Effects of dietary supplementation with cod-liver oil on endothelium-dependent responses in porcine coronary arteries

To study the effect of dietary supplemntation with fish oil on endothelium-dependent responses, Yorkshire pigs were maintained on a normal diet or on a low (0.6 ml/kg/day) or a high (1.0 ml/kg/day) dose of cod-liver oil for 4 weeks. Endothelium-dependent responses were examined in vitro in rings of proximal left anterior descending coronary arteries taken from control and treated animals studied in parallel. Endothelium-dependent relaxations in response to bradykinin, serotonin, adenosine diphosphate, and thrombin were facilitated in arteries from treated but not in those from control animals, whereas the relaxations in response to A23187 were unaltered. The facilitated relaxations were not altered by indomethacin but significantly inhibited by methylene blue. Aggregating platelets from control and treated pigs induced comparable, facilitated endothelium-dependent relaxations in rings taken from treated pigs. The platelet-induced contractions were significantly reduced in rings with endothelium taken from treated pigs, and they were comparable in rings without endothelium in both groups. Aggregating platelets from control and treated pigs released comparable amounts of serotonin and thromboxane A2. Endothelium-dependent relaxations induced by arachidonic acid and eicosapentaenoic acid were unaltered, whereas transient endothelium-dependent contractions induced by arachidonic acid were significantly reduced by the treatment with cod-liver oil. Relaxations to sodium nitroprusside or isoproterenol, and contractions to potassium chloride or serotonin were not different in rings without endothelium from control or treated pigs. These results indicate that dietary supplementation with cod-liver oil facilitates endothelium-dependent relaxations and inhibits endothelium-dependent contractions in porcine coronary arteries.link_to_subscribed_fulltex

Evaluating the efficacy of electrical vestibular stimulation (VeNS) on insomnia adults : study protocol of a double-blinded, randomized, sham-controlled trial

202403 bcvcVersion of RecordOthersNeurovalens (UK)PublishedC

The effectiveness of electrical vestibular stimulation (VeNS) on symptoms of anxiety : study protocol of a randomized, double-blinded, sham-controlled trial

202403 bcvcVersion of RecordOthersNeurovalens (UK)PublishedC

Effects of Transcranial Pulse Stimulation (TPS) on adults with symptoms of depression - a pilot randomized controlled trial

202403 bcvcVersion of RecordRGCOthersHong Kong Polytechnic University; Roland Beisteiner received research grants and laboratory support from the Medical University of Vienna and University of Vienna; Austrian Science Fund; STORZ Medical AG and Herzfelder’sche FamilienstiftungPublishedC

Porcine liver: Morphologic characteristics and cell viability at experimental radiofrequency ablation with internally cooled electrodes

PURPOSE: To evaluate morphologic characteristics and cell viability of radiofrequency ablation zones in porcine liver. MATERIALS AND METHODS: Approval of the study protocol was obtained from the Ethics Committee on Use of Live Animals for Teaching and Research at University of Hong Kong. Internally cooled electrodes were used to produce 120 ablated zones ex vivo and 60 ablated zones in vivo with single electrodes (1-, 2-, and 3-cm exposed lengths) or clustered electrodes (1.0-, 2.0-, and 2.5-cm exposed lengths) at 4, 8, 12, and 16 minutes of ablation (ex vivo) and 8 and 12 minutes of ablation (in vivo). Morphologic measurements of each ablated zone were performed. Cell viability in each ablated zone was assessed qualitatively with histochemical staining and quantitatively with measurement of intracellular adenosine 5′-triphosphate (ATP) concentration. RESULTS: Exposed length of electrode (coefficient = 0.79, standard error = 0.04, P < .001), duration of ablation (coefficient = 0.14, standard error = 0.01, P < .001), and clustered electrode design (coefficient = 1.21, standard error = 0.05, P < .001) were independent factors that affected minimal transverse diameter and volume of ablated zone in ex vivo study. Similar morphologic characteristics existed among ablated zones in in vivo study. Mean distance of ablation beyond the electrode tip remained constant (ex vivo, 1.0 cm ± 0.08 [standard deviation]; in vivo, 0.5 cm ± 0.05) regardless of different ablation conditions. Histochemical staining revealed no viable hepatocytes from center to margins of white zone in each ablated area. Mean intracellular ATP concentration in margins of white zone (9.5 × 10-12 mol/μg DNA ± 1.43) was lower than that in red zone (4088 × 10-12 mol/μg DNA ± 65.97, P < .001) and in adjacent normal liver (4528 × 10-12 mol/μg DNA ± 52.74, P < .001). CONCLUSION: Distance of ablation beyond the tip of the electrode remained constant (ex vivo, 1.0 cm; in vivo, 0.5 cm) with different conditions of ablation. Complete and uniform cellular destruction was achieved in the white zone of ablated area. © RSNA, 2005.link_to_subscribed_fulltex