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61.
Abstract

In recent years the acellular dermal matrix (ADM) has gained popularity in prosthetic breast reconstruction. These procedures involve placement of a closed suction drain in the reconstructed breast. Although it is now widely accepted that ADM has an overall positive effect on the outcome of breast reconstruction, data regarding its effect on postoperative drain secretions is lacking. This study was designed to quantitatively evaluate the influence of ADM on postoperative drain secretions in the setting of immediate prosthetic breast reconstruction (IPBR). This is a prospective, comparative controlled study. Two groups of 16 patients each underwent skin sparing mastectomies (SSM) and IPBR with or without ADM. Closed suction drains were left in all the reconstructed breasts and daily secretion volumes were recorded and compared. Postoperative complications were also noted. Patients in the ADM group showed higher daily and overall secretion volumes compared with patients in the control group (p = 0.014) and the time for removal of the drains was higher by an average of 5 days (13 compared with 8 days, respectively; p = 0.004). There was no correlation between ADM and infection. This study provides the first objective evidence that ADM contributes to elevated and prolonged drain secretions when used for IPBR. This might affect possible prosthesis-related complications (e.g., rotation and malposition, capsular contraction, seroma formation, and infection). This study also noted erythema of the post-mastectomy skin flaps in selected patients, which may be attributable to a local inflammatory reaction to the ADM rather than infection.  相似文献   
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Introduction: Topical delivery is defined as drug targeting to the pathologic sites of skin with the least systemic absorption. Drug localization in this case is a crucial issue. For these purposes vesicular drug delivery systems including niosomes, proniosomes, liposomes and transferosomes have been developed.

Areas covered: This review first highlights the role of niosome in dermatology focusing on localized skin delivery and then reviews the most recent literatures regarding specific applications of niosomal drug delivery systems in clinics.

Expert opinion: Niosomes are becoming popular in the field of topical drug delivery due to their outstanding characteristics like enhancing the penetration of drugs, providing a sustained pattern of drug release, increasing drug stability and ability to carry both hydrophilic and lipophilic drugs.  相似文献   
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A chemically extracted acellular allogeneic nerve graft can reduce postoperative immune rejection, similar to an autologous nerve graft, and can guide neural regeneration. However, it remains poorly understood whether a chemically extracted acellular allogeneic nerve graft combined with neurotrophic factors provides a good local environment for neural regeneration. This study investigated the repair of injured rat sciatic nerve using a chemically extracted acellular allogeneic nerve graft combined with ciliary neurotrophic factor. An autologous nerve anastomosis group and a chemical acellular allogeneic nerve bridging group were prepared as controls. At 8 weeks after repair, sciatic functional index, evoked potential amplitude of the soleus muscle, triceps wet weight recovery rate, total number of myelinated nerve fibers and myelin sheath thickness were measured. For these indices, values in the three groups showed the autologous nerve anastomosis group 〉 chemically extracted acellular nerve graft + ciliary neurotrophic factor group 〉 chemical acellular allogeneic nerve bridging group. These results suggest that chemically extracted acellular nerve grafts combined with ciliary neurotrophic factor can repair sciatic nerve defects, and that this repair is inferior to autologous nerve anastomosis, but superior to chemically extracted acellular allogeneic nerve bridging alone.  相似文献   
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Red grape (Vitis vinifera L.) flavonoids including flavan‐3‐ols (eg, catechin and epicatechin), flavonols (eg, quercetin) and anthocyanins (eg, malvidin) exert anti‐inflammatory and antioxidant activities. In the skin they also have a photoprotective action, and their effects have been extensively investigated in keratinocytes, melanocytes and fibroblasts. Despite their known effects also on blood vasculature, little is known on their activities on human dermal blood endothelial cells (HDBECs), which are critically involved in skin homeostasis as well as in the pathogenesis of neoplastic and inflammatory skin diseases. We sought to study the biological effects of selected red grape flavonoids in preventing the consequences of ultraviolet (UV)‐A irradiation in vitro. Our results show that red grape flavonoids prevent UV‐A‐induced sICAM‐1 release in HDBECs, suggesting that this cell type could represent an additional target of the anti‐inflammatory activity of flavonoids. In addition, flavonoids effectively inhibited UV‐A‐induced synthesis of collagen type III at both RNA and protein level, indicating that dermal blood microvasculature could be actively involved in ECM remodelling as a consequence of skin photo‐ageing, and that this can be prevented by red grape flavonoids.  相似文献   
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A series of laboratory experiments was carried out to assess transfer of liquids (vinegar) and powders (calcium acetate and magnesium carbonate) from hands, arms, gloves, respirators, clothing, and pens to the oral cavity or the perioral area (the area surrounding the mouth). Experiments were carried out with four volunteers. The donor area (the hands, arms, gloves, and so on) was loaded with a known mass of the test substance and was then brought into contact the receiver area (the oral cavity or the perioral area). The percentage of the substance on the donor that transferred to the receiver (the transfer efficiency or TE) was assessed using saliva samples and gauze wipes of the perioral area. Magnesium carbonate was measured on gauze and in saliva using inductively coupled plasma/atomic emission spectrometry. Calcium acetate and vinegar were measured using ion chromatography/electrochemical detection. Average transfer efficiencies were calculated for each substance and transfer scenario; these were compared using ANOVA and Kruskal-Wallis tests. Overall, direct transfer from the hands to the oral cavity was significantly higher (mean TE = 51.6) than indirect transfer from the hands to the oral cavity via the perioral area by licking the lips (mean TE = 11.5). The results suggested higher TEs for liquids than for solids and that hand-to-mouth TEs may increase with water solubility. Transfer from bare arms to the perioral area was higher than from arms covered by cotton sleeves for both liquids and powders. Although TE data are often required by models estimating exposure by inadvertent ingestion, relatively few published data are available. This study has provided evidence of some factors that may influence transfer of chemicals from hands or objects to the mouth (physical form, use of clothing, and so on) and has provided data that are essential for the development of predictive exposure models of inadvertent ingestion exposure.  相似文献   
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