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991.
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994.
Facial nerve palsy is a condition with several implications, particularly when occurring in childhood. It represents a serious clinical problem as it causes significant concerns in doctors because of its etiology, its treatment options and its outcome, as well as in little patients and their parents, because of functional and aesthetic outcomes. There are several described causes of facial nerve paralysis in children, as it can be congenital(due to delivery traumas and genetic or malformative diseases) or acquired(due to infective,inflammatory, neoplastic, traumatic or iatrogenic causes). Nonetheless, in approximately 40%-75% of the cases, the cause of unilateral facial paralysis still remains idiopathic. A careful diagnostic workout and differential diagnosis are particularly recommended in case of pediatric facial nerve palsy, in order to establish the most appropriate treatment, as the therapeutic approach differs in relation to the etiology.  相似文献   
995.
In this paper was demonstrated that umbelliferone induces changes in structure and pharmacological activities of Bn IV, a lysine 49 secretory phospholipase A2 (sPLA2) from Bothrops neuwiedi. Incubation of Bn IV with umbelliferone virtually abolished platelet aggregation, edema, and myotoxicity induced by native Bn IV. The amino acid sequence of Bn IV showed high sequence similarities with other Lys49 sPLA2s from B. jararacussu (BthTx-I), B. pirajai (PrTx-I), and B. neuwiedi pauloensis (Bn SP6 and Bn SP7). This sPLA2 also has a highly conserved C-terminal amino acid sequence, which has been shown as important for the pharmacological activities of Lys49 sPLA2. Sequencing of Bn IV previously treated with umbelliferone revealed modification of S(1) and S(20). Fluorescent spectral analysis and circular dichroism (CD) studies showed that umbelliferone modified the secondary structure of this protein. Moreover, the pharmacological activity of Bn IV is driven by synergism of the C-terminal region with the α-helix motifs, which are involved in substrate binding of the Asp49 and Lys49 residues of sPLA2 and have a direct effect on the Ca2+-independent membrane damage of some secretory snake venom PLA2. For Bn IV, these interactions are potentially important for triggering the pharmacological activity of this sPLA2.  相似文献   
996.
Loss of volume in the temple can result in a gaunt, wasted appearance. Dermal filler augmentation of the temples can counteract volume loss and achieve a more balanced and youthful appearance. Although the temporal fossa is a critical area for volume restoration of the aging face, published information is limited. The authors retrospectively describe the treatment of 20 female patients who sought facial rejuvenation and received small gel particle hyaluronic acid (SPG-HA) injections for temporal fossa augmentation. The authors discuss a rationale for their choice of dermal filler and provide a detailed, illustrated injection technique guide for restoring volume in the temporal fossa region with SPG-HA. There is a need for prospective, controlled studies investigating safety, efficacy and persistency of hyaluronic acid fillers in this area of the face.  相似文献   
997.
Multicompartment nanoscopic carriers can be easily assembled by inducing the aggregation of anionic "hybrid" niosomes by means of cationic biocompatible polyelectrolytes. The resulting vesicle clusters, whose size and overall net charge can be easily controlled by varying the polyelectrolyte-to-particle charge ratio, show an interesting potential for multidrug delivery. In this article we provide strong evidence for their effective use in vitro as multicompartment vectors selectively directed toward monocyte/macrophage cells, showing that the monocyte/macrophage-mediated activation of Tγδ lymphocytes induced by zoledronic acid is enhanced by a factor 10(3) when the zoledronic acid is intracellularly delivered through these carriers. Furthermore, the multicompartment ?-polylysine niosome clusters, with their intrinsic selectivity toward macrophages, appear particularly suitable for implementing therapeutic strategies against chronically infected macrophages. FROM THE CLINICAL EDITOR: ?-polylysine niosome clusters, with their intrinsic selectivity toward macrophages, offer the potential for multidrug delivery. The effectiveness of aminobisphosphonate zoledronate is demonstrated to enhance the recruitment of Tγδ lymphocytes by macrophages by 2 orders of magnitude, suggesting a new therapeutic strategy for addressing pathologies featuring chronically infected macrophages.  相似文献   
998.
Mechanistic study of biological processes via Quantum Dots (QDs) remain constrained by inefficient QD delivery methods and consequent altered cell function. Here the authors present a rapid method to label activated receptor populations in live cancer cells derived from medulloblastoma and glioma tumors. The authors used QDs to bind the extracellular domain of Epidermal Growth Factor Receptor (EGF-R) proteins and then induced receptor activation to facilitate specific detection of intracellular, activated EGF-R subpopulations. Such labeling enables rapid identification of biological markers characteristic of tumor type, grade and chemotherapy resistance. FROM THE CLINICAL EDITOR: In this paper, a rapid, quantum dot-based method is presented with the goal of labeling activated receptor populations in live cancer cells. More accurate characterization of medulloblastoma and glioma cancer cells using this biomarker detection technique may lead to a more specific targeted therapy.  相似文献   
999.
Poorly differentiated tumors in non-small cell lung cancer (NSCLC) have been associated with shorter patient survival and shorter time to recurrence following treatment. Here, we integrate multiple experimental models with clinicopathologic analysis of patient tumors to delineate a cellular hierarchy in NSCLC. We show that the oncofetal protein 5T4 is expressed on tumor-initiating cells and associated with worse clinical outcome in NSCLC. Coexpression of 5T4 and factors involved in the epithelial-to-mesenchymal transition were observed in undifferentiated but not in differentiated tumor cells. Despite heterogeneous expression of 5T4 in NSCLC patient-derived xenografts, treatment with an anti-5T4 antibody-drug conjugate resulted in complete and sustained tumor regression. Thus, the aggressive growth of heterogeneous solid tumors can be blocked by therapeutic agents that target a subpopulation of cells near the top of the cellular hierarchy.  相似文献   
1000.

Objective

Degradation of hybrid layers (HLs) within resin-infiltrated dentine results from multiple degradation factors, including collagenolytic activity of specific matrix metalloproteinases (MMPs). Inhibition of host-derived MMPs may, therefore, slow the degradation of HL. The null hypothesis tested is that the presence of MMP-2 is similar regardless of chlorhexidine (CHX) pre-treatment or the use of an adhesive.

Methods

Powdered dentine prepared from extracted human teeth was divided into 4 groups: (G1) mineralised powder (control group); (G2) dentine powder treated with 1% phosphoric acid for 1 min; (G3) 1% phosphoric acid-etched dentine treated with Adper Scotchbond 1 XT (SB1XT; 3M ESPE); (G4) 1% phosphoric acid-etched dentine treated with 0.2% CHX followed by SB1XT. The concentration of detectable pro-MMP-2 and MMP-2 was assayed using a colorimetric assay system (QuantiSir). In addition, the presence of MMP-2 in the HL was assessed in 1 year-aged adhesive-dentine interfaces using an immunohistochemical approach under FEI-SEM/TEM.

Results

In dentine powder treated with 1% phosphoric acid (G2), MMP-2 level decreased compared to controls (G1); the application of SB1XT (G3) resulted in an increase of MMP-2, whilst 0.2% CHX before SB1XT application (G4), reduced MMP-2. The FEI-SEM/TEM analysis revealed MMP-2 distribution within the HL of aged interfaces showing increase MMP-2 patterns in the control group and minor labelling in the CHX-pretreated specimens.

Conclusion

The results of this study support the use of non-toxic MMPs inhibitors, such as CHX, as an appropriate additional step in bonding procedures in order to increase the longevity of the adhesive restorations.  相似文献   
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