bluuebunny/crossref_metadata_2025 huggingface dataset:
Opioid effects on respiration and analgesia in turtles
Authors: Johnson Stephen M. , Sladky Kurt K.
Published: June 2021

A goal in veterinary medicine is to provide pain relief without respiratory depression. In non‐human mammals, several drug combinations provide analgesia and reverse opioid‐dependent respiratory depression. For reptiles, little is known with respect to opioid drug effects on respiration and nociception. Thus, breathing and responsiveness to noxious hindlimb thermal stimuli were measured in adult turtles before and after administration of drugs that activate specific opioid receptor subtypes or clinically‐relevant opioid drugs. Activation of mu‐ (MOR) or delta‐opioid (DOR) receptors decreased breathing by decreasing breath frequency; kappa‐opioid (KOR) receptor activation increased tidal volume. Activation of MOR (but not DOR or KOR) receptors increased hindlimb thermal withdrawal latencies. MOR agonists, such as morphine, methadone, and tramadol, produced analgesia, but also caused respiratory depression. In contrast, analgesic drugs, such as butorphanol (KOR agonist, MOR agonist/antagonist) and meperidine (MOR agonist) had no effect on nociception. These results show that not all analgesic drugs (that work in mammals) produce antinociception in turtles. Future studies will test (mammalian‐derived) drug combinations that produce opioid‐dependent analgesia and reverse respiratory depression in turtles. (Supported by NSF IOB 0517302, Morris Animal Foundation)
Why are there no freshwater, longhorn sculpin (Myoxocephalus octodecimspinosus)? Effects of low environmental salinity on gill ion transporter expression
Authors: Hyndman Kelly Anne , Evans David H.
Published: June 2021

The genus Myoxocephalus contains 10 seawater (SW) and 3 freshwater (FW) species; the FW sculpin separated from the SW sculpin ~2–5 mya. The SW longhorn sculpin (M. octodecimspinosus) can tolerate days in low salinity but has never been found in FW. The purpose of our study was to determine why this fish is incapable of surviving in low salinities. The teleost gill contains mitochondrion‐rich cells that are the main site of ion balance, and these cells contain high densities of ion transporters such as Na+, K+‐ATPase (NKA), Na+‐K+‐2Cl−cotransporter (NKCC), and the Cl− channel, CFTR. SW teleosts generally have higher abundances of these transporters than FW teleosts. We hypothesized that sculpin can not survive low salinities because they can not properly regulate ion transporter density. We first sequenced sculpin gill cDNA for NKA, NKCC and CFTR. Next, sculpin were acclimated to 100% (control), 20%, or 10% SW for 24 and 72 hr. Plasma osmolality, Na+, K+ and Cl− did not differ between 100% and 20% SW but were significantly lower in the 10% SW sculpin at 24 and 72 hr. Gill NKCC and CFTR mRNA levels did not differ among treatments. Conversely, NKA levels were significantly higher after 72 hr in 20% or 10% SW, although there were no obvious changes in immunolocalization of the transporters in the gill or changes in protein levels (Western and dot blots). We conclude that the longhorn sculpin is incapable of surviving in low salinities because it can not regulate ion transporter densities to maintain proper ion balance. It may be that variation in this ability initially led to the invasion of FW by other sculpin species. This work was funded by NSF IOB‐0519579 to DHE.
Aquaporin and glyceroporin mRNA and protein expression in maturing Hyla chrysoscelis
Authors: Wysong Robert , Goldstein David L.
Published: June 2021

Gray treefrogs Hyla chrysoscelis express aquaporins (HC1 and HC2) and glyceroporins (HC3) in tissue‐ and thermal‐specific patterns. These expression patterns likely facilitate water and glycerol redistribution during times of osmoregulatory challenge like dehydration or freezing. We hypothesized that expression of aquaporins would also change during growth and the transition from aquatic to terrestrial life. To test this, real time quantitative PCR and Western blotting were used to characterize the temporal expression of the three aquaporins, using beta actin as a baseline. At the earliest tadpole stage tested, Gosner developmental stage 24, mRNA expression was detectable for all three aquaporins in body tissue extracts. We tested ventral skin separately for expression of AQP‐HC2, which remained undetectable by Gosner stage 32, though it is present in adult frogs. Further experiments are underway to localize expression of these proteins to specific tissues using immunohistochemistry. Supported by NSF IOB‐0517301.
Developmental expression of carbonic anyhdrase II in the extraembryonic membranes of the corn snake, Pantherophis guttatus
Authors: Khambaty Maleka , Stewart James R , Ecay Tom W
Published: June 2021

The eggshell provides 28% of the calcium in a hatchling corn snake, with the remainder coming from yolk. The chorioallantois contributes to calcium homeostasis during embryogenesis by mediating the transport of shell calcium to the embryo. Our objective is to understand how the embryo regulates dissolution of mineralized shell calcium and its transport during development. We hypothesize that cells of the chorioallantois secrete acid onto the eggshell thereby dissolving calcium carbonate crystals. Acid production is catalyzed by carbonic anhydrase II (CA II). Immunoblotting demonstrates an increase in CAII expression throughout development in the chorioallantois but no detectable expression in the yolk sack. Increased CAII expression is coincident with increased calbindin‐D28K expression, a marker for calcium transport. Histochemical staining identifies CA positive cells at the outer surface of the chorioallantois adjacent to the eggshell. CAII and calbindin‐D28K immunohistochemisty are being used to determine if acid secretion and calcium transport occurs in the same or different cells of the chorioallantois. (Supported by the NSF and an APS Undergraduate Summer Research Fellowship.)
Comparative immunolocalization of Na+/K+‐ATPase and Na+/K+/2Cl− cotransporter in the kidneys of freshwater and marine snakes
Authors: Babonis Leslie Susann , Lillywhite Harvey B. , Evans David H.
Published: June 2021

In contrast with the marine sea snakes, watersnakes in the genus Nerodia are not known to have functional salt glands. Despite this physiological difference, at least two species of watersnake are known to inhabit marine environments; the remaining members of this genus occupy freshwater habitats. The mechanism by which marine watersnakes regulate ion balance without functional salt glands is unknown. In this study, we compared the cellular anatomy of kidneys from two species of watersnake, Nerodia fasciata (freshwater) and N. clarkii (marine), and one species of sea snake, Laticauda semifasciata (marine). Specifically, we examined the localization of Na+/K+‐ATPase (NKA) and Na+/K+/2Cl− cotransporter (NKCC), two proteins that are known to regulate membrane potential and drive salt secretion in all vertebrate secretory cells examined to date. Using histology and immunohistochemistry, we localized NKA and NKCC to the basolateral membranes of the distal tubules in all three species of snake. These results are consistent with the localization of these proteins in other secretory tissues such as the gills of teleost fishes and the salt glands of marine elasmobranchs, birds, and reptiles, and suggest a potential role for ion regulation at the level of the kidney. This research was funded by the National Geographic Society (8058‐06 to HBL) and the National Science Foundation (IOB‐0519579 to DHE).
Progressive exercise training protects bone marrow stem cells from radiation‐induced damage
Authors: De Lisio Michael , Phan Nghi , Boreham Doug , Parise Gianni
Published: June 2021

Exercise training is known to induce an adaptive response in numerous tissues, however, the effects of exercise training on bone marrow stem cells (BMSC) is unknown. The purpose of this study was to determine if exercise training produced adaptations in BMSC and if this adaptive response could protect against subsequent high levels of ROS. C57Bl/6 mice were divided into the following groups (n=6 per group): treadmill running (EX), treadmill running and low dose radiation (ExLDR), and control (CON). Following 10 weeks of intervention half the mice in each group were exposed to a high dose radiation (HDR) challenge. Exercise training did not affect the basal number of double strand breaks (DSB) as determined by Gamma H2AX foci, but resulted in significantly fewer DSB in response to HDR, in vitro. Furthermore, exercise training significantly decreased both the basal number of micronucleated reticulocytes (MN‐RET) as well as the number of MN‐RET in response to HDR, in vivo. Interestingly, exercise was able to prevent the increase in basal MN‐RET in the mice exposed to 10 weeks of LDR. In conclusion, progressive exercise training was sufficient to protect BMSC from high doses of radiation. This research was funded by US DOE, Low Dose Research Program (DE‐FG02‐07ER64343) and NSERC.
Tubuloglomerular feedback signal transduction in a model of a compliant thick ascending limb
Authors: Layton Harold E , Moore Leon C , Layton Anita T
Published: June 2021

We used a mathematical model to predict the impact of tubular compliance on tubuloglomerular feedback (TGF) signal transduction in the thick acending limb (TAL). In several previous studies, we used a mathematical model that represented the TAL as a rigid tube. That model predicts that TGF signal transduction by the TAL is a generator of nonlinearities: if a sinusoidal oscillation is added to constant intratubular fluid flow, the NaCl concentration alongside the macula densa will be nonsinusoidal owing to an accumulation of harmonics. We have hypothesized that complexity found in power spectra based on in vivo time series of key TGF variables arises in part from those harmonics and that nonlinearities in TGF‐mediated oscillations may result in increased NaCl delivery to the distal nephron. To address the concern that a more realistic TAL would damp harmonics, we have conducted simulations in a model TAL that has compliant walls and thus a tubular radius that depends on transmural pressure. These simulations predict that compliant TAL walls do not damp, but instead, intensify the harmonics.

This research supported in part by NSF grant DMS‐0715021 and NIH grant DK‐42091.
Kinetics of promoter escape varies as a function of KCl concentration
Authors: Karki Sophiya , Shrestha Elina , Aye‐Han Nwe‐Nwe , Hsu Lilian M
Published: June 2021

The efficiency of promoter escape in E. coli transcription initiation is dependent on two factors: 1) the rate of escape, and 2) the extent of RNA polymerase (RNAP) partitioning into escape‐competent open complexes. Both parameters can be obtained from a single cycle assay performed under RNAP‐limiting conditions. For T5 N25 and N25anti promoters, these two factors are governed by the initial transcribed sequence (ITS). N25 and N25anti promoters differ only in +3 to +20 region of the ITS, but exhibit half‐lives of ∼3 min and ∼42 min, respectively, for full‐length RNA synthesis. Interestingly, the slower escaping N25anti promoter forms a higher fraction of productive open complexes and yields higher levels of productive RNA than N25; this result was unexpected. The above studies were performed in 200 mM KCl solution. We next examined the effect of KCl concentration and found that lowering [KCl] from 200 – 10 mM increased the rate of escape for N25 while also raising its productive fraction. For N25anti, the escape rate remained the same while lower [KCl] brought about higher productive synthesis. We conclude that KCl concentration affects the open complex formation and partitioning similarly in both promoters, but influences their open complex collapse and escape differently, confirming that the rate of promoter escape is ITS‐sequence dependent. Supported by an NSF grant (RUI‐0418316) to L. M. Hsu.
Characterization of the functional domains of High Mobility Group A1 (HMGA1)
Authors: Pace Kelly , Sumter Takita Felder
Published: June 2021

The High Mobility Group A1 (HMGA1) gene encodes for two protein isoforms, HMGA1a and HMGA1b, produced by alternative splicing of hmga1. Expression of HMGA1 causes cell growth and division, however, when overexpressed HMGA1 is implicated in transformation and metastasis. HMGA1 acts by binding to AT rich regions of the minor grooves of DNA, but its specific mechanism of initiating neoplastic transformation is still unknown. To study this, we have focused on the structural components of HMGA1, which has three AT hook DNA binding domains. We are examining how deletions of one or more of these binding domains affect the ability of HMGA1 to cause transformation. Previous studies by our lab identify the second and third binding domains are important regions for transformation. In order to further analyze the domains, we characterized a new construct which allows inducible expression of the protein. The construct produces HMGA1 fused to an estrogen receptor subunit. When cells expressing this protein are treated with an estrogen derivative, 4‐hydroxytamoxifen, HMGA1 is translocated into the nucleus where it is active. In addition, induction of HMGA1‐ER expression promotes the transformed phenotype. This construct should be useful in future characterization studies of the AT hook DNA binding domains of HMGA1. This research is supported by grants from the NIH(P20RR04006) and NSF(0542242).
DmSNAPc domains for subunit assembly and DNA binding
Authors: Hung Ko‐Hsuan , Titus Mitchell , Chiang Shu‐Chi , Stumph William E.
Published: June 2021

The small nuclear RNA activating protein complex (SNAPc) is the major unique transcription factor required for transcription of genes coding for small nuclear RNAs (snRNAs). In the fruit fly Drosophila melanogaster, DmSNAPc contains three distinct subunits (DmSNAP190, DmSNAP50, and DmSNAP43) that form a complex before binding to an snRNA gene promoter. We have used mutational analysis to identify domains within each subunit of DmSNAPc that are required for complex formation with the other two subunits in vivo. Also, we mapped domains in each subunit that are required for the DNA‐binding activity of DmSNAPc. We have found that the most evolutionarily conserved regions of the proteins are involved in SNAP complex assembly. Nevertheless, we found that domains outside of the conserved regions are also important for the DNA binding activity of DmSNAPc, even though they are not required for subunit assembly. Comparing our findings with published results in the human system indicates not only many important similarities but also significant differences in this ancient though rapidly evolving system. This work is supported by National Science Foundation grants MCB‐0131151 and MCB‐0641350 and in part by the California Metabolic Research Foundation. M. T. is a recipient of an Arne N. Wick Pre‐doctoral Research Fellowship from the California Metabolic Research Foundation.
The Mechanism of Zinc Inhibition of Glutamate Dehydrogenase Involves Subunit Communication
Authors: Sinanan Leander , Bell Ellis
Published: June 2021

Zinc is a potent inhibitor of higher eukaryotic glutamate dehydrogenases. The mechanism of inhibition has previously been investigated using initial rate kinetic studies with either the dicarboxylic amino acid glutamate or the mono carboxylic alternative substrate norvaline. With glutamate zinc potently inhibits with the apparent affinity for zinc decreasing as the glutamate concentration decreases. With norvaline, no inhibition is seen. The goals of the current study were to quantitate the zinc binding, identify potential binding sites and determine whether or not zinc binding may be a] close to one of the three tryptophans in the protein, and b] induce conformational effects in the protein. Using the zinc sensitive chromophore 4‐par it is shown that zinc binds to glutamate dehydrogenase with a 1:1 stoichiometry with respect to polypeptide chains. Using tryptophan fluorescence spectroscopy it appears that zinc affects the most hydrophobic of the three tryptophans in the protein. Examination of the three dimensional structure of the enzyme raises the possibility that zinc binds at the subunit interface in the “twisty tie” region of the molecule. This is consistent with both the location of the most hydrophobic tryptophan and the fact that zinc appears to inhibit by disrupting subunit interactions necessary for full activity with glutamate as substrate.

Supported by NSF grant MCB 0448905 to EB
Comparison of the Endocytic Trafficking of Digestible and Indigestible Substances in Dictyostelium Amoeba
Authors: Giorgione Jennifer R. , Clarke Margaret
Published: June 2021

Most endocytic trafficking studies in both Dictyostelium and mammalian cells have used latex beads as the phagocytic substrate. Here, we have compared the trafficking of latex beads to that of digestible particles (bacteria and yeast). Differences were found for early phagosomes. PHcrac‐GFP binds to membranes enriched in PI(3,4,5)P3 and PI(3,4)P2, phosphoinositides present in the membrane of new phagosomes. During uptake of bacteria or yeast, PHcrac‐GFP always labeled the nascent phagosome and faded shortly after it sealed. However, bead‐containing phagosomes were much more variable. Uptake occurred with or without PHcrac labeling, and, when present, the label often persisted for many minutes. These differences suggest that the earliest trafficking steps are influenced by the contents of the phagosome. However, later steps of the pathway appeared to be similar. We looked at transport of phagosomes along microtubules and fusion with acidic endosomes, acquisition of the vacuolar‐ATPase and its loss before exocytosis, and transfer of vacuolin B from a phagosome membrane to the plasma membrane upon exocytosis. None of these processes seemed to be dependent upon the contents of the phagosome. We conclude that care must be taken when substituting latex beads for physiological substances in studies of endocytic trafficking, especially in the early stages of the pathway. Supported by the NSF.
Alpha‐2A adrenergic receptor activation inhibits rat hippocampal CA3 network activity
Authors: Pribula Jacquline A , Boese Sarah , Xu Ke , Nelson Brian , Goldenstein Brianna , O'Shea Lorraine , O'Brien Jasmine , Davis Kylie , Laverdure Floyd , Schulte Christina , Green Kristan , Schlosser Danielle , Luger Elizabeth , Lichter Jessica , Jurgens Chris , Porter James , Doze Van
Published: June 2021

Norepinephrine (NE) has potent antiepileptic properties, the pharmacology of which is unclear. The hippocampal CA3 region is vulnerable to over‐excitation (epileptiform burst activity). When GABAergic inhibition is blocked, NE reduces epileptiform activity through alpha‐2 adrenergic receptor (α2 AR) activation on pyramidal cells. We investigated which α2 AR subtype(s) mediate this effect. α2 AR mRNA expression using RT‐PCR in the CA3 region suggested that α2A AR subtype predominates relative to α2C AR and no α2B AR. Using field potential recordings in hippocampal slices we tested CA3 epileptiform activity. With a beta AR blockade, concentration‐response curves for AR agonists suggest that α2A ARs mediate CA3 epileptiform activity inhibition. Equilibrium dissociation constants (Kb) of selective alpha AR antagonists were determined to confirm the specific α2 AR subtype involved. Kb values correlated best with the α2A, but not the α2B and α2C AR subtypes. The results show that under impaired GABAergic inhibition, activation of α2A ARs is primarily responsible for antiepileptic action of NE. These findings increase our understanding of the role NE plays in attenuating epileptogenesis, and may aid the development of a subtype‐selective α2 AR agonist‐based strategy for treating seizures. Supported by NSF ND EPSCoR, NSF CAREER, NSF REU Site, NSF RET, NIH INBRE, EF, APS Explorations Program for Native Americans.
Effect of cigarette smoke exposure on the binding characteristics of dopamine receptors and transporter in guinea pig brain
Authors: Miller Leah , Mukherjee Shyamali , Das Salil K
Published: June 2021

The dopamine receptors play an important role in the regulation of brain functions such as memory, mood, movement and behavior. These brain functions are lost in neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD). Several epidemiological studies suggest that there is a neuroprotective association between cigarette smoking and various neurological disorders (i.e. AD, PD). In the present study, we examined the effect of cigarette smoke exposure on the binding characteristics of dopamine receptors (D1 and D2) as well as the dopamine transporter (DAT) in a guinea pig model of cigarette smoke exposure. Three‐week‐old guinea pigs were subjected to mainstream (MS) or sham (SH) smoke exposure, generated twice daily from three cigarettes for approximately 7 weeks. The midbrain tissue samples were collected and the binding characteristics of D1 and D2 receptors as well as DAT were analyzed by radioligand binding assay. Smoke exposure caused a significant increase in the binding capacity of D1 receptor and DAT; whereas it caused a significant decrease in the binding capacity of D2 receptors. No significant effect of smoking was noticed on the affinity of any of these parameters. Thus, the increase in the binding capacity of DAT is in line with the expected increase in the dopamine turnover by smoke exposure. (Supported by U.S. Army grant DAMD 17‐03‐2‐ and FAMRI Clinical Innovator Award)
Investigating the role of the eukaryotic elongation factors 1B‐α (1, 2) and eEF1B‐β (1, 2) from Arabidopsis thaliana in plant thermotolerance
Authors: Paul Megan Rose , Basha Eman , Vierling Elizabeth
Published: June 2021

All organisms respond to heat stress by producing heat shock proteins (HSPs). The small HSPs (sHSPs) are a class of chaperones thought to prevent irreversible heat denaturation of other proteins and to facilitate refolding during recovery. In higher plants, sHSPs represent a major component of the response to heat stress. To understand the mechanism of protection by sHSPs, we have sought to identify substrates of cytosolic class I sHSPs in the model plant Arabidopsis thaliana. Putative substrates were identified as associated with sHSPs in vivo during heat stress. Among the proteins identified were several of the eukaryotic translation elongation factors (eEFs). Four of these, eEF1B‐α (1, 2) and eEF1B‐β (1, 2), have been selected to be investigated further. They are required for GDP exchange from eEF1A, a GTPase which delivers the tRNA to the ribosome. To study the interaction of these factors with, and their protection by sHSPs, we are purifying these eEFs. Recombinant proteins will be used to make antibodies to study interactions of sHSPs and these factors in vivo. The proteins will be used to investigate the mechanism by which the sHSPs protect these eEFs in vitro. We have also obtained T‐DNA insertion lines of these genes to examine their importance in plant thermotolerance.

Project funding was provided by USDA‐NRICGP Grant 351001485 and NSF Grant IBN‐0213128 to EV and HHMI Grant 52005889 to the University of Arizona.
Control materials for validating measurement of vitamin D in key foods for the USDA National Food and Nutrient Analysis Program (NFNAP)
Authors: Holden Joanne M , Byrdwell William Craig , Exler Jacob , Harnly James , Hollick Michael , Hollis Bruce , Horst Ronald L , Patterson Kristine , Phillips Katherine , Wolf Wayne
Published: June 2021

Data for vitamin D in the National Nutrient Database for Standard Reference are being updated. High priority foods including fish and vitamin D fortified orange juice, breakfast cereals, milk, American cheese, and yogurt were sampled (n=446) according to a nationwide plan, to be analyzed by qualified laboratories. A lack of certified reference materials required development of control materials to ensure accurate measurements. Matrix‐specific food homogenates (e.g. salmon, orange juice) were prepared and analyzed by six laboratories experienced in determining Vitamin D. Initial results showed wide disparity among the laboratories (CV = 26–46%). Subsequent recovery studies, mass spectrometric analysis, verification of standards, optimization of extraction solvents resulted in reliable values. The three labs chosen for future analyses obtained statistically similar results. These data were used to assign mean values and tolerance limits for four of the control materials. Due to inconsistent data for salmon, further work is required to validate those results.

This research was supported by USDA, NIH, and the Beverage Institute for Health & Wellness (Coca‐Cola).
Despite the health burden, sodium intakes remain unchanged
Authors: Moshfegh Alanna , Steinfeldt Lois , Goldman Joseph
Published: June 2021

Numerous groups have made recommendations regarding daily dietary sodium intake not to exceed 2300–2400 mg and have predicted impressive reductions in cardiovascular disease and related health measures if sodium intake were reduced. The purpose of this study was to determine mean daily sodium intakes (±SEM) for all individuals (from infants to elderly) and 12 gender/age groups from What We Eat In America (WWEIA), NHANES 2003–2004 (n=8893) and compare (p<.001) results with the 1994–1996, 1998 Continuing Survey of Food Intakes by Individuals (n=21159). Estimated sodium intakes were based on foods reported in one 24‐hour dietary recall and included sodium in foods naturally, from processing, and in cooking. Estimated daily sodium intake from WWEIA for all individuals was 3353±30 mg. For both males and females, 20–39 year olds had the highest sodium intakes at 4556±118 and 3163±71 mg, respectively, from WWEIA. Estimated daily sodium intakes for all individuals did not differ between the two survey periods of 1994–1996, 1998 and 2003–2004: 3285±30 vs. 3353±30 mg, respectively. There was also no significant change in sodium intakes for any gender/age group with the exception of females 20+ years, where intakes increased by 159 mg, from 2752±26 to 2911±38 mg. However, estimated daily sodium intakes/1000 kcal for all individuals decreased by 100 mg between the two survey periods: 1666±7 vs. 1566±10 mg/1000 kcal, respectively. Overall, sodium intake has remained relatively unchanged since the mid‐1990s, continuing to exceed maximum intake recommendations. Funding for this study was provided by USDA.
Early infant diet and ERP correlates of speech stimuli discrimination in 9 month old infants
Authors: Pivik R T , Jing H. , Gilchrist J. M. , Badger T. M.
Published: June 2021

Processing and discrimination of speech stimuli were examined during the initial period of weaning in infants enrolled in a longitudinal study of infant diet and development (the Beginnings Study). Event‐related potential measures (ERP; 128 sites) were used to compare the processing of speech stimuli in healthy 9‐month old, full‐term infants who were exclusively breast‐fed (BF, n = 60) with those fed milk‐ (MF, n = 59) or soy‐based formula (SF, n = 61) since 2 months of age. ERPs were recorded in awake infants to two syllables (/pa/ and /ba/; randomized 80%:20% occurrence) and analyzed using ANOVA procedures with post‐hoc t‐tests. Data are reported for responses during the first 600 ms post‐stimulus in central and anterior temporal cortical areas. Significant (p < .05) between‐syllable differences in amplitude (/ba/ > /pa/) and latency (/ba/ < /pa/) were observed in all groups and generally similar across groups. However, greater between‐syllable amplitude differences for the late N450 component in BF and MF relative to SF infants suggests more extensive language‐related processing in BF and MF groups at this time. Whether these response patterns reflect transient diet‐related variations in syllable processing or represent differences that influence later language development may be clarified as this longitudinal study progresses. (Supported by USDA CRIS 6251‐51000‐002‐03S)
Do parental feeding practices predict authoritative, authoritarian, and permissive parenting styles?
Authors: Hubbs‐Tait Laura , Kennedy Tay S. , Page Melanie C. , Topham Glade L. , Harrist Amanda W.
Published: June 2021

Study objective was to evaluate links of parenting styles to feeding practices. Participants were 239 parents of first‐grade children (134 boys; 105 girls) enrolled in rural public schools. Measures included parental responses to Encouraging and Modeling questionnaires and parental responses to Child Feeding Questionnaire (CFQ); parenting styles were measured by the Parenting Styles and Dimensions Questionnaire (PSDQ). Regression analyses revealed that feeding behaviors explained 21%, 15%, and 8% of the variance in authoritative, authoritarian, and permissive parenting, respectively. Hypothesis 1: Responsibility, restriction (negative), monitoring, and modeling were significantly related to authoritative style (p < .00001). Hypothesis 2: Restriction, pressure to eat, and monitoring (negative) were significantly related to authoritarian style (p < .00001). Hypothesis 3: Modeling (negative) and restriction were significantly related to permissive style (p < .001). We conclude that parental feeding practices with young children are linked to general parenting styles and successful interventions to change parental feeding practices should address underlying parenting styles. This research was supported by United States Department of Agriculture Grant 2004‐05545.
Do Americans eat more on weekends?
Authors: Rhodes Donna G. , Goldman Joseph D. , Moshfegh Alanna J.
Published: June 2021

Nationally representative one‐day dietary data from What We Eat In America, NHANES 2001–2004 were analyzed for differences in estimated nutrient intakes and eating patterns on weekends and weekdays. The USDA Automated Multiple Pass Method was used to collect the 24‐hour recall from adult, aged 20 years and older, men (n=4385) and non‐pregnant/lactating women (n=4240). Overall, energy intake increased on weekend days (Fri‐Sun) compared to weekdays (Mon‐Thurs) for males (p<0.001) and females (p<0.01). Mean energy intake (±SEM) for males was 2464 ± 38 kcal/d on weekdays and 2747 ± 29 kcal/d on weekend days. Energy intake for females was 1773 ± 22 kcal/d and 1856 ± 17 kcal/d for weekdays and weekend days, respectively. Although total fat intake increased on weekend days, the proportion of energy from fat was similar on weekdays and weekend days. The proportion of energy from alcohol increased, whereas the proportion of energy from carbohydrate decreased on weekend days. These changes were significant (p<0.01) for both genders. Differences were also observed for nutrient intakes by eating occasion. In general, American adults are eating more kilocalories on weekend days compared to weekdays; these observations highlight the need for obesity prevention strategies to include a focus on weekend eating behaviors. The results of this study also illustrate the importance of considering weekend/weekday effects in dietary assessment.

Funding source for this study is USDA.
Sorghum bran varieties differentially influence endogenous antioxidant enzymes to protect against oxidative stress during colon carcinogenesis
Authors: Lewis Jayme B. , Taddeo Stella S. , McDonough Cassandra M. , Rooney Lloyd W. , Carroll Raymond J. , Turner Nancy D.
Published: June 2021

We have shown that the number of aberrant crypts (AC) decreased in rats consuming black (29%, P < 0.04) and brown (47%, P < 0.006) sorghum diets when compared to a cellulose diet; this decrease was an inverse function of diet antioxidant activity (ABTS). Because of this, we evaluated the effect of these diets on endogenous enzymatic activities (SOD, CAT, and GPx) in the rat colon. Rats consumed diets containing 6% fiber from either cellulose or isolated bran from white, brown (contains tannins), or black (contains anthocyanins) sorghum (n=10/diet). Diets were fed for 10 wk, with two AOM injections (15 mg/kg BW) administered in wk 3 and 4. Total SOD activity increased (16%, P < 0.04) in rats fed black sorghum (79.0 U/mg protein) compared to all other diets. A similar, non‐significant, trend occurred in mitochondrial SOD. White sorghum increased (P < 0.02) CAT activity (122.2 U/mg protein) compared to the cellulose diet, and the black and brown sorghum diets were intermediate. All sorghum diets suppressed GPx activity relative to cellulose. As observed in colon tumors, elevated GPx activity may reflect greater oxidative stress, contributing to greater AC formation in cellulose rats. These data suggest that the suppression in AC formation resulted through the differential actions of the sorghum brans on endogenous and exogenous antioxidant activity. Funded by USDA 58‐5430‐5‐339 and NIEHS P30‐ES09106.
Chromatographic profiles of Ginkgo biloba leaves and selected products
Authors: Lin Longze , Chen Pei , Ozcan Mustafa , Harnly James
Published: June 2021

Ginkgo biloba leaves and their extracts are one of the most widely used herbal products in the world. Their flavonoids and terpene lactones are considered to be the main beneficial components. Previous studies have focused on specific components, or families of components, but a comprehensive study to identify all phenolic components is lacking. A method based on liquid chromatography separation and detection by diode array and electrospray ionization/mass spectrometry (LC‐DAD‐ESI/MS) was developed to obtain chromatographic profiles for the flavonoids and terpene lactones of Ginkgo biloba leaves. The method was used to identify 46 glycosylated flavonols and flavones, 3 free aglycones, catechin, 10 biflavones, 3,4‐dihydroxybenzoic acid, and 4 terpene lactones in aqueous methanol extracts of the leaf materials. The phenolics content of the Ginkgo biloba products were the same as the raw leaves, with the exception of the biflavones, which were only found in the raw leaves. This is the first report for more than 20 of the flavonoids found in Ginkgo biloba leaves.

This research was funded by USDA and the Office of Dietary Supplements at the National Institutes of Health.
Profiling Histidine Dipeptides in Plasma and Urine After Ingesting Beef, Chicken or Chicken Broth in Humans
Authors: Yeum Kyung‐Jin , Aldini Giancarlo , Rasmussen Helen , Carini Marina , Russell Robert M
Published: June 2021

Reactive carbonyl species (RCS), oxidation products of polyunsaturated fatty acids, protein & sugars, play a role in the etiology of certain chronic diseases. Our previous studies revealed that histidine‐dipeptides such as carnosine and anserine detoxify cytotoxic carbonyls such as 4‐hydroxy‐trans‐2‐nonenal & acrolein by forming unreactive adducts. In the current study, pharmacokinetics of histidine‐dipeptides has been determined after ingesting histidine‐dipeptides rich foods. Healthy women (n=4) went through 3 phases of one dose of either 150g beef (B), 150g chicken (C), or chicken broth (CB) from 150g chicken with >2 wks of wash out period between each phase. Blood samples were collected 0‐300 min and urine samples before & after (up to 7 hrs) ingesting the food and analyzed for histidine dipeptides using LC‐ESI‐MS/MS. Only a negligible amount of carnosine was detected in plasma after ingesting B, C or CB. However, plasma anserine concentration was significantly increased (p<0.05) to 2.72 ± 1.08 μmol/L at 100 min and 0.78 ± 0.18 μmol/L at 60 min after ingesting C and CB, respectively. Urinary carnosine and anserine were increased 13.8 & 13.7 fold after ingesting B and 14.8 & 243 fold after CB ingestion, respectively. Thus, dietary histidine dipeptides, which are rapidly hydrolyzed by carnosinase in plasma & excreted in minor fraction in urine, may act as RCS sequestering agents. (Supported by USDA 58‐1950‐7‐707)
Role of erythrocytes in platelet activation during exposure to pathophysiological shear stress
Authors: Kermode John C , Park Sang Won , Ladner Tammy , Zheng Qi , Burgreen Greg W , Majumdar Suvankar
Published: June 2021

Interaction of von Willebrand factor (VWF) with circulating blood platelets is the initial trigger for thrombosis in an arterial stenosis. Exposure of blood to a high shear stress promotes such interaction. These events have previously been studied in vitro under conditions where the platelets adhere to a VWF‐coated surface. Our approach assesses platelet activation in the absence of adhesion. Whole blood is perfused through polyetheretherketone (PEEK) tubing that includes an artificial stenosis, comprising a short (4 cm) section of narrow‐bore (130 μm) tubing. The pressure differential across the stenosis was measured with a pressure transducer. Platelet activation was evaluated from secretion of [14C]serotonin, and erythrocyte lysis from release of hemoglobin. The pressure drop across the stenosis matched the predictions for laminar flow without turbulence. Platelet activation rose progressively with increasing perfusion rate (2–12 ml/min). We examined the role of erythrocytes in platelet activation by adjusting the hematocrit of the perfused blood. Platelet activation was minimal (mean increment of 1.9% in serotonin secretion at 12 ml/min flow) when the hematocrit was low (30%), but substantial (increment of 15.5%) with a high hematocrit (60%). In contrast, changes in the platelet count did not affect the extent of platelet activation. [Supported by the National Science Foundation.]
Plasma kallikrein‐kinin system and endothelial cell activation
Authors: Shariat‐Madar Zia , Yang Jia , Osman Noah , Wilson Sean M
Published: June 2021

Plasma kallikrein‐kinin system (KKS) is activated upon binding to subendothelium or endothelium, leading to the reduction of the concentrations of plasma prekallikrein (PK), factor XII, and high molecular weight kininogen (HK). Upon binding, PK converts to kallikrein on HK bound to endothelium. Kallikrein then liberates bradykinin from HK to activate bradykinin B2‐ and bradykinin B1 receptors that mediates nitric oxide and prostacyclin formation. However, the nature of KKS activation and signaling on endothelium remains divisive. We determined KKS activation and Ca2+ signaling in Fluo‐4 (10 μM) loaded cultured endothelial cells and by performing in‐situ recordings of endoethlial cells in mouse pulmonary arteries using confocal laser microscopy techniques. Stimulation of endothelial cells with HK or the complex of HK‐PK increased [Ca2+]i in a majority but not all cells, suggesting the involvement of a distinct physiologic mechanism(s). HK as well as HK‐PK concentration and changes in [Ca2+]i correlated and were inter‐dependent. HK‐induced changes in [Ca2+]i was significantly lower than the changes triggered by the complex of HK‐PK in endothelial cells. The [Ca2+]i was unaltered when HK binding to endothelium was blocked. These results indicate that a novel KKS cell‐signaling pathway regulates endothelial function. Support from NSF and AHA.
The effect of cannabinoids on the uptake of 2‐deoxy‐D‐glucose by Caco‐2 cells
Authors: Gonçalves Pedro , Araújo João R. , Azevedo Isabel , Martel Fátima
Published: June 2021

The endogenous cannabinoid system plays a role in the regulation of energy homeostasis acting through central pathways, and its dysregulation may be implicated in the pathogenesis of obesity. The endogenous cannabinoid system is also present in peripheral tissues. The aim of this work was to investigate the effect of cannabinoids upon the intestinal absorption of glucose, by investigating the effect of cannabinoid receptor agonists and antagonists upon the apical uptake of 3H‐2‐deoxy‐D‐glucose (3H‐DG) by human intestinal epithelial Caco‐2 cells. Uptake of 1 μM3H‐DG was both cytochalasin B‐ and phloridzin‐sensitive (±50% inhibition observed with each of these drugs), and their effect was not cumulative. On the other hand, uptake of 20 mM 3H‐DG was partially inhibited by cytochalasin B (±20%) and phloridzin had no effect. We verified that neither the cannabinoid receptor agonists THC (1–10 μM), anandamide (0.1–10 μM) and CP 55,940 (5 nM‐1 μM), nor the specific CB‐1 and CB‐2 antagonists (AM251 (10‐500 nM) and AM630 (50 nM‐1 μM), respectively) had a significant effect upon 3H‐DG uptake by Caco‐2 cells. This was true for both uptake of the low and high concentration of 3H‐DG. So, we hypothesize that cannabinoids do not interfere with the GLUT2‐mediated intestinal apical uptake of glucose. Supported by FCT (PTDC/SAU‐FCF/67805/2006).
Adolescent girls with higher trunk fat and trunk‐to‐peripheral skinfold ratio reach menarche early
Authors: Vijayadeva Vinutha , Grove John , Novotny Rachel , LeMarchand Loic , Daida Yihe
Published: June 2021

The aim of this study is to determine whether the type of fat distribution predicts the age at which girls reach menarche. A group of 67 prepubertal girls of Asian, Caucasian, and mixed Eurasian ancestry identified from an HMO membership were examined to assess if fat distribution at baseline would affect age at reaching menarche. Girls were examined twice with a 2‐year interval, with 39 reaching menarche. Tanner stage was assessed by a nurse practitioner and height, weight, circumferences and skinfold thicknesses were measured by a standardized experienced staff. Cox regression analysis of time until menarche was used, adjusting for baseline age and proportion of Asian ancestry. Girls with higher body mass index reached menarche early (p = 0.0021). With adjustment for height, shorter time to reach menarche was associated with greater hip circumference (p = 0.0039), iliac skinfold thickness (p = 0.0109), and trunk‐to‐peripheral skinfold ratio (p = 0.0052) measured at baseline. The sum of subscapular and iliac skin fold thicknesses was significantly associated with age at menarche (p = 0.0274) but not the sum of two arm and two leg skinfold thicknesses (p = 0.2424). In conclusion girls with higher fat deposition in the trunk tend to reach menarche early in this cohort of adolescent girls.[Supported by USDA, Grant # 9900700].
How geometric, electrical and contractile alterations effect cardiac function in the failing heart
Authors: Kerckhoffs Roy , Mulligan Larry , Omens Jeffrey , McCulloch Andrew
Published: June 2021

In heart failure patients with left bundle branch block (LBBB) global and regional cardiac function is reduced.

The goal of this study was to investigate how geometric, electrical and contractile alterations as they occur in heart failure with LBBB contribute to changes in global and regional function, using a numerical cardiovascular model.

A 3D ventricular model was coupled to a closed circulation (with no mitral regurgitation). Cardiac cycles were simulated for all combinations of 4 altered input parameters (dilation, slower conduction, reduced peak fiber stress, longer fiber force twitch). Contributions of alterations and their interactions to cardiac global (stroke volume, SV) and regional function (CURE index of mechanical synchrony: 0<CURE<1) were calculated.

Dilation increased SV, reduced peak stress, decreased SV, and their interaction was important for a decrease in SV (figure) in heart failure. Slower conduction was less important for SV. CURE depended on interactions between slower conduction and dilation, but reduced peak stress played a minor role.

This study has been supported by Medtronic, UC Discovery Grant ITL06‐10159, NIH grants P41 RR08605 and HL32583, and NSF grant BES‐0506252.
The EKG of black bears (Ursus americanus) in hypothermia compared with that of humans
Authors: Buresh Christopher T , Folk G. Edgar , Dickson Eric W , Thrift Diana L
Published: June 2021

Hearts of hibernators can resist lethal arrhythmias seen in hypothermic non‐hibernators. We present data on the effects of hypothermia on hearts of large hibernators, black bears. Hypothermia is used in cardiac surgery and survivors of cardiac arrest, but can also be fatal, leading to arrhythmias such as ventricular fibrillation and asystole. We compare electrophysiologic changes the heart undergoes in hypothermia between black bears and humans. Specifically, we compare heart rate and QT interval (QTi) with core body temperature. The last part of the QTi is the time during which the heart electrically repolarizes and mechanically relaxes. During this time the heart is vulnerable to fibrillation. Animal data was obtained from radio capsules implanted in 3 black bears that were made progressively hypothermic. Human data came from published literature. Black bears and humans show a direct relationship between heart rate and body temperature. Both bears and humans developed J (Osborne) waves, the amplitude of which correlated with the degree of hypothermia. As heart rate and body temperature decrease, QTi increases. However, 2 of the bears demonstrated a shortening of the QTi as their core temperature reached 21.8°C. After this point, the QTi began to prolong. This perturbation was not seen in human subjects, and was an unexpected finding. Does the hibernating heart attempt to resist hypothermia? Supported by ONR, NSF.
Comparison of properties of intrinsic and extrinsic thumb muscles in humans
Authors: Hermanson John W , Riskin Daniel K , Valero‐Cuevas Fransisco
Published: June 2021

Despite interest in rehabilitation and functional stimulation of impaired hand/forearm muscles there is a gap in knowledge of the underlying muscle function. This study utilized histo‐ and immunocytochemistry and SDS‐PAGE, and estimated fiber lengths of intrinisic and extrinsic thumb muscles. The present study reports data on opponens and adductor pollicis, and flexor pollicis brevis (intrinsic thumb muscles) and flexor pollicis longus (FPL: extrinsic muscle). Whereas opponens fiber lengths were about 22 mm and mean type I composition was 77%, FPL had a mean fiber length of 56 ± 0.3 mm coupled with a mean type I fiber composition of 65%. The adductor (3 regions) had a type I composition of about 67% and fiber lengths of about 15 mm. The extrinsic muscle has longer fibers and a faster profile than the intrinsic muscles, exemplifying a division of labor between muscles that are “packed into” the confines of the hand as compared to longer muscle systems aligned along the forearm. Supported in part by Whitaker Foundation, NSF Grants 0237258, 033366, and IBN9819985 and NIH Grants AR050520 and ARO52345.
Maternal immune stimulation improves gestational outcome of congenital toxoplasmosis
Authors: Hrubec Terry C , Chavan Vrushali , Lindsay David S , Holladay Steven D
Published: June 2021

Toxoplasma gondii, a protozoan parasite annually infecting 1.5 million people in the US, can cause devastating effects if infection occurs during pregnancy. Congenital toxoplasmosis results in stillbirths, hydrocephalus, blindness, mental retardation, and neurological and behavioral disorders. In mice, maternal immune stimulation dramatically reduces teratogen induced birth defects. The protective effects of maternal immune stimulation on infectious causes of birth defects like congenital toxoplasmosis are unknown and were investigated. Mice were immune stimulated with IFNγ prior to breeding and were then infected orally with 30 T. gondii tissue cysts on day 3 of gestation. Fetal malformations and mortality was determined on gestational day 17 from the following treatment groups: Control, T. gondii only, IFNγ only, and IFNγ + T. gondii. Immune stimulation with IFNγ increased fetal survival from 23% to 58% and decreased fetal resorptions from 77% to 29% in T. gondii exposed fetuses. Proportionally more of the resorbed fetuses from IFNγ + T. gondii dams were late gestational indicating improved early embryonic survival. Unexpectedly, dams treated with IFNγ + T. gondii had a 30% mortality rate. Further studies are needed to identify the cause of maternal mortality and determine whether improved gestational outcome translates into improved postnatal function. Supported by USDA AD‐421 137196.