Objective To investigate the effect of electric stimulation applied during absolute refractory period on contraction and relaxation and Ca 2+ transient of ventricular myocytes from normal guinea-pigs. Methods The ventricular myocytes of guinea-pigs were obtained by enzyme digesting, and the extent of the contraction and relaxation and Ca 2+ transient were recorded through the motion edge detection system. The Ca 2+ transient was reflected by fluorescence ratio (360/380) ( F 360/F 380). Results The ventricular myocytes from the normal guinea-pigs: ①The contraction extent of guinea-pig ventricular myocytes increased by (16.55?5.49)%. The peak velocity of shorting (contraction) and the peak velocity of relengthening (relaxation) increased by (17.43?7.08)% and (19.74?9.08)%, respectively(n=10); ②The extent of F 360/F 380 increased (25.79?6.88)%. The peak velocity of F 360/F 380 increased by (29.47?9.25)% and (22.52?7.81)% during shortening and relengthening, respectively(n=10). The ventricular myocytes from failure guinea-pigs: ①The contraction extent of guinea-pig ventricular myocytes increased by (15.53?5.31)%. The peak velocity of shortening (contraction) and the peak velocity of relengthening (relaxation) increased by (10.60?3.02)% and (23.32?8.26)%, respectively(n=6); ②The extent of F 360/F 380 increased (16.82?7.03)%. The peak velocity of F 360/F 380 increased by (16.27?5.91)% and (10.32?2.46)% during shorenting and relengthening, respectively(n=6). Conclusion Appropriate electric stimulation applied during absolute refractory period might strengthen the contracting and relaxing function of normal and failing ventricular myocytes in guinea-pigs.

Objective To investigate the value of multi planar reconstruction (MPR) with 64-slice spiral CT for diseases of lumbar disc, vertebra and accessory etc. Methods 50 cases of MPR were compared with 64-slice spiral CT on protrusion of lumbar disc at radom. Results MPR with 64-slice spiral CT showed not only the protrusion of lumbar disc but also the diseases of the vertebra,the accessory, and the adjacent tissue. Conclusion MPR with 64-slice spiral CT has a good value in diagnosis of disease of lumbar disc, vertebra, accessory and the adjacent tissue.

AIM: To investigate the feasibility of transplanting endothelial progenitor cells(EPCs) obtained from spleen in vascular endothelium repairmen after vascular injury.METHODS: EPCs were isolated by using a Ficoll density gradient centrifugation,and were cultured in plate.The endothelial characteristics of EPCs were identified by immunochemical staining and fluorescent labeling.Dil-Ac-LDL labeled spleen-derived EPCs were transplanted into the rats by intravenous injection directly after induction of arterial injury and again 24 hours later.Rats received FITC-labeled lectin intravenously before euthanasia.The distribution of fluorescent labeled EPCs was traced.The morphology of arterial intima and media was studied by optical microscopy and image analysing system.RESULTS: The adherent cells were considered EPCs that showed spindle shape and form blood-siland-like structures during development.The adherent cells had many endothelial characteristics.Fluorescent labeling showed that the intravenously injected EPCs specifically restricted to the vascular injury site,and lectin binding confirmed the endothelial phenotype.The ratio of neointimal/media area in EPCs transplantation group was obviously reduced than that in injury group and M199 group(0.82?0.09 vs 1.52?0.21,1.48?0.19,P

Objective To explore the clinical features of sentinel polyps (rectal polyps with proximal colon carcinoma) and its correlation with proximal colon carcinoma.Methods From January 2003 to December 2013,the clinical features of 963 hospitalized patients with rectal polyps were retrospectively analyzed.According to whether the patient with colon carcinoma,the clinical data of rectal polyps patients were divided into pure polyps group (n=855) and sentinel polyps group (n 108).The characteristics under endoscopy,clinical pathological features,treatment and prognosis of the two groups were observed.Chi square test was performed for differences comparison between groups.Results The length of stay in hospital of 963 patients was from four to 33 days,the average age was (49.7 ± 9.4) years,and the majority of the patients were male (n=610,63.3％).A total of 785 patients (81.5％) had non-specific abdominal symptoms,such as frequency or habit change of defecation,hematochezia,abdominal pain,abdominal distension.The relatives within three generation of 78 patients (8.1 ％) were diagnosed with tumor and some relatives of the patients diagnosed with familial adenomatous polyposis (2.2％,21/963).The positive rate of tumor marker of sentinel polyps group was higher (69.4％,75/ 108) than that of pure polyps group (6.8％,58/855; x2 =316.285,P＜0.01).The proximal colon carcinoma of patients with sentinel polyps appeared as neoplasma with circumferential growth,there was no specific appearance between distal rectal polyps and proximal colon carcinoma.When compared with pure polyps group,most polyps of sentinel polyps group were in maximum diameter over 1 cm (61.1％ (66/108) vs 46.9％ (401/855)),multi polyps (n＞5,38.9％ (42/108) vs 11.8％ (101/855)) and adenomatous polyp (83.3％ (90/108) vs 35.6％(304/855),x2=7.752,55.595 and 90.544,all P＜ 0.01).Majority of the proximal colon carcinoma with rectal polyps was papillary adenocarcinoma and tubular adenocarcinoma which was account for 75.9％ (82/108).Some were mucinous carcinoma and signet ring cell carcinoma.Most of the proximal colon carcinoma with rectal polys did not penetrate the serosa layer (Duk A-+Duk B,59.3％,64/108) and with little distant metastasis (Duke D,17.6％,19/ 108).Ninty-five point six percent (817/855) of patients with pure polyps underwent endoscopic treatment and all of them were cured and discharged.Forty-one point seven percent (45/108) of patients of sentinel polyps group accepted the radical operation and 19.4％ (21/108) received endoscopic submucosal dissection.Conclusions If multiple,maximum diameter over 1 cm and adenomatous rectal polyps were detected under colon endoscope,the possibility of carcinogenesis of the polyps or the proximal colon should be awared.If the endoscope is difficult to go further or the patient can not tolerate the whole colon examination,the patient should be followed up in short-term and complete the whole colon examination.

Objective:To investigate the animal model of guinea pig chronic heart failure and compensatory hypertrophy. Methods:Thirteen chronic heart failure models were made by placing a constricting band around the ascending aorta of guinea pigs,raised in the same house of 10 normal guinea pigs. The contrasting indexes in 6 weeks include: clinical features, hemodynamics, the mass ratio of ventricular over body, the width of left ventriculat hypertrophy. Results:One model died, 4 models without dyspnea showed increasing in left ventricular pressure and the mass ratio of ventricular over body, whereas the left ventricular end diastolic pressure showecl no significant different. Eight models with dyspnea showed striking increasing in left ventricular pressure and left ventricular end diastolic pressure, as well as the mass ratio of ventricular over body and the width of left ventricular hypertrophy. Conclusion:The animal model of guinea pig chronic heart failure and compensatory hypertrophy may be formed by constricting the ascending aortas of guinea pigs for 6 weeks.

Objective To investigate the role of ECRG2,a novel tumor suppressor gene,in spindle assembly checkpoint. Methods Using siRNA approach to deplete the expression of ECRG2, using immunofluorescence to test the distribution of ECRG2,using Western blotting to examine the expression cell cycle proteins.Results ECRG2 localized to centrosomes during interphase and kinetochores during mitosis.Further analysis revealed that ECRG2 participates in the spindle assembly checkpoint.Depletion of ECRG2 abolished the spindle assembly checkpoint.Conclusion Our results indicated that ECRG2 is important for ensuring spindle assembly checkpoint,accurate chromosome segregation,and its depletion may contribute to chmmosome instability and aneuploidy in human cancers.

Objective To observe the effects of electroacupuncture on the expressions of autophagy related protein Beclin-1 and apoptosis related protein p53 of hippocampus in rats;To explore the mechanism of electroacupuncture on Alzheimer's disease (AD).Methods The rats were randomly divided into the normal group, the sham-operation group, the model group, and the electroacupuncture treatment group. “Baihui” and “Yongquan” points were taken for electroacupuncture treatment and the treatment course was 7 days. The rats were treated once a day for 4 courses. Changes in morphology and number of Nissl positive cells were examined by Nissl staining in hippocampal CA1 regions. Expressions of Beclin-1 and p53 protein were determined by Western blot analysis.Results Number of Nissl positive cells in CA1 region of the model group was significantly less than that of normal group (P<0.01). After electroacupuncture treatment, number of pyramidal cells and expression of Nissl body significantly increased (P<0.05). Expression of Beclin-1 decreased, while expression of p53 increased in the hippocampus of the model group, compared with that in the normal group (P<0.05). However, electroacupuncture treatment could significantly upregulate the expression of Beclin-1 protein (P<0.01), but downregulate the level of p53 (P<0.05).Conclusion Electro-acupuncture treatment could fight against Aβ-induced neuronal apoptosis, and improve the morphological changes of AD’s hippocampus.

Objective To investigate audiological characteristics of patients with intact tympanic membranes and conductive or mixed hearing loss .Methods A retrospective study was carried out among 30 patients (42 ears) with intact tympanic membranes and conductive or mixed hearing loss who underwent exploratory tympanotomy . The preoperative outcomes of pure tone audiometry ,tympanometry ,resonant frequency of middle ear and temporal bone CT scan were analyzed .Results Among 42 ears ,30 ears with otosclerosis and 12 ears with ossicular chain dis-ruption were confirmed in exploratory tympanotomy ,but only 5 ears showed positive findings in CT scan .The mean thresholds of bone conduction ,air conduction and air -bone gap at frequencies of 0 .5 ,1 and 2 kHz were 27 .5 ± 1 .3 dB HL ,67 .0 ± 1 .8 dB HL ,39 .5 ± 1 .1 dB HL ,respectively .An analysis of tympanometric data of all patients re-vealed that 50% of all ears (21/42) were type A tympanograms ,42 .9% (18/42) were type As tympanograms ,and 7 .1% (3/42) were type Ad tympanograms .The mean of the resonant frequency of the middle ear in otosclerositic patients (1 079 .0 ± 67 .4 Hz) was significantly higher than ossicular chain disruption patients (633 .3 ± 43 .6 Hz) . Conclusion Otosclerosis is the most common in the patients with intact tympanic membranes and conductive or mixed hearing loss .The middle ear resonant frequency of otosclerositic patients is significantly higher than that of ossicular chain disruption patients .

AIM: To investigate the influences of electric stimulation applied during the absolute refractory period (ARP) on the cardiac function of normal rabbits and rabbits after myocardial infarction (MI) and to observe the regional effects of this electric stimulation. METHODS: 64 rabbits were randomly assigned to normal and MI groups and each group was then divided into the anterior and posterior groups. A thoracotomy was performed 4 weeks after MI in rabbits. One set of electrodes was inserted into the anterior and posterior wall of left ventricle of the anterior and posterior groups, respectively. Current pulses were delivered during the ARP (called CCM) during sinus rhythm in rabbits. The left ventricular systolic pressure (LVSP) and the left ventricular end diastolic pressure(LVEDP) as well as maximum positive and negative left ventricular pressure change (?dp/dt_(max)) were observed. RESULTS: In the normal and MI groups, LVSP, +dp/dt_(max) significantly increased, and LVEDP, -dp/dt_(max) were reduced during CCM stimulation compared with the baseline (P0.05). CONCLUSION: Electric stimulation delivered during the ARP significantly enhances the contractility and the relaxation of myocardium in normal rabbits and rabbits after MI, and the effects of CCM stimulation on heart are regional. [

AIM: To evaluate the mobilization of endothelial progenitor cells (EPCs) in mice peripheral blood during hindlimb ischemia alone or in combination with granulocyte colony stimulating factor (G-CSF). METHODS: Hindlimb ischemia was established in mice by surgical excision of both femoral arteries. Fluorescence-activated cell sorting (FACS) was used to detect the expression of cell-surface CD34 and vascular endothelial growth factor recepter-2 (VEGFR2) antigens. The ratio of double-positive cells for CD34 and VEGFR2 was regarded as the level of EPCs in peripheral blood. In G-CSF administration in combination with hindlimb ischemia group, the percentage of double-positive cells was also detected. RESULTS: As compared with control group, hindlimb ischemia increased the percentage of EPCs in mice peripheral blood. The hindlimb ischemia combined with G-CSF administration significantly enhanced the percentage of EPCs. CONCLUSION: Ischemia increases the number of EPC in peripheral blood. It may induce the migration of EPC from barrow to peripheral blood. By mobilizing barrow, G-CSF enhances this effect.