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71.
Expression of membrane-bound and soluble receptor activator of NF-kappaB ligand (RANKL) in human T cells 总被引:1,自引:0,他引:1
The receptor activator of NF-kappaB ligand (RANKL) and its receptor RANK are critical regulators for immune responses as well as bone remodeling. RANKL is a type II transmembrane protein that has two forms-a membrane-anchored protein and a secreted protein. In this report, we demonstrate for the first time the kinetical expression of two forms of RANKL in human T cells using two monoclonal antibodies (mAbs) against human RANKL, which we newly derived. Freshly isolated T cells rarely expressed mRANKL, while the activation of T cells induced a substantial but minimal level of mRANKL as well as the accumulation of considerable amounts of sRANKL. The addition of the metalloprotease inhibitor KB-R8301 efficiently suppressed the release of sRANKL from activated T cells or RANKL-transfectants, and reciprocally enhanced the mRANKL expression. The membrane form of RANKL was also expressed on the infiltrating T cells in the rheumatoid synovial fluid and in the gingival tissues of patients with periodontitis. Our results demonstrate that the expression of mRANKL on T cells is strictly limited, and the majority of RANKL protein produced by T cells may be active in the soluble form after shedding. The mAbs that were derived in this study may be useful for investigating the regulation and function of RANKL in immune responses and bone remodeling. 相似文献
72.
Photoreceptor differentiation of retinoblastoma: An electron microscopic study of 29 retinoblastomas
Yasuo Tajima Shigeru Munakata Yasuo Ishida Tohru Nakajima Isamu Sugano Koichi Nagao Kensei Minoda Yoichiro Kondo 《Pathology international》1994,44(12):837-843
Retinoblastomas exhibit a unique form of differentiation to produce cell elements similar to those seen in a photoreceptor cell. An ultrastructural study was performed on 29 cases of retinoblastoma to further clarify the cytologic characteristics of the tumor cells. The age of the retinoblastomas averaged 17.1 months and the tumor cells showing photo-receptor differentiation were demonstrated in 10 cases (35%). The findings were especially notable in retinoblastomas with Flexner-Wintersteiner rosette formation (seven cases, 28%). Similar photoreceptor differentiation was also evident in solid cell clusters without rosette formation (four cases, 14%). The presence of photoreceptor elements was assumed to be significantly frequent both in Flexner-Wintersteiner rosettes and in the solid cell clusters. The cell cytoplasm also showed proliferation of long mitochondria and microtubules, reflecting photoreceptor differentiation. The hereditary-type retinoblastoma showed more advanced cell differentiation than the non-hereditary type. Photoreceptor differentiated retinoblastoma showed rather indolent growth compared with the undifferentiated type, and the former can expect a curative treatment by operation. These observations provide additional findings of the biological nature of retinoblastomas. 相似文献
73.
Yuki Tajika Tohru Murakami Mahito Sato Fumitaka Kubota Hiroshi Yorifuji 《Developmental dynamics》2008,237(7):1886-1892
Vesicle-associated membrane protein 2 (VAMP2) is a member of the SNARE family of proteins that regulate the intracellular vesicle fusion process. This study investigated the developmental expression of VAMP2 in the rat embryo. In the trunk, VAMP2 was primarily found in the heart on embryonic day (E) 10. On E12.5, VAMP2 expression was found in nerve fibers, somites, and heart. In somites, epithelial cells in the dorsomedial lip, and elongated myoblasts in myotome were positive for VAMP2. On E16.5, VAMP2 was expressed in the heart, nerve fibers, and skeletal muscles. In skeletal muscles, multinuclear myotubes were positive for VAMP2. In the head, where muscles are derived both from somitic and non-somitic origin, VAMP2 was found in myotubes of the extrinsic ocular muscles and masseter muscle on E16.5. These findings suggest the involvement of VAMP2 in the development of skeletal muscles of somitic and non-somitic origins. 相似文献
74.
Shinichi Izuchi Tohru Terachi Masahiro Sakamoto Tetsuo Mikami Mamoru Sugita 《Current genetics》1990,18(3):239-243
Summary The nucleotide sequences of tRNAAsn (GUU) and tRNATyr (GUA) genes from tomato mitochondria and their flanking regions have been determined. The tomato mitochondrial tRNAAsn gene is located 2.1 kb downstream from the tRNACys gene reported previously (Izuchi and Sugita 1989) and shows a nearly complete identity with the corresponding chloroplast gene. The tRNATyr gene, which shows only 73% homology with the corresponding chloroplast gene, has to be considered a native mitochondrial tRNA gene and is 535 bp from the chloroplast-like tRNAAsn gene on the same strand. Northern hybridization analysis revealed that the three tRNA genes are transcribed in tomato mitochondria. Southern hybridization analysis of tomato, sugar beet, rice and wheat mitochondrial DNAs, with oligonucleotide probes for mitochondrial or chloroplast tRNA genes, demonstrated that the mitochondrial tRNACys gene found in tomato is present in dicot plants but not in monocots. On the other hand, a chloroplast-like tRNACys gene exists in monocot plants. 相似文献
75.
Twenty-five patients who required mechanical ventilatory support (MVS) after major surgery or severe burns were studied to determine whether airway occlusion pressure (P0.1) is a clinically useful indicator to predict the success or failure of the weaning trial. A total of 33 weaning trials were attempted on these patients. Of the 33 trials, 24 were followed by successful weaning and 9 by failure. Although the success group, when compared with the failure group, had a lower respiratory rate (P 0.001), a lower minute ventilation (P 0.001), a higher maximal voluntary ventilation to minute ventilation ratio (P 0.01) and a higher forced vital capacity (P 0.05), no threshold values separated the success from the failure group. The alveolar-arterial PO
2 gradient, with an Fi
O
2 of 1.0, in weaning success and failure showed no statistical difference. In contrast, all patients in the success group had a P0.1 of less than 3.5cmH2O and those in the failure group had a P0.1 of greater than 3.5cmH2O (P 0.001). We conclude that P0.1 is a clinically superior indicator for discontinuing MVS in patients with acute respiratory failure.(Okamoto K, Sato T, Morioka T: Airway occlusion pressure (P0.1)—A useful predictor for the weaning outcome in patients with acute respiratory failure—. J Anesth 4: 95–101, 1990) 相似文献
76.
We evaluated the reliability of conventional weaning criteria from a ventilator during 33 weaning trials on 25 patients with acute respiratory failure (ARF). Of 13 criteria, a ratio of maximal voluntary ventilation to minute ventilation (MV) 2, a vital capacity 12ml·kg–1, a spontaneous respiratory rate 25 breaths·min–1, and a MV 10l·min–1 appeared to be useful for predicting successful weaning outcome. However, even using those criteria, there were many falsely-negative cases. The alveolar-arterial PO
2 gradient 350mmHg at an Fi
O
2 1.0 was not useful as a predictor of weaning outcome. The present study demonstrates that conventional criteria are frequently inaccurate for predicting weaning outcomes and suggests that the use of some of these criteria may unnecessarily prolong the length of ventilator support. Since ventilation of most patients with poor oxygenation can be successfully discontinued by placing them on a continuous positive airway pressure system, these results suggest that the improvement of oxygenation is not an indispensable prerequisite for weaning from mechanical ventilators.(Okamoto K, Iwamasa H, Dogomori H, et al.: Evaluation of conventional weaning criteria in patients with acute respiratory failure. J Anesth 4: 213–218, 1990) 相似文献
77.
Sakuragi T Fujiwara K Akashi-Tanaka S Tsuda H Fukutomi T 《Breast cancer (Tokyo, Japan)》1997,4(1):53-56
Dermatofibrosarcoma protuberans (DFSP) is a slow-growing but locally aggressive, fibrous tumor that has a high rate of local
recurrence after surgical resection. This tumor occurs most commonly in the trunk and proximal extremities. In this report
we present a case of dermatofibrosarcoma protuberans in the skin over the breast which was re-excised after pathological diagnosis,
considering cosmetic aspects. Only three other cases of dermatofibrosarcoma protuberans of the anterior chest wall have been
encountered in our hospital, and all of these cases were male. The presence of this tumor in the skin over the breast appears
to be rare in females. Careful complete resection is recommended for this type of tumor. 相似文献
78.
Motomaru Masutani Akira Mizoguchi Tohru Arii Tadaaki Iwasaki Chizuka Ide 《Journal of neurocytology》1994,23(12):811-819
Summary The localization of protein kinase C (PKC) , and subspecies in sensory axon terminals of muscle spindles in the plantar lumbrical muscles of rat was investigated by light and electron microscopic immunocytochemistry using monoclonal and polyclonal antibodies. Immunoreactivity for these subspecies was detected specifically in sensory axon terminals which wound spirally around the intrafusal muscle fibres of the muscle spindle. Immunostaining was found to be stronger with polyclonal than with monoclonal antibodies. By electron microscopy, immunoreactivity for , and subspecies was almost diffusely distributed in the cytoplasm of the axon terminal, and the overall pattern of distribution of immunoreactivity was similar for all three subspecies. In the cases of a and subspecies, some intensely immunostained regions were found in the cytoplasm, but no definite subcellular structures corresponding to such regions could be identified. Considering that PKC plays a crucial role in the regulation of ion channels, it is suggested that PKC might be involved in the control of mechanoelectric transduction in sensory axon terminals. 相似文献
79.
Shiomi H Hase T Matsuno S Izumi M Tatsuta T Ito F Kishida A Tani T Kodama M 《Surgery today》1999,29(12):1280-1284
An 18-year-old male was admitted to our Emergency Department with a traumatic abdominal wall hernia (TAWH) of the left lower
quadrant (LLQ) after suffering hypogastric blunt injury and urogenital lacerations in a motorcycle accident. Upright chest
X-ray showed a small amount of right infradiaphragmatic free air, and a computed tomographic (CT) scan demonstrated an abdominal
wall hernia. At surgery, no impairment was found in the digestive tract, and an abdominal herniorrhaphy was performed. It
is suggested that the free air had passed through a connection between the scrotal laceration and the contralateral abdominal
defect via the subcutaneous space and was palpated as emphysema. This is a new type of TAWH, which suggests that blunt abdominal
trauma may result in negative pressure in the subcutaneous and peritoneal cavity, and this could reflect the pathophysiology
of TAWH. 相似文献
80.
Tohru Ide Tetsuo Kochi Kazuhiko Iijima Tadanobu Mizuguchi 《Journal canadien d'anesthésie》1996,43(1):44-49