ABSTRACT
Bone defects have always been an important cause of threat to human health, and artificial biomimetic bone repair replacement materials are currently one of the most effective and feasible solution approaches to treat bone damage. To develop artificial bone biomimetic materials, an in vitro biomimetic mineralization system must be constructed first to study in vitro biomimetic mineralization mechanism of natural bone matrix. Collagen is a template for mineralization, and its properties such as crosslinking degree, diameter, osmotic pressure, and surface charge can all directly affect mineralization progress. The biochemical and mechanical environments in which mineralization occurs are also quite distinct in their effects on mineralization process, particularly noncollagenous proteins and fluid shear stress (FSS). FSS is considered to be the main mechanical stimulation of bone tissues in micro-environment, which is of great significance to bone growth, repair and health maintenance. FSS at different levels and loading regimes has significant effects on transformation of amorphous calcium phosphate to bone apatite, self-assembly and directional alignment of collagen fibrils, and formation of hierarchical intrafibrillar mineralization. In this paper, the factors affecting collagen mineralization and their mechanism were summarized, with focus on regulation of FSS on collagen mineralization, and development direction in future was also prospected.
ABSTRACT
In recent years, researchers have become more interested in fish scrap collagen collection .Fish collagen, thanks to its low antigenic and hypoallergenic properties , is superior to that of higher animals .Meanwhile , fish collagen derives from a wealth of sources and has a moderate price .Based on recent fish collagen extraction and modification , this article summarizeds extraction technologies , such as hot-water, chemistry, bio-enzyme, compound extraction and such modification methods as physical and chemical processes to improve the thermal stability .
ABSTRACT
Objective To sum up clinical experiences of intractable temporal lobe epilepsy by microsurgery. Methods A retrospective review was conducted in 50 cases with epilepsy,and temporal lobe was resected by microsurgery from June 1996 to Oct. 2003. Results Follow-up patients from six months to five years.The follow up showed healing outcome in 25 cases,good results in 13 cases,unsatisfactory outcome in 9 cases,no improvement in 3 cases.Slight paresis 6 cases,divagation 8 cases,psychosis 5 cases and no death case. Conclusions Application of microsurgery can obvously improve the clinical result of patients with temporal lobe epilepsy and decrease the complication after operation.