Mutagenic effects of abasic and oxidized abasic lesions in Saccharomyces cerevisiae

2-Deoxyribonolactone (L) and 2-deoxyribose (AP) are abasic sites that are produced by ionizing radiation, reactive oxygen species and a variety of DNA damaging agents. The biological processing of the AP site has been examined in the yeast Saccharomyces cerevisiae. However, nothing is known about how L is processed in this organism. We determined the bypass and mutagenic specificity of DNA containing an abasic site (AP and L) or the AP analog tetrahydrofuran (F) using an oligonucleotide transformation assay. The tetrahydrofuran analog and L were bypassed at 10-fold higher frequencies than the AP lesions. Bypass frequencies of lesions were greatly reduced in the absence of Rev1 or Polζ (rev3 mutant), but were only marginally reduced in the absence of Polη (rad30 mutant). Deoxycytidine was the preferred nucleotide inserted opposite an AP site whereas dA and dC were inserted at equal frequencies opposite F and L sites. In the rev1 and rev3 strains, dA was the predominant nucleotide inserted opposite these lesions. Overall, we conclude that both Rev1 and Polζ are required for the efficient bypass of abasic sites in yeast

Depression, stigma and social isolation: The psychosocial trifecta of primary chronic cutaneous lupus erythematosus, a cross-sectional and path analysis

OBJECTIVE: Depression is common in individuals with chronic cutaneous lupus erythematosus (CCLE). However, how CCLE may impact patients\u27 psychological well-being is poorly understood, particularly among disproportionally affected populations. We examined the relationships between depression and psychosocial factors in a cohort of predominantly Black patients with primary CCLE (CCLE without systemic manifestations). METHODS: Cross-sectional assessment of individuals with dermatologist-validated diagnosis of primary CCLE. NIH-PROMIS short-forms were used to measure depression, disease-related stigma, social isolation and emotional support. Linear regression analyses (ɑ=0.05) were used to test an a priori conceptual model of the relationship between stigma and depression and the effect of social isolation and emotional support on that association. RESULTS: Among 121 participants (87.6% women; 85.1% Black), 37 (30.6%) reported moderate to severe depression. Distributions of examined variables divided equally among those which did (eg, work status, stigma (more), social isolation (more), emotional support (less)) and did not (eg, age, sex, race, marital status) significantly differ by depression. Stigma was significantly associated with depression (b=0.77; 95% CI0.65 to 0.90), whereas social isolation was associated with both stigma (b=0.85; 95% CI 0.72 to 0.97) and depression (b=0.70; 95% CI0.58 to 0.92). After controlling for confounders, stigma remained associated with depression (b=0.44; 95% CI0.23 to 0.66) but lost significance (b=0.12; 95% CI -0.14 to 0.39) when social isolation (b=0.40; 95% CI 0.19 to 0.62) was added to the model. Social isolation explained 72% of the total effect of stigma on depression. Emotional support was inversely associated with depression in the univariate analysis; however, no buffer effect was found when it was added to the multivariate model. CONCLUSION: Our findings emphasise the psychosocial challenges faced by individuals living with primary CCLE. The path analysis suggests that stigmatisation and social isolation might lead to depressive symptoms. Early clinical identification of social isolation and public education demystifying CCLE could help reduce depression in patients with CCLE

Cross-sectional study of the effects of self-efficacy on fatigue and pain interference in black women with systemic lupus erythematosus: the role of depression, age and education

Objective While fatigue and pain are pervasive symptoms in SLE, self-efficacy can mitigate their intensity and impact on patients’ daily activity. We examined the relationships of these domains and their interactions with demographics and depression in black women with SLE.Methods This is a cross-sectional analysis of data collected among 699 black women with SLE. We used validated, self-reported measures of fatigue, pain interference, symptom self-efficacy, treatment self-efficacy and depression. Linear regression analyses were conducted to examine the relationships between each outcome (fatigue and pain interference) and each predictor (symptom self-efficacy and treatment self-efficacy), and the interaction of demographics and depression.Results We found inverse associations between fatigue and each of symptom self-efficacy (slope −0.556, p<0.001) and treatment self-efficacy (slope −0.282, p<0.001), as well as between pain interference and each of symptom self-efficacy (slope −0.394, p<0.001) and treatment self-efficacy (slope −0.152, p<0.001). After adjusting for confounders, symptom self-efficacy remained significantly associated with each outcome (adjusted slope −0.241 (p<0.001) and −0.103 (p=0.008) for fatigue and pain, respectively). The amount of decrease in fatigue and pain interference differed by depression severity (p<0.05 for the interaction of symptom self-efficacy and depression). The difference in fatigue by depression widened as symptom self-efficacy increased; the adjusted fatigue scores for moderate/severe depression compared with no depression were 6.8 and 8.7 points higher at mean and high symptom self-efficacy, respectively (p<0.001). Age and education significantly changed the relationship between outcomes and self-efficacy.Conclusions Symptom self-efficacy and treatment self-efficacy were inversely related to fatigue and pain interference in black women with SLE. Depression disproportionately increased the intensity of these outcomes. While older women with low symptom self-efficacy reported disproportionately higher pain interference, those with higher education and mean or high levels of symptom self-efficacy reported lower pain interference. These findings may help predict who might benefit most from self-efficacy-enhancing interventions