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41.
42.
The chronological changes in the gene expression for three species of cytosolic fatty acid-binding proteins (FABPs) in the rat brain were examined by Northern and in situ hybridization analyses. The expression for heart(H)-FABP became evident after birth, with a gradual increase and confined to the gray matter, suggesting that the expression of H-FABP mRNA is neuron-specific in postnatal brain. The expression for brain(B)-FABP was very intense in the ventricular germinal zone, without expression in the cerebellar external granule cell layer, suggesting the dominant expression in the cells of glial lineage. B-FABP mRNA was transiently expressed in perinatal gray as well as white matter and the expression in glial cells persists only in the olfactory nerve fiber layer at the adult stage. On the other hand, the expression for skin type(S)-FABP was evident in the both ventricular germinal zone and cerebellar external granule cell layer, suggesting the expression in cells of neuronal lineage. The expression for S-FABP was evident in the prenatal gray matter and S-FABP mRNA was expressed in glial cells at early postnatal stage, whereafter the expression decreased to, but remained at weak levels in the adult brain. Discrete functions of the three FABPs were suggested in neurons and glia differentially at various developmental stages. 相似文献
43.
In order to clarify morphology and function(s) of the terminal nerve, gross examinations of the nerve were carried out in 9 species of selachians. The terminal ganglion was observed light- and electron-microscopically. FMRF-amide immunoreactivity of the terminal nerve was also examined in some species. The results were as follows: 1) The terminal nerve was divided into peripheral and central branches by interposed ganglion(s). Macroscopically, the peripheral branch appeared from an area between the nasal sac and the olfactory bulb. The central branch entered the telencephalon from either the rostral, dorsal, or ventral surface. The position seemed to differ from species to species. 2) The terminal nerve showed great species differences and individual variations in the macroscopic morphology, such as number and course of the peripheral branch, position, size and number of ganglia, and telencephalic areas where the central branch entered. Even in the same individual, there was a difference in left and right sides. 3) According to general histology, the ganglion was encapsulated and had no direct connection with the telencephalon through the capsule, even when the ganglion was situated on the telencephalon. The Bodian preparations showed that most ganglion cells were unipolar, and a few were bipolar or pseudounipolar. 4) All ganglion cells and the processes were FMRF-amide immunoreactive. Immunoreactive fibers of the central branch terminated in the septal and preoptic areas. FMRF-amide immunoreactive cells were also found in the olfactory nerves or the septal area of the telencephalon in some species. These neurons were thought to be ectopic ganglion cells. 5) Neuronal somata and the axons in the ganglion contained large dense cored vesicles.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
44.
45.
Electron-dense deposition patterns and the outcomes of idiopathic membranous nephropathy in Japanese 总被引:1,自引:0,他引:1
Hitoshi Yokoyama Keiichi Yoshimoto Takashi Wada Kengo Furuichi Satoshi Goshima Hiroshi Kida Ken-ichi Kobayashi 《Medical Electron Microscopy》2002,35(2):81-86
A considerable diversity in prognosis is seen with membranous nephropathy (MN). In terms of pathological findings, the presence of tubulointerstitial lesions was emphasized as a poor prognostic factor. However, the glomerular factors affecting the long-term outcome of idiopathic human MN have remained unclear. We reviewed the initial clinicopathological factors affecting the primary and secondary outcomes in 105 patients with primary MN, as well as reviewing previous reports. Based on electron microscopic (EM) findings, we could divide patients into two subtypes and one subgroup; i.e., homogeneous type with a synchronous phase of electron-dense deposits, with large dense deposits (deep subgroup) and heterogeneous type with various phases of dense deposits. The homogeneous type showed no endstage renal failure, and had earlier remission as compared with the heterogeneous type. For the secondary outcome, heterogeneous type and deep subgroup were also independent risk factors. However, there was no significant difference in the final primary or secondary outcome for any treatment subgroups. These results indicated that our category of EM findings was a beneficial marker of the primary and secondary outcomes in MN; the homogeneous type of MN with synchronous phase of electron-dense deposits (except for the "deep" subgroup) had a good outcome. 相似文献
46.
Expression of matrix Gla protein and osteonectin mRNA by human aortic smooth muscle cells. 总被引:3,自引:0,他引:3
Hiroyuki Hao Seiichi Hirota Hatsue Ishibashi-Ueda Toshio Kushiro Katsuo Kanmatsuse Chikao Yutani 《Cardiovascular pathology》2004,13(4):195-202
BACKGROUND: Recent data indicate that matrix proteins such as matrix Gla protein (MGP) and osteonectin (ON) influence not only mineralization of vasculature but smooth muscle cell (SMC) differentiation. METHODS: We examined whether MGP and ON are expressed by human aortic SMCs in vivo using Northern blotting, in situ hybridization and immunohistochemistry. RESULTS: MGP and ON mRNAs were strongly expressed in the aorta without atherosclerosis from newborn and four young subjects up to 10 years old. In the aorta from 15 adult cases, MGP and ON mRNAs were decreased as atherosclerosis developed. We determined cell type and distribution of the MGP- and ON mRNA-expressing cells by in situ hybridization and immunohistochemistry. In the aorta obtained from newborn and young subjects, SMCs in the media and thin intima expressed MGP mRNA and, to a lesser extent, ON mRNA. In the adult aorta with fibrous thickening, MGP mRNA was expressed by intimal SMCs and subpopulation of medial SMCs. Osteonectin mRNA was expressed mainly by intimal SMCs and few medial SMCs. Double immunohistochemical staining revealed that both MGP- and ON protein-expressing cells were positive for anti-alpha-smooth muscle actin antibody, aortic SMCs. CONCLUSIONS: These results suggested that MGP and ON expression by aortic SMCs might be regulated by the degree of atherosclerosis and SMC differentiation in human aorta. 相似文献
47.
Tetsuya Yoshida Seiichi Nakai Akira Yorimoto Takashi Kawabata Taketoshi Morimoto 《European journal of applied physiology》1995,71(2-3):235-239
We measured the aerobic capacity, sweat rate and fluid intake of trained athletes during outdoor exercise and examined the relationship between aerobic capacity and thermoregulatory responses at high ambient temperatures. The maximal aerobic capacity (
) of the subjects, nine male baseball players of college age, was determined by maximal exercise tests on a cycle ergometer. The subjects practised baseball regularly without drinking fluids from 1330 to 1530 hours. After 30 min rest, they played a baseball game with free access to a sports drink at 15°C from 1600 to 1830 hours. At a mean ambient temperature of 36.7 (SEM 0.2)°C, the mean percentage of body mass loss (m
b) and increase of oral temperature (T
o) from 1330 to 1530 hours was 3.47 (SEM 0.12)% and 0.81 (SEM 0.14)°C, respectively. The sweat loss from 1330 to 1830 hours was 56.53 (SEM 1.56)ml · kg–1 of body mass (M
b) while the mean fluid consumption was 44.78 (SEM 2.39)ml · kg–1 ofm
b, with recovery of 76.08 (SEM 2.81)% of sweat loss. The
was significantly inversely correlated withm
b, fluid intake and rehydration amount, but showed no correlation withT
o. These results would suggest that at a given exercise intensity in subjects with a higher aerobic capacity body temperature is maintained with a lower sweating rate than that in subjects with a lower aerobic capacity. 相似文献
48.
Inhibition of human immunodeficiency virus replication in a human T cell line by antisense RNA expressed in the cell 总被引:2,自引:0,他引:2
49.
Akihiro Nakarna Seiichi Hirota Toshihiko Okazaki Kouichi Nagano Sunao Kawano Masatsugu Hori Yukihiko Kitamura 《Pathology international》1998,48(11):843-849
Interstitial cells of Cajal (ICC) are believed to lnitlate the basic contractile activity of the gastrointestlnal tract. Interstitial cells of Cajal express c-kit receptor tyroslne kinase and are deficient in Ws/Ws mutant rats with a small deletion of the c-kit gene . As Ws/Ws rats show remarkable bile reflux to the stomach, the contraction pressure of the pylorus was compared between Ws/Ws and control +/+ rats. The contraction pressure of the pylorus was measured using a mlcrotransducer, which was Inserted through a pln-hole in the anterlor wall of the stomach under anesthesla. The magnitude of bile reflux was estimated by measurlng the content of bile acids In the stomach. The c-kit messenger RNA-expressing cells were detected by in sltu hybrldlzatlon. Frequency and the maxlmum pressure of the contractlon were comparable between Ws/Ws and +/+ rats, but the duration of the contractlon was significantly shorter In Ws/Ws rats than In +/+ rats. The number of c-kit messenger RNA-expresslng ICC in the pylorus of Ws/Ws rats was 1.7% that of +/+ rats. The bile reflux observed in Ws/Ws rats was attributed to the decrease in the duration of the pyloric contraction, which appeared to result from the deficlency of c-kit messenger RNA-expressing ICC. 相似文献
50.
Oshitani N Hato F Kitagawa S Maeda K Higuchi K Matsumoto T Arakawa T 《International journal of molecular medicine》2003,11(1):99-104
Isolation of antigenic peptides from the MHC-groove has contributed to the understanding of T cell responses. However, these MHC-associated peptides have been isolated from various murine and human cell lines. The specific antigen responsible for the pathogenesis of inflammatory bowel disease is unknown. We examined antigenic peptides bound to the class II major histocompatibility complex (MHC) groove in human intestine by ion-trap tandem mass spectrometry equipped with online reverse-phase high performance liquid chromatography. We detected 55 parent proteins from 4 controls, 9 patients with ulcerative colitis, and 9 patients with Crohn's disease. The calculated molecular masses (m/z) of these peptides ranged from 874.4 to 2727.4, representing 10-26 amino acid residues. Fifty-one of these 55 parent proteins were exogenous proteins. Escherichia coli-, Saccharomyces cerevisiae-, and Caenorhabditis elegans-derived peptides were found frequently in patients with inflammatory bowel disease. The present results suggest that in vivo antigen processing by antigen-presenting cells and T lymphocytes in human intestine participate with exogenous antigen presentation. Increased immune responses against E. coli, S. cerevisiae and C. elegans found in patients with inflammatory bowel may participate as dysregulated immune responses to enteric flora in the pathogenesis of inflammatory bowel disease. 相似文献