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21.
Katsuaki Ukai Kazuo Terashima Yutaka Imai Haruhide Shinzawa Yoshimi Okuyama Tsuneo Takahashi Makoto Ishikawa 《Pathology international》1990,40(9):623-634
In an effort to settle the conflicting views on the proliferation kinetics of Kupffer cells (Kc), we performed 2/3 partial hepatectomy on rats injected with Pelikan ink. Using an anti-rat macrophage monoclonal antibody, ED 2, we evaluated the numerical changes in total, carbon-positive ED 2+ cells and carbon-negative ED 2+ cells in the portal and central area. We also analyzed the ultrastructure and peroxidase cytochemistry of various types of cells observed during regeneration. The total numbers of ED 2+ cells in the remaining liver increased rapidly from day 2 to 5, and the number of dividing ED 2+ cells reached a maximum on day 2. Thus, the numerical increase in ED 2+ cells corresponded to the division phase. In contrast, the carbon-labeling experiment showed a continuous increase of carbon negative ED 2+ cells from day 2 to 7. In the central area where division was less frequent, the proportion of carbon-positive cells decreased markedly to 50% on day 7, as against 97% in control rats. These findings suggest the possibility of an influx of carbon-negative Kc in addition to cell division. Ultrastructurally, the presence of carbon-negative "small Kc" and "immature Kc" with morphological features different from those of carbon-positive Kc was demonstrated. Such carbon-negative Kc with a high nucleus-to-cytoplasm ratio and rather few phagosomes, were not observed in control rats. Furthermore, we demonstrated two types of possible precursor cell, i.e. "transitional" forms between monocytes and Kc, and "immature macrophages". The former showed peroxidase activity in some lysosomes as well as in the rough endoplasmic reticulum and nuclear envelope. Our result indicated that the proliferation kinetics of Kc depend upon both local proliferation and influx. 相似文献
22.
Tsukamoto Y Yamamoto T Okado H Nibu K Terashima T 《Archives of histology and cytology》2003,66(3):209-220
The present study tested whether a gene-transfer based upon the retrograde axonal transport of the lacZ adenovirus is effective in the spinal descending tracts of the adult mouse. A small volume of a replication-defective recombinant adenovirus encoding E. coli beta-galactosidase was injected into the upper lumbar cord, and, seven days later, the mice were transcardially perfused by a fixative solution. X-gal staining of coronal or sagittal sections of the spinal cord and the brain revealed that many sites of origin for rubrospinal, vestibulospinal, and reticulospinal tracts were retrogradely labeled, whereas few of the corticospinal tract neurons were retrogradely labeled. Ependymal cells surrounding the central canal of the spinal cord, which were located far from the injection site, showed a high expression of beta-galactosidase activity. Motoneurons around the injection site were strongly stained by X-gal staining, and their axons in the ventral root were anterogradely labeled. Afferent fibers in the dorsal root were labeled by the transganglionic transport of beta-galactosidase. To examine the efficacy of the uptake and retrograde transport of HRP and adenovirus, we injected a mixed solution of 10% HRP and recombinant adenovirus. The number of HRP-labeled corticospinal neurons overwhelmed the number of X-gal stained ones, while the numbers of HRP-labeled rubrospinal and subcoeruleus-spinal neurons were smaller in comparison with the numbers of beta-galactosidase-positive counterparts. The present study revealed that the origins for the spinal descending tracts except for corticospinal neurons could be efficiently gene-transferred by the retrograde infection of a recombinant adenovirus. Such a difference in efficacy of retrograde infection among the spinal descending tracts is practically important when an adenovirus-mediated gene transfer is designed to treat certain neurological diseases affecting the spinal descending tracts. 相似文献
23.
Eiji Satoh Hirofumi Naganuma Atsushi Sasaki Mitsuyasu Nagasaka Hitoshi Ogata Hideaki Nukui 《Journal of neuro-oncology》1997,33(3):195-200
Glioblastoma cells secrete transforming growth factor- (TGF-), whichhas a variety of immunosuppressive properties. We investigatedthe effect of irradiation TGF- secretion by malignantglioma cells. Three malignant glioma cell lines (T98G,A172, KG-1-C) were cultured and irradiated using 10and 50 Gy Linac radiation. After further culturefor 36 hours in serum-free culture medium, thesupernatants were collected. The TGF- activity in theculture supernatants was determined using a specific bioassay.The levels of the active form and totalTGF- in the supernatants from irradiated malignant gliomacells decreased compared to those from un-irradiated cells.However, since irradiation inhibited the growth of tumorcells, the amount of TGF- secretion per cellin irradiated cells tended to increase after irradiation.These results suggest that malignant glioma cells canstill secrete TGF- and activate latent TGF- evenafter large dose irradiation, despite the inhibition oftumor growth. 相似文献
24.
Kunihiko Shiraki Mitsuyasu Moriwaki Muneaki Matsumoto Takeya Khono Tokuhiko Miki 《International ophthalmology》1997,21(1):43-50
Purpose. Hypofluorescent spots were seen inindocyanine green (ICG) angiography of peau dorangefundus in eyes with angioid streaks. Origin of the hypofluorescentspots were examined with attention to their correlationwith a peau dorange appearance of the central fundususing a computer-assisted image comparison system. Methods. ICG angiography was performed in 5 patientshaving peau dorange appearance of fundus using ascanning laser ophthalmoscope (SLO) and a digitalvideo-fundus camera. The same central fundus areas corresponding to hypofluorescent spots in an ICGangiogram were then digitally identified in afluorescein angiogram and in a red-free picture in all10 eyes of the 5 patients. Monochromatic lightobservation was also performed with a dark fieldobservation using a SLO to see subretinal orintrachoroidal pigment clumping. Results. In no patient, the areas identified withhypofluorescent spots did show relevant changes ina fluorescein angiogram or a red-free picture. SLOexamination revealed not perfusion defect at the sameareas. The dark field observation showed no pigmentclumping at the peripapillary and papillomacularbundle regions where hypofluorescent spots were seen.Conclusions: Hypofluorescent spots seen in ICGangiograms did not show exact consistency with peau dorange changes in their location and shape. Perfusion defects or blocking by pigments were not acause of hypofluorescent spots. The scatteredhypofluorescent spots were considered to be relevantwith irregular affinity of the fundus to ICG dye. 相似文献
25.
H Tozaki T Fujita J Komoike S I Kim H Terashima S Muranishi S Okabe A Yamamoto 《The Journal of pharmacy and pharmacology》1999,51(3):257-261
The objective of this study was to achieve colon-specific delivery of budesonide using azopolymer-coated pellets and to accelerate healing of 2,4,6-trinitrobenzenesulphonic acid sodium salt (TNBS)-induced colitis in rats. After oral administration of azopolymer-coated pellets containing budesonide, a significant increase was observed in the therapeutic effects of the drug accompanied by a decrease in its systemic adverse effects when compared with oral administration in saline or rectal administration by enema. In addition, with the use of the colon-specific oral dosage form the dose of budesonide could be reduced. These results suggested that azopolymer-coated pellets may be a useful dosage form for the colon-specific delivery of budesonide as an anti-inflammatory steroid drug to bring about the healing of TNBS-induced colitis in rats. 相似文献
26.
Terashima Keisuke Takai Satomi Usami Yoshiko Adachi Tetsuo Sugiyama Tadashi Katagiri Yoshihiro Hirano Kazuyuki 《Pharmaceutical research》1996,13(9):1327-1330
Purpose. Indomethacin is well known to be metabolized via O-demethylation and N-deacylation. In this paper we found an enzyme involved in the hydrolysis of amide-linkage of indomethacin and partially characterized it as well as its substrate specificity.
Methods. An indomethacin hydrolyzing enzyme was purified to homogeneity from pig liver microsomes using columns of Q-Sepharose, Red-Sepharose and Blue-Sepharose. The enzyme activity was assayed by measuring of -chlorobenzoic acid liberated from indomethacin by HPLC.
Results. The purified enzyme effectively hydrolyzed the amide linkage in indomethacin but not those in -naphthylacetate and -nitrophenylacetate, which are typical substrates for carboxylesterase. The subunit molecular mass of the enzyme was 65 kDa according SDS-polyacrylamide gel electrophoresis. The Michaelis constant (Km) and maximum velocity (Vmax) values for indomethacin were 67.8 µM and 9.02 nmol/min/mg protein, respectively. The amino acid sequence analysis of the enzyme after cyanogen bromide cleavage showed high homology with a mouse carboxylesterase isozyme designated as ES-male. The activity of indomethacin hydrolysis was relatively high in the pig, rabbit and human liver homogenate, but not in those from rat and mouse. On the other hand, purified human liver carboxylesterases pl 5.3 and 4.5, and pig liver carboxylesterases have no catalytic activity for indomethacin.
Conclusions. These results indicate that the hydrolysis of amide-linkage of indomethacin in humans would be associated with an enzyme similar to the indomethacin hydrolyzing enzyme from pig liver microsomes described here. 相似文献
27.
Watanabe T Mikami A Shigedo Y Motonishi M Honda H Kyotani K Uruha S Terashima K Teshima Y Sugita Y Takeda M 《Psychiatry and clinical neurosciences》2000,54(3):338-339
Severity of negative esophageal pressure (Pes) and apnea hypopnea index (AHI) were investigated in six cases of upper airway resistance syndrome (UARS) and 11 cases of obstructive sleep apnea syndrome (OSAS). The severity of negative Pes was represented by the highest peak (Pes Max) and the number of increased episodes (more than 13.5 cmH2O) per h (NPesI13.5). There was no significant correlation between Pes indices and AHI. Pes Max and NPesI13.5 were not different among severe OSAS (AHI > 30), mild OSAS (AHI < 30) and UARS. Apnea hypopnea index failed to represent the severity of negative Pes, which is an important aspect of the pathophysiology of sleep-disordered breathing. 相似文献
28.
OBJECTIVES: Decreased proprioception may contribute to the risk of falls in elderly patients. The purpose of this study is to determine whether patients with hip fractures have decreased hip proprioception compared with aged-matched controls, and whether hip proprioception differs in patients with repaired fractures compared with patients who have undergone prosthetic hip replacement after hip fracture. DESIGN: Retrospective. PATIENTS/PARTICIPANTS: Both hips of twenty-four hip fracture patients and age-matched patients without hip fractures were studied. Hip fracture patients were divided into osteosynthesis (twelve hips) and hemiarthroplasty (twelve hips) groups. INTERVENTION: Reproducibility of index angles (thirty hip flexion and thirty hip abduction) were compared with a six-degree-of-freedom electrogoniometer (instrumented spatial linkage; angular accuracy +/-0.5 degrees). RESULTS: There was no significant difference (flexion, p > 0.20; abduction, p > 0.67) in joint proprioception between fracture and no fracture groups. Likewise, there was no difference (flexion, p > 0.99, abduction; p > 0.74) in joint proprioception between osteosynthesis and hemiarthroplasty groups. CONCLUSIONS: Joint proprioception of hip fracture patients was not found to be diminished compared with age-matched normal controls. Additionally, replacement of the femoral head did not reduce joint proprioception compared with osteosynthesis with an intact femoral head. Maintenance of the femoral head does not seem to be necessary for the maintenance of joint proprioception in elderly hip fracture patients. 相似文献
29.
The human T-cell factor-4 gene splicing isoforms, Wnt signal pathway, and apoptosis in renal cell carcinoma. 总被引:4,自引:0,他引:4
30.