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Type II collagen (CII) is of immunological interest because of its repetitive structure and properties as an autoantigen. The mouse gene has recently been cloned, thus enabling T cell-defined epitopes to be identified. Multiple novel epitopes on mouse CII are here detected in the autoreactive T cell response. The major response is directed to an epitope with residues 707-721 located on the CB10 fragment. Some 25 other epitopes are also recognized, including the autologous homologue of the 256-270 epitope which dominates in the response to foreign collagen. The cells reactive with mouse collagen peptides were of Th1 type, as judged by release of IFN-gamma. No significant reactivity was detected to mouse CII peptides during ongoing disease. Alignment of the mouse epitopes revealed a sequence motif with characteristic side chains at residues P1, P4 and P7, and to a lesser extent at P5, within a nonamer core sequence. Binding of these epitopes was simulated in a computer model of the I-Aq molecule, where peptides with anchor residues at P1, P4 and P7 were indeed found to fit the binding groove best. The spacing of pockets and the fine structure of the binding surface of the I-Aq molecule meshes with the repetitive structure of the collagen (X-Y-Gly), thus providing a likely explanation for the occurrence of multiple epitopes. Comparison with human DR binding motifs showed that the I-Aq motif resembles most closely that of the DR4 subtypes which predispose for rheumatoid arthritis.   相似文献   
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BACKGROUND: Nitric oxide (NO) has contradictory roles in the pathophysiology of allergic inflammation in both allergic rhinitis (AR) and asthma. Small amounts of NO produced by constitutive NO synthase (NOS) is anti-inflammatory, whereas large amounts produced by inducible NOS (iNOS) are proinflammatory. OBJECTIVE: To investigate the difference in constitutive endothelial NOS (eNOS) and iNOS expression in nonallergic and allergic mucosa and the possible relation of this to the coexistence of asthma in seasonal AR. METHODS: Seventeen patients (10 women and 7 men) with seasonal AR and 9 nonallergic patients (5 women and 4 men) with nasal septum deviation were enrolled. Inferior turbinate nasal biopsy specimens were obtained in all. Levels of eNOS and iNOS expressed as immunohistochemical scores (HSCOREs) were determined immunohistochemically from the specimens. RESULTS: The mean +/- SD HSCOREs for eNOS in patients with seasonal AR were not significantly different from those of the nonallergic controls (1.85 +/- 0.78 vs 1.63 +/- 0.54; P = .12). On the other hand, the mean +/- SD HSCOREs for iNOS were significantly higher in patients with seasonal AR (1.75 +/- 0.75 vs 0.71 +/- 0.6; P = .004). Furthermore, although eNOS expression was not different between seasonal AR patients with and without asthma, the mean +/- SD HSCOREs for iNOS were significantly higher in the patients with asthma (1.93 +/- 0.78 vs 1.65 +/- 0.55; P = .01). CONCLUSION: Increased expression of iNOS might have a role in the development of allergic inflammation in upper and lower airways and in comorbidity of AR and asthma.  相似文献   
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The effect of orthodontic‐surgical treatment on submental‐cervical region was evaluated in a very limited number of studies. The aim of this study was to evaluate submental‐cervical soft tissue contour changes following mandibular advancement and set‐back procedures via bilateral sagittal split ramus osteotomy. Sixty‐seven patients were included in this study. Group 1 consisted of 27 skeletal Class II patients who underwent mandibular advancement surgery, whereas Group 2 consisted of 40 skeletal Class III patients who underwent mandibular set‐back surgery. Various linear and angular measurements were performed on pre‐operative and sixth month post‐operative cephalometric radiographs. A new method was used to evaluate the amount of sagging at submental region. The submental length did not change in Group 1; however, it decreased significantly in Group 2 (P < 0·05). The angle between submental plane and facial plane decreased to 95·9° from 98·8° in Group 1(P < 0·05), whereas it increased to 93·1° from 88·2° in Group2 (P < 0·05). The change of submental soft tissue sag was almost stable in Group 1, while 0·34 mm increase of sag was observed in Group 2. This increase was not statistically significant (P > 0·05). Mandibular set‐back and advancement procedures do not remarkably change the submental sag following approximately 6 mm jaw movement. Although mandibular advancement did not significantly effect submental length, soft tissue followed mandibular set‐back with a ratio of 1:1 at C‐point to projection of soft tissue pogonion and 1:0·7 at C‐point to soft tissue menton distances.  相似文献   
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The aim was to compare pneumatic and holmium:yttrium-aluminum-garnet laser in the treatment of impacted ureteral stones with different locations and to identify the risk factors for complications. Between March 2005 and November 2012, a total of 230 patients underwent ureteroscopic lithotripsy for impacted stones. Of the patients, 117 had pneumatic and 113 had laser lithotripsy for the fragmentation of the stones. Treatment outcomes based on evidence of being stone free were evaluated. Preoperative, operative, and postoperative follow-up findings were analyzed and compared. There was a difference between the two groups according to overall stone clearance rate (93.8% vs. 80.3%, p = 0.002). There was no statistically significant difference for distal location between the laser and pneumatic groups (96.8% vs. 91.7%, p = 0.288). For 10 patients with intrarenally migrated stones who were managed with flexible ureterorenoscopy in the same session, laser lithotripsy was more successful than pneumatic for proximal ureteral stone (94.4% vs. 67.9%, p = 0.007). The overall complication rate was 26.1%. There was no statistically significant difference between the two groups (29% vs. 23%, p = 0.296). Multivariate logistic regression analysis revealed that the proximal location was a statistically significant parameter for the occurrence of complications in both groups (p = 0.001 for PL, p = 0.004 for laser). The pneumatic and holmium:yttrium-aluminum-garnet laser lithotripsy are effective in the treatment of distal impacted stones. Both treatments with semirigid ureteroscopy are acceptable for proximal impacted ureteral stones, but holmium laser lithotripsy has an advantage of use with flexible ureteroscope for intrarenally migrated stone.  相似文献   
6.
The presence of the Onodi cell (OC) may be accompanied by morphological variations of the neighboring anatomic structures. Such variations carry significant surgical implications and challenges. Pneumatization of the sphenoid sinus induces anterior clinoid pneumatization (ACP), affects the type of the Vidian nerve (VN) canal or alters the courses of the internal carotid artery (ICA), and the optic nerves (ONs) are strongly depending on it. Onodi cell pneumatization may reach and surround the optic nerve in various extension. Our aim in the study was to investigate the effect of Onodi cell’s potential co-existence on these structures. This study was planned as a retrospective and cross-sectional study. This study performed in a tertiary referral center. Coronal computerized tomography images of 999 patients were examined. Using an 64 slices tomography machine, images taken at 3-mm sections were reconstructed using a bone algorithm and evaluated. OCs were present at 212 of the total 320 sides in 160 patients. Type-2 was found to be the most prevalent type of VN canal configuration (Type-2: VN canal partially protrudes into the sphenoid sinus or into the floor of the sphenoid) among all patients (66.5 %) and among those with OCs (71.2 %). The presence or absence of the OC did not cause a statistically significant alteration of the intrasphenoidal course of the VN. The presence of OCs was found to be significant (p < 0.01) in accompanying pneumatization of the anterior clinoid process (34.4 %, 73/212), protrusion (80.1 %, 170/212) and dehiscence (36.3 %, 77/212) of the optic nerve, and protrusion (59 %, 125/212) and dehiscence (20.8 %, 44/212) of the ICA. In 108/320 sides where OCs were absent, no significant correlations existed. This study shows that in the co-existence of an OC, ACP, protrusion and dehiscence of the optic nerve and ICA are encountered at significantly higher rates, while the course of the VN is not necessarily altered.  相似文献   
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