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131.
Arpp,a new homolog of carp,is preferentially expressed in type 1 skeletal muscle fibers and is markedly induced by denervation 总被引:3,自引:0,他引:3
Tsukamoto Y Senda T Nakano T Nakada C Hida T Ishiguro N Kondo G Baba T Sato K Osaki M Mori S Ito H Moriyama M 《Laboratory investigation; a journal of technical methods and pathology》2002,82(5):645-655
In this study, we isolated and characterized a murine counterpart of the human Arpp (hArpp) gene. Sequence analysis revealed that the murine Arpp (mArpp) gene is almost identical to the Ankrd2 gene, which has recently been isolated as a mouse gene induced in stretched skeletal muscle. The mArpp gene encodes a protein of 332 amino acids that contains four well-conserved ankyrin-repeat domains in the central portion of the protein. The amino acid sequence of mArpp protein (mArpp) is highly homologous to that of mouse cardiac-restricted ankyrin-repeat protein (Carp), which is proposed to be a putative genetic marker for cardiac hypertrophy. Immunohistochemical analysis revealed that mArpp is preferentially expressed in type 1 skeletal muscle fibers, and that mArpp is localized in both the nucleus and the sarcomeric I-band of muscle fibers, suggesting that Arpp may function as a nuclear and sarcomeric protein. Furthermore, mArpp was also expressed in neurons of the cerebellum and cerebrum, the islets of Langerhans in the pancreas, and the esophageal epithelium, suggesting that mArpp may play a functional physiologic role in brain, pancreas, and esophagus as well as in type 1 muscle fibers. Interestingly, although mArpp was localized in both nucleus and cytoplasm in neurons, its localization was restricted to nucleus in pancreas and esophagus, suggesting that intracellular localization of mArpp is regulated in a tissue-specific manner. Furthermore, we found that mArpp- and Carp-expression in skeletal muscle were markedly up-regulated after denervation. Although the elevated expression level of Carp was kept only for two weeks after denervation, that of Arpp was kept at least for 4 weeks, suggesting that mArpp and Carp may play distinct functional roles in denervated skeletal muscle. 相似文献
132.
Toshihiko Sato Kaoru Abe Akira Kurose Noriyuku Uesugi Takeshi Todorokl and Kohsuke Sasakl 《Pathology international》1997,47(2-3):179-182
The amplification and overexpression of the c- erbB -2 gene are considered to be Implicated In the process of carcincogenesis of a variety of human tumors. The amplification and overexpression of c- erbB -2 were investigated in 48 surgically resected human gastric cancers by means of fluorescence In situ hybridization and immunohistochemistry. DNA ploidy was determined by flow cytometry. The c- erbB -2 amplification was demonstrated as a cluster of signals, suggesting homogeneously staining region (HSR), in three tumors (6.3%) accompanied by the overexpression of its protein. Such overexpression was detected In another tumor without amplification of the c- erbB -2 gene. All tumors with amplification and overexpression of c- erbB -2 were differentiated adenocarcinoma histologically, but only 10.3 and 13.8% of differentiated carcinomas showed amplification and over-expression of the c- erbB -2 gene, respectively. There was no relationship between the amplification and overexpression of c- erbB -2 and the depth of tumor invaslon and lymph node Involvement. Three of four cases with overexpression of c- erbB -2 were classified Into DNA aneupldd tumor. 相似文献
133.
Yutaka Imai Takashi Sato Mitsunori Yamakawa Takeshi Kasajima Akio Suda Yoshihiro Watanabe 《Pathology international》1989,39(2):127-134
Rheumatoid arthritis (RA) is one of the immune complex (IC) diseases in which lymphoid germinal centers (GCs) are found in the synovial tissue. Simultaneously, patients with RA often show swelling of lymph nodes. The morphology and function of the lymph node GCs in patients with RA is not clear. The aim of this study was to evaluate the differences in morphology and immunoreactions to complement (C) components, their receptors, and lgM-rheumatoid factor (RF) between synovial GCs and lymph-node GCs in RA. Furthermore, the relationship between these immuno-reactive substances and follicular dendritic cells (FDCs) in GCs was investigated. The tissues examined were 41 RA synovial specimens, seven RA lymph nodes with massive lymphadenopathy, and 10 non-RA lymph nodes. The number of synovial GCs was relatively decreased in comparison with lymph-node GCs in RA, and the diameter of each synovial GC was smaller than that of each lymph-node GC. The synovial GCs were edematous and less cellular, and moreover, those from RF-seronegative cases were smaller than those from RF seropositive cases. On the other hand, the lymph-node GCs in RA were larger, more cellular and hyperplastic, but contained more tingible-body macro-phages (TBMs) and neutrophils. In the GCs of both synovial tissues and lymph nodes in RA, early C components (C1q, C4, C3c, C3d), IgM RF, and C3b receptor (C3bR) and C3d receptor (C3dR) were expressed as a lacy network by light microscopy, and were demonstrated on the surfaces of FDCs and lymphocytes, and in the intercellular spaces by electron microscopy. Furthermore, immuno-staining for dendritic reticulum cells (DRC, DAKO DRC1) was observed in a lacy pattern by light microscopy and on the cell surface of FDCs by electron microscopy. In the GCs of non-RA lymph nodes, early C components, C3bR, C3dR, and DRC showed a similar reaction pattern, but IgMRF did not. Consequently, no marked difference in immunoreactions in the GCs, except for the immunoreactions of late C components, was found between synovial tissues and lymph nodes in RA. On the basis of these findings, we discuss the possibility of the presence of a RF-IC. 相似文献
134.
Immunohistochemical,ultrastructural and biochemical studies of an amylase-producing breast carcinoma
Hideo Inaji Hiroki Koyama Masahiko Higashiyama Shinzaburo Noguchi Hitoshi Yamamoto Osamu Ishikawa Kaoru Omichi Takeshi Iwanaga Akira Wada 《Virchows Archiv : an international journal of pathology》1991,419(1):29-33
Summary We describe a breast cancer with ectopic production of amylase, found in the patient's serum, urine and in the tumour. Clinically, serum amylase levels reflected both the progression of the disease and regression induced by various therapies. Using agarose gel electrophoresis and a wheat protein inhibitor assay, the predominant serum amylase appeared to be identical to pancreatic-type isoenzyme. However, the action mode analysis using a new fluorogenic substrate revealed that the serum contained non-salivary, non-pancreatic amylase. The tumour had microscopic features of invasive ductal carcinoma with some argyrophilic differentiation. The component cells stained positively for amylase, and ultrastructurally numerous secretory granules were seen. 相似文献
135.
In an attempt to clarify the cytological characteristics of the RES cells in the lymph nodes and their embryological correlations, lymph nodes and lymph node anlages of germ-free rats, nude mice, and human fetuses were light and electron microscopically examined. On the basis of differences of intracellular organelles, their behaviors for reticulum fibers and of endogenous peroxidatic activity, histiocytes should be reasonably distinguished from the cells conventionally called reticulum cells. Reticulum cells and histiocytes respectively are destined to differentiate in different directions from the early stage of development of the lymph node anlage. Sinus endothelial cells are ontogenetically originated and differentiated from the endothelial lining cells of lymphatic vessels. Primitive reticular cells are differentiated into mature reticulum cells in the lymph nodes, they transform into the lympho-reticular cells, further into lymphoblasts, and finally develop into medium-sized lymphocytes. 相似文献
136.
Daiyasu H Ishikawa T Kuma K Iwai S Todo T Toh H 《Genes to cells : devoted to molecular & cellular mechanisms》2004,9(5):479-495
A new type of cryptochrome, CRY-DASH, has been recently identified. The CRY-DASH proteins constitute the fifth subfamily of the photolyase/cryptochrome family. CRY-DASHs have been identified from Synechocystis sp. PCC 6803, Vibrio cholerae, and Arabidopsis thaliana. The Synechocystis CRY-DASH was the first cryptochrome identified from bacteria, and its biochemical features and tertiary structure have been extensively investigated. To determine how broadly the subfamily is distributed within living organisms, we searched for new CRY-DASH candidates within several databases. We found five sequences as new CRY-DASH candidates, which are derived from four marine bacteria and Neurospora crassa. We also found many CRY-DASH candidates from the EST databases, which included sequences from fish and amphibians. We cloned and sequenced the cDNAs of the zebrafish and Xenopus laevis candidates, based on the EST sequences. The proteins encoded by the two genes were purified and characterized. Both proteins contained folate and flavin cofactors, and have a weak DNA photolyase activity. A phylogenetic analysis revealed that the seven candidates actually belong to the new type of cryptochrome subfamily. This is the first report of the CRY-DASH members from vertebrates and fungi. 相似文献
137.
Wakamatsu T Saito T Hayashi J Takeichi T Kitamoto K Aizawa K 《Medical molecular morphology》2005,38(4):225-232
Flexible treatments for intimal hyperplasia after angioplasty are still needed. The aim of this study was to demonstrate the
long-term effects of vascular photodynamic therapy with talaporfin sodium on intimal hyperplasia following interventional
injury. Intimal hyperplasia was induced by balloon distension injury to the carotid artery in 31 rabbits. Talaporfin, 5.0 mg/kg,
was delivered systemically immediately after balloon injury. The injury site was irradiated with a diode laser light of wavelength
664 nm using a fluence of 50 J/cm2 after 30 min. At day 3 and weeks 3, 6, 9, 15, and 25 after photodynamic therapy, the treated artery of each rabbit was excised
and examined immunohistochemically. Thirty minutes after talaporfin administration, drug fluorescence was found only in the
balloon-injured carotid artery wall. At 3 days, no smooth muscle cells were seen in the media of the photodynamic therapy-treated
arterial segments. Intimal hyperplasia developed progressively in the balloon-injured and untreated segments; however, in
the segments treated with photodynamic therapy, intimal hyperplasia was markedly suppressed until 25 weeks and the media was
repopulated by smooth muscle cells without macrophages. Vascular photodynamic therapy with talaporfin may be used to inhibit
restenosis after vascular intervention.
An erratum to this article is available at . 相似文献
138.
Redistribution of fibroblasts and macrophages as micrometastases develop into established liver metastases 总被引:1,自引:0,他引:1
Higashi N Ishii H Fujiwara T Morimoto-Tomita M Irimura T 《Clinical & experimental metastasis》2002,19(7):631-638
Fibroblastic tissue is an important component of malignant tumors, involved in the establishment of metastatic foci from micrometastases,
and thought to prevent invasion of metastatic tumor cells into surrounding tissue. However, experimental models of fibrosis
during the growth of micrometastasis into established metastases were not previously available. In the present paper, we performed
immunohistochemical studies on experimental hepatic metastasis with colon 38 mouse colon carcinoma cells injected into syngeneic
C57BL/6 mice. Early and late stages of metastatic nodules were examined for the distribution of endothelial cells, fibroblasts,
and macrophages by the use of markers of these cells. One week after intrasplenic injection of colon 38 cells, micrometastases
mainly appeared in the region of sinusoids accompanied with invasion of F4/80-positive Kupffer cells. Transitional metastases
can be defined based on the histological appearance and intensive infiltration of both macrophages and fibroblasts. These
transitional metastases were connected by protrusions of fibroblast-rich tissues co-localized with collagen-rich matrix and
CD31-positive cells. This protrusion preceded fibrosis formation characteristics to established metastases associated with
angiogenesis and segregation of tumor cells from host cells. Three stages can thus be classified during the development of
hepatic metastasis in this syngeneic experimental system: micrometastasis, transitional metastasis, and established metastasis.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
139.
Takeshi Komoda MD Thorsten Drews MD Hans B. Lehmkuhl MD Roland Hetzer MD PhD 《Journal of artificial organs》2006,9(1):29-33
The Eurotransplant (ET) allocation algorithm, newly implemented in 2000, gives priority for heart transplantation (HTx) to
patients with high urgency (HU) status, but now this status is rescinded upon ventricular assist device (VAD) implantation
and only regained if severe complications occur during mechanical circulatory support (MCS). We studied the effects of this
change on the patients in our institute who were waiting for HTx with MCS. The median duration of MCS until HTx in adult patients
gradually increased from 3.1 months in 1994, reaching a peak of 16.7 months in 2000, and then gradually decreased to 6.0 months
in 2003. Among the patients with VAD implantation as a bridge to HTx, two patients were on MCS for more than 1 year (the longest
duration of MCS being 1.6 years) at the end of 1999, and this figure increased to nine patients and a maximum MCS duration
of 3.7 years at the end of 2003. These data imply that the patients in whom a complication occurred in the early phase of
MCS and who had overcome this complication underwent HTx early with HU status, and those who were stable during MCS waited
a long time for HTx. Furthermore, the number of patients in the latter group is increasing. The new allocation algorithm imposes
on patients with MCS waiting for HTx who are relatively young and free from complications and serious coexisting disease,
very long-term MCS without an end to VAD bridging, which is almost equivalent to destination therapy.
Part of this paper was presented at the 42nd JSAO Conference (Tokyo, October 5–7, 2004) 相似文献
140.
Sazuku Nisitani Takeshi Tsubata Masao Murakami Tasuku Honjo 《European journal of immunology》1995,25(11):3047-3052
Activation mechanisms of B-1 (Ly-1 B) cells have been suggested to be different from those of conventional B cells. To assess the role of various interleukins (IL) in the activation of B-1 cells, we injected IL-4, IL-5 or IL-10 into nonanemic anti-red blood cells (RBC) autoantibody-transgenic mice, in which conventional B cells are clonally deleted but peritoneal B-1 cells persist without secreting Ig. Intraperitoneal or intramuscular injection of IL-5 or IL-10, but not IL-4, increased the number of antibody-producing peritoneal B-1 cells by four- to five-fold, resulting in increased anti-RBC serum autoantibody and induction of hemolytic anemia. These results suggest that IL-5 or IL-10 may play an important role in the terminal differentiation of B-1 cells into antibody-producing cells in vivo. 相似文献