bluuebunny/crossref_metadata_2025 huggingface dataset:
Show Them You Care: Faculty Responsiveness Augments Student Buy‐in to Active Learning
Authors: Chen Xinnian , Cavanagh Andrew , Graham Mark
Published: June 2021

It has been well documented that positive teacher behavior can improve student motivation, self‐efficacy, and learning. However, less is known regarding the extent to which student‐faculty interactions can further benefit student learning within active learning classroom environments. In this study, we focus on the impact of faculty responsiveness on student learning by examining ways in which student perceptions of faculty responsiveness predict buy‐in to active learning.

To quantify student buy‐in to active learning, we used an Exposure‐Persuasion‐Identification‐Commitment (EPIC) process model. In addition, we explored potential predictors of buy‐in, including perceptions of instructor responsiveness and growth mindset. Instructor responsiveness was assessed using a student survey based on Reis and Clark's (2004) interpersonal relationship theoretical framework adapted by the authors for the classroom setting. We utilized a validated 3‐item measure to assess growth mindset among student participants.

We examined student (N=245) perceptions of instructor responsiveness as a key predictor of student performance in an undergraduate science course featuring active learning. Regression analyses indicated a statistically significant association between perceived instructor responsiveness and student buy‐in to active learning. Growth mindset (i.e., student views of intelligence as malleable) was also found to significantly predict buy‐in to active learning. Student buy‐in to active learning was positively associated both with engagement in self‐regulated learning, and with students' overall course performance. Interestingly, we found that perceived responsiveness also impacted students' views on intelligence, which in turn affects their likelihood of buy‐in. Implications for best practice in securing student buy‐in and engagement are discussed.

Support or Funding Information

NSF 1323079
First detailed anatomical study of bonobos exposes just‐so stories of human evolution, anatomy, variations, bipedalism and tool use
Authors: Diogo Rui
Published: June 2021

Just‐so stories are prominent in human evolution literature because of our tendency to create simple progressionist narratives about our history and how special and unique we are. One point that is particularly striking about such stories is how confident their authors are about the origin and evolution of our specific soft tissues and their ‘functional adaptations’, despite the fact that they are almost exclusively based on hard tissue data. How can we be so certain about stories on the evolution of human facial communication, bipedalism, tool use, or speech that were put forward without any phylogenetic analysis including muscle data or detailed knowledge of the internal anatomy of one of the two extant species more closely related to us, the bonobos? Here I show how many of these stories now becomes obsolete, after such a comprehensive knowledge is finally put together with the first detailed study of bonobo soft tissues. Each and every muscle that has been long accepted to be unique for humans and to provide ‘crucial singular functional adaptations’ for our bipedalism, tool use and/or vocal/facial communication, is actually present as variants or even as the normal phenotype in bonobos and/or other apes.

Support or Funding Information

This project has received funding from NSF grants 1516557 and 1440624 to RD.
Biomechanics and the Evolution of the Crocodyliform Skull
Authors: Sellers Kaleb C , Middleton Kevin M , Davis Julian L , Holliday Casey M
Published: June 2021

The evolution of the derived crocodyliform skull from that of basal suchians involved the acquisition of a number of functionally salient features. Skull flattening resulted in a reorganization of the jaw muscles and a rotation of the quadrate, placing the jaw joint caudal to the braincase. These changes were preceded by an expansion of the pterygoid buttress, which in crocodyliforms is elaborated into a second articulation of the skull with the mandible known as the pterygomandibular joint (PMJ). While the fossil record demonstrates the pattern of morphological changes, the biomechanics of the system is less well known. This study uses high‐fidelity biomechanical modeling to investigate muscle, bite, and joint force magnitude and orientation in Prestosuchus, protosuchians, and Alligator. We made finite element and free body models to estimate how individual muscles contribute to cranial forces. Osteological correlates of jaw muscle attachments informed reconstructed muscle maps on 3D models built through the Boneload computational modeling workflow. Three‐dimensional muscle force vectors were projected into ternary space to visualize how muscular geometry changes with osteology. The orientations of joint surface and joint reaction force were also compared. Results show a progressive increase in medially‐oriented muscle force along the lineage leading to crocodyliforms concomitant with the expansion of the pterygoid buttress and PMJ. Results also reveal that jaw joint reaction forces align with the quadrate across the transition in quadrate orientation, suggesting that a shift in muscular geometry in more derived taxa increased the rostral and medial components of jaw joint reaction force, thereby avoiding excessive bending of the suspensorium.

Support or Funding Information

NSF IOS‐1457319; NSF‐EAR 1631684; Missouri ResearchBoard; Missouri Research Council; University of Missouri Department of Pathology and Anatomical Sciences
Genetic and environmental factors that regulate tandem repeat variation in coding regions
Authors: Fuchs Stephen M
Published: June 2021

More than 10% of all proteins harbor a region of repetitive amino acid sequence. Instability within the DNA that codes for these sequences tunes protein function by varying the number of tandem repeats that are expressed and contributes to phenotypic diversity. Based on the repetitive C‐terminal domain of RNA polymerase II subunit Rpb1p, Our lab has developed a powerful reporter system for measuring expansion and contraction of tandem repeats in coding regions (Morrill et al., J. Biol. Chem, 2016). Here we use this system to identify the pathways involved in both repeat expansion and contraction in the budding yeast S. cerevisiae. We also uncovered a direct role between environmental stress and repeat variation and provide links to how TR variation may be contributing to organismal adaptation to stress.

Support or Funding Information

Army Research Office
Role of the Excluded Strand in DNA Unwinding by Hexameric Helicases
Authors: Trakselis Michael
Published: June 2021

Hexameric DNA helicases control both the initiation and elongation phases of DNA replication. It is well known that these toroidal enzymes encircle and translocate preferentially on one strand with specific polarities dependent on their families and organismal domains. The question remains as to what if any role the excluded strand has in the unwinding mechanism or coordination of activities at the replication fork. Over the past few years, there has been an increasing amount of evidence to suggest that the excluded‐strand plays a significant role during unwinding by interacting with the helicase's outer surface in a Steric Exclusion and Wrapping (SEW) mode. The implications are that the excluded strand interaction controls the kinetics of unwinding while maintaining the ssDNA product for handoff to other replication components.

We have investigated the interaction of the excluded strand with the outer surface of helicases in archaea, mitochondria, and bacteria using a variety of biochemical, biophysical, and genetic techniques. We have not only defined a minimal interaction path on the outer surface of these helicases, but we can also show that this interaction differentially controls the unwinding rate and efficiency. For the archaea MCM helicase, which has 3′‐5′ polarity, disruption of the excluded strand interaction inhibits unwinding consistent with a ratchet mechanism. Conversely, for the bacterial DnaB helicase, which has 5′‐3′ polarity, disruption increases the unwinding rate more consistent with a regulator‐type mechanism. The contrasting effects of the excluded strand interaction coupled with the opposing translocation polarities of these helicases will be discussed within the context of their respective replisomes.

Support or Funding Information

NSF‐1613534
Cracking the Interorganellar Communication Codes
Authors: de Souza Amancio J , Svozil Julia , Wang Jin‐Zheng , Ke Haiyan , Xiao Yanmei , Gruissem Wilhelm , Dehesh Katayoon
Published: June 2021

Inter‐organelle communication is essential for cellular homeostasis and stress adaptation. In plants, the metabolic hub is the chloroplast, which has a central role in tightly adjusting metabolic activities to environmental perturbations. Several small chloroplast molecules have been identified to be involved in signal transduction pathways that can modulate the transcription of nuclear genes. Despite its biological significance the underlying molecular mechanisms of chloroplast to nucleus signaling are still poorly understood. An intermediate of the plastid isoprenoid biosynthetic pathway (MEP), 2‐C‐methyl‐D‐erythritol‐2,4‐cyclopyrophosphate (MEcPP), has been shown to function as an inter‐organelle signal. Exogenous application of MEcPP or accumulation of this metabolite in Arabidopsis mutant plants (ceh1) results in induction of specific nuclear stress‐responsive genes. It has also been demonstrated that MEcPP accumulation potentiates the endoplasmic reticulum unfolded protein response, which is a critical component of stress adaptive responses. MEcPP accumulates in plants during environmental stress and/or physiological processes including high‐light, day‐night transitions, wounding, exposure to herbicides, and high‐temperature. It is well established that signaling events in plants involve the ubiquitin proteasome system (UPS). Plant hormones such as jasmonic acid, auxin and abscisic acid all rely on the UPS pathway for signal transduction. We have found that accumulation of MEcPP results in increased levels of ubiquitylation, raising the possibility of cross‐talk between the UPS and MEcPP in signal transduction processes. To address this possibility, we constructed Arabidopsis plants that accumulate high levels of MEcPP after induction and used a proteomics approach to detect MEcPP‐dependent ubiquitylation targets. This has identified 169 candidate proteins with increased ubiquitylation upon MEcPP induction. The results suggest that MEcPP signaling could be involved in reducing the activity of central metabolism and UPS‐mediated protein turnover. Additional experiments are being conducted to identify the ubiquitin E3 ligases activated by MEcPP signaling, which could be important targets for crop improvement and biotechnology.

Support or Funding Information

NIH, NSF
Transition State Mimic of Intrinsic Hydrolysis in Ras GTPase
Authors: Ortiz Alicia Yvette
Published: June 2021

Ras GTPases are involved in signal transduction pathways that control fundamental cellular processes such as proliferation, cycling, survival, and apoptosis. Ras functions via an on/off switch mechanism, where Ras is active in downstream signaling when bound to GTP and inactive upon GTP hydrolysis to GDP. Our lab discovered an allosteric site that is proposed to interact with the membrane, where binding in this allosteric site promotes ordering of the switch II region, favoring a conformation conducive to hydrolysis of GTP to GDP. When Ca2+ and acetate bind at this site in Ras crystals there is a disorder to order transition in switch II, positioning catalytic residues in place for hydrolysis. Interestingly, mutations of R97 to bulky aliphatic residues, such as L and M, mimic this effect, increasing hydrolysis rate constants relative to wild type. We had previously shown that in the presence of AlF3 RasR97L‐GDP binds to the Ras binding domain of Raf (Raf‐RBD), mimicking the γ‐phosphate of GTP. Here we present gel filtration studies of the R97M‐GDP mutant in the presence of Raf and AlF3 showing complex formation. The fact that Raf‐RBD binds to the R97L and R97M mutants, but not to wild type Ras, suggests that in these mutants the conformation associated with hydrolysis is more populated than in the wild type. AlFx has been used extensively to visualize the transition state of the GAP‐catalyzed GTP hydrolysis on Ras and its homologues. We are currently working on obtaining crystals of the H‐RasR97M‐Raf‐AlFx complex as a transition state model to elucidate the mechanism of intrinsic hydrolysis in Ras.

Support or Funding Information

NSF MCB‐1517295
Application of a High‐Performance Liquid Chromatography Method for the Evaluation of Non‐Provitamin A Carotenoids
Authors: Titcomb Tyler James , Davis Christopher R. , Tanumihardjo Sherry A.
Published: June 2021

Biofortification of maize with provitamin A carotenoids is an emerging intervention for providing vitamin A to people where maize is a staple crop. Analyzing the effectiveness of biofortified maize adoption will be important in the coming years. We propose that serum carotenoid profiles will be ideal for this endeavor. The C30 HPLC column was developed specifically for carotenoid separations because the longer alkyl chains provide better separation of carotenoids and their respected isomers. Most types of maize that have been released also have enhanced concentrations of the xanthophyll carotenoids lutein and zeaxanthin. Due to the chemical similarity of lutein and zeaxanthin, the C30 column is ideal for analysis because it is capable of maintaining separation of these two non‐provitamin A carotenoids. A potential drawback of the C30 column is longer analytical time specifically for lycopene. When monitoring study subject low carotenoid diets during a human maize feeding trial, we propose that lycopene can be used as a qualitative measure of compliance due to the abundance of the carotenoid in the typical western diet and the absence of lycopene in maize. Here we show the adaptation of an established HPLC method (Howe & Tanumihardjo, 2006) to include the quantification of lycopene and its respective isomers with a run time of 52 minutes, including equilibration, while maintaining the separation of lutein and zeaxanthin. Thus, serum carotenoids analysis could be useful for both measuring the adoption of maize and compliance in controlled feeding studies.

Support or Funding Information

Supported by USDA Hatch WIS01804, Global Health Funds at UW‐Madison, and Harvest Plus breeding contract 5204.
The 2015 Dietary Guidelines for Americans: Adherence to Key Recommendations in Hispanic Females
Authors: Hannon Bridget , Villegas Elizabeth , Wiley Angela , Teran‐Garcia Margarita
Published: June 2021

The Dietary Guidelines for Americans (DGAs) are released by the United States Department of Agriculture and Department of Health and Human Services to encourage consumption of a healthy eating pattern. Key recommendations of the 2015 DGAs include limiting saturated fats and sugars, and increasing consumption of a variety of fruits and vegetables, low‐fat dairy, and whole grains. The Healthy Eating Index (HEI) is commonly used as a measure of adherence, but the current HEI does not reflect the newest DGAs. Here, we propose a new HEI to assess adherence (HEI‐A) to the 2015 DGAs in a cohort of Hispanic females, a group disproportionately affected by obesity and related comorbidities.

Fifty Hispanic females completed a semi‐quantitative food frequency questionnaire. Anthropometric measurements were also taken. Key recommendations from the 2015 DGAs for women were reviewed and an adherence index was derived from ten categories, each with a maximum score of ten. Total adherence was the sum of these 10 categories (max = 100). The HEI‐A is similar to the 2010 HEI, but reflects changes made in the 2015 DGAs.

The average adherence score was 44.49 (SD: 14.47, 95% CI: 40.14–48.83). High fruit and vegetable intake was significantly associated with high adherence score (p=0.001). Low intake of saturated fat was significantly correlated with higher HEI‐A (r=0.71, p=0.03). The category with the greatest adherence was reduction of added sugars, with a mean score of 5.81 (SD: 2.94) out of 10. Adequate consumption of fruits and vegetables had the lowest mean of 2.89 (SD: 3.53). HEI‐A was not correlated with body mass index or waist circumference, and there were no significant differences between normal weight, overweight, or obese individuals.

On average, participants were meeting fewer than half the recommendations of the 2015 Dietary Guidelines for Americans, regardless of weight status. Of note, the lowest adherence was in consumption of fruits and vegetables, but those individuals meeting this recommendation had overall greater HEI‐A scores. The DGAs are released to encourage healthy eating to prevent disease, and nutrition education tailored to Hispanics should continue to focus on emphasizing adherence to prevent obesity and related disease in this at‐risk population.

Support or Funding Information

This project was supported by Agriculture and Food Research Initiative Competitive Grant no. 2015‐68001‐23248 from the USDA National Institute of Food and Agriculture.
Detection of Mature Plant miRNA in Different Biological Matrix: Importance of Internal Standard and Validation of the Method
Authors: Huang Haiqiu , Roh Jamin , Davis Cindy D. , Wang Thomas T.Y.
Published: June 2021

MicroRNAs (miRNAs) ubiquitously exist in microorganisms, plants and animals, and appear to modulate a wide range of critical biological processes. However, no definitive conclusion has been reached regarding the uptake of exogenous dietary small RNAs into mammalian circulation and organs and cross‐kingdom regulation. One of the critical issues is our ability to assess and distinguish the origin of miRNAs. Although periodate oxidation has been used to differentiate mammalian and plant miRNAs, validation of treatment efficiency and inclusion of proper controls for this method were lacking in previous studies. This study aimed to address: 1) the efficiency of periodate treatment in plant or mammalian RNA matrices, and 2) the necessity of inclusion of internal controls. We designed and tested spike‐in synthetic miRNAs in various plant and mammalian matrices and showed that they can be used as control for the completion of periodate oxidation. We found that overloading the reaction system with high concentration of RNA resulted in incomplete oxidation of unmethylated miRNA. The abundant miRNAs from soy and corn were analyzed in the plasma, liver, and fecal samples of C57BL/6 mice fed with a corn and soy based chow diet using our improved methodology. We did not detect plant miRNAs in the mouse plasma or liver samples. In summary, an improved methodology was developed for plant miRNA detection that appears to work well in different sample matrices.

Support or Funding Information

U.S. Department of Agriculture appropriated fund #8040‐51530‐056‐00D Office of Dietary Supplements Interagency Reimbursable Agreement #8040‐51530‐056‐20‐I
Impact of Usual Intake of Added Sugars on Nutrient Adequacy: NHANES 2009–2012
Authors: Nicklas Theresa
Published: June 2021

The impact of usual intake (UI) of added sugars on nutrient adequacy in the US population was measured using NHANES 2009–2012 data of children (2–18 years; n=6,109) and adults (19+ years; n=10,697). Dietary intake data were obtained from 24‐hour dietary recall interviews using an Automated Multiple‐Pass Method. The National Cancer Institute (NCI) Method was used to estimate UI of added sugars and other nutrients. Individual UI of subjects 2–18 and 19+ years, were separated into six groups: 0<5, 5 to <10, 10 to <15, 15 to <20, 20 to <25, and ≥25% of energy as added sugars. Covariate adjusted regression coefficients were generated to examine the magnitude of the association between the percentages of the population below the EAR and added sugars intake. For most nutrients with an EAR (13/17 in children and 14/17 in adults) added sugars intake was not related (p>0.01) to nutrient adequacy. For those nutrients affected (primarily calcium (beta= 10.48; p=0.003) and vitamin E (beta=5.72; p= 0.003) for children and vitamins D (beta= 1.42; p= 0.001) and E (beta= 3.95; p= 0.008) for adults) the percentage of the population with inadequate intakes were high even in the lower added sugars groups. The point of inflection where micronutrient intakes appeared to be most apparent for these nutrients was between 20% – <25% of total energy from added sugars; regression analyses using four groups (0– <5, 5– <10, 10– <15, 15– <20 % energy as added sugars) did not show significant relationships with the nutrients studied. These results suggest that poor food choices independent, or only partially related to added sugars intake, may have a larger impact on nutrient adequacy rather than added sugars specifically. Future work might consider co‐modeling added sugars intake with energy intake using more sophisticated models becoming available.

Support or Funding Information

USDA/ARS through specific cooperative agreement 58‐6250‐6‐003 and from the USDA Hatch Project LAB 94209. Partial support was also received from the Corn Refiners Association.
Preterm Birth and Biomarkers of Environmental Enteric Dysfunction among Infants in Tanzania
Authors: Liu Enju , Manji Karim P , McDonald Christine M , Gosselin Kerri , Kisenge Rodrick , Fawzi Wafaie W , Gewirtz Andrew T , Duggan Christopher P
Published: June 2021

Objective

To examine the relationship between preterm birth and biomarkers of environmental enteric dysfunction (EED) among infants.

Methods

We performed a longitudinal study among a subset of Tanzanian children (n=590) who were enrolled in a micronutrient supplementation trial at age 6 weeks. Blood samples were collected at 6 weeks, 6 months, and 12 months to test for biomarkers of EED (antibodies to lipopolysaccharide (anti‐LPS) and flagellin (anti‐flagellin)). Longitudinal data analysis strategy (proc mixed in SAS) was used to examine the association between preterm birth and EED biomarkers. We adjusted for potential confounders including maternal age, maternal education, maternal middle arm circumference, daily food expenditure, household wealth, infant sex, and delivery by cesarean section. Tukey‐Kramer methods were used to adjust for multiple comparisons.

Results

56 (9.5%) infants were born preterm (defined as gestational age <37 weeks). Serum concentrations of all EED biomarkers increased over time (P trend<0.001). In multivariate analysis, at age 6 weeks, preterm infants had significantly higher serum concentrations of anti‐flagellin IgG (adjusted mean: 0.67 vs 0.49, p<0.01), anti‐flagellin IgA (0.45 vs 0.29, P<0.01), anti‐LPS IgG (1.05 vs. 0.78, P<0.01), anti‐LPS IgA (0.62 vs 0.42, p<0.01) compared to full‐term infants. At follow‐up (6 and 12 months of age), these differences did not persist (figure 1).

Conclusion

Tanzanian infants born at < 37 weeks gestational age had significantly higher serum concentrations of four biomarkers of EED at 6 weeks of age, compared to full term infants. These differences did not persist later in infancy. Our data suggest that preterm infants may be uniquely susceptible to EED, and that this gastrointestinal dysfunction may have implications for growth and health outcomes in infancy and later. More efforts should be made to identify maternal, environmental, and dietary determinants of EED biomarkers from pregnancy to early childhood.

Support or Funding Information

Support for this effort was provided jointly by NIH (grants R01 HD048969 and K24 DK104676) and the Feed the Future Innovation Lab for Nutrition which is funded by the United States Agency for International Development (USAID)
Evaluation of Fluorescence Microsphere Immunoassay for Antibody Detection to Rift Valley Fever Nucleocapsid Protein and Glycoproteins
Authors: Ragan Izabela , Faburay Bonto , McVey D Scott , Richt Juergen A , Davis A Sally , Rowland Raymond R , Wilson William C
Published: June 2021

Rift Valley Fever Virus (RVFV) is a zoonotic disease that infects ruminants including cattle, sheep, goats, camels and buffalo. There is a need to create a safe, rapid, and accurate assay that can simultaneously detect antibodies directed against multiple RVFV antigens. We describe the improvement and validation of a fluorescence microsphere immunoassay (FMIA) for the detection of IgG antibodies against the RVFV glycoproteins and the immunodominant nucleocapsid (N) protein. The purpose of this assay is to simultaneously screen and confirm sera from animals for positive or negative disease status. Well‐characterized vaccinated and experimentally infected sheep and calf sera were used for the evaluation of the assay. Recombinant viral proteins were produced then coupled to polystyrene magnetic beads for analysis using the Luminex MAGPIX system with xMAP technology. An unrelated viral antigen coupled control bead set was added to the reaction in order to account for non‐specific binding of antibodies to the antigen of the antigen‐bead complex. Median Fluorescence Intensity (MFI) results were converted to Sample/Positive ratios in order to standardize test results. Our results revealed highest MFI values for the detection of IgG antibodies against the RVFV N protein, indicating that this RVFV antigen could serve as a good candidate for a screening assay. The glycoprotein Gn target has been shown to differentiate vaccinated from non‐vaccinated animals in a candidate subunit vaccine formulation based on the RVFV Gn and Gc proteins. The FMIA demonstrated a high correlation (R2) of 0.91 when compared side by side with plaque reduction neutralization tests. The addition of further RVFV targets such as the non‐structural proteins NSs and NSm is currently under investigation. The results presented in this report demonstrate that FMIA provides a rapid and robust serological diagnostic tool for the detection of antibodies against RVFV. The targets developed in this assay will provide the basis for the development of a multiplex sero‐diagnostic assay system that can simultaneously screen for several ruminant diseases including transboundary animal diseases.

Support or Funding Information

This material is based upon work supported by the Kansas State NBAF Transition Funds, Kansas State University College of Veterinary Medicine, University of Pretoria Department of Veterinary Tropical Diseases, the USDA Agricultural Research project number 5430‐32000‐005‐00D and the U.S. Department of Homeland Security under Grant Award Number DHS‐2010‐ST‐061‐AG0001. The views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the U.S. Department of Homeland Security.
Controlling Hydrogen Sulfide concentrations via PDMS microfluidics for endothelial cell culture
Authors: Christoforidis Theodore , Driver Tom , Rehman Jalees , Eddington David T
Published: June 2021

BACKGROUND

Hydrogen Sulfide (H2S), along with carbon monoxide and nitric oxide, has been found to be one of the cell gasotransmitters affecting vascular cell function, blood vessel growth as well as modulating the potassium‐ATP channels . Delivery of consistent hydrogen sulfide levels to study its physiological effects has been a challenge because of the rapid degradation of the molecule and this represents an obstacle in the field. Current cell culture studies are implemented with hydrogen sulfide concentrations that are not stable with time as the donors used degrade with time.

PURPOSE

To develop a system that would allow controllable hydrogen sulfide concentrations for cell cultures.

METHODS

We developed a novel approach which delivers H2S via diffusion from microfluidic channels through a gas permeable membrane fabricated using PDMS soft lithography (Figure 1). The device consists of 3 different layers, the microfluidic channels, a 100μm thick PDMS membrane and a reservoir, where the cells can be seeded with appropriate amount of media. H2S molecules diffuse through the PDMS membrane to the cell culture reservoir. In this system, a defined mixture of sodium hydrogen sulfide (NaHS), used as a H2S donor, was injected through the microchannels using a syringe pump (Harvard Apparatus) . The detection of the H2S concentration was achieved using electrochemical sensors (Alphasense, Essex, UK). The electrical signal is acquired with a data acquisition system (NI‐9205, National Instruments, TX) using Labview.

RESULTS

It is shown that H2S concentration is dependent on the concentration of the solution of NaHS and the flow rate of the solution in the microchannels. In this way different concentrations of H2S can be obtained in a controllable way. Our microfluidic approach enables the study of H2S in the range of 0 – 4.2 ppm (0–123 μM) which corresponds to the physiological concentrations in the low μM range (0.5–120 μM) (figure 2 & 3) .

CONCLUSIONS

Studying the impact of hydrogen sulfide in cell cultures is not yet well understood. We provide a method to control hydrogen sulfide for cell cultures. To our knowledge there is no other in vitro model that hydrogen sulfide concentration can be controlled.

Support or Funding Information

National Science Foundation 1253060, DTE.
The mitohormetic response and an evaluation of a method for inducing oxidative damage
Authors: Zhang Yufeng , Humes Frances , Brasher Adam , Kavazis Andreas , Hood Wendy
Published: June 2021

It has been proposed that mitochondria display a biphasic response to reactive oxygen species (ROS) accumulation referred to as mitohormesis. Under mitohormesis, low levels of ROS stimulate protection against oxidative damage, whereas high levels result in the accumulation of oxidative damage. The mechanisms that underlie improved function following low levels of ROS production are poorly understood. We evaluated the changes in mitochondrial performance in house mice following X‐irradiation, which induces ROS production. Eight mice were maintained as unexposed controls and 8 mice were assigned to each of 5 groups that varied in time between x‐ray exposure and mitochondrial isolation, including 1 hour, 1, 4, 7, and 10 days after x‐ray. We measured mitochondrial respiratory function (RCR), ROS production (H2O2), and oxidative lipid damage (4‐HNE) in the liver and the skeletal muscle from both hind legs and liver. In liver, RCR showed a right skewed U‐shape curve in which day 1 and day 4 mice had significantly lower RCR than both non‐irradiation control, and all other x‐rayed mice. H2O2 and 4‐HNE in liver displayed inverse U‐shaped curves, with both peaking on day 4. Similar trends that were not significant were observe for RCR, H2O2 and 4‐HNE levels in muscle. These data provide evidence that mitochondria become damaged in response to x‐ray, but recover within one week of exposure. This represents the protective effect that ROS exposure has on mitochondrial function. Ongoing measurements of oxidative damage repair, mitophagy, mitochondrial apoptosis, and biogenesis will provide more comprehensive understanding of the mitohormetic response. The value of x‐ray in inducing oxidative damage in experimental studies will be discussed.

Support or Funding Information

This research was funded by US National Science Foundation grant 1453784
RNA‐seq Analysis of the Effects of Cold‐Acclimation and Freezing on the Hepatic Transcriptome in the Freeze‐Tolerant Cope's Gray Treefrog, Hyla chrysoscelis
Authors: do Amaral M. Clara F. , Frisbie James , Goldstein David L. , Krane Carissa
Published: June 2021

Cope's gray treefrog, Hyla chrysoscelis, is one of few freeze‐tolerant amphibians found in North America. This species is able to withstand freezing of its body fluids, partly by accumulating two cryoprotective compounds putatively synthesized by the liver: glycerol and glucose. Extracellular glycerol accumulates during cold acclimation, whereas somatic freezing triggers hepatic release of glucose, likely through glycogen catabolism. In this study we investigated how cold acclimation and freezing modulated hepatic gene expression in H. chrysoscelis. We hypothesized that pathways related to cryoprotectant production and stress tolerance would be upregulated to meet the physiological challenges encountered by these frogs during fall and winter. We generated a hepatic transcriptome using high‐throughput RNA sequencing and compared gene expression profiles among frogs that were warm‐acclimated, cold‐acclimated, and frozen. Sequences were annotated using Trinotate and Blast2GO, and the R package DESeq 2 was used to determine differential gene expression between treatments. We annotated approximately 34% of the transcriptome. Cold‐acclimated and frozen animals had more downregulated genes than upregulated. Contrary to expectation, expression of genes related to glycerol synthesis was unchanged from warm to cold conditions. Furthermore, glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) showed decreased expression in cold and frozen animals, suggesting a reduction in either gluconeogenic flux, glycolysis or both, which may impact cryoprotectant accumulation. On the other hand, glucose export from the liver may be promoted in both cold and frozen frogs as glucose‐6‐phosphatase (G6Pase) was upregulated in these conditions. However, glucose transporters 8 (GLUT8) and 10 (GLUT10), the sodium/glucose cotransporter 4 (SGLT4), and the glycerol channel aquaporin 9 (AQP9) were downregulated in frozen frogs, raising questions regarding the export of hepatic glucose and glycerol during freezing. Several genes involved in protein folding (e.g., heat shock proteins) and DNA repair were upregulated in cold and frozen frogs, although pro‐apoptosis genes were both up‐ and downregulated, whereas genes related to mitigating oxidative stress were downregulated in these groups. These results warrant further investigation of the different types of cellular insult that may be present in the liver during fall and winter. Our results suggest that hepatic genes are highly responsive to low temperatures. Furthermore, we found that control of cryoprotectant production and export, and of stress‐related gene expression, is in part accomplished by regulating transcription.

Support or Funding Information

Supported by NSF IOS‐1121457 to CMK and DLG, Schuellein Chair in the Biological Sciences to CMK, and Schuellein Chair Postdoctoral Fellowship to MCFA.
Bicarbonate‐Stimulated Soluble Adenylyl Cyclase Is an Acid‐Base Sensor Present in the Cell Cytoplasm and Nucleus of Elasmobranch Fishes
Authors: Roa Jinae N , Tresguerres Martin
Published: June 2021

Regulation of acid‐base stress (i.e. carbon dioxide [CO2], pH, and bicarbonate [HCO3−]) is essential for proper functioning of cells, organs, and whole‐animals; however, the mechanisms for sensing acid‐base stress are largely unknown in marine animals. One such sensing mechanism involves the evolutionarily conserved acid‐base sensor soluble adenylyl cyclase (sAC, adcy10), which is present and co‐expressed along with transmembrane adenylyl cyclases (tmACs, adcy1–9) in leopard shark and round ray acid‐base regulatory gill cells. Both sAC and tmACs produce the second messenger cyclic adenosine monophosphate (cAMP), but have different regulatory effects depending on species and tissue type. In isolated base‐secreting cells exposed to alkalosis, HCO3− activation of sAC led to translocation of the proton pump to the cell membrane, whereas forskolin activation of tmACs did not. Additionally, sAC is present in other shark tissues including the rectal gland, cornea, intestine, and white muscle where it likely regulates acid‐base status in response to tissue‐specific physiological acid‐base disturbances. Furthermore, sAC is present in the cell nucleus where it likely facilitates regulation of gene expression through protein kinase A (PKA) phosphorylation of target proteins.

Support or Funding Information

JNR is supported by the William Townsend Porter Pre‐doctoral Fellowship from the American Physiological Society. This research was supported by NIH Training Grant in Marine Biotechnology (GM067550) to JNR and NSF grant IOS 1354181 to MT
Role of an Abscisic Acid‐Activated Protein Kinase in Drought Response in Soybean Revealed by RNA‐Seq
Authors: Sah Saroj Kumar , Popescu George , Reddy K. Raja , Klink Vincent , Li Jiaxu
Published: June 2021

Glycine max (soybean) is the most important oilseed cereal crop, most widely grown in the world. It is the most important source of protein and oils for humans as well as for biodiesel production. Drought stress is the major environmental factor limiting the productivity of soybean. With the rapid growth of global population and environmental degradation, improving soybean yield is a crucial task to meet the human demand for food and energy. Soybean can survive drought stress if there is a robust and deep root system. Thus, there is a significant need for crop improvements that will increase stress tolerance. Abscisic acid is the essential hormone mediating abiotic stress responses in plants. We previously identified an abscisic acid‐activated protein kinase (AAPK) in broad bean and demonstrated that AAPK is a positive regulator that can enhance abscisic acid signaling. These results suggest that genetic engineering of the AAPK gene may have the potential to improve drought stress in crop plants. To this end, we have generated overexpression and RNAi lines of three AAPK homologous genes in soybean. We found an RNAi line of AAPK homologous gene a noticeable reduction in plant wilting in response to drought treatment. To understand the phenotype changes of this AAPK‐knockdown line, we conducted a genome‐wide transcriptomic analysis in roots of soybean at the early vegetative stage under drought stress. The analysis with an RNA‐Seq pipeline (using STAR aligner and edgeR analysis of differential gene expression) identified over 4000 gene transcripts that were differentially expressed as a response to drought stress in wild‐type samples and RNAi knockdown samples. Our ongoing study reveals the dynamic transcriptomic reconfiguration in soybean roots to acclimate drought stress and highlights the gene expression changes associated with signaling through AAPK. We expect that pathway analysis of the differentially expressed genes will reveal new signaling components associated with drought stress in soybean.

Support or Funding Information

This research was supported by MAFES (Mississippi Agricultural and Forestry Experiment Station) Special Research Initiative grants to Jiaxu Li and Vincent Klink. Saroj Sah is supported by a MAFES Director's Doctoral Fellowship awarded to Jiaxu Li and Raja Reddy. This material is based upon work that is supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, Hatch/Multi State project (Multistate No. NC1200; Project No. MIS‐153180) under Accession No. 232044. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily reflect the view of the U.S. Department of Agriculture.
Rosehip (Rosa canina) extracts prevent AKT and MAPK‐mediated cell proliferation in triple negative breast cancer cells
Authors: Cagle Patrice , Martin Patrick
Published: June 2021

Triple Negative Breast Cancer (TNBC) is an aggressive form of breast cancer, characterized by its lack of the human epidermal growth factor receptor‐2, the estrogen receptor, and the progesterone receptor. AKT and MAPK have been shown to promote cell proliferation and migration in triple negative breast cancer. Currently, the existing targeted therapy is of minimal benefit in TNBCs. Furthermore, adverse side effects and the emergence of drug‐resistant cancer cells are of great concern. Natural products have received growing interest in recent years as an alternative medicine with potential anti‐oncogenic properties. Rosehip extracts have been used as dietary supplements to relieve symptoms associated with gastrointestinal disorders and arthritis, and in our laboratory it has been shown to prevent cell proliferation in glioblastomas. This study investigated the efficacy of rosehip extracts in preventing proliferation of a triple negative breast cancer cell line (HCC1395). HCC1395 cells treated with rosehip extracts (1mg/mL–25ng/mL) demonstrated a significant decrease in cell proliferation. The observed decrease in cell proliferation was equal to or better than the decrease of cell proliferation observed when inhibitors of the MAPK (U0126, 10 μM) or AKT (LY294002, 20 μM) signaling pathways were utilized. Additionally, pretreatment of this cell line with rosehip extracts selectively decreased AKT, p70S6K, and MAPK phosphorylation suggesting these extracts prevent TNBC cell proliferation and migration by blocking the AKT and MAPK signaling mechanisms. Western blot analysis and apoptosis studies demonstrate that rosehip extracts inhibit cell proliferation without promoting apoptosis, but induce cell cycle arrest.

To investigate the potential clinical application of rosehip extracts we examined whether rosehip extracts could enhance the chemotherapeutic properties of Doxorubicin (20μM), a chemotherapeutic agent used to treat breast cancer. Rosehip extracts demonstrated a greater anti‐proliferative effect than Doxorubicin alone and is equally effective in combination with Doxorubicin. These data suggest that rosehip extracts are capable of decreasing cell proliferation in a triple negative breast cancer cell line by blocking the AKT and MAPK signaling pathways and by regulating the cell cycle. Moreover, rosehip extracts demonstrate a greater inhibition of cell proliferation, when given alone and combination with Doxorubicin. This investigation demonstrates that rosehip extracts may serve as either an alternative or complimentary treatment to current chemotherapeutic regimens for triple negative breast cancer.

Support or Funding Information

National Science Foundation Graduate Research Fellowship Program Grant No. (NSF 13‐085)
New formulations for fortified‐blended foods: the MFFAPP Tanzania efficacy trial
Authors: Delimont Nicole M , Alavi Sajid , Lindshield Brian
Published: June 2021

Background

Fortified‐blended foods (FBFs) are micronutrient fortified, partially precooked blends of cereals and pulses that are the most commonly distributed micronutrient‐fortified food aid globally. Along with reformulation to improve FBF quality, it has been suggested that alternative commodities like sorghum and cowpea be considered for FBF formulation due to their drought tolerance, and local and regional availability in food aid receiving regions.

Objectives

Our primary objective was to determine whether newly formulated, extruded corn, soy, sorghum and cowpea‐based FBFs would result in equivalent or better hemoglobin and anemia outcomes compared with CSB+, the most commonly distributed FBF by the United States Agency for International Development. Secondary outcomes included evaluation of anthropometric and z‐score changes in height, weight, and mid‐upper arm circumference among groups.

Methods

Twenty‐week, partially randomized cluster control trial located in the Mara region of Tanzania between February and July 2016. White sorghum cowpea (WSC‐1, WSC‐2), red sorghum‐cowpea (RSC), white sorghum‐soy (WSS), extruded corn‐soy blend (CSB14), or CSB+ were provided to 2186 children divided into two age groups (6–23 and 24–53 months) in seven clusters. A negative control received no FBF until study end. At 0, 10, and 20 weeks, health questionnaires, hemoglobin, and anthropometric measurements were collected. Anemia prevalence, height, weight, MUAC, WAZ, LAZ, and WHZ were calculated for each cluster at each time point. Differences in baseline socioeconomic factors, food intake and unadjusted outcomes were analyzed with SAS. Absolute anemia risk reduction was calculated for all FBFs and control compared to CSB+. Improvement and deterioration in HAZ and LAZ were also analyzed.

Results

Newly formulated FBFs were non‐inferior, or superior, to CSB+ in all outcome measures. At end line, there were significant absolute anemia risk reductions in all newly formulated FBFs compared to CSB+ in at least one age group; CSB14 and WSC‐1 anemia prevalence was significantly reduced in both age groups. In both groups, there were significant improvements in control, WSC‐2, and WSS consuming groups' HAZ scores from baseline to end line, and more children's HAZ scores improved than deteriorated compared to control in all FBFs groups.

Conclusion

Results suggest that sorghum and cowpea may be suitable alternatives to corn‐soy based FBFs. Socioeconomic and health factors will be analyzed in adjusted models for all outcomes.

Support or Funding Information

United States Department of Agriculture (USDA) Foreign Agricultural Service under the Micronutrient Fortified Food Aid Products Pilot (MFFAPP) program, contract number #FFE‐621‐2012/033‐00.
Content Validity of the Abbreviated Women's Empowerment in Agriculture Index (A‐WEAI) in Ethiopia: A Mixed Methods Approach
Authors: Min‐Barron Marion , Coates Jennifer , Ghosh Shibani , Rogers Beatrice , Maluccio John
Published: June 2021

The conceptual pathway between agriculture and nutrition through the vehicle of women's empowerment has garnered much attention as a means to reducing global malnutrition. Until recently, understanding this complex pathway was particularly challenging given that there was no widely accepted approach to measuring women's empowerment. In 2012, Feed the Future launched the Women's Empowerment in Agriculture Index (WEAI), which measures the empowerment, inclusion and agency of women within the agricultural sector. This research study assessed the internal validity of the Abbreviated Women's Empowerment in Agriculture Index (A‐WEAI), a second iteration of the WEAI, within the context of Ethiopian smallholder farming households. Through three phases of data collection, this study identified salient aspects of Ethiopian culture and social gender norms that influence the reliability and internal validity of the A‐WEAI as an indicator of Ethiopian women's empowerment. The first phase entailed 24 focus groups, which collected qualitative data on Ethiopian agricultural households' gender norms and understanding of the term ‘women's empowerment’. Within the second phase, 300 households responded to the quantitative A‐WEAI survey. These results were used to test content validity through principal component analysis and internal reliability through Cronbach's alpha. The last phase of data collection further assessed content validity through an expert panel survey that was used to construct a Content Validity Index (CVI). Results indicate that there are distinct Ethiopian gender norms in relation to agricultural engagement. Women most commonly defined ‘empowerment’ to mean ‘decision‐making’ and cited relationships to others (spouses, children, extended family, etc) as a strong influence on perceived levels of empowerment. To the best of our knowledge, neither the WEAI nor A‐WEAI has been assessed for content validity in any setting. Results from this study hold great significance as they contribute to understanding, for the first time, the content validity of the scale in general. This study also provides insights into the A‐WEAI's functioning in Ethiopia. Future research is needed to identify specific appropriate changes to the A‐WEAI such that women's empowerment is measured in an accurate, valid (both internally and externally) and reliable manner and thus useful in guiding policy.

Support or Funding Information

This research work was made possible by the support of the American people through the United States Agency for International Development (USAID) under Agreement No. AID‐663‐A‐11‐000‐17. The contents of this document are the sole responsibility of the researcher & do not necessarily reflect the views of USAID or the United States Government.