Biomedical subjects

S Fujii

Publications and source records attributed to S Fujii.

At least 181 records · Page 10Linked to original sources

PubMed1999

Cloning of two cold shock genes, cspA and cspG, from the deep-sea psychrophilic bacterium Shewanella violacea strain DSS12.

We cloned and characterized two cold shock inducible genes from the deep-sea psychrophilic bacterium Shewanella violacea strain DSS12. The cloned genes, designated cspA and cspG, encode proteins each consisting of 70 amino acid residues which show 62 and 67% sequence identity with Escherichia coli CspA and CspG, respectively. AT-rich UP elements were found immediately upstream of the promoter region and the cspA and cspG mRNA contained unusually long 5' untranslated regions like that in the E. coli cspA, cspB, cspG and cspI genes. Following a temperature downshift to 4 degrees C or -1 degree C, the levels of cspA and cspG mRNA increased and the level of expression of cspG was greater than that of cspA both before and after cold shock. These results suggest that CspA and CspG may function as RNA chaperones, the mRNAs encoded by these two genes may be regulated post-transcriptionally and they may function as regulators of other cold shock inducible genes like in E. coli.

Amino Acid Sequence↗

PubMed1999

Walking to work and the risk for hypertension in men: the Osaka Health Survey.

BACKGROUND: It is not known whether physical activity is effective in reducing the risk for hypertension. OBJECTIVE: To investigate the association of the duration of the walk to work and leisure-time physical activity with the risk for hypertension. DESIGN: Prospective cohort study. SETTING: Work site in Osaka, Japan. PARTICIPANTS: 6017 Japanese men 35 to 60 years of age with systolic blood pressure less than 140 mm Hg, diastolic blood pressure less than 90 mm Hg, normal glucose intolerance, and no history of hypertension or diabetes at baseline. MEASUREMENTS: Data on physical activity were obtained by using questionnaires. Blood pressure was measured by using a standard technique; a value of at least 160/95 mm Hg was used to diagnose hypertension. RESULTS: During 59,784 person-years of follow-up, 626 cases of hypertension were confirmed. The duration of the walk to work was associated with a reduction in the risk for incident hypertension; multivariate-adjusted relative risks were 1.00 for a walk of 10 minutes or less (reference category), 0.88 (95% CI, 0.75 to 1.04) for an 11- to 20-minute walk, and 0.71 (CI, 0.52 to 0.97) for a walk of 21 minutes or more (P for trend = 0.02). For every 26.3 men who walk more than 20 minutes to work, one case of hypertension will be prevented. CONCLUSIONS: Walking to work and other types of physical activity decreased the risk for hypertension in Japanese men. Regular exercise can prevent hypertension.

Adult↗

PubMed1999

Expression of cyclins and cyclin-dependent kinases in smooth muscle tumors of the uterus.

To investigate the cell cycle regulatory mechanisms involved in the growth of smooth muscle tumors, we studied the expression of Ki-67, cyclins E and A, and their catalytic partners, the cyclin-dependent kinases cdk2 and cdc2 by using tissue specimens from benign and malignant smooth muscle tumors. These included 20 cases of usual leiomyoma (UL), 18 of cellular leiomyoma (CL), 8 of bizarre leiomyoma (BL), 8 of uncertain malignant potential tumors (UMP) and 20 of leiomyosarcoma (LMS). The proliferation rate detected by Ki-67 was low in normal myometrium and leiomyomas (UL, CL and BL), but it was markedly increased in LMS. The expression of the cyclins (E and A) and cdks (cdk2 and cdc2) was also low in normal myometrium and leiomyomas. However, the expression of these factors was markedly increased in LMS. In addition, a survival analysis using Log-rank test, revealed that LMSs with positive staining for cyclin A and with diffusely staining for cyclin E were associated with significantly shorter survival. Our results suggest that expression of cyclins and cdks may be involved in the growth control of uterine smooth muscle tumors.

Adult↗

PubMed1999

DNA replication errors produced by the replicative apparatus of Escherichia coli.

It has been hard to detect forward mutations generated during DNA synthesis in vitro by replicative DNA polymerases, because of their extremely high fidelity and a high background level of pre-existing mutations in the single-stranded template DNA used. Using the oriC plasmid DNA replication in vitro system and the rpsL forward mutation assay, we examined the fidelity of DNA replication catalyzed by the replicative apparatus of Escherichia coli. Upon DNA synthesis by the fully reconstituted system, the frequency of rpsL-mutations in the product DNA was increased to 1.9x10(-4), 50-fold higher than the background level of the template DNA. Among the mutations generated in vitro, single-base frameshifts predominated and occurred with a pattern similar to those induced in mismatch-repair deficient E. coli cells, indicating that the major replication error was slippage at runs of the same nucleotide. Large deletions and other structural alterations of DNA appeared to be induced also during the action of the replicative apparatus.

Base Pairing↗

PubMed1999

Activated dendritic cells from bone marrow cells of mice receiving cytokine-expressing tumor cells are associated with the enhanced survival of mice bearing syngeneic tumors.

Dendritic cells (DCs), which phagocytose antigens and subsequently proliferate and migrate, may be the most powerful antigen-presenting cells that activate naive T cells. To determine their role in the immune response to tumors, we used WEHI-3B murine leukemia cells transduced with adenovirus vectors expressing cytokines. We found that mixtures of irradiated cells expressing granulocyte-macrophage colony-stimulating factor (GM-CSF) plus those expressing interleukin-4 (IL-4) or tumor necrosis factor alpha (TNFalpha) protected mice against WEHI-3B-induced leukemias. When bone marrow mononuclear cells (BMMNCs) obtained from mice that had been injected with irradiated, cytokine-expressing tumor cells were injected into tumor-bearing mice, the survival of the latter was significantly prolonged; the longest survival was observed in mice receiving BMMNCs containing an increased number of DCs from animals injected with a mixture of tumor cells expressing GM-CSF with those expressing IL-4. Assay for antileukemic effects in spleen of the latter animals showed specific antitumor cytotoxicity against WEHI-3B, suggesting that DCs from donor mice activate specific T cells in the tumor-bearing recipients. These results suggest that the infusion of syngeneic BMMNCs stimulated with cytokine-expressing tumor cells may be effective in treating certain types of tumors.

Adenoviridae↗

PubMed1999

Contribution of hydrogen bonds to the conformational stability of human lysozyme: calorimetry and X-ray analysis of six Ser --> Ala mutants.

To further examine the contribution of hydrogen bonds to the conformational stability of the human lysozyme, six Ser to Ala mutants were constructed. The thermodynamic parameters for denaturation of these six Ser mutant proteins were investigated by differential scanning calorimetry (DSC), and the crystal structures were determined by X-ray analysis. The denaturation Gibbs energy (DeltaG) of the Ser mutant proteins was changed from 2.0 to -5.7 kJ/mol, compared to that of the wild-type protein. With an analysis in which some factors that affected the stability due to mutation were considered, the contribution of hydrogen bonds to the stability (Delta DeltaGHB) was extracted on the basis of the structures of the mutant proteins. The results showed that hydrogen bonds between protein atoms and between a protein atom and a water bound with the protein molecule favorably contribute to the protein stability. The net contribution of one intramolecular hydrogen bond to protein stability (DeltaGHB) was 8.9 +/- 2.6 kJ/mol on average. However, the contribution to the protein stability of hydrogen bonds between a protein atom and a bound water molecule was smaller than that for a bond between protein atoms.

Alanine↗

PubMed1999

Possible role of calponin h1 as a tumor suppressor in human uterine leiomyosarcoma.

BACKGROUND: Calponin h1, a basic actin-binding protein capable of inhibiting smooth muscle contraction, is a constitutive element of smooth muscle cells. However, in leiomyosarcoma (a type of smooth muscle neoplasm of the uterus), reduced expression of calponin h1 is observed, as we have reported previously. In this study, we sought to assess the effects (in vitro and in vivo) of increasing calponin h1 expression in leiomyosarcoma cells. METHODS: A plasmid containing a human calponin h1 complementary DNA and a bacterial neomycin-resistance gene was transfected into the human leiomyosarcoma cell lines SKN and SK-LMS-1 by electroporation. Southern blotting, reverse transcription-polymerase chain reaction analysis, western blotting, and immunohistochemistry were used to confirm DNA transfer and expression of the calponin h1 protein in neomycin-resistant clones. We characterized the morphology of calponin h1-transfected cells, and we evaluated their proliferative activity and tumorigenicity by use of a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay, an anchorage-independent growth assay, and a nude mouse tumorigenicity assay. RESULTS: The morphology of calponin h1-transfected cells in culture resembled that of cultured normal myometrial smooth muscle cells. With SK-LMS-1 cells, proliferation of calponin h1-transfection cells was reduced to 69% of control; with SKN cells, calponin h1 transfection reduced proliferation to 70% of control. In assays of anchorage-independent growth and in vivo tumorigenicity, both growth and tumorigenicity were statistically significantly reduced in calponin h1-transfected leiomyosarcoma cells. CONCLUSIONS: Calponin h1 may function as a tumor suppressor in leiomyosarcoma. Clinically, transfer of a calponin h1 complementary DNA into poorly differentiated leiomyosarcoma cells may be of potential therapeutic value through induction of a normal, differentiated cellular phenotype.

Animals↗

PubMed1999

Presentation of tumor antigens by phagocytic dendritic cell clusters generated from human CD34+ hematopoietic progenitor cells: induction of autologous cytotoxic T lymphocytes against leukemic cells in acute myelogenous leukemia patients.

The use of antigen-presenting dendritic cells (DCs) is currently proposed for tumor immunotherapy through generation of CTLs to tumor antigens in cancer patients. In this study, DCs were differentiated using granulocyte-macrophage colony-stimulating factor and tumor necrosis factor-alpha from CD34+ hematopoietic progenitor cells that had been mobilized into the peripheral blood. To use the phagocytic activity of DCs for processing and presentation of tumor antigens, we established DC clusters containing immature DCs by preserving proliferating cell clusters without mechanical disruption. After an 11-day culture, the developed clusters contained not only typical mature DCs but also immature DCs that showed active phagocytosis of latex particles, suggesting that the clusters consisted of DCs of different maturational stages. These heterogeneous clusters could present an exogenous protein antigen, keyhold limpet hemocyanin, to both CD4+ and CD8+ T lymphocytes. Furthermore, in three acute myelogeneous leukemia patients, clusters pulsed with autologous irradiated leukemic cells could also induce antileukemic CTLs. The mechanical disruption of clusters abrogated the induction of CTLs to leukemic cells as well as to hemocyanin. This observation gives an important information for the use of heterogeneous DC clusters derived from autologous peripheral blood CD34+ cells in the case of immunotherapy for leukemia.

Acute Disease↗

PubMed1999

Role of nitric oxide in pathogenesis of herpes simplex virus encephalitis in rats.

The role of nitric oxide (NO) in the pathogenesis of viral encephalitis was investigated by using an experimental model of herpes simplex virus type 1 (HSV-1) encephalitis in Lewis rats. The expression of inducible NO synthase (iNOS) mRNA determined by Northern blotting was observed first in the olfactory bulb and the brain stem on day 5 after intranasal inoculation of HSV-1, and thereafter iNOS mRNA was detected in other brain regions, i.e., cerebrum and cerebellum. In various parts of the brain, excessive NO production was identified by electron spin resonance spectroscopy. The temporal and spatial patterns of iNOS expression coincided with those of viral propagation, as demonstrated by polymerase chain reaction for HSV-1 gene expression as well as by the plaque-forming assay. Immunohistochemical study determined that iNOS was localized mainly in monocyte-derived macrophages. Treatment of virus-infected animals with the NOS inhibitor Nomega-monomethyl-l-arginine (l-NMMA), but not Nomega-monomethyl-d-arginine, significantly ameliorated not only clinical symptoms such as paralysis and seizures but also mortality. Virus yield from brain tissue was not affected by l-NMMA treatment. It is of interest that increased expression of the antioxidant enzyme heme oxygenase-1 was observed in the HSV-1-infected brain; this increased expression was strongly inhibited by l-NMMA treatment. These data suggest that the high level of NO produced by iNOS is a pathogenic factor in HSV-1-induced encephalitis in rats.

Animals↗

PubMed1999

A'-form RNA double helix in the single crystal structure of r(UGAGCUUCGGCUC).

Here we demonstrate the presence of the A'-RNA conformation using the single crystal structure of a tridecamer: r(UGAGCUUCGGCUC). The average A'-RNA conformation deduced from X-ray fiber diffraction data had only been available previously, but now the presence of the A'-RNA conformation has been found in a single crystal structure for the first time. Statistical analysis showed that the A'-RNA conformation is distinguishable from the A-RNA conformation in a plot of the major groove width against the base pair inclination angle. The major groove of the A'-RNA conformation is wide enough to accommodate a protein or peptide while that of the A-RNA conformation is too narrow to do so. The presence of the A'-RNA conformation is significant for protein-RNA interaction.

Crystallization↗

PubMed1999

Clear cell carcinoma has an expression pattern of cell cycle regulatory molecules that is unique among ovarian adenocarcinomas.

BACKGROUND: The purpose of this study was to identify biologic differences between ovarian clear cell carcinoma and other ovarian adenocarcinomas by comparing the expression of cell cycle regulatory molecules and by analyzing the survival of the patients. METHODS: In 51 cases of epithelial ovarian carcinoma, the expression of the cell proliferation marker Ki-67 and that of the cell cycle regulatory molecules p53, p16, p21, p27, cyclin E, and cyclin A was studied using immunohistochemical techniques. The correlations among clinical stage, histologic subtype, labeling index for Ki-67, and expression of these cell cycle regulators were examined statistically. Multivariate survival analysis was performed using these factors in the Cox proportional hazards model. RESULTS: Clear cell carcinoma revealed such trends as low expression of both p53 and cyclin A and significantly increased expression of both p21 and cyclin E (compared with the other histologic subtypes). In all ovarian carcinomas, a very strong positive correlation (correlation coefficient 0.79; P < 0.0001) between p53 positive staining and cyclin A positive staining and a weak positive correlation (correlation coefficient 0.47; P < 0.01) between p21 positive staining and cyclin E positive staining were recognized at the level of expression of cell cycle regulatory molecules. Clinical stage was the only independent predictive factor for the survival of the patients. CONCLUSIONS: Among ovarian adenocarcinomas, clear cell carcinoma exhibits a unique pattern of expression of cell cycle regulatory molecules, though in this study the survival of the patients did not correlate with histologic subtype, only with clinical stage.

Adenocarcinoma↗

PubMed1999

A case of clitoral metastasis without skin involvement from rectal cancer.

An 84-year-old woman visited a private dermatologist and gynecologist due to pain in the external genitals. However, no abnormality was found. She was referred to a surgeon in our hospital to clarify the etiology of the pain. Rectal cancer and liver metastatic tumor were detected, and the rectal cancer was resected. However, the pain increased after the operation and she was referred to our department. No macroscopic abnormalities of the external genitals were found. However, a vaginal examination could not be performed due to severe pain. By local examination under anesthesia, enlargement of the clitoris was detected. A simple clitoridectomy was performed. Histological examination revealed that the clitoral tumor was metastatic cancer originating from rectal cancer.

Adenocarcinoma↗

PubMed1999

Frequent occurrence of loss of heterozygosity among tumor suppressor genes in uterine leiomyosarcoma.

OBJECTIVE: Leiomyosarcoma of the uterus is a rare smooth muscle tumor; it is extremely malignant and the rates of local recurrence and metastasis are high. Since tumor suppressor genes are commonly altered in malignant tumors, it is possible that mutations in such genes are involved in the development of uterine leiomyosarcoma. METHODS: Fifty-five patients (37-70 years of age) diagnosed as having smooth muscle tumors of the uterus were selected. DNA was extracted from four or five 8-microm-thick consecutive tissue sections of each smooth muscle tumor from the paraffin-embedded blocks. Loss of heterozygosity (LOH) was investigated at nine loci within or close to tumor suppressor genes (TP53, RB1, DCC, NM23, WT1, D14S267, P16, DPC4, PTCH). RESULTS: Nineteen of twenty leiomyosarcomas revealed at least one instance of LOH among eight of the nine markers tested (one locus showed no LOH at all). In fact, 11 of the 20 cases exhibited two or more instances of LOH and, of the remaining 9 cases, 4 showed a point mutation of p53 in addition to an alteration in one of the 9 markers, while one exhibited a p53 mutation only. CONCLUSION: An accumulation of genetic alterations among tumor suppressor genes may play a key role in the tumorigenesis and progression of uterine leiomyosarcoma.

Adult↗

PubMed1999

Growth and development in Arabidopsis thaliana through an entire life cycle under simulated microgravity conditions on a clinostat.

The effects of simulated microgravity conditions produced by a horizontal clinostat on the entire life cycle of Arabidopsis thaliana ecotype Columbia and Landsberg erecta were studied. Horizontal clinorotation affected little germination of seeds, growth and development of rosette leaves and roots during early vegetative growth stage, and the onset of the bolting of inflorescence axis and flower formation in reproductive growth stage, although it suppressed elongation of inflorescence axes. The clinorotation substantially reduced the numbers of siliques and seeds in Landsberg erecta, and completely inhibited seed production in Columbia. Seeds produced in Landsberg erecta on the clinostat were capable of germinating and developing rosette leaves normally on the ground. On the other hand, growth of pin formed mutant (pin/pin) of Arabidopsis ecotype Enkheim, which has a unique structure of inflorescence axis with no flower and extremely low levels of auxin polar transport activity, was inhibited and the seedlings frequently died during vegetative stage on the clinostat. Seed formation and inflorescence growth of the seedlings with normal shape (pin/+ or +/+) were also suppressed on the clinostat. These results suggest that the growth and development of Arabidopsis, especially in reproductive growth stage, is suppressed under simulated microgravity conditions on a clinostat. To complete the life cycle probably seems to be quite difficult, although it is possible in some ecotypes.

Arabidopsis↗

PubMed1999

Growth and development, and auxin polar transport in higher plants under microgravity conditions in space: BRIC-AUX on STS-95 space experiment.

The principal objectives of the space experiment, BRIC-AUX on STS 95, were the integrated analysis of the growth and development of etiolated pea and maize seedlings in space and a study of the effects of microgravity conditions in space on auxin polar transport in these segments. Microgravity significantly affected the growth and development of etiolated pea and maize seedlings. Epicotyls of etiolated pea seedlings were the most oriented toward about 40 to 60 degrees from the vertical. Mesocotyls of etiolated maize seedlings were curved at random during space flight but coleoptiles were almost straight. Finally the growth inhibition of these seedlings in space was also observed. Roots of some pea seedlings grew toward to the aerial space of Plant Growth Chamber. Extensibilities of cell walls of the third internode of etiolated pea epicotyls and the top region of etiolated maize coleoptiles, which were germinated and grown under microgravity conditions in space, were significantly low as compared with those grown on the ground of the earth. Activities of auxin polar transport in the second internode segments of etiolated pea seedlings and coleoptile segments of etiolated maize seedlings were significantly inhibited and promoted, respectively, under microgravity conditions in space. These results strongly suggest that auxin polar transport as well as the growth and development of plants is controlled under gravity on the earth.

Biological Transport↗

PubMed1999

Glomerular hypertension as one cause of albuminuria in type II diabetic patients.

AIMS/HYPOTHESIS: Results from animal models of glomerular hypertension have suggested that this disorder is one cause of albuminuria in diabetic nephropathy. We evaluated this hypothesis clinically. METHODS: The subjects were 20 patients with Type II (non-insulin-dependent) diabetes mellitus but without uraemia or hypertension: 8 had normoalbuminuria and 12 had albuminuria (> or = 20 micrograms/min). In the 2-week study, patients were on a diet with ordinary amounts of sodium for 1 week and on a sodium-restricted diet for 1 week. Urinary excretion of sodium and albumin and the systemic blood pressure were measured daily. Intrarenal haemodynamics, in terms of the glomerular pressure and resistance of afferent and efferent arterioles, were calculated from renal clearance, the plasma total protein concentration, and the pressure-natriuresis relation. In 8 of the 12 patients with albuminuria, an angiotensin-converting enzyme inhibitor, cilazapril, was given orally (2 mg/day) and the 2-week study was repeated. RESULTS: In patients with albuminuria, resistance of efferent arterioles and the glomerular pressure were higher than in patients with normoalbuminuria (glomerular pressure, 53 +/- 5 vs 43 +/- 5 mmHg, means +/- SD, p < 0.001). Urinary excretion of albumin correlated (n = 20, r = 0.675, p < 0.001) with the glomerular pressure but not with systemic pressure. The increased glomerular pressure and the albuminuria were decreased by cilazapril but systemic pressure was not. CONCLUSIONS/INTERPRETATION: These findings are consistent with the hypothesis that glomerular hypertension is present in Type II diabetic patients with early nephropathy and can cause albuminuria.

Adult↗

PubMed1999

Clinical application of a new assisted hatching method using a piezo-micromanipulator for morphologically low-quality embryos in poor-prognosis infertile patients.

OBJECTIVE: To assess the effect of a assisted hatching technique using a piezo-micromanipulator on pregnancy rates in poor-prognosis infertile patients. DESIGN: A prospective randomized study. SETTING: The Infertility and IVF unit of the Kyoto University Hospital. PATIENT(S): Infertile patients who had been treated for >4 years and failed in previous IVF trials at least twice. INTERVENTION(S): Two hundred forty-eight IVF cycles from 173 patients were divided into two groups: cycles with the transfer of embryos treated by assisted hatching and cycles with the transfer of nontreated embryos. Each group was subdivided into two groups according to embryo morphology: cycles in which three or two morphologically good-quality embryos were transferred and cycles in which one or no morphologically good-quality embryos were transferred. Assisted hatching was performed by a piezo-micromanipulator. MAIN OUTCOME MEASURE(S): The clinical pregnancy rates and implantation rates. RESULT(S): The clinical pregnancy and implantation rates were significantly higher in the assisted hatching group of patients with three or two good-quality embryos than in the other three groups. CONCLUSION(S): The assisted hatching using a piezo-micromanipulator improved the pregnancy and implantation rates in poor-prognosis infertile patients with good-quality embryo transfer but had no effect in patients with low-quality embryo transfer.

Adult↗

PubMed1999

Tranilast inhibits the proliferation of human coronary smooth muscle cell through the activation of p21waf1.

Restenosis after percutaneous transluminal coronary angioplasty (PTCA) occurs due to vascular smooth muscle cell proliferation and migration. Recently, tranilast, an anti-allergic drug, has been used for the prevention of restenosis after PTCA. To determine the molecular mechanism involved, the effect of tranilast on the proliferation of human coronary smooth muscle cells (SMCs) was investigated. Tranilast arrested the proliferation of human coronary SMCs at the G0/G1 phase of the cell cycle. In association with this inhibitory effect, tranilast increased p21waf1 and p53 tumor suppressor factor, and decreased cyclin-dependent kinase 2 (CDK2) activity. These results suggest that tranilast inhibits the proliferation of human coronary SMCs during restenosis after PTCA via an induction of p21waf1 and p53. Tranilast may thus allow us to prevent restenosis after PTCA by interfering with this mechanism.

Anti-Allergic Agents↗