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91.
It has been firmly established that opening and closing the eyes strongly modulate the electro- and magnetoencephalography (EEG and MEG) signals acquired during wakeful rest. Certain features of the resting EEG are altered in chronic alcoholics and their offspring, and have been proposed as biomarkers for alcoholism. Spontaneous brain oscillations are also affected by pharmacological manipulations, but the spectral and spatial characteristics of these changes are not clear. This study examined effects of the eyes-open (EO) and eyes-closed (EC) resting paradigm and alcohol challenge on the spatial profile of spontaneous MEG and EEG oscillations. Whole-head MEG and scalp EEG signals were acquired simultaneously from healthy social drinkers (n = 17) who participated in both alcohol (0.6 g/kg ethanol for men, 0.55 g/kg for women) and placebo conditions in a counterbalanced design. Power of the signal was calculated with Fast Fourier Transform and was decomposed into its constituent theta (4–7 Hz), alpha (8–12 Hz), and beta (15–20 Hz) frequency bands. High-resolution structural MRI images were additionally obtained from all participants and used to constrain distributed minimum norm inverse source power estimates. The spatial estimates of the main generator nodes were in agreement with studies using a combined fMRI-EEG approach. Alpha band oscillations dominated the spectral profile and their source was estimated to the medial parieto-occipital area. Power in theta and beta bands was weaker overall and their sources were estimated to a more focal medial prefrontal area. EO and EC manipulation most strongly modulated power in the alpha band, but a wide-band power increase was observed during the EC condition. Alcohol intoxication increased alpha power, particularly during the EC condition. Application of this methodology to cohorts of chronic alcoholics or individuals at risk could potentially provide insight into the neural basis of oscillatory differences that may be predictive of the vulnerability to alcoholism.  相似文献   
92.

Objectives

Dental composite materials come into direct contact with oral tissue, especially gingival cells. This study was performed to evaluate possible DNA damage to gingival cells exposed to resin composite dental materials.

Materials and methods

Class V restorations were placed in 30 adult patients using two different composite resins. The epithelial cells of the gingival area along the composite restoration were sampled prior to and after 7, 30, and 180 days following the restoration of the tooth. DNA damage was analysed by comet and micronucleus assays in gingival exfoliated epithelial cells.

Results

The results showed significantly higher comet assay parameters (tail length and % DNA in the tail) within periods of 30 and 180 days. The micronucleus test for the same exposure time demonstrated a higher number of cells with micronuclei, karyolysis, and nuclear buds. Results did not reveal any difference between the two composite materials for the same duration of exposure.

Conclusion

Based on the results, we can conclude that the use of composite resins causes cellular damage. As dental composite resins remain in intimate contact with oral tissue over a long period of time, further research on their possible genotoxicity is advisable.

Clinical relevance

Long-term exposure of gingival cells to two different composite materials demonstrated certain DNA damage. However, considering the significant decline in micronuclei frequency after 180 days and efficiency in the repair of primary DNA damage, the observed effects could not be indicated as biologically relevant.  相似文献   
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Objectives:To estimate the prevalence of insufficient physical activity and excessive screen time among adolescents living in cities participating in the Healthy Cities Program (HCP) and cities not running the program in the Qassim region of Saudi Arabia.Methods:We surveyed 1133 adolescents from the Qassim region using systematic random sampling between April and September 2017. Multivariable logistic regression analyses were conducted to investigate the predictors of insufficient levels of PA and excessive screen time.Results:The prevalence of <60 minutes of moderate- to vigorous-intensity physical activity/day was 82.4% and <3 days of vigorous intensity physical activity/week among adolescents was 59%. There was no significant association between living in healthy cities (HCPs) and insufficient levels of physical activity. The odds of excessive screen time were higher in HCPs than in cities not running the program (NHCPs) (OR: 1.49). The odds of insufficient daily PA (OR: 2.19) are higher among girls than boys. Increasing age is positively associated with insufficient weekly PA (OR: 1.19). The prevalence of excessive recreational screen time is 84.6% with higher odds in HCPs than in NHCPs (OR: 1.51).Conclusion:Our findings report a lack of evidence of any impact of the HCP on adolescents’ physical activity behaviors. This outcome warrants a further in-depth evaluation of the process and outcomes of the HCP in Saudi Arabia.  相似文献   
96.
The genus Aspergillus is widely distributed in terrestrial and marine environments. In the marine environment, several Aspergillus species have proved their potential to produce a plethora of secondary metabolites including polyketides, sterols, fatty acids, peptides, alkaloids, terpenoids and miscellaneous compounds, displaying a variety of pharmacological activities such as antimicrobial, cytotoxicity, anti-inflammatory and antioxidant activity. From the beginning of 2015 until December 2020, about 361 secondary metabolites were identified from different marine Aspergillus species. In our review, we highlight secondary metabolites from various marine-derived Aspergillus species reported between January 2015 and December 2020 along with their biological potential and structural aspects whenever applicable.

The genus Aspergillus is widely distributed in terrestrial and marine environments.  相似文献   
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98.

Our objective was to investigate the prevalence and the environmental determinants of alcohol use among students in the region of Sfax in Tunisia. We carried out a cross-sectional study among 315 middle and high school students. We used the Alcohol Use Disorders Identification Test (AUDIT) to identify risky alcohol consumption, and we used the Parenting Styles and Dimensions Questionnaire (PSDQ) to assess the students’ perceptions of their parents’ parenting styles. The results show that 19.7% reported drinking alcohol at least once in their lifetime. Among them, 21% scored as dependent alcohol users, according to the AUDIT. Those who drank alcohol at least once were more likely to have parents with a permissive parenting style (p < 0.001; Cramer’s V = 0.287), and a father (p < 0.001; Cramer’s V = 0.258), a mother (p = 0.025; Cramer’s V = 0.158), or a friend (p < 0.001; Cramer’s V = 0.341) who drinks. Students perceiving their parents’ parenting style as permissive had the highest AUDIT score (p = 0.005; partial η2 = 0.132). The authoritarian style score was significantly higher for students who were current alcohol users (p = 0.028; Cohen’s d = 0.57). Our study highlights the influence of peers, family drinking, and parenting styles on alcohol use among middle and high school students. Therefore, particular attention should be given to students that are at risk of having the abovementioned environmental determinants of alcohol use. And, prevention strategies should involve parents, as well as enhanced guidance and counseling for these students.

  相似文献   
99.
European Archives of Oto-Rhino-Laryngology - Behavioral evaluation of language development is an important index for the usefulness of cochlear implantation. However, it could not apply to infants...  相似文献   
100.
Journal of Neurology - We aimed to determine suicide risk and lifetime suicidal ideation in Parkinson disease (PD) patients versus controls and how depression, demoralization, and insomnia are...  相似文献   
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