OBJECTIVETo observe the analgesic effect of electroacupuncture (EA) on collagen-induced arthritis (CIA) rats and its regulating effect on inflammation reaction and the endogenous opioid system of synovial tissues. Methods A total of 30 healthy male Wistar rats were randomly divided into a control group, a model group and an EA group, 10 rats in each one. The chronic pain model of CIA rats was made by cattle type-II collagen in the model group and EA group. Rats in the EA group were treated with EA at "Zusanli" (ST 36) and "Kunlun" (BL 60) for 30 min from 16th day after model establishment, once a day for consecutive 10 days. Rats in the control group did not receive any treatment. Rats in the model group were treated with fixation as the EA group. Threshold of pain, arthritis index, paw swelling were measured before model establishment and 16 d, 20 d, 23 d and 25 d after model establishment. The levels of beta-endorphin (β-END), met-enkephalin (met-ENK), dynorphin A (Dyn A) were measured by radioimmunoassay; the mRNA expressions of mu opioid receptor (MOR), kappa opioid receptor (KOR) and delta opioid receptor (DOR) in synovial tissues of CIA rats were detected by I quantitative polymerase chain reaction (qPCR).

RESULTSCompared with the control group, threshold of pain was reduced (all P<0. 01), arthritis index was increased (all P<0. 01) and paw swelling was increased (all P<0. 01) in the model group on the 16th day, 20th day, 23rd day, 25th day after model establishment. Compared with the model group, the threshold of pain was increased in the EA group (all P<0. 01), arthritis index and paw swelling were reduced (all P<0. 01) on the 23rd day and 25th day after model establishment. Compared with the control group, the level of Dyn A in synovial tissues of CIA rats was increased in the model group (P<0. 01); the mRNA expressions of MOR, KOR and DOR were down-regulated lower than 0. 5 fold of normal level. Compared with the model group, the level of β-END in synovial tissues of the knee joint was increased in the EA group (P<0. 05), and the mRNA expressions of MOR, KOR and DOR in synovial tissues of CIA rats were up-regulated more than 2 folds of normal level.

CONCLUSIONThe intervention of EA on chronic pain of CIA rats is superior, which is likely to be related with effects of EA on anti-inflammation and up-regulation of synovial tissue β-END and MOR, KOR, DOR.

Acupuncture Analgesia ; Acupuncture Points ; Analgesics, Opioid ; immunology ; Animals ; Arthritis, Rheumatoid ; immunology ; therapy ; Cattle ; Chronic Pain ; immunology ; therapy ; Dynorphins ; genetics ; immunology ; Electroacupuncture ; Enkephalin, Methionine ; genetics ; immunology ; Humans ; Male ; Rats ; Rats, Wistar ; Receptors, Opioid, mu ; genetics ; immunology ; Synovial Fluid ; immunology ; beta-Endorphin ; genetics ; immunology

Objective To investigate the change of mu opioid receptor ( MOR) in dorsal root ganglion ( DRG) in rat chronic inflammatory pain model and the effect of MOR agonist and antagonis tintraplantarly ( i.pl.) injected on pain threshold, so as to determine the role of peripheral MOR in chron in inflammatory pain .Methods Chronicin flammatory pain model was established by i .pl.injection of CFA in rats.The expression of MOR in DRG was detected by immunohistochemistry .Pain threshold before and after i .pl.injection of MOR agonist and antagonist was measured by radiant heat method .Results Rats suffered from an intraplantar injection of CFA developed chronic inflammatory pain , and the painthreshold still reduced on 18 day after CFA injection compared to that in the normal group . Immunohistochemistry staining revealed that compared with the normal group , the expression of MOR in DRG of CFA rats was increased ( P<0.01 ) .After the paw dorsal surface injection of MOR agonist , the pain threshold of CFA rats was increased, while that of normal rats exhibited no significant change .After the paw dorsal surface injection of MOR antagonist, the pain threshold of CFA rats was reduced , while that of normal rats had no significant change .Conclusion Under chronic inflammatory pain condition , DRG MOR expressionis enhanced , which participates in the regulation of chronic inflammatory pain , and may contribute to the prevention of further more serious pain .

Objective To explore the clinical effect of endoscopic-assisted intraoral reduction mandibuloplasty.Methods From January 2010 to December 2014,a total of 186 patients with prominent mandibular angles underwent one stage long-curved ostectomy combined with splitting corticectomy through an intraoral approach with endoscopic assistence according to preoperative design for reduction mandible three-dimensionally,and achieved reduced width of the lower face with smooth curve of mandibular edge.The distance between both gonions was measured and the complications recorded to evaluate the clinical effect of the surgery during follow-up.Results All the 186 patients had no complications of bleeding and infection.The mean distance between both gonions measurement was (117.3±2.5) mm before surgery and (102.6±2.3) mm after operation;it was reduced (14.1 ±2.4)mm.After 1 month to 2 years of follow up,the width of the lower face was reduced in the frontal view and the mandibular angle appeared natural and inconspicuous in the lateral view.The patients were satisfied with both their frontal and lateral appearances.Conclusions Intraoral approach mandibular ostectomy with endoscopic-assisted allows surgeons to perform accurate,safe and reproducible ostectomies and to recontour mandible symmetrically and reduce the complications.

Objective To characterize the cardiac magnetic resonance (CMR) features of peripartum cardiomyopathy(PPCM) and idiopathic dilated cardiomyopathy(IDCM), and to explore the value of MRI in the diagnosis of PPCM. Methods Ten cases of PPCM and 10 cases of Idiopathic dilated cardiomyopathy (IDCM) were included in this study. With 1.5 T MRI scanner, the heart shape (atrioventricular size, hypertrabeculation, thickness of the thinnest ventricular wall), function (ventricular wall movement and the overall function), cardiomyopathy perfusion were comprehensively evaluated. Paired samples t?test and Fisher exact probability method were used for statistical analysis. Results Between PPCM and IDCM group, there was no statistical significant difference in the atrioventricular size, cardiac output(CO), end diastolic volume(EDV), ejection fraction (EF), end systolic volume (ESV) and stroke volume (SV) (P>0.05). IDCM and PPCM group both showed ventricular wall thinning on MRI, with 4 cases of PPCM and 3 cases of IDCM presenting hypertrabeculation in the left ventricular apex. Seven cases of PPCM and 4 cases of IDCM depicted left ventricular local dysfunction, while 3 cases of PPCM and 6 cases of IDCM had abnormal integral movement. Two cases of PPCM appeared local delayed enhancement, while 4 cases of IDCM showed intramural delayed enhancement. After one year of follow?up, heart function recovered in 10 cases of PPCM and 4 cases of IDCM. Conclusions MRI diagnosis using multiple sequences is an ideal method in the evaluation of PPCM. Although there were no differences in cardiac morphology and function between PPCM and IDCM, the prognosis of PPCM is better than IDCM.

Objective To explore the high-risk factors of metabolic bone disease (MBD) in premature infants by retrospective analysis of the clinical data so as to provide evidence for optimal clinical management. Methods Clinical data of premature infants with birth weight<1500 g admitted in our hospital from January 2016 to December 2017 were retrospectively analyzed. Infants with serum alkaline phosphatase ( ALP )>500 IU/L and blood phosphorus <1. 5 mmol/L were selected as MBD group and premature infants with birth weight <1500 g were selected randomly as non-MBD group. General data, pulmonary surfactant, continuous positive airway pressure, mechanical ventilation, start time of enteral nutrition, parenteral nutrition ( PN) time, breast feeding time and breast milk fortifier adding, drug usage, hospitalization time and complications were re-corded and compared between the two groups. Results A total of 440 premature infants with birth weight<1500 g were admitted to the hospital during the study period. 58 [ 13. 2％ ( 58/440) ] infants were enrolled in the MBD group, among which infants with birth weight<1000 g accounting for 56. 9％ ( 33/58) . High birth weight (OR=0. 62, 95％ CI:0. 389-0. 990) was an independent protective factor of MBD in premature in-fants. The higher the birth weight, the lower the risk of MBD in premature infants. The longer duration of breast feeding time ( OR= 2. 191, 95％ CI:1. 628-2. 950) , later initial time of enteral feeding ( OR=2. 695, 95％CI:1. 710-4. 248), longer duration of PN (OR=6. 205, 95％ CI:3. 359-11. 463) time, longer duration of respiratory supporting time ( OR=1. 046, 95％ CI:1. 026-. 067) , longer hospital stay time ( OR=1. 703, 95％ CI:1. 109-2. 615) and small for gestational age ( OR=2. 965, 95％ CI:1. 163-5. 658) were inde-pendent risk factors of MBD in premature infants. The duration of PN was the most important independent risk factor of MBD in premature infants (OR=6.205, 95％ CI: 3.359-11.463). Conclusion Multiple factors can lead to MBD of premature infants. The high birth weight is an independent protective factor of MBD and the duration of PN is the most important independent risk factor of MBD in premature infants.

Objective:To explore the value of cardiovascular MR (CMR) T 1 mapping in evaluating myocardial injury in patients recovered from COVID-19. Methods:The clinical and image data of 15 patients with COVID-19 (9 with moderate clinical manifestation, 6 with severe clinical manifestation) who underwent CMR screening at 3 months after being discharged from the Second People′s Hospital of Fuyang City during May 2020 to June 2020 were prospective collected. Fifteen COVID-19 patients were selected as case group, and another 11 healthy volunteers were selected as control group. A standardized CMR protocol included cine, native and enhanced T 1 mapping, late gadolinium enhancement (LGE). Cardiac functional parameters, native T 1 value of left ventricular and extracellular volume fraction (ECV) were measured. One way ANOVA was used to assess the difference between CMR parameters among moderate and severe manifestation groups and control group, and LSD- t was used to assess the difference between the three groups. Results:LGE value was negative in all subjects. ECV values were higher in recovered COVID-19 patients with either moderate (27.9%±2.7%) or severe manifestation (30.0%±3.7%) than control group (23.2±1.9%) ( P<0.05); there was no significant difference of ECV values between recovered COVID-19 patients with moderate and severe manifestation ( P=0.100). There was no difference of native T 1 values and other functional and morphologic parameters of left ventricular and right ventricular among recovered COVID-19 patients with moderate and severe manifestation and control group ( P>0.05). Conclusion:CMR myocardial tissue ECV increase in patients who recovered from COVID-19, suggesting subclinical myocardial injury.

Objective To investigate the effect of electroacupuncture with low frequency on pain sensitization of neuropathic pain rats,and the possible mechanism of regulating peripheral pain sensitization. Methods Rat neuropathic pain model was established with the right L5 spinal nerve ligation. Zusanli (ST36) and Kunlun (BL60) were selected for electroacupuncture intervention. Mechanical allodynia, and the levels of stransient receptor potential vanilloid type 1 (TRPV1) and substance P (SP) in ipsilateral L5 and L4 dorsal root ganglion (DRG) were tested. A further validation experiment with TRPV1 agonist 6'-IRTX was carried out. Results Rats suffered from L5 spinal nerve ligation showed obvious pain sensitization. The levels of TRPV1 in ipsilateral L4 DRG and SP in ipsilateral L5 DRG were significantly elevated.Electroacupuncture with low frequency significantly relieved pain sensitization, and suppressed TRPV1 and SP increase. 6'-IRTX intraperitoneally administered significantly counteracted the anti-pain sensitization action of electroacupuncture with low frequency. Conclusion Electroacupuncture with low frequency is effective on neuropathic pain by intervening pain sensitization, which may be related to the regulation of DRG TRPV1 and SP.