Poor blood circulation makes it difficult for antitubercular drugs to achieve effective bactericidal concentration at tuberculose focus. The residual Mycobacterium tuberculosis around surgical wound would multiply, resulting in nonunion or sinus formation. Carbon nanotubes have strong tissue penetration and can cross many kinds of physiological barriers. Here, we constructed a chitosan/carbon nanotubes nanoparticles to control slow release of isoniazid. Transmission electron microscopy and nanoparticle tracking and analysis results showed that the diameter of chitosan/carbon nanotubes nanoparticles was between 150 and 250 nm. Chitosan/carbon nanotubes nanoparticles significantly prolonged the release time of isoniazid, and the release rate was more uniform, no sudden release was observed. In vitro experiments showed that chitosan/carbon nanotubes nanoparticles did not destroy biological function of isoniazid, but could reduce its cytotoxicity and inflammation. We further constructed animal model of tuberculous ulcer. The results showed that isoniazid/chitosan/carbon nanotubes nanoparticles promoted the healing of tuberculosis ulcer. Compared with isoniazid group and isoniazid/carbon nanotubes group, the area of wounds decreased by 94.6% and 89.8%, respectively. Immunohistochemistry showed that CD3+ and CD4+ T cell number decreased significantly in isoniazid/chitosan/carbon nanotubes group. In conclusion, we constructed a kind of isoniazid/chitosan/carbon nanotubes nanoparticles, which can significantly promote the healing of tuberculosis ulcer. Our study provided an effective way for the treatment of secondary wound healing of bone tuberculosis.

Objective: To investigate the effect of MicroRNA-146a modified adipose-derived stem cell exosomes on the proliferation and migration of fibroblasts and the therapeutic effect on wound healing. Methods: Culture and identification of human adipose-derived stem cells (hASCs), miRNA-146a minic vector was constructed and transfected into hASCs, the exosomes of the empty group and overexpression group were extracted, identified, and quantitatively analyzed after 24 h of successful transfection. The exosomes were added into National Institute of Health Mouse Embryonic Fibroblasts (NIH/3T3) and cultured for 48 h, the proliferation and migration ability of NIH/3T3 fibroblasts was detected. The expression of serpin family H member 1 (SERPINH1) and phosphorylated extracellular regulated protein kinase (p-ERK) was detected by Western blot. The model of back wound was established. The exosomes were injected into 4 different sites with the shape of “cross” around the wound, and the scar diameter of the skin defect was measured at 3, 7, and 11 days, the skin of the defect was taken on the 14th day. platelet endothelial cell adhesion molecule-1 (CD31) was detected by immunofluorescence staining to evaluate angiogenesis, and Western blot was used to detect the expression of SERPINH1 and p-ERK. Results: The miR-146a mimic-exosome promoted the proliferation and migration of fibroblasts, and the expression of SERPINH1 and p-ERK2 was up-regulated. After the rats were treated with exosomes, the wound area decreased rapidly, neovascularization was promoted, and the expression of SERPINH1 and p-ERK2 was up-regulated. Conclusions: MicroRNA-146a modified adipose stem cell exosomes could regulate the expression of SERPINH1 and p-ERK, promote the migration and proliferation of fibroblasts, and neovascularization to promote the wound healing of rat back.

A new nanocatalyst has been synthesized by confining magnetic nickel nanoparticles within carbon nanotubes (CNTs) and characterized by XRD, TEM, Raman and VSM. The character of the nanocatalyst passivated with a gas mixture was that it can be stored safely in air below 150 C and needs no activation prior to use. In the catalytic test, a nickel oxide nanocatalyst confined inside the Multi-walled carbon nanotubes nanochannels (NiO/MWCNTs-in) was found to be a highly efficient and reusable catalyst for the reduction of various aromatic nitro compounds to various aromatic amines, the conversion and selectivity of which were almost up to 100% and exceed 80%. The prominent merit of the catalyst is that the overall formation rate of product inside the nanotubes exceeds that outside. Moreover, it is inexpensive, and could be prepared and scaled up easily. Besides, it can be simply separated from the reaction mixtures by an external magnetic field As a result of the possible confinement effect of CNTs, the employment of the CNTs channels as nanoreactors for catalysis may provide opportunities for the development of new heterogeneous catalysts.

Poly(ɛ‐caprolactone) (PCL)/gelatin (GE) nanofiber scaffolds with varying concentrations of lanthanum chloride (LaCl3, from 0 to 25 mM) were fabricated by electrospinning. The scaffolds were characterized by scanning electron microscopy, contact angle and porosity measurements, mechanical strength tests, and in vitro degradation studies. In vitro cytotoxicity and cell adhesion and proliferation studies were performed to assess the biocompatibility of the scaffolds, and in vivo wound healing studies were conducted to assess scaffold applications in the clinic. All prepared scaffolds were noncytotoxic, and the growth of adipose tissue–derived stem cells on LaCl3‐containing scaffolds was better than on the pure PCL/GE scaffold. Cell proliferation studies showed the greatest cell growth in the PCL/GE/LaCl3 scaffolds. Further, in vivo studies proved that the PCL/GE/LaCl3 scaffolds can promote wound healing. The results suggest that nanofiber scaffolds containing LaCl3 promote cell proliferation and have good biocompatibility, and thus potential for application in the treatment of skin wounds. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46672.