Mechanisms of phytoestrogen biochanin A-induced vasorelaxation in renovascular hypertensive rats

BACKGROUND: The plant-derived estrogen biochanin A is known to cause vasodilation, but its mechanism of action in hypertension remains unclear. This study was undertaken to investigate the effects and mechanisms of biochanin A on the thoracic aorta in two-kidney, one clip (2K1C) renovascular hypertensive rats. METHODS: Hypertension was induced by clipping the left renal artery, and control age-matched rats were sham treated. Thoracic aortae were mounted in tissue baths to measure isometric tension. RESULTS: Biochanin A caused concentration-dependent relaxation in aortic rings from 2K1C hypertensive and sham-treated rats, which was greater in 2K1C rats than in sham rats. Biochanin A-induced relaxation was significantly attenuated by removing the endothelium in aortic rings from 2K1C rats, but not in sham rats. Nomega-Nitro-L-arginine methylester, a nitric oxide synthase inhibitor, or indomethacin, a cyclooxygenase inhibitor, did not affect the biochanin A-induced relaxation in aortic rings from 2K1C and sham rats. By contrast, treatment with glibenclamide, a selective inhibitor of adenosine triphosphate-sensitive K+ channels, ortetraethy-lammonium, an inhibitor of Ca2+-activated K+ channels, significantly reduced biochanin A-induced relaxation in aortic rings from both groups. However, 4-aminopyridine, a selective inhibitor of voltage-dependent K+ channels, inhibited the relaxation induced by biochanin A in 2K1C rats, whereas no significant differences were observed in sham rats. CONCLUSION: These results suggest that the enhanced relaxation caused by biochanin A in aortic rings from hypertensive rats is endothelium dependent. Vascular smooth muscle K+ channels may be involved in biochanin A-induced relaxation in aortae from hypertensive and normotensive rats. In addition, an endothelium-derived activation of voltage-dependent K+ channels contributes, at least in part, to the relaxant effect of biochanin A in renovascular hypertension.

Experience of a Medical Assistance for Disaster Caused by a Typhoon of Haiyan in the Philippines

PURPOSE: On November 8, 2013, Typhoon Haiyan attacked the Philippines, causing damage to many houses and trees as well as loss of many lives. A medical team from our hospital and university was sent to Philippines in order to provide medical assistance. We wish to describe our experiences of disaster medicine and discuss problems and improvement points. METHODS: We analyzed the characteristics of patients who received medical treatment administered by us at Tagobon city in the Philippines for five days. RESULTS: We provided medical services to 951 patients for five days. Most patients visited us for medical treatment not trauma. Almost all chief complaints were associated with respiratory, gastrointestinal, dermatologic, and ophthalmologic symptoms. We mainly treated the patients with medications. CONCLUSION: During the subacute period after the disaster, most patients complained of medical and dermatologic problems due to lack of sanitation rather than traumatic complications. Medical assistance for disaster should be administered appropriately according to the types of diseases that occurduring each period after disaster.

Diagnostic Accuracy of Bone Scan Compared to Computed Tomography of Thorax Fractures of Chest Trauma Patients

PURPOSE: Thorax computed tomography (CT) is the diagnostic test for chest trauma patients in the emergency department. Thorax CT has high diagnostic accuracy for rib, sternum fractures. However, rib, sternum fractures are often missed by thorax CT. In this study, the accuracy of thorax CT as a diagnostic test of rib, sternum fractures was examined by comparing the diagnosis of rib, sternum fractures by bone scan. METHODS: A total of 112 patients who had visited the emergency department due to chest trauma and who had undergone both thorax CT and bone scan from January 1, 2010, to June, 30, 2013 were examined. We examined the patients'characteristics, vital signs and cause of trauma through a retrospective analysis of medical records, and thorax CT and bone scan were read by a radiologist and a nuclear medicine specialist. RESULTS: Among 112 patients, 62 patients (55.3%) were male, 50 patients (44.7%) were female, and mean age was 56. There were 59 patients who had no fracture on thorax CT and were regarded as contusion. In 59 patients, 28 patients (47.5%) were diagnosis rib, sternum fractures detected by bone scan. Sex (p=0.188), age (p=0.624), and cause of trauma (p=0.389) were not significant predictors for rib, sternum fractures. However, combined fracture (p=0.043) showed significant correlation. In this study, the sensitivity, specificity, positive predictive value, and negative predictive value of thorax CT in diagnosis of rib, sternum fractures were 64.5%, 93.9%, 96.2%, and 52.5%. CONCLUSION: Thorax CT has low sensitivity (64.5%) and low negative predictive value (52.5%) in detection of rib, sternum fractures. Although thorax CT shows no thorax fracture, when patients have persistent pain or they need accurate diagnosis, we may recommend bone scan for detection of rib, sternum fractures and accurate diagnosis.

Validation of the Pentax-AWS Airwayscope as a Prehospital Intubation Device by Korean Level 1 Emergency Medical Technicians; A Simulation Study Using an Airway Training Manikin

PURPOSE: Tracheal intubation in the pre-hospital setting may be lifesaving in severely ill and injured patients. The aim of the current study was to evaluate whether use of the video laryngoscope, when used by Korean level 1 emergency medical technicians, resulted in faster or more secure facilitation of tracheal intubation, compared with the conventional laryngoscope with the immobilized cervical spine lying on the ground. METHODS: Thirty two level 1 EMTs working as 119 rescuers performed tracheal intubation on a manikin using the Macintosh laryngoscope (McL) and the Pentax-AWS(R) airwayscope (AWS) "on-the-bed" and "on-the-ground" in simulations with or without cervical spine immobilization. We compared intubation time, dental injury, and visual analog scale for both types of laryngoscope. RESULTS: In the McL trial, four participants failed on the bed, and 11 failed on the ground with cervical immobilization. In the AWS trial, all participants successfully secured the airway regardless of cervical spine immobilization both on the bed and on the ground. With the AWS, intubation time was not lengthened due to cervical spine immobilization either on the bed or on the ground. The AWS score was better than the McL on the visual analog scale in ease of handling the laryngoscope both on the bed and on the ground. And use of the AWS resulted in the lowest number of dental compressions. CONCLUSION: We conclude that the AWS is an effective and safe device for use in pre-hospital intubation with cervical spine immobilization, not only on the bed but also on the ground, when used by Korean level 1 EMTs. However, conduct of further studies is required in order to validate the clinical relevance of these findings.

Animal Experiments of Heart Transplantation for Complicated Congenital Heart Disease in Neonate / 대한흉부외과학회지

BACKGROUND: Heart transplantation is considerated for a selected certain group of complicated congenital heart disease in neonates because corrective surgery is very difficult and has high mortality. Precise planning of transplantation is necessary to adequately fit the donor heart to the recipient. MATERIAL AND METHOD: We have performed 4 neonatal pig heart transplantations to test the technical feasibility. Experiment 1: The transplantation was performed using the same technique as the adult heart transplantation. Experiment 2: The transplantation for hypoplastic left heart syndrome was simulated as we reconstructed the whole aortic arch with donor aorta. Experiment 3: The heart transplantation was done with radical pulmonary artery reconstruction. Experiment 4: The experiment was performed for a long term survival. RESULT: Preoperative planning was very important for adequate fitting. All animals could be weaned from cardiopulmonary bypass, however, two animals died due to bleeding at pulmonary artery and left atrium. CONCLUSION: We concluded that the neonatal heart transplantation can be applied in some complicated Further using animal model is mandatory.