Browsing by Subject "Smoking"

Now showing 1 - 4 of 4

Open Access
The effect of Maras powder and smoking on the microRNA deregulation of oral mucosa
(Faculdade De Odontologia De Bauru - USP, 2020) Taş, B.; Güre, Ali Osmay
Objective: This study aimed to investigate the effects of Maras powder (a type of smokeless tobacco obtained from Nicotiana rustica Linn and mixed with the ashes of wood, especially from oak, walnut or grapevine) on the microRNA (miRNA) deregulation of oral mucosa, and it compares these effects with those of smoking. Methodology: Oral mucosal samples were collected from 74 patients, consisting of 16 nonusers, 26 smokers, and 32 Maras powder users. Genes associated with oral cancer were selected and 90 microRNAs targeting these genes were identified. MicroRNA were isolated and purified using the microRNA isolation kit. MicroRNA were expressed using Fluidigm RT-PCR. Results: A positive correlation between the duration of Maras powder use with miR-31 expression levels, and a negative correlation between the Maras powder chewing time and miR-372 expression levels was found. In addition, there is a negative correlation between the amount of Maras powder consumed and expression levels of miR-375, miR-378a, miR-145, and miR-10b; moreover, another negative correlation is observed between the number of cigarettes consumed and the expression levels of miR-23a, miR-23b, miR-203a, miR-200b, and miR-375. However, miR-200b and miR-92a levels were downregulated significantly more in Maras powder users when compared with smokers and nonusers (p<0.05). Conclusion: The results show both chewing Maras powder and smoking have an effect on deregulation of miR-200b and miR-92a expressions. This leads to the belief that assessing the expression of these two miRNAs is a promising noninvasive method of analysis, especially in mutagen exposures. Finally, large-scale and high-throughput studies may help to identify an extensive miRNA expression profile associated with tobacco use and improve the understanding of oral malignancies.
Open Access
Ischemic stroke phenotype in patients with nonsustained atrial fibrillation
(Lippincott Williams and Wilkins, 2015) Arsava, E. M.; Bas, D. F.; Atalar, Ergin; Has, A. C.; Oguz, K. K.; Topcuoglu, M. A.
Background and Purpose: The widespread use of ambulatory cardiac monitoring has not only increased the detection of high-risk arrhythmias like persistent and paroxysmal atrial fibrillation (AF), but also made it possible to identify other aberrations such as short-lasting (<30 seconds) irregular runs of supraventricular tachycardia. Ischemic stroke phenotype might be helpful in understanding whether these nonsustained episodes play a similar role in stroke pathophysiology like their persistent and paroxysmal counterparts. Methods: In a consecutive series of patients with ischemic stroke, we retrospectively determined clinical and imaging features associated with nonsustained AF (n=126), defined as <30-second-lasting supraventricular tachyarrhythmias with irregular RR interval on 24-hour Holter monitoring, and compared them to patients with persistent/paroxysmal AF (n=239) and no AF (n=246). Results: Patients with persistent/paroxysmal AF significantly differed from patients with nonsustained AF by a higher prevalence of female sex (odds ratio [95% confidence interval], 1.8 [1.1-2.9]), coronary artery disease (1.9 [1.1-3.0]), and embolic imaging features (2.7 [1.1-6.5]), and lower frequency of smoking (0.4 [0.2-0.8]) and hyperlipidemia (0.5 [0.3-0.8]). In contrast, patients with no AF were younger (0.5 [0.4-0.6] per decade) and more likely to be male (1.7 [1.0-2.8]) in comparison with nonsustained AF population. The prevalence of nonsustained AF was similar among cryptogenic and noncryptogenic stroke patients (32% versus 29%). Voxel-wise comparison of lesion probability maps revealed no significant difference between cryptogenic stroke patients with and without nonsustained AF. Conclusions: Clinical features of patients with nonsustained AF exhibited an intermediary phenotype in between patients with persistent/paroxysmal AF and no AF. Furthermore, imaging features did not entirely resemble patterns observed in patients with longer durations of AF.
Open Access
Smoking and nicotine alter UGT1A expression
(2011) Ölmezer, Gizem
The expression and activity of enzymes taking role in drug metabolism are important as in the case of phase II glucuronidation enzymes; namely UDPglucuronosyltransferases (UGTs). Previously, it has been identified that smoking upregulates the expression of UGT enzymes in oral mucosa. We asked whether smoking induces UGT1A expression in other tissues and re-analyzed publically available datasets run with samples from smokers and non-smokers. It was observed that UGT1A enzymes were overexpressed in several types of epithelial cells of smokers. 30% of nicotine metabolism is performed by UGT enzymes; however, whether UGT1A expression is modulated by nicotine, the addictive component of tobacco smoke, is not known. For this purpose, the expression levels of UGT1A isoforms were measured using Real-Time PCR in nicotine treated SW620 colorectal cancer cells. Our findings showed that nicotine’s effect on UGT1A expression was isoform specific; and the magnitude of modulation differed among isoforms. Furthermore, the upregulation of UGT1A enzymes could only be observed in serum-deprived SW620 cells. In summary, nicotine metabolism enzymes are regulated by both smoking in vivo and nicotine in vitro. Nevertheless, enhanced xenobiotic metabolism may result in chemoresistance, which is undesirable for cancer patients. Therefore, before drug therapy cancer patients might be analyzed in terms of their smoking status and UGT1A expression patterns.
Open Access
The effects of smoking restrictions on class attendance and life satisfaction: evidence from a Turkish University
(2024-06) Kılınç, Sena
We investigate the effect of smoking regulations on a university campus regarding attendance frequency, life satisfaction, and campus satisfaction among university students. A private university in Turkey implemented a campus-wide smoke-free policy, which prohibited smoking on campus except in designated areas at least 150 meters from faculty buildings. In our theoretical framework, we analyze a simple game for smoker and nonsmoker students with different types. In order to analyze the testable implications, we conducted an online survey with retrospective questions to third and fourth-year students. 406 students responded to our survey. In the empirical methodology, we model attendance frequency as a function of various factors, including individual fixed effects driven by intrinsic motivation for attendance, faculty fixed effects affected by faculty-related attendance policies, a time effect that may impact attendance trends, and a heterogeneous policy effect based on time and distance to smoking areas. As an alternative approach to the first one, instead of modelling individual fixed effects and adjusting for them through first differencing, we employ a difference-in-differences model. Our findings indicate that attendance increased and the smoking intensity among students decreased after the implementation of the policy for smoker students. Remarkably, the results obtained through the alternative approach align with those of the primary methodology. Also, the findings are consistent with the theoretical framework. JEL Classification: I1, I23, I28, I31.