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S Hayashi

Publications and source records attributed to S Hayashi.

At least 415 records · Page 23Linked to original sources
PubMed1998

Development of agents for reinforcement of fluorescence on near-infrared ray excitation for immunohistological staining.

Fluorescence intensity of indocyanine green (ICG) derivative (ICG-sulfo-OSu) was too low for its use to detect microlesions. Therefore, we examined the effects of reinforcement agents on ICG-sulfo-OSu labeled antibodies. Solutions of distearoylphosphatic acid sodium salt (DSPA) and octylglucoside (OG) in physiological phosphate buffered saline (PBS) were found to increase the intensity of fluorescence of ICG-sulfo-OSu labeled antibodies, with shift in the fluorescence peak wavelength from 804 to 821 nm.

Antibodies↗
PubMed1998

Sensitization to hyperthermia by intracellular acidification of C6 glioma cells.

Hyperthermia has been introduced as a new modality of treatment for glioma. In these experiments, the cytotoxicity of hyperthermia in C6 glioma cells was enhanced by increasing the intracellular acidity with amiloride and/or 4,4'-diisothiocyanatostilbene-2,2' disulfonic acid (DIDS). Intracellular pH (pHi) is regulated mainly by Na+/H+ and HCO3-/Cl- antiports through the cell membrane, and amiloride acts on the former, DIDS on the latter to lower pHi. The cellular thermosensitivity to clinically achievable brain hyperthermia at 42 degrees C was enhanced by 0.5 mM amiloride (Na+/H+ antiport inhibitor). T0 values (T0 = the heating period required to reduce experimental survival rate by 1/e) at 42 degrees C without and with amiloride was 192 and 81 min, respectively. The addition of DIDS (HCO3-/Cl- antiport inhibitor) further enhanced. T0 value was 25 min. Fluorophotometric measurement of pHi was employed using the pH sensitive dye, bis(carboxyethyl)carboxyfluorescein, which is trapped in viable cells. The average pHi in control C6 glioma cells in pH 7.2 media was 7.21. In the untreated cells heated at 42 degrees C for 1 hour, the pHi was 7.12. The pHi of the cells heated in the presence of amiloride was decreased to 6.83. The pHi was further lowered to 6.67 by the treatment with amiloride in combination with DIDS for 2 hours. Hyperthermia with amiloride and DIDS may be a more effective treatment for malignant gliomas.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗
PubMed1998

Immunological determination of faecal haemoglobin concentrations in dogs.

Faecal haemoglobin (Hb) concentrations in apparently healthy experimental Beagle dogs and in dogs of various breeds kept in private households or at breeders were measured by reversed passive latex agglutination (RPLA) and enzyme-linked immunosorbent assay (ELISA) in an effort to define the physiological concentrations of faecal Hb in the dog. In 88% (53) of 60 experimental Beagle dogs (30 males and 30 females), the RPLA titres were 1:2 and 1:8 and the faecal Hb concentrations ranged from 40.0 to 431.5 (mean 184.1 +/- 92.6) micrograms/g faeces by ELISA. No significant difference was found in Hb levels or RPLA titres between males and females. Seven dogs (12%) had significantly greater RPLA titres and Hb concentrations by ELISA than the remaining dogs. In 84% (45) of the 53 dogs kept in private households or at breeders, the RPLA titres were < 1:1 to 1:8 and the faecal Hb concentrations ranged from 7.1 to 456.7 (mean 137.5 +/- 128.7) micrograms/g faeces in ELISA. Eight of these dogs (15.1% of 53 dogs) had significantly greater RPLA titres and Hb concentrations by ELISA than the remaining dogs. There were no significant differences between the Beagles and dogs kept in private households or at breeders. In conclusion, in 98 (86.7% of 113) dogs the physiological concentrations of RPLA titres were < 1:1 to 1:8 and the faecal Hb concentrations were 143.5-185.1 micrograms/g (95% confidence level). Approximately 13.3% of apparently healthy dogs had higher faecal Hb concentrations, suggesting the presence of subclinical haemorrhages. Four dogs suffering from colorectal cancer also had high faecal Hb concentrations.

Animals↗
PubMed1998

Physiological levels of C-reactive protein in normal canine sera.

This study was undertaken to investigate whether the level of C-reactive protein (CRP) in the serum of dogs undergoes physiological variation, using 10 normal Beagle dogs (5 males and 5 females), 1-2 years old, maintained in a healthy condition in a controlled environment. The CRP concentration in the sera collected seven times each day at intervals of approximately 3 h ranged from 0.8 to 16.4 micrograms/ml (mean 5.06 +/- 3.60) in one experiment and from 0.8 to 14.0 micrograms/ml (mean 4.50 +/- 2.80) in a second experiment. On examining the 24-h variations in the concentration of CRP in serum, neither consistent changes nor a definite pattern of circadian rhythm was detected. During 28 days observation, only very slight changes, which seemed attributable to analytical errors, were seen in any of the dogs, except one. The concentration of CRP in the serum during the 28 days ranged from 0.8 to 22.6 micrograms/ml (mean 3.65 +/- 1.40). The concentrations underwent no significant variations in individual dogs, but significant differences were found between the dogs (p < 0.01).

Animals↗
PubMed1998

Fatal cytomegalovirus interstitial pneumonia following autologous peripheral blood stem cell transplantation. Fukuoka Bone Marrow Transplantation Group.

A 52-year-old Japanese woman suffering from AML (FAB classification M4) in her first remission received an autologous peripheral blood stem cell transplant (APBSCT). She was seropositive for CMV prior to APBSCT. Her post-APBSCT course was complicated with CMV-associated disease and hemophagocytic syndrome. Finally, CMV interstitial pneumonia developed and death ensued. Even after APBSCT, there can be a short period of immune deficiency resembling that occurring following allogeneic or autologous BMT. CMV infection must be considered in the differential diagnosis in cases of unexplained fever or pneumonia following APBSCT.

Cytomegalovirus Infections↗
PubMed1998

Donor lymphocyte transfusion for the treatment of Epstein-Barr virus-associated lymphoproliferative disorder of the brain.

EBV-associated lymphoproliferative disorder (LPD) is a rare but serious complication in marrow transplant recipients. A 31-year-old Japanese woman in the second chronic phase of CML received an allogeneic BMT from her HLA 2-locus-incompatible 62-year-old father. Around day +200, she developed EBV-LPD of the right parieto-temporal lobe which caused slowly progressive left hemiparesis. Two courses of donor lymphocyte transfusions (DLT) of 10(6)CD3+ T cells/kg of body weight failed to suppress her central nervous system (CNS) EBV-LPD. The patient died of recurrent blastic crisis of CML. This case suggests that DLT may be ineffective for the treatment of CNS EBV-LPD.

Adult↗
PubMed1998

Establishment of complement-resistant retroviral vector by homologous restriction factor 20 gene.

Homologous restriction factor 20 (HRF20, CD59) is one of the complement regulatory factors. In this study, the complement-resistant retroviral vector, which possesses the HRF20 gene as a selection gene, was constructed and examined. The virus-producing cell, transduced with complement-resistant retroviral vector, was established after complement-dependent selection. NIH3T3 and PK15 cells transduced with this virus-producing cell were successfully selected by complement-dependent selection, which showed significant expression of the HRF20 antigen. In addition, these cells, transduced with tissue plasminogen activator (tPA) cDNA using complement-resistant retroviral vector, expressed tPA antigen after complement-dependent selection. These findings suggest that complement-resistant retroviral vector can be used for the double transduction of HRF20, as well as other genes.

3T3 Cells↗
PubMed1998

Correlation of plasma monocyte chemoattractant protein-1 (MCP-1) and monocyte inflammatory protein-1alpha (MIP-1alpha) levels with disease activity and clinical course of sarcoidosis.

MCP-1 and MIP-1alpha exhibit chemotactic activity toward macrophages/monocytes and induce the production of inflammatory cytokines affecting granuloma formation. Up-regulated expression of MCP-1 and MIP-1alpha in the affected organ of sarcoidosis has been shown; however, the relationship between their plasma levels and the clinical course of this disease has not been determined. In the present study we measured plasma MCP-1 and MIP-1alpha levels in 26 patients with active sarcoidosis by ELISA in order to assess the state of MCP-1 and MIP-1alpha in this disease. Most patients in this study (21/26) had clinical evidence of extrathoracic disease in addition to pulmonary involvement. In addition, a high proportion of patients (n = 15) showed spontaneous remission of disease, whereas five patients showed no spontaneous remission and six patients were treated with corticosteroids over the 2-year period of study. At the time of diagnosis, both plasma MCP-1 and MIP-1alpha levels in patients with active sarcoidosis were significantly higher than in the normal controls. The levels of these cytokines in patients with extrathoracic disease were compatible with those in patients without extrathoracic disease. A longitudinal evaluation of plasma MCP-1 and MIP-1alpha levels showed that the changes in both cytokines were closely related to the clinical course of sarcoidosis. These results suggest that plasma MCP-1 and MIP-1alpha may be useful parameters for monitoring the clinical course of sarcoidosis. In addition, plasma MCP-1 and MIP-1alpha may reflect subclinical evidence of extrathoracic sarcoidosis and may play a role in initiating monocyte migration into the tissue.

Adult↗
PubMed1998

Actions of hepatocyte growth factor as a local modulator in the kidney: potential role in pathogenesis of renal disease.

Endothelial cells are known to secrete various vasoactive substances that may control mesangial cell growth, whereas mesangial cells also secrete various growth factors and cytokines that may regulate endothelial cells. Therefore, it is apparent that cell-cell interactions among renal cells are important in the control of renal function. Indeed, co-culture of endothelial cells with mesangial cells resulted in a significant decrease in mesangial cell growth. However, the exact mechanisms of maintaining the cell-cell interactions are not yet understood. We have focused on the role of hepatocyte growth factor (HGF) in the regulation of cell-cell interactions, since HGF has been reported to have many organ protective functions in the kidney. Our present data demonstrated that addition of recombinant HGF (rHGF) stimulated DNA synthesis and growth of endothelial cells in a dose-dependent manner. However, there was no stimulatory effect of rHGF on the growth of mesangial cells in the time and dose-dependent manner. Therefore, we examined the presence of the local renal HGF system and its potential role in renal disease. The presence of secreted local HGF was observed in the conditioned medium from endothelial and mesangial cells. The presence of HGF mRNA was also detected in endothelial and mesangial cells. Interestingly, the specific receptor of HGF, c-met, was also expressed in both cells. Next, regulation of local HGF secretion was studied under stimulation with rHGF, angiotensin (Ang) II, and transforming growth factor (TGF)-beta. Of importance, rHGF significantly stimulated local HGF secretion from mesangial cells by positive feedback. In contrast, TGF-beta significantly decreased HGF secretion in mesangial cells and endothelial cells. Angiotensin II also significantly decreased local HGF production in mesangial cells in a dose-dependent manner. Finally, the effect of local HGF production from mesangial cells was studied using a co-culture system. Co-culture of mesangial cells with endothelial cells resulted in a significant increase in number of endothelial cells, which was abolished by co-incubation with neutralizing anti-HGF antibody. Overall, these results demonstrated the local production of HGF, which has stimulatory effects on growth of endothelial cells, but not mesangial cells. Local HGF secretion from mesangial cells may maintain the growth of endothelial cells. Negative regulation of local HGF production by Ang II and TGF-beta may play an important role in the pathogenesis of renal disease. Taken together, dysfunction of cell-cell regulation in the kidney due to decreased local HGF production may be an initial trigger for the development of renal disease such as glomerulonephritis.

Angiotensin II↗
PubMed1998

Close associations between prevalences of dominantly inherited spinocerebellar ataxias with CAG-repeat expansions and frequencies of large normal CAG alleles in Japanese and Caucasian populations.

To test the hypothesis that the frequencies of normal alleles (ANs) with a relatively large number of CAG repeats (large ANs) are related to the prevalences of the dominant spinocerebellar ataxias (SCAs)-SCA types 1, 2, 3 (Machado-Joseph disease), 6, and dentatorubral-pallidoluysian atrophy (DRPLA)-we investigated the relative prevalences of these diseases in 202 Japanese and 177 Caucasian families and distributions of the number of CAG repeats of ANs at these disease loci in normal individuals in each population. The relative prevalences of SCA1 and SCA2 were significantly higher in Caucasian pedigrees (15% and 14%, respectively) than in Japanese pedigrees (3% and 5%, respectively), corresponding to the observation that the frequencies of large ANs of SCA1 (alleles >30 repeats) and of SCA2 (alleles >22 repeats) were significantly higher in Caucasians than in Japanese. The relative prevalences of MJD/SCA3, SCA6, and DRPLA were significantly higher in Japanese pedigrees (43%, 11%, and 20%, respectively) than in Caucasian pedigrees (30%, 5%, and 0%, respectively), corresponding to the observation that the frequencies of large ANs of MJD/SCA3 (>27 repeats), SCA6 (>13 repeats), and DRPLA (>17 repeats) were significantly higher in Japanese than in Caucasians. The close correlations of the relative prevalences of the dominant SCAs with the distributions of large ANs strongly support the assumption that large ANs contribute to generation of expanded alleles (AEs) and the relative prevalences of the dominant SCAs.

Asian People↗
PubMed1998

Identification of the gene loci that predispose to rheumatoid arthritis.

We have searched the human genome for genes that predispose to rheumatoid arthritis (RA) using fluorescence-based microsatellite marker analysis and affected sib-pair linkage study. A panel of 41 Japanese families, each with at least two affected siblings, was typed for genome-wide 358 polymorphic microsatellite marker loci. Markers were amplified by the PCR using fluorescence-tagged primers and sized based on the difference of CA repeats on DNA. Linkage analysis was made using maximum lod score (MLS). The MLS for D1S214 and D8S556 was 3.27 and 3.33, while the MLS for the HLA-DRB1 region was <3.0. According to detailed analysis by single-point analysis using MAPMAKER/SIBS, the MLS for D1S253 and D1S214 was 3.77 and 3.58. The MLS by multipoint analysis was 6.13 for D1S253. The MLS for D8S556 by single-point analysis was 4.20. The MLS for DXS1232 was 2.35 by single-point analysis, whereas the MLS for the region 2 cM right to DXS1232 and the region between DXS1227 and DXS1200 was 3.03 and 2.93 by multi-point analysis. Three principal chromosome regions of linkage, D1S253/214, D8S556 and DXS1232, have been identified which we call RA1, RA2 and RA3 for RA disease loci.

Arthritis, Rheumatoid↗
PubMed1998

Transcription factor decoy for nuclear factor-kappaB inhibits tumor necrosis factor-alpha-induced expression of interleukin-6 and intracellular adhesion molecule-1 in endothelial cells.

BACKGROUND: Several cytokines and adhesion molecules released from endothelium play an important role in inflammation, immune responses, and probably atherogenesis. OBJECTIVE: To determine whether the transcription factor nuclear factor-kappaB mediated expression of these genes involved in the inflammatory response of endothelial cells to tumor necrosis factor-alpha, by using transcription factor decoy oligodeoxynucleotides. DESIGN AND METHODS: We first transfected fluorescein isothiocyanate (FITC)-labeled double-stranded oligodeoxynucleotides into endothelial cells by a cationic liposome-mediated method of gene transfer. We then confirmed that the decoy oligodeoxynucleotides could block binding of nuclear factor-kappaB to its specific cis element effectively. In addition, we transfected the reporter gene chloramphenicol acetyltransferase driven by three repeated nuclear factor-kappaB binding sequences in the promoter and enhancer region. RESULTS: FITC-labeled oligodeoxynucleotides were detected in the nuclei of approximately 70% of the total cells. Tumor necrosis factor--stimulated expression of chloramphenicol acetyltransferase was partially inhibited by transfection of nuclear factor-kappaB decoy oligodeoxynucleotides, but not by transfection of scrambled oligodeoxynucleotides. Also nuclear factor-kappaB decoy oligodeoxynucleotides but not scrambled oligodeoxynucleotides inhibited tumor necrosis factor-induced expression of interleukin-6 and intracellular adhesion molecule-1 both at the messenger RNA and at protein level (assessed by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay). CONCLUSION: Our results demonstrate that nuclear factor-kappaB decoy oligodeoxynucleotides transfected by cationic liposome method inhibited tumor necrosis factor--induced expression of interleukin-6 and intracellular adhesion molecule-1 in endothelial cells.

Animals↗
PubMed1998

Hepatocyte growth factor as a potential index of complication in diabetes mellitus.

OBJECTIVE: Diabetes mellitus (DM), characterized by the premature development of microvascular and macrovascular disease, shows a loss of vasodilatory properties of resistance vessels. However, the mechanisms of endothelial dysfunction in diabetes have not yet been clarified. Hepatocyte growth factor (HGF) in vascular cells was down-regulated by high glucose levels, potentially accelerating the endothelial dysfunction in DM. In this study, the serum HGF level was measured to investigate further the role of HGF in DM. METHODS: Tissue and circulating HGF levels were measured in the KKAy mouse, a rodent model of non-insulin-dependent diabetes mellitus (NIDDM), and lean C57 BL control mice. Then, serum HGF concentrations were measured in NIDDM patients without liver, kidney or lung damage. For the study of serum HGF concentration, 30 normotensive and age-matched 58 DM patients were studied. The 58 DM patients were divided into 26 patients without hypertension and 32 patients with hypertension [22 patients without hypertensive complications (WHO I) and 10 patients with hypertensive complications (WHO II + III)]. RESULTS: The serum HGF concentration in KKAy mice was significantly lower than that in control mice (P < 0.01), at 14 weeks of age when they exhibit features of diabetes. Similarly, tissue HGF concentrations in the heart and kidney were decreased significantly in KKAy mice compared with control C57 BL mice (P< 0.05). The serum HGF concentration showed a significant negative correlation with hemoglobin (Hb) A(Ic) concentration (P< 0.01, r= -0.41). Since the serum HGF concentration is a potential index of the severity of hypertension, the serum levels of HGF in DM patients without and with hypertension were examined. The serum HGF concentration in DM patients without hypertension was significantly lower than that in normal subjects (P< 0.05), whereas that in DM patients with hypertension was significantly higher than that in normal subjects (P < 0.01). Moreover, the serum HGF concentration in DM patients with hypertensive complications was further higher than that in others (P < 0.01). CONCLUSION: The present data showed that serum, cardiac and renal HGF concentrations in KKAy mice were significantly decreased compared with control mice. Therefore, a decrease in local HGF may be a trigger of endothelial dysfunction in DM. Clinical data also demonstrated a significant negative correlation between serum HGF and HbA(Ic) concentrations in diabetic patients without complications. In contrast, the serum concentration of HGF was significantly elevated depending on the severity of hypertension. These results suggest that HGF may be a new index of complications such as hypertension in DM.

Animals↗
PubMed1998

HIV-associated eosinophilic pustular folliculitis: successful treatment of a Japanese patient with UVB phototherapy.

We report the successful treatment with ultraviolet B phototherapy of a patient with HIV-associated eosinophilic pustular folliculitis. We were able to observe the clinical and therapeutic course for about one year and three months. This 35-year-old homosexual Japanese man presented with disseminated, discrete, follicular, erythematous papules with intense pruritus over his face, neck, chest wall, and upper back. Initially, the eruption responded to therapy with topical or oral indomethacin and oral H1 antihistamine. However, the eruption was highly prone to recurrence, and it gradually failed to respond to these therapies. The eruption became chronic and persistent and manifested the excoriated, prurigo-like nodules that are typical of reported pruritic papular eruption, suggesting that this skin disease and HIV-associated eosinophilic pustular folliculitis are two forms of the same disease entity. UVB phototherapy in small doses was very effective for the persistent eruption, and no recurrence of the eruption was noted during or since the six-month maintenance therapy (once a week at a dose equivalent to 0.75 of the minimal erythema dose) (9 months total). No unfavorable side effects have been observed during or after the UVB phototherapy (cumulative UVB doses of 2,320 mJ/cm2).

Adult↗
PubMed1998

Utilization of proteinase K-treated cells as lipopolysaccharide antigens for the serodiagnosis of Helicobacter pylori infections.

We have evaluated the use of proteinase K (PK)-treated cells isolated from Helicobacter pylori as lipopolysaccharide (LPS) antigens in an immunoblot assay and an enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of H. pylori infection. The sera from patients with chronic gastritis, gastric ulcer, duodenal ulcer or gastric cancer, and from healthy adults with or without H. pylori infection were assayed with three commercial serodiagnostic kits (HM-CAP, Helico-G, and G.A.P. II) and novel methods relying on the use of PK-treated cells. The PK-treated cells used in these assays were selected on the basis of their possibility to possess a common epitope in the O-polysaccharides of H. pylori, which is known to be highly immunogenic in humans. Of the sera from these patients, 71-94% were positive with the commercial kits, 97% with immunoblot assay, and 90% with ELISA. On the other hand, of the healthy adults infected with H. pylori, 72-97% were positive with the commercial kits, 86% with immunoblot assay, and 72% with ELISA. PK-treated cells that did not contain the common epitope were unsuitable as an antigen for immunoblot assay or ELISA. Furthermore, the reactivity of these sera reacted specifically with H. pylori PK-treated cells but not with LPSs from other gram-negative bacteria, such as Campylobacter, Proteus, Bordetella, and Salmonella. These results demonstrate that the serological assays relying on the use of H. pylori PK-treated cells possessing a highly antigenic epitope are potentially useful as a serodiagnostic test for H. pylori infection.

Adult↗
PubMed1998

Apoptosis of lymphocytes in mice administered lipopolysaccharide from Leptospira interrogans.

We report that administration of leptospiral lipopolysaccharide (LPS) in mice results in massive surface marker changes in the lymphocytes of the spleen. It appears that many of these changes relate to the large number of cells undergoing apoptosis. It is also shown that tumor necrosis factor-alpha (TNF-alpha) induces similar effects and is produced in large quantities after injection of leptospiral LPS. It is likely that cytokines such as TNF-alpha are involved in apoptosis.

Animals↗