2.Effects of arachidonic acid on L-type calcium channel and its mechanism of antiarrhythmia
Chengyun LIU ; Guiqing CHEN ; Xiaojing GENG ; Xin CHEN ; Jingjing WAN
Chinese Journal of Emergency Medicine 2009;18(2):180-184
Objective To study the influence of arachidonic acid (AA) on L-type calcium channel in rabbits sin-gle cardiomyocyte and its mechanism of antiarrhythmia. Method The single ventricular cardiomyocyte was isolat-ed by using enzyme dispersion method and whole-cell clamp-patch technique was used to record L-type calcium current.All data were analyzed using ANOVA. Results AA inhibited Ica-L in a concentration-dependent manner. The application of 3 μmol/L, 10 μmol/L and 20 μmol/L arachidonic acid reduced the density of peak Ica-L from (10.79±0.93)pA/pF to (8.99±0.43)pA/pF to (7.60±0.35)pA/pF and to (5.60±0.30)pA/pF, respctive-ly (n=7, P<0. O1 ). The Ica-Lpartially resumed after washout. The AA up-shifted the I-V curves of Ica-L without changes of their shape,peak and reverse potentials. The AA also markedly shifted the inactivation curve to left, and prolonged the recorvery time from inactivation,but did not change the curve of calcium channel activation. Con-clustions By acceleration of L-type calcium channel inactivation and prolongation of recorvery time from inactiva-fion,arachidonic acid can reduce the calcium ion influe and prolong effective refractory period, playing the role of antiarrhythmia.
3.Comparison of two methods testing synergistic action of Reduning and cefoperazone sodium/sulbactam sodium on extensive drug resistant Acinetobacter bauman
Xin LI ; Guifang YANG ; Huayu CHEN ; Jie GENG ; Zhijie JIA
International Journal of Laboratory Medicine 2016;37(6):723-725
Objective To observe the results of broth dilution method and disc diffusion method to test the synergistic effect of Reduning and cefoperazone sodium / sulbactam sodium(SCF) on extensive drug resistant Acinetobacter bauman (XDR-AB) in vitro environment ,and compare their compliance to guide the clinical medication .Methods A total of 12 strains of XDR-AB from infec-tion patients in our hospital in 2015 were collected ,the strain was sub cultured .Firstly ,observe the minimum inhibitory concentra-tion (MIC) of SCF and Reduning on XDR-AB alone and in combination by broth dilution method .And then judge the synergy effects through calculation .Secondly ,the inhibition ring diameter and the synergy effects was detected using the disc diffusion meth-od .Results The MIC of Reduning and SCF in combination on XDR-AB was declined compared with them alone .The Fractional in-hibitory concentration of Reduning and SCF in combination on XDR-AB were equal or less than 0 .5 ,they had synergistic effect on XDR-AB .The inhibition ring diameter of Reduning was 10 mm tested by disk diffusion method .Different strains of XDR-AB on SCF bacteriostatic annulus diameter difference ,5 strains were 15 mm ,3 strains were 16 mm ,and 4 strains were 17 mm .Reduning and SCF appeared synergistic effect according to the inhibition ring diameter expanded when they effected on XDR -AB in combina-tion .Conclusion In vitro ,Reduning combined with SCF on XDR-AB has good synergistic effect .Compared with broth microdilution checkerboard dilution method ,disk diffusion method is more simple and convenient ,but it has a certain subjective on judging re-sults ,which is better to operate by experienced person .
4.Effects of early tracheostomy on patients with acute severe brain trauma
Geng ZHANG ; Mahong HU ; Yangbo CHEN ; Xin JIN ; Dingkun WANG
Chinese Journal of Trauma 2012;28(7):597-601
Objective To evaluate the effects of early and late tracbeostomy on patients with acute severe cerebral trauma.Methods In the retrospective study,167 patients with severe brain trauma ( GCS < 9 ) requiring prolonged mechanical ventilation ( MV ) were managed by percutaneous dilational tracheostomy (PDT) from May 2001 to December 2010.According to the transoral incubation MV duration,the patients were divided into the early tracheostomy (ET) group ( MV duration≤7 d,81 cases)and late tracheostomy (LT) group (MV duration > 7 d,86 cases).The basic clinical characteristics,pre-and post-PDT MV period,total MV duration,length of post-PDT ICU stay,length of ICU stay,length of hospital stay and mortality were compared between the two groups.Results The two groups showed no statistical differences in aspects of age,sex,acute physiology and chronic health evaluation Ⅱ (A-PACHE Ⅱ ) score,GCS,trauma index and craniotomy rate (P>0.05).Compared with LT group,ET group significantly shortened the pre-PDT MV period [ (5.16 ± 1.33 ) d∶ ( 1 1.64 ± 4.25 ) d,P < 0.01 ],post-PDT MV period ( median:15.0 d∶ 17.0 d,P < 0.05 ),total MV duration ( median:18.0 d∶26.0 d,P<0.05),length of post-PDT ICU stay (median:16.0 d∶21.0 d,P<0.01 ) and length of ICU stay (median:21.0 d∶32.0 d,P <0.01 ).But the two groups had no statistical differences concerning the length of hospital stay ( P > 0.05 ),ICU mortality ( 17% ∶ 14%,P > 0.05 ) and in-hospital mortality (25%∶28.4%,P >0.05).Kaplan-Meier curves showed that the frequency of MV and ICU stay rate within 60 days in ET group were significantly lower than those in LT group.Conclusions For patients with severe brain trauma,early tracheostomy shortens the duration of MV and length of ICU stay without affecting their prognosis.Thereby,tracheostomy can be performed at early stage when managing acute severe brain injury.
6.Periosteal flap of anterovent of digastric muscle-mandible to renovate laryngotracheal stenosis: an applied anatomical study
He-Xin CHEN ; Shi-Zhen ZHONG ; Geng XU
Journal of Southern Medical University 2000;20(6):553-554
Objective To explore a new surgical approach for the renovation of laryngotracheal stenosis. Methods the anatomical structures of the anteroventral portion of the digastric muscle along with the blood supply, innervation and periosteal coverage of the mandibular were investigated by observing 23(46 sides) cadaver. Results The anteroventral portion of the digastric muscle rise from the fossae digastrica at the angle of 30.4°±3.5°. Its length was (4.8+0.7) cm and the periosteal coverage averaged (111.6+28.2) mm2. The puncta of rami digastricus stats (2.4+0.7) cm from the arteriae submentalis. Mylohyoid nerve together with rami digastricus enters the muscular tissue. Conclusion Designed with reference to sternocleidomastoid clavicular periosteal flap, the periosteal flap of the anterovent of the digastric muscle-mandible may offer a new way for largngotracheal renouation.
7.Periosteal flap of anterovent of digastric muscle-mandible to renovate laryngotracheal stenosis: an applied anatomical study
He-Xin CHEN ; Shi-Zhen ZHONG ; Geng XU
Journal of Southern Medical University 2000;20(6):553-554
Objective To explore a new surgical approach for the renovation of laryngotracheal stenosis. Methods the anatomical structures of the anteroventral portion of the digastric muscle along with the blood supply, innervation and periosteal coverage of the mandibular were investigated by observing 23(46 sides) cadaver. Results The anteroventral portion of the digastric muscle rise from the fossae digastrica at the angle of 30.4°±3.5°. Its length was (4.8+0.7) cm and the periosteal coverage averaged (111.6+28.2) mm2. The puncta of rami digastricus stats (2.4+0.7) cm from the arteriae submentalis. Mylohyoid nerve together with rami digastricus enters the muscular tissue. Conclusion Designed with reference to sternocleidomastoid clavicular periosteal flap, the periosteal flap of the anterovent of the digastric muscle-mandible may offer a new way for largngotracheal renouation.
8.A comparison between over-the-toe plaster slab and off-loading forefoot shoes following hallux valgus correction
Xiang GENG ; Jiazhang HUANG ; Xin MA ; Xu WANG ; Chao ZHANG ; Li CHEN ; Chen WANG
Chinese Journal of Tissue Engineering Research 2017;21(26):4234-4239
BACKGROUND: Operative correction of hallux valgus is one of the most procedures in foot and ankle department, but postoperative plaster slab immobilization often brings great inconvenience and pain. Off-loading forefoot shoes can theoretically help them to do activities off bed early, and prevent loading on the forefoot during walking. But its advantages and disadvantages compared with plaster slab are still unknown.OBJECTIVE: To compare the clinical effects of over-the-toe plaster slab and off-loading forefoot shoes after hallux valgus correction.METHODS: Patients with hallux valgus undergoing distal Chevron osteotomy or Scarf osteotomy in the Huashan Hospital of Fudan University between May 2012 and October 2013 were retrospectively reviewed. Group A patients had a below-knee and over-the-toe plaster slab while Group B had an off-loading forefoot shoe applied after surgery.Radiological assessment was done at 6 weeks postoperatively. Immobilization was removed once bone union was indicated. Clinical scales and subjective satisfaction investigation were performed at final follow-up, and complications during follow-up were noted. All values between groups were analyzed statistically.RESULTS AND CONCLUSION: Totally 125 patients (157 feet) were completely followed up, including 83 patients (95 feet) in Group A and 42 patients (62 feet) in Group B. There was no significant difference in demographics, pre-and-post operative radiological assessments, clinical scale, union time or general satisfaction rates between two groups. However,Group B patients had less chance to suffer metatarsophalangeal joint or inter-phalangeal joint stiffness, restricted ankle motion and supra-ankle pains of operated side in comparison with Group A (P < 0.05), and were more willing to accept the same treatment if they could choose again (P < 0.05). Compared with the plaster slab, the application of off-loading shoes not only maintains correction level, but also reduces such complications as stiffness or restricted motion of the joint, limb pains and so on, which makes patients more likely to accept, and should be given priority to in the rehabilitation following hallux valgus correction.
9.Significance of intra-and extraosseous edema accompanying benign tumors and tumor like diseases
Haisong CHEN ; Xiaofei LI ; Qing GENG ; Xin SUN ; Weihua FENG ; Limin TANG
Chinese Journal of Radiology 2015;49(3):199-202
Objective To explore the incidence and significance of intra-and extraosseous edema accompanying benign tumors and tumor like diseases.Methods Imaging studies including MR,CT and plain radiograph were retrospectively reviewed in 245 cases of benign osseous tumors and tumor like diseases proved by pathology(borderline tumor,cases associated with pathological fractures,cases with lesions of skull were excluded from the study).The incidence of bone marrow and soft tissue edema were defined on T2WI with fat suppression on MRI in all the cases.x2 test was performed for the incidence rate of edema in the benign tumors and tumor like diseases.The pre-operative diagnoses were reviewed,and the influence of edema to the differential diagnosis between the benign and malignant was analyzed.Results The total incidence of bone marrow and soft tissue edema associated with benign tumors and tumor like diseases was 37.1% (91/245),which included Langerhans cell histiocytosis 85.2% (23/27),osteoblastoma85.0% (17/20),osteoid osteoma93.6% (29/31),ehondroblastoma 87.0% (20/23).There was no statistically significant difference of edema incidence among the above-mentioned four diseases.(x2=6.35,P> 0.05).Both cases of endosteal capillary hemangioma had edema around.No edema was found around the lesions of other kinds of diseases.41 of 91 cases (45.1%) with edema were misdiagnosed as malignant tumor by MRI pre-operatively.Conclusion The marrow and soft tissue edema is a common sign in the benign bone tumor and tumor-like diseases,and it is frequently seen in Langerhans cell histiocytosis,osteoblastoma,osteoid osteoma,chondroblastoma.
10.Expressions of MK2, HuR, and ICAM-1 in the pulmonary microvascular endothelial cells of the mouse with acute respiratory distress syndrome
Shen GENG ; Ting WU ; Xianmin MU ; Chen ZHANG ; Chenyang LIU ; Qiang YOU ; Xin SU
Journal of Medical Postgraduates 2016;29(4):342-347
Objective Intercellular adhesion molecule-1 (ICAM-1) plays an important role in mediating pulmonary infiltration of neutrophils .The aim of the study was to observe the expression of ICAM-1 and its potential regulators MK 2/HuR in pulmonary micro-vascular endothelial cells ( PMVEC ) in mice with acute respiratory distress syndrome ( ARDS) induced by lipopolysaccharide ( LPS) . Methods Ten 6-8 weeks old healthy C57BL/6 mice were randomly divided into an LPS and a control group of equal number , the former injected intraperitoneally with LPS diluted in 100 μL PBS while the latter with PBS only , both at 5 mg per kg of the body weight .At 24 hours after injection , all the mice were sacrificed .Real-time PCR was used to determine the mRNA expressions of HuR and ICAM-1 in the PMVECs, Western bolt employed to detect the protein expressions of MK2, HuR and ICAM-1, and flow cytometry adopted to measure the ICAM-1 expression on the surface of the PMVECs and pulmonary infiltration of neutrophils . Results The W/D ratio in the lung tissue of the mice was significantly lower in the LPS than in the control group (3.61 ±0.28 vs 6.16 ±0.40, P<0.05), while the rate of neutrophil infiltration markedly higher in the former than in the latter ([13.92 ±3.23]%vs [3.24 ±1.24]%, P<0.05).The mRNA and protein expressions of ICAM-1 in the PMVECs were significantly elevated in the LPS group as compared with that in the control (P<0.05), and so was the mRNA expression of HuR (P<0.05).No remarkable changes were observed in the expressions of total MK 2 and HuR proteins, but phosphorylated MK2 (p-MK2) and cytoplasmic HuR were increased in the LPS-stimulated mice. Conclusion Specific blockage or reduction of the HuR expression in PMVECs may lower the expression of ICAM-1, reduce neutrophil infiltration , and lessen pathophysiological changes in mice with ARDS .