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Biomedical subjects

S Fujimura

Publications and source records attributed to S Fujimura.

At least 19 recordsLinked to original sources
PubMed2006

Detection of Lactobacillus gasseri OLL2716 strain administered with yogurt drink in gastric mucus layer in humans.

In animal models and human trials, Lactobacillus gasseri OLL2716 (LG21) strain suppressed Helicobacter pylori colonization in the stomach. The aim of the present study was to clarify whether orally administered LG21 strain can enter the gastric mucus layer. Biopsy samples were taken from the gastric antrum and corpus of two healthy volunteers (H. pylori infected and non-infected) who drank yogurt supplemented with LG21 strains. DNA of LG21 and H. pylori in the mucus layer was detected using the laser-assisted microdissection and non-contact pressure catapulting (LMPC) method and the semi-nested PCR method with primer sets of RNA helicases of superfamily II gene-Insertion sequence for LG21 strain and those of ureA gene for H. pylori. In the volunteer with H. pylori infection, DNA fragments of LG21- and H. pylori-specific regions from both antrum and corpus were amplified, whereas in a non-infected volunteer, only the LG21 DNA from the antrum was amplified. The present study demonstrated that LG21 strains administered through a yogurt drink can enter into the gastric mucus layer. Our novel method may be useful in studying gastric probiotics for H. pylori infection.

Gastric Mucosa↗
PubMed2006

Gene expression of myostatin during development and regeneration of skeletal muscle in Japanese Black Cattle.

Myostatin is a specific negative regulator of skeletal muscle growth and is regarded as one of the most important factors for myogenesis. The aim of the current study was to analyze the developmental change in the gene expression of myostatin and an adipogenic transcription factor (peroxisome proliferator-activated receptor lambda2) in the semitendinosus muscle of Japanese Black Cattle throughout the whole life cycle. An additional aim was to compare the temporal expression patterns of myostatin and relevant myogenic regulatory factors (MRF) mRNA during muscle regeneration after frostbite injury at 16 mo of age. The developmental pattern of myostatin gene expression exhibited 2 peaks: the greatest expression occurred in utero (P <0.05) and the second greatest occurred at 16 mo of age (P <0.05). The greatest level of peroxisome proliferator-activated receptor lambda2 expression was observed at 16 mo of age (P <0.05), which paralleled myostatin expression. During frostbite-induced muscle regeneration, gene expression for myostatin and 4 MRF; i.e., Myf5, MyoD, myogenin and MRF4, showed contrasting responses. Myostatin mRNA dramatically declined by 68.1 and 82.6% at 3 and 5 d after injury (P <0.05), respectively, which paralleled its protein expression, and was restored at 10 d. In contrast, the expressions of all 4 MRF mRNA were low initially but increased by 5 d after injury (P <0.05) and then remained constant or decreased slightly. These results suggest that myostatin may play a role in muscle marbling in the fattening period by decreasing myogenesis and increasing adipogenesis, and that the interaction between myostatin and MRF genes may take place at an early stage of skeletal muscle regeneration.

Animals↗
PubMed2004

Proliferation of cultured human gingival fibroblasts caused by isradipine, a dihydropyridine-derivative calcium antagonist.

As it was reported earlier that isradipine, a Ca superset 2+ antagonist of dihydropyridine derivative class, caused regression of nifedipine-induced hyperplasia of human gingiva, experiments were performed to examine whether or not isradipine would solely inhibit the proliferation of cultured gingival fibroblasts. Normal human gingival fibroblast Gin-1 cells were used to test the impact of this medication. Fibroblast proliferation in the presence of isradipine (10 microM) was examined by using the reagent water-soluble tetrazolium-1 (WST-1). The level of basic fibroblast growth factor (bFGF) in the cell-free supernatant of each well was determined by using an enzyme-linked immunosorvent assay (ELISA) kit. The production of type I collagen was assayed by ELISA. Isradipine significantly enhanced the cell proliferation from the second day of the culture period. Also, isradipine raised the level of bFGF in the culture medium. The same concentration, also significantly enhanced the production of type I collagen. In conclusion, we were able to prove that isradipine causes the proliferation of cultured gingival fibroblasts as well as other dihydropyridine-derivative Ca superset 2+ antagonists do. In order to prevent the gingival overgrowth, it is advisable to be very careful in the use of isradipine as a therapy for hypertension and other indications.

Calcium↗
PubMed2004

Helicobacter pylori in Japanese river water and its prevalence in Japanese children.

AIMS: The major transmission route of Helicobacter pylori remains unclear. In this study, we examined H. pylori in the environmental waters in Japan. METHODS AND RESULTS: A total of 24 water samples were collected from the upper, middle and downstream reaches of four Japanese rivers. Helicobacter pylori-specific DNA was examined using nested PCR. In addition, 224 children who lived near one river were studied by the stool antigen test for H. pylori prevalence. Helicobacter pylori DNA was detected in the water from the middle and downstream reaches of all four rivers, but not in the upper reaches. Helicobacter pylori was not found in cultured water samples with positive PCR results. Helicobacter pylori prevalence in the children examined was 9.8% for those living near the middle reaches and 23.8% nearby downstream, both of which were higher than the value in an area distant from the river (0%) (both, P < 0.01). CONCLUSIONS: Difference in H. pylori prevalence in the children may be related to the presence of H. pylori in the river. The results of this study showed that H. pylori DNA is frequently present in river water from the middle and downstream reaches in which the human biosphere is embedded. SIGNIFICANCE AND IMPACT OF THE STUDY: It is suggested that river water in the natural environment could be a risk factor for H. pylori transmission.

Child↗
PubMed2004

[Perforating mediastinal mature teratoma associated with acute cardiac tamponade; report of a case].

We report a case of the mediastinal teratoma associated with acute cardiac tamponade followed by emergency operation. This tumor causes a variety of complications, but reports of acute cardiac tamponade have been rare. 20-year-old male admitted into our hospital with complaint of the chest pain, who was diagnosed with mediastinal tumor. She was admitted due to sudden fever up, and 5 days after admission, the complaint of severe epigastralgia and abdominal swelling were occurred. A chest X-ray film and chest computed tomography (CT) revealed cardiac tamponade. We carried out emergency surgical pericardial drainage and extirpation of the tumor. The tumor was composed of cystic part involving of dark green fluid macroscopically. The amylase level in this fluid was 42 U/l. We observed a small hole on the pericardial sac beside the base of ascending aorta. The amylase level in pericardial effusion was 19 U/l. Histopathological diagnosis was mature teratoma perforating into pericardiac sac, which included skin, bronchus and pancreatic tissue. We concluded that the progress of the tumor and the mechanical inflammation were major cause of perforation of the tumor into the pericardial sac, and autodigestion by enzyme from pancreas was minor cause of perforation.

Acute Disease↗
PubMed2003

Comparison of ability of apoptosis induction by lipopolysaccharide of Porphyromonas gingivalis with Escherichia coli.

We compared effects of Porphyromonas gingivalis LPS with Escherichia coli LPS to the murine peritoneal macrophage. E. coli LPS possessed a threshold dose between 100 micro g and 10 micro g, the higher dose induced apoptosis at the murine peritoneal macrophage while the lower dose did not. The ability of apoptosis induction at the murine peritoneal macrophage of P. gingivalis LPS was weaker than E. coli LPS. P. gingivalis LPS did not induce significant apoptosis in all tested dose. However, the morphology of the peritoneal macrophage treated by P. gingivalis LPS was obviously different from that of the unstimulated cells.

Animals↗
PubMed2003

Purification and partial characterization of a dipeptidyl peptidase from Prevotella intermedia.

A peptidase hydrolyzed X-Pro-p-nitroanilide was purified from the cell extract of Prevotella intermedia ATCC 25611 by ion-exchange chromatography and hydrophobic interaction chromatography. The purified enzyme exhibited a molecular size of 74 kDa from sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the maximum enzyme activity was found between pH 7.0 and pH 7.5. This peptidase was a serine enzyme and hydrolyzed Lys-Pro-p-nitroanilide, Arg-Pro-p-nitroanilide, and Ala-Pro-p-nitroanilide, but Lys-Ala-p-nitroanilide was not split. The enzyme may be classified as a dipeptidyl peptidase IV.

Amino Acid Sequence↗
PubMed2002

Detection of Helicobacter pylori in cow's milk.

AIMS: To investigate the existence of Helicobacter pylori in cow's milk as one of the foods which most Japanese children eat. METHODS AND RESULTS: Detection of H. pylori was demonstrated by the semi-nested polymerase chain reaction (PCR), a culture method and electron microscopy. Semi-nested PCR demonstrated the ureA gene of H. pylori in 13 of 18 (72.2%) raw milk samples and in 11 of 20 (55%) commercial pasteurized milk samples. Helicobacter pylori binding immunomagnetic beads with H. pylori-specific goat anti-H. pylori antibody was shown by electron microscopy in both raw and pasteurized milk positive for the ureA gene. Helicobacter pylori was cultured in one raw milk sample, whereas it was not cultured in pasteurized milk samples. CONCLUSIONS, SIGNIFICANCE AND IMPACT OF THE STUDY: There is a possibility that cow's milk is a transmission vehicle in childhood H. pylori infection, although we failed to confirm the survival of H. pylori in pasteurized milk.

Animals↗
PubMed2001

Germinal center-associated nuclear protein (GANP) has a phosphorylation-dependent DNA-primase activity that is up-regulated in germinal center regions.

Antigen stimulation induces a rapid proliferation of B cells for expansion of specific B cell clones and their further differentiation into antibody-producing cells in germinal centers of T-dependent antigen-immunized mice. Previously, we identified a 210-kDa germinal center-associated nuclear protein (GANP) that is up-regulated selectively in germinal centers and carries an MCM-binding domain in the carboxyl-terminal side. In addition, here, we found a region (from 414 to 550 aa) in GANP molecule that is slightly similar to the known DNA-primase component p49. The recombinant GANP fragment covering this region synthesizes RNA primers for extension by DNA polymerase I with single-stranded DNA templates in vitro. GANP DNA-primase activity is controlled by phosphorylation at Ser(502) that is induced by CD40-mediated signaling in vitro and in the germinal center B cells stimulated with antigen in vivo. Overexpression of ganp cDNA in Daudi B cells caused the increased DNA synthesis more than the levels of the mock-transfectants. These evidences suggested that the novel DNA-primase GANP is involved in regulation of cell proliferation of antigen-driven B cells in germinal centers.

Acetyltransferases↗
PubMed2001

A case-control study for evaluating the efficacy of mass screening program for lung cancer in Miyagi Prefecture, Japan.

BACKGROUND: In Miyagi Prefecture, Japan, a mass screening program for lung cancer has been conducted since 1982 (miniature chest X-ray for all screenees and sputum cytology for those with a smoking index > or = 600) [smoking index 600 = 30 pack years, the average number of cigarettes smoked per day multiplied by the number of years of regular smoking]. Over 1500 lung carcinomas, including 250 roentgenographically occult lung tumors, were detected and treated up to 1999. In the current study, a nested case-control study was conducted in the population that was screened in 1989 to evaluate the efficacy of the screening program for lung cancer. METHODS: To reduce self-selection bias, the source population was defined as screenees with negative results in 1989 (284,226 individuals). In the population, 474 individuals died of lung carcinoma during 1992-1994. After exclusion, 328 patients who died of primary lung carcinoma at between ages 40 years and 79 years were defined as the cases. Six controls were supposed to be selected in the source population for each case and matched by gender, year of birth, municipality, and smoking habits. Controls who had died or moved before the matched case was diagnosed were excluded. Finally, 328 cases and 1886 controls were selected. Screening histories were compared, and odds ratios were calculated using conditional logistic regression analysis. RESULTS: Within the 12 months before diagnosis, 241 of 328 cases (73.5%) had attended the screening compared with 1557 of 1886 controls (82.6%). The smoking-adjusted odds ratio was 0.54 (95% confidence interval, 0.41-0.73). CONCLUSIONS: The mass screening program for lung cancer in Miyagi Prefecture was capable of reducing by 46% the risk of death from carcinoma of the lung.

Adult↗
PubMed2001

Specific recognition of cytosolic thymidine kinase in the human lung tumor by monoclonal antibodies raised against recombinant human thymidine kinase.

Anti-TK monoclonal antibodies (mAbs) were raised against recombinant human cytosolic thymidine kinase (rhTK) and characterized by Western immunoblotting, enzyme-linked immunosorbent assay (ELISA) and immunostaining of tumor cells. Twenty-three clones of TK mAbs were characterized to recognize specifically not only rhTK produced by Escherichia coli but also TK subunit of 25 kDa in human lung cancer. The anti-TK mAbs reacted specifically with cytosolic TK but not with mitochondrial TK. Only one clone of the mAbs inhibited the catalytic activity of TK. By solid phase sandwich enzyme immunoassay using these mAbs, we could quantitate the cytosolic TK content in tissues. Immunohistochemical staining analysis using one of the TK mAbs showed that human lung adenocarcinoma and squamous cell carcinoma exhibited much higher staining intensity than stromal cells. These mAbs are useful for biochemical studies on the regulation of human TK in proliferating cells such as tumor cells and for diagnosis of highly proliferating tumors.

Adenocarcinoma↗
PubMed2001

Heterogeneous nuclear ribonucleoprotein B1 as early cancer biomarker for occult cancer of human lungs and bronchial dysplasia.

Heterogeneous nuclear ribonucleoprotein (hnRNP) B1 is a RNA-binding protein of Mr 37,000. We previously reported that hnRNP B1 was specifically overexpressed in the nuclei of human lung cancer cells, particularly in squamous cell carcinoma (E. Sueoka et al., Cancer Res., 59: 1404-1407, 1999). We extended this study to determine whether hnRNP BL was overexpressed in roentgenographically occult cancers of the lungs and premalignant lesions of squamous cell carcinomas, such as bronchial dysplasia. The additional object of our study was to examine the usefulness of hnRNP B1 as a potential diagnostic marker for squamous cell carcinoma of various organs, such as the oral cavity and esophagus in humans. Surgically resected specimens of bronchial dysplasia, lung cancers, and various human squamous cell carcinomas, collected at two hospitals in Japan, were subjected to immunohistochemical staining with anti-hnRNP B1 antibody. Overexpression of hnRNP B1 protein was observed in 100% of stage I lung cancer tissues, but it was not found in normal bronchial epithelium. Squamous cell carcinoma of the lungs showed stronger staining than other histological types, and elevation of hnRNP B1 was found in both roentgenographically occult lung cancers and bronchial dysplasia. Furthermore, cytological examination with anti-hnRNP B1 antibody detected cancer cells in sputum, suggesting the potential of hnRNP B1 protein as a new biomarker for the very early stage of lung cancer in humans. Because strong staining of hnRNP B1 was also observed in various squamous cell carcinomas of oral and esophageal tissues as shown in our recent reports, overexpression of hnRNP B1 seems to be a common event in the carcinogenic processes of squamous cell carcinoma. These results suggest that hnRNP B1 protein could be a useful diagnostic biomarker for both the very early stages of lung cancer and various squamous cell carcinomas in humans.

Adenocarcinoma↗
PubMed2001

Comparative in-vitro activity of carbapenem antibiotics against respiratory pathogens isolated between 1999 and 2000.

We investigated the antibacterial activity of 12 antibiotics, inclusive of four carbapenems, against 167 strains of respiratory pathogens isolated between 1999 and 2000. Thirty strains of methicillin-susceptible Staphylococcus aureus (MSSA), 28 strains of methicillin-resistant S. aureus (MRSA), 11 strains of penicillin-susceptible Streptococcus pneumoniae (PSSP), 29 strains of penicillin-resistant S. pneumoniae (PRSP), 30 strains of Pseudomonas aeruginosa, 14 strains of Moraxella catarrhalis, and 25 strains of Haemophilus influenzae were examined. The minimum inhibitory concentration (MICs)50/90 (microg/ml) of imipenem, panipenem, meropenem, and biapenem against the clinical isolates obtained between 1999 and 2000 were: 0.06/0.25, 0.12/0.25, 0.12/0.25, and 0.12/0.25, respectively, against MSSA; 16/32, 16/32, 16/32, and 8/32 against MRSA; < or = 0.015/0.06, < or = 0.015/0.03, 0.03/0.12, and < or = 0.015/0.06 against PSSP; 0.12/0.25, 0.03/0.06, 0.25/0.5, and 0.12/0.25 against PRSP; 1/8, 2/8, 0.5/2, and 2/16 against P. aeruginosa; 0.06/0.06, 0.03/0.06, < or = 0.015/0.06, and 0.06/0.12 against M. catarrhalis; and 1/4, 1/4, 0.12/0.25, and 2/4 against H. influenzae. A comparison of the antibacterial activity of the four carbapenems with that found in our previous studies showed no significant difference in the susceptibility of clinical isolates, except for a slight decrease in the susceptibility of MSSA. Carbapenems have remained effective for severe infections. The MIC data showed that imipenem and panipenem were more active than meropenem and biapenem against gram-positive bacteria, and that meropenem and biapenem were more active than imipenem and panipenem against gram-negative bacteria. As only meropenem had an MIC90 below the breakpoint of pneumonia against all species except MRSA, meropenem was considered to be the most potent of the four carbapenems studied.

Anti-Bacterial Agents↗
PubMed2001

Production of monoclonal antibodies against mammalian Ring1B proteins.

The Polycomb group (PcG) genes play a role of transcriptional repressor for long-term maintenance of the Hox cluster gene expression. Recently two structurally similar gene products, Ring1A and Ring1B, were identified. Genetic evidence has indicated that Ring1A has Pc-G properties, however, Ring1B functions are still unknown. To gain functional insights for Ring1B, we raised the mouse monoclonal antibodies (MAbs) against murine Ring1B protein. Using these antibodies, we have detected specifically mouse, human and monkey Ring1B gene products from whole cell extracts in immunoblot and immunoprecipitation analyses. Immunofluorescent staining by the antibodies has shown that endogenous Ring1B proteins clearly co-localize with Ring1A at the pattern of diffuse nuclear speckles. Together with their sequence similarity, Ring1B also may function as a Pc-G protein. Finally, we have proposed that the anti-Ring1B would be useful for biochemical and cytological analyses of Ring1B and Pc-G complex.

Animals↗
PubMed2001

Leupeptin-induced appearance of partial fragment of betaine homocysteine methyltransferase during autophagic maturation in rat hepatocytes.

A cytosolic enzyme, betaine homocysteine methyltransferase (BHMT), and its partial fragments were discovered as autolysosomal membrane proteins from rat liver in the presence of leupeptin [Ueno et al. (1999) J. Biol. Chem. 274, 15222-15229]. The present study was undertaken to further characterize the transport and processing of BHMT from cytosol to autolysosome and to test if the fragment can be used as an in vitro probe for the maturation step of macroautophagy. Upon subcellular fractionation, BHMT (p44) was found in all fractions, while its 32-kDa fragment (p32) was found only in the mitochondrial-lysosomal (ML) fraction. Incubation of isolated hepatocytes with leupeptin induced time-dependent accumulation of p32 in the ML fraction from 30 to 90 min after the start of incubation. However, chloroquine completely inhibited the appearance of p32, indicating that the processing from p44 to p32 is lysosomal. Incubation with Bafilomycin A(1), a vacuolar H(+)-ATPase inhibitor, together with leupeptin, led to linear accumulation of p44, but not of p32. The p44 accumulation rate was calculated to be 4.9%/h, which was comparable to autophagic sequestration rate. The distribution of p44 within the ML fraction turned out to be dual, i.e., the membrane-surface attached and luminal/sedimentable forms. Amino acids and 3-methyladenine, both of which specifically suppress macroautophagy, inhibited the accumulation of p32 as well as of p44. Finally, energy-dependent appearance of p32 was demonstrated during incubation of postnucler supernatant fractions, making it possible to establish an in vitro assay system. All the results strongly support the idea that BHMT is taken up and degraded to p32 through the macroautophagic pathway, and that p32 could be a novel probe for the maturation of macroautophagy.

Animals↗
PubMed2001

Generation of oxidative stress contributes to the development of pulmonary hypertension induced by hypoxia.

Chronic hypoxia causes pulmonary hypertension and right ventricular hypertrophy associated with pulmonary vascular remodeling. Because hypoxia might promote generation of oxidative stress in vivo, we hypothesized that oxidative stress may play a role in the hypoxia-induced cardiopulmonary changes and examined the effect of treatment with the antioxidant N-acetylcysteine (NAC) in rats. NAC reduced hypoxia-induced cardiopulmonary alterations at 3 wk of hypoxia. Lung phosphatidylcholine hydroperoxide (PCOOH) increased at days 1 and 7 of the hypoxic exposure, and NAC attenuated the increase in lung PCOOH. Lung xanthine oxidase (XO) activity was elevated from day 1 through day 21, especially during the initial 3 days of the hypoxic exposure. The XO inhibitor allopurinol significantly inhibited the hypoxia-induced increase in lung PCOOH and pulmonary hypertension, and allopurinol treatment only for the initial 3 days also reduced the hypoxia-induced right ventricular hypertrophy and pulmonary vascular thickening. These results suggest that oxidative stress produced by activated XO in the induction phase of hypoxic exposure contributes to the development of chronic hypoxic pulmonary hypertension.

Acetylcysteine↗
PubMed2001

Endothelin receptor antagonist prevents parathyroid cell proliferation of low calcium diet-induced hyperparathyroidism in rats.

Secondary hyperparathyroidism, one of the most frequently encountered disorders of the calcium homeostasis, is characterized by an increase in parathyroid epithelial (PT) cell number, which is crucial from a functional viewpoint. However, it is still unknown what factors are involved in PT cell proliferation. Endothelin-1 (ET-1), a vasoconstrictive peptide, has been shown to act as a mitogen in a variety of cell types. Rat PT cells are reported to synthesize ET-1 and possess its receptors. To test the hypothesis that ET-1 plays a role in PT cell proliferation, we used rat test subjects fed a low calcium diet for 8 weeks (low Ca rats). The number of the proliferating PT cells, measured by proliferating cell nuclear antigen immunostaining, was significantly increased, with striking immunoreactivity of ET-1 in the low Ca rats. An endothelin receptor antagonist, bosentan (100 mg/kg.day), prevented any increase in the proliferation of PT cells in the low Ca rats (14.3 +/- 2.7/1000 PT cells with no bosentan; 2.1 +/- 1.3 with bosentan; P < 0.01). These results indicate that ET-1 is involved in PT cell proliferation in vivo and suggest that blocking of ET receptors may become one of the important therapeutic strategies for preventing secondary hyperparathyroidism.

Animals↗