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Carboxyl single-walled carbon nanotubes (SWNTs) were used to construct an innovative drug delivery system by modification with chitosan (CHI) to enhance water solubility and biocompatibility.

Both the autologous nerve and ANAs rely on the permeation of tissue fluids to supply nutrients during the early stage, and microvessel growth mainly starts at both ends of the graft and enters the graft along the long axis. Compared to ANAs, the growth speed of revascularization in autologous nerve grafts was faster, leading to a better outcome in the autologous nerve group.

Diabetic foot ulcers (DFU), which may lead to lower extremity amputation, is one of the severe and chronic complications of diabetic mellitus. This study aims to develop, and use dressings based on Silk fibroin (SF) as the scaffold material, gelatin microspheres (GMs) as the carrier for the neurotensin (NT), a neuropeptide that acts as an inflammatory modulator in wound healing and NT as accelerate wound healing drug to treat DFU. We evaluated the wound healing processes and neo-tissue formation in rat diabetic model by macroscopic observation, histological observation (H&E staining and Masson's trichrome staining) and immunofluorescence analysis at 3, 7, 14, 21 and 28 post-operation days. Our results show that the NT/GMs/SF group performance the best not only in macroscopic healing and less scars in 28 post-operation days, but also in fibroblast accumulation in tissue granulation, collagen expression and deposition at the wound site. From release profiles, we can know the GMs are a good carrier for control release drugs. The SEM results shows that the NT/GMs/SF dressings have an average pore size are 40–80 μm and a porosity of ∼85%, this pore size is suit for wound healing regeneration. These results suggest that the NT/GMs/SF dressings may work as an effective support for control release NT to promote DFU wound healing.

Aim: To examine the effect of venom from the spider Macrothele raven on cell proliferation and cytotoxicity in human cervical carcinoma, HeLa cells. Methods: Morphological and biochemical signs of apoptosis appeared using acridine orange-ethidium bromide (AO/EB) staining. Marked morphological changes in HeLa cells after treatment with spider venom were observed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Cell proliferation and cytotoxicity were determined by [methyl-3 H] thymidine assay ([ 3 H]TdR) and lactate dehydrogenase (LDH) release, respectively. DNA fragmentation and cell cycle distribution were monitored using flow cytometry. In addition, Western blot analysis was used to evaluate the level of caspase-3 expression. In vivo examination of the inhibition of the size of tumors in nude mice treated with spider venom was measured. Results: Marked morphological changes were observed using AO/EB staining, SEM and TEM assay. Spider venom at concentrations of 10-40 mg/L caused dose-and time-dependent inhibition of HeLa cell proliferation. The ratio of apoptosis and necrosis increased. The activity of caspase-3 was upregulated after spider venom treatment. In vivo study of tumor size revealed that tumors significantly decreased in size from controls to tumors treated for 3 weeks with spider venom (P<0.05). Conclusion: The inhibition of HeLa cells by the venom of the spider Macrothele raveni was carried out in three ways: induction of apoptosis, necrosis of toxicity damage and direct lysis. Spider venom is a novel anti-tumor material both in vitro and in vivo.

BackgroundAlignment of RNA secondary structures is important in studying functional RNA motifs. In recent years, much progress has been made in RNA motif finding and structure alignment. However, existing tools either require a large number of prealigned structures or suffer from high time complexities. This makes it difficult for the tools to process RNAs whose prealigned structures are unavailable or process very large RNA structure databases.ResultsWe present here an efficient tool called RSmatch for aligning RNA secondary structures and for motif detection. Motivated by widely used algorithms for RNA folding, we decompose an RNA secondary structure into a set of atomic structure components that are further organized by a tree model to capture the structural particularities. RSmatch can find the optimal global or local alignment between two RNA secondary structures using two scoring matrices, one for single-stranded regions and the other for double-stranded regions. The time complexity of RSmatch is O(mn) where m is the size of the query structure and n that of the subject structure. When applied to searching a structure database, RSmatch can find similar RNA substructures, and is capable of conducting multiple structure alignment and iterative database search. Therefore it can be used to identify functional RNA motifs. The accuracy of RSmatch is tested by experiments using a number of known RNA structures, including simple stem-loops and complex structures containing junctions.ConclusionWith respect to computing efficiency and accuracy, RSmatch compares favorably with other tools for RNA structure alignment and motif detection. This tool shall be useful to researchers interested in comparing RNA structures obtained from wet lab experiments or RNA folding programs, particularly when the size of the structure dataset is large.