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S Watanabe

Publications and source records attributed to S Watanabe.

At least 415 records · Page 23Linked to original sources
PubMed2000

A case of ileocolic intussusception from renal cell carcinoma.

We report a case of ileal metastasis of renal cell carcinoma (RCC) in a 58-year-old male. The patient had a history of radical nephrectomy for a right RCC, and 2 years later underwent bilateral partial pneumonectomy for metastatic disease of the lung. A period of 1 year after the partial pneumonectomy, he developed bloody stools. Colonoscopy revealed an ileocolic intussusception caused by a polypoid tumor in the ileum, and the tumor was observed to be protruding into the ascending colon. The histological features of the tumor biopsy specimen confirmed the diagnosis of metastatic RCC. Metastasis of RCC in the small bowel is a rare disease clinically. To our knowledge, this is the first reported case with ileal metastasis of RCC, which has been definitively diagnosed by colonoscopy.

Biopsy↗
PubMed2000

Volume measurement using tissue characterization of three-dimensional endoscopic ultrasonographic images.

BACKGROUND AND STUDY AIMS: Although it is time-consuming to measure the volume of lesions using three-dimensional endoscopic ultrasonography (3D-EUS), the technique is suitable for tissue characterization, as it allows images of multiple areas to be obtained simultaneously in uniform conditions. The present study tested automatic volume measurement using tissue characterization based on 3D-EUS. MATERIALS AND METHODS: Nine polygonal sections of resected spleen (volume 0.66 +/- 0.19 cm3) were immersed in water, and 40 radial 3D-EUS images were obtained. For tissue characterization, the methods of co-occurrence matrix and gray-level difference and discriminant analysis were used. Each spleen section was also measured using 3D-EUS. The volume of tissue identified as spleen using tissue characterization and the volume calculated on the basis of the 3D-EUS images were both compared with the actual volume measured beforehand. Measurements using tissue characterization and 3D-EUS were carried out for every third image. In three clinical cases of cancer the volume of the lesion was measured using tissue characterization and 3D-EUS. RESULTS: The mean volume of the nine splenic sections estimated using tissue characterization was 1.2 +/- 0.41 cm3 (mean +/- SD), while the mean volume estimated with 3D-EUS imaging was 1.1 +/- 0.30 cm3 (mean +/- SD). The volumes measured using tissue characterization were on average 13% larger than those obtained with 3D-EUS. Linear regression analysis showed a high degree of correlation between the two sets of measurements (r=0.97, P<0.00005), and also showed a high correlation between the volumes obtained using tissue characterization and the actual volume (r=0.93, P<0.0005). However, the volumes calculated using 3D-EUS images were larger than the actual volume (61% on average), and the volumes estimated using tissue characterization were also greater than the actual volume. The overestimation reflected the fact that measurement was only carried out in every third 3D-EUS image. In the clinical cases, the mean value for "true" tumor tissue as determined on EUS imaging represented 73% of the volume interpreted as cancer using tissue characterization. CONCLUSIONS: There was a good correlation between the volume measured with 3D-EUS and the volume obtained using tissue characterization. The tissue characterization volumes were only relatively slightly larger than the volumes measured using 3D-EUS, suggesting that there may be some promise for this application of tissue characterization.

Aged↗
PubMed2000

Ganglioside GQ1b enhances anti-double-stranded DNA antibody and IgG production of PBMCs from patients with systemic lupus erythematosus.

BACKGROUND: Previously, we reported that ganglioside GQ1b greatly enhanced spontaneous immunoglobulin production in vitro by PBMCs from normal human subjects. OBJECTIVE: We examined in vitro effects of GQ1b on anti-double-stranded DNA (anti-dsDNA) antibody production by PBMCs from patients with systemic lupus erythematosus (SLE). METHODS: PBMCs from patients with SLE were cultured with GQ1b. IgG anti-dsDNA antibody, total IgG, and cytokine amounts in the culture supernatants and protein kinase C (PKC) activity of T cells were measured by using ELISA. RESULTS: GQ1b enhanced both anti-dsDNA and total IgG production of PBMCs from patients with SLE who were seropositive for anti-dsDNA. Among the seropositive patients, the active patients were more responsive to GQ1b in anti-dsDNA production than the inactive patients. GQ1b also enhanced total IgG production of PBMCs from patients with SLE who were seronegative for anti-dsDNA but did not induce their anti-dsDNA production. In contrast to PBMCs, GQ1b did not affect the antibody production either of purified CD5(+) or of CD5(-) B cells. Anti-IL-6 or anti-IL-10 antibody each partially blocked the GQ1b-induced enhancement of antibody production in PBMCs, and the addition of both antibodies completely blocked the enhancement. GQ1b increased IL-6 and IL-10 production of T cells. The supernatant from GQ1b-treated T cells enhanced antibody production both of CD5(+) and of CD5(-) B cells to a greater extent than that from medium-treated T cells. Exogenous IL-6 and IL-10 additively increased the antibody production both of CD5(+) and CD5(-) B cells. GQ1b-induced increases in IL-6 and IL-10 production of T cells were both blocked by PKC inhibitors, calphostin C and staurosporine. GQ1b enhanced PKC activity of T cells. CONCLUSION: These results suggest that GQ1b may polyclonally increase the production of IgG, including IgG anti-dsDNA antibody, in PBMCs from patients with SLE by promoting IL-6 and IL-10 production of T cells through the enhancement of their PKC activity.

Adjuvants, Immunologic↗
PubMed2000

Analysis of antiapoptosis activity of human GM-CSF receptor.

Human GM-CSF (hGM-CSF) induces proliferation and sustains the viability of a mouse IL-3-dependent lymphoid cell line BA/F3 that expresses the functional hGM-CSF receptor (hGMR). To reveal an antiapoptotic mechanism of hGM-CSF, we analyzed various apoptotic markers of BA/F3 cells in various conditions. Within 24 hours of factor depletion, caspase 3-like, but not caspase 1-like, enzyme activity and DNA fragmentation were augmented. Analysis with the tyrosine kinase inhibitor (genistein) and an MEK1 inhibitor (PD98059) on antiapoptosis activity indicates that the activation of either the genistein-sensitive signaling pathway or the PD98059-sensitive signaling pathway of the betac subunit may be sufficient to suppress apoptosis through hGMR. Because hGMR mutants (which activate JAK2 but neither STAT5 nor the MAPK cascade) have antiapoptotic activity in BA/F3 cells, the involvement of JAK2, excluding the molecules mentioned earlier, for antiapoptosis activity seems likely. Because the JAK2 inhibitor AG-490 suppressed the antiapoptotic activity of hGM-CSF, the essential role for JAK2 activation to maintain the viability is considered. Interestingly, hGMR mutants, which lack MAPK cascade activation, require a higher dose of hGM-CSF than that for wild-type hGMR. Because the expression level and affinity to hGM-CSF among wild-type hGMR and mutant hGMR are the same, we speculated that biologic response is determined by a combination of strength of various signaling events.

Apoptosis↗
PubMed2000

Seasonal changes in calcium homeostasis affect the incidence of postoperative tetany in patients with Graves' disease.

BACKGROUND: We have found that postoperative tetany occurs in patients with Graves' disease who have secondary hyperparathyroidism caused by a deficiency in calcium and vitamin D concomitant with transient hypoparathyroidism after surgery. There are seasonal variations in serum 25-hydroxyvitamin D (25[OH]D) concentrations. The purpose of this study was to investigate the effects of seasonal changes in calcium homeostasis on the incidence of postoperative tetany in patients with Graves' disease who undergo subtotal thyroidectomy. PATIENTS AND METHODS: A prospective study was carried out to investigate sequential changes in serum levels of intact parathyroid hormone (iPTH), calcium and other electrolytes, 25(OH)D, and 1,25-dihydroxyvitamin D (1,25[OH]2D) in female patients with Graves' disease who underwent subtotal thyroidectomy during the summer (n = 89) and during the winter (n = 89). RESULTS: The serum levels of calcium, magnesium, and 25(OH)D were significantly higher, but iPTH levels and 1,25(OH)2D levels were lower in summer than in winter. The percentage of vitamin D deficiency (25(OH)D < 25 nmol/L) was 23% in summer and 62% in winter (P < .001). iPTH was below the detection limit on the first postoperative day in 15 patients (13.8%) in summer and in 13 patients (11.4%) in winter. In summery, tetany developed in only 4 of 15 patients and in one patient whose iPTH level was below normal (incidence of tetany, 5.6%). In winter, however, tetany developed in 6 of 13 patients and in 4 patients whose iPTH level was below normal (incidence of tetany, 11.2%). CONCLUSIONS: Patients with Graves' disease are more susceptible to calcium and vitamin D deficiency during the winter than during the summer, resulting in the tendency toward a higher incidence of postoperative tetany in winter.

Adult↗
PubMed2000

The influence of human T lymphotropic virus type I infection on the outcome of cardiovascular surgery.

OBJECTIVE: Human T lymphotropic virus type I infects CD4(+) T cells and affects cell-mediated immunity. Cardiopulmonary bypass transiently alters lymphocyte subsets, resulting in a reduction in CD4(+) T cells and an increase in CD8(+) T cells. We proposed that cardiovascular operations and human T lymphotropic virus type I infection may act synergistically, resulting in serious damage to cell-mediated immunity. METHODS: A total of 517 consecutive patients who were preoperatively screened for anti-human T lymphotropic virus type I antibody and underwent cardiovascular operations with cardiopulmonary bypass were enrolled in this study. Of the 517 patients, 82 (16%) had positive test results for anti-human T lymphotropic virus type I antibody. The surgical outcome of patients with positive and negative results for anti-human T lymphotropic virus type I antibody was analyzed retrospectively. RESULTS: There was no difference between the 2 groups with respect to early mortality. Distribution of survival curve was also not significantly different (P =.5; mean follow-up duration, 2.4 +/- 1.8 years [range, 0-9.4 years] and 3.2 +/- 2.8 years [range, 0-9.8 years]) in the groups with positive and negative antibody results, respectively). In particular, long-term follow-up did not reveal adult T-cell leukemia or human T lymphotropic virus type I-associated myelopathy, and occurrence of neoplasm did not differ between groups. Early infectious complication was, however, significantly higher in the group with positive antibody results than in the group with negative results (P =.02). Logistic regression analysis revealed human T lymphotropic virus type I infection as a significant risk for this complication (P =.04; odds ratio, 2.5; 95% confidence interval, 1. 0-5.8). CONCLUSION: A combination of human T lymphotropic virus type I infection and cardiovascular operation is believed to increase the potential risk of infectious complications shortly after the operation. However, this synergistic effect seems to be transient and has little influence on long-term prognosis.

Aged↗
PubMed2000

Preoperative autologous donation of blood for a simple cardiac anomaly: analysis of children weighing under twenty kilograms.

OBJECTIVE: Preoperative autologous donation of blood has been expanded to cardiac operations in children. However, because of problems such as lack of cooperation and hemodilution during cardiopulmonary bypass, its efficacy in small children is unclear. This study clarifies the clinical significance of preoperative autologous donation of blood in small children. METHODS: Thirty-seven patients weighing under 20 kg (age range, 3-9 years; weight range, 13-20 kg) underwent preoperative autologous donation and cardiac operations to treat a simple anomaly. Twenty-five age- and weight-matched patients who were not cooperative or refused preoperative autologous donation served as control subjects. Autologous blood was collected by the simple or leapfrog method and stored as blood components. Each collecting volume was 5 to 10 mL/kg. RESULTS: The donation was performed 6+/-2 times during 50+/-16 days, and the whole storage volume was 48+/-17 mL/kg. There was no serious complication. The minimum hematocrit level negatively correlated with the priming volume of cardiopulmonary bypass (preoperative donation patients: P<.01, r(2) = 0.4; control subjects: P =.5, r (2) = 0.03). Blood loss did not significantly differ between preoperative donation patients and control subjects, and the transfused blood volumes were 43+/-13 mL/kg and 29+/-22 mL/kg, respectively. All of the autologous blood products but fresh frozen plasma were reinfused. Use of homologous blood was significantly less in preoperative donation patients than in control subjects (0% vs 80%, P <.01). In preoperative donation patients postoperative recovery in hemoglobin level was significantly better, which is concurrent with a higher reticulocyte level. CONCLUSION: Preoperative autologous donation can be performed safely with clinical efficacy, even in children under 20 kg. This can be improved further through coupling with another procedure.

Analysis of Variance↗
PubMed2000

Presence of bacterial 16S ribosomal RNA gene segments in human intestinal lymph follicles.

BACKGROUND: There is currently no information regarding microbial agents inside the intestinal lymph follicles. METHODS: Biopsy or resected specimens, mostly from macroscopically normal areas, were sectioned with a cryostat. DNA was extracted from microdissected samples, exclusively from the lymph follicle. Amplification of DNA was performed using universal primers designed from conserved regions of bacterial 16S ribosomal RNA (rRNA). Several clones with inserts of around 400 base pairs were subjected to DNA sequence analysis followed by a database homology search. RESULTS: Bacterial 16S rRNA gene segments were detected in the lymph follicle in 2 of 14 (14%) non-inflammatory bowel disease (IBD) cases, 4 of 14 (28%) Crohn disease cases, and in 2 of 5 (40%) ulcerative colitis cases. Nineteen 16S rRNA gene segments were recognized in the eight positive cases. Five segments showed 100% identity to known bacterial 16S rRNAs, namely staphylococcus species, Streptococcus sanguis, and Paracoccus marcusii. However, the other 14 segments showed below 100% identity, indicating either the presence of unknown bacteria or of bacteria without known DNA data. No single identified or unidentified bacterium, characteristic of IBD, including Mycobacterium paratuberculosis and Listeria monocytogenes, was detected. CONCLUSIONS: The present study confirms the presence of bacterial 16S rRNA gene segments in human intestinal lymph follicles and paves the way for new investigations into the microbiology of the lymph follicle. Whether or not bacteria inside the lymph follicle is a primary stimulus in IBD has yet to be clarified.

Adolescent↗
PubMed2000

Calcium and its regulating hormones in patients with graves disease: sex differences and relation to postoperative tetany.

OBJECTIVE: To find out why female sex is the most important risk factor for tetany, as calcium and bone metabolism may differ between the sexes. DESIGN: Prospective study. SETTING: Thyroid centre, Japan. PATIENTS AND METHODS: 45 men (mean age 35 years, SD 13) and 178 women (mean age 33 years, SD 12) with Graves disease treated by subtotal thyroidectomy. INTERVENTIONS: Measurement of serum concentrations of intact parathyroid hormone (iPTH), calcium, electrolytes, 25-hydroxyvitamin D (25 (OH) D), and 1,25-dihydroxyvitamin D (1,25 (OH) 2D). MAIN OUTCOME MEASURES: Mean values of these substances, together with reductions in serum calcium concentration, relative youth, increased alkaline phosphatase activity, large goitre, and increased serum TSH binding inhibitory globulin concentration. RESULTS: Women had significantly lower calcium concentrations than men (mean (SD) 2.37 (0.13) compared with 2.43 (0.07), p = 0.003). Serum calcium concentrations correlated significantly with concentrations of 25 (OH) D (p < 0.001). 121 of the women (68%) compared with 13 (29%) of men had vitamin D deficiency as defined as 25 (OH) D < 25 nmol/l (p < 0.05). 15 patients (8%) developed tetany postoperatively compared with I man (2%, p = 0.2). CONCLUSION: Women with Graves disease are more susceptible to calcium and vitamin D deficiency than men, which may account for the higher incidence of postoperative tetany among women with the disease.

25-Hydroxyvitamin D 2↗
PubMed2000

Differences among chitin synthase I gene sequences in Trichophyton rubrum and T. violaceum.

Nucleotide sequences of chitin synthase 1 (CHS1) gene were analysed for the phylogenetic relation between Trichophyton violaceum and T. rubrum, including two isolates of T. raubitschekii and one isolate of T. rubrum var. nigricans. About 620-bp genomic DNA fragments of the CHS1 gene were amplified from these dermatophytes by polymerase chain reaction (PCR) and sequenced. The CHS1 nucleotide sequences of these dermatophytes showed more than 95% similarity between the species. The phylogenetic analysis of their sequences revealed that T. rubrum was genetically distinct from T. violaceum. The specific restriction endonuclease site for HinfI was present in the CHS1 gene sequence of T. rubrum but not in that of T. violaceum. A molecular analysis of CHS1 genes will provide useful information for the identification of these Trichophyton species and the understanding of their evolution.

Animals↗
PubMed2000

Interaction of ubiquinone-10 with dipalmitoylphosphatidylcholine and their formation of small dispersed particles.

Stable aqueous dispersions of ubiquinone-10 (UQ) were obtained by cosonication with dipalmitoylphosphatidylcholine (DPPC) in the UQ mole fraction range 0.1-0.7. To clarify the dispersal mechanism, the dispersed particles were characterized, and the interaction between UQ and DPPC was investigated using several physicochemical techniques. Dynamic light scattering (DLS) measurements showed that the diameter of the dispersed particles was 50-70 nm. A limited amount of UQ was incorporated into DPPC bilayer membranes (approximately 5 mol%). The trapped aqueous volume inside the particles was determined fluorometrically using the aqueous space marker calcein, and the volume in the UQ/DPPC particles decreased remarkably with the addition of UQ into small unilamellar vesicles of DPPC. The decline in the fraction of vesicular particles was also confirmed by fluorescence quenching of N-dansylhexadecylamine in the DPPC membrane by the addition of the quencher CuSO4. These results indicate that the excess UQ separated from the DPPC bilayers is stabilized as emulsion particles by the DPPC surface monolayer.

1,2-Dipalmitoylphosphatidylcholine↗
PubMed2000

Comparison of the effect of lipid A analog E5531 and the lipid A from Escherichia coli on phospholipid membrane properties.

The effect of the lipid A analog E5531 on the phospholipid membrane was compared with that of the lipid A from Escherichia coli (EC). E5531 decreased the phase transition temperature of dipalmitoylphosphatidylcholine (DPPC) membrane and increased the fluidity and micropolarity. On the other hand, the effect of EC on the membrane was contradictory. These results suggested that the reason for the difference of biological effects of these two lipid A would be caused by the differences from the effect on the cell membranes.

Cell Membrane↗
PubMed2000

The effect of the membrane fluidity on pharmacokinetics for lipid A analog E5531.

The effect of the dispersing procedure on the aggregate size, membrane fluidity and the pharmacokinetics were evaluated for the lipid A analog E5531. The size of the aggregates prepared by the pH-jump method (pH 11.0-->7.3) was decreased, reaching 20 nm with increasing dispersing time in 0.003 N NaOH (pH 11.0). The membrane fluidity of the aggregates increased with increasing dispersing time. When prepared by the normal dilution method (pH 7.3-->7.3), the size of the aggregates remained constant at 150 nm and the membrane fluidity was smaller compared to samples prepared by the pH-jump method. Using samples with different degrees of hydration and different membrane fluidities prepared by the pH-jump method, the pharmacokinetics after intravenous administration into rats were evaluated, and the data obtained confirmed that the membrane fluidity was correlated with the pharmacokinetics in rat. In addition, E5531 vials were stable for 24 months at room temperature when used within 24 hr after reconstitution.

Animals↗
PubMed2000

The effect of lipid A analog E5531 on membrane properties of dipalmitoylphosphatidylcholine.

The effect of the lipid A analog E5531 on the phospholipid membrane was determined and compared with that of the lipid A from Escherichia coli (EC). E5531 decreased the phase transition temperature of dipalmitoylphosphatidylcholine (DPPC) membrane and increased the fluidity and permeability. On the other hand, EC increased the phase transition temperature and decreased the membrane fluidity and permeability. These results suggest that the reason for the difference of biological effects of E5531 and lipid A from EC would be caused by the differences from the effect on the cell membranes.

1,2-Dipalmitoylphosphatidylcholine↗
PubMed2000

Formation and stability of the dispersed particles composed of retinyl palmitate and phosphatidylcholine.

The purpose of this study was to develop an intravenous formulation composed of retinyl palmitate (RP) for the treatment of cancer. RP was dispersed with soybean phosphatidylcholine (PC) using sonication and the dispersal mechanism was evaluated by characterizing the dispersed particles using dynamic light-scattering, fluorescence spectroscopy, and surface monolayer techniques. The dispersions in the RP mole fraction range of 0.1-0.8 were stable at room temperature for 3 days. A limited amount of RP was incorporated into PC bilayer membranes (approximately 3 mol%). The excess RP separated from the PC bilayers was stabilized as emulsion particles by the PC surface monolayer. When the PC content was less than the solubility in RP, the PC monolayer did not completely cover the hydrophobic RP particle surfaces and separation into oil/water occurred. The miscibility between RP and PC and the lipid composition were critically important for the stability of the dispersed particles (coexistence of emulsion particles [surface monolayer of PC + core of RP] with vesicular particles [bilayer]) of the lipid mixtures.

Anticarcinogenic Agents↗
PubMed2000

Walking speed as a good predictor for the onset of functional dependence in a Japanese rural community population.

OBJECTIVE: to investigate and compare the predictive values of four physical performance measures for the onset of functional dependence in older Japanese people living at home. DESIGN: a population-based prospective cohort study. SETTING: Nangai village, Akita Prefecture, Japan. METHODS: out of the population aged 65 years and older living in Nangai (n = 940) in 1992, we measured hand grip-strength, one-leg standing, and usual and maximum walking speeds in 736 subjects who were independent in the five basic activities of daily living. Their functional status was assessed each year for the subsequent 6 years. The outcome event was the onset of functional dependence, defined as a new disability in one or more of the five basic activities of daily living, or death of a subject who had shown no disability at the previous follow-up. RESULTS: even after controlling for age, sex and a number of chronic conditions, lower scores on each baseline performance measure showed increased risk for the onset of functional dependence. Maximum walking speed was most sensitive in predicting future dependence for those aged 65-74 years, while usual walking speed was most sensitive for people aged > or = 75 years. CONCLUSION: walking speed was the best physical performance measure for predicting the onset of functional dependence in a Japanese rural older population.

Activities of Daily Living↗
PubMed2000

Genetic regulation of anti-erythrocyte autoantibodies and splenomegaly in autoimmune hemolytic anemia-prone new zealand black mice.

New Zealand Black (NZB) mice spontaneously produce anti-erythrocyte autoantibodies (AEA) in association with splenomegaly, thus serving as a model for autoimmune hemolytic anemia. Although these autoimmune traits are inherited as a dominant fashion, expression in F(1) hybrids of NZB and most non-New Zealand strains is suppressed due to the contribution of wild-type modifying genes present in the latter strains. Using chromosomal microsatellite markers in the (C57BL/6 x NZB)F(1) x NZB backcross progeny, we mapped C57BL/6 modifying loci for AEA production and splenomegaly. Generation of AEA was found to be down-regulated by a combined effect of two major independently segregating dominant alleles-one linked to D7MIT30 on chromosome 7 and the other linked to D10MIT42 on chromosome 10. Splenomegaly was modified mainly by a single C57BL/6 allele linked to D4MIT58 on chromosome 4. Thus, the autoimmune hemolytic anemia in the NZB strain is under multigenic control and a combined action of not only susceptibility but also modifying alleles with suppressive activities affects the outcome of disease features in the progeny. There are potentially important candidate genes which may be linked to the regulation of AEA and splenomegaly.

Anemia, Hemolytic, Autoimmune↗