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Eiichi Sato

Publications and source records attributed to Eiichi Sato.

At least 37 records · Page 2Linked to original sources
PubMed2004

Infiltration of CD8+ T cells containing RANTES/CCL5+ cytoplasmic granules in actively inflammatory lesions of human chronic gastritis.

Chronic gastritis is frequently associated with infection of Helicobacter pylori and characterized by tissue infiltration of neutrophils, lymphocytes, and plasma cells. To address the mechanism of lymphocyte infiltration in chronic gastritis, we examined the expression of chemokines and their receptors using frozen sections of chronic gastritis, obtained from 23 patients who underwent gastrectomy for gastric cancer. By immunohistochemistry, lymphocytes in inflamed gastric mucosa expressed CCR5 abundantly, CXCR3 less frequently, and CCR4 sparsely. The numbers of CCR5(+) cells, which were composed of mainly CD8(+) and partly CD4(+) T cells, were positively correlated with the degree of neutrophil infiltration, and decreased in areas with intestinal metaplasia or mucosal atrophy. RANTES/CCL5, one of the ligands of CCR5, was localized mainly in CD8(+) and partly CD4(+) T cells with a characteristic dotted pattern, and such lymphocytes were most densely distributed around the neck region of gastric glands. In situ hybridization confirmed the expression of CCL5 mRNA in these cells, and immunoelectron microscopy revealed localization of CCL5 in the membrane-bound granules, which most probably corresponded to the cytolytic granules of cytotoxic T cells. The numbers of CCL5(+) lymphocytes showed a close correlation with the degree of neutrophil infiltration and markedly decreased in intestinal metaplasia. In conclusion, our data suggest that, together with neutrophils, CCL5(+) T cells, presumably activated cytotoxic T cells, would play important roles in the active inflammatory process of chronic gastritis. Our data also suggest a self-recruiting mechanism involving CCR5 and CCL5 for tissue accumulation of such T cells.

Adult↗
PubMed2004

Demonstration of enhanced K-edge angiography using a cerium target x-ray generator.

The cerium target x-ray generator is useful in order to perform enhanced K-edge angiography using a cone beam because K-series characteristic x rays from the cerium target are absorbed effectively by iodine-based contrast mediums. The x-ray generator consists of a main controller, a unit with a Cockcroft-Walton circuit and a fixed anode x-ray tube, and a personal computer. The tube is a glass-enclosed diode with a cerium target and a 0.5-mm-thick beryllium window. The maximum tube voltage and current were 65 kV and 0.4 mA, respectively, and the focal-spot sizes were 1.0 x 1.3 mm. Cerium Kalpha lines were left using a barium sulfate filter, and the x-ray intensity was 0.48 microC/kg at 1.0 m from the source with a tube voltage of 60 kV, a current of 0.40 mA, and an exposure time of 1.0 s. Angiography was performed with a computed radiography system using iodine-based microspheres. In coronary angiography of nonliving animals, we observed fine blood vessels of approximately 100 microm with high contrasts.

Angiography↗
PubMed2004

Monochromatic polycapillary imaging utilizing a computed radiography system.

A fundamental study on quasi-parallel radiography using a polycapillary plate and a copper-target x-ray tube is described. In the experiments, the tube voltage was regulated from 12 to 22 kV, and the tube current was regulated within 3.0 mA by the filament temperature. The exposure time was controlled in order to obtain optimum x-ray intensity, and the maximum focal spot dimensions were approximately 2.0 x 1.5 mm. The thickness and the inner capillary tube diameter of the polycapillary were 1.0 mm and 25 microm, respectively. Monochromatic x-rays were produced using a 10 microm-thick nickel filter with a tube voltage of 17 kV, and these rays were formed into quasi-parallel beams by the polycapillary. The radiogram was taken using a computed radiography system utilizing imaging plates. In the measurement of image resolution, the spatial resolution hardly varied according to increases in the distance between the resolution-test chart and imaging plate using a polycapillary. A 50 microm tungsten wire could be observed, and fine blood vessels of approximately 100 microm were visible in angiography.

Angiography↗
PubMed2003

Synovial membrane enhancement and bone erosion by magnetic resonance imaging for prediction of radiologic progression in patients with early rheumatoid arthritis.

OBJECTIVE: The aim of this study was to determine the prognostic factors related to radiographic progression in patients with early rheumatoid arthritis (RA) (less than 1 year after onset) undergoing enhanced MRI at entry. METHODS: Demographic characteristics, disease duration, and enhanced MRI of the dominant wrists were recorded at entry. Duration of morning stiffness, number of swollen joints, serum rheumatoid factor (RF), erythrocyte sedimentation rate, C-reactive protein (CRP) level, and radiographs of hands and feet (Sharp/van der Heijde score) were assessed at each follow-up. Outcome was defined as damage seen on radiography. RESULTS: One hundred fourteen patients were followed up for 10 years. Logistic regression analysis showed that high MRI score, CRP, and RF positivity were associated with radiologic progression. The MRI score at baseline was a better predictor than CRP level and RF positivity at entry. CONCLUSION: The assessment of synovial membrane enhancement and bone erosion by MRI of the wrist in early RA is very helpful to predict erosive outcome.

Adult↗
PubMed2003

Mobile submuscular mass resembling a hard-boiled egg: case report.

A 68-year-old woman had a rare mobile mass on her back. The mass was similar to encapsulated fat necrosis except for its unusual stalked appearance, large size, and high degree of mobility underneath the anterior serratus muscle on the back. Based on previous descriptions of encapsulated fat necrosis, the clinical presentation of the mass might be regarded as an extreme example of this rare condition.

Aged↗
PubMed2003

Infiltrating CD8+ T cells in oral lichen planus predominantly express CCR5 and CXCR3 and carry respective chemokine ligands RANTES/CCL5 and IP-10/CXCL10 in their cytolytic granules: a potential self-recruiting mechanism.

Lichen planus is a chronic inflammatory disease of the skin and oral mucosa in which the cell-mediated cytotoxicity is regarded as a major mechanism of pathogenesis. To understand its pathophysiology further, the present study examined the in situ expression of chemokines and chemokine receptors in oral lichen planus. Immunohistochemical analysis of 15 cases has consistently revealed that infiltrating CD4(+) and CD8(+) T cells in the submucosa predominantly expressed CCR5 and CXCR3. Furthermore, infiltrating T cells, particularly CD8(+) T cells, were positive for RANTES/CCL5 and IP-10/CXCL10, the ligands of CCR5 and CXCR3, respectively. By immunoelectron microscopy, these chemokines were localized in the cytolytic granules of CD8(+) T cells. Lesional keratinocytes also overexpressed the ligands of CXCR3, namely, MIG/CXCL9, CXCL10, and I-TAC/CXCL11. Our data suggest that the chemokines signaling via CCR5 and CXCR3, which are known to be selectively expressed by type 1 T cells, are predominantly involved in T-cell infiltration of oral lichen planus. Furthermore, the presence of CCL5 and CXCL10 in the cytolytic granules of tissue-infiltrating CD8(+) T cells expressing CCR5 and CXCR3 reveals a potential self-recruiting mechanism involving activated effector cytotoxic T cells.

CD8-Positive T-Lymphocytes↗
PubMed2003

Influence of the infrapatellar fat pad resection in a synovectomy during total knee arthroplasty in patients with rheumatoid arthritis.

Influence of the infrapatellar fat pad resection in a synovectomy during total knee arthroplasty (TKA) was evaluated in patients with rheumatoid arthritis (RA). Our findings for 120 RA patients at 28 to 38 months after surgery showed that (i) a significant decrease in the number of patients with anterior aching discomfort despite a lower-lying patella was seen in patients with infrapatellar synovectomy compared with patients without infrapatellar synovectomy, and (ii) an increase in the number of patients with anterior aching discomfort, significant limited motion, slight quadriceps weakness, and significant shortening of patellar tendon length and patella height were noted among patients with infrapatellar synovectomy, including fat pad resection, than in patients without infrapatellar synovectomy.

Adipose Tissue↗
PubMed2003

Examination of the risk of continuous leflunomide treatment on the incidence of infectious complications after joint arthroplasty in patients with rheumatoid arthritis.

SYNOPSIS: To determine whether the risk of infectious complications after total joint arthroplasty is increased in rheumatoid arthritis patients who are treated continuously with leflunomide, the incidences of infectious complications in 41 rheumatoid arthritis patients who received continuous leflunomide treatment (leflunomide group) and in 41 patients who did not receive leflunomide within 4 weeks of surgery (nonleflunomide group) were compared. The incidence (6.1%) of local infection after surgery in the leflunomide group (82 procedures) was slightly lower than that (6.3%) in the nonleflunomide group (79 procedures). There were no systemic or deep infections. None of the other variables analyzed were identified as risk factors for postoperative complications. The results indicate that there is no dramatically increased risk of postoperative infectious complications in rheumatoid arthritis patients who continue to be treated with low doses of leflunomide perioperatively.

Journal Article↗
PubMed2003

Role of nitric oxide in regulation of retinal blood flow during hypercapnia in cats.

PURPOSE: To investigate whether nitric oxide (NO) contributes to the regulation of retinal circulation during hypercapnia in cats. METHODS: NG-nitro-L-arginine-methylester (L-NAME; n=8), a NOS inhibitor; NG-nitro-D-arginine-methylester (D-NAME; n=6), the inactive isomer; or phosphate-buffered saline (PBS; n=8) was injected intravitreously into the cat's eye. A selective neuronal nitric oxide synthase (nNOS) inhibitor, 7-nitroindazole (7-NI; n=6), was injected intraperitoneally. Hypercapnia was induced for 10 minutes by inhalation of 5% carbon dioxide with 21% oxygen and 74% nitrogen. The vessel diameter and blood velocity were measured simultaneously in large retinal arterioles in cats by laser Doppler velocimetry and the retinal blood flow (RBF) calculated. Retinal vascular resistance (RVR) was also estimated. RESULTS: In the PBS group, the vessel diameter (9.5% +/- 2.7%, P<0.05), blood velocity (15.6% +/- 4.4%, P<0.05), and RBF (37.2% +/- 3.7%, P<0.05) increased, and the RVR decreased (-26.0% +/- 2.7%, P<0.05) during hypercapnia. In the L-NAME group, those changes were greatly suppressed in response to hypercapnia. D-NAME was inactive with regard to RBF during hypercapnia. The RBF responses to hypercapnia after the 7-NI injection were significantly attenuated compared with those before 7-NI injection (P<0.05). CONCLUSIONS: These results indicate that NO contributes to the increase in RBF during hypercapnia. Furthermore, the NO synthesized by the action of nNOS may participate in regulation of RBF during hypercapnia.

Animals↗
PubMed2003

Pleural effusion caused by prostaglandin E1 preparation.

We encountered a case of bilateral pleural effusion associated with prostaglandin E(1) (PGE(1)) preparation. A 75-year-old man underwent replacement surgery for an amputated hand. PGE(1) was administered at 120 micro g/d to maintain circulation after vascularization. From day 7 of administration, respiratory distress developed. On day 12, pleural effusion was observed bilaterally. By discontinuing PGE(1) and improving hypoalbuminemia, pleural effusion resolved rapidly. This is the first case report of PGE(1)-induced pleural effusion; like other drug-induced pleural effusions, discontinuing the drug resulted in rapid improvement. Although a rare complication, pleural effusion has to be suspected when a patient receiving PGE(1) experiences difficulty with breathing.

Aged↗
PubMed2003

Irradiation of intense characteristic x-rays from weakly ionized linear molybdenum plasma.

In the plasma flash x-ray generator, a high-voltage main condenser of approximately 200 nF is charged up to 55 kV by a power supply, and electric charges in the condenser are discharged to an x-ray tube after triggering the cathode electrode. The flash x-rays are then produced. The x-ray tube is a demountable triode that is connected to a turbo molecular pump with a pressure of approximately 1 mPa. As electron flows from the cathode electrode are roughly converged to a rod molybdenum target of 2.0 mm in diameter by the electric field in the x-ray tube, weakly ionized linear plasma, which consists of molybdenum ions and electrons, forms by target evaporation. At a charging voltage of 55 kV, the maximum tube voltage was almost equal to the charging voltage of the main condenser, and the peak current was about 20 kA. When the charging voltage was increased, the linear plasma formed, and the K-series characteristic x-ray intensities increased. The K lines were quite sharp and intense, and hardly any bremsstrahlung rays were detected. The x-ray pulse widths were approximately 700 ns, and the time-integrated x-ray intensity had a value of approximately 35 micro C/kg at 1.0 m from the x-ray source with a charging voltage of 50 kV.

Electrodes↗
PubMed2002

Intra-articular injection of high molecular weight hyaluronan after arthrocentesis as treatment for rheumatoid knees with joint effusion.

OBJECTIVE: The aim of this study was to find if a complete synovial fluid aspiration before injection of intra-articular high molecular weight hyaluronan influences the treatment result for knees with rheumatoid arthritis (RA), including joint effusion and the prognostic factors related to clinical effect. METHODS: The arthritic knees including effusion were randomized to arthrocentesis or no arthrocentesis before the hyaluronan (1.9-2.5 x 10(6)) was injected into knee joints five times every week. All patients were followed up for 6 months. RESULTS: One hundred eighteen RA patients (80 knees in the arthrocentesis group, 81 knees in the no-arthrocentesis group) were included. The proportion of no relapses in the arthrocentesis group was higher than that in the no-arthrocentesis group. In the arthrocentesis group, regression analysis showed that duration of knee arthritis (<5 months), CRP (<4 mg/dl), and Larsen grade (<grade II) were the significant predictors. CONCLUSIONS: Arthrocentesis is effective in reducing the risk for arthritis relapse by intra-articular hyaluronan injection to rheumatoid knees with joint effusion. Predicting responders are duration of knee arthritis, CRP, and radiological scores.

Adjuvants, Immunologic↗
PubMed2002

New classification of pancreatic intraductal papillary-mucinous tumour by mucin expression: its relationship with potential for malignancy.

In previous studies of the expression of MUC1 (membrane-bound type mucin) and MUC2 (intestinal type secretory mucin) in pancreatic tumours, invasive ductal carcinoma (IDC) usually showed MUC1+ and MUC2- expression, whereas intraductal papillary-mucinous tumour (IPMT) showed MUC1- and MUC2+ expression. Recently, however, many IPMTs have been collected, a considerable number of which have shown MUC1- and MUC2- expression. In the present study, the clinicopathological features were examined of 18 IPMTs with MUC2+ and 32 IPMTs with MUC2-, and their potential for malignancy was compared. Most of the IPMTs with MUC2+ were composed of dark columnar cells, whereas most of the IPMTs with MUC2- were composed of clear columnar cells. The incidence of carcinomatous change and invasive proliferation of the carcinoma in the MUC2+ tumours was significantly higher than in the MUC2- tumours. The clinical outcome for the patients with IPMT showing the MUC2+ pattern tended to be worse than for those with IPMT showing the MUC2- pattern, although the overall outcome for the two types of IPMT was significantly better than for those with IDC. Because of the differences in mucin expression pattern, morphological appearance and potential for malignancy between the two types of IPMT, we believe that they belong to different neoplastic lineages and that it may be reasonable to classify them as different entities, although the WHO classification contains a single clinicopathological entity of IPMT forming an adenoma-carcinoma sequence. In conclusion, our classification of IPMTs by MUC2 expression pattern may be of value in the better assessment of the biological behaviour of IPMTs and their potential for malignancy.

Adenocarcinoma, Mucinous↗
PubMed2002

The expression of several types of mucin is related to the biological behavior of pancreatic neoplasms.

BACKGROUND/PURPOSE: Mucins are high molecular weight glycoproteins that have oligosaccharides attached to the apomucin protein backbone by O-glycosidic linkages. Here, we report the expression of MUC1 mucin (membrane-bound mucin), MUC2 mucin (intestinal-type secretory mucin), and MUC5AC mucin (gastric-type secretory mucin) in invasive ductal carcinomas (IDCs; n = 46) and intraductal papillary-mucinous neoplasms (IPMNs; n = 33) of the pancreas, and the relationship of this expression with malignant potential. METHODS: To clarify the precise expression pattern of mucins in IPMNs, we classified IPMNs into three histologic subtypes; IPMN-dark cell type ( n = 19), IPMN-clear cell type ( n = 10), and IPMN-compact cell type ( n = 4). RESULTS: IDC, with a poor outcome, showed a pattern of MUC1(+), MUC2(-), and MUC5AC(+ or -). In contrast, IPMN-dark cell type tumors, with a fairly favorable outcome, showed a pattern of MUC1(-), MUC2(+), and MUC5AC (+), and IPMN-clear cell type tumors, with a favorable outcome, showed a pattern of MUC1(-), MUC2(-), and MUC5AC(+). On the other hand, IPMN-compact cell type tumors showed a pattern of MUC1(+), MUC2 (-), and MUC5AC(+). In IPMN-dark cell type tumors with carcinomatous change showing invasive growth, the invasive areas acquired a characteristic of MUC1 expression that was usually seen in IDC, although their main noninvasive lesions showed no MUC1 expression. The IPMN-compact cell type tumors usually showed high cellular atypia and frequent MUC1 expression, even in the noninvasive areas. CONCLUSIONS: Our study of the mucin expression pattern in IDC and IPMN shows that this pattern may be related to the biological behavior of pancreatic tumors and their malignant potential.

Carcinoma, Pancreatic Ductal↗
PubMed2002

MUC1 mucin expression in follicular dendritic cells and lymphoepithelial lesions of gastric mucosa-associated lymphoid tissue lymphoma.

Membrane-associated mucin MUC1 is expressed in various adenocarcinoma cells and active T lymphocytes. We tried to find out whether MUC1 is expressed in gastric mucosa-associated lymphoid tissue (MALT) lymphoma lesion. MUC1 was not expressed in infiltrating T lymphocytes; however, MUC1 was found on the cell surface of follicular dendritic cells (FDC) of germinal centers and in the epithelial cytoplasm of lymphoepithelial lesion (LEL) of the lymphoma, which were immunohistochemically detected by monoclonal antibodies DF3 and MY.1E12. MUC1 was also expressed in the FDC of control cases (gastrectomy specimen containing reactive lymphoid follicles, n = 10, MUC1/ DF3, 100%; MUC1/MY.1E12, 40%), and FDC in MALT lymphomas (n = 59) showed lower MUC1 expression rates (MUC1/ DF3, 32%; MUC1/MY.1E12, 0%) than the control (P < 0.001). Lymphoepithelial lesion in the low-grade MALT lymphomas (n = 23) showed a higher MUC1/DF3 expression rate (30%) than those in the high-grade MALT lymphomas (n = 36; 6%; P < 0.05). T lymphocytes in the surface mucosa were more frequent in MALT lymphoma (91.4 +/- 80.6/unit area) than those in the control (20.0 +/- 23.6) (P < 0.001). S100-positive dendritic cells around LEL were more frequent in the low-grade (19.0 +/- 9.4/unit area) than in the high-grade (11.7 +/- 9.7) (P < 0.005). This study demonstrated MUC1 mucin expression on FDC for the first time. Mucosa-associated lymphoid tissue lymphoma, especially low-grade, shows immunologically active state, where FDC MUC1 expression may be suppressed by some factors released from lymphoma cells. Further study to elucidate the pathogenetic role of MUC1 in MALT lymphoma is necessary.

Aged↗
PubMed2002

The effect of nitric oxide on retinal blood flow during hypoxia in cats.

PURPOSE: To investigate how nitric oxide (NO) contributes to the regulation of retinal circulation during rest and hypoxia in cats. METHODS: N(G)-nitro-L-arginine-methyl ester (L-NAME; n = 7), an NO synthase inhibitor; N(G)-nitro-D-arginine methyl ester (D-NAME; n = 6), the inactive isomer; or phosphate-buffered saline (PBS; n = 7) was injected intravitreously. Hypoxia was induced in the cats by the administration of 10% oxygen. Vessel diameter and blood velocity were measured simultaneously in the anesthetized cats with a laser Doppler velocimetry system, and the retinal blood flow (RBF) and wall shear rate (WSR) were calculated as an index of shear stress on the retinal vessel wall. RESULTS: After intravitreous injection of L-NAME, the vessel diameter (-8.1% +/- 2.0%, P < 0.01), velocity (-17.0% +/- 3.7%, P < 0.01), and RBF (-29.4% +/- 4.6%, P < 0.01) significantly decreased compared with the preinjection level. In the PBS group, maximum increases above the prehypoxia diameter (13.7% +/- 3.5%, P < 0.01), velocity (39.5% +/- 8.6%, P < 0.01), RBF (73.9% +/- 10.6%, P < 0.01), and WSR (28.3% +/- 7.1%, P < 0.01) were observed during hypoxia. In the L-NAME group, those changes substantially decreased in response to hypoxia. D-NAME was inactive with regard to RBF during rest and hypoxia. CONCLUSIONS: These results suggest that NO may be continuously produced in the retina during rest and contributes to increased RBF during hypoxia. In addition, the increased WSR during hypoxia indicates that NO plays an important role in retinal hypoxic hyperemia through a flow-induced mechanism.

Animals↗