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51.
BACKGROUND: The process of gastro-duodenal digestion may play a role in determining the allergenic properties of food proteins. The sensitizing and allergenic potential of digestion products of highly degraded allergens, such as the major peanut allergen Ara h 1, is currently under debate. We evaluated the effect of in vitro gastro-duodenal digestion of Ara h 1 on T cell reactivity and basophil histamine release. METHODS: An in vitro model of gastro-duodenal digestion was used to investigate changes in the allergenic properties of Ara h 1 using in vitro assays monitoring T cell reactivity (proliferation, cytokine production) and histamine release of basophils from peanut allergic individuals. The digestion process was monitored using an SDS-PAGE gel. RESULTS: In vitro gastric digestion led to rapid degradation of Ara h 1 into small fragments M(r) L5600. Gastric digestion did not affect the ability of Ara h 1 to stimulate cellular proliferation. Gastro-duodenal digestion significantly reduced its ability to stimulate clonal expansion (P<0,05; Wilxocon's signed rank test). The Th-2 type cytokine polarization of T cells from peanut allergic donors (IFN-gamma/IL-13 ratio and IFN-gamma/IL-4 ratio of CFSE(low) CD4(+) T cells) remained unchanged regardless of the level of digestion. Histamine release of basophils from peanut allergic individuals was induced to the same extent by native Ara h 1 and its digestion products. CONCLUSION: Gastro-duodenal digestion fragments of Ara h 1 retain T cell stimulatory and IgE-binding and cross-linking properties of the intact protein.  相似文献   
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53.
Summary The histogenesis of stromal cells in capillary hemangioblastoma has been the subject of debate. The light and electron microscopic studies of hemangioblastomas presented here showed pericytic and leiomyoblastic features in stromal cells. Cells cultured by the monolayer method showed similar features to those of the original tumors. Immunohistochemical studies for glial fibrillary acidic protein and factor VIII/von Willebrand factor indicated that stromal cells were antigenically distinct from astrocytes and endothelial cells. These findings suggest that stromal cells are closely related to pericytes and smooth muscle cells, and support Rhodin's speculation that pericytes serve as a precursor to smooth muscle cells.  相似文献   
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BACKGROUND: Basal cell carcinoma (BCC) is a non-melanoma form of skin cancer that is frequently localized within the cervicofacial area. So far, little research is available on how patients perceive their facial aesthetics after surgical treatment for BCC. OBJECTIVES: To analyse (i) if there was a statistically significant improvement over time with regard to the perceived facial aesthetics of surgical patients; (ii) if there was a significant difference between primary and recurrent BCC patients; and (iii) between patients who had Mohs micrographic surgery (MMS) or surgical excision (SE). To assess (iv) which baseline perceptions and/or clinical parameters may predict the evaluation of facial aesthetics at 6 months after surgery. METHODS: Parallel to a clinical trial, a survey was carried out in which patients were asked, by means of a newly developed disease-specific questionnaire, about perceptions with regard to their facial aesthetics before and after surgery. RESULTS: Aesthetic perceptions of all surgical patients improved over time. There was no statistically significant difference on facial aesthetics between the group with a primary or recurrent BCC and patients treated with MMS or SE. Results also showed that the evaluation of postsurgical facial aesthetics can be predicted by both visibility of the tumour and preoperative perceptions. CONCLUSION: It is recommended to administer preoperatively a short questionnaire in which perceptions related to facial aesthetics are included. In doing so, physicians will become more familiar with the aesthetic problems patients might have regarding their afflicted facial site. Ultimately, it may help physicians in deciding whether patients will benefit from additional cosmetic procedures after surgery.  相似文献   
56.
The current report focuses on two patients of the same age who presented similar appearances on initial anteroposterior chest images. Follow-up images showed superoanterior and superoposterior mediastinal lesions. The first patient with noninvasive cystic thymoma was suspected before surgery, while the pathologic diagnosis was intrathoracic phrenic nerve schwannoma. The second patient was with an asymmetric, dumbbell-shaped paravertebral tumor over T3 and T4 on the left side. The preoperative…  相似文献   
57.
Calcifying odontogenic cyst (COC) has shown to be of extensive diversity in its clinical and histopathological features, as well as in its biological behavior. In this report, a rare case is described of ameloblastoma ex COC (dentinogenic ghost cell tumor) and the relevant literature is briefly reviewed.  相似文献   
58.
Statin, a HMG-CoA reductase inhibitor, was shown to increase BMP-2 gene expression for bone formation, by blocking the mevalonate pathway in cholesterol production. We investigated the effect of naringin, a flavonoid available commonly in citrus fruits, which was also a HMG-CoA reductase inhibitor, in UMR 106 osteoblastic cell line in vitro. The control group consisted of cells cultured without any intervention for different time intervals (24 h, 48 h, and 72 h), whereas the experimental (naringin) group consisted of cells cultured with naringin of different concentrations (0.001 micromol/L, 0.01 micromol/L, and 0.1 micromol/L) for the same time intervals of the control. Colorimetric Tetrazolium (MTT) assay, total protein content assay, and alkaline phosphatase activity were used to measure the cellular activities. Results for the naringin group showed an increase in MTT assay compared with the control and the effect was dose dependent. At high concentration (0.1 micromol), the increases ranged from 60% to 80%. In the total protein content assay, naringin also showed an increase compared with control and the effect was also dose dependent. At high concentration (0.1 micromol), the increases ranged from 9% to 20%. In the alkaline phosphatase activity assay, naringin at high concentration (0.1 micromol) significantly increased the activity up to 20%. In conclusion, naringin significantly increased bone cell activities in vitro. This is the first study specifically attempted to investigate the effect of naringin on bone cell activities. Besides statin, this provided another example of mevalonate pathway blockage in the cholesterol production pathway by HMG-CoA reductase inhibition will increase the bone cell activities.  相似文献   
59.
Neuromuscular biopsy is still an essential method for diagnosing vasculitic neuropathy, although its diagnostic sensitivity is at most 60%. Our objective was to examine the expression of hypoxia‐inducible factor 1α (HIF‐1α) in peripheral nerves and to evaluate its usefulness in diagnosing vasculitic neuropathy, especially for discrimination from other axonal neuropathies. Forty‐one patients with vasculitic neuropathy consisting of 20 definite, 14 probable and seven possible diagnoses, 15 patients with metabolic neuropathy, five with motor neuron disease and six with chronic inflammatory demyelinating polyneuropathy were included. Nerve biopsy specimens were immunohistochemically examined for HIF‐1α and various cell markers. Distinct immunoreactivity (IR) was observed in nuclei of endoneurial cells in 54% (22/41) of vasculitic patients, while specimens from metabolic neuropathies showed less nuclear IR and the difference of mean density of HIF‐1α‐positive nuclei was significant. Two patients with possible vasculitis who showed HIF‐1α‐positive nuclei in endoneurium, were later confirmed to have vasculitis by skin biopsies. Most of the cells expressing HIF were demonstrated to be Schwann cells. There was a trend in the vasculitic patients with early phase nerve damage to display higher endoneurial HIF‐1α‐IR. HIF‐1α may be an immunohistochemical marker for vasculitic neuropathy, especially when the observed section contains no vasculitic lesions.  相似文献   
60.
Mechanical stimulation is known to be an essential factor in the regulation of cartilage metabolism. We tested the hypothesis that expression of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) can be modulated by cyclic tensile stretch load in chondrocytes. Cyclic loading of repeated stretch stress at 10 cycles per minute with 10 kPa of stress for 6 h induced expression of LOX-1 to 2.6 times control in cultured bovine articular chondrocytes, equivalent to the addition of 10 microg/mL oxidized low density lipoprotein (ox-LDL) (2.4 times control). Application of the cyclic load to the chondrocytes along with 10 microg/mL ox-LDL resulted in synergistically increased LOX-1 expression to 6.3 times control. Individual application of cyclic loading and 10 microg/mL ox-LDL significantly suppressed chondrocytes viability (84.6% +/- 3.4% and 80.9% +/- 3.2% of control at 24 h, respectively; n = 3; p < 0.05) and proteoglycan synthesis [81.0% +/- 7.1% and 85.7% +/- 5.2% of control at 24 h, respectively; p < 0.05 when compared with 94.6% +/- 4.6% for native-LDL (n = 3)]. Cyclic loading and 10 microg/mL ox-LDL synergistically affected cell viability and proteoglycan synthesis, which were significantly suppressed to 45.6% +/- 4.9% and 48.7% +/- 6.7% of control at 24 h, respectively (n = 3; p < 0.01 when compared with individual application of cyclic loading or 10 microg/mL ox-LDL). In this study, we demonstrated synergistic effects of cyclic tensile stretch load and ox-LDL on cell viability and proteoglycan synthesis in chondrocytes, which may be mediated through enhanced expression of LOX-1 and which has important implications in the progression of cartilage degeneration in osteoarthritis.  相似文献   
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