Disease Outbreaks ; prevention & control ; Humans ; Influenza A Virus, H5N1 Subtype ; Influenza Vaccines ; Influenza, Human ; prevention & control

ObjectiveTo assess left ventricular (LV) twist in Beagle dogs with rapid-pacing induced heart failure by 3-dimensional speckle tracking imaging.MethodsSeventeen adult beagle dogs underwent rapid right ventricular pacing (RVP) to induce heart failure.Right ventricles were paced at 260 beats/min for 3 weeks.Apical full-volume acquisition of the LV was obtained in conscious animals at baseline and the end of 3-week rapid pacing.Peak LV apical rotation(AP-Prot) and basal rotation (MV-Prot) accompanied with peak twist (Ptw) and torsion were automatically calculated by TomTec 4D LV Analysis 3.0 software.The relation between LV twist and QRS duration was further studied.Results After 3 weeks of rapid ventricular pacing,AP-Prot,MV-Prot,Ptw decreased significantly [At-Prot:(13.96 ± 2.00) ° vs (5.85 ± 0.58)°；MV-Prot:(3.34± 0.38)° vs (2.13 ± 0.44)°； Ptw:(16.31 ± 2.01)° vs (7.08 ± 1.16)°,all P ＜0.05].Dogs with heart failure were divided into two groups according to the QRS duration:pQRSd group with QRS≥100 ms and nQRSd group with QRS＜100 ms.No significant difference was found in AP-Prot and MV-Prot between two groups ( P ＞0.05).In the pQRSd group,the peak of apical rotation occurred earlier than the peak of basal rotation [(162.89 ± 14.33) ms vs (91.43 ± 15.45) ms,P ＜0.05],which might resulted in further worsening of peak LV twist [pQRSd:(6.02 ± 0.74)° vs nQRSd:(7.91 ± 0.53)°,P ＜0.05].Conclusions LV twist dynamics was a good indicator of LV systolic function and had the potential to evaluate LV systolic dyssynchrony.

Objective To assess left ventricular (LV) twist in a rapid pacing induced heart failure canine model undergoing cardiac resynchronization therapy (CRT) by three-dimensional speckle tracking imaging (3D-STI).Methods Rapid right ventricular pacing (RVP) was utilized in 22 adult beagle dogs for 3 weeks to induce heart failure.Then 15 dogs received CRT for 2 weeks and others were treated as control.Apical full-volume acquisition of the LV was obtained in conscious animals at baseline,the end of 3-week RVP and the end of 2-week CRT.Peak LV apical (AP-Prot) and basal rotation (MV-Prot) along with peak twist (Ptw) and torsion (Ptor) were automatically calculated by TomTec 4D LV Analysis 3.0 software to identify the ideal parameter in predicting treatment response of CRT.Results After 2 weeks of CRT,LV ejection fraction(LVEF) increased and LV end-systolic volume(LVESV) decreased significantly in dogs with heart failure.CRT treatment response,defined as improvement of LVESV≥15％,was observed in 9 dogs.Significant difference was found in Ptw [(7.43 ± 0.61) vs (6.06 ± 0.89)°,P ＜0.05] and Ptor [(1.43 ± 0.45) vs (0.67 ± 0.36)°/cm,P ＜0.05] between responders and nonresponders.Ptw and Ptor predicted CRT response with satisfying sensitivity as 89％ and 85％,specificity as 83％ and 84％,respectively.Conclusions Peak twist and torsion evaluated by 3D-STI represented overall LV twist and demonstrated potential prediction value for treatment response of CRT.

Objective To investigate new parameters to predict the response to cardiac resynchronization therapy (CRT) by using real-time three-dimensional echocardiography (RT3DE) and speckle tracking imaging(STI). Methods Twenty-one adult beagle dogs were divided into three groups:group A (CRT group, n =10) ,group B (heart failure group, n =7) and group C (control group, n =4).Seventy patients who accepted CRT and were followed up 6 months after CRT were enrolled. Response to CRT was defined as a ≥15％ decrease in left ventricular end-systolic volume. RT-3DE parameters were the dispersion of time to minimum regional volume for 16 segments (Tmsv16-SD) ,and the ratio of Tmsv16-SD to R-R interval (SDI). STI parameters were the ratios of standard deviation of the time to peak radial and circumferential strain at midventricular level to R-R interval (Trs-6SD,Tcs-6SD). Results In experimental study,Tmsv-16SD, Trs-6SD, Tcs-6SD had negative relationship with left veutricular ejection fraction (r were - 0. 86, - 0.75, - 0.83 respectively, all P ＜0.01 ). Trs-6SD was the strongest predictor to CRT. A cut-off value of Trs-6SD≥12.2％ was able to predict response to CRT with a sensitivity of 83.3％ and a specificity of 100％. Clinical studies found SDI was the strongest predictor to CRT. A cut-off value of SDI≥6.55％ was able to predict response to CRT with a sensitivity of 80. 0％ and a specificity of 81.8％.Conclusions RT-3DE and STI can assess left ventricular dyssynchrony, and are promising methods to predict the response to CRT.

Objective: To investigate the expression of chemokine like factor 2 (CKLF2) mRNA in the rat myocardium after myocardial infarction(MI).Methods: In a rat model of MI, the myocardium surrounding the infarcted area was used for RNA preparation at different time points. After RT, competitive polymerase chain reaction amplification was performed to assess the expression of rCKLF2 mRNA. SAS Kruskal Wallis test was used for statistical comparisons. Results: The gene expression of rCKLF2 at mRNA level was significantly increased in the myocardium surrounding the infarcted area 3 days, 1 week, 2 weeks after infarction.Conclusion: It is possible that CKLF2 contributes to the pathophysiological process and needs to be further investigated.

OBJECTIVETo observe the effectiveness and safety of Tongyan spray composed of Chinese medicine for post-stroke dysphagia patients.

METHODOne hundred and twenty-two post-stroke dysphagia patients were randomly assigned to the treatment group (61 cases) and the control group (61 cases). Basic treatment was given to both groups, with Tongyan spray additionally used in oropharynx for the treatment group, and the placebo used for the control group. After 28-day treatment, the clinical effect and safety were evaluated according to the standard swallowing assessment (SSA) scale.

RESULTSOne patient dropped out in each group, and 120 patients reached the final analysis of the study. The total effective rate for the treatment group was 71.7% (43/60), higher than 46.7% (28/60) in the control group (P<0.05), and the improvement on SSA scores of the two groups were significantly different after treatment (P<0.05). For grade 1 dysphagia patients (completely depending on nasogastric tube), the effective rate of the treatment group was 40.9% (9/22), and 12.5% (2/16) of the control group, without significant difference (P>0.05), while the improvement of SSA score was significantly different between the two groups after treatment (P<0.05). For grade 2-3 dysphagia patients (oral and nasogastric tube feeding), the total effective rate of the treatment group was 89.5% (34/38), higher than 59.1% (26/44) in the control group (P<0.05), and also the improvement on SSA scores was significantly different between the two groups after treatment (P<0.05).

CONCLUSIONTongyan spray was an effective and safe method for post-stroke dysphagia patients.

Administration, Inhalation ; Aged ; Aged, 80 and over ; Clematis ; chemistry ; Deglutition Disorders ; drug therapy ; etiology ; Drugs, Chinese Herbal ; administration & dosage ; Female ; Ginger ; chemistry ; Humans ; Male ; Middle Aged ; Stroke ; complications ; Treatment Outcome

OBJECTIVETo study the relation of the structural remodeling processes and activation of calpain I.

METHODSFifteen dogs were randomly divided into three groups. The dogs in pacing group (n=5) and inhibitor group (n=5) were subjected to 3 weeks of rapid atrial pacing at 600 beats/min, control dogs (n=5) were in sham-operated group. The dogs in inhibitor group were administered intravenous N-Acetyl-Leu-Leu-Met (ALLM), a calpain inhibitor, and in pacing group and sham-operated group were administered intravenous DMSO. The activity of calpain I was measured by hydrolyzing Suc-Leu-Leu-Val-Tyr-7-amino-4-methyl-coumarin. The ultrastructure of atrium was examined by light and electron microscopy. TnT expression was assessed by Western blot. Echocardiography examination was performed in all the three groups.

RESULTSCalpain I activity was significantly increased in pacing group (2.3-fold, P<0.01), and decreased in inhibitor group (1.1-fold, P>0.05), compared to sham-operated group respectively. The percentages of myolysis were (76.7 +/- 5.9)% and (20.8 +/- 8.1)% in pacing group and inhibitor group respectively (P<0.01). TnT expression decreased in the rapid pacing-induced persistent atrial fibrillation, and these effects were inhibited by calpain I inhibitor ALLM. The area and volume of left atrium tended to increase after 3 weeks ALLM treatment in inhibitor group, but the change was not as prominent as in pacing group (P<0.05).

CONCLUSIONSALLM can decrease calpain I activity, and prevent canine atrial cardiomyocyte structural remodeling during atrial fibrillation. This study provided a capacity of atrial cardiomyocyte protection.

Animals ; Atrial Fibrillation ; metabolism ; physiopathology ; Atrial Function, Left ; Calpain ; antagonists & inhibitors ; metabolism ; Cardiac Pacing, Artificial ; Disease Models, Animal ; Dogs ; Heart Atria ; ultrastructure ; Myocardium ; metabolism ; Troponin T ; metabolism

Objective To study the effect ofT-786C polymorphism of endothelial NO synthase gene on cerebral circulation in smokers with aneurysmal subarachnoid hemorrhage. Methods Three hundred and ninety-four patients with aneurysmal subarachnoid hemorrhage were adopted in our study;smokers and nonsmokers were defined by 200 and 0, respectively, according to the smoking index (quantity of cigarettes per year). Transcranial color-coded Doppler (TCCD) was employed to detect the alterations of flow velocity of cerebral arteries. Genotyping ofT-786C was performed by using a newly developed allele-specific polymerase chain reaction. Degree of oxidative stress of these patients were evaluated by measuring the level of F2-isoprostane excretion in the urine. Results The mean flow velocity (Vm) of middle cerebral artery (MCA) and internal carotid artery (ICA) was obviously increased as compared with that of the other normal ones in most of the smokers. The Vm of MCA and ICA in nonsmokers was not obviously different as compared with the normal values. The 3 genotypes ofT-786C in smokers showed significant difference in Vm of MCA and ICA (P＜0.05); the Vm of CC genotype ([60.73±63.58] cm/s) was obviously increased as compared with that of TT ([95.8±53.5] cm/s) and TC ([93.6±51.6] cm/s) genotypes (P＜0.05). The 3 genotypes ofT-786C in nonsmokers did not show significant difference in Vm of MCA and ICA (P＞0.05). The level of F2-isoprostane excretion in smokers was significantly higher than that in nonsmokers (P＜0.05). Conclusion The T-786C polymorphism of endothelial NO synthase gene can increase cerebrovascular Vm by enhancing the cerebrovascular circulation of smokers with aneurysmal subarachnoid hemorrhage.

OBJECTIVETo study the mechanism of dichlorvos leading to hypospadia of rats.

METHODSFrom the 12th to the 17th day of conception, 20 pregnant female rats (the experiment group) were given 10 mg/(kg x d) dichlorvos, while another 10 (the control group) administered 1.5 ml 0.9% NaCl/day. Out of 88 male newborns of the 20 experimental mother rats, 22 had hypospadia, while out of the 33 male newborns of the 10 controls, none had the problem. Five hypospadia newborns from the experiment group and another 5 normal ones from the control group were raised to sexual maturity, and then their testes were excised and embedded in paraffin, and the tissue sections were analyzed by regular HE staining and SP immunohistochemical staining with Calretinin.

RESULTSHE staining showed that the number of Leydig cells in the testis tissues of the hypospadia rats decreased significantly compared with the normal ones, but no change was observed either in the number or in the morphology of the seminiferous tubules. Moreover, the Calretinin positive Leydig cells were reduced dramatically in the testes of the hypospadia rats.

CONCLUSIONPregnant female rats, when exposed to dichlorvos, may cause reduction of testis Leydig cells in their male offsprings. Thus the probable mechanism of rat hypospadia induced by dichlorvos may lie in the decrease of the testosterone level caused by damage to Leydig cells from dichlorvos toxicity.

Animals ; Cell Count ; Dichlorvos ; toxicity ; Female ; Hypospadias ; chemically induced ; pathology ; Leydig Cells ; pathology ; Male ; Pregnancy ; Rats ; Rats, Sprague-Dawley ; Testis ; pathology

BACKGROUNDAtrial fibrillation (AF) is accompanied by atrial structural remodeling. Calpain activity is induced during AF. To test a causal relationship between calpain activation and atrial structural changes, N-acetyl-Leu-Leu-Met (ALLM), a calpain inhibitor, was utilized in a canine AF model.

METHODSFifteen dogs were randomly divided into 3 groups: sham-operated group, control group and calpain inhibitor group; each with 5 dogs. Sustained AF was induced by rapid right atrium pacing at 600 beats per minute for 3 weeks. ALLM was administered at a dosage of 1.0 mg x kg(-1) x d(-1) in the calpain inhibitor group. Three weeks later, the proteolysis, protein expression of TnT and myosin, calpain I localization and expression and structural changes were examined in left atrial free walls, right atrial free walls and the interatrial septum respectively. Atrial size and contractile function were also measured by echocardiography.

RESULTSLong-term rapid atrial pacing induced marked structural changes such as enlarged atrial volume, myolysis, degradation of TnT and myosin, accumulation of glycogen and changes in mitochondrial shape and size, which were paralleled by an increase in calpain activity. The positive correlation between calpain activity and the degree of myolysis (r(s) = 0.90 961, P < 0.0001) was demonstrated. In addition to structural abnormalities, pacing-induced atrial contractile dysfunction was observed in this study. The pacing-induced atrial structural alterations and loss of contractility were partially prevented by the calpain inhibitor ALLM.

CONCLUSIONSActivation of calpain represents key features in the progression towards overt structural remodeling. Calpain inhibitor, ALLM, suppressed the increased calpain activity and reversed structural remodeling caused by sustained atrial fibrillation in the present model. Calpain inhibition may therefore provide a possibility for therapeutic intervention in AF.

Animals ; Atrial Fibrillation ; pathology ; Calpain ; antagonists & inhibitors ; Cysteine Proteinase Inhibitors ; pharmacology ; Disease Models, Animal ; Dogs ; Heart Atria ; pathology ; ultrastructure ; Myosins ; analysis ; Troponin T ; analysis