Faced with huge demand for building public health capacity in the post-Ebola era, Africa Union has planned to establish Africa Center for Disease Control and Prevention ( Africa CDC,ACDC), with headquarters in Addis Ababa, Ethiopia, and at least 5 regional collaborating centers in each region of the continent .The strategic objectives of ACDC focus on building a continental integrated public health system and strengthening needed public health capacity .The current study analyzed the background , plans, development layout and strategy of ACDC , and provided references for China-Africa cooperation in the areas of public health and for the formulation of China global strategies of biosecurity and disease prevention and control .

100% elevation of PKC activity in the retina, and administration of D ? tocopherol prevented the elevation of PKC activity and diabetes induced decrease of both Na + K + ATPase and Ca 2+ ATPase activities. D ? tocopherol achieved a complete prevention of augmented pericyte and endothelial cell profile areas and basement membrane thickening in the superficial and deep capillaries bed of diabetic retina but had no effect on blood glucose and HbA 1c . Conclusion Diabetes induced histopathological abnormalities are mostly mediated by PKC. D ? tocopherol reduces the ultrastructural lesions in retinal capillary bed induced by hyperglycemia.

BACKGROUND:Human umbilical cord blood-derived mesenchymal stem cels can be induced through the co-culture to differentiate into other cels, but how to get more seed cels for tissue engineering is one of the most difficult problems. OBJECTIVE: To investigate the role of the different concentrations of thyroxine in chondrogenic differentiation of human umbilical cord blood-derived mesenchymal stem cels by co-culture with rabbit chondrocytes. METHODS:Human umbilical cord blood-derived mesenchymal stem cels were co-cultured with rabbit chondrocytes at 2:1, and stimulated by medium containing different concentrations of thyroxine (0, 0.01, 0.1 and 1, 10 μmol/L). Co-cultured cels with no thyroxine served as control group. After 14 days of co-culture, the cel RNA and protein were extracted, mRNA expressions of aggrecan and colagen type II were detected by real-time PCR, and protein expression of aggrecan and colagen type II were detected by western blot assay. RESULTS AND CONCLUSION:After intervention with 0.01, 0.1, 1, 10 μmol/L thyroxine, the mRNA and protein expressions of aggrecan and colagen type II were enhanced with the increase of thyroxine concentration, which were significantly different from those in the control group (P < 0.05). Experimental findings indicate that high levels of thyroxine can enhance the chondrogenic ability of human umbilical cord blood-derived mesenchymal stem cels co-cultured with rabbit chondrocytes.

Rare sugars were defined as monosaccharides and their derivatives that rarely exist in nature. They played an important role in food, health, medicine and etc A strategy for bioproduction of rare sugars, namely Izumoring, was described. By the Izumoring method, all monosaccharides and polyols could be linked, using enzymatic reaction with D-tagatose 3-epimerase, aldose isomerases and polyol dehydrogenases. Izumoring for hexoses, pentoses and tetroses were designed respectively. According to this strategy, the bioproduction routes of various rare sugars, using microbial and enzymatic reactions, could be obtained. In addition, the future research tendency of biotransformation of rare sugars was put forward.

Thermostable L-arabinose isomerase (L-AI) is the most potential enzyme for the biological production of D-tagatose from D-galactose, a novel functional factor. Gene araA encoding the L-arabinose isomerase from Bacillus stearothermophilis IAM 11001 was cloned and expressed in Escherichia coli. The araA gene of 1491 bp has 95% identity with L-AI from Thermus sp. IM6501. The GenBank accession number for the nucleotide sequence of this araA gene determined in this work is EU394214.The bacterium was induced by IPTG and analyzed by SDS-PAGE, approximately 59 kDa exogenous protein was observed on the SDS-PAGE. The recombinant L-AI was purified to electrophoretical homogeneity with affinity chromatography, and the activity of recombinant L-AI was also studied. The bioconversion rate of D-galactose to D-tagatose reached 39.4% after 24h whole cell reaction.

L-arabinose isomerase (L-AI) can isomerize L-arabinose and D-galactose into L-ribulose and D-tagatose, respectively, which is currently the most effective biological catalyst for D-tagatose production. The crystal structure of L-AI has been solved recently and its gene has been cloned, sequenced and overex- pressed. L-AI improved by protein engineering will be the dominant enzyme for industrial production of D-tagatose. This paper reviewed researches on protein structure and function, properties and application in D-tagatose production of L-AI, and the long-term potential development of L-AI was prospected.

Objective To prepare the acellular scaffold of spinal cord and analyze its component.Methods The acellular scaffold was prepared with the freeze thawing and chemical extraction,its structure was observed by HE and SEM,its component was analyzed by immunohistochemistry.Results The cells,myelin sheath and axon of nerve fibers in the rat spinal cord were eliminated,but three-dimensional supports of extracellular matrix were reserved.The analytical results showed the component of the acellular spinal cord contain laminin,fibronectin and type Ⅳ collagen—the necessary components to facilitate and induce the regeneration of the injured nerves and enhance the adhesion and proliferation of cells.Conclusion The acellular spinal cord has three dimensional structure and contains several proteins related to the regeneration of the injured nerves and promotion of the survival and proliferation of cells.

Objective To evaluate the relationship between aberrant crypt foci(ACF) and colon cancer by observing the sequential development of ACF in cancer models of rats. Methods The colon cancer models in 60 Wistar rats were established by subcutaneously injection of dimethylhydrasine (DMH) once a week for 18 weeks. The rats were sacrificed and the colon tissues stained by methylene blue were observed with a stereomicroscope. Results There were two types of ACF, named cACF and dACF. The microscopic findings in dACF were similar with that in early colon cancer, while those in cACF were not. The expression of β-catenin in cACF and dACF were 4. 84% and 100% (P =0. 000) , respectively, and the expression of MMP-7 were 7. 87% and 81.82% (P =0. 000), respectively. There was no significant difference in expression of β-catenin and MMP-7 between dACF and colon cancer ( P ＞ 0. 05 ). Conclusion The microscopic and molecular changes in dACF is similar with that in colon cancer, and dACF may progress to cancer through Wnt pathway.

Objective To investigate the effects of transplantation of oligodendrocyte precursor cells(OPCs) on the recovery of neural function in rats with spinal cord injury.Methods The spinal cord injury(T10) rat model was established by Allen's method of weight-drop injury.Ninety six SD rats were randomly divided into 4 groups(24 each): transplantation group,control group,injury-only group and sham-operation group.Seven days after spinal cord injury,the rats of transplantation group received OPCs transplantation,of control group were injected with equivalent saline,and of injury-only group were untreated.The effects of OPCs transplantation on neural functional recovery in spinal cord injured rats were measured by the behavioral test and assessments of motor evoked potentials(MEP) and somatosensory evoked potentials(SEP).Results Immediately after spinal cord injuries,the neural function of spinal cord of rats was markedly impaired.The results of behavioral test,MEP and SEP in injured rats were much worse than those in sham-operation group.Although the neural function in spinal cord injured rats improved in different degrees with the time,the results of behavioral test,MEP and SEP showed it was significantly better in transplantation group than that in control group.Conclusion The transplantation of OPCs may enhance the recovery of neural function of rats with spinal cord injuries.

Objective To analyze slowly the digestibility and postprandial glycemic response after consum of different cereal starch. Method Starch was quantified into different nutritional fractions using the in vitro Englyst test. Ten healthy subjects consumed 7 kinds of carbohydrate foods with 50 g normal maize starch, waxy maize starch, wheat starch, sticky rice starch, rice starch, potato starch or glucose. Blood samples from postprandial zero to 120 min after consumption of test materials were collected for measurement of glucose, glycemic index and extended glycemic index. Results Native cereal starch was ideal slowly digestible starch (SDS) and the proportion of SDS was about 50% based on Englyst test. The GI value of cereal starch was more than 90% and belonged to high glycemic index foods, but EGI was positive, regarding glucose powder as 100%. Conclusion Cereal starch with slow digestibility and similar glycemic response was a better carbohydrate material to provide a slow and prolonged release of blood glucose and maintenance of glucose homeostasis, which was potentially beneficial to health.