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51.
A rare case of parosteal fasciitis arising from the periosteum of the left clavicle in a 27-year-old woman is reported. Magnetic resonance imaging demonstrated the lesion surrounding the periosteum of the clavicle. The lesion was iso-intense with muscle on T(1)-weighted images and hyperintense on T(2)-weighted images. At surgery, the lesion was discovered to be densely adherent with the periosteum, and excised along with the periosteum. Histopathological examination revealed the proliferation of myofibroblasts in a vague storiform or short fascicular pattern. A large amount of extravasated erythrocytes, and a few lymphocytes were present in the matrix. There were some foci of abundant myxoid materials. Immunohistochemical study showed the cells to be positive for vimentin, alpha-smooth muscle actin and HHF35, but negative for desmin. There was no local recurrence at a 6 months postoperative follow up.  相似文献   
52.
Carnosine is a naturally occurring dipeptide (β-alanyl-l-histidine) present in mammalian tissues such as the brain and skeletal muscles. Carnosine is not only a radical scavenger but also a possible neurotransmitter-like molecule that regulates neuronal functions such as hypothalamic control of the autonomic nervous system. CN2 (CNDP2) is a cytosolic enzyme that can hydrolyze carnosine to yield l-histidine and β-alanine. In order to understand the functions of carnosine and CN2 in the brain, we have investigated the immunohistochemical localization of CN2 in the hypothalamus. CN2-immunoreactivity was highly concentrated in neuronal cells in the dorsal part of the tuberomammillary nucleus of the posterior hypothalamus. Since the tuberomammillary nucleus is the exclusive origin of histaminergic neurons, we further investigated whether CN2 is present in the histaminergic neurons. We found that CN2-immunoreactivity was colocalized with that of histidine decarboxylase, which is the key enzyme for histamine biosynthesis specifically expressed in the histaminergic neurons of the tuberomammillary nucleus. These results suggest that CN2 is highly expressed in the histaminergic neurons in the tuberomammillary nucleus, implying that it may supply histidine to histaminergic neurons for histamine synthesis.  相似文献   
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Fas antigen is constitutively expressed in the normal colon epithelium, but considerably diminished in most colorectal carcinomas. In the present study, we examine the relationship between Fas antigen expression and apoptosis using the colorectal carcinoma cell line COLO 201, on which a low grade of Fas antigen is expressed. Anti-Fas antibody had no effect on the induction of apoptosis of COLO 201. However, TNF-α and/or IFN-γ, independently and additively, up-regulated Fas antigen expression on COLO 201 and induced apoptosis in a dose-dependent manner. Both cytokines also increased the COLO 201 sensitivity to anti-Fas antibody, resulting from the down-modulation of Bcl-2 and the up-regulation of Bax. These findings indicate that cytokine(s) plus anti-Fas antibody (which mimics natural Fas ligand) are more effective in inducing apoptosis of COLO 201 than cytokine(s) alone. These findings suggest that immunotherapy in combination with cytokine(s) and lymphokine-activated killer (LAK) cells will become a more effective therapy for cancer than cytokine(s) or LAK cells alone, since the Fas ligand is expressed on activated T cells, natural killer cells and macrophages.  相似文献   
56.
Summary The immunofluorescent localization of glomerular basement membrane (GBM) antigens was examined in 52 specimens from normal kidneys and in various renal diseases using antisera to human GBM HGBM), IV type collagen (IV Col) and P3 antigen, a rat nephritogen. Anti-HGBM serum normally stained the GBM and the mesangium in a restrictive pattern, anti-IV Col serum stained the GBM and the mesangium in a wider pattern and anti-P3 serum stained only the GBM. In mesangial proliferative glomerulonephritis, including IgA nephropathy pathy and Henoch-Schönlein nephritis, the widened mesangial areas were stained with anti-HGBM and anti-IV Col sera. In membranous nephropathy, the punched-out lesions of thickened GBM were demonstrated with the three antisera in moderate cases and a double linear distribution with fine granulation with anti-HGBM and anti-IV Col sera were revealed in one severe case. In membranoproliferative glomerulonephritis, the expanded mesangium and thickened capillary walls were stained with anti-HGBM and anti-IV Col sera, while the outer line of glomerular capillary walls was only positive with anti-P3 serum. In crescentic glomerulonephritis, the collapsed glomerular tufts were stained normally with anti-HGBM and anti-P3 sera and weakly with anti-IV Col serum. In diabetic nephropathy, anti-HGBM serum stained the GBM in a double linear distribution without reacting with the expanded mesangium; anti-IV Col serum stained the mesangium and the GBM in a less clear double linear fashion while anti-P3 serum stained the GBM as single line. Thin membrane disease and Alport's syndrome had normal reactivity with all antisera. However, in one case of Alport's syndrome anti-HGBM and anti-P3 sera stained the GBM in a focal and segmental pattern, while normal staining with anti-IV Col serum was found. In lesions with adhesions and crescents the staining was positive for HGBM and IV Col and negative for P3; obsolescent glomeruli were stained with anti-HGBM and anti-P3 sera, and had diminished staining with anti-IV Col serum.The identification of the various structural glomerular antigens is useful in the classification of certain types of glomerular diseases. Further insight into the mechanisms underlying these conditions may be obtained in this way.  相似文献   
57.
An electron microscopic immunohistochemical localization of thyroglobulin (TG) using PAP methods has been made in 15 cases of cold follicular adenoma. All cases of follicular adenoma showed organ specific functions such as synthesis, storage, reabsorption, and hydrolysis of thyroglobulin except for an area composed of follicular cells with trabecular arrangement. Immuno-reaction product for TG was precisely demonstrated in follicular lumina, subapical vesicles and reabsorbed colloid droplets. The reaction product observed in the follicular lumen was clearly demarcated from the cytoplasm of the follicular cells by the apical plasma membrane. The subapical vesicles ranging approximately from 50 mμ to 300 mμ in diameter were rarely observed in follicular adenoma and some of them fused with the reabsorbed colloid droplets. The reabsorbed colloid droplets usually had the intense reaction product and hydrolyzed colloid droplets had a vacuole containing floccular low electron dense materials. There is no reaction product in rough endoplasmic reticulum and Golgi complexes.  相似文献   
58.
Epithelioid leiomyosarcoma in the external deep soft tissue is extremely rare. Most epithelioid leiomyosarcomas occur in the uterus. We present a case of epithelioid leiomyosarcoma occurring in the muscle of the thigh of a 78-year-old man. Histologically, the tumor predominantly consisted of round or polygonal cells arranged in sheets with a focal spindle cell component. Immunohistochemical analysis revealed that the tumor cells expressed vimentin, alpha-smooth muscle actin, and alpha-sarcomeric actin. The tumor was negative for desmin, S100 protein, glial fibrillary acidic protein, pan-keratin, epithelial membrane antigen, CAM 5.2, HMB-45, leukocyte common antigen, factor VIII-associated antigen, and CD34. Electron microscopically, some tumor cells contained abundant actin-type filaments in their cytoplasm.  相似文献   
59.
We have recently established a new bone marrow transplantation (BMT) method for the treatment of intractable autoimmune diseases in MRL/lpr mice; the method consists of fractionated irradiation (5.5 Gy x 2), followed by BMT of whole bone marrow cells (BMCs) from allogeneic C57BL/6 mice via the portal vein (abbreviated as 5.5 Gy x 2 + PV). In the present study, we investigate the mechanisms underlying the early engraftment of donor-derived cells in MRL/lpr mice by this method. In the mice treated with this method, the number of donor-derived cells possessing the mature lineage (Lin) markers rapidly increased in the BM, spleen, and liver; almost 100% were donor-derived cells by 14 days after the treatment. The number of donor-derived hemopoietic progenitor cells (defined as c-kit(+)/Lin(-) cells) increased in the BMCs, hepatic mononuclear cells, and especially spleen cells by 14 days after the treatment. Simultaneously, hemopoietic foci adjoining donor-derived stromal cells were observed in the liver when injected via the PV, but not via the peripheral vein (i.v.). When adherent cell-depleted BMCs were injected via the PV, recipients showed a marked reduction in the survival rate. However, when mice were transplanted with adherent cell-depleted BMCs with cultured stromal cells, all the recipients survived. These findings suggest that not only donor hematopoietic stem cells (HSCs) but also donor stromal cells administered via the PV were trapped in the liver, resulting in the early engraftment of donor HSCs in cooperation with donor-derived stromal cells. This new strategy to facilitate the early recovery of hemopoiesis would therefore be of great advantage in human application.  相似文献   
60.
In this report, we provide evidence using a serial bone marrow transplantation (BMT) protocol that intra-bone marrow (IBM)-BMT (IBM-BMT) can efficiently reconstitute the hemopoietic system with cells of donor origin, in contrast to conventional intravenous (IV)-BMT (IV-BMT). Furthermore, the hematolymphoid system of secondary recipients that had received bone marrow cells (BMCs) from primary recipients treated with IBM-BMT recovered earlier than that of the secondary recipients of BMCs from primary recipients treated with IV-BMT. This was the case when the Lin-/c-kit+ progenitor cells of the secondary and tertiary recipients were examined. These findings indicate that IBM-BMT can facilitate the development of not only cells of various lineages but also the effective generation and, more importantly, the maintenance of the progenitor cells. Furthermore, we show that IBM-BMT can reconstitute the dendritic cell (DC) subsets (myeloid and lymphoid DCs), which are critical for the initiation of both adaptive and innate immune responses. The frequency of both myeloid and lymphoid DC subsets was approximately equal to that of normal age-matched untreated controls and, after second and third BMT, this ratio was close to that observed in the normal controls. However, the lymphoid DCs were clearly reduced in the secondary and tertiary recipients of BMCs from mice that had received IV-BMT. Therefore, the development of DC subsets is also normally maintained in the IBM-BMT group.  相似文献   
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