responses even in preterm infants soon after delivery, while they may be capable of developing Th1 mediated responses soon after birth.

Actins↗

Partial deletions of the W chromosome due to reciprocal translocation in the silkworm Bombyx mori.

In the silkworm, Bombyx mori (female, ZW; male, ZZ), femaleness is determined by the presence of a single W chromosome, irrespective of the number of autosomes or Z chromosomes. The W chromosome is devoid of functional genes, except the putative female-determining gene (Fem). However, there are strains in which chromosomal fragments containing autosomal markers have been translocated on to W. In this study, we analysed the W chromosomal regions of the Zebra-W strain (T(W;3)Ze chromosome) and the Black-egg-W strain (T(W;10)+(w-2) chromosome) at the molecular level. Initially, we undertook a project to identify W-specific RAPD markers, in addition to the three already established W-specific RAPD markers (W-Kabuki, W-Samurai and W-Kamikaze). Following the screening of 3648 arbitrary 10-mer primers, we obtained nine W-specific RAPD marker sequences (W-Bonsai, W-Mikan, W-Musashi, W-Rikishi, W-Sakura, W-Sasuke, W-Yukemuri-L, W-Yukemuri-S and BMC1-Kabuki), almost all of which contained the border regions of retrotransposons, namely portions of nested retrotransposons. We confirmed the presence of eleven out of twelve W-specific RAPD markers in the normal W chromosomes of twenty-five silkworm strains maintained in Japan. These results indicate that the W chromosomes of the strains in Japan are almost identical in type. The Zebra-W strain (T(W;3)Ze chromosome) lacked the W-Samurai and W-Mikan RAPD markers and the Black-egg-W strain (T(W;10)+(w-2) chromosome) lacked the W-Mikan RAPD marker. These results strongly indicate that the regions containing the W-Samurai and W-Mikan RAPD markers or the W-Mikan RAPD marker were deleted in the T(W;3)Ze and T(W;10)+(w-2) chromosomes, respectively, due to reciprocal translocation between the W chromosome and the autosome. This deletion apparently does not affect the expression of Fem; therefore, this deleted region of the W chromosome does not contain the putative Fem gene.

Animals↗

Random amplified polymorphic DNA-PCR based cloning of markers to identify the beer-spoilage strains of Lactobacillus brevis, Pediococcus damnosus, Lactobacillus collinoides and Lactobacillus coryniformis.

AIMS: Beer-spoilage ability of lactic acid bacteria such as Lactobacillus brevis is a strain-dependent phenomenon in which the mechanism has not yet been completely clarified. In order to systematically identify genes that contribute to beer-spoilage, large-scale random amplified polymorphic DNA (RAPD)-based cloning methods was carried out. METHODS AND RESULTS: A systematic RAPD polymerase chain reaction (PCR) analysis using 600 primers was performed on beer-spoilage and on nonspoilage strains of L. brevis. Among 600 primers, three were found to amplify a single locus highly specific to beer-spoilage strains. DNA sequencing of this locus revealed a three-part operon encoding a putative glycosyl transferase, membrane protein and teichoic acid glycosylation protein. PCR analysis of typical beer-spoilage lactic acid bacteria suggested that this locus is highly specific to beer-spoilage strains. CONCLUSION: The cloned markers are highly specific to identify the beer-spoilage strains not only in L. brevis but also in Pediococcus damnosus, Lactobacillus collinoides and Lactobacillus coryniformis. SIGNIFICANCE AND IMPACT OF THE STUDY: This paper proves that RAPD-PCR is an efficient method for cloning the strain-specific genes from bacteria. The markers described here is one of the most useful tools to identify the beer-spoilage strains of lactic acid bacteria.

Beer↗

Elution and adsorptive concentration of Japanese cedar (Cryptomeria japonica) pollen allergen in environmental water.

Elution of Japanese cedar pollen allergens (Cry j I and others) from pollen grains and its adsorptive concentration onto hydrophobic and hydrophilic surfaces were investigated using the surface plasmon resonance technique. Results showed that the allergen elution was obviously enhanced when the ion concentration was higher than that within the human body, indicating that the pollen tend to release its allergen in environmental water having a high ion concentration. However, higher adsorption capacity was observed on hydrophobic surface than hydrophilic surface. These results indicate that water puddles on roadsides beside heavy traffic including large amounts of ion compounds and hydrophobic diesel exhaust particles (DEPs) are a pollen allergen-DEP complex generator. DEPs are easily absorbed into the living body; therefore these mechanisms may be responsible for causing the highest incidence of pollinosis among residents living alongside roads with heavy automobile traffic.

Adsorption↗

Silica deposition in relation to ageing of leaf tissues in Sasa veitchii (Carriere) Rehder (Poaceae: Bambusoideae).

BACKGROUND AND AIMS: Silica deposition is one of the important characteristics of plants in the family Poaceae. There have been many investigations into the distribution, deposition and physiological functions of silica in this family. Two hypotheses on silica deposition have been proposed based on these studies. First, that silica deposition occurs passively as a result of water uptake by plants, and second, that silica deposition is controlled positively by plants. To test these two apparently contradictory hypotheses, silica deposition in relation to the ageing of leaf tissues in Sasa veitchii was investigated. METHODS: Tissues were examined using a light microscope and a scanning electron microscope equipped with an energy dispersive X-ray microanalyser. KEY RESULTS: The deposition process differed depending on cell type. In mesophyll tissue, fusoid cells deposited large amounts of silica depending on leaf age after maturation, while chlorenchyma cells deposited little. In epidermal tissue, comprised of eight cell types, only silica cells deposited large amounts of silica during the leaf's developmental process and none after maturation. Bulliform cells, micro-hairs and prickle hairs deposited silica densely and continuously after leaf maturation. Cork cells, guard cells, long cells and subsidiary cells deposited silica at low levels. CONCLUSIONS: The significance of these observations is discussed in relation to the two hypotheses proposed for silica deposition in Poaceae. The results of the present study clearly indicate that both hypotheses are compatible with each other dependent on cell types.

Microscopy, Electron, Scanning↗

Image processing methods to obtain symmetrical distribution from projection image.

Flow visualization and measurement of cross-sectional liquid distribution is very effective to clarify the effects of obstacles in a conduit on heat transfer and flow characteristics of gas-liquid two-phase flow. In this study, two methods to obtain cross-sectional distribution of void fraction are applied to vertical upward air-water two-phase flow. These methods need projection image only from one direction. Radial distributions of void fraction in a circular tube and a circular-tube annuli with a spacer were calculated by Abel transform based on the assumption of axial symmetry. On the other hand, cross-sectional distributions of void fraction in a circular tube with a wire coil whose conduit configuration rotates about the tube central axis periodically were measured by CT method based on the assumption that the relative distributions of liquid phase against the wire were kept along the flow direction.

Journal Article↗

Visualization and void fraction measurement of gas-liquid two-phase flow in plate heat exchanger.

Adiabatic and boiling gas-liquid two-phase flows in a simulated plate heat exchanger with a single-ribbed channel were visualized by a thermal neutron radiography method. In the experiments under adiabatic condition, the air-water two-phase flows in an aluminum test section were visualized. In the boiling two-phase flow experiments, chlorofluorocarbon R141b was used as the working fluid. Two-dimensional distributions of void fraction were measured from visualized images via some image processing techniques. As a result, it was shown that both the phases tended to flow straight in the ribbed channel, and mixing of gas and liquid phases was weak. Moreover, when working fluids flew into the test section as a gas-liquid mixture, the phase distributions were strongly affected by a liquid pool at the test section inlet.

Journal Article↗

Fabrication of microstructures in photosensitive biodegradable polymers for tissue engineering applications.

Combining the MEMS technology and biology requirements for tissue engineering, the fabrication processes of microstructured chambers and microchannels made in biodegradable photosensitive polymers are presented. The fabrication processes, based on softlithography are very fast and flexible. Various single and multistepwise microstructures could be achieved using the biodegradable polymers. Microstructures down to 50microm, which are suitable for liver reconstructs, could be fabricated. As the pCLLA acrylate photosensitive polymer has interesting property for implantable bioreactors, that is, its softness, we examined the ability of various mammalian cells to grow and spread on it. With Hep G2 cells, human umbilical blood vessel endothelial cells (HUVEC), 3T3-L1 mouse fibroblasts, static cultures could be successfully performed on single stepwise microstructures. Then, by using this photosensitive biodegradable polymer, a microstructure with simple fluidic channels is fabricated and a perfusion experiment could be carried out. Both cell cultures and perfusion experiments suggested the possibility to use the present photosensitive polymer as microfluidic supports for biodegradable bioreactors for implantation applications.

3T3-L1 Cells↗

Chromoendoscopy using indigo carmine dye spraying with magnifying observation is the most reliable method for differential diagnosis between non-neoplastic and neoplastic colorectal lesions: a prospective study.

BACKGROUND AND AIMS: Differential diagnosis between non-neoplastic and neoplastic lesions is very important at colonoscopy, since removal or biopsy of non-neoplastic polyps wastes time and resources. We therefore conducted a prospective study to examine whether indigo carmine dye spraying with and without magnification is more reliable than the conventional method for differential diagnosis. PATIENTS AND METHODS: 122 patients with 206 lesions of 10 mm or smaller were recruited into this study. All lesions detected on colonoscopy were first diagnosed using the conventional view, then at chromoendoscopy using 0.2 % indigo carmine, and finally at chromoendoscopy with magnification. The diagnosis at each step were recorded consecutively. All lesions were finally categorized as neoplastic or non-neoplastic according to pit pattern; non-neoplastic lesions were biopsied for histological evaluation, and all the neoplastic ones were removed endoscopically. The accuracy rate of each type of endoscopic diagnosis was evaluated, using histological findings as reference. RESULTS: Histologically, 46 lesions (22 %) were non-neoplastic and 160 (78 %) were neoplastic. The overall diagnostic accuracies by conventional view, chromoendoscopy, and chromoendoscopy with magnification were 84.0 % (173/206), 89.3 % (184/206) and 95.6 % (197/206), respectively. CONCLUSION: Chromoendoscopy with magnification is the most reliable method for determining whether a colorectal lesion is non-neoplastic or neoplastic.

Adult↗

Post-traumatic leptomeningeal cyst mimicking a skull tumour in an adult.

A 53-year-old female presented with a post-traumatic leptomeningeal cyst manifesting as bulging of the scalp, dizziness and tinnitus. She had known of the bulging of her forehead for about 20 years. She had suffered an injury to the head in childhood. Brain CT revealed a bone cyst associated with a round bone defect in the left frontal bone, bulging of the very thin outer layer and the defective inner layer. She was treated surgically with a diagnosis of skull tumour, but only gray cystic membranous tissue was found. The dural defect was repaired with fascia and the bone defect with bone cement. Bulging of the skull in adults can be caused by a bone cyst originating from a skull fracture.

Arachnoid Cysts↗

Marinospirillum insulare sp. nov., a novel halophilic helical bacterium isolated from kusaya gravy.

A novel species that belongs to the genus Marinospirillum is described on the basis of phenotypic characteristics, phylogenetic analysis of 16S rRNA and gyrB gene sequences and DNA-DNA hybridization. Four strains of helical, halophilic, Gram-negative, heterotrophic bacteria were isolated from kusaya gravy, which is fermented brine that is used for the production of traditional dried fish in the Izu Islands of Japan. All of the new isolates were motile by means of bipolar tuft flagella, of small cell size, coccoid-body-forming and aerophilic; it was concluded that they belong to the same bacterial species, based on DNA-DNA hybridization values (>70% DNA relatedness). DNA G+C contents of the new strains were 42-43 mol% and they had isoprenoid quinone Q-8 as the major component. Phylogenetic analysis of 16S rRNA gene sequences indicated that the new isolates were members of the genus Marinospirillum; sequence similarity of the new isolates to Marinospirillum minutulum, Marinospirillum megaterium and Marinospirillum alkaliphilum was 98.5, 98.2 and 95.2%, respectively. Phylogenetic analysis based on the gyrB gene indicated that the new isolates had enough phylogenetic distance from M. minutulum and M. megaterium to be regarded as different species, with 84.7 and 78.7% sequence similarity, respectively. DNA-DNA hybridization showed that the new isolates had <36% DNA relatedness to M. minutulum and M. megaterium, supporting the phylogenetic conclusion. Thus, a novel species is proposed: Marinospirillum insulare sp. nov. (type strain, KT=LMG 21802T=NBRC 100033T).

Animals↗

Pirfenidone attenuates expression of HSP47 in murine bleomycin-induced pulmonary fibrosis.

Heat shock protein (HSP) 47, a collagen-specific molecular chaperone, is involved in the processing and/or secretion of procollagen. The present study was undertaken to investigate whether treatment with the antifibrotic drug pirfenidone attenuates the bleomycin (BL)-induced overexpression of HSP47 in the lungs. Male ICR mice were intravenously injected with BL or saline (SA). Pirfenidone or control drug (CD) was administered 14 days after commencement of BL or SA, and continued throughout the course of the experiment. The mice were randomly divided into three experimental groups: 1) SA-treated with CD (SA group); 2) BL-treated with CD (BL group); and 3) BL-treated with pirfenidone (pirfenidone group). Lungs of the pirfenidone group showed a marked reduction of fibrotic lesions compared with the corresponding BL group. Immunohistochemical studies showed that BL treatment significantly increased the number of macrophages, myofibroblasts, HSP47-positive type II pneumocytes and HSP47-positive interstitial spindle-shaped cells. Treatment with pirfenidone significantly reduced the number of these cells compared with the corresponding BL group. Furthermore, treatment with pirfenidone significantly suppressed the BL-induced increase of the positive ratio of HSP47 and alpha-smooth muscle actin to interstitial spindle-shaped cells. The present study results showed that pirfenidone inhibited heat shock protein 47-positive cells and myofibroblasts, the principal cells responsible for the accumulation and deposition of extracellular matrix seen in pulmonary fibrosis.

Analysis of Variance↗

Pathological change of articular cartilage in the mandibular head treated with immunosuppressant FK 506.

While several reports have documented immunosuppressant-induced osteoporosis, the exact mechanism of the pathological change of the joint remains to be clarified. In the present study, we have demonstrated the pathological change of the articular cartilage in the mandibular head of five Sprague-Dawley rats administered with the immunosuppressant FK 506 for 28 days. Three-dimensional micro-computed tomography of the mandibular heads in treated rats showed a significant decrease in trabecular bone volume compared to control rats. Histological observation revealed atrophic change of the articular cartilage. Immunohistological observation using anti-proliferative cell nuclear antibody (PCNA), type I, II, and type X collagen antibodies showed significantly decreased proliferation and differentiation of chondrocytes in the articular cartilage compared with the control group (p<0.05). Tartrate-resistant acid phosphatase (TRAP) staining revealed no significant difference in the numbers of osteoclasts at the chondro-osseous junction. Thus, FK 506 administration inhibited chondrogenic cell proliferation and differentiation and might cause osteoporotic change of subcartilage trabecular bone that subsequently forms in the mandibular head.

Animals↗

[Unstable angina pectoris associated with systemic lupus erythematosus and arterio-sclerotic obstruction in whom hemophagocytic syndrome appeared after emergent operation; report of a case].

A 45-year-patient who suffered from old myocardial infarction (OMI) associated with systemic lupus erythematosus (SLE) and arterio-sclerotic obstruction (ASO) had unstable angina. Emergent coronary artery bypass grafting (CABG) was performed using saphenous vein graft because the left inter mammary artery was possible to be the collateral source for ASO. A high grade fever occurred without return of SLE 9 days after the operation. Pancytopenia simultaneously occurred. Hemophagocytic syndrome was diagnosed by the bone marrow examination. Pulse therapy with steroids was given and it was remarkably effected. Hemophagocytic syndrome has high mortality. However, it is difficult to distinguish from the other disease with high fever and bone marrow suppression in early period. Therefore, bone marrow examination was required to diagnose and to start the appropriate therapy as soon as possible.

Angina, Unstable↗

Observation of band renormalization effects in hole-doped high-Tc Superconductors.

We report a systematic high-resolution angle-resolved photoemission spectroscopy on high-T(c) superconductors Bi(2)Sr(2)Ca(n-1)Cu(n)O(2n+4) (n=1-3) to study the origin of many-body interactions responsible for superconductivity. For n=2 and 3, a sudden change in the energy dispersion, so called "kink", becomes pronounced on approaching (pi,0) in the superconducting state, while a kink appears only around the nodal direction in the normal state. For n=1, the kink shows no significant temperature dependence even across T(c). This could suggest that the coupling of electrons with Q=(pi,pi) magnetic mode is dominant in the superconducting state for multilayered cuprates, while the interactions at the normal state and that of single-layered cuprates have a different origin.

Journal Article↗

Papanicolaou tests and molecular analyses using new fluid-based specimen collection technology in 3000 Japanese women.

A fluid-based Papanicolaou test has been established to improve sample collection and preparation. This study was the first large-scale investigation in Japan to examine the feasibility of using fluid-based Papanicolaou specimens to detect human papillomavirus (HPV) using Hybrid Capture II and polymerase chain reaction (PCR). Three thousand patients who visited Keio University Hospital between October 2000 and February 2001 were enrolled in the study. The results of the fluid-based Papanicolaou tests corresponded well with those of conventional Papanicolaou smears (96.8% concordance). The sensitivities of cervical neoplasia detection using the fluid-based Papanicolaou test (73.9%) and Hybrid Capture II (76.3%, P=0.55) were not significantly different. Among the cervical intraepithelial neoplasia 3 and squamous cell carcinoma specimens, HPV 16 and HPV 52 were predominantly detected using the PCR method. Although some DNA samples extracted from the fluid-based specimens were degradaded, PCR and direct sequencing could be performed without difficulty even after 1 year of specimen storage. We conclude that fluid-based Papanicolaou specimens can be applied to investigate HPV infection.

DNA, Viral↗