Tehran University Medical Journal

Herbal essential oils are volatile, natural, complex compounds formed by medicinal plants as secondary metabolites. As reported by international organization for standardization (ISO), the term "essential oils" (EOs) is defined for a product obtained from vegetable raw materials or fruit using distillation with water or steam. The EOs are generally complex mixtures of volatile organic compounds include hydrocarbons (terpenes and sesquiterpenes) and oxygenated compounds (alcohols, esters, ethers, aldehydes, ketones, lactones, phenols, and phenol ethers) compounds. In medicinal plants, the EOs chemical profile usually very varies because of both intrinsic (sexual, seasonal, ontogenetic, and genetic variations) and extrinsic (ecological and environmental aspects) factors, also the EOs composition differs not only in the number and type of molecules but also in their stereochemical structures, and can be very different according to the extraction method. EOs represents a “green” alternative in the nutritional and pharmaceutical fields due to reported antimicrobial, antioxidant, anti-inflammatory and anticancer properties thus, in recent times; EOs has gained great popularity as consumers have developed a particular ever-growing awareness toward the use of natural ingredients, especially in food and household. Therefore, the present review provides a comprehensive summary on the method of preparation of EOs from medicinal plants, chemical composition analysis, their biological and pharmacological effects and their potential benefits on health level. Present information was compiled using keywords “Essential oil, Medicinal Plants and Natural additive in scientific database as Science Direct, Elsevier, PubMed, Google scholar and SID, until 2005 to 2015. EOs have great antimicrobial activity and mostly destroy bacteria, fungi and viruses without harmful effects on consumer’s health. Finding of this study showed that the Thymol, α-Pinene, β-Pinene, Cumin Aldehyde, Carvacrol, Germacrene, Linalool were the main components. Also, EOs have antioxidant, anti-inflammatory and many other pharmacological properties which enhance their potential application. EOs have potential biological and pharmacological activities and so have many applications in pharmaceutical and food industries.

Sudden cardiac death in sport, although rare, but is a tragic event, attracting the media and public attention. Sport and exercise may act as a trigger for sudden cardiac death. Risk of sudden death in young athletes with cardiovascular disease is 2.5 times more frequent than non-athlete individuals. More than 90% of cases of sudden death occur during or immediately after training or competition. Incidence of sudden cardiac death in any population, including athletes, is related to multiple factors such as gender, age, race, nationality, diagnostic screening methods and preventive measures for sudden cardiac death. Otherwise, incidence rate of sudden cardiac death is linked to the used definition and method of diagnosis. Different cardiovascular disorders may result in death of young athletes and hypertrophic cardiomyopathy, congenital coronary anomalies, arrhythmogenic right ventricular dysplasia and aortic rupture are among the most common causes. Marfan syndrome, dilated cardiomyopathy, viral myocarditis, Wolff-Parkinson-White (WPW) syndrome, congenital long QT syndrome, Brugada syndrome and commotio cordis are reported as other etiologies. In older athletes (more than 35 years), ischemic coronary heart disease is responsible for majority of the cases similar to the general population. Because the outcome of sudden cardiac arrest in sports is very poor except in few cases, proper national strategies are needed to diminish the burden of sudden death in young athletes. It seems that there are two main strategies to achieve this goal: A) Primary prevention with use of purposeful pre-participation evaluation programs. This evaluation should focuss on the proper history and physical examination. Nevertheless, there is significant debate between American and European countries regarding the use of paraclinical investigations (especially ECG). American heart association does not recommend ECG as an essential part of evaluation. In contrast, European society of cardiology and international olympic committee advocate ECG for all athletes younger than 35 years. However, all evaluations should be based on national, generally accepted standards and done by well-educated experts. B) Setting evidence-based and updated protocols for early and effective cardiopulmonary resuscitation (CPR), attendance of well equipped medical staff and early access to automated external defibrillator (AED) in all sport events and implementing CPR education in all coaching training courses.

Background: Total body irradiation (TBI) is a technique that is commonly used as a part of the patient conditioning regimen before the bone marrow transplant (BMT). The purpose of this study is to introduce and implement a reasonable TBI technique on the human-like phantom in Imam Khomeini Hospital in Tehran.
Methods: The present experimental study was conducted from October 2016 to November 2017 to implement the TBI technique at the Cancer Institute of Imam Khomeini Hospital in Tehran. For this purpose, percentage depth dose, and dose rate were measured in TBI condition (i.e. SSD=310 cm, field size=40×40 cm2, gantry angle=90°, and collimator angle 45°) in homogeneous phantom. Gafchromic EBT3 films were used to measure the absorbed dose in different areas of the human like phantom at the levels of head, neck, thyroid, lung, umbilicus, pelvic, thigh, knee and leg. Phantom irradiation was performed in parallel opposed anterior-posterior geometry using an 18MV photon beam produced by Varian 2100C/D. Cerrobend blocks were used for lung protection. After analyzing the exposed films with Image J software, the dose uniformity was calculated.

Conclusion: The implemented technique, obtained the acceptable ±10% dose uniformity in most of the body regions. The dosing accuracy was within the acceptable range. The lungs¢ dose was reduced to the desired level using lung shields. This technique is a simple and cost-effective method that does not require complicated dosimetric techniques. Regarding the obtained results, the proposed technique has the necessary conditions for implementation in Imam Khomeini hospital in Tehran.