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T Takakuwa

Publications and source records attributed to T Takakuwa.

At least 19 recordsLinked to original sources
PubMed2006

Toxicity assessment of treated wastewater using cultured human cell lines.

Bioassay using cultured human cell lines was applied to an effluent of a wastewater treatment plant (WWTP) in Sapporo to assess their toxicity, and in order to investigate the fate of toxicity in the WWTP, bioassay of the water samples from several points in WWTP (influent, effluent, return flow from thickener, from dewatering process and from incineration process) was performed. We also applied bioassay to the mixture of the activated sludge from the investigated plant and artificial sewage. These results showed that the toxicity of the effluent was more intensive than the influent, and organic matter released from activated sludge bacteria during their decay process contributed to the increase of toxicity in the effluent.

Biological Assay↗
PubMed2006

Epigenetic regulation of the expression of the novel stem cell marker CDCP1 in cancer cells.

CDCP1 is a novel stem cell marker that is expressed in several types of cancer. The mechanisms by which CDCP1 expression is regulated, and the clinical implications of this marker, have not been clarified. In this report, we examine the epigenetic regulation of CDCP1 expression in cell lines and clinical samples from patients with breast cancer. Many CpG sequences were localized around the transcription initiation site of CDCP1. These CpG motifs were found to be poorly methylated in cell lines with high levels of CDCP1 expression and heavily methylated in cell lines with low levels of CDCP1 expression. The in vitro methylation of CpG sites decreased CDCP1 promoter activity, and the addition of a demethylating reagent restored activity. In 25 breast cancer samples, an inverse correlation was noted between the CDCP1 expression level and the proportion of methylated to non-methylated CpG sites. Tumours with high-level CDCP1 expression showed higher levels of proliferation, as revealed by immunohistochemical detection of the MIB-1 antigen, than tumours with low-level CDCP1 expression. These findings indicate that the expression of CDCP1 is regulated by methylation of its promoter region in tumours. CDCP1 expression may prove to be useful in the further characterization of cancers.

Adenocarcinoma↗
PubMed2005

Biological activity in the composting reactor of the bio-toilet system.

The bio-toilet is becoming commercially available and it is actually used in Japan in public parks, sightseeing areas, and households; however, the biological activity in the system during degradation of toilet wastes, particularly faeces, is unknown. Thus, in this study activity of microorganisms in the bio-toilet system during degradation of faeces was assessed through the quantification of reductions in total solids (TS), volatile solids (VS), and chemical oxygen demand (COD) during batch tests in laboratory-scale composting reactors. Additionally, the fate of nitrogen and its transformation processes in such reactors were evaluated. TS, VS, and COD reductions were on the order of 56%, 70%, and 75%, respectively, irrespective of the organic loading regarded. Total nitrogen (T-N) reductions quantified 94%, regardless of the organic loading. Furthermore, all T-N reductions observed during composting were equivalent to the NH(3)-N released from the reactor, i.e., 94% of ammonia was lost.

Aerobiosis↗
PubMed2005

Organic matter released from activated sludge bacteria cells during their decay process.

Organic matter released from activated sludge bacteria is a considerable issue in the wastewater reclamation process. In this study, we focused 2-keto-3-deoxyoctulosonic acid in the Lipopolysaccharide existed in the gram-negative bacterial cell wall as an index of organic matter released from bacteria, and investigated the fate of 2-keto-3-deoxyoctulosonic acid in the aerated and ultrasonicated activated sludge samples. The results shows 1) 2-keto-3-deoxyoctulosonic acid concentration in the hydrolyzed sample was higher than non-hydrolyzed sample, and this implied that 2-keto-3-deoxyoctulosonic acid existed in the water phase as a monomer and also as a polymer such as Lipopolysaccharide form and their fragments; 2) the value of (2-keto-3-deoxyoctulosonic acid)/(dissolved organic carbon) ratio did not change in the sludge sonication process and was approximately 0.0006, on the other hand, in the bacteria decay process, the ratio varied from zero to approximately 0.0012; 3) the linear relationship was observed between the degraded heterotrophic biomass and the generated 2-keto-3-deoxyoctulosonic acid; and 4) 2-keto-3-deoxyoctulosonic acid might be considered as an index of organic matter originated from activated sludge bacteria cell.

Gram-Negative Bacteria↗
PubMed2005

Role of hydrophilic organic matter on developing toxicity in decay process of activated sludge.

It is known that the toxicity of effluent is more intensive than that of influent in the activated sludge process. In this study, we applied bioassay using cultured human cell lines to the decay process of activated sludge to evaluate the toxicity of organic matter generated and/or released from activated sludge bacteria. We also applied this bioassay to hydrophilic fraction of samples. The bioassay results showed that: (1) the variation in the dose-response relation obtained from assay with original samples was observed during decay; (2) on the other hand, the response curves of only hydrophilic fraction at each time show the same relationship between TOC and viability of MCF7 cells; (3) this trend was confirmed by plotting the time course of EC50. These results imply that: (1) the hydrophilic organic matter controlled for developing toxicity during decay process of activated sludge; and (2) the character of hydrophilic organic matter is not changed during the experimental period.

Anion Exchange Resins↗
PubMed2004

Mathematical model for describing reactions of residual chlorine with organic matter in reclaimed wastewater.

Among several applications of urban wastewater reuse, use of reclaimed wastewater to sustain stream flows has become attractive in the urban area. Since these rivers are used for recreational purposes and for restoring aquatic eco-system, the adequate control of residual chlorine is essential. Mathematical model for describing reactions between residual chlorine and organic matter in reclaimed wastewater has been developed. The model considers the effect of molecular weight distribution of organic matter on the reaction rate. Lab-scale experiments were performed to estimate reaction rates constants and to examine their temperature dependency. The experiments showed that 1) the smaller organic matter gave the larger reaction rate; 2) temperature effect on reaction rate was described by the Arrhenius formula; 3) decline of free chlorine had more temperature dependency than combined chlorine. The comparison of computed results with data from lab-scale experiments confirmed the validity of the model. We used the one-dimensional dispersion model with proposed reaction model and examined the seasonal variation of residual chlorine profile along the river sustained by reclaimed wastewater in Sapporo. Simulation showed that seasonal variation of nitrification performance in secondary treatment as well as change in temperature caused seasonal variation in residual chlorine profile along the river.

Chlorine Compounds↗
PubMed2002

Onsite wastewater differential treatment system: modeling approach.

In this paper, the Onsite Wastewater Differential Treatment System (OWDTS), a new approach for improving the traditional onsite wastewater treatment systems (OWTS), is proposed based on differential management and treatment of household wastewater effluents. Three fractions of household wastewater have been differentiated, reduced-volume blackwater, higher-load graywater and lower-load graywater. Based on this differentiation, different treatment processes required for each fraction are discussed. The procedure adopted for treatment of toilet wastes (reduced-volume blackwater) is shown. In the case of graywater, a sketch of treatment processes is provided. The OWDTS seems to be a new approach with higher potential for improvement of traditional OWTS, dry ecological sanitation, recycling of resources (toilet wastes and water), conservation of water resources, etc. Aerobic biodegradation of toilet wastes by using sawdust as a matrix is an essential treatment process of the OWDTS. Membrane technology seems to be the most effective process to treat higher-load gray water. Natural biodegradation of lower-load gray water by soil bacteria needs to be deeply studied.

Biodegradation, Environmental↗
PubMed2001

Frequent mutations of Fas gene in thyroid lymphoma.

Fas (Apo-1/CD95) is a cell-surface receptor involved in cell death signaling through binding of Fas ligand. Mutation of the Fas gene results in accumulation of lymphoid cells and thus might contribute to lymphomagenesis. Thyroid lymphoma (TL) is supposed to arise from active lymphoid cells formed in the preceding autoimmune chronic lymphocytic thyroiditis (CLTH). We examined the open reading frame of Fas cDNA in 11 cases of CLTH and 26 cases of TL. These patients were admitted to the hospital with varying degrees of goiter. All of the CLTH patients were female, with median age of 65 years, and all but five cases of TL were female, with median age of 61 years. Mutations of the Fas gene were detected in 3 (27.3%) of 11 cases of CLTH and 17 (65.4%) of 26 of TL. The Fas mutations comprised 18 frameshift, 3 missense, and 1 nonsense mutation. Frameshift mutations were caused by insertion of 1 bp (A) at nucleotide 1095 in 10 cases and by lack of exon 8 in 8 cases. The insertion of 1 bp (A) at nucleotide 1095 has never been reported in other kinds of malignancies. Thus, this might be unique in TL and CLTH and might be mutational hotspots in these diseases. All mutations occurred in the cytoplasmic region (death domain) known to be involved in the apoptotic signal transduction and thus could be loss-of-function mutations. These findings suggested that accumulation of lymphoid cells in CLTH with Fas mutation provides a basis for development of TL.

Aged↗
PubMed2001

Fas gene mutations in prostatic intraepithelial neoplasia and concurrent carcinoma: analysis of laser capture microdissected specimens.

Fas (Apo-1/CD95) is a cell-surface receptor involved in cell death signaling through binding of Fas ligand. Mutations of the Fas gene might be involved in proliferative diseases of the prostate by prolongation of programmed cell death of prostatic epithelial cells. Using the laser capture microdissection method, Fas gene mutations were examined on genomic DNA extracted from lesions with high-grade prostatic intraepithelial neoplasia (HGPIN), a possible precursor of prostatic cancer (PCA), and from PCA. A total of 193 lesions, 111 with HGPIN, 55 with PCA, and 27 benign glands, were microdissected from 27 patients with PCA. Polymerase chain reaction-amplified products were directly sequenced. Loss of heterozygosity (LOH) was examined at four sites of known polymorphisms. Fas gene mutations were detected in HGPIN: 4 of 27 (14.8%) cases or 4 of 111 (3.6%) lesions. All were point mutations: three missense and one nonsense in the death domain. Benign proliferative glands adjoining HGPIN and/or PCA, and PCA never showed mutations. LOH was found in 31.3% of PCA and 25% of HGPIN lesions, but was never found in benign glands. Exclusive occurrence of Fas mutations in HGPIN might underlie the development of these lesions. Occasional findings of LOH in HGPIN and PCA suggested that genetic instability might occur during the early phase of prostatic carcinogenesis.

Alleles↗
PubMed2001

DNA sequence of immunoglobulin heavy chain variable region gene in thyroid lymphoma.

Patho-epidemiological studies have shown that thyroid lymphoma (TL) develops in thyroid affected by chronic lymphocytic thyroiditis (CLTH). CLTH is categorized as an organ-specific autoimmune disease, in which activated B-lymphocytes secrete a number of autoantibodies. Because antigenic stimulation might be involved in the pathogenesis of TL, the variable region in heavy chain (V(H)) genes was characterized in 13 cases with TL and 3 with CLTH. Clonal rearrangement of the V(H) gene was found in 11 cases of TL, and cloning study with sequencing of complimentary determining region (CDR) 3 revealed the presence of a major clone in 4. Three of the 4 cases used V(H) 3 gene, with the homologous germline gene of V3-30 in two cases and VH26 in one case. A biased usage of V(H) 3 and V(H) 4 genes with the homologous germline gene of VH26 in V(H) 3 gene was reported previously in cases with CLTH. A high level of somatic mutation (1-21%, average 12%) with non-random distribution of replacement and silent mutations was accumulated in all cases. The frequency of the occurrence of minor clones ranged from 29-44% per case, indicating the presence of on-going mutation. DNA sequencing of immunoglobulin V(H) gene suggests that TL develops among activated lymphoid cells in CLTH at the germinal center stage under antigen selection.

ATP-Binding Cassette Transporters↗
PubMed2001

Primary pancreatic lymphoma: clinicopathological analysis of 19 cases from Japan and review of the literature.

Primary pancreatic lymphoma (PL) is an extremely rare disease, and large-scale studies are rarely performed even in Western countries, in which all cases of PL reported to date were of the B-cell type. Little information regarding PL is available in Japan. Nineteen cases of PL were collected through a nationwide study in Japan, and paraffin-embedded specimens were processed for staining with hematoxylin and eosin and by immunohistochemical procedures. Clinicopathological findings were reviewed and compared with those reported in Western countries. The patient population consisted of 13 men and 6 women, ranging in age from 46 to 84 (average 62) years. Abdominal pain was the most common presenting symptom. Tumors were located in the pancreatic head (12 cases), tail (4 cases) and body (2 cases), and ranged in size from 4 to 17 cm. Clinical stage was I(E) in 9 cases and II(E) in 10. Radical resection was performed in 10 cases and bypass operation in 1, followed by chemotherapy in 8. Immunophenotypically, 15 cases were B-cell and 4 were T-cell lymphomas. Seventy-three percent of B-cell tumors were diffuse large B-cell lymphomas. The 1-year actuarial survival rate for B-cell lymphomas (51.9%) was better than that of T-cell lymphomas (0%). However, in Japan the incidence of T-cell PLs was higher, and, partly as a consequence of this, prognosis was poorer than in Western countries.

Adult↗
PubMed2001

[Resistance to Fas-mediated apoptosis in human papillomavirus type 16-immortalized human laryngeal epithelial cells after tumorigenesis].

Apoptosis plays an important role in such biological processes as multistep carcinogenesis. Human papillomavirus type 16(HPV16)-immortalized human epithelial cell lines are, for the most part, nontumorigenic in nude mice and useful for studying mechanisms involved in multistep carcinogenesis. We previously reported that HPV16-immortalized human laryngeal epithelial cell line HLEC16 formed tumors after treatment with 4-(methyl-nitrosamine)-1-(3-pyridyl)-1-butanone, and derived one tumorigenic cell line, HLEC16T. We compared sensitivity to Fas receptor-mediated apoptosis of nontumorigenic HLEC16 and tumorigenic HLEC16T. HLEC16 and HLEC16T expressed Fas protein (Fas) but not Fas-ligand (FasL) mRNA. We applied an anti-Fas monoclonal, antibody, CH11, to HLEC16 and HLEC16T, and monitored cell death. HLEC16T was found to be significantly less sensitive to CH11-mediated cell death that HLEC16. Western blot analysis showed no significant difference in levels of apoptosis-inducing protein, Bax, between HLEC16 and HLEC16T. Levels of apoptosis-inhibiting proteins Bcl-2 and Bcl-XL increased in HLEC16T. These results suggest that the inhibition of Fas-mediated apoptosis through apoptosis-inhibiting protein overexpression may promote tumorigenicity in HLEC16T.

Animals↗
PubMed2001

Reuse of heat energy in wastewater: implementation examples in Japan.

Sewage and treated water can be a heat source in urban area due to large heat capacity, thus recovery and reuse of its energy is one of the most desirable plans for the sewerage system. In this paper, characteristics of heat energy in wastewater, reuse plans, and some experiences in Japan are presented. Full-scale reuse projects for heating and cooling in the Tokyo Metropolitan Districts and project for melting snow in Sapporo City are discussed. The key factors found in experience of Tokyo were setting the heat pumps near the demand points and the technical developments of equipment to prevent system from clogging, corrosion, and decrease in the heat transfer efficiency. It was also found through the project for melting snow in Sapporo that the key factor in public acceptance was the multi-purpose use of the sewerage system both for melting snow in winter and retaining rain water in summer.

Air Conditioning↗
PubMed2001

[Hypermethylation of DAP-kinase gene CpG Island in malignant lymphoma with B-cell phenotype].

Death-associated protein-kinase(DAP-Kinase) is a pro-apoptotic serine/threonine kinase with a death domain, which is involved in apoptosis induced by interferon-gamma, tumor necrosis factor-alpha, and Fas ligand. Epigenetic down-regulation of DAP-Kinase gene expression by hypermethylation of its promoter region was reported in certain kinds of malignancies. Previous patho-epidemiological studies indicated that thyroid lymphoma(TL) evolves among active lymphoid cells in chronic lymphocytic thyroiditis(CLTH). With the use of methylation specific polymerase chain reaction, methylation status of DAP-Kinase CpG island was examined in thyroid lesions of 19 cases with TL and 9 with CLTH. Frequency of methylation was higher in TL cases(16 of 19, 84.2%) than in CLTH cases(2 of 9, 22.2%) (p < 0.01). DNA extracted from peripheral blood leukocytes from TL and CLTH cases never showed methylation, indicating that the methylation occurred somatically in lesional lymphocytes in the thyroid. We also examined the methylation status of DAP-kinase gene in 16 cases of T-cell malignancies including eight adult T-cell leukemia/lymphoma and 24 NK/T-cell, 34 B-cell, and two immunophenotypically undetermined lymphomas. Frequency of methylation was higher in B-cell(27 of 34, 79.4%) than in T-cell malignancies(eight of 16, 50%) (p < 0.05). Fifteen of 24(62.5%) NK/T-cell lymphomas showed DNA methylation. Hematopoietic cell lines with a methylated gene were resistant to apoptosis. Treatment of the cells with a demethylating agent restored apoptotic cell death in one B-cell lymphoma cell line with DNA methylation. Our results suggested that suppression of DAP-Kinase expression by DNA methylation might play a role in the development of B-cell malignancies.

Animals↗
PubMed2000

Nuclear expression of the p16CDKN2 gene product during senescence of human pharyngeal epithelial cells.

OBJECTIVE: It has been proposed that a gene mapping to human chromosome 9p21 plays a critical role in cellular senescence. CDKN2 is a tumor suppressor gene on chromosome 9p21. It encodes a nuclear protein, p16, which inhibits the D-type cyclin/cyclin-dependent kinase complexes that phosphorylate the retinoblastoma protein, thus blocking cell cycle progression through G1. The purpose of this study was to determine whether nuclear p16 expression is altered during the senescence of human pharyngeal epithelial cells (HPECs) m vitro. METHODS: An immunocytochemical study was performed to examine a panel of cultured HPECs with a finite lifespan for the nuclear p16 expression. All HPEC cultures were also subjected to a histochemical assay that identifies senescent cells by their positive beta-galactosidase activity. RESULTS: Nuclear p16 was undetectable when HPECs were initially cultured in serum-free low-calcium medium. However, nuclear p16 was clearly detected when the cultured HPECs exhibited beta-galactosidase activity in the same medium. CONCLUSION: These results suggest that immunocytochemically detectable amounts of nuclear p16 are associated with senescence of HPECs in vitro.

Calcium↗
PubMed2000

Expression of interleukin-7 and its receptor in thyroid lymphoma.

Patho-epidemiological studies have shown that thyroid lymphomas (TL) develop in thyroids affected by chronic lymphocytic thyroiditis (CLTH). Cytokines produced in CLTH might play a pivotal role for lymphomagenesis, because previous reports indicate an important role of cytokines in lymphomagenesis. We examined the expression of interleukin-7 (IL-7), a pleiotropic cytokine that acts mainly on cells of the hematolymphoid system, and IL-7 receptor (IL-7R) in both TL and CLTH by RT-PCR. IL-7-specific transcripts were detected more frequently in TL than in CLTH lesions (p < 0.01). IL-7 expression was higher in TL than in CLTH. IL-7R and the common gamma chain were expressed in all but one TL and in all CLTH lesions, in similar levels. We established the sensitive in situ hybridization (ISH) method for detection of IL-7. ISH for IL-7 revealed cytoplasmic signals among cells in the germinal center and mantle zone of lymphoid follicles and interfollicular areas in the TL and CLTH lesions. In the lymphomatous areas of TL, similar numbers of scattered large and small lymphoid cells expressing IL-7 were found. The number of IL-7-expressing cells counted in 10 fields in TL (119.4 +/- 10.6 cells) was significantly higher than found in CLTH lesions (43.1 +/- 4.6) (p < 0.001). These findings suggest a pathogenetic role for IL-7 in the development of TL. ISH showed that the germinal center cells, interfollicular cells, and lymphoma cells expressed IL-7R, but mantle zone cells did not. Because lymphoid cells in lymphoid follicles and the interfollicular area formed in CLTH expressed IL-7, TL cells might proliferate via their own IL-7 and IL-7R, and via IL-7 from reactive lymphoid cells.

Aged↗
PubMed2000

Role of hypermethylation of DAP-kinase CpG island in the development of thyroid lymphoma.

Death-associated protein-kinase (DAP-Kinase) is a serine/threonine kinase with a death domain that is involved in apoptosis induced by interferon-gamma, TNF-alpha, and Fas ligand. Epigenetic down-regulation of DAP-Kinase gene expression by hypermethylation of its promoter region was reported in B-cell malignancies. Previous pathoepidemiologic studies indicated that thyroid lymphoma (TL) evolves among active lymphoid cells in chronic lymphocytic thyroiditis (CLTH). With use of methylation-specific polymerase chain reaction, the methylation status of DAP-Kinase CpG island was examined in thyroid lesions of 19 cases with TL and 9 with CLTH. The frequency of methylation was higher in TL cases (16 of 19, 84.2%) than in CLTH cases (2 of 9, 22.2%) (p < 0.01). DNA extracted from peripheral blood leukocytes from TL and CLTH cases never showed methylation, indicating that the methylation occurred somatically in the lesional lymphocytes in thyroid. These findings suggested that methylation of the DAP-Kinase promoter region might be involved in the development of TL from CLTH.

Adult↗