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T Nishimura

Publications and source records attributed to T Nishimura.

At least 127 records · Page 7Linked to original sources
PubMed2001

[Nitric oxide-dependent inhibition of platelet aggregation in elderly patients with hypercholesterolemia].

Hypercholesterolemia reduces production of nitric oxide (NO), a potent inhibitor of platelet aggregation, in endothelial cells. Recently platelet has been found to have NO synthase. Hypercholesterolemia may influence platelet NO production. We investigated NO-dependent inhibition of platelet aggregation in elderly hypercholesterolemic patients with total cholesterol (Tchol) of 240 mg/dl or more (n = 21). In elderly controls with Tchol less than 240 mg/dl (n = 61), L-arginine (5-50 mM) inhibited ADP-induced platelet aggregation in a dose-dependent manner (42.4% inhibition at 50 mM). However, L-arginine did not inhibit platelet aggregation in elderly hypercholesterolemic patients. L-arginine increased cyclic GMP production in elderly controls, but not in hypercholesterolemic patients (p < 0.02). Hypercholesterolemic patients showed increased platelet aggregation compared with elderly controls(p = 0.018). L-nitro-arginine methyl ester 12.5-50 uM increased platelet aggregation in both groups. Superoxide dismutase improved L-arginine inhibition of platelet aggregation in elderly hypercholesterolemic patients (p = 0.02). LDL cholesterol of 160 mg/dl or more was an independent predictor for loss of L-arginine inhibition of platelet aggregation (relative risk 3.9, p = 0.0098). This result suggests that hypercholesterolemia causes decreased NO-dependent inhibition of platelet aggregation due to reduced NO utilization. NO-dependent platelet aggregation may be a powerful tool for detection of vascular injury.

Aged↗
PubMed2001

Characterization of glycans in a lactoferrin isoform, lactoferrin-a.

The presence of glycan at Asn-281 in bovine lactoferrin-a, which has a higher molecular weight than regular lactoferrin-b, was found in our previous study. The present work was performed to clarify the structures of the glycans linked to the five N-glycosylation sites in lactoferrin-a and to compare them with those of glycans linked to lactoferrin-b. In lactoferrin-a, the glycans linked to Asn-233 and Asn-545 were of the high-mannose type, whereas those present at Asn-368 and Asn-476 were complex-type ones. These glycans possessed heterogeneous structures. A comparative study of the glycans on bovine lactoferrin-a and bovine lactoferrin-b by HPLC showed that the structures of the glycans linked to Asn-368, Asn-476, and Asn-545 were very similar, the exception being the glycan linked to Asn-233. In addition, analysis of the structure of the glycan bound to Asn-281 present only in lactoferrin-a showed it possessed the heterogeneous structure of a complex-type glycan in which the structures Man3GlcNAc2, Man3GlcNAc4, Man3GlcNAc4Fuc are suggested to be present based on HPLC retention times only.

Animals↗
PubMed2001

[Laparoscopic extraperitoneal bladder diverticulectomy: an initial case report].

We report a case with a large bladder diverticulum caused by the bladder outlet obstruction, which was successfully treated with laparoscopic extraperitoneal diverticulectomy. The patient was a 71-year-old man, who had had dysuria, micturition pain and cloudy urine. We found the patient to have benign prostatic hyperplasia and a large diverticulum of the bladder. We removed the diverticulum by laparoscopic procedure and then the prostate by transurethral resection on September 24th, 1998. Before the diverticulectomy, we placed a ureteral stent in the left ureter and 8Fr Foley catheters in the diverticulum and bladder. A working space was made by dilation using a balloon dilator. After removing the diverticulum, we made 5 stitches to close the bladder wall. After the surgery, a 22Fr Foley catheter was placed and removed on the 9th postoperative day. Patient had a satisfactory micturition and was discharged on the postoperative 15th day. Laparoscopic diverticulectomy might be a modality for symptomatic bladder diverticulum, because it is minimally invasive and can completely remove bladder diverticulum.

Aged↗
PubMed2001

Association of induced disease resistance of rhododendron seedlings with inoculation of Streptomyces sp. R-5 and treatment with actinomycin D and amphotericin B to the tissue-culture medium.

Seedlings of rhododendron were treated by adding Streptomyces sp. strain R-5, actinomycin D and/or amphotericin B to the tissue-culture medium. HPLC analysis showed that all of the treated seedlings contained these antibiotics at concentrations higher than the suppressive levels to mycelial growth of Pestalotiopsis sydowiana, a major pathogen of rhododendron. Occurrence of disease caused by this fungus in the seedlings was suppressed by treatment of the medium surface with strain R-5, but not by treatment with these antibiotics, suggesting that growth of strain R-5, an antibiotic producer, could be essential for induction of disease resistance in tissue-cultured seedlings of rhododendron.

Amphotericin B↗
PubMed2001

Serial changes in 14C-deoxyglucose and 201Tl uptake in autoimmune myocarditis in rats.

UNLABELLED: This study was designed to examine the relationships between the uptake of 14C-deoxyglucose (DG) and the uptake of 201Tl in a rat model of autoimmune myocarditis. METHODS: Autoimmune myocarditis was induced in normal rats by immunization with pig cardiac myosin. Dual-tracer autoradiography with DG and 201Tl was performed on frozen slices of the animals' hearts 3 wk (acute phase), 8 wk (subacute phase), and 14 wk (chronic phase) (each n = 5) after immunization. The extent of inflammatory damage was classified histologically into three categories on the basis of cell infiltration: mild (Mi), moderate (Mo), and severe (Sv). The regional count in the region of interest set on the autoradiogram was normalized on the basis of that of control rats. The ratio of total cardiac uptake to the injected dose (%ID/g x BW, where ID is injected dose and BW is body weight) was calculated by tissue counting. Expressions of glucose transporters GLUT1 and 4 were evaluated by the enzyme-labeled antibody method. RESULTS: The total cardiac uptake of DG in the acute phase of myocarditis was significantly higher than in normal control rats (3.43% +/- 0.92% vs. 0.97% +/- 0.38%; P < 0.0001); it then decreased in the chronic phase but was still higher than in the controls (1.85% +/- 0.37% vs. 0.97% +/- 0.38%; P < 0.01). The total cardiac uptake of 201Tl in the acute phase of myocarditis was significantly lower than in the controls (7.4% +/- 0.7% vs. 12.0% +/- 3.3%; P < 0.005); it then increased in the chronic phase and reached normal levels (13.0% +/- 3.3% vs. 12.0% +/- 3.3%; not significant [NS]). In the acute phase, the regional uptakes of DG in the Mi, Mo, and Sv regions were 143.1% +/- 107.9%, 169.6% +/- 59.9%, and 317.5% +/- 103.3%, respectively, whereas those of 201Tl were 88.4% +/- 31.9%, 72.1% +/- 34.6%, and 48.4% +/- 21.5%, respectively. GLUT expression was evaluated visually and classified into four grades (0, 1, 2, and 3). In the acute phase, GLUT1 expression was higher in rats in the Sv group than in the controls (2.87 vs. 0.87). GLUT4 was not expressed in the Sv areas but was found in the Mi areas. CONCLUSION: In the acute phase of autoimmune myocarditis in rats, cardiac uptake of DG was accelerated by severe inflammation. Cardiac uptake of 201Tl, on the other hand, was suppressed. Our results suggest that GLUT1 expression accelerates DG uptake by cells in areas of severe inflammation.

Animals↗
PubMed2001

Whole-body hybrid PET with 18F-FDG in the staging of non-Hodgkin's lymphoma.

UNLABELLED: PET with a double-head gamma camera (hybrid PET) is a new approach to tumor imaging with 18F-FDG. This study was conducted to clarify the feasibility of whole-body FDG hybrid PET in the staging of non-Hodgkin's lymphoma (NHL) in comparison with PET with a dedicated camera (dedicated PET) and to compare the results of both FDG studies with those of CT and 67Ga scanning as conventional imaging studies (CIS). METHODS: Thirty patients with NHL were prospectively evaluated. The results of the imaging studies regarding detection of the sites involved and staging were compared with each other and with those of the reference standard based on the final overall clinical evaluation. RESULTS: Of the total of 206 sites, whole-body FDG hybrid PET and dedicated PET detected 159 sites (77.2%) and 179 sites (86.9%), respectively. Eighteen of the 20 sites missed by hybrid PET alone consisted of lesions < 1.5 cm. Both FDG studies provided concordant staging results in all but 2 patients. CIS, on the other hand, detected 164 (79.6%) of the 206 sites, 137 of which were also detected by hybrid PET. Hybrid PET detected an additional 22 sites not found by CIS, whereas CIS detected 27 additional sites. Hybrid PET and CIS provided concordant staging results in 19 patients. Hybrid PET correctly staged NHL in 5 additional patients, whereas CIS correctly staged NHL in only 1 additional patient. CONCLUSION: Whole-body FDG hybrid PET appeared to be an accurate method of staging NHL. Despite its poorer image quality compared with dedicated PET, hybrid PET provided NHL staging results comparable with those of dedicated PET. Hybrid PET also yielded results comparable with those of CIS. However, whole-body FDG hybrid PET is currently inadequate as a single modality for staging NHL and is complementary to CT.

Adolescent↗
PubMed2001

Proton chemical shift imaging in normal pressure hydrocephalus.

BACKGROUND AND PURPOSE: Differentiation of normal pressure hydrocephalus (NPH) from other types of dementia and the selection of appropriate candidates for shunt surgery remain a clinical challenge. The aims of this study were to assess the efficacy of cerebral metabolites depicted by proton chemical shift imaging (1H-CSI) in distinguishing NPH from other dementias and to examine the relationship between metabolite changes and the outcome of shunt surgery. METHODS: 1H-CSI measurements were obtained in nine patients with clinical diagnosis of NPH; six patients with other types of dementia, including Alzheimer and Pick disease; and five control subjects. The 1H-CSI sequence consisted of a double spin-echo sequence with imaging parameters of 2000/135/4-2 (TR/TE/acquisitions). Volumes of interest were selected from a section through the lateral ventricles. The peak areas and ratios of N-acetylaspartate, creatine, choline, and lactate were calculated. In two patients, follow-up 1H-CSI and N-isopropyl (123I)-p-iodoamphetamine brain perfusion imaging were available after treatment with continuous spinal drainage. RESULTS: Lactate peaks were observed in the lateral ventricles for all patients with NPH (lactate/creatine, 0.23 +/- 0.14) but not for patients with other types of dementia or control subjects. In all cases, we noted no significant differences in the peak ratios in the voxels located at the white matter near the lateral ventricles. In one patient with NPH, intraventricular lactate disappeared and regional CBF recovered after drainage. CONCLUSION: The intraventricular lactate level may be useful in differentiating NPH from other types of dementia.

Adult↗
PubMed2001

[Outpatient chemotherapy for advanced lung cancer].

We reviewed the records of outpatient chemotherapy for advanced lung cancer in our institution. Thirty-two patients received 122 courses of cisplatin-free chemotherapy as outpatient treatments. Before outpatient treatment, every patient received the first chemotherapy as an inpatient treatment and the dose of cytotoxic drugs was reduced accordingly when side effects were judged to be untolerable. Only 1 patient needed hospitalization because of pneumonia with grade IV neutropenia. The overall response included partial responses (PR) 18%, no change (NC) 55%, progressive disease (PR) 11% and the median survival from the start of outpatient chemotherapy was 384 days. The monthly average cost of medical care per inpatient was more than three times as high as that of outpatients. Cisplatin-free chemotherapy for advanced lung cancer should be given as outpatient treatment not only to maintain the quality of life of patients, but also to restrain the total cost of medical care and to use hospital beds efficiently.

Adenocarcinoma↗
PubMed2001

[Development of a guide wire with multiple markers to aid in port-catheter system placement].

We developed a guide wire with multiple markers for use during implantation of the port-catheter system for intraarterial infusion chemotherapy. With the markers on this guide wire, the distance from the common hepatic artery to the right gastroepiploic artery can be precisely measured. From this measurement, it is possible to determine the distance from the side hole to the catheter tip; unneeded catheter can be cut off with surgical scissors. In all eight cases in which this guide wire was used, we implanted the port-catheter system in the ideal position.

Adult↗
PubMed2001

Tracer accumulation in femoral head during early phase of bone scintigraphy after renal transplantation.

UNLABELLED: Nontraumatic osteonecrosis of the femoral head (ONF) is a complication of renal transplantation. The pathogenic mechanism of ONF is thought to be an ischemic event. The purpose of this study was to investigate whether 3-phase bone scintigraphy can reveal early hemodynamic changes associated with ONF after renal transplantation. METHODS: We performed 3-phase bone scintigraphy on 19 renal allograft recipients between 3 and 9 wk after they underwent renal transplantation. Regions of interest (ROI) were assigned bilaterally in the femoral heads, diaphyses, and soft tissue. The head-to-diaphysis ratio (HD) in each phase was then calculated. RESULTS: ONF occurred in 8 femoral heads of 4 patients. Three of the 4 ONF patients had no abnormal MRI findings at the time of bone scintigraphy. In phase 1, no significant difference in HDs was observed between the ONF patients (mean HD +/- SD, 0.62 +/- 0.44) and the non-ONF patients (0.31 +/- 1.40). The difference between the mean counts for bone and soft tissue was small in both instances, and the HD had a large dispersion. In phase 2, the HDs for the ONF patients (0.70 +/- 0.27) and the non-ONF patients (1.31 +/- 0.43) were significantly different (P = 0.0005). The HD was <1.00 in all femoral heads of the ONF patients, whereas 9 non-ONF heads had an HD that was <1.00. In phase 3, the HD of the ONF patients was significantly lower than that of the non-ONF patients (ONF patients, 0.92 +/- 0.17; non-ONF patients, 1.62 +/- 0.46; P = 0.0002). CONCLUSION: All ONF patients were in the group with a low HD in phase 2, suggesting a reduction in blood flow or blood pool. Phase 2 accumulation in 3-phase bone scintigraphy can be used to estimate early hemodynamic changes in patients with ONF after renal transplantation.

Adult↗
PubMed2001

A case of papillary muscle rupture caused by acute myocardial infarction.

A 63-year-old female was admitted because of cardiogenic shock due to complete rupture of the posterior papillary muscle. The diagnosis was made by echocardiography. She was treated successfully by an emergency replacement of the mitral valve. Early diagnosis and surgical treatment are mandatory and life-saving in the case of complete papillary muscle rupture.

Coronary Angiography↗
PubMed2000

Indispensable role for TNF-alpha and IFN-gamma at the effector phase of liver injury mediated by Th1 cells specific to hepatitis B virus surface antigen.

We report the development and characterization of a novel model of severe hepatitis induced against hepatitis B virus surface Ag (HBsAg). HBsAg was successfully targeted into the liver in soluble form. Using this unique property of HBsAg, we established a liver injury model induced by HBsAg-specific Th1 cells. Severe liver injury was induced in C57BL/6 mice by injection of HBsAg together with HBsAg-specific Th1 cells. Histochemical examination demonstrated extensive necroinflammatory hepatic lesions in these animals. Application of this liver injury model to mutant or gene knockout mice enabled us to define the effector mechanisms of Th1 cells in fulminant hepatitis. When Fas-deficient lpr mice were used as recipients, a similar degree of liver injury was induced as in wild-type mice. Moreover, HBsAg-specific Th1 cells obtained from perforin-/- mice could induce severe liver injury in both wild-type and lpr mice. These results indicated that neither Fas ligand nor perforin are essential for Th1-mediated liver injury in this model. Pretreatment with anti-TNF-alpha mAb prevented liver injury, whereas severe liver injury was induced in TNF-alpha-/- mice. Moreover, IFN-gamma receptor-deficient mice were resistant to Th1-mediated liver injury. Therefore, TNF-alpha and IFN-gamma, which were produced by HBsAg-specific Th1 cells during the effector phase, appeared to be indispensable in the pathogenesis of fulminant hepatitis.

Animals↗
PubMed2000

Functional anatomical study of psychogenic amnesia.

Psychogenic amnesia is characterized by an inability to recall information already stored in the patient's memory. It is usually related to a stressful or traumatic event that cannot be explained by manifest brain damage. To examine the underlying functional disturbance of brain areas in this condition, we performed a positron emission tomography (PET) activation study on a psychogenic amnesic patient and on 12 normal control subjects. A task requiring explicit retrograde memory of faces was compared with a control task. To assess functional modifications associated with the processes of recovery, a second PET study was performed on the patient 12 months after onset. During the task, activation of the right anterior medial temporal region including the amygdala was increased in the psychogenic amnesic patient. Activation of the bilateral hippocampal regions increased only in the control subjects. During recovery, the right anterior medial temporal region became less active while the right hippocampal region became more active. Activation levels also differed in the anterior cingulate cortex, prefrontal cortex and some other cortical regions between control subjects and the patient. These findings suggest that the changes in these limbic and limbic-cortical functions are related to symptoms of the psychogenic amnesia.

Adult↗
PubMed2000

Interleukin-4-dependent induction of preproenkephalin in antigen-specific T helper-type 2 (Th2) cells.

Naive Th cells obtained from OVA(323-339)-specific DO11.10 TCR-Tg mice did not express preproenkephalin (PPE) mRNA. However, culture of naive Th cells with OVA(323-339) peptide (OVA-pep) plus IL-2 under Th2-inducing conditions for 7 days resulted in an induction of PPE mRNA. The PPE mRNA was also induced by culturing with OVA-pep plus IL-2 (neutral condition). However, PPE mRNA induction under neutral conditions was totally abrogated by addition of anti-IL-4 mAb. The existence of methionine-enkephalin was also demonstrated in peptidase-digested peptides derived from Th2 cell lysate. These results demonstrate that IL-4 is a critical factor for the induction of PPE mRNA in freshly expanded antigen-specific Th2 cells.

Animals↗
PubMed2000

Identification of a novel FGF, FGF-21, preferentially expressed in the liver.

We isolated cDNA encoding a novel FGF (210 amino acids) from mouse embryos. As this is the 21st documented FGF, we tentatively term it FGF-21. FGF-21 has a hydrophobic amino terminus ( approximately 30 amino acids), which is a typical signal sequence, and appears to be a secreted protein. The expression of FGF-21 mRNA in mouse adult tissues was examined by Northern blotting analysis. FGF-21 mRNA was most abundantly expressed in the liver, and also expressed in the thymus at lower levels. We also isolated human cDNA encoding FGF-21 (209 amino acids). Human FGF-21 is highly identical ( approximately 75% amino acid identity) to mouse FGF-21. Among human FGF family members, FGF-21 is most similar ( approximately 35% amino acid identity) to FGF-19.

Amino Acid Sequence↗
PubMed2000

Air exposure promotes fibroblast growth with increased expression of mitogen-activated protein kinase cascade.

Subepithelial tissue cell types in vivo are separated from air by the surface-covering epithelial layer of various organs, e.g., the skin, cornea, and respiratory and upper alimentary tracts. The epithelial defect caused by inflammatory, traumatic or surgical injury would be expected to expose the subepithelial tissue-localized fibroblasts to influx air. However, it is unclear what effects air stimulation elicits in fibroblast growth, which is critical for wound healing. To address this question, we examined the proliferation of 3T3 fibroblasts with bromodeoxyuridine (BrdU) uptake, using fibroblast-embedded collagen gel culture with or without air exposure. The BrdU intake of air-exposed fibroblasts was about 6 times that of air-nonexposed cells. To further characterize this fibroblast growth, we examined the expression of mitogen-activated protein kinase (MAPK) cascade, which plays a key role in the growth-signaling pathway of various cell types. Immunohistochemistry and Western blotting showed that air exposure increased MAPK cascade expression of the cells more strongly than air nonexposure. The data indicate that air exposure promotes MAPK cascade-associated fibroblast growth, suggesting in turn that in wound repair air stimulation itself may be involved in the basic mechanisms of subepithelial fibroblast proliferation and that it may be related to the pathogenesis of excessive fibroplasia through fibroblast overgrowth.

3T3 Cells↗
PubMed2000

Molecular cloning of a novel type 1 cytokine receptor similar to the common gamma chain.

In a complementary DNA (cDNA) screening of murine Th2-skewed lymphocytes with our recently developed signal sequence trap method termed SST-REX, a novel type 1 cytokine receptor, Delta1 (delta1), was identified. Although delta1 is ubiquitously expressed in multiple tissues, the expression level is higher in Th2-skewed lymphocytes than in Th1-skewed ones. The delta1 cDNA encodes a 359-amino acid type 1 membrane protein. The extracellular domain of 206 amino acids showed 24% identity with the murine common gamma receptor that is shared among the receptors for interleukin(IL)-2, IL-4, IL-7, IL-9, and IL-15. The membrane-proximal region of delta1 includes a box1 motif, which is important for association with Janus kinases (JAKs), and showed a significant homology with that of the mouse erythropoietin receptor (EPOR). A box2 motif was also found in close proximity to the box1 region. Dimerization of the cytoplasmic region of delta1 alone did not transduce proliferative signals in IL-3-dependent cell lines. However, the membrane-proximal region of delta1 could substitute for that of human EPOR in transmitting proliferative signals and activating JAK2. These results suggest that delta1 is a subunit of cytokine receptor that may be involved in multiple receptor systems and play a regulatory role in the immune system and hematopoiesis.

Amino Acid Sequence↗