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Biomedical subjects

T Matsuda

Publications and source records attributed to T Matsuda.

At least 55 records · Page 3Linked to original sources

EUROCARE-3: survival of cancer patients diagnosed 1990-94--results and commentary.

EUROCARE-3 analysed the survival of 1815584 adult cancer patients diagnosed from 1990 to 1994 in 22 European countries. The results are reported in tables, one per cancer site, coded according to the International Classification of Diseases (ICD)-9 classification. The main findings of the tables are summarised and commented on in this article. For most solid cancers, wide differences in survival between different European populations were found, as also reported by EUROCARE-1 and EUROCARE-2, despite a remarkable (10%) overall increase in cancer survival from 1985 to 1994. Survival was highest in northern Europe (Sweden, Norway, Finland and Iceland), and fairly good in central-southern Europe (France, Switzerland, Austria and Spain). Survival was particularly low in eastern Europe, low in Denmark and the UK, and fairly low in Portugal and Malta. The mix of tumour stage at diagnosis explains much of the survival differences for cancers of the digestive tract, female reproductive system, breast, thyroid, and also skin melanoma. For tumours of the urinary tract and prostate, the differences were explained mainly by differences in diagnostic criteria and procedures. The case mix by anatomic subsite largely explains differences in survival for head and neck cancers. For oesophagus, pancreas, liver and brain cancer, with poor prognoses, survival differences were limited. Tumours, for which highly effective treatments are available, such as testicular cancer, Hodgkin's lymphoma and some haematological malignancies, had fairly uniform survival across Europe. Survival for all tumours combined (an indicator of the overall cancer care performance of a nation's health system) was better in young than old patients, and better in women than men. The affluence of countries influenced overall cancer survival through the availability of adequate diagnostic and treatment procedures, and screening programmes.

Brain Neoplasms↗

Photoconstructs of nerve guidance prosthesis using photoreactive gelatin as a scaffold.

We devised a novel nerve prosthesis composed of an elastomeric gelatinous tube and multifilament gelatinous fibers, both of which were prepared from styrene-derivatized gelatin, which allows in situ formation of a bioactive substance-incorporated gel. An in vitro study showed that the axonal regeneration potential of a photocured gelatin layer impregnated with laminin, fibronectin, and NGF was almost comparable with that of coated Matrigel. A nerve conduit and fibers prepared from photoreactive gelatin was subjected to visible-light irradiation with rotation in the presence of camphorquinone as a photoinitiator using a custom-designed apparatus. A sample of transparent gelatinous conduit with an inner diameter of 1.2 mm and a wall thickness of 0.6 mm and gelatin fibers ranging from 10 to 100 pm in diameter were produced. The photocured elastomeric gelatinous tube was flexible and had structural integrity that allowed mechanical handling without breaking. A novel nerve guidance prosthesis composed of tubes packed with fibers was assembled. This photofabrication technology may enable the design of a tailor-made shape and rapid morphogenesis and functional recovery of damaged nerve tissue.

Animals↗

Laser-perforated membranous biomaterials induced pore size-dependent bone induction when used as a new BMP carrier.

Previously we found that laser perforation of a collagen membrane (35 microm thickness, Koken Co., Tokyo) produced an effective bone morphogenetic protein (BMP) carrier, if the created pore sizes were larger than 0.5 mm. In this study we applied the same technique to create pores of 0.2 and 1.0 mm in a thicker (1.2 mm thickness) porous biodegradable membrane made of polylactic acid and an epsilon-caprolactone copolymer (PLA-CL) to obtain an effective membranous BMP carrier with higher mechanical strength. Pieces of PLA-CL (0.5 x 1.0 x 0.12 cm) combined with rhBMP-2 (5 microg) were implanted subcutaneously into rats and processed for analyses at 1-3 weeks. The laser-perforated PLA-CL membranes equipped with 1.0 mm pores induced mineralization beginning from the margins of the pores judging from the X-ray patterns, but bone formation seemed to proceed irregularly inside the pores. In the perforated PLA-CL membrane with 1.0-mm pores bone formation did not significantly increase compared with the nonperforated one. This was due to the fact that the PLA-CL membrane was already a porous structure (85% porosity). In contrast with laser-perforated PLA-CL 0.2 mm pores, bone was induced on the collagen fibers and fiber bundles inside the pores. The different patterns of bone formation between the PLA-CL membranes with 1.0 and 0.2 mm pores seemed to be related to the active formation of perpendicular collagen fibers through the 0.2 mm pores.

Animals↗

Haptic reproduction and interactive visualization of a beating heart for cardiovascular surgery simulation.

This paper aims to achieve haptic reproduction and real-time visualization of a beating heart for cardiac surgery simulation. Unlike most forgoing approaches, the authors focus on time series datasets and propose a new framework for interactive simulation of active tissues. The framework handles both detection and response of collisions between a manipulator and a beating virtual heart. Physics-based force feedback of autonomous cardiac motion is also produced based on a stress-pressure model, which is adapted to elastic objects filled with fluid. Time series datasets of an adult man were applied to an integrated simulation system with a force feedback device. The system displays multi-dimensional representation of a beating heart and provides a basic training environment for surgical palpation. Finally, results of measurement and medical assessment confirm the achieved quality and performance of the presented framework.

Algorithms↗

Biomaterial surface chemistry dictates adherent monocyte/macrophage cytokine expression in vitro.

An in vitro human monocyte culture system was used to determine whether adherent monocyte/macrophage cytokine production was influenced by material surface chemistry. A polyethylene terephthalate (PET) base surface was modified by photograft copolymerization to yield hydrophobic, hydrophilic, anionic and cationic surfaces. Freshly isolated human monocytes were cultured onto the surfaces for periods up to 10 days in the presence or absence of interleukin-4 (IL-4). Semi-quantitative RT-PCR analysis on days 3, 7 and 10 of cell culture revealed that interleukin-10 (IL-10) expression significantly increased in cells adherent to the hydrophilic and anionic surfaces but significantly decreased in the cationic surface adherent monocytes/macrophages. Conversely, interleukin-8 (IL-8) expression was significantly decreased in cells adherent to the hydrophilic and anionic surfaces. Further analysis revealed that the hydrophilic and anionic surfaces inhibited monocyte adhesion and IL-4-mediated macrophage fusion into foreign body giant cells (FBGCs). Therefore, hydrophilic and anionic surfaces promote an anti-inflammatory type of response by dictating selective cytokine production by biomaterial adherent monocytes and macrophages. These studies contribute information necessary to enhance our understanding of biocompatibility to be used to improve the in vivo lifetime of implanted medical devices and prostheses.

Biocompatible Materials↗

Helicity amplitudes A1/2 and A3/2 for the D13(1520) resonance obtained from the gamma-->p-->-->ppi(0) Reaction.

The helicity dependence of the gamma-->p-->-->ppi(0) reaction has been measured for the first time in the photon-energy range from 550 to 790 MeV. The experiment, performed at the Mainz microtron MAMI, used a 4pi-detector system, a circularly polarized, tagged photon beam, and a longitudinally polarized frozen-spin target. These data are predominantly sensitive to the D13(1520) resonance and are used to determine its helicity amplitudes.

Journal Article↗

Observation of structures of chain vortices inside anisotropic high- Tc superconductors.

In order to elucidate the formation mechanism of unconventional arrangements of vortices in high- Tc superconducting thin films at an inclined magnetic field to the layer plane, we investigated the structures of vortex lines inside the films by Lorentz microscopy using our 1-MV field-emission electron microscope. Our observation results concluded that vortex lines are tilted to form linear chains in YBaCu3O(7,8). Vortex lines in the chain-lattice state in Bi2Sr2CaCu2O(8+delta), on the other hand, are all perpendicular to the layer plane, and therefore only vortices lined up along Josephson vortices form chains.

Journal Article↗

In situ hydrogelation of photocurable gelatin and drug release.

We devised an in situ tissue-adhesive, drug-release technology based on a photoreactive gelatin, which allows in situ drug-incorporated gel formation on living tissues and sustained drug release directly on diseased tissues. Styrene-derivatized gelatins, synthesized by condensation reaction of gelatin with 4-vinylbenzoic acid, were photopolymerized in the presence of a water-soluble camphorquinone derivative as a photoinitiator upon visible-light irradiation to form swollen gels. Using albumin as a drug model, gelation characteristics and drug-release characteristics easily were manipulated by material variables, formulation variables, and operation variables. Tissue adhesivity of the gel was superior to that of fibrin glue. The biologic response, which was evaluated by intraperitoneal implantation in rats, showed that the gel was biodegraded and biosorbed, without cytotoxicity, within a few months after implantation. An in situ processable tissue-adhesive local drug release system effectively may be used to help inhibit tumor recurrence.

Adsorption↗

Laparoscopic adrenalectomy for pheochromocytoma: a literature review.

Laparoscopic adrenalectomy has become the standard treatment for benign adrenal tumors, providing minimal invasiveness and early recovery. In the case of pheochromocytomas, special attention should be paid perioperatively to prevent excessive hypertension or hypotension. The protocol should include sufficient preoperative medication with alpha 1 blockers, early ligation of the adrenal vein, and minimal handling of the tumor itself. A literature review of 227 laparoscopic adrenalectomies for pheochromocytomas revealed that the perioperative data, including the operative time, blood loss, and hemodynamic status, were similar or slightly better in the laparoscopic procedures as compared to the open procedures, although the convalescence period was significantly shorter in the laparoscopic surgery. The majority of surgeons prefer the transperitoneal approach for pheochromocytomas, although some authors use the retroperitoneal approach successfully. A comparison of the perioperative data from laparoscopic surgeries for pheochromocytomas versus those for other adrenal tumors showed that the former had slightly higher demands to complete the procedure safely. In the treatment of familial pheochromocytoma due to multiple endocrine neoplasia type 2 or von Hippel-Lindau disease, a cortical-sparing adrenalectomy can be safely performed laparoscopically. In conclusion, laparoscopic adrenalectomy is the standard for small pheochromocytomas, with a high success rate when the procedure is performed by experienced surgeons.

Adrenalectomy↗

The Bacillus subtilis rec-assay: a powerful tool for the detection of genotoxic substances in the water environment. Prospect for assessing potential impact of pollutants from stabilized wastes.

The Bacillus subtilis rec-assay has been specially developed to detect genotoxicity in environmental water samples. The rationale of the B. subtilis rec-assay is based on the relative difference of survival of a DNA repair-recombination proficient strain and its deficient strain, which is interpreted as genotoxicity. This assay method can be very powerful in that it has higher sensitivity for the detection of mutagens in highly polluted waters than other bacterial mutation assays. Hydrophobic fractions from various environmental waters were fractionated by using XAD-2 resins and assayed, targeting the detection of organic genotoxic substances. Genotoxic response was detected in most of them, which revealed that many unknown micropollutants with genotoxicity occur in public water bodies. Positive response was also detected from a treated municipal solid waste (MSW) landfill leachate. Genotoxicity remaining in the treated effluent suggests that genotoxic micropollutants may pass through conventional water treatment processes such as activated sludge treatment process. Without proper control of waste quality and landfill facilities, waste landfill could be a heavy pollution source.

Bacillus subtilis↗

Assessment of cross-reactivity between Japanese cedar (Cryptomeria japonica) pollen and tomato fruit extracts by RAST inhibition and immunoblot inhibition.

BACKGROUND: An association between pollinosis and sensitivity to fruits and vegetables has been reported. Although Japanese cedar (Cryptomeria japonica) pollinosis is one of the most widespread diseases in Japan, there have been no reports demonstrating cross-reactivity between Japanese cedar pollen and other plant food. OBJECTIVE: The aim of this study was to demonstrate cross-reactivity between Japanese cedar pollen and tomato fruit (Lycopersicon esculentum) using RAST inhibition and immunoblot inhibition. METHODS: The RAST and immunoblot inhibition were performed using sera from patients with oral allergy syndrome (OAS) after ingesting fresh tomatoes. We identified some proteins that took part in cross-reactive IgE by the determination of N-terminal amino acid sequences and a homology search through the SWISS-PROT database. RESULTS: In the RAST inhibition, the bindings of IgE from the sera from four out of five (4/5) subjects to Japanese cedar pollen discs were inhibited by more than 50% by preincubation of the serum with tomato fruit extracts. Likewise, the IgE bindings to tomato fruit discs were inhibited more than 50% by Japanese cedar pollen extracts in 3/5 sera. In immunoblot inhibition, IgE binding activities of some protein bands on both membranes were decreased by heterologous inhibitors. However, the combinations of these protein bands involved in cross-reactivity were different between patients. CONCLUSION: We have demonstrated cross-reactivity between Japanese cedar pollen and tomato fruit using RAST inhibition and immunoblot inhibition.

Allergens↗

Elevated levels of soluble CD163 in sera and fluids from rheumatoid arthritis patients and inhibition of the shedding of CD163 by TIMP-3.

The aim of the present study was to evaluate levels of soluble CD 163 in sera and fluids from rheumatoid arthritis (RA) patients and elucidate the mechanism that regulates the shedding of CD163. Levels of soluble CD163 in sera and fluids from RA patients were examined by a sandwich enzyme immunoassay and Western blotting. To determine the effects of tissue inhibitors of metalloproteinase (TIMPs) on the shedding of CD163 from monocytes/macrophages, levels of soluble CD163 in cultures of monocytes/macrophages and the expression of CD163 on monocytes/macrophages in the presence or absence of TIMPs were examined by a sandwich enzyme immunoassay and flow cytometry, respectively. The clinical marker that was most associated with serum levels of soluble CD163 was levels of CRP. TIMP-3, but not TIMP-1 or TIMP-2, inhibited the shedding of CD163 from monocytes/macrophages. It was shown that serum levels of soluble CD163 are a sensitive and reliable marker to monitor activated macrophages in synovitis from RA patients and the results imply that the responsible proteinase for the shedding of CD163 is not a member of the matrix metalloproteinases, but is likely to be a member of ADAMs.

Adult↗

Selective reduction by isolation rearing of 5-HT1A receptor-mediated dopamine release in vivo in the frontal cortex of mice.

Serotonin (5-HT)1A receptors modulate in vivo release of brain monoaminergic neurotransmitters which may be involved in isolation-induced aggressive behavior. The present study examined the effect of isolation rearing on the 5-HT1A receptor-mediated modulation of dopamine (DA), 5-HT and noradrenaline (NA) release in the frontal cortex of mice. The selective 5-HT1A receptor agonist (S)-5-[-[(1,4-benzodioxan-2-ylmethyl)amino]propoxy]-1,3-benzodioxole HCl (MKC-242) increased the release of DA and NA and decreased the release of 5-HT in the frontal cortex of mice. The effect of MKC-242 on DA release was significantly less in isolation-reared mice than in group-reared mice, while effects of the drug on NA and 5-HT release did not differ between both groups. The effect of the other 5-HT1A receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin on cortical DA release was also less in isolation-reared mice than in group-reared mice, and that of the drug on cortical 5-HT release did not differ between both groups. In contrast to MKC-242-induced DA release, amphetamine-induced increase in cortical DA release in vivo was greater in isolation-reared mice. The present findings suggest that isolation rearing enhances the activity of cortical dopaminergic neurons and reduces selectively the 5-HT1A receptor-mediated release of DA in the cortex.

8-Hydroxy-2-(di-n-propylamino)tetralin↗

Growth-associated gene expression profiles by microarray analysis of trophoblast of molar pregnancies and normal villi.

We used microarray analysis to investigate expression profiles of 589 known genes committed to cell growth control to characterize regulatory circuitry for cell proliferation in complete moles (CMs). CMs are characterized by hyperplastic trophoblast and have a high propensity to give rise to choriocarcinoma. Characteristic alterations in gene expression profiles were observed when compared with normal villi. Fifty-seven genes were significantly up-regulated in CMs and involved the Ras-Map kinase 3, Jak-STAT5, and Wnt signal pathways, implicating growth factor or cytokine-mediated signal pathways in the trophoblastic hyperplasia of CMs. Several genes associated with anti-apoptosis, cell structuring, and/or cell attachment were also up-regulated in CMs. In contrast, relatively fewer genes were down-regulated and these involved IGFBPs, versican, interleukin-1, tumor necrosis factor receptor, CD44, and RAD52. Genes identified in this study may elucidate regulation mechanisms of trophoblastic proliferation and mechanisms causing a pathological phenotype in CMs.

Apoptosis↗

Development of high-performance stent: gelatinous photogel-coated stent that permits drug delivery and gene transfer.

Hydrogel-coated metallic stents may provide supplementary functions such as local drug delivery and gene transfer in addition to mechanical dilation function. To this end, we used a photoreactive material consisting of gelatin macromer (multiple styrene-derivatized gelatin) and carboxylated camphorquinone (photo-initiator). A few minutes of visible light irradiation of a stent after dip-coating of an aqueous solution of the photoreactive material resulted in the formation of a homogeneously crosslinked gelatinous layer on the entire exterior surface of the stent. As the metal stent, gold stents under development were used. Rhodamine-conjugated albumin as a model drug or adenoviral vector expressing bacterial beta-galactosidase (AdLacZ) as a model gene were photo-immobilized in the gelatinous gel layer. In vitro experiments using hybrid tubular tissue, which is a self-shrinkaged, vascular smooth muscle cell-incorporated type-I collagen gel, as a vascular model, showed that the immobilized dye-derivatized albumin was released on and permeated into tissues, as observed by confocal laser microscopy, and that the cells transfected with immobilized AdLacZ produced beta-galactosidase up to almost 3 weeks, as observed by x-gal staining. In preliminary in vivo experiments these drug- or adenovirus-immobilized stents were implanted in rabbit common carotid arteries. Within 3 weeks of implantation, drug permeation and gene expression in the vascular tissues were observed, indicating that the gelatinous photogel effectively serves as a matrix or coating for a bioactive stent,which permits drug release as well as gene transfer. This intraluminal approach has the potential to realize drug and gene therapy in atherosclerotic plaque.

Albumins↗

Involvement of benzodiazepine binding sites in an antiaggressive effect by 5-HT(1A) receptor activation in isolated mice.

The effect of the benzodiazepine receptor antagonist flumazenil was examined on an antiaggressive effect of (S)-5-[3-[(1,4-benzodioxan-2-ylmethyl)amino]propoxy]-1,3- benzodioxole HCl (MKC-242), a 5-HT(1A) receptor agonist. MKC-242 (0.1-1.0 mg/kg, p.o.) selectively reduced isolation-induced aggressive behavior in a dose-dependent manner. Flumazenil (10 mg/kg, i.p.) antagonized the antiaggressive effects of MKC-242 and diazepam, although it alone did not affect the behaviors of isolated mice. These findings suggest that a gamma-aminobutyric acid(A) (GABA(A)) receptor system is involved in the antiaggressive effect by 5-HT(1A) receptor activation.

Aggression↗