δ13C and δ15N in the endangered Kemp’s ridley sea turtle Lepidochelys kempii after the Deepwater Horizon oil spill

The Deepwater Horizon explosion in April 2010 and subsequent oil spill released 3.19 × 106 barrels (5.07 × 108 l) of MC252 crude oil into important foraging areas of the endangered Kemp’s ridley sea turtle Lepidochelys kempii (Lk) in the northern Gulf of Mexico (GoM). We measured δ13C and δ15N in scute biopsy samples from 33 Lk nesting in Texas during the period 2010 to 2012. Of these, 27 were equipped with satellite transmitters and were tracked to traditional foraging areas in the northern GoM after the spill. Differences in δ13C between the oldest and newest scute layers from 2010 nesters were not significant, but δ13C in the newest layers from 2011 and 2012 nesters was significantly lower compared to 2010. δ15N differences were not statis- tically significant. Collectively, the stable isotope and tracking data indicate that the lower δ13C values reflect the incorporation of oil rather than changes in diet or foraging area. Discriminant analysis indicated that 51.5% of the turtles sampled had isotope signatures indicating oil exposure. Growth of the Lk population slowed in the years following the spill. The involvement of oil exposure in recent population trends is unknown, but long-term effects may not be evident for many years. Our results indicate that C isotope signatures in scutes may be useful biomarkers of sea turtle exposure to oil

The Effect of Language Type and Perceived Controllability on Stigma and Compassion

Previous research suggests that mental health stigma creates significant barriers to treatment seeking and adherence, diminishes treatment outcomes, and motivates social rejection towards people experiencing mental illness; by contrast, compassion seems to offer protective effects, improving treatment outcomes and helping behavior. The current work extends the established literature by experimentally examining the independent and interactive effects of two factors theorized to influence stigma and compassion: controllability and language. Participants read vignettes about hypothetical mental illnesses explained with a genetic attribution (indicating low controllability) or a behavioral attribution (indicating high controllability) and completed measures of perceived controllability, stigma, and compassion. We found that genetic etiology, compared to behavioral etiology, decreased stigma and increased compassion. Although not statistically significant, preliminary evidence suggests that language might interact with etiology to affect stigma. In the behavioral etiology condition, identity-first language (compared to person-first) exacerbated stigma, whereas, in the genetic etiology condition, this effect was descriptively reversed, though statistically nonsignificant. Our findings provide evidence that emphasizing the contribution of uncontrollable factors (e.g., genetics) to psychopathology could help reduce stigma and increase compassion for people experiencing mental illness. Language may also interact with controllability to inform stigma. This work could aid in advising empathetic and supportive language practices dependent on condition characteristics (e.g., perceived controllability), however, replication is needed to demonstrate the reliability of these effects

δ13C and δ15N in the endangered Kemp’s ridley sea turtle Lepidochelys kempii after the Deepwater Horizon oil spill

The Deepwater Horizon explosion in April 2010 and subsequent oil spill released 3.19 × 106 barrels (5.07 × 108 l) of MC252 crude oil into important foraging areas of the endangered Kemp’s ridley sea turtle Lepidochelys kempii (Lk) in the northern Gulf of Mexico (GoM). We measured δ13C and δ15N in scute biopsy samples from 33 Lk nesting in Texas during the period 2010 to 2012. Of these, 27 were equipped with satellite transmitters and were tracked to traditional foraging areas in the northern GoM after the spill. Differences in δ13C between the oldest and newest scute layers from 2010 nesters were not significant, but δ13C in the newest layers from 2011 and 2012 nesters was significantly lower compared to 2010. δ15N differences were not statis- tically significant. Collectively, the stable isotope and tracking data indicate that the lower δ13C values reflect the incorporation of oil rather than changes in diet or foraging area. Discriminant analysis indicated that 51.5% of the turtles sampled had isotope signatures indicating oil exposure. Growth of the Lk population slowed in the years following the spill. The involvement of oil exposure in recent population trends is unknown, but long-term effects may not be evident for many years. Our results indicate that C isotope signatures in scutes may be useful biomarkers of sea turtle exposure to oil

Intranasal administration of mesenchymal stem cells ameliorates the abnormal dopamine transmission system and inflammatory reaction in the R6/2 mouse model of Huntington disease

Intrastriatal administration of mesenchymal stem cells (MSCs) has shown beneficial effects in rodent models of Huntington disease (HD). However, the invasive nature of surgical procedure and its potential to trigger the host immune response may limit its clinical use. Hence, we sought to evaluate the non-invasive intranasal administration (INA) of MSC delivery as an effective alternative route in HD. GFP-expressing MSCs derived from bone marrow were intranasally administered to 4-week-old R6/2 HD transgenic mice. MSCs were detected in the olfactory bulb, midbrain and striatum five days post-delivery. Compared to phosphate-buffered saline (PBS)-treated littermates, MSC-treated R6/2 mice showed an increased survival rate and attenuated circadian activity disruption assessed by locomotor activity. MSCs increased the protein expression of DARPP-32 and tyrosine hydroxylase (TH) and downregulated gene expression of inflammatory modulators in the brain 7.5 weeks after INA. While vehicle treated R6/2 mice displayed decreased Iba1 expression and altered microglial morphology in comparison to the wild type littermates, MSCs restored both, Iba1 level and the thickness of microglial processes in the striatum of R6/2 mice. Our results demonstrate significantly ameliorated phenotypes of R6/2 mice after MSCs administration via INA, suggesting this method as an effective delivering route of cells to the brain for HD therapy

DU Undergraduate Showcase: Research, Scholarship, and Creative Works

DU Undergraduate Showcase: Research, Scholarship, and Creative Work

Structural Basis of Cytotoxicity Mediated by the Type III Secretion Toxin ExoU from Pseudomonas aeruginosa

The type III secretion system (T3SS) is a complex macromolecular machinery employed by a number of Gram-negative pathogens to inject effectors directly into the cytoplasm of eukaryotic cells. ExoU from the opportunistic pathogen Pseudomonas aeruginosa is one of the most aggressive toxins injected by a T3SS, leading to rapid cell necrosis. Here we report the crystal structure of ExoU in complex with its chaperone, SpcU. ExoU folds into membrane-binding, bridging, and phospholipase domains. SpcU maintains the N-terminus of ExoU in an unfolded state, required for secretion. The phospholipase domain carries an embedded catalytic site whose position within ExoU does not permit direct interaction with the bilayer, which suggests that ExoU must undergo a conformational rearrangement in order to access lipids within the target membrane. The bridging domain connects catalytic domain and membrane-binding domains, the latter of which displays specificity to PI(4,5)P2. Both transfection experiments and infection of eukaryotic cells with ExoU-secreting bacteria show that ExoU ubiquitination results in its co-localization with endosomal markers. This could reflect an attempt of the infected cell to target ExoU for degradation in order to protect itself from its aggressive cytotoxic action

Green Immigrants: The Plants that Transformed America

Recounts the histories, lore, romance, and uses of nearly one hundred plants, including African violets and apple trees that have been brought to the United States from other countries.https://scholar.dominican.edu/cynthia-stokes-brown-books-american-history/1016/thumbnail.jp

Proximity

Haley Shaver explores what it means to just dance in the middle of the COVID-19 pandemic. Her piece, set atop a parking garage, dives into movement for movement’s sake. The duet with Claire McDermott, a dance senior from Lexington, is meant to be an analysis of organic, unifying movements set against the backdrop of the isolating times of COVID-19

A Deep Dive Into Instagram's Top Skinfluencers

We characterized skinfluencers from various training backgrounds and compared their posts on Instagram featuring skin care products

Effects of Controllability and Language on Stigma Toward Mental Illness

Although past work consistently demonstrates perceivers stigmatize mental illness; which dimensions of stigma are relevant for specific conditions remains debated (Brohan et al., 2010). In the current work, we manipulated (between subjects) the controllability of fictitious mental illnesses and examined participants stigmatization across six dimensions (Fear, Help, Forcing Treatment, and Negative Emotions; Brown, 2008). We also examined whether effects of controllability were moderated by language (within subjects; person-first vs identity-first). We consistently found effects of controllability such that participants in the low (compared to high) condition responded with more fear, empathy, negative emotion, and intention to force treatment, but also attributed less responsibility and reported less tendency to help. Participants responded with more negative emotion toward a condition describe with person-first (relative to identity-first). We found no evidence that language moderated effects of controllability. This work highlights the multifaceted nature of mental health stigma, and suggests that controllability may be an important, but nuanced, factor in mental health stigma