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BACKGROUND: Bilateral nasal polyposis (NP) is characterized by high concentrations of IgE in NP tissue, which show no relation to the atopic status. We aimed to study the relationship between systemic and local IgE formation, nasal carriage of Staphylococcus aureus and nasal polyposis. METHODS: In serum and nasal tissue homogenates from 24 NP patients and 12 controls, we determined concentrations of total IgE and IgE antibodies to inhalant allergens and S. aureus enterotoxins (SAEs; A,B,C,D,E,TSST) by ImmunoCAP. Tissue cryosections were stained for CD3, CD20, CD38, CD23, FcepsilonRI, IgE and SEA/SEB. RESULTS: We demonstrated a higher incidence of S. aureus colonization (17/24) and IgE antibodies to SAEs in NP tissue (12/24) compared with controls (3/12 and 0/12, respectively). Total IgE and IgE antibodies in serum and NP tissue were dissociated because of local polyclonal IgE formation in NP tissue. Staining of NP tissue revealed follicular structures characterized by B and T cells, and lymphoid accumulations with diffuse plasma cell infiltration. CONCLUSIONS: We demonstrated the organization of secondary lymphoid tissue in polyp tissue and a polyclonal hyper-immunoglobulinemia E associated with the presence of IgE antibodies to SAEs, colonization with S. aureus, and tissue eosinophilia in a relevant subgroup of polyp patients.  相似文献   
74.
数值模拟鼻甲的切除对鼻腔内气体流场的影响   总被引:3,自引:0,他引:3  
量化研究鼻腔结构的变化对鼻腔内气体流场分布的影响.通过CT图像对鼻腔结构进行三维重建并用有限元方法对气体流场进行数值分析.对重建的鼻腔模型的一侧,分别去掉部分中鼻甲和部分下鼻甲并用有限元方法再次进行数值分析,将得到的结果与原始模型进行比较.观察气体流场分布的变化,在两侧鼻腔的流量分布均有变化,在去掉部分鼻甲的一侧流场和气压的分布也有所改变.通过数值模拟,我们量化的显示了鼻腔结构的变化对鼻腔内气体流场分布的影响.  相似文献   
75.
Articular cartilage has a limited capacity for self-repair. To overcome this problem, it is expected that functional cartilage replacements can be created from expanded chondrocytes seeded in biodegradable scaffolds. Expansion of chondrocytes in two-dimensional culture systems often results in dedifferentiation. This investigation focuses on the post-expansion phenotype of human nasal chondrocytes expanded on macroporous gelatin CultiSpher G microcarriers. Redifferentiation was evaluated in vitro via pellet cultures in three different culture media. Furthermore, the chondrogenic potential of expanded cells seeded in polyethylene glycol terephthalate/ polybuthylene terephthalate (PEGT/PBT) scaffolds, cultured for 14 days in vitro, and subsequently implanted subcutaneously in nude mice, was assessed.

Chondrocytes remained viable during microcarrier culture and yielded doubling times (1.07±0.14 days) comparable to T-flask expansion (1.20±0.36 days). Safranin-O staining from pellet culture in different media demonstrated that production of GAG per cell was enhanced by microcarrier expansion. Chondrocyte–polymer constructs with cells expanded on microcarriers contained significantly more proteoglycans after subcutaneous implantation (288.5±29.2 μg) than those with T-flask-expanded cells (164.0±28.7 μg). Total collagen content was similar between the two groups.

This study suggests that macroporous gelatin microcarriers are effective matrices for nasal chondrocyte expansion, while maintaining the ability of chondrocyte differentiation. Although the exact mechanism by which chondrocyte redifferentiation is induced through microcarrier expansion has not yet been elucidated, this technique shows promise for cartilage tissue engineering approaches.  相似文献   

76.
AIMS: To elucidate the pathogenesis of the anal fibroepithelial polyp, we examined surgically resected lesions histopathologically. METHODS AND RESULTS: Twenty-seven surgically resected anal fibroepithelial polyps were investigated histologically with an additional immunohistochemical examination using anti-CD34. For a control study, the surgical specimens of the anal canal showing non-polypoid lesions, obtained from haemorrhoidectomy (18 specimens) and rectectomy (five specimens) due to rectal cancer without anal canal involvement, were also analysed. We demonstrated characteristic spindle or stellate cells immunohistochemically positive for CD34 in the anal fibroepithelial polyps (24/27, 89%). The number of CD34+ cells was statistically related to the size of anal fibroepithelial polyps, although CD34+ stromal cells were recognized in the non-polypoid anal submucosa and haemorrhoids. We also found hyalinized vascular changes in the base of six anal fibroepithelial polyps examined. These features were not detected in the non-polypoid anal canal. CONCLUSIONS: An increase in CD34+ stromal cells may play a role in the enlargement of anal fibroepithelial polyps. CD34+ stromal cells are suggested to be distinctive mesenchymal cells with a capability for tissue repair and overgrowth. The vascular impairment could be secondary change associated with localized tissue damage by abnormal traction.  相似文献   
77.
The results of several retrospective studies allow us to conclude that the detection of fundic gland polyps (Elster's cysts) is associated with an increased incidence of colorectal tumors. In this survey, we present the results of a prospective study investigating such a possible relationship. A total of 144 patients were investigated, of whom 80 had fundic gland polyps of the gastric corpus mucosa. Sixty-four of these patients underwent a colonoscopy, whereas the other 64 patients belonged to a sex- and age-matched control group with no fundic gland polyps. In the group with known fundic gland polyps, colorectal neoplasias were found in 29 (45.3%) patients. Eight of these patients had (12.5%) adenocarcinomas, 3 (4.7%) had high-grade intraepithelial neoplasia, and 18 (28.1%) had tubular adenomas. In one patient, a synchronous carcinoma of the rectum and the colon was detected. In comparison, 6 patients of the control group (9.3%) developed tubular adenomas and 9 (14.1%) had hyperplastic polyps of the colonic and rectal mucosa. Our results suggest that it is necessary to conduct a careful diagnostic work-up of the colon in patients with gastric fundic gland polyps.  相似文献   
78.
BACKGROUND: Studies have suggested that topical corticosteroids are effective in the treatment of nasal polyps; however, this has yet to be confirmed in a large, robust clinical trial. OBJECTIVE: To evaluate the efficacy and safety of mometasone furoate nasal spray (MFNS) for nasal polyposis. METHODS: A total of 354 subjects with bilateral nasal polyps and clinically significant congestion/obstruction participated in this multinational, randomized, double-blind, placebo-controlled study. Subjects received MFNS 200 microg once or twice daily or placebo for 4 months. Coprimary endpoints were (1) change from baseline to last assessment in physician-evaluated bilateral polyp grade score and (2) change from baseline averaged over month 1 in subject-assessed nasal congestion/obstruction. ANOVA was used for all efficacy endpoints, except for change in bilateral polyp grade score, for which baseline polyp grade was added as a covariate. RESULTS: Compared with placebo, MFNS 200 microg administered once or twice daily produced significantly greater reductions in bilateral polyp grade score (P < .001, P = .010, respectively) and congestion/obstruction (P = .001, P < .001), as well as improvement in loss of smell (P < .001, P = .036), anterior rhinorrhea (P < .001 for both), and postnasal drip (P < .001, P = .001) over month 1. MFNS 200 microg twice daily was superior to MFNS 200 microg once daily in reducing congestion/obstruction (P = .039), and there were more improvers in the MFNS 200 microg twice daily group (P = .035). MFNS was well tolerated in both groups. CONCLUSION: MFNS 200 mug, once or twice daily, was safe and significantly superior to placebo in reducing polyp grade (size and extent) and improving congestion/obstruction and return of sense of smell. MFNS is an effective medical treatment for nasal polyposis and may reduce or delay the need for surgery.  相似文献   
79.
Responses of nasal mucociliary transport mechanisms to exposure to 6 ppm SO2 were studied in chickens in vivo. This model takes advantage of the natural cleft palate which exposes the mucociliated base of the nasal septum. Exposure to 6 ppm SO2 decreased the mucociliary transport rate along the base of the nasal septum. The minimum force required to move an iron particle along this area of mucous membrane by use of a magnetic field in vivo increased significantly after SO2 exposure, while the minimum force required to move an iron particle on a pool of mucus collected from the same chicken and tested in vitro showed no change after SO2 exposure. The elastic recoil distance of mucus was measured both in vivo and in vitro. The in vivo recoil distance decreased significantly after SO2 exposure, while SO2 exposure did not change recoil distance in vitro. It is proposed that exposure of chickens to SO2 results in the formation of multiple points of adhesion of strands of mucus between the acinar gland cells and the emergent extracellular mucus or adhesion of a mucous blanket to the cilia, causing mucociliary transport to be retarded or static.  相似文献   
80.
过敏性哮喘患者鼻分泌液中分泌性IgA含量的测定   总被引:1,自引:1,他引:1  
本文对26例过敏恶性性支气管哮喘患者鼻分泌液中SIgA含量等进行了超速离心检测,结果表明:患者鼻分泌液中SIgA,IgA,总IgA含量均较正常人明显增加(P<0.05,<0.01,<0.05)。IgA对白蛋白的相对分泌系数与正常人无明显差异(P<0.05)。结合其它研究认为过敏性哮喘患者呈粘膜SIgA免疫高反应状态。  相似文献   
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