1.Study on Neural Co-activation during Human Upper Limb Muscle Fatigue Based on Surface Electromyography
Chinese Journal of Sports Medicine 2017;36(4):290-295
Objectives To observe the co-activation phenomenon during exercise fatigue induced by the proximal muscles on the upper limbs.Methods Sixteen undergraduates not majoring in sports participated in this study,and their left arms were chosen as the observed arms and right arms were selected as the weighted arms.The weighted arm was alternatively in the state of relaxation without any load and fatigue after bending and extending elbow joints to uphold a 5 kg dumbbell.However,the observed arm kept weighing a 4 kg dumbbell with 90 degrees elbow flexion until the muscles were exhausted.The surface electromyography of biceps brachii and triceps brachii of the observed arms was measured using the ME6000.And the integrated surface electromyography (IEMG),root of mean square (RMS),mean power frequency (MPF)and median frequency (MF)were further analyzed.Results The IEMG and RMS of biceps brachii and triceps brachii of the observed arms increased gradually after the exercise began (P<0.05)regardless of in the relaxed state or in the in the state of weighing a 5 kg dumbbell for the weighted arm,but in the state of weighting a 5 kg dumbbell the IEMG and RMS increased more significantly (P<0.01),Meanwhile the electrical activities of the triceps brachii as an antagonistic muscle were intensively inhibited.The changes of MPF and MF of biceps brachii in the observed arms were more significant in the state of exercise fatigue than in the relaxed state (P<0.01),but without such an impact on the triceps brachii.Conclusions The fatigue in one arm can trigger contingent changes in sEMG time domain and frequency domain indexes of its contralateral parallel muscles,suggesting that sEMG changes of upper limb proximal muscles have the co-activation effect.
2.miR-200 family and its mechanism
Journal of International Oncology 2011;38(7):486-489
MiR-200 family is a cluster of miRNAs closely linked to EMT. The miR-200 family contains miR-200a, miR-200b, miR-200c, miR-141 and miR-429. Many studies have shown that miR-200 family are key regulators of EMT and determine the epithelial phenotype. They are important to both EMT development and tumor progression. This paper reviews the advancement in the research of miR-200 family and its mechanism.
3.Comparison study of AngⅡ induced cardiac hypertrophy model in TR3+/+ and TR3-/- mice by echocardiography
Chinese Journal of Ultrasonography 2012;21(6):521-525
ObjectiveTo compare of the thickness of left ventricular wall of Ang Ⅱ induced cardiac hypertrophy model in both TR3 konock-out C57BL/6 mice (TR3-/- mice) and wild type C57BL/6 mice (TR3+/+ mice) by high frequency ultrasound,combined with experimental research to discuss if TR3 take part in the process of cardiac hypertrophy.Methods26 TR3 -/- mice and 33 TR3 +/+ mice were randomized to 2 groups respectively:TR3+/+ + AngⅡ group (27 mice),TR3+/+ + PBS group(6 mice),TR3-/- + Ang Ⅱ group(20 mice),TR3-/- + PBS group(6 mice).Micro-pumps with AngⅡ or PBS were placed into the subcutaneous tissue of mice to construct hypertension model in 4 weeks.Interventricular septum enddiastolic thickness (IVSd) and left ventricular posterior wall end-diastolic thickness (LVPWd) were measured by echocardiography 2 days before operation and every week after operation until 4 weeks.Then,mice were killed and mice cardiomyocytes were isolated and detected in lab (HE dyeing test,Western blotting).Results①Echocardiography:before operation,IVSd and LVPWd was not statistically different between TR3+/+ group and TR3-/- group( P >0.05).1 - 2 weeks after operation,IVSd and LVPWd had peaked in both TR3-/- + Ang Ⅱ group and TR3 +/+ + Ang Ⅱ group,IVSd and LVPWd in TR3 +/+ + Ang Ⅱgroup were significantly thicker than control group (TR3 +/+ + PBS group) ( P <0.05),IVSd and LVPWd in TR3-/-+ AngⅡ group were slightly thicker than control group (TR3-/- + PBS group) ( P <0.05).Compared with TR3-/- + Ang Ⅱ group,IVSd and LVPWd in TR3+/+ + Ang Ⅱ group were markedly increased( P <0.05).After 4 weeks operation,IVSd and LVPWd of all 4 groups were not statistically different than that in the 2nd week.②HE dyeing test:The cell size of cardiomyocytes in TR3+/+ mice increased significantly after Ang Ⅱ treatment,while TR3-/- mice did not.③ Western blotting:Ang Ⅱ promoted TR3 expressions in TR3 +/+ mice( P <0.05).ConclusionsTR3 do take part in the process of Ang Ⅱ induced cardiac hypertrophy in mice and it is a key factor in this process.
4.Analysis of risk factors for postoperative recurrence of chronic subdural hematoma
Chinese Journal of Trauma 2012;28(5):422-425
ObjectiveTo investigate the clinical epidemiologic characteristics of chronic subdural hematoma and risk factors for its recurrence so as to offer scientific basis for treatment and prognostic evaluation. MethodsA retrospective study was done on clinical data of 150 adults with chronic subdural hematoma from the Traumatic Brain Injury Database of Neurosurgery Department of General Hospital of Tianjin Medical University to analyze the clinical characteristics and the postoperative recurrence factors of the chronic subdural hematoma.ResultsHematoma volume of the patients in the recurrence group was more than that in the non-recurrence group.Age > 80 years and brain atrophy were two independent risk factors for postoperative recurrence of the chronic subdural hematoma.The recurrence rate was declined with the decrease of hematoma density on CT.The recurrence rate of the chronic subdural hematoma in the high-density group was significantly higher than that in the low-and iso-density groups. ConclusionsPreoperative hematoma volume,onset age,brain atrophy and hematoma density on CT are significantly correlated with the postoperative recurrence of the chronic subdural hematoma.A detailed clinical and radiological evaluation is of great importance for the treatment and prognostic evaluation of the chronic subdural hematoma.
5.Advances in Studies on Missed Diagnosis of Intestinal Polyps and Related Factors in Colonoscopic Examination
Chinese Journal of Gastroenterology 2016;21(2):115-117
In recent years,the incidence of colorectal polyps and colorectal carcinoma showed a trend to increase gradually. Statistical analysis demonstrated that 80% of colorectal carcinoma were developed from colorectal adenoma,and adenomatous polyps accounted for 1 / 2-1 / 3 of colorectal polyps. Endoscopy is the golden standard for examining intestinal lesions,yet it is not completely correct and certain missed diagnosis has occurred. Factors causing missed diagnosis of colonoscopy include lesion factors and non-lesion factors. This article reviewed the advances in studies on missed diagnosis of intestinal polyps and related factors in colonoscopic examination.
6.Electromyographic features of agonists and antagonist muscles of the knee joints during maximal and submaximal isokinetic fatigue
Chinese Journal of Tissue Engineering Research 2015;(33):5344-5350
BACKGROUND:The power output of the human joints depends on the activation of agonists and antagonist muscles around the joints, and the antagonist muscle is involved in physical activity in a co-activated manner, thereby helping to maintain joint stability. But there are less reports on the central nervous system strategies of antagonist co-activation under different muscle contraction modes. OBJECTIVE:To observe the characteristics and differences of surface electromyography (sEMG) of agonists and antagonist muscles of the knee joints during maximal and submaximal isokinetic exercises until fatigue. METHODS:Sixteen students were enroled, who developed the right knee joint fatigue induced by the Biodex isokinetic equipment, and simultaneously sEMG activities of vastus medialis, vastus lateralis and biceps femoris were recorded by the myoelectrical equipment. The RMS (%) and mean frequency were selected to analyze sEMG characteristics. RESULTS AND CONCLUSION:In the maximal isokinetic fatigue, the peak torque was decreased by 40.3% (P < 0.05) and the sEMG activity of agonists gradualy increased and then declined, but the sEMG activity of antagonists kept constant. In the submaximal isokinetic fatigue, the peak torque was decreased by 40.0% (P < 0.05), the sEMG activity of agonists gradualy increased (P < 0.05), and however the sEMG activity of the antagonists initialy increased and then decreased. The RMS and mean frequency of vastus medialis and lateralis as antagonists at selected reciprocal contractions showed no significant changes (P > 0.05). These results suggest that in the different intensities of isokinetic fatigue, the central nervous system employs different neural strategies on agonists and antagonists.
7.Effect of fondaparinux sodium in the prevention of deep vein thromboembolism after surgery on lower limbs
Chinese Journal of Biochemical Pharmaceutics 2016;36(8):68-70
Objective To study the clinical efficacy of fondaparinux sodium in the treat of deep vein thromboembolism after the surgery on lower limbs.Methods 83 cases of patients with lower extremity surgery from Jan 2013 to May 2015,were randomly divided into experimental group(42 cases) and control group(41 cases),the patients in experimental group were injected subcutaneously with fondaparinux sodium 2.5 mg,one time a day,for five days and the patients of control group administrated orally with rivaroxaban 10 mg, one time a day, for five days.All patients accepted the ultrasonic examination by Doppler’ s method before the experiment, seven days and one month later after the experiment.The occurrence of deep vein thromboembolism of all patients was counted,including Proximal thrombosis,Distal thrombosis and Total venous thrombosis,and recorded the occurrence of adverse reaction-subcutaneous hemorrhage.Results One case(2.38%)of deep vein thrombosis was appeared in the experimental group,and that was significantly lower than that of the control group seven case ( 17.07%, P <0.05 ) .Meanwhile, there was no patient observed adverse reaction in experimental group, while two cases were observed in control group ( P <0.05 ) .Conclusion Fondaparinux showed better clinical efficacy than rivaoxaban,and caused fewer adverse reaction.We can conclude that it is safe and effective for the treatment of deep vein thrombosis in patients accepting the lower limbs surgery.
8.Vitamin D and cerebral infarction
International Journal of Cerebrovascular Diseases 2016;24(4):356-359
Vitamin D is a group of steroid hormones.Studies in recent years have shown that vitamin D is associated with the incidence of cerebral infarction,the severity of infarction,and functional outcome.In addition to the indirect effect of vascular risk factors,vitamin D may also play the direct protective effect by inhibiting inflammation and oxidative stress after cerebral infarction.
9.Compilation ideas on TED-Med Viewing, Listening & Speaking
Chinese Journal of Medical Education Research 2016;15(9):936-939
TED-Med Viewing, Listening&Speaking is compiled to serve academic audio-visual-oral English teaching in medical colleges. This paper elaborates some compilation ideas concerning this text-book. First, both the urgent needs of academic English teaching and the unique advantages of TED speech are the major stimulus to compiling this textbook. Second, its compiling philosophy adheres to learning centered, meaningful input. Third, compiling process is divided into three stages-preparation, writing and evaluation. Third, compiling principles includes four aspects: language and medical knowledge integrate
organically, the text and the task are authentic; proficiency training approaches are scientific; and the text-book is suitable for autonomous learning. Forth, the main content covers four medicine-related themes-humanity, health, disease, science and technology; each theme consists of three sub topics with 12 units (topics) in total; the content is interesting, informative and reflective. These compilation ideas prove to be scientific and feasible demonstrated by English teachers and medical experts. TED-Med Viewing, Listening&Speaking is expected to be completed and published earlier in order to promote academic English teach-ing and research in medical colleges.
10.Microsurgical treatment of ependymoma in conus medullaris and cauda equina
Chinese Journal of Postgraduates of Medicine 2016;39(5):397-400
Objective To explore the microsurgical technique of ependymoma in conus medullaris and cauda equina. Methods Sixteen patients with ependymoma confirmed by pathology after operation in conus medullaris and cauda equina were analyzed retrospectively for their clinical manifestations, imaging features and microsurgical treatment. Results All patients conducted preoperative MRI, and total tumor resection was achieved in 14 patients and subtotal resection in 2 patients. The pathological examinations confirmed the tumor as myxopapillary ependymomas in 7 patients. Symptoms of fifteen patients were alleviated significantly after operation. One patient had urine retention after operation and was gradually restored 1 week after operation. All patients were followed up for 1-3 months, and there was no case of recurrence. Conclusions Ependymoma in conus medullaris and cauda equina is rare and easily misdiagnosed, with no specific clinical manifestations. MRI should be conducted as soon as possible to identify the diagnosis. Microsurgical treatment is an effective method for ependymoma in conus medullaris and cauda equina.