[Treatment Efficiency and Microbial Community Diversity in a Magnetic Field Enhanced Sequencing Batch Reactor (SBR)].

The application of SBR reactors is becoming more common and in order to further improve the efficiency of their treatment it has been proposed to add a magnetic field to SBR systems. The effects of different magnetic fields on the degradation efficiency of conventional pollutants in an SBR was studied. MiSeq high-throughput sequencing techniques were used to analyze the diversity of microbial communities in activated sludge under magnetic field conditions. These results show that the addition of a magnetic field improves the performance of a SBR system to an extent and magnetic induction effects are most obvious at 7×10-2 T. This is identified through a significant effect on the removal efficiency of total nitrogen and an increase in the denitrification rate from 65.69% to 85.98%. It also significantly improves the activity of sludge dehydrogenase and has a positive effect on the removal of various pollutants. The diversity of microbial communities in activated sludge under different magnetic field intensities shows a greater microbial abundance and diversity in the active sludge. The bacterial domain in the experimental SBR includes 14 phyla, which are mainly Proteobacteria (25.3%-61.5%), Bacteroidetes (18.6%-46.2%), Actonobacteria (5.3%-47.2%), and Acidobacteria (0.4%-4.0%). Important denitrification bacteria such as Rhodoblastus, Paracoccus of α-Proteobacteria, Alicycliphilus, Comamonas, Xenophilus, Acidovorax, Dechloromonas, Thauera of ß-Proteobacteria, Desulfovibrio of δ-Proteobacteria and Planctomycetes, etc. at a moderate magnetic induction of 7×10-2 T have a high abundance and there is an internal relationship between this and an increase in denitrification efficiency. Polyphosphate-accumulating organisms (PAOs) such as Acinetobacter, Pseudomonas, Propionicimonas, etc., are present at higher levels under these conditions and follow the same trends as for the phosphorus removal rates. There is a correlation between bacterial community structure changes and sewage treatment efficiency in activated sludge. Applied magnetic fields have a positive effect on sewage treatment by changing the microbial community structure.

Establishment of a rabbit model of small diameter vascular graft replacement / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish an rabbit model that mimics the hemodynamics of the bypass graft after coronary artery bypass surgery.</p><p><b>METHODS</b>Sixteen New Zealand rabbits were randomly divided into two groups for abdominal aortic artery replacement using a 3-cm-long ePTFE graft with an inner diameter 4 mm through an incision at 1/3 from the middle to the lower part of the abdomen (group A) or in the lower abdomen (group B). The general conditions of the rabbits, operative time, number of collateral vessels that needed to be ligated, rate of massive intraoperative bleeding, fluctuation of vascular anastomosis after surgery, patency rate of the graft on day 7 after the operation were compared between the two groups.</p><p><b>RESULTS</b>The two groups of rabbits had similar body weight, diameter of the abdominal aortic artery, intraoperative bleeding rate and occlusion rate of the vascular graft at 7 days after the procedure. The operative time was longer in group A, but the difference was not statistically significant. In group A, the number of the vascular branches that needed to be ligated was smaller and the rate normal femoral artery pulsation was higher than those in group B.</p><p><b>CONCLUSION</b>It is feasible to establish models of small diameter vascular graft replacement in rabbits, and the patency rate of the graft can be monitored by observation of the general condition and ultrasound examination of the rabbits.</p>

Relationship between early spontaneous cardioversion of atrial fibrillation and thyroid hormone metabolism after mitral replacement in patients with rheumatic heart disease / 南方医科大学学报

<p><b>OBJECTIVE</b>To analyze the relationship between early spontaneous cardioversion of atrial fibrillation (AF) and thyroid hormone metabolism after mitral replacement in patients with rheumatic heart disease, and explore the treatment strategy of early spontaneous cardioversion after mitral valve replacement.</p><p><b>METHODS</b>According to the occurrence of cardioversion, 138 patients with mitral valve replacement were divided into conversion group and non-conversion group, and based on the duration of sinus rhythm, the patients in conversion group were divided into < 3 days group and > 3 days group. Triiodothyronine (T3) was detected by radioimmunoassay in all the patients.</p><p><b>RESULTS</b>T3 metabolism decreased significantly after the operation in all the patients. Early spontaneous cardioversion of AF occurred 2 h after the operation in 52 cases (37.7%), and 28 (20.3%) of the cases had a duration of sinus rhythm longer than 3 days. T3 was significantly decreased in conversion group and non-conversion group by 44.5% and 58.7% at 2 h, by 40.0% and 52.4% at 24 h and by 28.6% and 37.7% at 72 h after the operation, respectively. The levels of T3 in conversion group was significantly higher than the levels in non-conversion group, and showed no significant variation with the duration of sinus rhythm.</p><p><b>CONCLUSION</b>Enhancement of T3 levels after mitral valve replacement may increase the probability of early spontaneous cardioversion of AF, but can not affect the duration of sinus rhythm. This finding supports the supplementation of T3 perioperatively in patients undergoing cardiac surgeries.</p>

Hemocompatibility evaluation in vitro of small-caliber expanded polytetrafluoroethylene vessel with silk fibroin coating sulfonated by low temperature plasma / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the hemocompatibility of a small-caliber expanded polytetrafluoroethylene vessel with silk fibroin coating sulfonated by low temperature plasma treatment.</p><p><b>METHODS</b>The composite blood vessel was prepared by first coating the small-caliber expanded polytetrafluoroethylene vessel with silk fibroin followed by sulfonation by low temperature plasma treatment. After hemolysis test in vitro, dynamic coagulation time test, blood platelet adhesion test, and recalcification time test were performed to evaluate the hemocompatibility of the composite blood vessel.</p><p><b>RESULTS</b>Scanning electronic microscopy revealed obvious platelets adhesion on the conventional artificial (control) vessel, which seldom occurred on the composite vessel. The curve of absorbance-clotting time of the composite vessel declined more slowly than that of the control vessel. The recalcification time of the composite blood vessel averaged 603 s, significantly longer than that of the control vessel (480 s, P = 0.000).</p><p><b>CONCLUSION</b>The composite blood vessel has good antithrombotic activity and hemocompatibility as a promising vascular prosthesis.</p>

Expression of special AT-rich sequence-binding protein mRNA and its clinicopathological significance in non-small cell lung cancer / 南方医科大学学报

<p><b>OBJECTIVE</b>To detect the expression of AT-rich sequence-binding protein (SATB1) mRNA in non-small cell lung cancer (NSCLC) and explore the role of SATB1 in the development of NSCLC.</p><p><b>METHODS</b>The total RNA was extracted from NSCLC tissues and normal lung tissues and reverse transcribed into cDNA. Real-time fluorescence quantitative RT-PCR was performed for detecting the expression of SATB1 mRNA these tissues.</p><p><b>RESULTS</b>The expression of SATB1 mRNA was 13-fold higher in NSCLC tissues than in normal lung tissues (P<0.001), and in metastatic and nonmetastatic NSCLC, the expression was 23.63 and 5.57 folds that in normal lung tissues, respectively.</p><p><b>CONCLUSION</b>SATB1 mRNA expression might be associated with the development and lymph node metastasis of NSCLC and may potentially used as an indicator for predicting the prognosis of NSCLC.</p>