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H Ueda

Publications and source records attributed to H Ueda.

At least 379 records · Page 21Linked to original sources
PubMed1997

Ultrastructural study of axonal cytoskeletons in the optic nerve damaged by acutely elevated intraocular pressure using the quick-freezing and deep-etching technique.

The aim of this study was to examine the ultrastructure of axonal cytoskeletons in guinea pig optic nerve damage induced by acutely elevated intraocular pressure (IOP) employing the quick-freezing and deep-etching method. An IOP of 60 mm Hg was maintained for 4 h. The unmyelinated axoplasm of the optic nerve at the normal IOP was filled with longitudinally oriented neurofilaments and bundled microtubules, which were cross-linked by numerous cross-bridges. Membranous organelles, such as mitochondria and vesicles, were scattered in the axoplasm. These organelles were similarly interconnected with microtubules or neurofilaments by the cross-bridges. The unmyelinated axoplasm of the optic nerve following acutely elevated IOP was shown to include intraaxonal collections of various membranous organelles and reduction of microtubules and neurofilaments. The cross-bridges linking microtubules, neurofilaments and membranous organelles in such axoplasm appeared to be dramatically reduced in number. Thus, it is suggested that the ultrastructural changes of axonal cytoskeletons in some optic nerves following elevated IOP might include the reduction of microtubules, neurofilaments and their associated cross-bridges.

Animals↗
PubMed1997

A near-infrared spectroscopic study of cerebral ischemia and ischemic tolerance in gerbils.

BACKGROUND AND PURPOSE: To explore the physiological mechanism of ischemic tolerance, we studied intracerebral oxygenation states noninvasively using near-infrared spectroscopy after bilateral common carotid artery occlusion (BCO) in gerbils with and without ischemic pretreatment. METHODS: Under ether anesthesia, gerbils with sham operation (S group, n = 8) and those with pretreatment consisting of BCO for 2 minutes, twice at 3 days and 2 days earlier (T group, n = 8), were again subjected to BCO for 5 minutes. Changes in oxyhemoglobin (HbO2), deoxyhemoglobin (Hb), and total hemoglobin (HbT) as well as reduction in cytochrome oxidase (cyt.aa3) were calculated from the absorbance changes of the light transmitted through the brain. Seven days after the ischemic study, immunohistochemical examination was performed with an antiserum against microtubule-associated proteins. RESULTS: In both groups, the increase of Hb and decrease of HbO2 and HbT proceeded rapidly after BCO, and the maximal deoxygenation of hemoglobin occurred within 2.5 minutes. Reduction of cyt.aa3 also ensued rapidly and reached the maximal reduction within 3 minutes in both groups. In the T group, however, both deoxygenation of hemoglobin and reduction of cyt.aa3 progressed more slowly than in the S group. The time (seconds) necessary for a maximal change for cyt.aa3 was significantly longer in the T group (203.8 +/- 34.0 [mean +/- SD]; P < .01) than in the S group (68.0 +/- 14.7). The time necessary for a half-maximal change was also significantly longer in the T group than in the S group for both Hb (22.0 +/- 7.5 and 13.5 +/- 4.0, respectively; P < .05) and cyt.aa3 (23.9 +/- 5.7 and 11.6 +/- 4.3; P < .01). After recirculation for 7 days, all gerbils in the S group were found to have neuronal death in the hippocampus, while those in the T group did not. CONCLUSIONS: The present study indicated that mild ischemic stress can induce improvement in oxygen metabolism during subsequent ischemia, which might be causally related to the phenomenon known as "ischemic tolerance," in which a protective effect toward ischemic/postischemic injury is induced by earlier mild ischemic pretreatment.

Animals↗
PubMed1997

Association of the gamma12 subunit of G proteins with actin filaments.

Recent studies have suggested an association between heterotrimeric G proteins, which play a major role in transmembrane signal transduction, and intracellular components. We therefore examined the subcellular localization of isoforms of G protein gamma subunits in Swiss 3T3 and C6 glioma cells, mainly containing the gamma5 and gamma12 subunits. Immunocytochemical double staining with phalloidin showed co-localization of the gamma12 subunit with actin filaments (F-actin), while the gamma5 co-localized with vinculin, suggesting an association with focal adhesion. Pretreatment of cells with Triton X-100 eliminated the gamma5 but not the gamma12 staining. Co-localization of gamma12 and F-actin was preserved when F-actin was disorganized with cytochalasin D or reorganized using fetal calf serum. Large amounts of gamma12 were recovered in the vimentin- and tubulin-free F-actin-rich fraction prepared from crude cytoskeleton preparations by double depolymerization-repolymerization. Co-localization of Gi2alpha, beta and gamma12 in the F-actin-rich fraction suggested the existence of gamma12 as a betagamma or heterotrimeric complex. Furthermore, purified betagamma12 was found to associate with F-actin in vitro more tightly than betagamma5. These results strongly suggest that the gamma12 subunit associates with F-actin in cells. The observed differential distribution of gamma12 and gamma5 implies functional differences for the two gamma subunits.

3T3 Cells↗
PubMed1997

Inhibition of tumor necrosis factor-alpha production by orally administering a perilla leaf extract.

The overproduction of tumor necrosis factor-alpha (TNF-alpha) was suppressed by orally administering a perilla leaf extract (PLE). When mice were successively injected with OK-432, severe TNF-alpha was induced in the serum, but this elevated TNF-alpha level was reduced after an oral administration of PLE (400 microliters/mouse). Oral administration of PLE also inhibited TNF-alpha production that was induced by muramyl dipeptide (500 micrograms/mouse) and OK-432 (3 KE/mouse). These characteristics were obtained from all strains of perilla. The inhibitory activity against TNF-alpha production was heat-stable, and the existence of several active molecules was suggested. When PLE was passed through an ultrafilter, the inhibitory activity against TNF-alpha production was collected in those fractions with a mass of 0.5 to 1 kDa and more than 10 kDa. When PLE was solvent-extracted, the strongest activity was recognized with aqueous preparation, although significant activity was also detected in preparations extracted with n-hexane and ethyl acetate. These findings suggest that the daily use of certain functional foods may be useful for controlling the host defense system.

Animals↗
PubMed1997

Changes in expression of neurohypophysial hormone genes during spawning migration in chum salmon, Oncorhynchus keta.

We analyzed changes in the hypothalamic levels of vasotocin (VT) and isotocin (IT) mRNA in chum salmon during spawning migration to the Ishikari river. The fish were caught at Atsuta, a fisherman's village facing the Ishikari bay, and at Chitose, an upstream branch of the Ishikari river. The former are referred to as sea water (SW) fish, and the latter as freshwater (FW) fish. The levels of VT and IT mRNA in the forebrains were determined by quantitative Northern blot analysis using single-stranded DNA with the same mRNA sequences as the standards. Levels of VT mRNA were higher in the FW males than the FW females, although no such difference was seen in the SW fish. Changes in the levels of VT mRNA were markedly different in males and females. In the males, no significant differences were seen in the levels of VT-I and VT-II mRNA between the SW and FW fish. However, in the females, the levels of VT mRNA in the FW fish were significantly lower than those in the SW fish. Changes in the levels of IT-I and IT-II mRNA were essentially similar in the males and females. These results suggest that the control of VT gene expression is different in males and females during spawning migration, although the neuroendocrine mechanism is not known.

Actins↗
PubMed1997

[Toxicity studies of landiolol hydrochloride (ONO-1101) (3). 4-week repeated dose intravenous toxicity study in dogs with 4-week recovery test].

4-week repeated dose toxicity study with 4-week recovery test of landiolol hydrochloride (ONO-1101), a novel ultra short acting beta-blocker, was conducted in beagle dogs. ONO-1101 was administered intravenously to dogs of both sexes at a dose level of 0 (control), 12.5, 25 or 50 mg/kg/day. No deaths occurred throughout the treatment period. Transitory licking chops, vomiting, nausea, diarrhea and soft feces were observed occasionally in both sexes dosed 25 and 50 mg/kg/day and the incidence seemed dose-dependent. However, those incidence declined in the course of the treatment period. Hematology showed a decrease in red blood cell count, hematocrit and hemoglobin value in both sexes receiving 25 and 50 mg/kg/day. ONO-1101 did not effect on body weight, food consumption, respiratory rate, pulse, rectal temperature, heart rate, blood pressure, electrocardiography, renal or hepatic function, ophthalmology, urinalysis, occult blood in feces, blood chemistry, organ weights, necropsy and microscopic findings at any doses. These results indicate that the no-adverse-effect level of ONO-1101 in dogs is 12.5 mg/kg/day for both sexes in this study.

Adrenergic beta-Antagonists↗
PubMed1997

[Electrophysiological study of inner ear barotrauma in guinea pigs; comparison with scanning electron microscopic findings].

To investigate the mechanism of barotrauma to the inner ear, we used electrophysiologic methods to evaluate guinea pigs exposed to such trauma, and compared the findings with those observed by scanning electron microscopy (SEM). Guinea pigs with good Preyer's reflexes were studied. In those animals that showed a loss of or decrease in Preyer's reflexes and/or nystagmus following exposure to an increase and decrease in pressures in a high-pressure chamber, we measured compound action potentials (CAPs) and cochlear microphonics (CMs) 7-11 days after the exposure. The pressure was increased from 1 ATA to 2 ATA over 30 sec and maintained for 10 min, then pressure was decreased to 1 ATA over 30 sec. Specimens obtained from animals in which CAPs and CMs could be measured were prepared for SEM examination. CAPs and CMs were measured at decreasing 5 dB increments to the visual threshold level of detection with tone bursts at 1, 2, 4 and 8 kHz. Based on the CAPs measured 7-11 days after exposure, guinea pigs were divided into two groups by CAP thresholds, those with severe damage and those with mild damage. None of the animals showed moderate damage. The group with high CAP thresholds showed severe damage to hair cells on SEM, while the group with low CAP thresholds showed no specific morphological abnormalities on SEM. It appeared that some guinea pigs with normal SEM findings following barotrauma to the inner ear did not achieve complete recovery of hearing. From these results, it was speculated that some animals had sustained reversible damage in the mild group and that these animals had recovered from moderate damage. The elevation of CMs was usually not high compared to that of CAPs in the high frequency area, and 4 animals showed CAP and CM separation above 30 dB at 8 kHz. These findings suggested that the group with severe damage exhibited multiple patterns of injury.

Action Potentials↗
PubMed1997

[Clinical efficacy of imipenem/cilastatin sodium for respiratory infections in patients with lung cancer].

Imipenem/cilastatin sodium (IPM/CS) was administered to 102 patients with respiratory tract infections and lung cancer. Patients with other serious diseases were excluded and a total of 73 patients were enrolled. They were divided into 12 patients who underwent surgery (operated group) and 61 who did not (non-operated group); the latter group included 28 patients treated with anticancer agents or radiation therapy (treated group) and 33 untreated patients (untreated group). IPM/CS was effective in 75% of the patients, both with and without surgery. The drug was effective in 81% of the treated group, although many of the patients had Stage III or more advanced cancer, as well as bronchial occlusion. IPM/CS was also effective in 69% of the untreated group, although many of the patients have serious infections and a PS (Performance Status) of 3 or greater. Thus, IPM/CS treatment achieved good results. Bacteriological studies showed that 3 out of 4 strains in the operated group and 16 out of 18 in the non-operated group were eliminated. Safety was evaluated in all patients. Two patients (2%) experienced side effects and two others (2%) showed abnormal clinical findings, but the symptoms were mild and resolved after discontinuation or completion of therapy. In conclusion, IPM/CS was very effective for treating respiratory infections in patients with lung cancer.

Adenocarcinoma↗
PubMed1997

Effect of D-(E)-2-amino-4-methyl-5-phosphono-3-pentenoic acid on ischemic brain damage induced by four-vessel occlusion in rats.

The effect of the new competitive N-methyl-D-aspartate (NMDA) antagonist D-(E)-2-amino-4-methyl-5-phosphono-3-pentenoic acid (CAS 137424-81-8, CGP 40116) was evaluated in a rat four-vessel occlusion model and compared to the effect of another NMDA antagonist (+/-)-cis-4-phosphonomethyl-piperadine-2-carboxylic acid (CAS 110347-85-8, CGS 19755) under the same conditions. Drugs were administered intravenously immediately following occlusion. At 72 h after the ischemia, latency in the passive avoidance test was significantly shorter in ischemic control rats in comparison with sham-operated rats. CGP 40116 at the dose of 10 mg/kg and CGS 19755 at the doses of 10 and 30 mg/kg significantly lengthened the latency. At 2 weeks after ischemia, ischemic control rats showed no differences in latency compared to sham-operated rats. The number of survived neurons of control rats was significantly less than that of sham-operated rats at 72 h and 2 weeks after ischemia. CGP 40116 at the doses of 3 and 10 mg/kg and CGS 19755 at the doses of 10 and 30 mg/kg significantly increased the number of survived neurons. Adenosine triphosphate (ATP) level in striatum of control rats was significantly lower than that of sham-operated rats at 24 h after ischemia when an acquisition trial was performed in the passive avoidance test. CGP 40116 at the dose of 10 mg/kg and CGS 19755 at the dose of 30 mg/kg ameliorated the decrease. These results suggest that CGP 40116 might have an ameliorative effect on the memory deficits in the passive avoidance test after ischemic injuries through the suppression of changes in brain energy metabolism.

2-Amino-5-phosphonovalerate↗
PubMed1997

Novel isoform of myotonin protein kinase: gene product of myotonic dystrophy is localized in the sarcoplasmic reticulum of skeletal muscle.

It is quite important to know the exact localization and function of myotonin protein kinase (MtPK), identified as the gene product of myotonic dystrophy, the most prevalent disease with multisystem disorders among muscular dystrophies. To investigate the localization of MtPK, we raised a polyclonal antibody against a synthetic peptide chosen within the deduced sequence of MtPK. This antibody detected both a membrane-bound 70-kd protein and a soluble 55-kd protein on Western blots of human muscles. By using this antibody for immunohistochemical studies of both biopsied human skeletal muscle fibers and mature innervated cultured muscle fibers, we can now demonstrate by confocal laser scanning microscopy that MtPK is localized mainly in the I-band. By immunoelectron microscopy, it was determined that MtPK is a membrane-bound protein localized mainly in the terminal cisternae of the sarcoplasmic reticulum. To our knowledge, this is the first documentation of the ultrastructural localization of MtPK. This finding is quite important for clarifying the pathophysiological basis of myotonic dystrophy, which might be due to a dysregulation of calcium metabolism.

Actins↗
PubMed1997

Comparison of proliferative activity in coronary plaques from patients with coronary ischemia. Histopathological and immunohistochemical analysis.

The overgrowth of cells of the vessel wall, especially of the smooth muscle cells (SMCs), contributes to the pathogenesis of coronary atherosclerosis and wound repair after coronary angioplasty. However, the association between cellular proliferation in coronary lesions and clinical pathophysiology remains to be clarified in humans. Thus, we investigated proliferative activity in coronary tissues obtained from patients with coronary ischemia. The proliferative activity in tissues obtained by using directional coronary atherectomy (DCA) from 87 coronary lesions was assessed by immunohistochemical staining for the proliferating cell nuclear antigen (PCNA). The lesions were divided into 34 primary lesions and 53 postangioplasty lesions. The 34 primary tissue samples were obtained from 9 patients with stable angina pectoris (SAP) and 25 patients with acute coronary syndromes (ACS). Collectively, the 53 postangioplasty tissue samples were obtained from 37 patients with SAP and 16 patients with ACS. The PCNA labeling index (LI) was quantified as the mean percentage of PCNA-positive cells in the 3 most positive high-power fields (x 200). The mean LIs were high in the primary ACS samples [8.9 +/- 2.1% (p = 0.01)] and postangioplasty samples [2.3 +/- 0.8% (p = 0.08) in SAP cases and 4.1 +/- 2.4% (p = 0.06) in ACS cases] compared with the primary SAP samples (0.2 +/- 0.2%). Intimal hyperplasia, a random proliferation of SMCs (alpha-actin positive) was marked in the primary ACS samples (76%) as well as in the postangioplasty SAP (92%) and ACS (81%) samples, as compared with the primary SAP samples (33%) (p < 0.01). PCNA expression was mainly evident in the nucleus of the SMCs and CD68-positive macrophages. Many PCNA-positive cells were localized in plaque areas, as follows: intimal hyperplasia, neovascularized lesions, lesions with macrophage clusters, and lesions near areas of disrupted internal elastic lamina. The levels of PCNA expression in coronary lesions were not associated with the subsequent development of restenosis after DCA. Our findings suggest that the excessive proliferation of vascular wall cells, especially SMCs, is involved in the pathogenesis of ACS and in the process of wound repair after angioplasty in humans.

Adult↗
PubMed1997

Expression of endothelial nitric oxide synthase in human eccrine clear cells.

Nitric oxide is generated from L-arginine by nitric oxide synthase (NOS), which has at least three isoforms; endothelial-type NOS (eNOS) and brain-type NOS (bNOS) are constitutive enzymes, and inducible-type NOS (iNOS) is expressed after stimulation. Studies by the avidin-biotin immunocomplex method, revealed eNOS immunoreactivity exclusively in the human eccrine clear cells. No eNOS immunoreactivity was observed in the eccrine dark cells or myoepithelial cells. No staining of iNOS or bNOS was observed in the eccrine gland. These findings indicate that NO plays a physiological part in the production and/or excretion of sweat in the human skin eccrine gland.

Adult↗
PubMed1997

Immunocytochemical study of dystrophin localization in cone cells of mouse retinas.

PURPOSE: Previously, the authors reported that dystrophin was observed under the rod cell membranes in rat retinas. However, it was not determined whether dystrophin is located in cone cells. In the current study, the authors clarify dystrophin localization in cone cells of mouse retinas. METHODS: Immunoblotting, confocal laser scanning microscopy, and immunoelectron microscopy were used to investigate retinal dystrophin with a monoclonal antibody raised against the human dystrophin C-terminus. RESULTS: Immunoblotting analysis showed some immunoreactive bands from retinal extracts. Confocal images indicated two different immunostaining patterns: One was a tiny dot, and the other was a larger, aggregated dot. Immunoelectron microscopy revealed that retinal dystrophin was localized in cone cells as well as in rod cells. CONCLUSIONS: Retinal dystrophin is a common component of cone and rod cells and probably is related to the physiological function of photoreceptor cells.

Animals↗
PubMed1997

Neuroprotective effect of D-(E)-2-amino-4-methyl-5-phosphono-3-pentenoic acid in the gerbil model of transient global cerebral ischemia.

Effect of the new competitive N-methyl-D-aspartate (NMDA) antagonist D-(E)-2-amino-4-methyl-5-phosphono-3-pentenoic acid (CAS 137424-81-8, CGP 40116) was examined in a mongolian gerbil model of global cerebral ischemia. Effect of CGP 40116 was compared to that of another competitive NMDA antagonist, (+/-)-cis-4-phosphonomethyl-piperadine-2-carboxylic acid (CAS 110347-85-8, CGS 19755) under the same conditions. Drugs were administered intraperitoneally 30 min before bilateral carotid artery occlusion. At 4 days after the ischemia, locomotor activity was significantly higher in ischemic control mongolian gerbils in comparison with sham-operated mongolian gerbils. CGP 40116 at the dose of 10 mg/kg and CGS 19755 at the doses of 10 and 30 mg/kg significantly suppressed the increase of the motility. Seven days after ischemia, ischemic control group was still hyperactive compared to sham-operated group. CGP 40116 at the dose of 10 mg/kg and CGS 19755 at the dose of 30 mg/kg significantly reversed it. The number of survived neurons of ischemic control group was significantly less than that of sham-operated group at 7 days after ischemia. CGP 40116 at the dose of 10 mg/kg and CGS 19755 at the dose of 30 mg/kg significantly increased the number of survived neurons. It is concluded that CGP 40116 is more potent for amelioration of global cerebral ischemic damage than CGS 19755.

2-Amino-5-phosphonovalerate↗
PubMed1997

Effect of D-(E)-2-amino-4-methyl-5-phosphono-3-pentenoic acid on focal cerebral ischemia in cat.

The effect of the new competitive N-methyl-D-aspartate (NMDA) antagonist D-(E)-2-amino-4-methyl-5-phosphono-3-pentenoic acid (CAS 137424-81-8, CGP 40116) was examined in a cat model of focal cerebral ischemia. Effect of CGP 40116 was compared to that of another competitive NMDA antagonist, (+/-)-cis-4-phosphonomethyl-piperadine-2-carboxylic acid (CAS 110347-85-8, CGS 19755) under the same conditions. Drugs were administered intravenously 30 min before left middle cerebral artery (MCA) occlusion. After MCA occlusion for 8 h, infarction spreaded widely among caudate nucleus prepyriform cortex, amygdala and temporal lobe cortex in the ischemic hemisphere. CGP 40116 at the dose of 10 mg/kg and CGS 19755 at the dose of 30 mg/kg significantly decreased the infarcted area. CGP 40116 was effective in the frontal and central brain, although CGS 19755 showed neuroprotective effect in almost all sites. Thus, the compounds are potent neuroprotectants in focal ischemia.

2-Amino-5-phosphonovalerate↗
PubMed1997

[Effect on 5'-deoxy-5-fluorouridine (5'-DFUR) of pyrimidine nucleoside phosphorylase (PyNPase), matrix metalloprotease and serum IAP values. Hokuriku Colorectal Cancer Chemotherapy Study Group].

PyNPase activity, MMPs activity and serum IAP values were measured in tumor tissues from colorectal cancer patients who had been divided into two groups, one given preoperative 5'-DFUR and the controls. PyNPase activity of the preoperative administration group was approximately equivalent to that of the controls. In the control group, correlations were assessed between PyNPase activity and activities of MMP1 and MMP3. To assess the effect of 5'-DFUR on the activity of MMPs, we divided patients into two groups, a high and a low PyNPase activity group. Although there was no correlation with MMPs activity of the preoperative administration group and the control group in the low PyNPase activity group, the activities of MMP1 and MMP9 of the control group were significantly higher in the high PyNPase activity group. Moreover, the serum IAP value of the administration group was significantly lower than that of the control group. These results indicated that PyNPase activity was thus suggested to be somehow related to MMPs activity and serum IAP values.

Adult↗
PubMed1997

[Ureteral cancer producing carbohydrate antigen 19-9: report of a case].

A case of a CA19-9-producing ureteral cancer is reported. A 58-year-old man presented with gross hematuria. Retrograde pyelography showed an irregular filling defect in the right ureter. The serum CA19-9 level was 932 U/ml (normal < 37). Right total nephroureterectomy was performed. The histological diagnosis was grade 3 transitional cell carcinoma. Immunohistochemical analysis showed CA19-9 to be expressed not only in the cancer cells but also in the normal transitional cell epithelium of the renal pelvis.

Biomarkers, Tumor↗