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Biomedical subjects

K Saito

Publications and source records attributed to K Saito.

At least 19 recordsLinked to original sources
PubMed2006

Different effects of high molecular weight sodium hyaluronate and NSAID on the progression of the cartilage degeneration in rabbit OA model.

OBJECTIVE: We examined the effects of nonsteroidal anti-inflammatory drug (NSAID) and intra-articular injections of sodium hyaluronate (HA) on cartilage degeneration in rabbit knee osteoarthritis (OA) model induced by partial meniscectomy. METHODS: Loxoprofen sodium (LOX) was used as the NSAID, administered p.o. once daily for 14 days at a dose of 4 mg/kg, starting from the day of meniscectomy. Suvenyl(SVE) was used as the high molecular weight HA, injected intra-articularly into injured knee every 3 days from the day of surgery. The effect on pain was assessed by an Incapacitance Tester, and the damage of cartilage was evaluated by visual assessment and histopathology at 14 days after the surgery. RESULTS: Hind paw weight bearing on the injured paw decreased time-dependently in the control group. In other three groups, the decrease of hind paw weight distribution was suppressed, demonstrating an analgesic effect. Visible damage and histopathological findings of cartilage degeneration were evident in the cartilages of the control group at day 14. In the SVE group, the damaged cartilage area decreased and cartilage degeneration was ameliorated. In contrast, in the LOX group, the cartilage degeneration was augmented compared with the control group. And, this exacerbated cartilage degeneration induced by LOX was reversed by the concomitant use of SVE. CONCLUSION: Our data show that the treatment with high molecular weight HA from earlier stage is strongly recommended to preserve the structure of cartilage.

Adjuvants, Immunologic↗
PubMed2006

Rheumatoid synovial endothelial cells produce macrophage colony-stimulating factor leading to osteoclastogenesis in rheumatoid arthritis.

OBJECTIVES: Periarticular osteoporosis and joint destruction are major complications in rheumatoid arthritis (RA), caused by osteoclast-mediated bone resorption. However, the mechanisms of monocyte/osteoclast maturation and role of RA endothelial cells (RAECs) in the control of osteoclastogenesis remain unclear. The present study was designed to determine the most important factors that influence monocyte accumulation and osteoclast formation among the many factors produced by RAEC. METHODS: We analysed the expression profiles of various genes in human endothelial cells from various organs (RA synovium, umbilical vein, skin, liver sinusoid, renal glomerulus and brain) using oligonucleotide microarrays. Specifically, up-regulated gene in RAECs was assessed by real-time quantitative polymerase chain reaction, enzyme-linked immunosorbent assay and immunostaining of RA synovia. Migration of monocytes was assessed by the chemotactic chamber EZ-TAXIScan. Tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cell (MNC) formation was observed by microscopy. RESULTS: Among many epithelial-expressed factors, macrophage colony-stimulating factor (M-CSF) gene was abundantly expressed specifically in RAECs. Genes of fibroblast growth factor-2, interleukin-6 and osteoprotegerin were also overexpressed in RAECs. Migration of monocytes and osteoclast formation in co-cultures promoted by culture supernatants of RAECs were inhibited by M-CSF neutralizing antibody. CONCLUSIONS: M-CSF produced by RAECs is involved in osteoclastogenesis from monocytes, migration and TRAP-positive MNC formation.

Arthritis, Rheumatoid↗
PubMed2006

Japanese adult male voxel phantom constructed on the basis of CT images.

A Japanese adult male voxel (volume pixel) phantom (hereinafter referred to as the JM phantom) was constructed on the basis of CT images of a healthy Japanese adult male volunteer. Body characteristics of the JM phantom were compared with those of a voxelised MIRD5 type phantom and a Japanese adult male voxel phantom which was previously developed. The voxel size of the JM phantom is 0.98 x 0.98 x 1 mm(3). The shapes of the organs of the JM phantom, even for small or complicated organs, such as thyroid and stomach, are more realistically reproduced as compared with the previous Japanese voxel phantom (voxel size: 0.98 x 0.98 x 10 mm(3)). Photon self-absorbed fractions (self-AFs) for brain, kidneys, spleen, pancreas, thyroid and urinary bladder wall of JM were evaluated and were compared with those of the other phantoms. In consequence, it was suggested that the mass, shape and thickness of organs are important factors for the determination of self-AFs.

Adult↗
PubMed2006

A novel endoscopic marker: safety experiments in the rat stomach.

BACKGROUND AND STUDY AIMS: The study aimed to assess a newly developed endoscopic marker designed to cause only minor inflammatory reactions. MATERIALS AND METHODS: Chitosan and carbon powder were used in the marker substance. The product was a viscoelastic solution, which was injected into the submucosa in rat stomach walls. The tissue reactions were then examined histopathologically. The structure of the injected marker substance was examined with electron microscopy into rat stomach walls. India ink, which is currently used as an endoscopic marker, served as the control. RESULTS: Histopathological examination showed that inflammatory reactions with the novel agent were remarkably mild in the rat organs, while submucosally applied india ink caused severe inflammation in situ. The electron-microscopic findings showed that the carbon particles used were completely spherical in shape and that the carbon in the marker substance was entrapped in the chitosan networks. The india ink was shown to consist of a mixture of fine carbon particles and adhesive additives. CONCLUSIONS: The chitosan-carbon solution appears to be a promising endoscopic marker substance, causing significantly reduced inflammation.

Animals↗
PubMed2006

Overexpression of stathmin in oral squamous-cell carcinoma: correlation with tumour progression and poor prognosis.

Stathmin is an intracellular phosphoprotein that is overexpressed in a number of human malignancies. Our previous study using proteomic profiling showed that significant upregulation of stathmin occurs in oral squamous-cell carcinoma (OSCC)-derived cell lines. In the current study, to determine the potential involvement of stathmin in OSCC, we evaluated the state of stathmin protein and mRNA expression in OSCC-derived cell lines and human primary OSCCs. A significant increase in stathmin expression was observed in all OSCC-derived cell lines examined compared to human normal oral keratinocytes. In immunohistochemistry, 65% of the OSCCs were positive for stathmin, and no immunoreaction was observed in corresponding normal tissues. Real-time quantitative reverse transcriptase-polymerase chain reaction data were consistent with the protein expression status. Moreover, stathmin expression status was correlated with the TNM stage grading. Furthermore, we found a statistical correlation between the protein expression status and disease-free survival (P=0.029). These results suggest that expression of stathmin could contribute to cancer progression/prognosis, and that stathmin may have potential as a biomarker and a therapeutic target for OSCC.

Aged↗
PubMed2006

In silico assessment of gene function involved in cysteine biosynthesis in Arabidopsis: expression analysis of multiple isoforms of serine acetyltransferase.

In plants, the inorganic sulfur is first fixed into cysteine by the cysteine biosynthetic pathway. This biosynthetic pathway of cysteine involves several enzymatic reactions. In Arabidopsis thaliana, multiple isoforms seem to participate in each enzymatic step for cysteine biosynthesis. To obtain more insights on the specific role of each isoform involved in the cysteine biosynthesis, in silico analysis of these isoforms using Arabidopsis expressed sequence tags (EST) database was carried out. This EST database analysis revealed distinct population distribution of ESTs among multiple isoforms, suggesting that each isoform has its particular expression pattern, presumably associated with its specific role in cysteine biosynthesis. As another in silico analysis, co-expression analysis of genes involved in sulfur metabolism in Arabidopsis was performed using a public transcriptome database of DNA microarrays. This co-expression analysis also suggested specific function and co-regulation of some isoform genes for cysteine biosynthesis by consideration on the clustering of co-expressed genes. From the results of sensitivity to feedback regulation, subcellular localization and expression of mRNA analyses, each serine acetyltransferase (SATase) isoform seems to have its specific role for cysteine biosynthesis. Similar expression patterns were observed between the experimental results of expression data for SATase isoforms and the in silico results of "digital northern" analysis using EST database.

Arabidopsis↗
PubMed2006

Semen quality in a Giant Panda (Ailuropoda melanoleuca) in relation to estrus of a nearby resident female panda.

Semen quality was determined in a sexually mature male Giant Panda, electroejaculated 13 times during a 5-year interval, before, during and after estrus of a female Giant Panda housed nearby. Testis volume and plasma testosterone concentrations were also measured. Mean testis volumes were 1223.0 +/- 64.7(S.E.M.)cm3 (before estrus), 1213.2 +/- 218.2 cm3 (during estrus), and 1360.2+/-160.4 cm3 (after estrus). Compared to before and during estrus in the female, testis volume decreased 70 days after estrus and there was no projectile ejaculation. The mean semen volume and sperm count were 2.2+/-0.7 mL and 8.3 +/- 3.1 x 10(8) before estrus, 2.4 +/- 0.9 mL and 5.7 +/- 0.9 x 10(8) during estrus, and 1.3 +/- 0.3 mL and 8.1 +/- 1.7 x 10(8) after estrus, respectively. The semen volume, sperm count, and testis volume markedly differed from 90 days before estrus until 66 days after estrus, whereas no marked differences in sperm motility, sperm viability, and proportion of morphologically abnormal spermatozoa were observed. Plasma testosterone concentrations were elevated both before and during estrus (0.62 +/- 0.23 ng/mL and 0.95 ng/mL), but decreased substantially after estrus (0.20 +/- 0.0 ng/mL). We inferred that spermatogenesis was active in this male panda from approximately 3 months before estrus to 2 months after estrus in the adjacent female.

Animals↗
PubMed2006

Adenoviral GDNF gene transfer enhances neurofunctional recovery after recurrent laryngeal nerve injury.

To assess the possibility of gene therapy for recurrent laryngeal nerve (RLN) injury, we examined functional and histological recovery after glial cell line-derived neurotrophic factor (GDNF) gene transfer in a rat RLN crush model. Adenoviral vector encoding beta-galactosidase gene (AxCALacZ) or human GDNF gene (AxCAhGDNF) was injected into the crush site of the RLN. Neurons in the nucleus ambiguus on the crushed side were labeled with X-gal or GDNF immnohistochemistry after AxCALacZ or AxCAhGDNF injection. Reverse transcription-polymerase chain reaction analysis revealed expression of human GDNF mRNA transcripts in brainstem tissue containing the nucleus ambiguus on the crushed side after AxCAhGDNF injection. Animals injected with AxCAhGDNF displayed significantly improved motor nerve conduction velocity of the RLN and recovery rate of vocal fold movement at 2 and 4 weeks after treatment as compared to controls. AxCAhGDNF-injected animals showed a significantly larger axonal diameter and improved remyelination in crushed RLN as compared to controls. Adenoviral GDNF gene transfer may thus promote laryngeal function recovery after RLN injury. Inoculation of adenoviral vector containing the GDNF gene at the site of damage soon after nerve injury may assist patients with laryngeal paralysis caused by nerve injury during head and neck surgery.

Adenoviridae↗
PubMed2006

CyberKnife stereotactic radiotherapy for patients with malignant glioma.

OBJECTIVE: The CyberKnife is a new frameless image-guided radiosurgical modality. The authors report on their experience using the CyberKnife in 25 patients with malignant gliomas. METHODS: Twenty-five patients with histologically proven malignant gliomas (18 glioblastoma: GB, 7 anaplastic astrocytoma: AA) were treated with the CyberKnife at Konan St. Hill Hospital between June 1998 and November 2002. CyberKnife therapy was performed on 44 lesions (31 GB lesions, 13 AA lesions) in the 25 patients. The median target volume was 19.1 mL (range: 0.3 - 90.2). The median prescribed dose was 20.3 Gy (range: 13.9 - 26.4). Patient-, tumor-, and treatment-related variables were analyzed by univariate analysis, and survival curves were generated by the Kaplan-Meier product limit. RESULTS: In the 18 GB patients, the median survival after diagnosis was 20.7 months (82.6 weeks) with a mean follow-up of 85.7 weeks. Of the 7 AA patients, 6 were alive at the time of analysis with follow-up periods ranging from 11.4 to 52.8 months. Patients younger than 70 years had a median survival after diagnosis of 37.1 months, compared to 12.4 months for older patients (p = 0.003). Similarly, patients with well-controlled lesions had a median survival after diagnosis of 39.8 months compared to 16.0 months for those with uncontrolled lesions (p = 0.031). Late delayed radiation necrosis was seen in 1 GB patient. No other patient suffered acute or delayed neurological morbidity after CyberKnife therapy. CONCLUSION: This is the first report of CyberKnife stereotactic radiotherapy applied to the treatment of malignant gliomas. The frameless and painless CyberKnife stereotactic radiotherapy has the potential to be as useful for treatment of malignant glioma as other radiosurgical modalities.

Adult↗
PubMed2006

The role of cyberknife radiosurgery/radiotherapy for brain metastases of multiple or large-size tumors.

OBJECTIVE: Focused, highly targeted radiosurgery and fractionated radiotherapy using the Cyberknife are useful treatments for multiple or large metastases. Here we present our results of Cyberknife radiosurgery for 71 patients with 148 metastatic brain lesions. METHODS: There were 32 women and 39 men with a median age of 63 (range: 30-88) years. Radiographic follow-up was available for 60 patients with 104 lesions. The mean and median initial volumes of the tumor per lesion were 6.6 and 2.9 cm(3) (range: 0.1-53.2 cm(3)), respectively, at the time of the initial Cyberknife treatment. Forty patients (56%) had a single lesion, and 31 (44%) had multiple lesions (range: 2-7) at initial treatment. The number of fractions ranged from 1 to 3, and forty (27%) of 148 lesions were treated by a fractionated course of Cyberknife therapy. The mean marginal dose was 20.2 Gy (range 7.8-30.1 Gy, median: 20.7 Gy). RESULTS: At 44 weeks of median follow-up, there were no permanent symptoms resulting from radiation necrosis. Overall 6-month and 1-year survival rates were 74% and 47%, respectively, and the median survival time was 56 weeks. The Karnofsky performance score and extracranial metastasis were significant prognostic factors at 6 months and 1 year, respectively, in both univariate and multivariate analyses. Age or multiple metastases did not influence prognosis at 6 months and 1 year. Local control was achieved in 83% (86 lesions). After additional radiosurgical or surgical salvage, no patient died as a result of intracranial disease. Twenty-five patients developed 92 new metastases (range 1-13) outside of the treated lesions with 22.4 weeks of median follow-up. Among them, 21 patients (84 lesions) were treated by salvage Cyberknife. CONCLUSION: Despite the inclusion of an unfavorable group of patients with large tumors, our results for survival and tumor control rates are comparable to those of published series. The Cyberknife provides the advantage of allowing for fractionated treatment to multiple or large-size tumors.

Adult↗
PubMed2006

Levan (beta-2, 6-fructan), a major fraction of fermented soybean mucilage, displays immunostimulating properties via Toll-like receptor 4 signalling: induction of interleukin-12 production and suppression of T-helper type 2 response and immunoglobulin E production.

BACKGROUND: Products from the fermentation process of soybeans by Bacillus subtilis (natto) have been shown to possess anti-tumour and immunomodulatory activities. However, the formulations previously examined were not chemically pure, and this is a major limitation for elucidation of the molecular mechanisms for their activities. OBJECTIVE: In order to determine which components in soybean mucilage exert immunostimulatory activities, we examined the activities of their purified forms in vitro and in vivo in mice. METHODS: B. subtilis (natto) and fractions including levan and poly-gamma-glutamic acid (gamma-PGA) from fermented soybean mucilage were prepared. Levels of cytokine production by mouse macrophage cells after treatment with the fractions were measured by means of ELISA. In vivo effect of levan delivered intragastrically on ovalbumin (OVA)-specific T-helper type 2 (Th2) response with IgE production was examined in BALB/c mice that had been immunized intraperitoneally with OVA. Results Levan but neither gamma-PGA nor killed B. subtilis (natto) was found to exert strong activity to induce production of IL-12 p40 and TNF-alpha by macrophage cell lines in vitro. RESULTS: of experiments using Toll-like receptor (TLR) 4-deficient mice and TLR4-transfected human cell line indicated that TLR4 is involved in pattern recognition of levan. Oral administration of levan in vivo significantly reduced the serum levels of OVA-specific IgE and Th2 response to OVA in mice immunized with OVA. CONCLUSION: Levan is an immunostimulatory moiety in products from the fermentation process of B. subtilis (natto) and may be useful for prevention of allergic disorders with IgE production.

Adjuvants, Immunologic↗
PubMed2006

Cloning and expression analysis of takeout/JHBP family genes of silkworm, Bombyx mori.

A Bombyx EST cDNA database was searched using the Drosophila takeout gene and nine cDNAs were obtained. The homology search suggested that these genes are widespread in insects and organize a large gene family, and that they have hydrophobic ligands. A phylogenetic tree indicated that the genes are first divided into two large groups, juvenile hormone binding protein and other protein genes, and the latter group diversified within a short time at an early stage. The expression study of five Bombyx genes indicated that they are expressed in various tissues and are regulated by development and feeding conditions. The Bombyx genes might have roles related to the regulation of metabolism, growth or development related to nutritional conditions.

Amino Acid Sequence↗
PubMed2006

True carcinosarcoma of the esophagus.

Most esophageal carcinosarcomas are diagnosed as so-called carcinosarcoma, in which individual elements may be derived from a single common ancestor cell, and there have been a few reports describing true carcinosarcoma originating from two individual stem cells. We describe a case of esophageal carcinosarcoma exhibiting neoplastic osteoid formation. Immunoreactivity for vimentin and p53 was limited to only the sarcomatous component and was absent in the carcinomatous component. Furthermore, a point mutation in exon 7 of the p53 gene was observed only in the sarcomatous component. Both sarcoma and carcinoma cells distinctively metastasized to different lymph nodes. These observations led us to diagnose the esophageal tumor as a true carcinosarcoma.

Carcinosarcoma↗
PubMed2006

Morules and morule-like features associated with carcinomas in various organs: report with immunohistochemical and molecular studies.

BACKGROUND: Morules have been reported in pulmonary blastoma (PB), well differentiated fetal adenocarcinoma of the lung (WDFA), and uterine endometrioid carcinoma (EC), and rarely in other carcinomas. beta Catenin gene mutation has been associated with morule formation. AIMS: To compare and clarify the cellular characteristics of morules in carcinomas in various organs and show that morules are distinct from epithelial cellular nodules. METHODS: Twenty tumours were studied: two PBs, three WDFAs, three papillary lung adenocarcinomas, 11 ECs, and one papillary thyroid carcinoma. Numerous epithelial cell, oncofetal, and neuropeptide antibodies were used for immunohistochemistry. beta Catenin gene mutation was investigated. RESULTS: Morules in PBs and ECs were uniform cell clusters distinct from squamous differentiation. All were immunonegative for epithelial cell and oncofetal antigens, but those in ECs were positive for neurone specific enolase gamma (NSEgamma). Synaptophysin, encephalin, and somatostatin were sporadically immunopositive in PB morules. Morules were not seen in the other carcinomas and WDFAs, although morule-like features closely resembling morules histopathologically were seen. These were positive for epithelial cell and oncofetal antigens, and showed squamous differentiation. Their nuclei were more atypical and slightly larger than those in morules. Morule-like features were seen in WDFAs. beta Catenin gene mutation was demonstrated in one EC and PB, and in two WDFAs. CONCLUSION: Morules were non-epithelial cell clusters showing neuronal differentiation. There were two types: endometrioid type, expressing NSEgamma, and blastoma type, expressing neuropeptides. In contrast, similar morule-like features were epithelial nodules. Although the number of cases was small, the presence of morules showed no clear prognostic correlations.

Adenocarcinoma↗
PubMed2006

Transfer of hydrophobic contaminants in urban runoff particles to benthic organisms estimated by an in vitro bioaccessibility test.

An in vitro bioaccessibility test was applied for assessing the transfer of polycyclic aromatic hydrocarbons (PAHs) present in road dust, into benthic organisms living in a receiving water body. The road dust is supposed to be urban runoff particles under wet weather conditions. Sodium dodecyl sulfate (SDS) solution was used as a hypothetical gut fluid. Pyrene, fluoranthene and phenanthrene were the main PAH species in the SDS extractable fraction of road dust, as well as the whole extract. Benzo(ghi)perylene showed relatively low concentrations in the SDS extract in spite of a high concentration in the original dust. The PAH composition in benthic organisms (polychaetes) did not correspond with that of the surrounding sediment and the PAHs detected were also detected in high concentrations in the SDS extract of road dust. When testing the toxicity of the extracted contaminants by a standardised algal toxicity test, SDS extracts of a detention pond sediment showed higher toxicity than the pore water of the corresponding sediment. Sediment suspension showed a comparative toxicity with 0.1% SDS extract. From the results, the in vitro bioaccessibility test seems more suitable to evaluate the exposed contaminants than the traditional organic solvent extraction method and the SDS extracted fraction is applicable to toxicity tests reflecting the digestive process.

Animals↗