Objective:To observe the effects of preventative moxibustion on analgesia,substance P(SP),prostaglandin(PG)F2α and PGE2 in rats with dysmenorrhea due to cold-dampness stagnation,and to explore the analgesic mechanism. Methods:Sixty-four female Wistar non-pregnant rats were randomly divided into a blank group,a model group,a Western medicine group,and a preventative moxibustion group,with 16 rats in each group.Eight qualified diestrus rats were selected from each group.Except for the blank group,the other three groups established models of dysmenorrhea due to cold-dampness stagnation using an ice water bath combined with estradiol benzoate and oxytocin.On the 8th day after modeling,the preventative moxibustion group was treated with gentle moxibustion at Shenque(CV8)and Guanyuan(CV4),and the Western medicine group was given ibuprofen solution for 4 consecutive days.On the 11th day,the intervention groups(i.e.the Western medicine group and the preventative moxibustion group)were treated once again after being injected with oxytocin.The writhing score and the pain threshold of rats were determined;the serum levels of brain-derived neurotrophic factor(BDNF),SP,PGF2α,and PGE2 were measured;the mRNA and protein expression levels of BDNF and its receptor tropomyosin receptor kinase B(TrkB)in the spinal dorsal horn and hypothalamus were detected. Results:Compared with the blank group,the writhing score increased(P<0.01),the pain threshold decreased(P<0.01),the serum levels of BDNF,SP,and PGF2α increased(P<0.01),while the PGE2 decreased(P<0.01);the protein and mRNA expression levels of BDNF and TrkB in the spinal dorsal horn and hypothalamus increased(P<0.01)in the model group.Compared with the model group,the writhing score decreased,the pain threshold increased,the serum BDNF,SP,and PGF2α levels decreased significantly,the serum PGE2 level increased,and the protein and mRNA expression levels of BDNF and TrkB in the spinal dorsal horn and hypothalamus decreased significantly in the preventative moxibustion group and the Western medicine group,while the inter-group differences were significant(P<0.01).Compared with the Western medicine group,the writhing score decreased,the pain threshold increased,the serum BDNF,SP,and PGF2α,levels decreased,the serum PGE2 level increased,and the protein and mRNA expression levels of BDNF and TrkB in the spinal dorsal horn and hypothalamus in the preventative moxibustion group decreased significantly,while the inter-group differences were significant(P<0.05 or P<0.01). Conclusion:Preventative moxibustion at Shenque(CV8)and Guanyuan(CV4)can improve the pain sensitization state of rats with dysmenorrhea due to cold-dampness stagnation,down-regulate the mRNA and protein expression levels of BDNF and TrkB in the spinal dorsal horn and hypothalamus;regulation of the serum SP,PGF2α,and PGE2 levels may be part of the mechanism.

Objective To establish a finite element model of cell perfusion culture, and study the effect of different perfusion speeds on the movement of suspended cells. Methods The two-dimensional (2D) model of cell and microchannels was established using COMSOL Multiphysics and meshed. Three groups were established according to the perfusion speed, namely, u0=0.196 mm/s, u1=0.117 mm/s, u2=0.04 mm/s. The fluid-structure interaction module was used for calculation. Results The flow field distribution in the microchannel was relatively uniform. During the equal period of time, the ratio of cell suspension perfusion speed was u0∶u1∶u2=5∶3∶1, and the ratio of cell displacement in the microchannel was D0∶D1∶D2=4.1∶ 2.9∶1. When the speed was proportional, the displacement of cells also roughly followed the corresponding proportional change. With the increase of perfusion speed, stress concentration in cells during movement would occur. The stress and fluid shear force (FSS) of cells during movement were within the safe value range, and cell destruction would not occur. Conclusions The suspended cells can enter into the microchannel without injury at a certain perfusion speed. Perfusion techniques can be used in cell implantation of in vitro tissue engineering products.

Objective To observe the analgesic effects of mild moxibustion on primary dysmenorrhea(PD)rats with cold and dampness stagnation syndrome and its effect on BDNF/TrkB signaling pathway in hypothalamus;To explore its mechanism for the treatment of PD.Methods A total of 32 Wistar non-pregnant female rats were randomly divided into blank group,model group,Western medicine group and mild moxibustion group,with 8 rats in each group.Except for the blank group,the other groups received estradiol benzoate intraperitoneal injection combined with ice bath treatment + oxytocin intraperitoneal injection to establish PD with cold and dampness stagnation syndrome model.The mild moxibustion group received treatment at"Shenque"and"Guanyuan"from the eighth day of modeling for 10 min,and the Western medicine group was given ibuprofen solution intragastically for 4 days.The latency period of rats twisting was observed and the twisting score was calculated,Western blot and PCR were used to detect the expressions of c-fos,BDNF,TrkB protein and mRNA in hypothalamic tissue.Results Compared with the blank group,the model group showed a shortened latency period and an increased twisting score(P<0.01),the expressions of c-fos,BDNF,TrkB protein and mRNA in hypothalamic tissue increased(P<0.01,P<0.05).Compared with the model group,the mild moxibustion group had a longer latency period and lower twisting score(P<0.01),while the expressions of c-fos,BDNF,TrkB protein and mRNA in hypothalamic tissue increased(P<0.01,P<0.05).Conclusion Mild moxibustion may effectively improve the pain state of PD rats with cold and dampness stagnation syndrome.This mechanism may be related to downregulating c-fos expression,inhibiting BDNF/TrkB signaling pathway activation,thereby inhibiting pain signal transmission,regulating pain occurrence and maintenance.

At present, acellular matrix is an effective replacement material for the treatment of skin damage, but there are few systematic evaluation studies on its performance. The experimental group of this study used two decellularization methods to prepare the matrix: one was the acellular matrix which sterilized with peracetic acid first (0.2% PAA/4% ethanol solution) and then treated with hypertonic saline (group A), the other was 0.05% trypsin/EDTA decellularization after γ irradiation (group B); and the control group was soaked in PBS (Group C). Then physical properties and chemical composition of the three groups were detected. Hematoxylin eosin (HE) staining showed that the acellular effect of group B was good. The porosity of group A and B were both above 84.9%. In group A, the compressive modulus of elasticity was (9.94 ± 3.81) MPa, and the compressive modulus of elasticity was (12.59 ± 5.50) MPa in group B. There was no significant difference between group A or B and group C. The total content of collagen in acellular matrix of group A and B was significantly lower than that of group C (1. 662 ± 0.229) mg/g, but there was no significant difference in the ratio of collagen Ⅰ/Ⅲ between group B and group C. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed that there was no significant difference in microstructure. Qualitative detection of fibronectin and elastin in each group was basically consistent with that in group C. Therefore, acellular matrix of group B had better performance as scaffold material. The experimental results show that the acellular matrix prepared by γ-ray sterilization and decellularization of 0.05% Trypsin enzyme/EDTA could be used for the construction of tissue-engineered skin. It could also provide reference for the preparation and mounting of heterogeneous dermal acellular matrix. It was also could be used for electrostatic spinning or three-dimensional printed tissue engineered skin scaffold which could provide physical and chemical parameters for it.
Acellular Dermis ; Cells, Cultured ; Extracellular Matrix ; Porosity ; Tissue Engineering ; Tissue Scaffolds

Objective To explore the mechanism of the treatment of primary dysmenorrhea(PD)by mild moxibustion on"Shenque"and"Guanyuan"acupoints based on the regulation of cAMP-PKA signaling pathway on TRPV1.Methods Totally 32 female non-pregnant Wistar rats were randomly divided into blank group,model group,mild moxibustion group and capsazepine group,with 8 rats in each group.Except for the blank group,the other groups all used estradiol benzoate intraperitoneal injection combined with ice water bath to establish a PD cold-dampness stagnation syndrome rat model.Intervention began on the first day of modeling,the mild moxibustion group selects"Shenque"and"Guanyuan"for mild moxibustion,20 min per time,the capsazepine group was injected capsazepine 2 mg/kg,once a day for 10 consecutive days.ELISA was used to detect uterine PGF2α and cAMP content,immunofluorescence staining was used to detect TRPV1 expression in uterine tissue,Western blot was used to detect PKA,p-PKA and TRPV1 protein expression.Results Compared with the blank group,the latency period of body twisting in the model group rats decreased,and the body twisting score increased(P<0.01);the contents of PGF2α and cAMP in uterine tissue increased(P<0.01),and the expressions of TRPV1 and p-PKA proteins increased(P<0.01).Compared with the model group,the mild moxibustion group and capsazepine group showed an increase in the latency period of body twisting and a decrease in the body twisting score(P<0.01);the content of PGF2α and cAMP in uterine tissue decreased(P<0.01),and the expressions of TRPV1 and p-PKA proteins decreased(P<0.05,P<0.01).Compared with the mild moxibustion group,the capsazepine group showed an increase in the latency period of body twisting and a decrease in the body twisting score(P<0.01);the contents of PGF2α and cAMP in uterine tissue decreased(P<0.05,P<0.01),and the expressions of TRPV1 protein decreased(P<0.05).Conclusion Mild moxibustion at"Shenque"and"Guanyuan"acupoints has obvious analgesic effect on PD rats,and its mechanism may be related to the regulation of uterine cAMP-PKA signaling pathway mediated TRPV1 protein expression.