DIRECT CAROTID WALL SHEAR STRESS IN ACUTE CORONARY SYNDROME PATIENTS DECREASED AFTER ONE MONTH MEDICAL MANAGEMENT

Fuente Fuente, Carlos;Montes Gil, Antonio;Periel Piquer, Montserra

Autonomic Nerve Activity and Blood Pressure in Ambulatory Dogs

Background The relationship between cardiac autonomic nerve activity and blood pressure (BP) changes in ambulatory dogs is unclear. Objective To test the hypotheses that simultaneous termination of stellate ganglion nerve activity (SGNA) and vagal nerve activity (VNA) predisposes to spontaneous orthostatic hypotension and that specific β2 adrenoceptor blockade prevents the hypotensive episodes. Methods We used a radiotransmitter to record SGNA, VNA and blood pressure (BP) in 8 ambulatory dogs. Video imaging was used to document postural changes. Results Out of these 8 dogs, 5 showed simultaneous sympathovagal discharges in which the minute by minute integrated SGNA correlated with integrated VNA in a linear pattern (“Group 1”). In these dogs abrupt termination of simultaneous SGNA-VNA at the time of postural changes (as documented by video imaging) was followed by abrupt (>20 mmHg over 4 beats) drops in BP. Dogs without simultaneous on/off firing (“Group 2”) did not have drastic drops in pressure. ICI 118,551 (ICI, a specific β2-blocker) infused at 3.1 µg/kg/hr for 7 days significantly increased BP from 126 (95% confidence interval, CI: 118 to 133) mmHg to 133 (95% CI 125 to141) mmHg (p=0.0001). The duration of hypotension (mean systolic BP < 100 mmHg) during baseline accounted for 7.1% of the recording. The percentage was reduced by ICI to 1.3% (p = 0.01). Conclusions Abrupt simultaneous termination of SGNA-VNA was observed at the time of orthostatic hypotension in ambulatory dogs. Selective β2 adrenoceptor blockade increased BP and reduced the duration of hypotension in this model

Apamin-Sensitive Calcium-Activated Potassium Currents in Rabbit Ventricles with Chronic Myocardial Infarction

Introduction Apamin-sensitive small-conductance calcium-activated potassium current (IKAS) is increased in heart failure. It is unknown if myocardial infarction (MI) is also associated with an increase of IKAS. Methods and Results We performed Langendorff perfusion and optical mapping in 6 normal hearts and 10 hearts with chronic (5 weeks) MI. An additional 6 normal and 10 MI hearts were used for patch clamp studies. The infarct size was 25% [95% confidence interval, 20 to 31] and the left ventricular ejection fraction was 0.5 [0.46 to 0.54]. The rabbits did not have symptoms of heart failure. The action potential duration measured to 80% repolarization (APD80) in the peri-infarct zone (PZ) was150 [142 to 159] ms, significantly (p=0.01) shorter than in the normal ventricles (158 to 177] ms). The intracellular Ca transient duration was also shorter in the PZ (148 [139 to 157] ms) than in normal ventricles (168 [157 to 180] ms; P=0.017). Apamin prolonged the APD80 in PZ by 9.8 [5.5 to 14.1] %, which is greater than in normal ventricles (2.8 [1.3 to 4.3] %, p=0.006). Significant shortening of APD80 was observed at the cessation of rapid pacing in MI but not in normal ventricles. Apamin prevented postpacing APD80 shortening. Patch clamp studies showed that IKAS was significantly higher in the PZ cells (2.51 [1.55 to 3.47] pA/pF, N=17) than in the normal cells (1.08 [0.36 to 1.80] pA/pF, N=15, p=0.019). Conclusion We conclude that IKAS is increased in MI ventricles and contributes significantly to ventricular repolarization especially during tachycardia

Cervical vagal nerve stimulation activates the stellate ganglion in ambulatory dogs

BACKGROUND AND OBJECTIVES: Recent studies showed that, in addition to parasympathetic nerves, cervical vagal nerves contained significant sympathetic nerves. We hypothesized that cervical vagal nerve stimulation (VNS) may capture the sympathetic nerves within the vagal nerve and activate the stellate ganglion. MATERIALS AND METHODS: We recorded left stellate ganglion nerve activity (SGNA), left thoracic vagal nerve activity (VNA), and subcutaneous electrocardiogram in seven dogs during left cervical VNS with 30 seconds on-time and 30 seconds off time. We then compared the SGNA between VNS on and off times. RESULTS: Cervical VNS at moderate (0.75 mA) output induced large SGNA, elevated heart rate (HR), and reduced HR variability, suggesting sympathetic activation. Further increase of the VNS output to >1.5 mA increased SGNA but did not significantly increase the HR, suggesting simultaneous sympathetic and parasympathetic activation. The differences of integrated SGNA and integrated VNA between VNS on and off times (ΔSGNA) increased progressively from 5.2 mV-s {95% confidence interval (CI): 1.25-9.06, p=0.018, n=7} at 1.0 mA to 13.7 mV-s (CI: 5.97-21.43, p=0.005, n=7) at 1.5 mA. The difference in HR (ΔHR, bpm) between on and off times was 5.8 bpm (CI: 0.28-11.29, p=0.042, n=7) at 1.0 mA and 5.3 bpm (CI 1.92 to 12.61, p=0.122, n=7) at 1.5 mA. CONCLUSION: Intermittent cervical VNS may selectively capture the sympathetic components of the vagal nerve and excite the stellate ganglion at moderate output. Increasing the output may result in simultaneously sympathetic and parasympathetic capture

Nanostring-based multigene assay to predict recurrence for gastric cancer patients after surgery

10.1371/journal.pone.0090133PLoS ONE93-POLN

Long-term temporal changes of macular thickness and visual outcome after vitrectomy for idiopathic epiretinal membrane

Jongshin Kim, Kyoung Min Rhee, Se Joon Woo, Young Suk Yu, Hum Chung and Kyu Hyung Par

Ginsenoside Rg3-enriched red ginseng extract inhibits platelet activation and in vivo thrombus formation

Background: Korean Red Ginseng has been used for several decades to treat many diseases, enhancing both immunity and physical strength. Previous studies have documented the therapeutic effects of ginseng, including its anticancer, antiaging, and anti-inflammatory activities. These activities are mediated by ginsenosides present in the ginseng plant. Ginsenoside Rg3, an effective compound from red ginseng, has been shown to have antiplatelet activity in addition to its anticancer and anti-inflammatory activities. Platelets are important for both primary hemostasis and the repair of the vessels after injury; however, they also play a crucial role in the development of acute coronary diseases. We prepared ginsenoside Rg3-enriched red ginseng extract (Rg3-RGE) to examine its role in platelet physiology. Methods: To examine the effect of Rg3-RGE on platelet activation in vitro, platelet aggregation, granule secretion, intracellular calcium ([Ca2+]i) mobilization, flow cytometry, and immunoblot analysis were carried out using rat platelets. To examine the effect of Rg3-RGE on platelet activation in vivo, a collagen plus epinephrine-induced acute pulmonary thromboembolism mouse model was used. Results: We found that Rg3-RGE significantly inhibited collagen-induced platelet aggregation and [Ca2+]i mobilization in a dose-dependent manner in addition to reducing ATP release from collagen-stimulated platelets. Furthermore, using immunoblot analysis, we found that Rg3-RGE markedly suppressed mitogen-activated protein kinase phosphorylation (i.e., extracellular stimuli-responsive kinase, Jun N-terminal kinase, p38) as well as the PI3K (phosphatidylinositol 3 kinase)/Akt pathway. Moreover, Rg3-RGE effectively reduced collagen plus epinephrine-induced mortality in mice. Conclusion: These data suggest that ginsenoside Rg3-RGE could be potentially be used as an antiplatelet therapeutic agent against platelet-mediated cardiovascular disorders