ABSTRACT
Objective@#To explore the effect of the umbilical cord mesenchymal stem cells(UC-MSCs) on the pulmonary fibrosis in silicosis rats.@*Methods@#SPF male Sprague Dawley rats were randomly divided into control group, silica model group and UC-MSCs treatment group with 12 rats each group. SiO2 intra-tracheal injection(0.5 ml of 50 mg/ml/rat) were applied to silica model group and UC-MSCs treatment groups. After that UC-MSCs treatment group received 1 ml UC-MSCs suspension (3×106 cells/ml) by tail vein injection on the 29th, 36th, 43th and 50th day after exposure to the first silica suspension. On the 60th and 75th day after exposure to silica suspension, all animals were examed for pulmonary CT. Then the rats were euthanized on 75th day after the first exposure to silica.Lung's histopathological examination of the rats from all the groups were carried out. The content of hydroxyproline in lungs, TGF-β1 and IL-6 in serum were examined.@*Results@#The lung's histopathological examination showed no obvious inflammatory cell and no fibrosis in the lung tissue of the control group, there were a lot of inflammatory cell aggregation and collagen fiber deposition in silica model group, while in the UC-MSCs intervention group and treatment group, there were less inflammatory cells and collagen fiber. The rats from silica model groups had higher HYP, TGF-β1 and IL-6 than the rats from UC-MSCs treatment group and control group. Lung fields of rats in the control group were clear and no obvious high-density shadow. Different-sized granular high-density shadows or reticular fibrous shadows were found diffusely distributed in the lungs of the rats in silica model group. Lung field of rats in UC-MSCs intervention group and treatment group were less high density shadows, and more clear.@*Conclusion@#UC-MSCs can alleviate the pulmonary fibrosis in silica model rats through regulating the secretion of some fibrosis related cytokines.
ABSTRACT
Carotenoids are a class of terpenes of commercial interest and exert important biological functions. Engineering morphological and biosynthetic aspects of Escherichia coli cell membrane could improve its storage capacity for β-carotene. However, how the synthesis of phosphatidylethanolamine, the major component of the cell membrane, was not discussed in detail. In this work, the synthesis of phosphatidylethanolamine was divided into three modules to discuss their synergetic effect, by expressing in different combinations. Overexpressing the upstream module 1 in CAR016 caused a 30.5% increase of β-carotene specific production (from 10.1 mg/g to 13.7 mg/g DCW); combined overexpressing module 1 and module 2 in CAR016 led to a 122% increase of β-carotene specific production (from 10.5 mg/g to 22.3 mg/g DCW). The optimal expression combination of the phosphatidylethanolamine synthetic pathway was obtained, which further increased the content of the cell membrane for β-carotene storage, and improved its production. The membrane engineering strategy opens up a new direction for engineering microbial producers for a large spectrum of hydrophobic molecules.
ABSTRACT
Objective To determine the real time radiation dose rate displayed on DSA equipment in interventional management for patients with coronary heart disease in order to provide medical staff with useful basis to reasonably control the radiation dose. Methods A total of 30 patients with coronary heart disease, who received interventional treatment at authors’ hospital in September 2014 with a GE DSA unit, were randomly selected. Intraoperative radiation dose rates when fluoroscopy was converted to movies , which were displayed on DSA at respective sequence, were determined, and the results were analyzed and compared. Results The fluoroscopy radiation dose rate ranged from 18.5 to 212.0 mGy/min, the mean value was (114.7±42.1) mGy/min;while the radiation dose rate of movies varied from 216 to 1 691 mGy/min, with a mean value of(970.1±298.4) mGy/min. The overall mean fluoroscopy-to-movies radiation dose ratio was 1 ∶8.5. The larger the digital flat panel detector area was , the bigger the mean radiation dose rate would be and the more obvious increase in the mean radiation dose rate of movies than that of the fluoroscopy would be observed; the mean radiation dose rate of fluoroscopy was lower than that of movies , and the difference was significantly. Conclusion During the performance of coronary intervention , the medical staff should make reasonable choice of the equipment and closely observe the dynamic real-time display of the radiation dose rate, promptly adjust the inspection mode and the controllable parameters when it is needed , make immediate evaluation of dose level that might cause radiation injury to the patient , and reasonably control the radiation dose to reduce the effects of ionizing radiation on human health.