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R Kitagawa

Publications and source records attributed to R Kitagawa.

At least 19 recordsLinked to original sources
PubMed2006

Neuronal specificity of alpha-synuclein toxicity and effect of Parkin co-expression in primates.

Recombinant adeno-associated viral (rAAV) vector-mediated overexpression of alpha-synuclein (alphaSyn) protein has been shown to cause neurodegeneration of the nigrostriatal dopaminergic pathway in rodents and primates. Using serotype-2 rAAV vectors, we recently reported the protective effect of Parkin on alphaSyn-induced nigral dopaminergic neurodegeneration in a rat model. Here we investigated the neuronal specificity of alphaSyn toxicity and the effect of Parkin co-expression in a primate model. We used another serotype (type-1) of AAV vector that was confirmed to deliver genes of interest anterogradely and retrogradely to neurons in rats. The serotype-1 rAAV (rAAV1) carrying alphaSyn cDNA (rAAV1-alphaSyn), and a cocktail of rAAV1-alphaSyn and rAAV1 carrying parkin cDNA (rAAV1-parkin) were unilaterally injected into the striatum of macaque monkeys, resulting in protein expression in striatonigral GABAergic and nigrostriatal dopaminergic neurons. Injection of rAAV1-alphaSyn alone decreased tyrosine hydroxylase immunoreactivity in the striatum compared with the contralateral side injected with a cocktail of rAAV1-alphaSyn and rAAV1-parkin. Immunostaining of striatonigral GABAergic neurons was similar on both sides. Overexpression of Parkin in GABAergic neurons was associated with less accumulation of alphaSyn protein and/or phosphorylation at Ser129 residue. Our results suggest that the toxicity of accumulated alphaSyn is not induced in non-dopaminergic neurons and that the alphaSyn-ablating effect of Parkin is exerted in virtually all neurons in primates.

Animals↗
PubMed2005

Phase II trial of docetaxel in advanced or metastatic endometrial cancer: a Japanese Cooperative Study.

The purpose of this study was to determine whether docetaxel has antitumour activity in patients with advanced or recurrent endometrial carcinoma. Chemotherapy-naïve or previously treated patients (one regimen) with histopathologically documented endometrial carcinoma and Eastern Cooperative Oncology Group performance status </=2 entered the study. Docetaxel 70 mg m(-2) was administered intravenously on day 1 of a 3-week cycle up to a maximum of six cycles. If patients responded well to docetaxel, additional cycles were administered until progressive disease or unacceptable toxicity occurred. Of 33 patients with a median age of 59 years (range, 39-74 years) who entered the study, 14 patients (42%) had received one prior chemotherapy regimen. In all, 32 patients were evaluable for efficacy, yielding an overall response rate of 31% (95% confidence interval, 16.1-50.0%); complete response and partial response (PR) were 3 and 28%, respectively. Of 13 pretreated patients, three (23%) had a PR. The median duration of response was 1.8 months. The median time to progression was 3.9 months. The predominant toxicity was grade 3-4 neutropenia, occurring in 94% of the patients, although febrile neutropenia arose in 9% of the patients. Oedema was mild and infrequent. Docetaxel has antitumour activity in patients with advanced or recurrent endometrial carcinoma, including those previously treated with chemotherapy; however, the effect was transient and accompanied by pronounced neutropenia in most patients.

Adenocarcinoma↗
PubMed2005

Inhibitory effect of hexamethylene bisacetamide on replication of human cytomegalovirus.

The effect of hexamethylane bisacetamide (HMBA), a hybrid polar compound, on gene expression and replication of human cytomegalovirus (HCMV) was studied. When HCMV-infected human thyroid papillary carcinoma (TPC-1) and human embryonic lung (HEL) fibroblast cells were maintained with medium containing 2.5 and 5 mM HMBA for 10 days, there was a greater than 2- to 3-log reduction in virus yield compared to that in untreated cells. Infection of TPC-1 cells with HCMV resulted in an establishment of persistent infection and the cells continuously produced virus with titer of over 10(5) PFU/ml, whereas HMBA prevented the infected cells from entering into the persistent infection. Moreover, treatment of the persistently infected cultures with HMBA reduced production of infectious HCMV more efficiently than did ganciclovir, and eventually ceased HCMV production. Western blotting analysis revealed that HMBA blocks accumulation of the immediate early 2 (IE2) protein in TPC-1 cells and delays synthesis of this protein in HEL cells, but has little effect on the level of the IE1 protein during the early times after infection. Synthesis of the viral early and late proteins in both cells was also substantially blocked by HMBA. The results indicate that the inhibition or the delay of the critical IE2 protein synthesis in the presence of HMBA would actually be a process that fails to proceed beyond the IE stages in HCMV replication cycle.

Acetamides↗
PubMed2005

The ATM-dependent DNA damage signaling pathway.

Many of the insights that we have gained into the mechanisms involved in cellular DNA damage response pathways have come from studies of human cancer susceptibility syndromes that are altered in DNA damage responses. ATM, the gene mutated in the disorder, ataxia-telangiectasia, is a protein kinase that is a central mediator of responses to DNA double-strand breaks in cells. Recent studies have elucidated the mechanism by which DNA damage activates the ATM kinase and initiates these critical cellular signaling pathways. The SMC1 protein appears to be a particularly important target of the ATM kinase, playing critical roles in controlling DNA replication forks and DNA repair after the damage. A major role for the NBS1 and BRCA1 proteins appears to be in the recruitment of an activated ATM kinase molecule to the sites of DNA breaks so that ATM can phosphorylate SMC1. Generation of mice and cells that are unable to phosphorylate SMC1 demonstrated the importance of SMC1 phosphorylation in the DNA-damage-induced S-phase checkpoint, in determining rates of repair of chromosomal breaks, and in determining cell survival after DNA damage. Focusing on ATM and SMC1, the molecular controls of these pathways is discussed.

Animals↗
PubMed2001

Molecular cloning of human and mouse DJ-1 genes and identification of Sp1-dependent activation of the human DJ-1 promoter.

DJ-1 has been identified as a novel oncogene that transforms mouse NIH3T3 cells in cooperation with activated ras. Subsequently, two other groups have identified SP22 or CAP-1, rat homologs of human DJ-1, as a sperm protein targeted by some toxicants leading to male infertility, and another group has also reported that RS, the same as human DJ-1, is a component of an RNA-binding protein complex. To characterize the expression or functional importance of DJ-1, the genomic DNAs of both human and mouse DJ-1 were cloned and characterized. Both genomic DNAs comprise 7 exons spanning about 16-24 kb, in which 2-6 exons encode the DJ-1 protein. The human DJ-1 gene was mapped at chromosome 1p36.2-p36.3, a region that has been shown to be a hot spot of chromosome abnormalities in several tumor cells. To analyze the promoter of the human DJ-1 gene, a series of deletion constructs of the region upstream of exon 2 were linked to the luciferase gene, and their luciferase activities were measured in human HeLa cells. Of the many putative transcription regulatory sequences, the Sp1 site present at -100 from the transcription initiation site contributed to the major promoter activity, and Sp1 was identified as a protein binding to this site by a mobility shift assay using HeLa nuclear extract.

Amino Acid Sequence↗
PubMed2001

Anomalous DnaA protein binding to the regulatory region of the Escherichia coli aldA gene.

A binding site for DnaA protein was identified in the regulatory region of the aldA gene of Escherichia coli. Specific binding was demonstrated by in vitro assays including filter binding as well as mobility shift in a polyacrylamide gel of the DnaA-DNA complex. In cells growing in minimal medium containing glucose, expression of ss-galactosidase activity from an aldA-lacZ fusion gene was suppressed by oversupply of DnaA protein and was enhanced by reducing the free DnaA level. These results suggest that DnaA protein negatively regulates expression of the aldA gene under these conditions. Despite fairly strong binding, the bound DNA fragment had no consensus 9 bp DnaA binding sequence (DnaA box), and anomalous binding to an AT-rich sequence located close to the transcription start site was revealed by a footprinting experiment.

Aldehyde Dehydrogenase↗
PubMed2000

EMB-30: an APC4 homologue required for metaphase-to-anaphase transitions during meiosis and mitosis in Caenorhabditis elegans.

Here we show that emb-30 is required for metaphase-to-anaphase transitions during meiosis and mitosis in Caenorhabditis elegans. Germline-specific emb-30 mutant alleles block the meiotic divisions. Mutant oocytes, fertilized by wild-type sperm, set up a meiotic spindle but do not progress to anaphase I. As a result, polar bodies are not produced, pronuclei fail to form, and cytokinesis does not occur. Severe-reduction-of-function emb-30 alleles (class I alleles) result in zygotic sterility and lead to germline and somatic defects that are consistent with an essential role in promoting the metaphase-to-anaphase transition during mitosis. Analysis of the vulval cell lineages in these emb-30(class I) mutant animals suggests that mitosis is lengthened and eventually arrested when maternally contributed emb-30 becomes limiting. By further reducing maternal emb-30 function contributed to class I mutant animals, we show that emb-30 is required for the metaphase-to-anaphase transition in many, if not all, cells. Metaphase arrest in emb-30 mutants is not due to activation of the spindle assembly checkpoint but rather reflects an essential emb-30 requirement for M-phase progression. A reduction in emb-30 activity can suppress the lethality and sterility caused by a null mutation in mdf-1, a component of the spindle assembly checkpoint machinery. This result suggests that delaying anaphase onset can bypass the spindle checkpoint requirement for normal development. Positional cloning established that emb-30 encodes the likely C. elegans orthologue of APC4/Lid1, a component of the anaphase-promoting complex/cyclosome, required for the metaphase-to-anaphase transition. Thus, the anaphase-promoting complex/cyclosome is likely to be required for all metaphase-to-anaphase transitions in a multicellular organism.

Alleles↗
PubMed1999

Components of the spindle-assembly checkpoint are essential in Caenorhabditis elegans.

The spindle-assembly checkpoint ensures that, during mitosis and meiosis, chromosomes do not segregate until they are properly attached to the microtubules of the spindle. Here we show that mdf-1 and mdf-2 are components of the spindle-assembly checkpoint in Caenorhabditis elegans, and are essential for the long-term survival and fertility of this organism. Loss of function of either of these genes leads to the accumulation of a variety of defects, including chromosome abnormalities, X-chromosome non-disjunction or loss, problems in gonad development, and embryonic lethality. Antibodies that recognize the MDF-2 protein localize to nuclei of the cleaving embryo in a cell-cycle-dependent manner. mdf-1, a gene encoding a product that interacts with MDF-2, is required for cell-cycle arrest and proper chromosome segregation in premeiotic germ cells treated with nocodazole, a microtubule-depolymerizing agent. In the absence of mdf gene products, errors in chromosome segregation arise and accumulate, ultimately leading to genetic lethality.

Animals↗
PubMed1998

Negative control of replication initiation by a novel chromosomal locus exhibiting exceptional affinity for Escherichia coli DnaA protein.

Replication of the Escherichia coli chromosome is initiated at a unique site, oriC. Concurrent initiation occurs at all oriC sites present in a cell once, and only once, per cell cycle. A mechanism to ensure cyclic initiation events was found operating through the chromosomal site, datA, a 1-kb segment located at 94.7 min on the genetic map that titrates exceptionally large amounts of the bacterial initiator protein, DnaA. A strain lacking datA grew normally but exhibited an asynchronous initiation phenotype as a result of extra initiation events. This mutant phenotype was suppressed by DnaA-titrating plasmids. Furthermore, mutations in a 9-bp DnaA-binding sequence (the DnaA box) in datA were enough to induce the mutant phenotype. Thus, datA is a novel chromosomal element that appears to adjust a balance between free and bound DnaA for a single initiation event at a fixed time in the bacterial cell cycle. Titration of DnaA to newly duplicated datA during oriC sequestration, which is mediated by hemimethylated GATC sequences in oriC and the SeqA protein, would contribute to prevention of reinitiations when oriC is desequestered.

Bacterial Outer Membrane Proteins↗
PubMed1997

Immunohistochemical study of tumor-infiltrating lymphocytes before and after intravesical bacillus Calmette-Guérin treatment for superficial bladder cancer.

BACKGROUND: This study investigated changes in the phenotypic characteristics of tumor-infiltrating lymphocytes during intravesical bacillus Calmette-Guérin (BCG) treatment using an immunohistochemical technique. METHODS: A total of 16 patients with superficial bladder cancer underwent intravesical BCG treatment for therapeutic purposes. Tissue specimens were obtained from these patients before and after BCG treatment by cold cup biopsies. RESULTS: The numbers of CD3+ cells, CD4+ cells, CD8+ cells, and CD19+ cells significantly increased after treatment compared with numbers before treatment (P < 0.01). Although gamma/delta T cells were not observed before treatment, they appeared after treatment in 6 patients. In all these patients, the tumors disappeared or their size was reduced by more than 50%, and none of the tumors recurred. The induction of CD25+ cells after treatment was seen in 11 of the 16 patients. CONCLUSION: gamma/delta T cells may play an important role in the immune response of the host to the tumor in intravesical BCG treatment (although this correlation was statistically insignificant.

Adjuvants, Immunologic↗
PubMed1997

Distal ureteral atresia associated with crossed renal ectopia with fusion: recovery of renal function after release of a 10-year ureteral obstruction.

We report on a 10-year-old boy with distal ureteral atresia associated with crossed renal ectopia with fusion. He was admitted with a high fever associated with a urinary tract infection. The diagnosis was established by antegrade and retrograde pyelography. The upper hydronephrotic portion of the kidney, obstructed for 10 years, recovered its function after nephrostomy placement. To our knowledge, this is the first patient whose renal function has recovered despite an ureteral obstruction of 10-years' duration. Therefore, we recommend a transient nephrostomy placement even for far advanced pediatric hydronephrosis, to test for the possibility of functional recovery.

Abnormalities, Multiple↗
PubMed1996

Orderly disposition of heterogeneous small subunits in D-ribulose-1,5-bisphosphate carboxylase/oxygenase from spinach.

We determined the crystal structure of spinach ribulose-1, 5-bisphosphate carboxylase/oxygenase (Rubisco) by x-ray diffraction at 1.8-A resolution and found that the enzyme contained two kinds of S, SI and SII, present in equal number and disposed in an orderly way within the Rubisco holoenzyme. The electron density maps suggested that leucine was at residue 56 in SI, although histidine was at that position in SII. There were other residue differences. Thus, spinach Rubisco has a L8SI4SII4 subunit structure. The orderly disposition of the heterogeneous small subunits in the Rubisco holoenzyme provides accounts of a multigene family of S in plants.

Crystallography, X-Ray↗
PubMed1996

A novel DnaA protein-binding site at 94.7 min on the Escherichia coli chromosome.

There is a DNA sequence which has unusually high affinity for the DnaA protein of Escherichia coli between the glyV and amiB-mutL operons at 94.7 min on the genetic map. Affinity of DnaA protein for DNA was measured in vivo as the activity of beta-galactosidase produced from the lacZ gene on a plasmid fused to the 5'-terminal portion of the mioC gene, which is under the control of the DnaA protein. The chromosomal DNA segment between the two operons, carried on a compatible plasmid, derepressed the beta-galactosidase activity by titrating DnaA protein. Derepression occurred on the chromosomal dnaA gene as well, since it is autoregulated. Hence, as measured by immunoassays, one plasmid molecule carrying the DnaA-binding region titrated 370 dnaA molecules, which is a value eightfold higher than that for a plasmid containing the oriC region. We estimate that about 60% of the total cellular DnaA molecules are bound to this site. Four DnaA-binding sequences (DnaA boxes) and a DnaA-regulated promoter directing transcription of two small genes were present within a 250 bp stretch in this region but additional long DNA regions, including the fifth DnaA box located about 650 bp downstream, were required for maximum binding. A role for the DnaA-binding site in controlling DnaA-protein concentration in the cell cycle is discussed.

Bacterial Proteins↗
PubMed1996

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1994). I. Susceptibility distribution].

The frequencies of isolation and susceptibilities to antimicrobial agents were investigated on 567 bacterial strains isolated from patients with urinary tract infections in 10 hospitals during the period of June 1994 to May 1995. Of the above total bacterial isolates, Gram-positive bacteria accounted for 26.8% and a majority of them were Enterococcus faecalis. Gram-negative bacteria accounted for 73.2% and most of them were Escherichia coli. 1. Enterococcus faecalis. Ampicillin (ABPC) and imipenem (IPM) showed the highest activities against E. faecalis isolated from patients with urinary tract infections. The MIC90s of them were 1 microgram/ml. Vancomycin (VCM) was also active with the MIC90 of 2 micrograms/ml. Piperacillin (PIPC) and biapenem (BIPM) were also active with the MIC90s of 4 micrograms/ml and 8 micrograms/ml, respectively. The others were not so active with the MIC90s of 16 micrograms/ml or above. 2. Staphylococcus aureus including MRSA. VCM showed the highest activities against S. aureus isolated from patients with urinary tract infections. Its MIC90 was 1 microgram/ml against both S. aureus and MRSA. Arbekacin (ABK) was also active with the MIC90 of 2 micrograms/ml. The others except minocycline (MINO) were not so active with the MIC90s of 64 micrograms/ml or above. 3. Staphylococcus epidermidis. MINO showed the strongest activity against S. epidermidis isolated from patients with urinary tract infections. Its MIC90 was 0.25 microgram/ml. ABK was also active with the MIC90 of 1 microgram/ml. Cephems were active with the MIC90s of 2 approximately 16 micrograms/ml, but penicillins and quinolones were not so active with the MIC90s and 64 approximately 128 micrograms/ml. 4. Citrobacter freundii. Gentamicin (GM) showed the highest activities against C. freundii isolated from patients with urinary tract infections. Its MIC90 was 1 microgram/ml. IPM was also active with the MIC90 of 2 micrograms/ml. Cefpirome (CPR) and cefozopran (CZOP) were also active with the MIC90s of 4 micrograms/ml and 8 micrograms/ml. The others were not so active with the MIC90s of 32 micrograms/ml or above. 5. Enterobacter cloacae. IPM showed the highest activities against E. cloacae. Its MIC90 was 0.5 microgram/ml. GM and amikacin (AMK), ciprofloxacin (CPFX) and tosulfloxacin (TFLX) were also active with the MIC90s of 4 micrograms/ml. Penicillins and cephems except latamoxef (LMOX), cefmenoxime (CMX), CPR and CZOP showed lower activities with the MIC90s of 256 micrograms/ml or above. 6. Escherichia coli. Most of antimicrobial agents were active against E. coli. CPR, CZOP, IPM, carumonam (CRMN), CPFX and TFLX showed the highest activities against E. coli. The MIC90s of them were 0.125 microgram/ml or below. Cefotiam (CTM), flomoxef (FMOX) CMX, ceftazidime (CAZ), and LMOX were also active with the MIC90s of 0.25 microgram/ml. Penicillins were not so active with the MIC90s of 128 micrograms/ml or above. 7. Klebsiella pneumoniae. CRMN showed the highest activities against K. pneumoniae. Its MIC90 was < or = 0.125 microgram/ml. CZOP was also active with the MIC90 of 0.25 microgram/ml. Penicillins were not so active with the MIC90s of 128 micrograms/ml or above. 8. Proteus mirabilis. P. mirabilis was susceptible to a majority of drugs. CMX, CAZ, LMOX, CRP, cefpodoxime (CPDX), CRMN, CPFX and TFLX showed the highest activities against P. mirabilis isolated from patients with urinary tract infections. The MIC90s of them were 0.125 microgram/ml or below. MINO was not so active with the MIC90 of 128 micrograms/ml. 9. Pseudomonas aeruginosa. Most of the agents were not so active against P. aeruginosa. IPM showed MIC90 of 8 micrograms/ml. The others were not so active with the MIC90s of 16 micrograms/ml or above. CPFX showed MIC50 of 0.5 microgram/ml.

Anti-Bacterial Agents↗
PubMed1996

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1994). II. Background of patients].

Clinical background was investigated on 628 bacterial strains isolated from patients with urinary tract infections (UTIs) in 10 hospitals during period from June, 1994 to May, 1995. 1. Distributions of sex, age and urinary tract infections Among over sixties males, the majority was taken by complicated urinary tract infections. Among females, the uncomplicated urinary tract infections was most frequent without a relation of age. As for over 40 females, the increase of complicated UTI was admitted. 2. Distribution of sex, age and pathogens isolated from UTIs In uncomplicated UTIs, Escherichia coli was most frequently isolated without a relation of age, and next Enterococcus faecalis and CNS. In complicated UTIs without indwelling catheter, E. coli, Pseudomonas aeruginosa and E. faecalis were isolated the most frequent. In complicated UTIs with indwelling catheter, P. aeruginosa was most frequently isolated, and next E. faecalis and Staphylococcus aureus. 3. Administration of antimicrobial agents and pathogens isolated from UTIs In uncomplicated UTIs, pathogens, after administration of antibiotics, isolated from patients have obviously decreased from 216 to 32 isolates. And also, pathogens of complicated UTIs without indwelling catheter, have decreased from 127 to 50 isolates. However, in complicated UTIs with indwelling catheter, pathogens after or before administration of antibiotics, were not revealed an obvious change. 4. Pathogens and UTIs with or without factor and operation In uncomplicated UTIs with or without factor and operation, E. coli was mainly detected. In complicated UTIs without indwelling catheter and with factor and operation E. faecalis was mainly detected, and next E. coli, S. aureus and P. aeruginosa. Without factor and operation, E. coli was mainly detected. In complicated UTIs with indwelling catheter and with factor and operation, P. aeruginosa, E. faecalis and S. aureus were mainly detected at 23.5%, 15.0%, 15.0%, respectively. Without factor and operation, Proteus spp. 22%, and next E. faecalis and P. aeruginosa 10% and 12%, were detected, respectively. The distribution of pathogens, in the case of Proteus spp. and P. aeruginosa has been obviously varied by the influence of factor and operation.

Adolescent↗
PubMed1996

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1994). III. Secular changes in susceptibility].

Susceptibilities of Enterococcus faecalis, Staphylococcus aureus, Citrobacter spp., Enterobacter spp., Escherichia coli, Klebsiella spp., Proteus mirabilis, Pseudomonas aeruginosa and Serratia spp. isolated from patients with urinary tract infections (UTIs) in 10 hospitals during June 1994 to May 1995 to various antimicrobial agents were compared with those in the same period of previous years according to a classification, uncomplicated UTIs, complicated UTIs without indwelling catheter, and complicated UTIs with indwelling catheter. No remarkable changes were found in susceptibilities of Citrobacter spp., Enterobacter spp. and Serratia spp. The susceptibilities of E. faecalis to amikacin and quinolones were better than those in 1993. As for S. aureus, susceptible strains to all drugs increased in uncomplicated UTIs. Against E. coli in 1993, the antimicrobial activities of piperacillin, cefotiam and aminoglycosides have decreased, however, in 1994, these activities have turned to the better state. As for Klebsiella spp. susceptible strains to ABPC decreased. The susceptibilities of P. mirabilis to all drugs except minocycline were good. Against P. aeruginosa in 1993, the activities of aminoglycosides have decreased, but, in 1994, these activities have turned to the better state. These data should be considered in clinical treatment of various urinary tract infections.

4-Quinolones↗
PubMed1994

Detection of interleukin-1 activity in human bladder cancer cell lines.

Detection of interleukin (IL)-1 activity was studied in two human bladder cancer cell lines, T24 and EJ1, and one rat bladder carcinoma cell line, 804G. Significantly high proliferation of mouse thymocytes in the assay of IL-1 activity was observed in the conditioned medium (CM) of T24 cells, indicating that the cells released IL-1-like activity. Enzyme-linked immunosorbent assay (ELISA) and Northern blot analysis showed the presence of both IL-1 alpha and IL-1 beta in the CM of T24 cells and expression of mRNAs of both cytokines in the cells. Interleukin-1 activity in EJ1 cells, which produced a little activity, was induced by E. coli lipopolysaccharide (LPS) while it was not induced in T24 by either LPS or other test substances. Conditioned medium of T24 increased proliferation of both T24 and EJ1 in cell-growth assay. Further investigation of the mode of action and role of cytokines, especially those from tumor cells themselves, is necessary in relation to BCG or photodynamic therapy.

Animals↗