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INTRODUCTION: Topical agents typically remain in the wound site for time duration that are too short to effectively eradicate MRSA tradition formation of BZK that can be maintained within the wound site for longer time periods, should be more effective. METHODS: The novel chitosan and poly (D,L-lactide-co-glycoside) nanoparticles loaded with benzalkonium bromide (BZK) were designed, for the promotion wound healing after MRSA infection. The physical characterization of these nanoparticles, as well as their antibacterial activity in vitro, release profile in simulated wound fluid, cell toxicity, anti-biofilm activity, and their ability to improve the skin wound healing in a mouse model were also studied. RESULTS: These novel nanoparticles were found to have a significant antibacterial activity (p<0.01), both in vitro and in vivo test. The stronger anti-biofilm ability of the nanoparticles to inhibit the formation of bacterial biofilms, at a concentration of 3.33 µg/mL, and clear existing bacterial biofilms, at a concentration of 5 mg/mL, compared with its water solution. In addition, significant damage to bacterial cell walls also was found, providing insight into the mechanism of antibacterial activity. CONCLUSION: Taken together, these results demonstrated the ability of BZK-loaded nanoparticles in the promotion of skin wound healing with MRSA infection. The current findings open a new avenue for nanomedicine development and future clinical applications in the treatment of wounds.

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BACKGROUND: Aloe-emodin is reported as a potential cancer therapeutic agent due to its inhibition of the proliferation, migration, and invasion of cancer cells. This study aimed to confirm the effects of aloe-emodin on the progression of melanoma and identify the underlying molecular mechanisms. METHODS: The effects of aloe-emodin treatment (concentrations ranging from 0 to 25 µg, 48 h) on proliferation, apoptosis, distribution of cell cycle, migration, and invasion were detected by performing Cell Counting Kit-8 (CCK-8) assay, colony formation assay, flow cytometry, wound healing assay, and Transwell invasion experiments. Rescue experiments were carried out by overexpression of ß-catenin to verify the role of ß-catenin in the inhibition of melanoma by aloe-emodin. The analysis was carried out at the animal level by constructing tumor-bearing nude mice model. RESULTS: The results showed that aloe-emodin prominently reduced the proliferation, migration, and invasion of melanoma cells. Additionally, it was found that aloe-emodin significantly enhanced the cell apoptosis and induced G2 phase arrest of melanoma cells via enhancing the expressions of cleaved-caspase3, bax, and reducing cyclinD1, c-myc, and bcl-2. In addition, aloe-emodin could also inhibit Wnt3a levels, and promote GSK3-beta and beta-catenin phosphorylation. In vivo experiments also showed that overexpression of beta-catenin reversed the effects of aloe-emodin on tumor growth. CONCLUSIONS: In conclusion, our findings indicated that aloe-emodin might prominently inhibit the tumor growth and metastasis of melanoma via the Wnt/beta-catenin signaling pathway in vitro. Therefore, aloe-emodin may serve as a potential drug for the clinical treatment of melanoma.

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Cultured skin has been used extensively for testing therapeutic drugs because it replicates the physical and biochemical properties of whole skin. However, traditional static culture cannot fully maintain cell viability and skin morphology because of the limitations involved with nutrient transmission. Here, we develop a new dynamic perfusion platform for skin culture and compare it with a static culture device. Rat skins were cultured in either static or dynamic condition for 0, 3, 6, 9 and 12 days. H&E, periodic acid-Schiff (PAS) and picrosirius red (PSR) staining were used for skin morphology detection, immunostaining against cytokeratin 10 (CK10) for differentiation detection, immunostaining against proliferating cell nuclear antigen (PCNA) for cell proliferation detection and TUNEL staining for apoptosis detection. After culturing for 12 days, the epidermis, basement membrane, hair follicles and connective tissue were disrupted in the static group, whereas these features were preserved in the dynamic group. Moreover, compared to the static group, proliferation in the epidermis and hair follicles was significantly improved and apoptosis in dermis was significantly decreased in the dynamic group. These findings suggest that our device is effective for extending the culture period of rat skin to maintain its characteristics and viability in vitro.

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Helicobacter pylori has infected more than half of the world's population, causing gastritis, gastric ulcers, gastric mucosa-associated lymphoid tissue lymphoma and gastric cancer. The oral recombinant Helicobacter pylori vaccine currently used has made great progress in addressing this problem, however, its efficacy and longevity still need to be improved. Th1 and Th17 cells play essential roles in local protection against Helicobacter pylori in the stomach mucosa. Additionally, protective immunodominant antigens are the preferred for a vaccine. In this work, Helicobacter pylori whole cell lysate was separated into 30 groups based on molecular weight by molecular sieve chromatography. The group best promoting CD4 T cells proliferation was selected and evaluated by immunization. The detail proteins were then analyzed by LC-MS/MS and expressed in Escherichia coli. Eleven proteins were selected and the dominant ones were demonstrated. As a result, three protective immunodominant antigens, inosine 5'-monophosphate dehydrogenase, type II citrate synthase, and urease subunit beta, were selected from Helicobacter pylori whole cell. Two of them (inosine 5'-monophosphate dehydrogenase and type II citrate synthase) were newly identified, and one (urease subunit beta) was confirmed as previously reported. The mixture of the three antigens showed satisfactory protective efficiency, with significant lower H. pylori colonization level (P < 0.001) and stronger Th1 (P < 0.001) and Th17 (P < 0.001) responses than PBS control group. Thus, inosine 5'-monophosphate dehydrogenase, type II citrate synthase, and urease subunit beta are three protective antigens inducing dominant Th1 and Th17 responses to defend against Helicobacter pylori infection.

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BACKGROUND: Helicobacter pylori (H. pylori) seem to involve in the etiology of chronic spontaneous urticaria (CSU). But studies of the pathogenic mechanism are very little. METHODS: In this study, we detected the serum-specific anti-H. pylori IgG and IgE antibodies in 211 CSU and 137 normal subjects by enzyme-linked immunosorbent assay (ELISA), evaluated the direct activation effects of H. pylori preparations and its protein components on human LAD2 mast cell line in vitro, and analyzed the specific protein ingredients and functions of the most effective H. pylori mixed protein component using liquid chromatography-mass spectrometry and ELISA assay. RESULTS: In CSU patients, the positive rate of anti-H. pylori IgG positive rate was significantly higher than that in normal controls, and the anti-H. pylori IgE levels had no statistical difference between H. pylori-infected patients with and without CSU. Further studies suggested that H. pylori preparations can directly activate human LAD2 mast cell line in a dose-dependent manner and its most powerful protein component was a mixture of 21-35 kDa proteins. Moreover, the 21-35 kDa mixed protein component mainly contained 23 kinds of proteins, which can stimulate the release of histamine, TNF-a, IL-3, IFN-γ, and LTB4 by LAD2 cells in a dose-dependent or time-dependent manner. CONCLUSIONS: A 21-35 kDa mixed protein component should be regarded as the most promising pathogenic factor contributing to the CSU associated with H. pylori infection.

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Hair follicles undergo cyclical growth and regression during postnatal life. Hair regression is an apoptosis-driven process strictly controlled by micro- and macro-environmental signals. However, how these signals are controlled remains largely unknown. Hoxc13, a member of the Hox gene family, is reported to play an important role in hair follicle differentiation. In the present study, we observed that Hoxc13 was highly expressed in the outer root sheath, matrix, medulla and inner root sheath of hair follicles in a hair cycle-dependent manner. We therefore investigated the role of Hoxc13 in hair follicle cycling. Injection of ShRNA (ShHoxc13) to suppress Hoxc13 in early anagen promoted premature catagen entry, shown by significantly decreased hair length and hair bulb size, increased percentage of catagen hair follicles, hair cycle score and TUNEL+ cells and inhibited proliferation. In contrast, local injection of recombinant Hoxc13 polypeptide (rhHoxc13) during the late anagen phase prolonged the anagen phase. Additionally, rhHoxc13 injections during the telogen phase significantly promoted hair growth and induced the anagen progression. At the molecular level, the expression of phosphorylated smad2 (p-smad2), a key factor of active TGF-ß1 signaling, was up-regulated in the ShHoxc13-treated hair follicles and down-regulated in rhHoxc13-treated hair follicles, suggesting that Hoxc13 might block anagen-catagen transition by inhibiting the TGF-ß1 signaling. Taken together, our data strongly suggest that Hoxc13 is a novel and crucial regulator of the hair cycle. This might also provide an understanding of the mechanism of the 'hair cycle clock' and the development of alopecia treatments.

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