ABSTRACT
Objective:To investigate the effects of Da Jianzhongtang on substance P （SP）， mast cells （MC）， Toll like receptor 2 （TLR2）， TLR4 on MC model and nuclear transcription factor （NF）-<italic>κ</italic>B p65 in visceral pain rats with irritable bowel syndrome （IBS）， and explore its mechanism of action on IBS visceral pain. Method:Forty-eight 3-day-old SD rats were randomly divided into 6 groups： the control group （control）， irritable bowel syndrome group （IBS）， ketotifen group （Ketotifen，0.18 mg·kg<sup>-1</sup>）， Da Jianzhongtang low， medium and high dose groups （DJZT-L， DJZT-M， DJZT-H，2.16，1.08，0.54 g·kg<sup>-1</sup>）， with 8 rats in each group. Intragastric administration lasted for 2 weeks. Maternal separation method was used to establish the IBS visceral pain model in rats. The visceral sensitivity of rats was evaluated at 60， 40 and 20 mmHg （1 mmHg≈0.133 kPa） with Abdominal wall withdrawal response （AWR） scale. SP and NF-<italic>κ</italic>B p65 protein expression levels in colon tissue were detected with Western blotting technique. TLR2 and TLR4 proteins on mast cell membrane were detected by immunofluorescence staining. The degranulation rate of mast cells in colon tissue was detected by toluidine blue staining. Result:Compared with normal rats， AWR scores of model rats significantly increased at 60， 40， and 20 mmHg pressure （<italic>P</italic><0.05，<italic>P</italic><0.01）， the degranulation rate of mast cells in colon tissue and SP protein expression in colon tissue significantly increased （<italic>P</italic><0.01）， TLR2， TLR4， and nuclear NF-<italic>κ</italic>B p65 expression on mast cell membrane significantly increased （<italic>P</italic><0.01）. Compared with model rats， the AWR scores of DJZT-H group （pressure of 40， 20 mmHg） and DJZT-M group （pressure of 60， 40， 20 mmHg） significantly decreased. Meanwhile， the degranulation rate of colon mast cells， and the SP， TLR2， TLR4， and NF-<italic>κ</italic>B p65 expression also significantly decreased （<italic>P</italic><0.05，<italic>P</italic><0.01）. Conclusion:Da Jianzhongtang can affect mast cell activity and finally decrease visceral pain of IBS rats by down-regulating SP in colon tissue.
ABSTRACT
<p><b>BACKGROUND</b>Human group O red blood cells have great benefit in specialized transfusion areas such as armed conflict and natural calamity. The group B antigen differs structurally from group O antigen only by the addition of one terminal alpha-linked galactose residue. In this study we aimed to remove the terminal galactose from group B red blood cell to get group O red blood cell.</p><p><b>METHODS</b>alpha-galactosidase cDNA was cloned by RT-PCR from Catimor coffee beans grown on Hainan Island of China. The vector for alpha-galactosidase cDNA expression was constructed and transferred into Pichia pastoris cells by electroporation. The transgenic cells were cloned by fermentation and the recombinant alpha-galactosidase was purified by ion exchange chromatography. After studying the biochemical characters of alpha-galactosidase, we have used it in converting human erythrocytes from group B to group O.</p><p><b>RESULTS</b>The purity of recombinant alpha-galactosidase was higher than 96%, which was thought to be suitable for the use of blood conversion. Enzymatically converted human group O red blood cells (ECHORBC) exhibited membrane integrity, metabolic integrity, normal cell deformation and morphology. There were no coagulation between ECHORBC and any group of human blood. The ECHORBC will keep normal structure and function for a period of 21 days at 4 degrees C in monoammoniumphosphate nutrient solution. Experiments with Rhesus monkeys and gibbons showed that transfusion of enzymatically converted erythrocytes was safe.</p><p><b>CONCLUSION</b>ECHORBC can be easily obtained from group B red blood cell by alpha-galactosidase digestion. This study suggests that ECHORBC could be transfused to patients safely and efficiently.</p>