230 research outputs found
Twist/Writhe Partitioning in a Coarse-Grained DNA Minicircle Model
Here we present a systematic study of supercoil formation in DNA minicircles
under varying linking number by using molecular dynamics simulations of a
two-bead coarse-grained model. Our model is designed with the purpose of
simulating long chains without sacrificing the characteristic structural
properties of the DNA molecule, such as its helicity, backbone directionality
and the presence of major and minor grooves. The model parameters are extracted
directly from full-atomistic simulations of DNA oligomers via Boltzmann
inversion, therefore our results can be interpreted as an extrapolation of
those simulations to presently inaccessible chain lengths and simulation times.
Using this model, we measure the twist/writhe partitioning in DNA minicircles,
in particular its dependence on the chain length and excess linking number. We
observe an asymmetric supercoiling transition consistent with experiments. Our
results suggest that the fraction of the linking number absorbed as twist and
writhe is nontrivially dependent on chain length and excess linking number.
Beyond the supercoiling transition, chains of the order of one persistence
length carry equal amounts of twist and writhe. For longer chains, an
increasing fraction of the linking number is absorbed by the writhe.Comment: 21 pages, 7 figures, 1 tabl
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Measurement, prevalence, and psychological risk factors associated with addictive food consumption: development of a new food addiction scale and evidence from a national largescale sample
Background and aims: To date, a number of studies have investigated the prevalence and correlates of addictive food consumption. However, these studies have mostly relied on models that comprised a narrow range of variables in often small and heterogenous samples. The purpose of the present study was to comprehensively examine the measurement aspects, the prevalence, and the psychological correlates of addictive eating among a largescale national sample of Turkish adults.
Method: Participants (N = 24,380, 50% men, M age = 31.79 years, age range = 18–81 years) completed a battery of tests including the Food Addiction Risk Questionnaire (FARQ), the Brief Symptom Inventory, the Toronto Alexithymia Scale, the Positive and Negative Affect Schedule, and the Experiences in Close Relationships-Revised.
Results: According to analyses conducted, the FARQ had a uni-dimensional factor structure. Based on Item Response Theory (IRT) calculated cut-off scores, 2.3% of the participants were at risk of addictive eating patterns, whilst criteria varied in their discriminating ability. The correlates of addictive food consumption were being male, being younger, having lower education, presenting with higher alcohol use, psychiatric symptoms, alexithymia, positive/negative affect, and anxious attachment.
Conclusion: These results suggest that a minority of Turkish community are at risk for addictive food consumption and that adverse psychological states promote this problematic behavior
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Measurement, profiles, prevalence, and psychological risk factors of problematic gaming among the Turkish community: a large-scale national study
The present study investigated the prevalence, the potential different profiles, and the associated psychological factors of disordered gaming using data from a large-scale epidemiological study (TURBAHAR [Turkey’s Addiction and Mental Health Risk Profile Map Project]) carried out in Turkey in 2018 with 24,494 participants aged 18–81 years. Participants completed a comprehensive survey comprising a demographic questionnaire, Gaming Addiction Risk Questionnaire, Brief Symptom Inventory, Personal Well-Being Index Adult Form, Positive and Negative Affect Schedule, Toronto Alexithymia Scale, and Experiences in Close Relationships-Revised Scale. Latent class analysis showed the existence of eight different game profiles, which differed in relation to the intensity and specific features of the behavior. Results showed that 1.6% of the participants were problematic gamers. Being male, being younger, lower education level, being single, using alcohol and cigarettes, psychiatric distress, positive and negative affect, and anxious adult attachment were positively associated with problematic gaming
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Sex addiction in Turkey: a large-scale survey with a national community sample
Prior studies on sex addiction have mostly relied on a narrow range of risk factors among small and heterogeneous samples. The purpose of the present study was to examine the psychological markers related to sex addiction in a large-scale community sample of Turkish adults. A total of 24,380 individuals completed a survey comprising the Sex Addiction Risk Questionnaire, the Brief Symptom Inventory, the Positive and Negative Affect Schedule, the Personal-Wellbeing Index Adult Form, the Toronto Alexithymia Scale, and the Experiences in Close Relationships-Revised (50% males; mean age = 31.79 years; age range = 18 to 81 years). Utilizing hierarchical regression analysis, sex addiction was associated with being male, being younger, having a lower education level, being single, being an alcohol and nicotine user, psychiatric distress, low personal wellbeing, positive and negative affect, alexithymia, and anxious attachment. This study suggests that socio-demographic factors and aforementioned detrimental psychological factors exacerbate higher engagement in addictive sexual behaviors among the Turkish community. However, more studies are needed to better understand the factors associated with sex addiction in Turkey
Diet and Anxiety: A Scoping Review.
Anxiety disorders are the most common group of mental disorders. There is mounting evidence demonstrating the importance of nutrition in the development and progression of mental disorders such as depression; however, less is known about the role of nutrition in anxiety disorders. This scoping review sought to systematically map the existing literature on anxiety disorders and nutrition in order to identify associations between dietary factors and anxiety symptoms or disorder prevalence as well as identify gaps and opportunities for further research. The review followed established methodological approaches for scoping reviews. Due to the large volume of results, an online program (Abstrackr) with artificial intelligence features was used. Studies reporting an association between a dietary constituent and anxiety symptoms or disorders were counted and presented in figures. A total of 55,914 unique results were identified. After a full-text review, 1541 articles met criteria for inclusion. Analysis revealed an association between less anxiety and more fruits and vegetables, omega-3 fatty acids, "healthy" dietary patterns, caloric restriction, breakfast consumption, ketogenic diet, broad-spectrum micronutrient supplementation, zinc, magnesium and selenium, probiotics, and a range of phytochemicals. Analysis revealed an association between higher levels of anxiety and high-fat diet, inadequate tryptophan and dietary protein, high intake of sugar and refined carbohydrates, and "unhealthy" dietary patterns. Results are limited by a large percentage of animal and observational studies. Only 10% of intervention studies involved participants with anxiety disorders, limiting the applicability of the findings. High quality intervention studies involving participants with anxiety disorders are warranted
Does Race Play a Role in Complications and Outcomes of Philadelphia Chromosome-Negative Myeloproliferative Neoplasms?
BACKGROUND: Philadelphia chromosome-negative myeloproliferative neoplasms (MPN) are a group of hematologic malignancies with known vascular complications. The role race and ethnicity play in these complications is less defined. We aimed to further evaluate the role of race in patients without a history of previous thrombotic or hemorrhagic events.
METHODS: In this retrospective study, 300 adult patients with MPN were included; 270 (90.0%) were White and 30 (10.0%) were non-White. The non-White group primarily consisted of African American or Black (26 patients), followed by others. Median age at diagnosis was 58 years for White patients and 61.5 years for non-White patients. The interaction between outcomes and vascular events with race was evaluated using multivariate logistical regression models.
RESULTS: The incidence of thrombotic events was inversely correlated with age at diagnosis, with younger patients demonstrating a higher rate of thrombotic events over time (p < .001). The incidence of thrombotic or hemorrhagic events did not differ between White and non-White patients. A statistically significant difference in median survival was observed between White and non-White patients: 29 years (95% confidence interval [CI]: 21.8-not reached) versus 13 years (95% CI: 5.7-22.7), respectively (p = .016).
CONCLUSION: This study did not find a significant difference in the rate of thrombotic or hemorrhagic events between White and non-White patients with MPN but suggested that non-White patients had significantly shorter median survival than White patients. Such observations may inform future studies to further characterize racial disparities in outcomes
Topical Application of an Irreversible Small Molecule Inhibitor of Lysyl Oxidases Ameliorates Skin Scarring and Fibrosis
Scarring is a lifelong consequence of skin injury, with scar stiffness and poor appearance presenting physical and psychological barriers to a return to normal life. Lysyl oxidases are a family of enzymes that play a critical role in scar formation and maintenance. Lysyl oxidases stabilize the main component of scar tissue, collagen, and drive scar stiffness and appearance. Here we describe the development and characterisation of an irreversible lysyl oxidase inhibitor, PXS-6302. PXS-6302 is ideally suited for skin treatment, readily penetrating the skin when applied as a cream and abolishing lysyl oxidase activity. In murine models of injury and fibrosis, topical application reduces collagen deposition and cross-linking. Topical application of PXS-6302 after injury also significantly improves scar appearance without reducing tissue strength in porcine injury models. PXS-6302 therefore represents a promising therapeutic to ameliorate scar formation, with potentially broader applications in other fibrotic diseases
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