| Wound and Bum infection, generally accounting for over 1/2 cases in Clinic, have long been regarded as a big problem in medical practice. Every year there are numerous patients who receive the relevant treatment in the hospitals. While dealing with it, it was discovered the favourable prognosis relies mostly on the effective control of the infection. Because once the infection occurs this condition can not only aggravate the wound scope but also result in the occurrence of septicemia . The infectious tissue around the area could provide an favourable environment for bacterial proliferation. In addition, the regional circulation is also damaged seriously. All of these factors hence contribute to impare penetration of the immune factors and antibiotics, and the efficacy of the general treatment. With respect to the external application of antibiotics, such as silver-zinic cream and some kinds of sulfadiazine drugs, long-term use has caused concern of severe kidney toxicity and leucocytopenia. On the other hand, the bacteria with antibiotics-resistance could emerge as a result of using such preparations .Taking a look at these problems, biological prevention deserves serious consideration, as it is really a brand-new sense and angle in medical repertoire. Firstly, it could avoid the inevitable disadvantages above mentioned, secondly, some extant similar applications which have been used clinically could give us the evidence and confidence in this field. This study is aimed at developing one biological preparation applied in wound treatment.In this study, at first step, we got one non-pathogenic mutant--BS9920 induced by UV and one kind of herb. After induction, BS9920 exhibits an enhanced antagonistic activity to three kinds of pathogens and exerts certain resistance to the herbal extract. Its biological and some molecular biological properties have been investigated.The preparation in this study mainly consists of one target mutant and one kind of herbal effective extract. The results obtained from adequate study in vitro and treatment on animal wound models have elucidated that this preparation does exert the obvious curative function on wound infection and could accelerate the wound heal. Compared with the other analogue preparation, it has certain advantage in practice. The preliminary study suggested the possible mechanisms were as follows: 1 Overgrowth of the BS9920 can form a biological protecting membrane.withstanding the aggression of exotic pathogenic bacteria. 2. Cooperating action of BS9920 itself with the herb extraction in anti-inflammation and accelerating the wound heal without obvious scar formed. The fundamental study also proved it is a safe, nontoxic and no side effect application. It could initiate neither the bacteremia nor the infection of the distant organ. It displayed a great potential in wound treatment as one new Probiotic Compound in the future.To enhance its efficacy in wound therapy, the biological property of the mutant strain was improved purposely at the molecular level. Firstly, the stable competent cell transforming system was established with B.subtilis?E.coli shuttle vector pHY07 and B.subtilis secretive vector pUS186. Secondly, the optimal transform factors have been screened out from a serial study.hEGF (human Epidermal Growth Factor) was selected as the target gene and introduced into BS9920. hEGF, also called Urogastrone, is one important growth factor in clinical diagnosis and treatment. hEGF could play a vital role in stimulating the growth and differentiation of epidermal cells and many other kinds of cells significantly. hEGF is a small 6kD polypeptide of about 170bp in size and mainly produced in Brunner's gland. hEGF gene was synthesized by PCR strategy. The sequencing result proved that the sequence of the synthesized fragment was totally identical with that of the published. Then it was cloned into the B.subtilis secretive vector-pUS 186 to construct recombinant plasmid pUSE. Subsequently, pUSE was introduced into BS9920. The recombinant c...
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