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51.
Preferential expression of RB1-inducible coiled-coil 1 in terminal differentiated musculoskeletal cells
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RB1-inducible coiled-coil 1 (RB1CC1) is a nuclear DNA-binding protein that can induce RB1 (retinoblastoma 1) expression. RB1CC1 is abundantly expressed in human musculoskeletal and cultured osteosarcoma cells. The present study analyzed the expression of RB1CC1 and RB1 in osteosarcoma cells and in musculoskeletal cells of human embryos to evaluate the contribution of both genes to the maturational process of musculoskeletal cells. The amount of RB1CC1 message was closely related to RB1 expression in various osteosarcoma cell lines. RB1CC1 expression was difficult to detect in immature proliferating chondroblasts or myogenic cells in human embryos, but became obvious and prominent concomitantly with the maturation of osteocytes, chondrocytes, and skeletal muscle cells. RB1CC1 expression in these musculoskeletal cells increased with RB1 expression, which is linked to the terminal differentiation of many tissues and cells. In addition, the introduction of wild-type RB1CC1 decreased the formation of macroscopic colonies in the cell growth assay. Accordingly, both RB1CC1 and RB1 genes preferentially co-expressed and contributed to the maturation of human embryonic musculoskeletal cells, and may regulate the proliferative activity and maturation of tumor cells derived from these tissues. 相似文献
52.
Hirota M Nozawa F Okabe A Shibata M Kuwata K Ogawa M 《Rinsho byori. The Japanese journal of clinical pathology》2000,48(6):527-532
Relationship between SIRS and CARS in the pathologic condition of acute pancreatitis was discussed. SIRS promotes excessive inflammatory reaction and CARS induces the susceptibility to infection. Both conditions can develop into organ failure in acute pancreatitis. Hence, countermeasures for both conditions are mandatory in the care of patients with acute pancreatitis. 相似文献
53.
Matsuzaki Y Sato K Sugawara K Takashita E Muraki Y Morishita T Kumagai N Suzuki S Hongo S 《Journal of clinical microbiology》2005,43(2):993-995
An influenza C virus was isolated from a Japanese traveler who had visited Malaysia in April 1999. Phylogenetic analysis indicated that the genome composition of this virus was distinct from that of any other strain isolated in Japan. The possibility that a genetically unique influenza C virus was introduced into Japan by a traveler is shown. 相似文献
54.
Gondo S Yanase T Okabe T Tanaka T Morinaga H Nomura M Goto K Nawata H 《Genes to cells : devoted to molecular & cellular mechanisms》2004,9(12):1239-1247
Bone marrow stem cells develop into haematopoietic and mesenchymal lineages, but have not been known to participate in steroidogenic cell production. Steroidogenic factor 1 (SF-1), also designated adrenal 4 binding protein (Ad4BP), is an essential orphan nuclear receptor for steroidogenesis as well as for adrenal and gonadal gland development. In the present study, we revealed that the adenovirus-mediated forced expression of SF-1 can transform cultured primary long-term cultured bone marrow cells into steroidogenic cells, showing the de novo synthesis of multiple steroid hormones in response to adrenocorticotropic hormone (ACTH). This finding may provide an initial step in innovative autograft cell transfer therapy for steroid hormone deficiencies. 相似文献
55.
Neurotoxicity of Clostridium perfringens Epsilon-Toxin for the Rat Hippocampus via the Glutamatergic System
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Osamu Miyamoto Junzaburo Minami Tetsuhiko Toyoshima Takehiro Nakamura Tetsuya Masada Seigo Nagao Tetsuro Negi Toshifumi Itano Akinobu Okabe 《Infection and immunity》1998,66(6):2501-2508
The neurotoxicity of epsilon-toxin, one of the major lethal toxins produced by Clostridium perfringens type B, was studied by histological examination of the rat brain. When the toxin was injected intravenously at a lethal dose (100 ng/kg), neuronal damage was observed in many areas of the brain. Injection of the toxin at a sublethal dose (50 ng/kg) caused neuronal damage predominantly in the hippocampus: pyramidal cells in the hippocampus showed marked shrinkage and karyopyknosis, or so-called dark cells. The dark cells lost the immunoreactivity to microtubule-associated protein-2, a postsynaptic somal and dendric marker, while acetylcholinesterase-positive fibers were not affected. Timm’s zinc staining revealed that zinc ions were depleted in the mossy layers of the CA3 subfield containing glutamate as a synaptic transmitter. The cerebral blood flow in the hippocampus was not altered significantly before or after administration of the toxin, as measured by laser-Doppler flowmetry, excluding the possibility that the observed histological change was due to a secondary effect of ischemia in the hippocampus. Prior injection of either a glutamate release inhibitor or a glutamate receptor antagonist protected the hippocampus from the neuronal damage caused by epsilon-toxin. These results suggest that epsilon-toxin acts on the glutamatergic system and evokes excessive release of glutamate, leading to neuronal damage. 相似文献
56.
Kishichiro Watanabe Akio Mukawa Katsuhiko Saito Isao Nakanishi Hironobu Tsuda 《Pathology international》1986,36(12):1921-1929
An autopsy case of a 62-year-old woman with a poorly differentiated, aggressive form of adenoid squamous cell carcinoma arising in the skin overlying the right breast was studied. The tumor, 9×8cm in diameter, had rapidly enlarged since one year before admission from a verrucous lesion of 20 years duration. The histologic features of the tumor showed a well-differentiated squamous cell carcinoma mainly in the superficial areas, which transformed into, with a zone of transition in between, an alveolar or adenoid structure in the deep invading portion. The adenoid tumor cells exhibited an undifferentiated appearance with prominent nucleoli and frequent mitotic figures. These cells partly showed dyskeratotic or acantholytic features. Mucin was negative. The patient died at 8 months after the operation. Autopsy revealed widely spreading metastases in which an adenoid structure was outstanding. These unusual pathological features and an aggressive behavior of this tumor, which were hitherto rarely described for adenoid squamous cell carcinoma, seemed to be a poorly differentiated variant of the tumor. This malignant transformation might be derived from loss of cohesion of the pre-existing usual well-differentiated squamous cell carcinoma in the basal and parabasal layers, inparting marked invasiveness of these cells into the supporting connective tissue. 相似文献
57.
Masato Tsukahara Takahiro Okabe Morimasa Ohtsuka Susumu Furukawa 《American journal of medical genetics. Part A》1995,57(3):444-446
We report on an 8-year-old Japanese boy with Setleis syndrome. The patient had a very characteristic “coarse” facial appearance, bitemporal “forceps marks,” skin aplasia, sparse hair, and skin hypo- and hy-perpigmentation. He also had previously undescribed manifestations, including an aberrant hair pattern of the forehead, linear skin lesions on the forehead, short palpebral fissures, a small skin tag on the right cheek, cone-shaped teeth, and pectus carinatum. Dermatoglyphic studies documented aberrant distal palmar creases (simian crease variant), 8 arches, and reduced total finger ridge count. When serial photographs were reviewed, his facial characteristics became more obvious with increasing age. © 1995 Wiley-Liss, Inc. 相似文献
58.
Effects of ruthenium red on membrane ionic currents in urinary bladder smooth muscle cells of the guinea-pig 总被引:2,自引:0,他引:2
Masaru Hirano Y. Imaizumi Katsuhiko Muraki A. Yamada Minoru Watanabe 《Pflügers Archiv : European journal of physiology》1998,435(5):645-653
Three major ionic currents, Ca2+-dependent K+ current (I
K-Ca), delayed rectifier type K+ current (I
kd) and Ca2+ current (I
Ca), were activated by depolarization under whole-cell clamp in single smooth muscle cells isolated from guinea-pig urinary
bladder. Externally applied ruthenium red (RuR) reduced the amplitude of I
K-Ca and I
Ca at 0 mV (IC50 values were 4.2 and 5.6 μM, respectively), but did not affect I
Kd. Spontaneous transient outward currents (STOCs) and caffeine-induced outward currents (I
caf) at –30 mV were reduced by external 10 μM RuR. When 10 μM RuR was added to the pipette solution, I
K-Ca during depolarization, STOCs and I
caf significantly decreased with time. RuR did not change the unitary current amplitude of the large-conductance Ca2+-dependent K+ (BK) channels, but reduced the open probability of the channel under excised patch-clamp recording mode. RuR reduced the
channel activity more effectively from the cytosolic face than from the other. This inhibition decreased when the cytosolic
Ca2+ concentration was increased. These results indicate that RuR blocks BK and Ca2+ channels in urinary bladder smooth muscle cells. The decrease in I
K-Ca, STOCs and I
caf by RuR is attributable to the direct inhibition of BK channel activity, probably in addition to the inhibition of Ca2+ release from storage sites. The direct inhibition of BK channel activity by RuR may be related to the interaction of RuR
with the Ca2+-binding sites of the channel protein.
Received: 15 October 1997 / Received after revision and accepted: 25 November 1997 相似文献
59.
Katsuhiko Aoyama Kazuo Terashima Yutaka Imai Noriko Katsushima Yoshio Okuyama Katsuhisa Niikawa Takeo Mukada Katsuro Takahashi 《Pathology international》1984,34(2):375-388
The present paper deals with immunohistochemical and ultrastructural study of the lymph nodes of sinus histiocytosis with massive lymphadenopathy (Rosai and Dorfman, SHML) of a 12-year-old Japanese boy. This is the fourth case in Japan. Osseous manifestation was also found in the bilateral ulnae. With hallmarks of S-100 protein and interdigitating cytoplasmic extensions, the phagocytizing histiocytes proliferating in the sinuses were considered to be derived mostly from interdigitating cells in the paracortex or T cell dependent area, which have heretofore been regarded as nonphagocytizing. Furthermore, it is most interesting that lymphoid cells bearing thymic cortical cell-antigen (OKT 6) were increasingly recognized in the patient's peripheral blood. These results suggested that SHML is a specialized reactive histiocytosis analogous to histiocytosis X and histiocytic medullary reticulosis. 相似文献
60.