ABSTRACT
Synthetic biology is an emerging interdisciplinary research field. By designing and constructing new or re-designing the existing natural systems, it confers them novel functions, which do not exist in nature. Owing to the predictability and controllability, synthetic biology attracts more and more interest from biologists, physicists, and engineers. Synthetic biology approaches not only can be widely used for biotechnological applications but also can be used to study complex biological systems to address fundamental questions. Here, we reviewed the recent studies following the concept of "build-to-understand", particularly, the studies to understand intracellular network structure, cell physiology, the behavior of multicellular populations, and ecosystems.
ABSTRACT
BACKGROUND:Chinese herb Cape Jasmine Fruit can activate the chondrocytes and geniposide is an important component in this herb. OBJECTIVE:To investigate the effect of geniposide on col agen II synthesis in rat chondrocytes cultured in vitro. METHODS:Rat chondrocytes were separated and cultured in vitro. The chondrocytes were then interfered with 25, 50 and 100 mmol/L geniposide. Normal control group was also set. Col agen II mRNA and protein expression was detected with semi-quantitative RT-PCR and western blot analysis, respectively. RESULTS AND CONCLUSION:RT-PCR and western blot analysis results showed that, geniposide at 25, 50 and 100 mmol/L increased the col agen II mRNA and protein expression (P<0.01). Geniposide can promote the synthesis of col agen II in rat chondrocytes cultured in vitro.
ABSTRACT
Objective To investigate the age-associated changes of ultrastructure,mRNA and protein expressions of H+-K+-ATPase in elderly gastric parietal cell. Methods Fifty patients with relative normal stomach without gastroduodenal diseases were enrolled,including younger group (aged 20-59 years,n=19) and elderly group (aged≥60 years,n=31).Furthermore,the elderly group was divided into 3 subgroups:60-69 years old (n =11 ),70-79 years old (n=10 ),above 80 years old (n =10).The ultrastructure of gastric parietal cell was observed under electron microscope.The expression of H+-K+-ATPase α subunit mRNA and H+-K+-ATPase β subunit protein were assessed by quantitative real-time PCR and Western-blot,respectively.The ageing-associated changes of all these data were respectively compared. Results No significant difference was showed in the morphology of gastric parietal cell and acid-secretion-associated organelles among all the groups.The average ratio Am to Ac (Am means the area of mitochondria,Ac means the area of cytoplasm) of gastric parietal cell and the average At to Ac ratio (At means the area of secretory canaliculi and tubulovesicular system )between younger group and elderly group had no significant difference[(48.4±7.5) ％ vs.(50.6±7.6) ％,t=-0.775,P=0.444; (13.8±4.1) ％ vs.(12.2±4.7) ％,t=0.984,P=0.332].Meanwhile,there were no distinctions in the expression of H+-K+ -ATPase α subunit mRNA and H+-K+-ATPase protein among all elderly subgroups(F=1.522,2.32,P=0.24,0.114).However,the mRNA expression of H+-K+-ATPase a subunit was higher in the elderly group than in the younger group(t=-3.682,P=0.001).Furthermore,the expression of H+ -K+ -ATPase protein in the elderly group was increased as compared with younger group(t=-3.389,P=0.004). Conclusions Acidsecretion-associated organelles of human gastric parietal cell have no degeneration and the expression of H + -K+-ATPase is in trend of increase with aging,indicating that healthy elderly people have the basis of ultrastructure and molecular biology to maintain well function of acid secretion.
ABSTRACT
Objective To investigate the morphological changes, apoptosis and brain-derived neurotrophic factor mRNA(BDNF mRNA)expression in rat conus medullaris induced by cauda equine compression, and to discuss the possible mechanisms. Methods Ninety male SD rats were divided into 3 groups: normal control, sham operation,and cauda equine compressed. The animals were sacrificed and took samples in 30 min, 2 hours,4 hours,8 hours,1 day,3 days,1 week,2 weeks,3 weeks after cauda equine compression model were created. The morphological study concerned with cauda equina and conus medullaris was done under light microscope and transmission electron microscope. TUNEL staining and in situ hybridization staining were used to investigate apoptosis and BDNF mRNA expression changes. The positive cells in 1mm2 were calculated,and the data were disposed through one way analysis of variance. Results Histological observation showed notable alteration of cauda equina and neurons in conus medullaris. The positive cells of TUNEL and BDNF mRNA in situ hybridization staining increased in 8 hours and 4 hours after cauda equina compressed,and both reached the climax in 3days after cauda equina compressed. At the time 3weeks after cauda equine compressed, the positive cells were still much higher than that of the control groups. Conclusion The compression of cauda equina will result in neurons morphological changes and apoptosis in medullary cone,and cause central neuron un-reversible injury. It might be one of the reasons why the prognosis is poor in cauda equina syndrome. Neurons and glial cells may produce BDNF by themselves to survival from cauda equina compression.