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K Kinoshita

Publications and source records attributed to K Kinoshita.

At least 145 records · Page 8Linked to original sources
PubMed2001

Binding of the adenomatous polyposis coli protein to microtubules increases microtubule stability and is regulated by GSK3 beta phosphorylation.

Truncation mutations in the adenomatous polyposis coli protein (APC) are responsible for familial polyposis, a form of inherited colon cancer. In addition to its role in mediating beta-catenin degradation in the Wnt signaling pathway, APC plays a role in regulating microtubules. This was suggested by its localization to the end of dynamic microtubules in actively migrating areas of cells and by the apparent correlation between the dissociation of APC from polymerizing microtubules and their subsequent depolymerization [1, 2]. The microtubule binding domain is deleted in the transforming mutations of APC [3, 4]; however, the direct effect of APC protein on microtubules has never been examined. Here we show that binding of APC to microtubules increases microtubule stability in vivo and in vitro. Deleting the previously identified microtubule binding site from the C-terminal domain of APC does not eliminate its binding to microtubules but decreases the ability of APC to stabilize them significantly. The interaction of APC with microtubules is decreased by phosphorylation of APC by GSK3 beta. These data confirm the hypothesis that APC is involved in stabilizing microtubule ends. They also suggest that binding of APC to microtubules is mediated by at least two distinct sites and is regulated by phosphorylation.

Adenomatous Polyposis Coli Protein↗
PubMed2001

Study of B Decays to Charmonium States: B-->eta(c)K and B --> chi(c0)K.

In a sample of 9.66x10(6)B&Bmacr; pairs collected with the CLEO detector we make the first observation of B decays to an eta(c) and a kaon. We measure branching fractions B(B+-->eta(c)K+) = (0.69(+0.26)(-0.21)+/-0.08+/-0.20)x10(-3) and B(B degrees -->eta(c)K degrees ) = (1.09(+0.55)(-0.42)+/-0.12+/-0.31)x10(-3), where the first error is statistical, the second is systematic, and the third is from the eta(c) branching fraction uncertainty. From these we extract the eta(c) decay constant in the factorization approximation, f(eta(c)) = 335+/-75 MeV. We also search for B decays to a chi(c0) and a kaon. No evidence for a signal is found and we set 90% C.L. upper limits: B(B+-->chi(c0)K+)<4.8x10(-4) and B(B degrees -->chi(c0)K degrees )<5.0x10(-4).

Journal Article↗
PubMed2001

The membrane-bound but not the soluble form of human Fas ligand is responsible for its inflammatory activity.

The ectopic expression of Fas ligand (FasL/CD95L) in tissues or tumors induces neutrophil infiltration and the destruction of the tissues or the rejection of tumors. It has been suggested that the infiltrated neutrophils are responsible for the latter phenomena. FasL is synthesized as a type II transmembrane protein, and soluble FasL is produced by a proteolytic mechanism from the membrane-bound form. We previously demonstrated that uncleavable membrane-bound FasL of mice induces IL-1 beta release from inflammatory cells, and suggested that the IL-1 beta enhances neutrophil infiltration. However, recent papers reported that human soluble FasL is directly chemoattractive to neutrophils in vitro and proposed that the soluble form of FasL is responsible for its inflammatory activity. Therefore, in this report, we investigated which form is responsible for the inflammatory activities of human FasL. We produced tumor cell lines expressing one or both forms of human FasL. Cells expressing both forms or only the membrane-bound form of FasL induced neutrophil infiltration when transplanted into the peritoneal cavity of syngeneic mice, while cells expressing only the soluble form did not. Purified soluble FasL failed to induce neutrophil infiltration in vivo. IL-1 beta release from inflammatory peritoneal exudate and acceleration of tumor rejection were also mediated by membrane-bound but not soluble FasL. These results indicate that the membrane-bound form of FasL is primarily responsible for its inflammatory activity.

Animals↗
PubMed2001

The mechanism of the stabilization of the hexagonal II (HII) phase in phosphatidylethanolamine membranes in the presence of low concentrations of dimethyl sulfoxide.

Dimethyl sulfoxide (DMSO), a water-miscible organic solvent, has been used as a cryoprotectant for cells. It is known that DMSO stabilizes the HII phase of phosphatidylethanolamine (PE) membranes rather than the Lalpha phase, while most other water-miscible organic solvents such as acetone and ethanol destabilize the HII phase. To elucidate the mechanism for this stabilizing effect of DMSO on the HII phase, we have investigated its effects on the structures and physical properties of PE membranes. X-ray diffraction data indicated that dipalmitoleoylphosphatidylethanolamine (DPOPE) membranes in H2O at 20 degrees C were in the Lalpha phase and that an Lalpha to HII phase transition occurred at X=0.060 (mole fraction of DMSO) in water/DMSO mixtures. As the DMSO concentration increased, the basis vector length of the dioleoylphosphatidylethanolamine (DOPE)/ 16 wt% tetradecane membrane and also of the DPOPE/ 16 wt% tetradecane membrane in the HII phase decreased, suggesting that the spontaneous curvature of these membranes increased. We have also investigated the effects of DMSO on the physical properties of the PE membranes, and compared them with those of acetone. As the DMSO concentration increased, the excimer to monomer fluorescence intensities of pyrene-phosphatidylcholine in the PE membranes decreased, indicating that the membrane fluidity decreased, and also the generalized polarization value of the Laurdan fluorescent probe in the DPOPE membrane increased, indicating that the polarity of the membrane interface decreased. On the other hand, acetone had the opposite effects to DMSO. The interaction free energy between the membrane surface segments and solvent increased with an increase in DMSO concentration. It decreased the amount of solvent in the membrane interface, inducing an increase in the spontaneous curvature. This can reasonably explain the effects of DMSO on the phase stability and the physical properties of the membranes.

2-Naphthylamine↗
PubMed2001

Mortality and cancer incidence among a population previously exposed to environmental cadmium.

OBJECTIVES: This paper evaluates the associations of previous exposure to environmental cadmium (Cd) and renal function with total mortality and cancer incidence. METHODS: The study population comprised 275 residents (aged 40-92 years at baseline) in a Cd-polluted area located on Tsushima Island, Nagasaki, Japan. In the study area, the dietary intake of Cd decreased because the soil of the Cd-polluted rice fields was replaced with new soil between 1980 and 1983. The mortality rate from 1982 to 1997 and cancer incidence from 1985 to 1996 were investigated. Standardized mortality and incidence ratios (SMR and SIR) were calculated by using regional reference rates. The associations of renal function and urinary Cd levels with total mortality and cancer incidence were evaluated with Cox regression models. RESULTS: The SMR for all subjects, and those with a urinary beta2-microglobulin (U-beta2M) concentration > or = 1,000 microg/g creatinine (Cr) and < 1,000 microg/g Cr was estimated at 90 [95% confidence interval (CI) 73-109], 138 (95% CI 101-183) and 66 (95% CI 49-87), respectively. After adjustment for age and other potential confounders, in men, serum beta2M (S-beta2M) (> or = 2.3 mg/l) and in women, serum Cr (> or = 21.2 mg/ 100 ml), relative clearance of beta2M (> or = 21%) and U-beta2M (> or = 1,000 microg/g Cr), were associated with a significantly increased risk of mortality, with hazard ratios exceeding 2.0. After further adjustment for log(U-beta2M), the rate ratio of deaths associated with, in men, increased S-beta2M was 2.53 (95% CI 0.97-6.65) and, in women, increased serum Cr (S-Cr) concentrations was 2.75 (95% CI 1.24-6.14). Urinary Cd concentrations (> or = 10 microg/g Cr) were not significantly associated with mortality. The overall SIR of all malignant neoplasms was 71 (95% CI 44-107). CONCLUSIONS: These findings suggest that renal tubule dysfunction and a reduced glomerular filtration rate are predictors of mortality among persons previously exposed to environmental Cd. However, the results also suggest that overall mortality rates in Cd-polluted areas are not necessarily increased, because of the low mortality among those with no, or only slight, signs of low-molecular weight proteinuria. Overall cancer incidence may not be increased among residents in Cd-polluted areas.

Adult↗
PubMed2001

Clinical significance of the serum surfactant protein D and KL-6 levels in patients with measles complicated by interstitial pneumonia.

UNLABELLED: To examine the value of surfactant protein D and KL-6 as markers for the diagnosis and the severity of interstitial pneumonia caused by measles infection, surfactant protein D, KL-6 and lactic acid dehydrogenase were measured serially in three patients with measles complicated by interstitial pneumonia as compared to ten measles infected patients without interstitial pneumonia. The serum surfactant protein D and KL-6 levels were higher in patients with measles and interstitial pneumonia as compared to those with measles without interstitial pneumonia. In patients with measles and interstitial pneumonia, the respiratory distress and the alveolar-arterial oxygen differences improved after steroid pulse therapy while the serum surfactant protein D level decreased dramatically under the cut-off level and earlier than the KL-6 level. On the contrary, the serum KL-6 level increased transiently and it took longer to decrease below the cut-off level as compared to the pattern observed for serum surfactant protein D. The serum lactic acid dehydrogenase level changes were between those of the surfactant protein D and KL-6 levels. CONCLUSION: Surfactant protein D and KL-6 are easily measured and useful markers for the diagnosis of interstitial pneumonia caused by measles infection. Early decrease of surfactant protein D contrasts with the transient increase of KL-6 levels after prednisolone pulse therapy.

Antigens↗
PubMed2001

Lymphangiogenesis and the vascular endothelial growth factor receptor (VEGFR)-3 in gastric cancer.

Vascular endothelial growth factor C (VEGF-C) is the only factor known to cause lymphangiogenesis. We studied the correlation between VEGF-C and vascular endothelial growth factor receptor-3 (VEGFR-3) expression of 85 primary gastric cancers by reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry, and the results were correlated with the number of lymphatic vessels, stained with anti-VEGFR-3 antibody. RT-PCR and immunohistology demonstrated that VEGF-C was mainly produced from cancer cells, but not from stromal elements. Morphologically, VEGFR-3 expression was detected in the endothelial cells of the stromal lymphatic vessels. There was a statistically positive correlation between the incidence of VEGF-C and VEGFR-3 mRNA expression in the primary tumours (P=0.0002). The number of VEGFR-3-positive lymphatic vessels in VEGF-C mRNA positive tumours was significantly larger than that in VEGF-C-negative tumours. The number of VEGFR-3-positive vessels in the tumour stroma was closely related to the grade of lymphatic invasion of gastric cancer. These results strongly indicate that VEGF-C may induce the proliferation of lymphatic vessels in the stroma of primary gastric cancer via activation of VEGFR-3, expressed on the endothelial cells of lymphatic vessels. In these circumstances, cancer cells can easily invade the lymphatic vessel, because of the increase of the contact points of cancer cells with the lymphatic vessels.

Blotting, Western↗
PubMed2001

Fission yeast living mitosis visualized by GFP-tagged gene products.

The fission yeast Schizosaccharomyces pombe has been used as a model organism to study cell cycle control and dynamic chromosome behavior during anaphase segregation as genetic and cytological approaches are easily amenable. To understand the role of gene products involved in these cellular events, it is important to determine intracellular localization of each gene product during the cell cycle. In this article, visualization in living cells of several gene products involved in cell cycle control and sister chromatid separation is described. The genes tagged with jellyfish green fluorescent protein (GFP) include sad1(+) (encoding a spindle pole body (SPB) protein), atb2(+) (alpha-tubulin), mis6(+) (a kinetochore protein), eat1(+) (a novel actin-like protein localized in the nucleus) and cdc13(+) (a mitotic cyclin). In addition, LacI which is bound to a DNA segment containing LacO repeat sequences integrated near the centromere (cen1) is visualized. These are useful to monitor cell cycle events in living cells.

Cell Cycle↗
PubMed2001

Linking class-switch recombination with somatic hypermutation.

The recent discovery of a molecular link between two apparently different genetic alteration events--class-switch recombination and somatic hypermutation--has led to the idea that the recognition and cleavage of target DNA in these two events might be mediated by similar or identical molecules to those involved in RNA editing. This could mean that the complexity of mammalian genetic information may be enriched by an interplay between RNA editing and DNA modification.

APOBEC-1 Deaminase↗
PubMed2001

Diagnostic value of preoperative RT-PCR-based screening method to detect carcinoembryonic antigen-expressing free cancer cells in the peritoneal cavity from patients with gastric cancer.

BACKGROUND: At present the most reliable method for the diagnosis of peritoneal micrometastasis of gastric cancer is peritoneal wash cytology, but the sensitivity of this method is low. The aim of the present study was to verify whether carcinoembryonic antigen (CEA) reverse transcriptase-polymerase chain reaction (RT-PCR) assay can enhance the sensitivity and specificity of conventional cytology, and to determine how this technique can improve the accuracy of peritoneal recurrence. METHODS: The present study included 230 patients with gastric cancer. Preoperative peritoneal wash was done by a paracentesis, followed by conventional cytology, CEA measurement, and CEA RT-PCR of recovered fluid. RESULTS: The CEA RT-PCR assay yielded 40 (17%) positives, which included none of the 26 patients with benign disease. The incidence of positive cytology and CEA level in wash fluid was 19% and 15%, respectively. Logistic stepwise regression analysis revealed that lymph node status, depth of invasion, venous invasion, and the results of peritoneal cytological examination, and CEA RT-PCR assay were independently related to peritoneal recurrence. The CEA level in the wash fluid was not related to peritoneal recurrence. Peritoneal cytological examination was the most significant predictive factor for peritoneal recurrence with a sensitivity of 46%, specificity of 94% and accuracy of 73%, while the corresponding values of the CEA RT-PCR assay were 31%, 95%, and 73%. Combining cytological examination with CEA RT-PCR assay resulted in a sensitivity rate for peritoneal recurrence of 57%, an 11% improvement over that of cytology alone. CONCLUSION: The data indicate that the use of a combination of CEA RT-PCR and cytological assay is more likely to identify patients who will develop peritoneal recurrence. This may be useful for the classification of patients for the most suitable therapeutic trials.

Adult↗
PubMed2001

Palindromic but not G-rich sequences are targets of class switch recombination.

In order to understand the specificity of sequences or structures recognized by a recombinase involved in class switch recombination (CSR), we examined the relative CSR efficiency of various switch sequences in artificial CSR constructs that undergo CSR in CH12F3-2 murine B lymphoma line. Since CSR recombination is not specific to switch regions of different isotypes or orientation of S sequences, we examined the efficiency of S sequences of non-mammalian species and artificial sequences which lack several characters of mammal switch sequences: chicken S(mu), Xenopus S(mu), telomere, multiple cloning site (MCS) and unrelated negative control sequence. CSR occurred in chicken S(mu) and MCS with significantly higher efficiency than the negative control. A common character of these two sequences is that they are rich in palindrome and stem-loop structures. However, telomeres, which are G-rich and repetitive but not palindromic, could not serve as switch sequences at all. The AT-rich Xenopus S(mu) sequence was inefficient but capable of CSR. CSR breakpoint distribution suggests that the cleavage may take place preferentially in the proximity of the junctions (neck) between the loop and stem in the secondary structure of the single-stranded S sequence, which can be formed by palindromic sequences. The results suggest that the secondary structure of S-region sequences which is transiently formed during transcription may be necessary for recognition by class switch recombinase.

Animals↗
PubMed2001

A possible role of apoptosis for regulating autoreactive responses in systemic lupus erythematosus.

It has been reported that apoptotic cells are increased in the peripheral blood from patients with systemic lupus erythematosus (SLE), where dysfunctions of T helper 1 (Th1) cells are known. In order to study whether apoptosis of Th1 cells is associated with the pathogenesis of SLE, early apoptotic cells in various T-cell subsets were detected using fluorescence-labeled annexin V (AnV). AnV binding was most frequently observed in CD4+CCR5+ T cells, and AnV binding rate (%) in this subset was higher in SLE than in normal controls (14.7 +/- 2.6), although that in active SLE (43.6 +/- 7.3) tended to be lower than that in inactive SLE (48.0 +/- 6.8). CD95/Fas expression was also increased in both active and inactive SLE. In some SLE patients, AnV binding rate changed in inverse proportion to titer of the serum anti-DNA antibody and in proportion to serum complement activity. These data suggest that apoptosis in Th1 cells is important in the pathogenesis of SLE and might play a role in regulating over-activation or autoreactive responses by T cells.

Adult↗
PubMed2001

Decline in the positive rate of human T-lymphotropic virus type-1 (HTLV-1) antibodies among blood donors in Nagasaki.

OBJECTIVE: The aim of this study was to clarify the trend of the HTLV-1 seroprevalence rate among blood donors. METHODS: Samples were screened by the particle agglutination test for HTLV-1 antibodies. MATERIALS: Serum from blood donors was screened. RESULTS: The positive rate of HTLV-1 antibodies among blood donors decreased from 13.14 to 0.81 % over the years from 1928 to 1983. CONCLUSION: A decline over the years in the positive rate of HTLV-1 antibodies among blood donors was revealed.

Adolescent↗
PubMed2001

Prediction of peritoneal micrometastasis by peritoneal lavaged cytology and reverse transcriptase-polymerase chain reaction for matrix metalloproteinase-7 mRNA.

PURPOSE: Peritoneal dissemination is the most common cause of death associated with gastric cancer. In this study, we report the significance of molecular diagnosis of peritoneal dissemination by means of matrix metalloproteinase-7 (MMP-7) reverse transcriptase-PCR (RT-PCR) assay using preoperative peritoneal wash fluid. EXPERIMENTAL DESIGN: Preoperative peritoneal lavage by paracentesis was performed on 152 patients with gastric cancer. The peritoneal lavaged fluid was subjected to RT-PCR analysis with primers specific for MMP-7 and conventional cytological Papanicolaou examination. RESULTS: The MMP-7 RT-PCR assay was able to detect cancer cells at densities even lower than 10 cells/sample. There was no signal of MMP-7 mRNA from mesothelial cells, fibroblasts, peripheral blood, and lavaged fluid from patients with benign disease. Cytological examination and MMP-7 RT-PCR assay results were positive for 27 (18%) and 28 (18%) samples, respectively. The sensitivity for the prediction of peritoneal dissemination by cytology and MMP-7 RT-PCR assay were 46% and 33%, but the combination analysis using both parameters improved the sensitivity rate with 62%. Logistic regression analysis revealed that the cytological examination and MMP-7 RT-PCR assay are independent predictors of peritoneal dissemination. CONCLUSION: The combination of cytological examination and RT-PCR assay of preoperative peritoneal lavaged fluid is a highly efficient and reliable method for the selection of patients for adjuvant i.p. chemotherapy.

Adult↗
PubMed2000

Feeding-induced c-fos expression in the nucleus of the solitary tract and dorsal medullary reticular formation in neonatal rats.

We investigated feeding-associated activation of neurons in the medulla oblongata during the suckling period in rats, using the c-fos gene-encoded protein (Fos) immunohistochemistry. After an isolation from mothers for 12 h, neonates were either breast-fed intensively or further isolated for another 3 h, and sacrificed on postnatal day 1, 3, 5, 7 and 14 (P1-14). In the former pups, Fos-immunoreactive (FI) neurons were predominantly localized in the nucleus of the solitary tract (NST) and in the dorsal medullary reticular formation (RF). The number of FI cells peaked on P5-7 and decreased on P14 in the NST, and increased remarkably on P3 and was consistently high until P14 in the dorsal RF. In contrast, much fewer FI cells were found in the NST and RF in the latter pups. The results indicated that not only the NST but also the dorsal RF were implicated in feeding behavior in the suckled pups.

Aging↗
PubMed2000

Study of charmless hadronic B meson decays to pseudoscalar-vector final states.

We report results of searches for charmless hadronic B meson decays to pseudoscalar( pi(+/-), K+/-, pi(0), or K(0)(S))-vector( rho, K(*), or omega) final states. By using 9.7x10(6) BB pairs collected with the CLEO detector, we report the first observation of B(-)--->pi(-)rho(0), B(0)-->pi(+/-)rho(-/+), and B(-)-->pi(-)omega, which are expected to be dominated by hadronic b-->u transitions. The measured branching fractions are (10.4(+3.3)(-3.4)+/-2.1)x10(-6), (27.6(+8.4)(-7.4)+/-4.2)x10(-6), and (11.3(+3.3)(-2.9)+/-1. 4)x10(-6), respectively. Branching fraction upper limits are set for all of the other decay modes investigated.

Journal Article↗