Posttraumatic Stress Symptoms and Posttraumatic Cognitions in the Wake of the Death of Michael Brown.

On August 9, 2014, Michael Brown was shot and killed by police officer Darren Wilson in Ferguson Missouri, sparking protests and civil unrest. Three studies have yielded inconsistent findings regarding the presence of posttraumatic stress symptoms (PTSSs) in the aftermath of the unrest in Ferguson. Additional work is needed to understand how exposure to community-level stressors may correspond with trauma-related outcomes, as well as accounting for knowledge of, and engagement in the events.

Criterion A and Non-Criterion A Racial Discrimination Experiences, Posttraumatic Stress Symptoms, and Posttraumatic Cognitions Among Black or African Americans.

Racial discrimination is an unfortunately common experience for Black Americans with detrimental physical and mental health consequences. Prior research has established an association between discrimination and posttraumatic stress symptoms (PTSS); yet, trauma-related cognitions have not been studied. The majority of the existing empirical work in this area has not examined specific forms of discrimination experiences, despite potential key differences in these adversities.

An investigation of the associations between trauma exposure, racial stereotypes, and racist beliefs.

Objective: Given the concerning rise in hate crimes in recent years, it is critical to better understand factors associated with racist beliefs. As suggested by terror management theory (TMT), trauma exposure and posttraumatic stress symptoms (PTSS) may activate existential distress and anxiety, which may strengthen worldviews, including prejudiced beliefs (Greenberg & Kosloff, 2008; Weise et al., 2012).

Fluorescence-resonance-energy-transfer-based assay to estimate modulation of TDP1 activity through arginine methylation.

Tyrosyl DNA phosphodiesterase (TDP1) is a DNA repair enzyme that hydrolyzes the phosphotyrosyl linkage between 3'-DNA-protein crosslinks such as stalled topoisomerase 1 cleavage complexes (Top1cc). Here, we present a fluorescence-resonance-energy-transfer-(FRET) based assay to estimate modulation of TDP1 activity through arginine methylation. We describe steps for TDP1 expression and purification and estimating TDP1 activity using fluorescence-quenched probes mimicking Top1cc.

Interplay between symmetric arginine dimethylation and ubiquitylation regulates TDP1 proteostasis for the repair of topoisomerase I-DNA adducts.

Tyrosyl-DNA phosphodiesterase (TDP1) hydrolyzes the phosphodiester bond between a DNA 3' end and a tyrosyl moiety and is implicated in the repair of trapped topoisomerase I (Top1)-DNA covalent complexes (Top1cc). Protein arginine methyltransferase 5 (PRMT5) catalyzes arginine methylation of TDP1 at the residues R361 and R586. Here, we establish mechanistic crosstalk between TDP1 arginine methylation and ubiquitylation, which is critical for TDP1 homeostasis and cellular responses to Top1 poisons.

A pilot study adapting and validating the Harvard Trauma Questionnaire (HTQ) and PTSD checklist-5 (PCL-5) with Indian women from slums reporting gender-based violence.

Background: Despite high rates of gender-based violence (GBV) in India, culturally sensitive measures that examine universal and culturally relevant trauma reactions are lacking. Although the Harvard Trauma Questionnaire (HTQ) has been used in India, no study has adapted the measure in full for use with this population. Similarly, the  PTSD checklist-5 (PCL-5) has not yet been validated in India.

Phosphorylation of NANOG by casein kinase I regulates embryonic stem cell self-renewal.

The self-renewal efficiency of mouse embryonic stem cells (ESCs) is determined by the concentration of the transcription factor NANOG. While NANOG binds thousands of sites in chromatin, the regulatory systems that control DNA binding are poorly characterised. Here, we show that NANOG is phosphorylated by casein kinase I, and identify target residues.

Cardiomyopathy in limb girdle muscular dystrophy R9, FKRP related.

Introduction: Reported frequencies of cardiomyopathy in limb girdle muscular dystrophy R9 (LGMDR9) vary. We describe the frequency and age at onset of cardiomyopathy in an LDMDR9 cohort.

Methods: Echocardiograms from 56 subjects (157 echocardiograms) with LGMDR9 were retrospectively reviewed.

Exploratory study of a screening measure for polycystic ovarian syndrome, quality of life assessment, and neuropsychological evaluation.

Background: The universally adopted 2018 PCOS medical diagnostic and treatment guidelines for Polycystic Ovarian Syndrome (PCOS) cites the need for a brief screening measure that can be easily administered in the clinical care setting. We evaluate a 12-item questionnaire emphasizing the medical symptoms of PCOS with a group of women with PCOS as well as comparison samples of college women not diagnosed with PCOS.

Method: Of 120 undergraduate psychology women 18 to 41 years of age, 86 screened negative on a 12-item PCOS symptoms inventory.

The Covid-19 crisis as a career shock: Implications for careers and vocational behavior.

The covid-19 pandemic is a for many people across the globe. In this article, we reflect on how insights from the literature on career shocks can help us understand the career consequences of the pandemic and offer suggestions for future research in this area. In particular, we offer three "key lessons".

Structural basis for DNA 3'-end processing by human tyrosyl-DNA phosphodiesterase 1.

Tyrosyl-DNA phosphodiesterase (Tdp1) is a DNA 3'-end processing enzyme that repairs topoisomerase 1B-induced DNA damage. We use a new tool combining site-specific DNA-protein cross-linking with mass spectrometry to identify Tdp1 interactions with DNA. A conserved phenylalanine (F259) of Tdp1, required for efficient DNA processing in biochemical assays, cross-links to defined positions in DNA substrates.

Use of mariner transposases for one-step delivery and integration of DNA in prokaryotes and eukaryotes by transfection.

Delivery of DNA to cells and its subsequent integration into the host genome is a fundamental task in molecular biology, biotechnology and gene therapy. Here we describe an IP-free one-step method that enables stable genome integration into either prokaryotic or eukaryotic cells. A synthetic mariner transposon is generated by flanking a DNA sequence with short inverted repeats.

A bend, flip and trap mechanism for transposon integration.

Cut-and-paste DNA transposons of the mariner/Tc1 family are useful tools for genome engineering and are inserted specifically at TA target sites. A crystal structure of the mariner transposase Mos1 (derived from Drosophila mauritiana), in complex with transposon ends covalently joined to target DNA, portrays the transposition machinery after DNA integration. It reveals severe distortion of target DNA and flipping of the target adenines into extra-helical positions.

Structural role of the flanking DNA in mariner transposon excision.

During cut-and-paste mariner/Tc1 transposition, transposon DNA is cut precisely at its junction with flanking DNA, ensuring the transposon is neither shortened nor lengthened with each transposition event. Each transposon end is flanked by a TpA dinucleotide: the signature target site duplication of mariner/Tc1 transposition. To establish the role of this sequence in accurate DNA cleavage, we have determined the crystal structure of a pre-second strand cleavage mariner Mos1 transpososome.

Biochemical characterization and comparison of two closely related active mariner transposases.

Most DNA transposons move from one genomic location to another by a cut-and-paste mechanism and are useful tools for genomic manipulations. Short inverted repeat (IR) DNA sequences marking each end of the transposon are recognized by a DNA transposase (encoded by the transposon itself). This enzyme cleaves the transposon ends and integrates them at a new genomic location.

Structural basis of Mos1 transposase inhibition by the anti-retroviral drug Raltegravir.

DNA transposases catalyze the movement of transposons around genomes by a cut-and-paste mechanism related to retroviral integration. Transposases and retroviral integrases share a common RNaseH-like domain with a catalytic DDE/D triad that coordinates the divalent cations required for DNA cleavage and integration. The anti-retroviral drugs Raltegravir and Elvitegravir inhibit integrases by displacing viral DNA ends from the catalytic metal ions.

Biochemical and immunological characterization of Toxoplasma gondii macrophage migration inhibitory factor.

Macrophage migration inhibitory factor (MIF) is a proinflammatory molecule in mammals that, unusually for a cytokine, exhibits tautomerase and oxidoreductase enzymatic activities. Homologues of this well conserved protein are found within diverse phyla including a number of parasitic organisms. Herein, we produced recombinant histidine-tagged Toxoplasma gondii MIF (TgMIF), a 12-kDa protein that lacks oxidoreductase activity but exhibits tautomerase activity with a specific activity of 19.

Structure of a complex phosphoglycan epitope from gp72 of Trypanosoma cruzi.

The parasitic protozoan organism Trypanosoma cruzi is the causative agent of Chagas disease. The insect vector-dwelling epimastigote form of the organism expresses a low abundance glycoprotein associated with the flagellum adhesion zone, called gp72. The gp72 glycoprotein was first identified with an anti-carbohydrate IgG3 monoclonal antibody called WIC29.

Solution conformations of early intermediates in Mos1 transposition.

DNA transposases facilitate genome rearrangements by moving DNA transposons around and between genomes by a cut-and-paste mechanism. DNA transposition proceeds in an ordered series of nucleoprotein complexes that coordinate pairing and cleavage of the transposon ends and integration of the cleaved ends at a new genomic site. Transposition is initiated by transposase recognition of the inverted repeat sequences marking each transposon end.

Chemical structure of Trichomonas vaginalis surface lipoglycan: a role for short galactose (β1-4/3) N-acetylglucosamine repeats in host cell interaction.

The extracellular parasite Trichomonas vaginalis contains a surface glycoconjugate that appears to mediate parasite-host cell interaction via binding to human galectin-1. This glycoconjugate also elicits cytokine production from human vaginal epithelial cells, implicating its role in modulation of host immune responses. We have analyzed the structure of this glycoconjugate, previously described to contain the sugars rhamnose (Rha), N-acetylglucosamine (GlcNAc), galactose (Gal), xylose (Xyl), N-acetylgalactosamine (GalNAc), and glucose (Glc), using gas chromatograph mass spectrometry (GC-MS), matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF), electrospray MS/MS, and nuclear magnetic resonance (NMR), combined with chemical and enzymatic digestions.

The relationship between organizational leadership for safety and learning from patient safety events.

Objective: To examine the relationship between organizational leadership for patient safety and five types of learning from patient safety events (PSEs).

Study Setting: Forty-nine general acute care hospitals in Ontario, Canada.

Study Design: A nonexperimental design using cross-sectional surveys of hospital patient safety officers (PSOs) and patient care managers (PCMs).

Omega-3 fatty acid supplements in women at high risk of breast cancer have dose-dependent effects on breast adipose tissue fatty acid composition.

Background: Preclinical evidence of the preventive benefits of omega-3 (n-3) polyunsaturated fatty acids (PUFAs) in breast cancer continues to fuel interest in the potential role of dietary fat content in reducing breast cancer risk. The dose of fish-oil/omega-3 PUFAs needed to achieve maximal target tissue effects for breast cancer prevention remains undefined.

Objective: To determine the dose effects of omega-3 fatty acids on breast adipose tissue fatty acid profiles, we conducted a study of 4 doses of omega-3 PUFAs in women at high risk of breast cancer.

Molecular architecture of the Mos1 paired-end complex: the structural basis of DNA transposition in a eukaryote.

A key step in cut-and-paste DNA transposition is the pairing of transposon ends before the element is excised and inserted at a new site in its host genome. Crystallographic analyses of the paired-end complex (PEC) formed from precleaved transposon ends and the transposase of the eukaryotic element Mos1 reveals two parallel ends bound to a dimeric enzyme. The complex has a trans arrangement, with each transposon end recognized by the DNA binding region of one transposase monomer and by the active site of the other monomer.