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S Suzuki

Publications and source records attributed to S Suzuki.

At least 73 records · Page 4Linked to original sources
PubMed2004

A novel method for determination of ATP, ADP, and AMP contents of a single pancreatic islet before transplantation.

Assessment of islet viability before transplantation is mandatory for successful clinical transplantation. ATP content or energy charge (EC) of islets may represent a good parameter to assess viability. We have introduced a novel bioluminescent enzymatic cycling assay using synthetic firefly luciferase, pyruvate kinase) (PK), and pyruvate orthophosphate dikinase (PPDK) to determine adenine nucleotides (AN) in isolated islets. A complete assay requires several minutes. The ATP contents of 1, 3, 10, 30 or 100 islets each with a diameter of 150 microm were 9.95 +/- 0.03, 28.3 +/- 1.18, 89.5 +/- 1.48, 282 +/- 10.2, and 673 +/- 27.1 pmol, respectively, showing a relatively constant ATP content per 30 islets (9.95, 9.42, 8.95, and 9.41 pmol/IEQ). ECs of each group were 0.74 +/- 0.02, 0.74 +/- 0.02, 0.75 +/- 0.02, 0.74 +/- 0.02, and 0.65 +/- 0.01, respectively, a value that was quite constant up to 30 islets. The quantity of ATP and EC in a single islet can be measured quickly and reproducibly, offering a new method to determine viability of isolated islets prior to transplantation.

Adenosine Diphosphate↗
PubMed2004

Time course of gene expression after the injection of adenoviral vectors containing CTLA4IG gene.

INTRODUCTION: In vivo gene transfection using a recombinant adenoviral vector leads to diminished gene expression in a time-dependent manner that disappears within 4 weeks. CTLA4Ig blocks CD28-mediated costimulatory signal, and inhibits immune responses. We investigated the duration of transgene expression after administration of adenoviral vector containing CTLA4Ig gene (AdCTLA4Ig). METHODS: We injected 1 x 10(9) plaque forming units (pfu) of AdCTLA4Ig into rats (n = 7) via the tail vein. Thereafter, the blood samples were collected for assay of serum CTLA4Ig levels using enzyme-linked immunosorbent assay. RESULTS: The CTLA4Ig level reached the maximum (range, 65-86 microg/mL; average, 75 microg/mL) on days 3 to 5 after injection. Detectable levels of CTLA4Ig were observed up to 49 days. When we injected AdCTLA4Ig in combination with FTY720 administration, the maximum levels were higher and the detectable levels persisted longer. CONCLUSIONS: Because directly injected adenoviral transgene expression had been reported to disappear between 21 to 30 days, we conclude that AdCTLA4Ig inhibits the immune response and prolongs the transgene (CTLA4Ig gene) expression. Some additional immunosuppressants, like FTY720, may be useful to enhance AdCTLA4Ig effects.

Abatacept↗
PubMed2004

Salmonella Enteritidis outbreak associated with a school-lunch dessert: cross-contamination and a long incubation period, Japan, 2001.

A Salmonella Enteritidis (SE) outbreak in Japan was investigated with an observational study, analytical epidemiology and bacteriological examination (including phage typing). The outbreak occurred among 96 schoolchildren, and was caused by SE phage type 1. The outbreak source was dessert buns served at a school lunch (RR 42.55, 95 % CI 5.93-305.11, P < 0.001). The buns were probably cross-contaminated from eggs from a factory with a history of SE-contaminated products. The incubation period was longer than usual (3-16 days, median 8 days). A low contaminating dose may account for the long incubation period and low attack rate. Outbreak detection was hampered by the absence of routine Salmonella surveillance in Japan. The investigation was complicated by concurrent illnesses from other SE phage types. It was successful, in part, because adequate food samples were available for microbiological testing.

Child↗
PubMed2004

Photodynamic therapy for malignant biliary obstruction: a case series.

We describe four elderly patients (age range 73-85 years) with bile duct carcinoma who were treated with photodynamic therapy. These patients could not be treated surgically because of the presence of cardiopulmonary disease and the extent of the bile duct carcinoma. Prior to photodynamic treatment the patients underwent percutaneous transhepatic biliary drainage (PTBD) to relieve jaundice. The photodynamic therapy was carried out under percutaneous transhepatic cholangioscopy, 2 days after intravenous administration of sodium porfimer (2 mg/kg). Excimer dye laser was used to irradiate the obstructive lesion with an energy dosage of 50 J/cm2 (total irradiation dose 150-250 J/cm2) and stenotic site with a dosage of 50-100 J/cm2. Photodynamic therapy was achieved safely without occurrence of cholangitis in all patients, and was followed by metallic stent placement, resulting in the improvement of performance levels in three patients who did not have liver metastases. Photodynamic therapy via the PTBD route is a safe and promising palliative therapy for selected elderly patients with bile duct carcinoma.

Aged↗
PubMed2004

Use of intraoperative dynamic infrared imaging with detection wavelength of 7-14 microm in the surgical obliteration of spinal arteriovenous fistula: case report and technical considerations.

BACKGROUND AND OBJECTIVE: Although improvements of spatial and temporal resolution in infrared (IR) imaging have enabled intraoperative real-time acquisition of physiological and pathological information on living organs, the imaging qualities of anatomical delineation of blood vessels and functional delineation of blood flow were insufficient to serve as visual monitoring. The main reason was partly due to the lack of an appropriate IR detection IR band (formerly 3 - 5 micro m), and the broad dynamic range in previous modalities. METHODS: To make a good contrast between blood vessels and surrounding tissues, the detection wavelength was shifted to the long-wave (7 - 14 micro m) part of IR spectrum, which includes the peak IR wave from living tissue (9 - 10 micro m), and the dynamic range was confined to +/- 10 degrees C around 35 degrees C. The novel camera system (IRIS IV infrared imaging system) was used for the visual monitoring of blood flow during the obliteration of a spinal perimedullary arteriovenous fistula at Th 7 in 71-year-old male patient. The temperature resolution of camera was 0.15 degrees C, with its intensity resolution of 16 bit (320 x 240 pixels), and data were stored at a rate of 30 frames/second. High-quality delineation of blood vessels and blood flow was obtained all through the procedure without use of cold saline, which was an inevitable procedure to make contrast in the previously used thermography. However, the occasional use of an air blower was helpful to achieve adequate images in the deep and narrow area of the surgical field. The amount of shunt flow reduction was visualized by the intensity in the acquired imaging, which was also confirmed later by digital subtraction angiography. CONCLUSION: From the present experience, it is considered that this type of imaging may be able to substitute intraoperative blood vessel and blood flow monitoring in spinal and other neurosurgical disorders.

Aged↗
PubMed2004

Influence of the duration of the second stage of labor on fetal pH levels and oxidative status in uncomplicated pregnancies.

OBJECTIVE: We examined the influence of the duration of the second stage of labor on fetal pH levels and oxidative status in uncomplicated pregnancies. METHODS: Blood gases in the umbilical artery and serum uric acid and plasma malondialdehyde levels in the umbilical venous blood were measured at delivery in uncomplicated nulliparous women whose second stage of labor was 0-60 min (n = 38), 61-120 min (n = 14) and 121-180 min (n = 6). RESULTS: There were no significant differences in the measured variables between the three groups. CONCLUSION: The duration of the second stage of labor up to 3 h does not influence lipid peroxidation in the fetoplacental circulation in uncomplicated pregnancies.

Adult↗
PubMed2004

Double-stranded RNA activates RANTES gene transcription through co-operation of nuclear factor-kappaB and interferon regulatory factors in human airway epithelial cells.

BACKGROUND: Regulated on activation, normal T cells expressed and secreted (RANTES) is a member of the CC chemokine family and contributes to viral-induced airway inflammation including exacerbations of asthma. Double-stranded RNA (dsRNA) is known to be synthesized during replication of many viruses and a ligand of Toll-like receptor 3. We hypothesized that dsRNA may mimic viral infection and induce RANTES expression in airway epithelial cells. OBJECTIVE: We first confirmed that dsRNA up-regulated RANTES mRNA and protein synthesis in the airway epithelial cells. We next focused our studies on the transcriptional regulation of RANTES. METHODS: Airway epithelial cell line BEAS-2B and normal human bronchial epithelial cells were used in vitro study. Levels of RANTES mRNA and protein expression were determined with RT-PCR and ELISA. Mechanisms of transcriptional regulation were assessed by electrophoretic mobility shift assay and dual luciferase assay using RANTES promoter-luciferase reporter plasmids. RESULTS: Activation of nuclear factor-kappaB (NF-kappaB) was confirmed by nuclear protein binding to a DNA probe derived from the RANTES promoter. Activity of the RANTES promoter was increased by dsRNA. The stimulation with dsRNA was partially inhibited in plasmids mutated at either of the binding sites for NF-kappaB or IFN regulatory factors (IRFs). When both sites were mutated, the activation was totally abrogated. CONCLUSION: These results imply that dsRNA activates NF-kappaB and IRFs and these transcription factors activate transcription of the RANTES promoter and its protein expression in airway epithelial cells.

Bronchi↗
PubMed2004

Intraosseous benign notochordal cell tumours: overlooked precursors of classic chordomas?

AIMS: Intraosseous benign notochordal cell tumour is a recently recognized condition that may undergo malignant transformation to classic chordoma. The aim of this study was to describe its clinicopathological characteristics. METHODS AND RESULTS: One hundred vertebral columns from atlas to coccyx and 61 pieces of the clival portion of the skull base, which were dissected from 100 autopsy cases, were examined microscopically. Twenty-six intraosseous benign notochordal cell tumours were found in 20 cases. The patient group consisted of 15 males and five females with a mean age of 63 years. The results, according to anatomical segments, showed that 11.5% of the clivus, 5.0% of the cervical vertebrae, 0% of the thoracic vertebrae, 2.0% of the lumbar vertebrae, and 12.0% of the sacro-coccygeal vertebrae were affected. Microscopic examination revealed well demarcated but unencapsulated sheets of bland physaliphorous cells mimicking adipocytes. The lesions lacked any intercellular myxoid matrix. The affected bone trabeculae were characteristically sclerotic. CONCLUSIONS: The study indicated a surprisingly high incidence of intraosseous benign notochordal cell tumours. The anatomical distribution of the tumours was identical to that of classic chordomas. The results support other evidence that classic chordomas develop from intraosseous benign notochordal cell tumours.

Age Factors↗
PubMed2004

Distribution of marine birnavirus in cultured marine fish species from Kagawa Prefecture, Japan.

To determine the distribution of marine birnavirus (MABV) in cultured populations of different marine fish species, 1291 pooled tissue samples from 2672 fish belonging to 22 species and one hybrid were collected from Kagawa Prefecture, Japan, during 1999-2001. Using cell-culture MABV was isolated from three species: yellowtail, Seriola quinqueradiata Temminck & Schlegel (positive number/sample number, 10/419), amberjack, S. dumerili (Risso) (4/72), and Japanese flounder, Paralichthys olivaceus (Temminck & Schlegel) (41/481). Using PCR on MABV-negative samples, the MABV genome was detected in the same three species [yellowtail (9/409), amberjack (4/68) and Japanese flounder (93/440)] and two additional species, spotted halibut, Verasper variegatus (Temminck & Schlegel) (5/11), and goldstriped amberjack, S. lalandi Valenciennes (1/5). These MABV-positive species can be taxonomically divided into two groups: the genus Seriola and flatfish. In Japanese flounder, MABV was detected during all seasons, and the infection rate was correlated with water temperature. Aquaculture sites with MABV-positive fish were evenly distributed over the surveyed area, suggesting that MABV is widely distributed at aquaculture sites in Kagawa Prefecture. The nucleotide sequence at the variable region, the VP2/NS junction, revealed that the 39th base mutation occurs host-specifically for flatfish. Flatfish are suspected to be the main reservoir of MABV and might be responsible for establishing the infection cycle in aquaculture environments.

Animals↗
PubMed2004

Aquabirnaviruses isolated from marine organisms form a distinct genogroup from other aquabirnaviruses.

A phylogenetic tree of aquabirnaviruses, including marine birnaviruses (MABV) and infectious pancreatic necrosis virus (IPNV), was developed based on the nucleotide sequences and deduced amino acid sequences of the polyprotein and VP5 genes of genomic segment A. In the polyprotein of MABV strains, the amino acid sequences were very similar, with identities of 98.3-99.7%. Twenty-one unique amino acid residues were found in the deduced amino acid sequences of the polyprotein gene of MABV strains. The phylogenetic tree based on the nucleotide sequence of genomic segment A and polyprotein sequences showed that 31 aquabirnavirus strains were clustered into seven genogroups. All MABV strains isolated in Japan and Korea were clustered into one genogroup which was distinct from other aquabirnaviruses. The seventh genogroup containing all MABV strains showed amino acid sequence similarities of 80.7-90.6% with other genogroups. In VP5, four unique residues were found in MABV strains when compared with IPNV strains. The MABV strains exhibited amino acid sequence similarities of 63.9-86.4% with IPNV strains. The amino acid sequences of VP5 were conserved among MABV strains, but differed from those of IPNV strains. The MABV strains isolated from different host species and different geographical areas were very similar to each other, suggesting that the MABV are distinct from the other genogroups.

Amino Acid Sequence↗
PubMed2004

Promoter polymorphism of SLC11A1 (formerly NRAMP1) confers susceptibility to autoimmune type 1 diabetes mellitus in Japanese.

Defective function of antigen-presenting cells has been postulated to be one of the non-HLA-linked susceptibility factors for type 1 diabetes mellitus, though the underlying genetic factors remain unclear. SLC11A1 (formerly NRAMP1), a divalent cation transporter, plays a crucial role in macrophage activation. We performed a case-control study in 224 healthy and 95 type 1 diabetic Japanese subjects, examining the length polymorphisms in the promoter region (-377 to -222) of SLC11A1, which may influence transcriptional activity. Alleles designated 2, 3, and 7 have been identified in Japanese subjects. The frequency of allele 7 was significantly higher in subjects with type 1 diabetes (9.47%) than in the healthy controls (4.46%). The difference is more marked in the subpopulation of Japanese subjects with type 1 diabetes; diabetic subjects with at least one protective HLA class II allele and those without any susceptibility HLA class II haplotypes, DR4-DQ4 or DR9-DQ9, had a much higher allele 7 frequency than controls. These findings suggest that the novel promoter polymorphism of SLC11A1 influences the susceptibility to type 1 diabetes in Japanese subjects.

Adolescent↗
PubMed2004

Effects of antiplatelet agents on pulmonary haemodynamic response to fMLP in endotoxin primed rats.

BACKGROUND: The interaction between neutrophils and platelets may be important in the modulation of pulmonary haemodynamics under systemic inflammatory conditions. A study was undertaken to examine whether antiplatelet agents inhibit platelet-neutrophil adherence and ameliorate the pulmonary haemodynamic response to fMLP by inhibiting thromboxane release in endotoxin primed lungs. fMLP stimulates neutrophils but not platelets; however, thromboxane synthesis in neutrophils is very low. METHODS: Rats were pretreated with either cilostazol (300 mg/kg) or aspirin (50 mg/kg) before endotoxin priming (5 mg/kg). Platelets in the lung were identified by fluorescent immunohistochemistry. Platelet-neutrophil adherence was analysed by flow cytometry of the lung vascular flush. The effect of fMLP (10(-6) M) on thromboxane release, lung weight (an indicator of pulmonary vasoconstriction), and lung filtration coefficient was determined in an isolated lung system perfused at a constant pressure difference. RESULTS: Endotoxin induced platelet accumulation and platelet-neutrophil adherence in the lung capillary were completely inhibited by cilostazol and aspirin while neutrophil recruitment was not affected. The fMLP challenge caused a significant increase in thromboxane B2 levels in endotoxin primed lungs. The fMLP induced decrease in lung weight was enhanced by endotoxin priming (from -4.9 to -63.9 mg, 95% CI of mean difference -99.5 to -10.5 mg, p<0.05). The fMLP induced increase in the lung filtration coefficient was also enhanced by endotoxin priming (from 0.63 to 2.40 mg/min/cm H2O/g, 95% CI of mean difference 1.17 to 2.37 mg/min/cm H2O/g, p<0.05). Treatment with cilostazol and aspirin completely inhibited the enhanced pulmonary haemodynamic response to fMLP. CONCLUSION: The neutrophil-platelet interaction is of critical importance in the modulation of pulmonary haemodynamics via thromboxane.

Animals↗
PubMed2004

Local administration of IGF-I stimulates the growth of mandibular condyle in mature rats.

AIM: To evaluate the effects of local injection of insulin-like growth factor I (IGF-I) on the growth of mandibular condyle in mature rats. MATERIALS AND METHODS: Sixteen 15 week-old male rats were used in this study. In the experimental group, IGF-I at a concentration of 50 microg/ml was injected into articular capsules of the condyle, while rats in the control group were injected with equal volume of physiological saline. These injections were performed three times at 7 day intervals, and all of the rats were killed on the 7th day after the last injection. Tetracycline and calcein were used for vital staining. After death, the condyles were extracted and undecalcified ground sections were prepared for histological and histomorphometric observations. The thickness of the cartilaginous layer of the condyle, the percentage of bone area in the subchondral cancellous bone layer and the amount of endochondral bone growth in the condyle were measured. The significance of the difference in these measurements between IGF-I and control group was evaluated. RESULTS: An increase in the thickness of the cartilaginous layer, and a decrease in the percentage of bone area in the subchondral cancellous bone layer was recognized in IGF-I treated condyle. The amount of endochondral bone growth in the experimental group was greater than that in the control group. CONCLUSION: The local injection of IGF-I into mature condyle seemed to reactivate the process of endochondral bone formation and induced actual bone growth in mature condyle.

Animals↗
PubMed2004

Comparisons of LET distributions for protons with energies between 50 and 200 MeV determined using a spherical tissue-equivalent proportional counter (TEPC) and a position-sensitive silicon spectrometer (RRMD-III).

Experiments have been performed to measure the response of a spherical tissue-equivalent proportional counter (TEPC) and a silicon-based LET spectrometer (RRMD-III) to protons with energies ranging from 50-200 MeV. This represents a large portion of the energy distribution for trapped protons encountered by astronauts in low-Earth orbit. The beam energies were obtained using plastic polycarbonate degraders with a monoenergetic beam that was extracted from a proton synchrotron. The LET spectrometer provided excellent agreement with the expected LET distribution emerging from the energy degraders. The TEPC cannot measure the LET distribution directly. However, the frequency mean value of lineal energy, y(-)(f), provided a good approximation to LET. This is in contrast to previous results for high-energy heavy ions where y(-)(f) underestimated LET, whereas the dose-averaged lineal energy, y(-)(D), provided a good approximation to LET.

Linear Energy Transfer↗
PubMed2004

Relationship of plasma extracellular-superoxide dismutase level with insulin resistance in type 2 diabetic patients.

Extracellular-superoxide dismutase (EC-SOD) is a secretory glycoprotein located in blood vessel walls at high levels and may be important in the antioxidant capability of vascular walls. The aim of this study was to assess plasma levels of EC-SOD and to evaluate the relationship of the EC-SOD level with insulin resistance in type 2 diabetic patients. We determined plasma EC-SOD in 122 patients and found for the first time that the EC-SOD level was strongly and positively related to adiponectin (r=0.503, P < 0.001), and significantly and inversely related to fasting plasma glucose (FPG) (r=-0.209, P=0.022), body-mass index (BMI) (r=-0.187, P=0.040) and homeostasis model assessment-insulin resistance index (HOMA-R) (r=-0.190, P=0.039). Stepwise-multiple regression analysis also showed a significant influence of adiponectin (F=33.27) on the EC-SOD level. Administration of pioglitazone to 19 diabetic patients significantly increased the plasma levels of EC-SOD (69.9+/-19.3 ng/ml to 97.4+/-25.9 ng/ml; P < 0.0001) and adiponectin, while it decreased tumor necrosis factor-alpha (TNF-alpha). The present observations suggest that factors related to the pathogenesis of insulin resistance play an important role in the regulation of the plasma EC-SOD concentration. It is possible that the increase in the EC-SOD level by pioglitazone administration in diabetic patients is due to a decline of TNF-alpha, which is known to suppress EC-SOD expression.

Adiponectin↗