جستجوی مقالات مرتبط با کلیدواژه « poly(3-hydroxybutyrate) » در نشریات گروه « پزشکی »

Poly(3-hydroxybutyrate) (PHB) is a well-known biodegradable polymer produced by some microorganisms and can be a suitable alternative for petrochemical plastics. PHB synthase encoded by phbC gene is the main enzyme in PHB biosynthesis pathway in Ralstonia eutropha. The aim of current study was the transformation of R. eutropha PTCC 1615 with its own phbC gene and evaluation of the overexpression effect on PHB accumulation.

DNA fragment including phbC gene and its promoter and terminator regions, was isolated from R. eutropha PTCC 1615, inserted into pET28a(+) vector, and transferred to the competent bacteria using calcium chloride and heat shock method. The effect of the cloned gene expression on PHB production was investigated with absorption of crotonic acid produced through PHB dehydration. Statistical analyses were carried out by SPSS software.

PHB content of cells of the engineered strain was 1.4 times more than that of the native bacteria. This significant difference can be an important finding for improvement of biopolymer production.

Overexpression of phbC, the critical gene in PHB biosynthesis pathway, in R. eutropha PTCC 1615 had considerable effect on PHB accumulation.

 Tissue engineering was an idea and today becomes a potential therapy for several tissues in dentistry such as Periodontal Disease and oral mucosa.

Periodontal regeneration is one of the earliest clinical disciplines that have achieved the therapeutic application of tissue engineering. The aim of the presence study was to prepare electrospun Poly(3-hydroxybutyrate) (PHB)/1% Carbon nanotubes (CNTs) scaffolds for periodontal regeneration.

1% w/v of CNTs was added to the polymer solutions and electrospinning. Physical properties of the scaffolds were evaluated by Scanning electron microscopy (SEM) and universal testing machine. Chemical characterization of the scaffolds was also assessed by Fourier-transform infrared spectroscopy (FTIR). Biological properties of the scaffolds were also evaluated in vitro by culturing periodontal ligament stem cells (PDLSCs) on the scaffolds for 10 days and in vivo by Implanting the scaffolds in rat model for 5 weeks.

Results showed that the scaffolds were mimicked fibrous connective tissue of the (PDL). CNTs improved the mechanical properties similar to 23-55 years old human PDL. In vitro biocompatibility study showed more attachment and proliferation of the PDLSCs for PHB/1%CNTs scaffolds compared to the PHB controls. In vivo study showed that CNTs in the scaffolds caused mild foreign body type giant cell reaction, moderate vascularization, and mild inflammation.

In conclusion, the results showed that the PHB/1%CNTs composite scaffolds may be potentially useful in periodontal regeneration.