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Taurine, a non-proteogenic amino acid and commonly used nutritional supplement, can protect various tissues from degeneration associated with the action of the DNA-damaging chemotherapeutic agent cisplatin. Whether and how taurine protects human ovarian cancer (OC) cells from DNA damage caused by cisplatin is not well understood. We found that OC ascites-derived cells contained significantly more intracellular taurine than cell culture-modeled OC. In culture, elevation of intracellular taurine concentration to OC ascites-cell-associated levels suppressed proliferation of various OC cell lines and patient-derived organoids, reduced glycolysis, and induced cell protection from cisplatin. Taurine cell protection was associated with decreased DNA damage in response to cisplatin. A combination of RNA sequencing, reverse-phase protein arrays, live-cell microscopy, flow cytometry, and biochemical validation experiments provided evidence for taurine-mediated induction of mutant or wild-type p53 binding to DNA, activation of p53 effectors involved in negative regulation of the cell cycle (p21), and glycolysis (TIGAR). Paradoxically, taurine's suppression of cell proliferation was associated with activation of pro-mitogenic signal transduction including ERK, mTOR, and increased mRNA expression of major DNA damage-sensing molecules such as DNAPK, ATM and ATR. While inhibition of ERK or p53 did not interfere with taurine's ability to protect cells from cisplatin, suppression of mTOR with Torin2, a clinically relevant inhibitor that also targets DNAPK and ATM/ATR, broke taurine's cell protection. Our studies implicate that elevation of intracellular taurine could suppress cell growth and metabolism, and activate cell protective mechanisms involving mTOR and DNA damage-sensing signal transducti. [ABSTRACT FROM AUTHOR]

Alkanes, single carbon methane to long‐chain hydrocarbons (e.g. hexadecane and tetradecane), are important carbon sources to anaerobic microbial communities. In anoxic environments, archaea are known to utilize and produce methane via the methyl‐coenzyme M reductase enzyme (MCR). Recent explorations of new environments, like deep sea sediments, that have coupled metagenomics and cultivation experiments revealed divergent MCRs, also referred to as alkyl‐coenzyme M reductases (ACRs) in archaea, with similar mechanisms as the C1 utilizing canonical MCR mechanism. These ACR enzymes have been shown to activate other alkanes such as ethane, propane and butane for subsequent degradation. The reversibility of canonical MCRs suggests that these non‐methane‐activating homologues (ACRs) might have similar reversibility, perhaps mediated by undiscovered lineages that produce alkanes under certain conditions. The discovery of these alternative alkane utilization pathways holds significant promise for a breadth of potential biotechnological applications in bioremediation, energy production and climate change mitigation. [ABSTRACT FROM AUTHOR]

Organic sulfur plays a crucial role in the biogeochemistry of aquatic sediments, especially in low sulfate (< 500 μM) environments like freshwater lakes and the Earth's early oceans. To better understand organic sulfur cycling in these systems, we followed organic sulfur in the sulfate‐poor (< 40 μM) iron‐rich (30–80 μM) sediments of Lake Superior from source to sink. We identified microbial populations with shotgun metagenomic sequencing and characterized geochemical species in porewater and solid phases. In anoxic sediments, we found an active sulfur cycle fueled primarily by oxidized organic sulfur. Sediment incubations indicated a microbial capacity to hydrolyze sulfonates, sulfate esters, and sulfonic acids to sulfate. Gene abundances for dissimilatory sulfate reduction (dsrAB) increased with depth and coincided with sulfide maxima. Despite these indicators of sulfide formation, sulfide concentrations remain low (< 40 nM) due to both pyritization and organic matter sulfurization. Immediately below the oxycline, pyrite accounted for 13% of total sedimentary sulfur. Both free and intact lipids in this same interval accumulated disulfides, indicating rapid sulfurization even at low concentrations of sulfide. Our investigation revealed a new model of sulfur cycling in a low‐sulfate environment that likely extends to other modern lakes and possibly the ancient ocean, with organic sulfur both fueling sulfate reduction and consuming the resultant sulfide. [ABSTRACT FROM AUTHOR]

Sexual health education (SHE) is an important rehabilitation component for acute coronary syndrome (ACS) survivors but is not routinely provided. This study's purpose was to explore healthcare providers' experiences of providing SHE to ACS survivors in cardiac rehabilitation programs to identify best practices. This qualitative study used convenience sampling and an interpretive descriptive design. Inclusion criteria were a healthcare provider employed within a cardiac rehabilitation program in a Western Canadian province. Eight cardiac rehabilitation healthcare providers volunteered to participate. The first author conducted semi-structured, digitally recorded interviews that were transcribed verbatim. The interviews were guided by a semi-structured interview guide anchored in the strengths-based, sex positive guiding frameworks. A reflective journal and socio-demographic forms served as additional data sources. Data were analyzed using open, axial, and selective coding as well as constant comparative analysis. Credibility was ensured through peer-reviewed evaluation criteria. Eight healthcare providers participated in the study. Participants equated sexuality and sexual health with physical activity and physical health. Findings identified philosophical perspectives and several barriers and facilitators that impact SHE provision. Participants offered strategies that may be used in practice and their recommendations provide a beginning foundation to improve cardiac rehabilitation programs and the health of ACS survivors. Healthcare providers in cardiac rehabilitation programs described their SHE experiences as "just think of it as sexercise." Facilitation of SHE is important as previous studies found that SHE may reduce fear, depression, and anxiety and increase the return to sexual activity among ACS survivors. Sexual health doesn't need to be a taboo topic. Approach sexual health conversations by thinking of it as "sexercise". Don't let silos stop sexual health education – talk to your coworkers and patients about sexual health. Knowledge about sexual health, timing of sexual health education, and communication between care providers and patients are important factors in delivery of sexual health education. [ABSTRACT FROM AUTHOR]

A literary criticism of the book "At Penpoint: African Literatures, Postcolonial Studies, and the Cold War" by Monica Popescu is presented. Topics discussed include influence of Ngũgĩ wa Thiong'o, a Kenyan Kikuyu writer, on the title of the book; scholarly field of African literature including magazines such as "Black Orpheus" in Nigeria and "Transition" in Uganda; and Cold War culture and ideology along with aesthetic decolonization in Africa.

If 'the contemporary' is the heading under which scholars study recent literary, artistic, and cultural forms, what exactly is it? Is it a period? A style? A type of content - networks, finance, or climate change - that feels diagnostic of the present? For literary scholars, the contemporary is a persistently moving target. Rather than stating when it is, we consider critical methods of reading the contemporary alongside the objects they favor and promote. We thereby disrupt the idea of an accepted canon of contemporary fiction by showing the wide array of texts contemporary critics do in fact study. This survey covers contemporary approaches to fiction that find their starting points in the neoliberal economy, in systems and institutions, in theories of the Anthropocene and world literature, and in critical race studies. We conclude with the proliferating 'posts' of contemporary literature and theory - post-human, post-racial, and even post-postmodern - and with our intuitions about the temporal and historical function of literary form in contemporary fiction. [ABSTRACT FROM AUTHOR]

In the early 1960s two editions of Chinua Achebe's Things Fall Apart were published with competing sets of illustrations. The first, by Dennis Carabine, illustrates a realist novel, the second, by Uche Okeke, a modernist one. Reading Achebe's iconic novel through its early publication history and for its visual images shows how the famous ending of Things Fall Apart turns, stylistically, to the impenetrable flatness of the modernist surface. At mid-century, modernist style could be made to serve realist imperatives, and Achebe's flat style challenges colonial modes of literary representation and the myth of modernist primitivism in the visual arts. This essay stresses the importance of the visual image to mid-century anglophone literature and the importance of modernist style to the poetics of decolonization [ABSTRACT FROM AUTHOR]