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11.
12.
ATP is the major excitatory transmitter from chemoreceptor type I cells to sensory nerve endings in the carotid body, and has been suggested to be released by exocytosis from these cells. We investigated the mRNA expression and immunohistochemical localization of vesicular nucleotide transporter (VNUT) in the rat carotid body. RT-PCR detected mRNA expression of VNUT in extracts of the tissue. Immunoreactivity for VNUT was localized in a part of type I cells immunoreactive for synaptophysin (SYN), but not in glial-like type II cells immunoreactive for S100 and S100B. Among SYN-immunoreactive type I cells, VNUT immunoreactivity was selectively localized in the sub-population of tyrosine hydroxylase (TH)-immunorective type I cells associated with nerve endings immunoreactive for the P2X3 purinoceptor; however, it was not detected in the sub-population of type I cells immunoreactive for dopamine beta-hydroxylase. Multi-immunolabeling for VNUT, P2X3, and Bassoon revealed that Bassoon-immunoreactive products were localized in type I cells with VNUT immunoreactivity, and accumulated on the contact side of P2X3-immunoreactive nerve endings. These results revealed the selective localization of VNUT in the subpopulation of TH-immunoreactive type I cells attached to sensory nerve endings and suggested that these cells release ATP by exocytosis for chemosensory transmission in the carotid body.  相似文献   
13.
Solitary fibrous tumors are mesenchymal entities integrated in a mixed group of hemangiopericytoma-like neoplasms. Although classically presented as a pleura-based mass, there are extrapleural sites including the lung. We present the clinical, imaging, and histological features of a solitary fibrous tumor of the lung.  相似文献   
14.
Ficolins, a group of oligomeric lectins consisting of three isoforms (H‐, L‐ and M‐ficolin), contribute to innate immunity via activating the complement pathway and/or acting directly as opsonins against pathogens and apoptotic cells. Because apoptotic cells likely drive the development of systemic sclerosis (SSc) partly through innate immunity, we assessed the clinical association of serum H‐ficolin levels in SSc patients. Despite no difference in serum H‐ficolin levels between SSc and control subjects, SSc patients with decreased serum H‐ficolin levels tended to have a higher prevalence of interstitial lung disease (ILD). More importantly, serum H‐ficolin levels inversely correlated with ground‐glass opacity score on chest computed tomography in SSc‐ILD patients. Therefore, H‐ficolin‐related innate immunity may be involved in SSc‐ILD development.  相似文献   
15.
Heparin‐binding epidermal growth factor (EGF)‐like growth factor (HB‐EGF) is a member of the EGF family growth factors, which affects multiple aspects of the wound healing process such as epithelialization, wound contraction and angiogenesis. In our study, we measured the serum HB‐EGF levels of 51 systemic sclerosis (SSc) patients, which showed a significant increase compared with those of 20 normal subjects. Further analysis revealed a positive correlation between the HB‐EGF level and pulmonary ground‐glass score but no correlation between the former and pulmonary fibrosis score. Other findings include: a significant increase of serum sialylated carbohydrate antigen KL‐6 levels and significant shortness of disease duration in the diffuse cutaneous SSc patients with elevated HB‐EGF levels; and significantly higher HB‐EGF levels in the presence of Raynaud's phenomenon, in that of telangiectasia, and in the absence of contracture of phalanges in all SSc patients. We then evaluated HB‐EGF mRNA levels of fibroblasts harvested from skin samples of the SSc patients and those of foreskin‐derived fibroblasts treated with transforming growth factor‐β, both of which were significantly higher than each control. In conclusion, we speculate that HB‐EGF plays a pro‐inflammatory role in the active skin and lung lesions of SSc.  相似文献   
16.
Graft tunnel placement is the factor with most influence on the outcome of double-bundle anterior cruciate ligament (ACL) reconstruction. However the final decision for the graft location has to be decided subjectively under arthroscopy, and can be misplaced due to the effect of the knee flexion angle. The displacement of the estimated placement by surgeons from the ACL anatomical attachment is due to the knee’s differing knee flexion angle. Eight cadaveric knees and an electromagnetic position recording system were employed. After digitizing the anatomical location of AM and PL bundle center, four experienced surgeons estimated the graft placement repeatedly at 70°, 90° and 110° of knee flexion. The displacements between these two positions were calculated and analyzed separately in antero-posterior and disto-proximal directions. The displacements of the estimated AM bundle placements were 4.7 ± 3.4 mm at 70°, 4.3 ± 2.2 mm at 90°, and 6.0 ± 2.6 mm at 110°, while those of the PL bundle were 4.0 ± 2.2 mm at 70°, 3.4 ± 1.9 mm at 90°, and 4.2 ± 2.5 mm at 110°. The best results were obtained at 90° of knee flexion. Additionally, the estimated placements for both AM and PL bundle were located more distally as the flexion angle increased. Our results imply that the knee should be set at 90° when determining the graft placement in double-bundle reconstruction to prevent misplacement of the graft usually in a disto-proximal direction.  相似文献   
17.
Our previous study showed that the saliency of a target increases the gain of smooth pursuit initiation. In this study, we examined the interocular transfer of this effect in five humans. A square red frame surrounding the target was used as a cue to indicate the initial target position. In the cue condition, the responses were similar, irrespective of the eye to which the cue was presented, and were significantly larger than in the no-cue condition. The result suggests that central pathways that receive input from both eyes mediate the effect of saliency on smooth pursuit initiation.  相似文献   
18.
Carcinosarcoma of the esophagus is a rare tumor with a distinct pathological entity having squamous cell carcinoma as the most described carcinomatous component. This paper reports the first case of carcinosarcoma of the esophagus that showed predominant basaloid squamous carcinoma component in addition to squamous cell carcinoma and poorly differentiated carcinoma and sarcoma component. A 64-year-old male patient consulted for dysphasia and chest pain was examined and found to have gastrointestinal fiber-endoscope and a polypoid growth in the lower third of the esophagus. Partial esophagectomy was performed and the excised tumor showed histological features of carcinosarcoma with heterogeneous carcinomatous components with dominance of basaloid squamous carcinoma and minority of squamous cell carcinoma, poorly differentiated carcinoma, and sarcomatous component, immunohistochemically proven to be rhabdomyosarcoma. Immunohistochemical study and TP53 mutation analysis was carried out to explain the histogenesis of this rare tumor. The distinct immunohistochemical profiles of the carcinomatous and sarcomatous components suggested the possibility of transition from a carcinomatous to a sarcomatous component. The similar TP53 mutation in the carcinomatous and sarcomatous component suggested each of these components had the same origin, that is, the tumor was monoclonal in origin.  相似文献   
19.
Interferon regulatory factor-1 (IRF-1) is pivotal in the regulation of interferon (IFN)-mediated immune reactions, and studies suggest that IRF-1 is involved in the development of autoimmune diseases. IRF-1+/+, +/-, and -/- nonobese diabetic (NOD) mice were immunized with mouse thyroglobulin (mTg) to determine whether IRF-1 is required in experimental autoimmune thyroiditis (EAT), a murine model for Hashimoto's thyroiditis (HT). IRF-1-deficient mice developed EAT and anti-mTg antibodies comparable to IRF-1+/+ and +/- mice. Whereas both CD4+ and CD8+ T cells were found in thyroids of IRF-1+/+ mice, the latter was not in IRF-1-/- mice. Major histocompatibility complex class II antigen was comparably expressed in thyroids of IRF-1+/+ and -/- mice. Lack of IRF-1 resulted in decreased CD8+ T cell number in the spleen and reduced IFNgamma production by splenocytes. Our results suggest that IRF-1 is not pivotal in EAT in NOD mice.  相似文献   
20.
The integrin VLA-2 as a collagen receptor and VLA-5 as a fibronectin receptor were detected immunohistochemically in normal, benign tumor and carcinoma tissues of the breast. Both proteins were also detected by Western-blot analysis in some carcinoma cases. Epithelial and myoepitheiial cells of both normal breast and benign tumor were in all cases immunoreactive for VLA-2 in the plasma membrane. Carcinoma cells in the invasive component were not immunoreactive for VLA-2 in 31 (46%) of 67 cases. Carcinoma cells in the intraductal components were negative for VLA-2 in only 4 (11%) of 36 cases, while 20 cases (56%) showed weak expression and 12 cases (33%) showed strong expression. Metastatic carcinoma cells in the lymph nodes of 6 cases showed no immunoreactivity except in one case, whereas, again with the exception of one case, the carcinoma cells in the primary tumors did show VLA-2 expression. With regard to VLA-5, there was no difference in its expression in the invasive components and the intraductal components. These findings suggest that the loss of VLA-2 plays a role in the invasion and metastasis of breast carcinoma.  相似文献   
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