فصلنامه نفس
سال یکم شماره 2 (تابستان 1393)

Biological macromolecules, including DNA, RNA, and proteins, have intrinsic features that make them potential building blocks for the fabrication of nanodevices. Peptides and proteins have been studied for applications in nanotechnology extendedly and the field of DNA nanotechnology is now well established. The concept of RNA nanotechnology has been around for more than a decade, and the first evidence for the construction of RNA nanoparticles through the self-assembly of several re-engineered natural RNA molecules reported in 1998. Since RNA molecules can be designed and manipulated with both a level of simplicity characteristic of DNA and a versatile flexibility in structure and function (including enzymatic activities) similar to that of proteins, there became an interesting candidate for nanotechnological applications. Two and three dimensional structure of RNA nanoparticles can be fabricated by self-assembled interactions of special RNA molecules. The best characterized RNA multiplier and the first to be described in the RNA nanotechnological application is the motor pRNA of bacteriophage phi29 which form dimers, trimers, and hexamers. Both ribozyme or therapeutic siRNA and a receptor binding RNA aptamer have been engineered into individual RNA nanoparticles. The most important disease that needs the help of RNA nanotechnology to improve the degree of malignancy is lung cancer. Lung cancer is one of the widespread cancers all over the word and the patients often died after 5 years of challenging with this disease. Among all siRNAs applied for lung cancer therapy KRAS and P53 siRNAs are most important one on. This review covers the basic concepts of RNA nanoparticles structure and their role in lung cancer therapy.

Tuberculosis epidemiology is valuable for control of TB by understanding the transmission dynamics. A potential molecular epidemiology method to distinguish the origins of Mycobacterium tuberculosis is region of differences (RDs) polymorphisms. Worldwide, 68 RDs have been specified, so far. By studying deletion and polymorphisms in the RD regions of RD1, RD150 and RD181, this study focused on the molecular diversity of Mycobacterium tuberculosis in Iran for the first time. One hundred ninety Mycobacterium tuberculosis strains were isolated from patient’s clinical samples in Mycobacteriology Research Center (MRC). DNA was extracted and spoligotyping was performed by using DR region PCR. The spoligotyping patterns were obtained from SPOLDB4 database. Drug susceptibility tests were performed for all isolates and finally, three regions of RD1, RD150 and RD181 loci were amplified by PCR. Out of 190 M. Tuberculosis strains, 70% of isolates were susceptible to Isoniazid, Rifampin and Etambutol drugs and the remaining (30%) were drug resistant. The spoligotyping patterns demonstrated H4 (127) and CAS families were more prevalent than other families by 37.5% and 20% respectively. Other prevalent families were T1 (9.5%), Beijing (11%) and unknown families (27%). The RD181 loci had deletion in Beijing strains, and RD1 showed deletion in BCG strains. The RD150 loci showed deletion in none of the strains. The RD1 and RD181 are appropriate to identify BCG and Beijing strains respectively. Whereas, RD150 loci is not efficient to show polymorphisms in various strains. As a result RD1 and RD181 polymorphism detection can be used effectively for molecular epidemiology studies to determine ongoing transmission clusters.

Substance abuse is among the biggest cultural, social and health dilemmas in the current world. Control and reduction of factors that enhance substance abuse may be helpful in this respect. This study evaluated the effect of tobacco smoking on the tendency to substance abuse.In this cross-sectional study, 1,372 records of clients presenting for substance abuse treatment were evaluated in terms of tobacco smoking status and other related factors. Data were statistically analyzed.A total of 1,306 males (95.2%) and 66 (4.8%) females were evaluated. More than 90% of participants were tobacco smokers. The highest frequency of smoking initiation was in the age group of 16-20 yrs. The mean age of smoking onset was 19.2±5.6 years with a mode of 18 years. Meanwhile, the mean age of substance abuse onset was 21.3± 7.1 years with a mode of 20 years. A significant association between the initiation age of smoking and substance abuse onset were found.Tobacco smoking can be a predisposing factor for substance abuse. This association necessitates the precise implementation of tobacco control policies and preventive measures and emphasizes on smoking cessation at early ages.

People’s attitude towards combating air pollution is an important determining factor in creating an appropriate base for providing educational programs about air pollution reduction. This study examines school student's attitudes towards ways of combating air pollution in order to assist authorities in educational planning.In this cross-sectional study, a closed-form questionnaire was used to evaluate 2140 guidance and high school student's attitude towards ways of air pollution reduction, their idea about their own knowledge on this subject and also their risk perception about air pollution. Some statistic tests such as Chi Square, Mann-Whitney, Kruskal-Wallis were used to analyze data. The sampling method was multi stage.While the range of student’s ‘affective score’ varied from -12 to +12, student's mean affective score was equal to +5.76 (SD 3.79). Affective Score was significantly different between girls and boys (5.43 vs. 5.94 respectively). Among the suggested ways of combating air pollution, they agreed with "Me and my friends should be taught more about air pollution" more than other ways.The students worried so much about air pollution and they had appropriate risk perception about it, however, it seems the actions that have been done in this regard were not acceptable by them. Hence, it is essential to respond to their high motivation by more comprehensive planning and precise administrative methods.

MicroRNAs play pivotal role in tumorigenesis, including lung tumors. Mutations of TrkC gene are also related to lung cancers. Recently, we have discovered a novel miRNA named TrKC-miR1 (has-miR11181), located in the human TrKC gene (EBI acc # HG969187). Here, we intended to investigate TrKC-miR1 expression status in pairs of lung tumors and their marginal tissues.Total RNAs from 11 lung tumors and their marginal tissue samples were extracted. Then, real-time PCR was performed to analyze TrkC-miR1 expression, following cDNA synthesis.Data analysis revealed that TrkC-miR1 expression was elevated in squamous cell carcinoma related to marginal tumor tissues. However, TrkC-miR1 expression was decreased in large cell carcinoma and adenocarcinoma, compared to the marginal tumor tissues.Results of current study shows that TrkC-miR1 has a distinct expression pattern in different histopathological types of lung tumor. It remains to be tested in more tumor samples, if TrkC-miR1could be used as a tumor marker for distinction of lung tumor subtypes.

There is no study about fractal variability of breathing pattern in patients with respiratory diseases, such as asthma. The aim of this study was evaluating fractal variability of breathing pattern in healthy and asthmatic cases. Forty men, including 10 healthy volunteers, 10 patients with controlled atopic asthma (CAA), 10 patients with uncontrolled atopic asthma (UAA), and 10 patients with uncontrolled non-atopic asthma (UNAA) referred to the outpatient clinic of Dr. Masih Daneshvari Hospital (Tehran, Iran) were enrolled in this study. The thoraco-abdominal movements were collected using two respiratory belts and then signals were calibrated to respiratory volume. We analyzed the fractal variability of inter breath interval (IBI) and volume fluctuation using detrended fluctuation analysis (DFA). The α index values in healthy, CAA, UAA, and UNAA cases with respect to IBI were 0.82±0.03, 0.73±0.06, 0.68±0.04, and 0.57±0.04, respectively, and with respect to volume fluctuation were 0.83±0.10, 0.75±0.06, 0.70±0.05, and 0.59±0.04, respectively. There were significant differences between all groups in α index values of both IBI and volume fluctuation (p<0.05). We concluded that the fractal correlation of breathing pattern in asthmatic patients is lower than healthy cases. This difference increased in uncontrolled asthma.

The importance of organ donation is increasing world wild. The knowledge and attitude of the medical staffs, including nurses, and their positive motivation in this regard are considered as the advantage to achieve a better transplantation results. This study aimed to investigate nurses’ attitude, awareness and performance about organ transportation in Dr. Masih Daneshvari Hospital. The present study evaluated the opinions of 66 randomly selected, educated nurses who had at least one year experience in different wards of the hospital. Using a Farsi questionnaire, nurses’ attitudes, knowledge and practice data on organ transplantation, as well as their demographic information were surveyed. The validity and reliability of the questionnaire were determined by means of content validity and test-retest (r=0.81) methods, respectively. Using SPSS 16, data analysis was done, hence, descriptive (i.e. absolute and relative frequency tables, mean and standard deviation) and analytical (e.g. Chi2, t-test) statistical results were obtained. The range of age of the majority of participants was 20-40 years old (74.2% woman and 25.8% man). The results showed a significant inverse relationship between the age and the psycho-emotional status of the nurses, regarding the care of brain death patients. The participants’ point of view on the organ transplantation was 12.3% opposite, 17.6% surely agree, 54.7% agree only when there is condition improvement, and 15.4% indifferent.The results also showed that a high percentage of nurses have lack of enough knowledge on organ transplantation. As the educational course and subsequent awareness can be highly effective on their attitude, therefore, the increase of awareness, together with condition improvement, could be important to enhance the care of transplant patients.

In patients with myasthenia gravis, anesthesia for tracheal resection and reconstruction surgery is a serious challenge; due to post-surgical considerable risk for mechanical ventilatory support. Postoperative positive pressure ventilation and an endotracheal cuff pressure may cause anastomosis dehiscence after surgery.In this case report, we discuss the usage of a non-relaxant, total intravenous anesthesia technique to decrease the risk of post-surgical ventilatory support, in a case of tracheal resection surgery of a myasthenia gravis patient with post intubation subglottic stenosis.