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The spinal perineurial cyst (Tarlov) is a dilatation between the perineurium and endoneurium of spinal nerve roots, located at level of the spinal ganglion and filled with cerebrospinal fluid but without communication with the perineurial subarachnoid space. The aim of the study was to evaluate it incidence among East-European patients. The retrospective data collected during various magnetic resonance spinal examinations and stored on the picture archiving and communication system was analyzed for an incidence of perineurial cysts. From among 842 patients that underwent examination, 75 cases perineurial cysts were revealed. In 22 cases single anomalies were found. In remaining 53 cases, multiple uni- or less frequently bilateral changes were noted. The most common position was the sacral canal, particularly the level of S2 and S3. Occasionally, cysts were also visible on the cervical, thoracic and lumbar level. Incidence of sacral perineurial cysts was significantly higher in females than in males. Similar data was found for single and multiple changes despite of their localization. Insignificant changes were seen for patient age and cyst size. Perineurial spinal cysts were the most frequently observed on the sacral level and such changes were more common in females.  相似文献   
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Mast cells are a critical first line of defense against endogenous and environmental threats. Their participation in innate immunity is well characterized; activation of toll like receptors as well as receptors for complement, adenosine, and a host of other ligands leads to mast cell release of preformed mediators contained within granules along with newly synthesized arachidonic acid metabolites, cytokines, and chemokines. These confer protective effects including the induction of mucus secretion, smooth muscle contraction, and activation of common itch and pain sensations, all of which act to promote expulsion of noxious agents. While their innate immune role as sentinel cells is well established, recent research has brought into focus their separate but also critical function in adaptive immunity particularly in the setting of IgE mediated food allergies. Crosslinking of FcεR1, the high affinity receptor for IgE, when bound to IgE and antigen, triggers the release of the same factors and elicits the same physiologic responses that occur after activation by innate stimuli. Though IgE-activated mast cells are best known for their role in acute allergic reactions, including the most severe manifestation, anaphylaxis, accumulating evidence has suggested an immunoregulatory effect in T cell-mediated immunity, modulating the balance between type 2 immunity and tolerance. In this review, we outline how mast cells act as adjuvants for food antigen driven Th2 cell responses, while curtailing Treg function.  相似文献   
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Matrix metallopeptidase 2 (MMP-2) and matrix metallopeptidase 9 (MMP-9) are involved in the breakdown of extracellular matrix in normal physiological processes as well as in disease processes, such as cancer metastasis. We conducted this work to study the role of MMP-2 and MMP-9 in breast cancer by measuring their plasma concentrations before and after surgery. Also, to examine if their levels can reflect the stage of disease and prognosis. Forty-eight breast cancer patients and 13 patients with benign breast diseases were included in the study. MMP-2 and MMP-9 levels were measured by ELISA and semi-quantitative real-time PCR. MMP-2 and MMP-9 levels in plasma were determined by ELISA immediately before surgery and during 6 to 12 months after curative surgery. We observed a significant increase in the level of MMP-9 mRNA expression in breast cancer patients in comparison to their normal breast tissues and to tissues of benign breast disease. In all TNM tumor stages, the plasma levels of MMP-2 and MMP-9 were increased significantly before curative surgery in the studied patients with breast carcinoma and decreased significantly after surgery. Both MMP-2 and MMP-9 may be used as a possible marker for follow-up or as a marker that reflects the response of the disease to treatment.

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Genetic variations of microRNA encoding genes influence various sorts of diseases by modifying the expression or activity of microRNAs. MicroRNA 146a is an epigenetic regulator of immune response through controlling the type I interferon (IFN) and nuclear factor kappa B (NF-κB) pathways. Genetic variations of microRNA 146a impact the susceptibility to systemic lupus erythematosus (SLE) and its clinical presentations. This study aimed to investigate the polymorphisms of microRNA-146a gene (rs2431697 and rs57095329) in patients with SLE and its association with disease activity. Sixty-five patients with SLE and 40 apparently healthy controls were enrolled in this study. Patients were subjected to history taking, clinical examination, and disease activity evaluation by SLEDAI score. The microRNA-146a variants were determined by allele discrimination real-time PCR method in all participants. We found a statistically significant association between rs2431697 T allele and SLE (P-value?<?0.05), but there was no significant association between rs57095329 and SLE. The T/T genotype of microRNA-146a rs2431697 was associated with lupus nephritis, higher disease activity, and autoantibodies production. The microRNA-146a rs2431697 T allele could be a potential risk factor that contributes to SLE susceptibility, development of lupus nephritis, and disease activity.

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137.
In vitro tissue engineering is emerging as a potential tool to meet the high demand for replacement tissue, caused by the increased incidence of tissue degeneration and damage. A key challenge in this field is ensuring that the mechanical properties of the engineered tissue are appropriate for the in vivo environment. Achieving this goal will require detailed understanding of the interplay between cell proliferation, extracellular matrix (ECM) deposition and scaffold degradation. In this paper, we use a mathematical model (based upon a multiphase continuum framework) to investigate the interplay between tissue growth and scaffold degradation during tissue construct evolution in vitro. Our model accommodates a cell population and culture medium, modelled as viscous fluids, together with a porous scaffold and ECM deposited by the cells, represented as rigid porous materials. We focus on tissue growth within a perfusion bioreactor system, and investigate how the predicted tissue composition is altered under the influence of (1) differential interactions between cells and the supporting scaffold and their associated ECM, (2) scaffold degradation, and (3) mechanotransduction-regulated cell proliferation and ECM deposition. Numerical simulation of the model equations reveals that scaffold heterogeneity typical of that obtained from $\mu $ CT scans of tissue engineering scaffolds can lead to significant variation in the flow-induced mechanical stimuli experienced by cells seeded in the scaffold. This leads to strong heterogeneity in the deposition of ECM. Furthermore, preferential adherence of cells to the ECM in favour of the artificial scaffold appears to have no significant influence on the eventual construct composition; adherence of cells to these supporting structures does, however, lead to cell and ECM distributions which mimic and exaggerate the heterogeneity of the underlying scaffold. Such phenomena have important ramifications for the mechanical integrity of engineered tissue constructs and their suitability for implantation in vivo.  相似文献   
138.
Cymbopogon citratus and Eucalyptus citriodora are widely used herbs/plants as a source of ethnomedicines in tropical regions of the world. In this work, we studied the anti-inflammatory and gastroprotective effects of C. citratus and E. citriodora essential oils on formol-induced edema, and acetic acid induced abdominal cramps in Wistar rats. To fully understand the chemically induced anti-inflammatory properties of these plants, we first analyzed the chemical composition of the essential oils. A total of 16 chemical constituents accounting for 93.69 % of the oil, were identified in C. citratus among which, Geranial (27.04 %), neral (19.93 %) and myrcene (27.04 %) were the major constituents. For E. citriodora, 19 compounds representing 97.2 % of the extracted oil were identified. The dominant compound of E. citriodora essential oil was citronellal (83.50 %). In vivo analysis and histological assay showed that the two essential oils displayed significant dose dependent edema inhibition effect over time. They displayed strong analgesic and antipyretic properties similar to that induced by 50 mg/kg of acetylsalicylate of lysine. However, the E. citriodora essential oil was more effective than that of C. citratus. We identified significant numbers of aldehyde molecules in both essential oils mediating antioxidant activity that may contribute to the anti-inflammatory effects observed on the rats. Altogether, this work demonstrates the anti-inflammatory property of C. citratus and E. citriodora suggesting their potential role as adjuvant therapeutic alternatives in dealing with inflammatory-related diseases.  相似文献   
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Nummulites beaumonti d'Archiac & Haime, 1853, originally described from El Basatin, Gebel Mokattam, Greater Cairo, is redefined from a nummulitic bank at the base of the Maadi Formation from its type locality as neotype. Schaub (1981) described the species from Libya and the type example of this species is still unknown. N. discorbinus Schlotheim (1820) is described as neotype from a nummulitic bank in the Mokattam Formation, which is located in the site of the Citadel tombs, near the Salah El Din Citadel, Gebel Mokattam, Egypt. According to Schaub (1981), the type example of this species is also unknown. For this reason the establishment of the neotypes of these two widespread nummulites species: N. discorbinus (Late Lutetian) and N. beaumonti (Bartonian) is important and tackled in this paper. N. qurnensis n. sp. ( = N. sp. cf. beaumonti in Boukhary et al. 2002) is introduced as a new species from the lower Bartonian part of the Qurn Formation of Helwan. Biometrical studies are carried out on the three species to present up to date information on these Nummulites, with particular attention to their biostratigraphic correlation with the Shallow Benthic Zones (SBZ) of Serra-Kiel et al. 1998. The authors would like to stress the importance of a careful designation of a neotype to avoid the introduction of complicated and unnecessary taxonomic problems.  相似文献   
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