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Biomedical subjects

T Fujii

Publications and source records attributed to T Fujii.

At least 73 records · Page 4Linked to original sources

Early detection of colorectal cancer using high-magnification chromoscopic colonoscopy.

BACKGROUND: Endoscopic techniques aimed at early detection of colorectal cancer (CRC) and its precursors, permitting targeted in vivo luminal treatments, have been developed by the Japanese since the early 1990s. The introduction of this new technology to the UK (i.e. magnification endoscopes) may permit earlier and more accurate diagnosis. According to Japanese data, magnification chromoscopy can be used to predict histology and invasive depth of cancer, and help in the detection of flat and depressed colonic lesions. Flat and depressed lesions are not purely Japanese phenomena: they exist with a similar incidence in the UK. METHODS: A Medline search was performed for the years 1955-2001 using the following medical subject headings and search methodology: colorectal cancer and colonoscopy or aberrant crypt foci or molecular kinetics or flat/depressed lesions or chromoscopy. RESULTS AND CONCLUSION: Early CRC, in the form of flat or depressed lesions, can be difficult to detect using conventional colonoscopic techniques and penetrate the colonic mucosa deeply. The implications of detecting these lesions in relation to current approaches to the prevention of CRC are profound.

Adenoma↗

The transmembrane form of TNF-alpha drives autoantibody production in the absence of CD154: studies using MRL/Mp-Fas(lpr) mice.

It is generally accepted that the interaction between CD40 and its ligand (CD154) plays a decisive role in contact-dependent help for T and B cells. In CD154-deficient MRL/Mp-Fas(lpr) (MRL/lpr) mice, however, high titres of IgG2a-type autoantibodies against small nuclear ribonucleoproteins (snRNPs) are observed. We successfully isolated two CD154-deficient MRL/lpr Th1 lines, which could provide B cell help for anti-snRNP antibody production. The proliferative responses of the Th1 cell lines were MHC class II (I-Ek)-restricted. Although syngeneic B cell proliferation was induced by Th1 lines in both a contact-dependent and -independent manner, the soluble form of TNF-alpha (sTNF-alpha) was not involved in contact-independent B cell proliferation. On the other hand, both anti-TNF-alpha and TNF-receptor 2 (TNF-R2, p75) monoclonal antibody (MoAb) blocked contact-dependent B cell proliferation, suggesting that the transmembrane form of TNF-alpha (mTNF-alpha)-TNF-R2 co-stimulation participates in B cell activation. Similarly, anti-TNF-alpha and TNF-R2 MoAb inhibited anti-snRNP antibody production in vitro, but anti-CD154 or TNF-R1 MoAb did not. These results indicate that the interaction of mTNF-alpha on activated Th1 cells with TNF-R2 on B cells may be involved in the autoimmunity seen in MRL mice, and that the blockade of CD40-CD154 co-stimulation may not always be able to suppress some Th1-related manifestations of lupus.

Animals↗

Purification and properties of a histidine decarboxylase from Tetragenococcus muriaticus, a halophilic lactic acid bacterium.

AIMS: A histidine decarboxylase from Tetragenococcus muriaticus, a halophilic histamine-producing bacterium isolated from Japanese fermented squid liver sauce, was purified to homogeneity, for the first time. METHODS AND RESULTS: The enzyme was purified 16-fold from cell-free extract by ammonium sulphate precipitation, anion exchange chromatography and hydroxyapatite chromatography. The pure enzyme consisted of two polypeptide chains with molecular mass of 28.8 and 13.4 kDa. The N-terminal amino acid sequences of these polypeptides highly correlated with those of the alpha- and beta-chains of other Gram-positive bacterial histidine decarboxylases. The optimum and stable pH for the enzyme was 4.5-7.0 and 4.0-7.0, respectively. This enzyme did not decarboxylate lysine, arginine, tyrosine, tryptophan and ornithine. The enzyme activity decreased with the addition of NaCl. At pH 4.8, the Vmax and Km values were 16.8 micromol histamine min-1 mg-1 and 0.74 mmol l-1, respectively. CONCLUSIONS: The very similar physiological properties of this enzyme and almost identical N-terminal amino acid sequences to those from other Gram-positive bacteria indicated that this enzyme may be evolutionally highly conserved among Gram-positive bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: Information on this enzyme could be useful for studying the mechanism of histamine accumulation in salted foods. In addition, the N-terminal amino acid sequence can be utilized to design oligonucleotide probes, which may prove valuable in the rapid monitoring of halophilic histamine producers in salted products.

Amino Acid Sequence↗

Occlusal conditions just after the relief of temporomandibular joint and masticatory muscle pain.

When the signs and symptoms of temporomandibular joint disorders (TMD) are present, it is possible that occlusal conditions and mandibular movements are changed. Accordingly, the presence of occlusal interferences may be misjudged. It is therefore reasonable to consider that occlusal conditions should be examined just after the relief of symptoms. The comparison of occlusal conditions in 52 temparomandibular joint (TMJ) pain patients and 27 muscle pain patients with that in 60 asymptomatic controls was made. Occlusal examination in the patients was administered just after the relief of pain by bite plane therapy alone. The only occlusal factor which was associated with pain symptoms was no canine contact on the working side on laterotrusion. It is suggested therefore that further studies as regards this type of interference should be performed.

Adolescent↗

Development of an aggressive depressed cancer in a case of familial adenomatous polyposis.

In 1977, Kariya et al. reported a case of a small depressed cancer in a patient with familial adenomatous polyposis (FAP) raising the possibility that not all cancers in FAP develop from polypoid adenomas. It is now becoming widely recognized that colonic adenomas may appear as flat or depressed lesions. However, colorectal cancers developing in patients with familial adenomatous polyposis (FAP) are still thought to evolve from adenomatous polyps following the polyp-carcinoma sequence. We report the case of a patient with FAP in whom rectal carcinoma developed 23 years after subtotal colectomy and ileorectal anastomosis. We suggest that this malignancy may have developed de novo because of the depressed shape of the lesion and the aggressive growth pattern. This case raises the possibility that carcinomas may not always evolve from polyps in FAP. Aggressive cancers with a depressed appearance should be searched for when surveying the rectal stump in patients with FAP.

Adenocarcinoma↗

A case of hyperplastic polyposis of the colon with adenocarcinomas in hyperplastic polyps after long-term follow-up.

A 66-year-old woman had been receiving follow-up since 1990 for hyperplastic polyposis, which remained unchanged endoscopically and radiologically. In 1999, a small (28 x 22 mm) superficial adenocarcinoma was detected in the ascending colon. Histologically, this was a hyperplastic polyp containing a well-differentiated adenocarcinoma invading into the submucosa. A review of the English and Japanese literature identified 32 cases of "hyperplastic polyposis." In about half of the 32 cases, an adenocarcinoma was also found amongst the hyperplastic polyps. Half of the adenocarcinomas were located in the right colon. Although hyperplastic polyposis is uncommon, it warrants regular surveillance, as it appears to be associated with an increased risk of colorectal cancer.

Adenocarcinoma↗

Molecular characteristics of non-small cell lung cancer.

We used hierarchical clustering to examine gene expression profiles generated by serial analysis of gene expression (SAGE) in a total of nine normal lung epithelial cells and non-small cell lung cancers. Separation of normal and tumor, as well as histopathological subtypes, was evident by using the 3,921 most abundant transcript tags. This distinction remained when only 115 highly differentially expressed tags were used. Furthermore, these 115 transcript tags clustered into groups suggestive of the unique biological and pathological features of the different tissues examined. Adenocarcinomas were characterized by high-level expression of small airway-associated or immunologically related proteins, whereas squamous cell carcinomas overexpressed genes involved in cellular detoxification or antioxidation. The messages of two p53-regulated genes, p21(WAF1/CIP1) and 14-3-3final sigma, were consistently underexpressed in the adenocarcinomas, suggesting that the p53 pathway itself might be compromised in this cancer type. Gene expression patterns observed by SAGE were consistent with results obtained by quantitative real-time PCR or cDNA array analyses by using a total of 43 lung tumor and normal samples. Thus, although derived from only a few tissue libraries, gene expression profiles obtained by using SAGE most likely represent an unbiased yet distinctive molecular signature for the most common forms of human lung cancer.

Base Sequence↗

Dissociation of body-centered and stimulus-centered representations in unilateral neglect.

BACKGROUND: Previous studies on unilateral neglect have shown that there are at least two types of neglect-i.e., body-centered and stimulus-centered neglect. These symptoms suggest that the human brain has at least two different reference frames for processing external space. It is unknown, however, whether these two frames are represented independently in the brain and if so, which areas (or networks) of the brain are responsible for each frame of reference. OBJECTIVE: To determine whether body-centered neglect and stimulus-centered neglect can be dissociated in patients with brain injury. METHODS: New figure discriminative cancellation tasks were designed to simultaneously assess body-centered neglect and stimulus-centered neglect. Two neglect patients with lesions located in different anatomic regions were required to circle every complete figure and to cross out every figure with a missing portion on a sheet of white (29.7 x 42 cm) paper. RESULTS: Patient 1 omitted leftward stimuli on the paper, but the stimuli he found were correctly circled or crossed out. On the other hand, Patient 2 marked stimuli across the paper although he mistakenly circled stimuli that were missing a portion of their left side. Neither patient manifested interaction between the two types of neglect. CONCLUSION: The results of this study clearly showed double dissociation between the two types of neglect. Furthermore, it not only provides evidence that there are two distinct systems of reference frame for external space in the human brain, but also adds new knowledge indicating that these two systems function independently, at least in part.

Aged↗

Heterogeneous expression of Toll-like receptor 4 and downregulation of Toll-like receptor 4 expression on human gingival fibroblasts by Porphyromonas gingivalis lipopolysaccharide.

Porphyromonas gingivalis (P. gingivalis) is implicated in the initiation and progression of periodontitis. Human gingival fibroblasts (HGFs) are the major constituent of gingival connective tissue. P. gingivalis or its components such as lipopolysaccharide (LPS) upregulate the production of various inflammatory cytokines including interleukin (IL)-1 and IL-6 in HGFs. Recently, we demonstrated that the binding of P. gingivalis LPS to Toll-like receptor 4 (TLR4) on HGFs activates various second messenger systems (Biochem. Biophys. Res. Commun. 273, 1161-1167, 2000). In the present study, we examined the level of TLR4 expression on HGFs by flow cytometric analysis (FACS), and studied the levels of IL-1 and IL-6 in the culture medium upon LPS stimulation of HGFs by enzyme-linked immunosorbent assay (ELISA). Upon stimulation by P. gingivalis LPS for 24 h, HGFs that expressed a high level of TLR4 secreted significantly higher levels of IL-1 and IL-6 than HGFs that expressed a low level of TLR4. On the other hand, after stimulation with P. gingivalis LPS for 24 h, the level of TLR4 on the surface of HGFs decreased. These results suggest that the level of TLR4 expression on HGFs reflects the extent of inflammation in the gingival tissue, and that P. gingivalis LPS downregulates TLR4 expression on HGFs. These findings may be used to control inflammatory and immune responses in periodontal disease.

Antibodies, Monoclonal↗

Histamine formation by Tetragenococcus muriaticus, a halophilic lactic acid bacterium isolated from fish sauce.

We examined histamine formation in cultures of Tetragenococcus muriaticus, a halophilic lactic acid bacterium isolated from fish sauce. T. muriaticus formed histamine in low acidity (pH 5.8), O2 limiting conditions with optimal NaCl and glucose concentrations of 5-7% (w/v) and above 1%, respectively. Histamine formation could not be prevented even at 20% (w/v) NaCl, indicating that NaCl could not prevent histamine formation by this bacterium. A conspicuous amount of histamine accumulated only during the late stationary phase regardless of the growth conditions. Studies of cell suspension experiments confirmed the results obtained from cultured cells.

Animals↗

Antibodies against neural, nuclear, cytoskeletal, and streptococcal epitopes in children and adults with Tourette's syndrome, Sydenham's chorea, and autoimmune disorders.

BACKGROUND: Some cases of Tourette's syndrome (TS) are hypothesized to be caused by autoantibodies that develop in response to a preceding group A beta hemolytic streptococcal infection. METHODS: To test this hypothesis, we looked for the presence ot total and IgG antibodies against neural, nuclear, cytoskeletal and streptococcal epitopes using indirect immunofluorescent assays and Western blot techniques in three patient groups: TS (n = 81), SC (n = 27), and a group of autoimmune disorders (n = 52) and in normal controls (n = 67). Subjects were ranked after titrations of autoantibodies from 0 to 227 according to their level of immunoreactivity. RESULTS: TS patients had a significantly higher mean rank for total antineural and antinuclear antibodies, as well as antistreptolysin O titers. However, among children and adolescents, only the total antinuclear antibodies were increased in TS patients compared to age matched controls. Compared to SC patients, TS patients had a significantly lower mean rank for total and IgG class antineural antibodies, significantly lower IgG class anticytoskeletal antibodies, and a significantly higher rank for total antinuclear antibodies. Compared to a mixed group of autoimmune disorders, the TS patients had a significantly lower mean rank for total and IgG class antineural antibodies, total and IgG class antinuclear antibodies, IgG class anticytoskeletal antibodies, and a significantly higher rank for antistreptococcal antibodies. CONCLUSIONS: TS patients had significantly higher levels of total antineural and antinuclear antibodies than did controls. Their relation to IgG class antineural and antinuclear antibodies, markers for prior streptococcal infection, and other clinical characteristics, especially chronological age, was equivocal.

Adolescent↗

Enhanced myocardial angiogenesis by gene transfer with transplanted cells.

UNLABELLED: BACKGROUND The combination of myocardial cell transplantation and angiogenic gene transfer may improve postinfarction left ventricular (LV) perfusion. We evaluated the angiogenic effect of heart cells transfected with vascular endothelial growth factor (VEGF) and transplanted into a myocardial scar. METHODS AND RESULTS: Donor rat heart cells were transfected with plasmids encoding VEGF(165) and green fluorescence protein. Syngeneic adult rats underwent LV cryoinjury to create a transmural scar. Three weeks later, 4x10(6) transfected heart cells (n=14), untransfected heart cells (n=13), or culture medium (n=16) were transplanted into the center of the scar. After 5 weeks, LV function, quantitative histology, and regional blood flow were evaluated. Plates of heart cells transfected with VEGF(165) produced 6.1 times more intracellular VEGF than nontransfected cells. Capillary density (mean+/-SEM) per high-power field in the center of the myocardial scar was 1.1+/-0.02 in control rats, 3.9+/-0.11 in untransfected rats, and 6.3+/-0.11 in transfected rats (P=0.0002). Capillary density in the border zone around the scar was 1.9+/-0.03 in control rats, 6.4+/-0.10 in untransfected rats, and 8.7+/-0.16 in transfected rats (P=0.004). Regional blood flow within the scar was 8.8+/-0.8% of normalized flow in control hearts, 10.4+/-0.7% in hearts transplanted with untransfected cells, but 17.6+/-1.2% in hearts transplanted with transfected cells (P=0.03 versus control, P=0.07 versus nontransfected). There was no difference in LV function attributable to transplantation with transfected cells at the time point studied. CONCLUSIONS: Transplantation of heart cells transfected with VEGF induced greater angiogenesis than transplantation of unmodified cells. Combined gene transfer and cell transplantation strategies may improve postinfarction LV perfusion and function.

Animals↗

Analysis of E6 variants of human papillomavirus type 33, 52 and 58 in Japanese women with cervical intraepithelial neoplasia/cervical cancer in relation to their oncogenic potential.

The variation of the E6 region of human papillomavirus type 16 (HPV16) is associated with a high risk for cervical carcinogenesis. To see whether the same is the case with HPV33, 52 and 58, known to have high homology with HPV16, we analyzed the E6 sequence variation of these HPVs in 107 Japanese women with cervical intraepithelial neoplasia (CIN) or invasive cervical cancer (ICC): 20 HPV33-positive, 46 HPV52-positive and 41 HPV58-positive cases. HPV33 variants were more frequently observed in CINs I/II than in CIN III/ICCs (71% (5/7) versus 15% (2/13), P=0.02). In HPV52-positive cases, a single E6 variant was detected in 98% of the cases, whereas the prototype accounted for 98% of HPV58-positive cases. In summary, the distribution of E6 variants is different among HPV types tested, suggesting a link between E6 variation and oncogenic potential being type-specific.

Female↗

Cytokines involved in the systemic inflammatory response induced by exposure to particulate matter air pollutants (PM(10)).

Elevated levels of ambient particulate matter (PM(10)) have been associated with increased cardiopulmonary morbidity and mortality. We previously showed that the deposition of particles in the lung induces a systemic inflammatory response that includes stimulation of the bone marrow. This marrow response is related to mediators released by alveolar macrophages (AM) and in this study we measured cytokines produced by human AM exposed to ambient particles of different composition and size. Identified cytokines were also measured in the circulation of healthy young subjects exposed to air pollutants during the 1997 Southeast Asian forest fires. Human AM were incubated with particle suspensions of residual oil fly ash (ROFA), ambient urban particles (EHC 93), inert carbon particles, and latex particles of different sizes (0.1, 1, and 10 microm) and concentrations for 24 h. Tumor necrosis factor-alpha (TNF-alpha) increases in a dose-dependent manner when AM were exposed to EHC 93 particles (p < 0.02). The TNF response of AM exposed to different sizes of latex particles was similar. The latex (158 +/- 31%), inert carbon (179 +/- 32%), and ROFA (216 +/- 34%) particles all show a similar maximum TNF response (percent change from baseline) whereas EHC 93 (1,020 +/- 212%, p < 0.05) showed a greater maximum response that was similar to lipopolysaccharide (LPS) 1 microg/ml (812 +/- 320%). Macrophages incubated with an optimal dose of EHC 93 particles (0.1 mg/ml) also produce a broad spectrum of other proinflammatory cytokines, particularly interleukin (IL)-6 (p < 0.01), IL-1 beta (p < 0.05), macrophage inflammatory protein-1 alpha (MIP-1 alpha) (p < 0.05), and granulocyte macrophage colony-stimulating factor (GM-CSF) (p < 0.01) with no difference in concentrations of the anti-inflammatory cytokine IL-10 (p = NS). Circulating levels of IL-1 beta, IL-6, and GM-CSF were elevated in subjects exposed to high levels of PM(10) during an episode of acute air pollution. These results show that a range of different particles stimulate AM to produce proinflammatory cytokines and these cytokines are also present in the blood of subjects during an episode of acute atmospheric air pollution. We postulate that these cytokines induced a systemic response that has an important role in the pathogenesis of the cardiopulmonary adverse health effects associated with atmospheric pollution.

Aged↗

Decreased acetylcholine content and choline acetyltransferase mRNA expression in circulating mononuclear leukocytes and lymphoid organs of the spontaneously hypertensive rat.

It has been confirmed that the neurotransmitter acetylcholine (ACh) is present in blood; it is synthesized in T-lymphocytes by choline acetyltransferase (ChAT) and released upon T-lymphocyte activation. Both muscarinic and nicotinic ACh receptors have been identified on lymphocytes isolated from thymus, lymph node, spleen and blood, and their stimulation by muscarinic and nicotinic agonists elicits a variety of functional and biochemical effects, providing a strong argument that ACh synthesized and released from T-lymphocytes acts as an autocrine and/or paracrine factor regulating immune function. In the present study, we compared ACh levels in the blood, circulating mononuclear leukocytes (MNLs), thymus and spleen of spontaneously hypertensive rats (SHRs), which exhibit immune deficiencies related to the emergence of natural thymocytotoxic autoantibody, age-related decline of T-cell function and morphological changes in immune organs, with ACh levels in age-matched, normotensive Wistar Kyoto rats. In each case, ACh levels in 5-, 10- and 20-week-old SHRs were significantly lower than in WKYs. ChAT mRNA expression in MNLs was also significantly depressed in the SHRs. These results suggest that diminished synthesis and release of ACh from MNLs into blood and lymphoid organs likely reflects an immune deficiency related to T-cell dysfunction.

Acetylcholine↗