bluuebunny/crossref_metadata_2025 huggingface dataset:
A calcium and vitamin D fortified food product improves bone adaptation during military training (634.3)
Authors: Gaffney‐Stomberg Erin , Lutz Laura , Hughes Julie , Murphy Nancy , Marchitelli Louis , Cable Sonya , Young Andrew , McClung James
Published: June 2021

Stress fracture incidence during military training is high. Prior work suggests calcium (Ca) and vitamin D (vit D) intakes above the RDA may reduce fracture incidence in female trainees. How Ca and vit D affect measures of bone density and strength during initial military training (IMT) is not known. This randomized, double‐blind, placebo‐controlled trial was conducted to determine whether Ca and vit D (2000 mg and 800 IU) delivered as 2 snack bars daily throughout 9 wks of IMT improved trainee bone health. Measures of bone density pre‐ and post‐IMT and strength were assessed using peripheral quantitative computed tomography (n=20 men, n=27 women). Tibia scans were performed on the non‐dominant leg at 4, 14 and 66% of the segment length proximal to the distal end plate. Several parameters increased during training including: trabecular volumetric bone mineral density (vBMD) and bone strength index at the 4% site, cortical vBMD at the 14% and 66% sites, and stress strain index at the 66% site suggesting bone strength improved during IMT (all P<0.05). Those who received Ca and vit D had greater increases in total vBMD at the 4% site (3.0 ± 3.3 vs. 1.2 ± 2.4%; P<0.05) as well as cortical thickness (1.9 ± 2.2 vs. 0.6 ± 1.8%; P<0.05) and bone mineral content (1.6 ± 1.6 vs 0.6 ± 1.8%; P<0.05) at the 14% site. These data indicate that Ca and vit D intakes above the RDA may support bone health during periods of high turnover such as IMT.

Grant Funding Source: Research supported by: ORISE and USAMRMC.
Umbilical cord coiling in adolescent and multiples pregnancies: associations with iron status (636.4)
Authors: Durlacher Jocelyn , Katzman Philip , Lee Sunmin , Guillet Ronnie , Pressman Eva , Cooper Elizabeth , O'Brien Kimberly
Published: June 2021

Abnormal umbilical cord coiling has been associated with adverse neonatal outcomes. The etiology remains controversial. Perturbations in maternal and neonatal iron (Fe) homeostasis have been associated with abnormal cord coiling. This study was undertaken to examine associations between cord coiling and Fe status, in two obstetric groups at risk for iron deficiency (n=166): pregnant adolescents (蠄18 y, n= 95) and adult women carrying twins (n= 43) and triplets (n= 28). Umbilical cords were classified as hypo, normo, or hyper‐coiled using digital photographs to assess gross appearance after training on degree of coiling of actual cords. Hypo‐coiling and hyper‐coiling were observed in 46% (n=77) and 11.5% (n=19) of the study population. Adolescents with hyper‐coiled cords had lower serum ferritin (SF) (p = 0.01, n=11) and higher ratio of serum transferrin receptor (sTfR) to SF (p = 0.04, n=11) at mid‐gestation (27.7 ± 3.4 wks), and lower cord hepcidin (p= 0.02, n= 17) at birth (39.7± 1.5 wks) compared to teens with normo‐coiled cords (n=25 for SF and sTfR, n= 44 for hepcidin). The prevalence of hypo‐coiling observed among women carrying multiples was at least 3‐fold higher than the prevalence expected in singleton pregnancies. Data analyses for Fe status in multiples pregnancies are in progress. Findings to date suggest that decreased Fe status in adolescents is associated with hyper‐coiling of the umbilical cord.

Grant Funding Source: Supported by USDA 2005‐35200; 2008‐01857; the Gerber Foundation
The changing dynamics of maternal nutrition in urban Nepal: findings from a longitudinal study in Bhaktapur (641.17)
Authors: Chandyo Ram , Thorne‐Lyman Andrew , Ulak Manjeswori , Shrestha Prakash , Fawzi Wafaie , Locks Lindsey , Henjum Sigrun , Strand Tor
Published: June 2021

Nepal is undergoing a nutrition transition in which overweight and obesity are becoming issues of increasing public health concern particularly in the urban, and coexist with undernutrition in the rural communities. More evidence is required to understand the evolution of the rise in overweight in different sub‐populations within Nepal. In 2007‐2008, a representative survey was undertaken among 500 healthy lactating women and their infants, randomly selected in Bhaktapur municipality, Nepal. From these mother‐infant pairs, we collected dietary information and blood samples. Five years later, 325 women and their children were followed up and compared with the baseline data. The prevalence of overweight among the women increased markedly_from 17% to 42%. The prevalence of low BMI (<18.5), which affected 4% of women at baseline decreased to 2%. In apparent contrast to the increased maternal overweight, the prevalence of women with anemia increased in this population (17% in baseline compared with 36% in the follow up survey). In this poster/presentation, we will also examine dietary patterns and factors associated with overweight. Data from our cohort suggests that overweight and obesity is rapidly rising among adults in Nepal.

Grant Funding Source: USAID, NUFU and the Research Council of Norway, and the Reiber foundation
Critical role of phosphodiesterase 4 in alcohol induced hepatic steatosis (653.11)
Authors: Avila Diana , Zhang Jingwen , McClain Craig , Barve Shirish , Gobejishvili Leila
Published: June 2021

Alcohol induced hepatic steatosis is a significant risk factor for progressive liver disease. Cyclic adenosine monophosphate (cAMP) has been shown to play a significant role in the regulation of hepatic lipogenesis. Our recent work demonstrated that cAMP degrading PDE4 enzymes are expressed in the liver. The aim of this study was to examine the effect of alcohol on hepatic PDE4 expression and its potential role in the development of alcoholic steatosis. C57Bl/6 and pde4b knockout (pde4b‐/‐) mice were pair‐fed control or ethanol liquid diets for 4 weeks. One group of mice received rolipram, a PDE4 specific inhibitor. We demonstrated that alcohol feeding leads to an early up‐regulation of PDE4B and D accompanied by increased expression of fatty acid synthase and SREBP‐1. Pde4b‐/‐ mice and mice treated with rolipram were significantly protected from alcohol induced hepatic steatosis. An increase in CYP2E1 expression was similar in wild type and pde4b‐/‐ mice, but was decreased by rolipram. These results indicate that hepatic PDE4B plays a significant role in regulating lipogenesis, whereas PDE4D affects CYP2E1 expression and alcohol metabolism. Taken together, these data suggest that hepatic PDE4 expression is a clinically relevant target, and its inhibition can significantly attenuate the development of alcohol induced hepatic steatosis.

Grant Funding Source: Supported by NIH, DOD and Veterans Administration
Attenuation of chronic‐binge alcohol‐induced liver injury by Lactobacillus rhamnosus GG culture supernatant via inhibition of intestinal barrier dysfunction (653.12)
Authors: Zhang Min , Wang Yuhua , Liu Yanlong , Zhao Cuiqing , McClain Craig , Feng Wenke
Published: June 2021

Binge drinking after chronic alcohol consumption is one of the important factors contributing to the progression of hepatic steatosis to steatohepatitis. Our previous study showed that Lactobacillus rhamnosus GG (LGG) culture supernatant (LGGs) ameliorated acute alcohol‐induced liver injury. The present study investigated the effects and potential mechanisms of LGGs on chronic‐binge alcohol‐induced liver injury. Mice were fed Lieber DeCarli diet containing 5% alcohol for 4 weeks, then gavaged single dose of alcohol at 5 g/kg and lasted for 6 hours. Chronic‐binge alcohol exposure induced marked increase in hepatic steatosis and injury, which were attenuated by LGGs supplementation. LGGs application prevented chronic‐binge alcohol‐elevated intestinal permeability and circulating endotoxin level, indicating a beneficial effect of LGGs on intestinal barrier integrity. Further studies demonstrated that the effect of LGGs is through increasing intestinal tight junction proteins and proteins involved in the barrier homeostasis, such as ZO‐1, occludin, p‐glycoprotein, HIF‐2a and intestinal trefoil factor. LGGs also inhibited intestinal microRNA 122a expression, which has been shown to decrease occludin protein translation. In summary, LGGs is effective in preventing chronic‐binge alcohol‐induced liver injury by improving intestinal barrier function.

Grant Funding Source: Supported by NIH, DOD and Veterans Administration
Mechanisms for reactive and sustained pressure dilation (677.4)
Authors: Chin Joseph , Land Douglas , Jasperse Samara , Jasperse Jeffrey
Published: June 2021

We previously found that arteries actively dilate upon return to baseline intraluminal pressure after a brief reduction in pressure (reactive dilation), where the magnitude of dilation is dependent on duration of pressure reduction. We sought to determine the signaling mechanism responsible. Rat soleus feed arteries were isolated and cannulated for in vitro videomicroscopic observation. Pressure was reduced from 115 to 14 cmH2O for 2 min periods followed by a return to 115 cmH2O. Integrin inhibition (0.5 mM RGD peptide) (N=9) reduced reactive dilation (Con: 36.1±3.5%, RGD: 24.2±5.7%). Washing out RGD peptide restored dilation. Specific β3 integrin inhibition (0.5 mM F11 function blocking antibody) (N=7) (blocker) did not reduce reactive dilation. We also examined the initial dilation phase (prior to myogenic constriction) to sustained increases in pressure (80 to 135 cmH2O). Integrin inhibition failed to inhibit dilation, but combined endothelial inhibition (0.3 mM nitroarginine, 0.01 mM indomethacin, and 20 mM K+) reduced dilation (Con: 34.8±8.7%, inhibited: 10.2±3.1%). Combined nitroarginine and 20 mM K+ failed to inhibit dilation. These data suggest that reactive dilation is dependent on non β3 integrins. The data also suggest that initial dilation to sustained pressure increases is partially dependent on prostacyclin and that reactive and sustained pressure dilation utilize different mechanisms.

Grant Funding Source: Supported by NSF #DBI‐1062721 and the Seaver Research Council
Gender differences in muscle sympathetic nerve activity and arterial pressure oscillations during progressive central hypovolemia (680.2)
Authors: Carter Robert , Hinojosa‐Laborde Carmen , Convertino Victor
Published: June 2021

INTRODUCTION: Increased tolerance to central hypovolemia is generally associated with greater oscillatory patterns of mean arterial pressur (MAP) and greater physiological reserve capacity. We tested the hypothesis that women with high tolerance (HT) to hypovolemia would display similar physiological reserve capacity for tachycardia, sympathoexcitation, oscillations in MAP at pre‐syncope compared to men. METHODS: 9 men and 4 women were exposed to progressive lower body negative pressure (LBNP) until presyncope. All subjects were classified as HT because they completed at least ‐60 mmHg level of lower body negative pressure (LBNP). Muscle sympathetic serve activity (MSNA) was measured via microneurography and arterial pressure was measured by photoplethysmography. RESULTS: LBNP time to presyncope was lower (P<0.01) in women (1727±154 sec) than in men (2035±308 sec). At presyncope, MSNA (bursts/min) in men and women was similar (p=0.87). Coincident with smaller stroke volume (SV), women had lower MAP but similar heart rates compared with men. MAP/MSNA coherence was higher (p =0.04) in men (0.77±0.10) than women (0.67±0.04). Women had lower (p =0.06) oscillations in MAP compared to men. CONCLUSIONS: Our data corroborate the hypothesis that lower tolerance in women is not related to differences in sympathoexcitation or tachycardia, but reduced coherence (MSNA/MAP) and lower oscillatory patterns in MAP.

Grant Funding Source: Department of Defense
Greater muscle protein synthesis and mitochondrial biogenesis during sprint interval training in males compared with females (702.2)
Authors: Scalzo Rebecca , Peltonen Garrett , Binns Scott , Giordano Gregory , Hartley Dylan , Klochak Anna , Lonac Marc , Paris Hunter , Szallar Steve , Wood Lacey , Peelor Frederick , Price John , Shankaran Shuba , Hellerstein Marc , Bell Christopher , Hamilton Karyn , Miller Benjamin
Published: June 2021

Improvement in endurance exercise performance in adult humans following sprint interval training (SIT) has been attributed to mitochondrial (mito) biogenesis. However, this conclusion has been inferred from mito biogenic signaling, and not synthesis of new mito protein. Muscle protein synthesis (MPS) and mito biogenic responses to SIT have not been measured, nor have sex‐specific responses. We hypothesized that males and females would have similar rates of MPS, mito biogenesis, and overall individual protein synthetic rates after 9 sessions of SIT. 21 healthy adults (11 male, 10 female, 23±1 years, body mass index: 22.8±0.6 kg/m2; mean±SE) were orally administered deuterium oxide (D2O) for measurements of protein synthetic rates for 4 weeks while completing SIT. Maximal oxygen uptake increased (males from 43.4±2.1 to 44.0±2.3; females from 39.5±0.9 to 42.5±1.3 ml/kg/min; P=0.002) following SIT. MPS was greater in males compared with females in the mixed (150%; P<0.001), cytosolic (135%; P=0.038), and mito (135%; P=0.056) fractions. Kinetic proteomics identified 60 proteins that responded differently to SIT between the sexes (P<0.05); all were greater in males. For the first time, we document greater MPS and mito biogenesis in response to SIT in males compared with females, and present the first data describing the synthetic response of individual proteins in humans during exercise training.

Grant Funding Source: Supported by the Office of Naval Research (N00014‐10‐1‐0247)
Towards a molecular understanding of allostasis in free‐ranging marine mammals (703.6)
Authors: Khudyakov Jane , Champagne Cory , Crocker Daniel
Published: June 2021

Chronic stress negatively affects reproduction and survival of pelagic predators, threatening ecosystem stability. However, our understanding of the stress response in marine mammals is limited and largely based on terrestrial model systems that do not reflect pelagic life history adaptations. We are examining the molecular signature of allostasis in northern elephant seals to develop species‐specific stress diagnostic tools and resolve interactions between the hypothalamic‐pituitary‐adrenal (HPA) axis and other physiological pathways. We conducted stress tests in juvenile elephant seals by intramuscular adrenocorticotropic hormone (ACTH) injection to analyze the magnitude and duration of the HPA axis response. To investigate global gene expression changes in response to a stress challenge, we sequenced RNA isolated from muscle tissue of animals before and after ACTH injection. De novo transcriptome assembly and analysis was performed using the Trinity platform and yielded a reference transcriptome for the northern elephant seal study system. We have identified a number of genes and pathways altered during the stress response in a free‐ranging marine mammal, including several candidate molecular markers of stress. Our data indicate that the magnitude of the stress response to ACTH stimulation provides key information about an animal’s physiological state.

Grant Funding Source: Office of Naval Research
Cerebrovascular compliance is not associated with acute mountain sickness following staged ascent to 4300 m (708.3)
Authors: Guerriere Katelyn , Beidleman Beth , Fulco Charles , Kenefick Robert , Staab Janet , Andrew Sean , Muza Stephen
Published: June 2021

We hypothesized that a reduction in cerebrovascular compliance (∆V), due to cerebral edema, would be associated with acute mountain sickness (AMS) following staged ascent to 4300 m. Forty‐five unacclimatized men and women (mean±SD; 24±5 yr) were exposed to 48 h at a staging altitude at or above 2500 m followed by 24 h at 4300 m. AMS was assessed using the Environmental Symptoms Questionnaire. Near‐infrared spectroscopy was used to assess ∆V within the right frontal lobe via calculation of change in relative total hemoglobin concentration from resting baseline to peak value during a valsalva maneuver to a fixed pressure. Hemoglobin and hematocrit were measured to calculate changes in plasma volume (PV). All assessments were completed at rest in the morning at sea level (SL) and after 24 hours at 4300 m (HA). AMS severity increased (P<0.001) from SL (0.07±0.15) to HA (0.44±0.43). ∆V also increased (P<0.001) from SL (3.08±0.35) to HA (4.60±0.49). PV decreased (P<0.001) from SL to HA (‐17.3±7.1%). No relationship was found between the change in ∆V from SL to HA and the change in AMS severity (r=0.04;p=0.78), but the change in ∆V was significantly associated with the % change in PV (r=0.34;p=0.01). We conclude that ∆V was not related to AMS, potentially caused by cerebral edema, but rather hemoconcentration following staged ascent to 4300 m. Funding: USAMRMC. Authors’ views not official US Army or DOD policy.

Grant Funding Source: Supported by USAMRMC
Ascending projections of the nucleus retroambiguus target key areas of the ponto‐medullary respiratory network (714.1)
Authors: Jones Sarah , Stanic Davor , Dutschmann Mathias
Published: June 2021

Purpose: We aim to elucidate the role and contribution of the nucleus retroambiguus (NRA) in the generation of respiratory rhythm. We previously identified a putative rhythmogenic area 1.5 mm caudal to obex, destruction of which abolished respiratory rhythm in the in‐situ perfused brainstem‐spinal cord preparation of rat. Histological analysis indicated that the putative rhythmogenic cell population resides at the planar level of the pyramidal decussation, therefore likely to overlap with the NRA. We investigated possible involvement of the NRA in rhythm generation by mapping its neuronal connectivity in rat. Methods: Anterograde neuronal tracer, biotinylated dextran amine, was injected into the NRA. Respiratory areas in which labelled terminal fields were seen were injected with retrograde tracer Fast Blue in subsequent experiments. Results: Anterograde tracing from the NRA revealed dense clusters of labelled nerve terminals within important respiratory nuclei including the pre‐Bötzinger complex (PBC), parafacial respiratory group (pFRG) and Kölliker Fuse nucleus (KF). Injection of retrograde tracer into PBC, KF and pFRG show clusters of retrogradely labelled cell bodies in the NRA. Conclusion: Our data provides the anatomical framework for a rhythmogenic role of the NRA within the respiratory network.

Grant Funding Source: ARC
Increased cardiac output, not pulmonary artery systolic pressure, increases blood flow through intrapulmonary arteriovenous anastomoses and impairs pulmonary gas exchange efficiency (717.2)
Authors: Elliott Jonathan , Duke Joseph , Futral Joel , Goodman Randall , Hawn Jerold , Lovering Andrew
Published: June 2021

Sources of venous admixture (QVA/QT) that impair pulmonary gas exchange efficiency, defined by an increased alveolar‐arterial PO2 difference (AaDO2), are ventilation‐perfusion inequality (VA/Q), diffusion limitation, and shunt. Blood flow through intrapulmonary arteriovenous anastomoses (QIPAVA) increases QVA/QT and the AaDO2. However, it is unclear whether increased cardiac output (QT) or pulmonary artery systolic pressure (PASP) cause the increase in QIPAVA. We hypothesized that an increase in QT alone would increase QIPAVA resulting in an increased AaDO2 at rest breathing room air and 40% O2 to prevent contributions from diffusion and VA/Q. Epinephrine, i.v. at 320 ng/kg/min (EPI), and low dose epinephrine (80 ng/kg/min) combined with 2 mg of atropine (EPI+ATR) were used in healthy human subjects (n=5) to increase QT. When breathing either room air or 40% O2, EPI and EPI+ATR increased QT, (measured by acetylene uptake) from 7.8±1.0 to 13.3±3.4 L/min. Only EPI significantly increased PASP (to 54±14 mmHg), measured with ultrasound, but not with EPI+ATR (to 39±5 mmHg). However, EPI and EPI+ATR, breathing either room air or 40% O2 resulted in equal QIPAVA detected with saline contrast echocardiography. Furthermore, with EPI and EPI+ATR, the AaDO2 increased significantly when breathing either room air or 40% O2. Consistent with our data above, the calculated QVA/QT required to account for the entire AaDO2 was 2.4±0.4% with EPI and EPI+ATR, breathing either room air or 40% O2. We conclude that increased QT alone significantly increases QIPAVA and AaDO2 in healthy humans.

Grant Funding Source: Supported by: Department of Defense #W81XWH‐10‐2‐0114, AHA Predoctoral Fellowship
Examining causes and contributors to falls in Parkinson disease (728.9)
Authors: Smith Lorinda , Hunt MaryEllen , Dibble Lee , Merryweather Andrew , Foreman K
Published: June 2021

The high incidence of falls in people with Parkinson disease (PPD) (>70% fall each year, 13% fall > once/week) is attributed to central nervous system damage that disturbs movement amplitude regulation and sensory processing. Despite this, PPD are capable of learning motor tasks with practice. Virtual environments are being developed to provide safe repetitive practice in an effort to decrease falls. To inform the development of these environments, we examined causes and contributors to falls from the perspective of PPD. Eleven men with mild to moderate PD completed a semi‐structured, mixed methods interview. Subjects rated environments on a scale from 1 (never difficult to walk or maintain balance) to 5 (always difficult), and descriptive statistics were calculated. They answered open‐ended questions about mobility and falls, and coding was used to categorize this data. The most difficult surface type was “Unreliable/Unstable” (e.g. loose gravel, mean=3.64), followed by “Irregular/Inconsistent” (e.g. cobblestones, mean=3.09) and “Angled” (mean=3.09). “Visual Factors” (e.g. glare, mean=3.09) were rated similarly. Multitasking and feeling rushed or worried were identified in open‐ended responses as common contributors to falls in the “Distracting” category (mean=2.91). “Obstacles” were rated as moderately difficult (mean =2.22), but were identified as a frequent concern and contributor to falls when fall history was examined. The most challenging scenarios combined several of these factors. With this knowledge, virtual environments that allow for motor learning through safe practice of challenging scenarios are being created. Future research is necessary to determine to what extent this virtual‐based learning will transfer to real‐world scenarios, and the dosage of practice necessary to achieve a functional decrease in falls in PPD.

Grant Funding Source: Supported by NSF 1162131
Gene control using tRNA‐shRNA chimeras: knockdown by shRNA and degradation of tRNA (749.3)
Authors: Zazueta Christopher , Stork Devon , Haushalter Karl
Published: June 2021

Gene therapy using RNA interference (RNAi) mediated by short hairpin RNAs (shRNAs) targeted against HIV‐1 is a promising alternative to antiretroviral therapy. Fusing shRNA to carrier tRNA to produce a tRNA‐shRNA chimera can provide a tunable level of shRNA delivery that is dependent on the action of the enzyme tRNaseZ to separate the shRNA and tRNA components of the chimera. We have introduced changes in the sequence of the acceptor stem of the tRNA portion of the tRNA‐shRNA chimera to produce the next‐generation of tRNA‐shRNA chimeras. Our targeted mutations are designed to result in an isomerization that triggers rapid tRNA decay after release of the shRNA by tRNaseZ. The knockdown efficiency of the resulting constructs can be assayed by a dual luciferase assay.

Grant Funding Source: Supported by NSF CHE‐1005253
Aminotransferase activity of a novel aminoacyl‐tRNA synthetase appended domain (751.3)
Authors: Sharma Sandhya , Alexander Rebecca
Published: June 2021

Aminoacyl‐tRNA synthetases (AARSs) are key enzymes in protein biosynthesis, responsible for attaching amino acids to the 3ʹ‐end of cognate tRNAs. The AARSs are modular proteins, with separate polypeptide domains responsible for tRNA binding and catalysis; additional domains on some AARSs contribute oligomerization, localization, and editing functions. The opportunistic pathogen Mycoplasms penetrans expresses an unusually long version of methionyl‐tRNA synthetase (MetRS) that contains an extra N‐terminal domain with sequence homology to class V aminotransferases. We anticipated that this domain carries out pyridoxal phosphate (PLP)‐dependent aminotransferase activity, possibly to modify Met‐tRNA(Met) for enhanced pathogenicity.

We overexpressed and purified M. penetrans MetRS (MpMetRS) and used the amino‐reactive aromatic dialdehyde naphthalene‐2,3‐dicarboxaldehyde followed by HPLC to analyze enzyme activity in vitro. Initial characterization confirms the proposed aminotransferase activity, with several amino acids and α‐keto acids serving as amino group donors and acceptors, respectively. Substitution of amino acids in the transferase and synthetase catalytic sites indicate that these activities are independent. Ultimately we seek to identify the cellular substrates and implications of the MpMetRS aminotransferase activity.

Grant Funding Source: Supported by the National Science Foundation
The role of oxyanion holes in the structure and function of type III polyketide synthases (768.18)
Authors: Stewart Charles , Noel Joseph
Published: June 2021

The objective of this study was to combine the tools of protein crystallography and enzyme kinetics to explore the structural mechanisms of type III polyketide synthases (PKSs). Type III PKSs are proteins involved in diverse metabolic processes including cell signaling, pathogen defense and the development of reproductive cells. Mechanistically, these enzymes generate metabolites through the repetitive addition of acetate units onto a starter molecule; a process that produces reactive intermediates that are ultimately cyclized into the final product. How these enzymes control their reactive intermediates and terminal cyclizations is not fully understood and is a major hindrance to protein engineering efforts. We present here our results describing the role of oxyanion holes in the mechanism of type III PKSs. Crystallographic studies of reaction analogs trapped in the active site revealed that remnants of an ancient oxyanion hole are involved in stabilizing reactive intermediates. Unexpectedly, we observed that a small molecule, metazachlor, has different conformations in the active site of functionally distinct PKSs. Enzyme kinetic studies supported our structural findings by establishing that metazachlor differentially inhibits type III PKSs based on their terminal cyclization steps. These structure‐function studies are being used as a guide for altering the terminal cyclization preferences of type III PKSs to build novel compounds.

Grant Funding Source: Supported by Howard Hughes Medical Institute and National Science Foundation
Probing the role of S28 in Thermodesulfovibrio yellowstonii adenonsine diphosphate glucose pyrophosphorylase: insight in to allosteric regulation and sensitivity (769.14)
Authors: Susoeff Michael , Yik Eric , Badal Matthew , Kaur Sandeep , Almendarez Jessica , Almendarez Jessica , Meyer Christopher
Published: June 2021

Renewable and biodegradable glucans are in demand for use in a variety of industries. Adenosine Diphosphate Glucose Pyrophosphorylase (ADPG PPase), an allosterically regulated enzyme, serves as the rate limiting step in glucan biosynthesis and is an attractive target for protein engineering to increase yield. The enzyme from Thermodesulfovibrio yellowstonii (Td.y) has been successfully expressed in E. coli and a purification scheme that includes hydroxyapatite and anion exchange chromatography optimized. The inclusion of 250 mM NaCl in the running and storage buffers increased the yield and solubility (over 20 mg/mL) of the enzyme. The Td.y ADPG PPase contains a primary sequence that deviates from consensus in the conserved KRAKPAV region (amino acids 23‐29), shown to be important for activity and regulation. To explore its role, the S28A enzyme was generated and characterized with respect to temperature, pH, and kinetic parameters for substrates and effectors. The S28A altered enzyme was found to have the same optimal temperature (70°C) and pH (8.5) as the wild type (WT) enzyme. While the specific activity in the absence of activators was found to be 2‐fold lower than WT, the fold activation response to the allosteric activators, phosphoenolpyruvate, fructose‐1,6‐bisphosphate, glucose‐6‐phosphate, and 3‐phosphoglycerate, was 2‐3 fold higher than WT. Thus position 28 plays a role in sensitivity to allosteric activation. Complete kinetic analyses of the S28A enzyme and other altered proteins are underway, as well as crystallization trials as a first step in solving the three‐dimensional structure.

Grant Funding Source: NSF Grant 0448676
Structure‐function studies of the ADPglucose pyrophosphorylase from Thermotoga maritima: probing the role of a conserved aspartate residue in the glgD and glgC subunits (769.20)
Authors: Vu Crystal , Arteaga Adrianna , Jacobs‐Edmonson Raymond , Meyer Christopher
Published: June 2021

ADPGlucose pyrophosphorylase (ADPG PPase, glgC gene) catalyzes the rate‐limiting step of glucan biosynthesis in plants and bacteria. Structure‐function studies of the diverse forms of the enzyme will allow for the engineering of a more active enzyme to produce more renewable carbon. In Thermotoga maritima (T.ma) there are two genes, glgC and glgD, which code for two subunits of this ADPG PPase. The recombinant His‐tagged subunits were successfully purified using a heat step and nickel chromatography; the wild type (WT) glgD alone had little to no activity, while the glgC protein displayed a specific activity of ~3 Units/mg with S0.5 values for ATP and magnesium (Mg) of 5.4 mM and 18.7 mM, respectively. However, the WT glgC/D complex was stimulated ~5‐fold compared to glgC alone and also activated ~2‐fold by FBP. Previous alignment studies and molecular modeling indicated that glgC D126 plays a role in catalysis so the D126A enzyme was generated to test this hypothesis. The glgC D126A protein displayed a modest increase in apparent affinity for substrates compared to WT but a 25‐fold decrease in Vmax indicating a role in optimal catalysis. Interestingly, the inactive glgD protein also harbors an aspartate (D125) at this position and the D125A glgD enzyme was generated for characterization. Surprisingly, the altered protein was found to have activity with S0.5 values for ATP, Mg, and G1P of 4.90 mM, 14.8 mM, and 39.2 µM, respectively, with a Vmax of 0.26 U/mg. In preliminary assays, we found that the glgD D125A/glgC complex displayed only a small stimulation compared to glgC alone while the glgD/glgC D126A complex displayed stimulation comparable to WT; a very large stimulation of activity was found when the glgD D125A/glgC D126A was combined, rising to the level of the glgD D125A/glgC2 complex. These aspartate residues may affect activity and stimulation of the subunits in a complex in a synergistic manner. Complete kinetic and physical characterization of the altered enzyme complexes is underway.

Grant Funding Source: Supported by NSF award 0448676.
Maternal anemia, iron deficiency, and pregnancy outcomes in India (804.10)
Authors: Finkelstein Julia , Duggan Christopher , Thomas Tinku , Bose Beena , Samuel Tinu , Srinivasan Krishnamachari , Kurpad Anura
Published: June 2021

Objective: To examine the burden of anemia and iron deficiency and its association with pregnancy outcomes in women in India.

Methods: A total of 366 pregnant women who were participating in a vitamin B12 supplementation trial in India were monitored to assess the associations of maternal hematological status during pregnancy (hemoglobin, ferritin, CRP, AGP) and birth outcomes. Binomial and linear regression models were used to evaluate the associations between maternal iron status and pregnancy outcomes.

Results: Anemia and iron deficiency were common in pregnancy: 30% of women were anemic (Hb<11.0 g/dL), 40% were iron deficient (ferritin<12 µg/L), and 22% had iron deficiency anemia. Maternal anemia predicted 2.4 times greater risk of preterm delivery (p<0.01) and increased risk of low birth weight (p=0.05). Maternal iron deficiency predicted a 2.5‐fold higher risk of preterm delivery (p<0.01), and iron deficiency anemia predicted a three‐fold greater risk of preterm delivery (p<0.001).

Conclusions: Anemia, iron deficiency, and iron deficiency anemia are common in pregnant Indian women and are associated with increased risk of adverse pregnancy outcomes.

Grant Funding Source: Supported by: NICHD, ICMR, NIHK24; HIGH, SAI, Rose, SJRI, and DNS.
The effect of prenatal multiple micronutrient supplementation on biomarkers of placental angiogenesis in rural Bangladesh (804.2)
Authors: Gernand Alison , Schulze Kerry , Shaikh Saijuddin , Shamim Abu , Ali Hasmot , Wu Lee , West Keith , Christian Parul
Published: June 2021

Prenatal multiple micronutrient (MM) supplementation improves birth weight through increased gestational age, yet it is unknown if improved placental function contributes to this effect. We assessed the effects of prenatal MM vs. iron and folic acid (IFA) on placental angiogenesis (the formation of blood vessels from existing ones) in a subset of women (n=395) participating in a double blinded, cluster‐randomized trial in rural Bangladesh. Angiogenic factors assessed in maternal plasma at 10 and 32 weeks gestation were placental growth factor (PlGF), angiopoietin 2 (Ang‐2), vascular endothelial growth factor (VEGF), and VEGF receptor 1 (VEGFR‐1). Concentrations were similar at baseline (10 weeks); PlGF, VEGF and VEGFR‐1 increased from the first to third trimester, whereas Ang‐2 decreased in both groups (p<0.01). At 32 weeks, PlGF and Ang‐2 were positively associated with gestational age and placental weight at birth and VEGFR‐1 was positively associated with placental weight (all p<0.05). Ang‐2 was 3.1 (95% CI: 0.20, 6.0) ng/mL higher at 32 weeks in mothers taking MM vs. IFA. There was no difference between MM and IFA groups in other angiogenic factors at 32 weeks, or their change from 10 to 32 weeks. MM supplementation improved angiogenic Ang‐2, reflective of enhanced placental vascular remodeling that may explain part of the MM impact on birth size through increased gestational age.

Grant Funding Source: Supported by The Thrasher Research Fund, NIH (T32HD046405), The Gates Foundation, and USAID
National WIC infants and toddlers feeding study (805.15)
Authors: Harrison Gail , McNutt Suzanne , Weinfield Nancy , MacAllum Crystal , Owens Tameka
Published: June 2021

This is a nationally representative longitudinal study of contemporary feeding practices for the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) (infants and toddlers in low‐income households and deemed at nutritional risk) population. The study is currently in the field (80 sites, 26 states and one territory); all local and state IRB requirements have been met. Over 4000 women and infants are expected to participate fully; recruitment has been very successful (97% of those invited). Eligible women (English‐ and Spanish‐speaking) are invited/ consented at a WIC enrollment visit. Interviews are conducted prenatally (or at enrollment for those enrolling postnatally within three months of delivery), and up to 10 times during the infant’s first two years of postnatal life. The USDA‐developed Automated Multiple Pass Method 24‐hr recall is utilized to collect 24‐hr dietary data for the child at every interview, and the six‐item USDA food security questionnaire is asked at five interviews. The projected database will be the only current large‐sample longitudinal feeding data representative of children of this age living in low‐income households available for informing the 2020 Dietary Guidelines for Americans.

Grant Funding Source: USDA #AG‐3198‐B‐1‐0020
Baseline characteristics of a pregnant, primarily African American cohort residing in the Mississippi Delta: Delta Healthy Sprouts (806.7)
Authors: Goodman Melissa , Thomson Jessica , Tussing‐Humphreys Lisa
Published: June 2021

Inappropriate gestational weight gain (GWG) is associated with adverse maternal and infant outcomes and increased risk for childhood obesity. Interventions designed to optimize maternal GWG may be effective at improving the health of women and their infants. Delta Healthy Sprouts (DHS) is a randomized, controlled, comparative trial testing the efficacy of two Maternal, Infant, and Early Childhood Home Visiting programs on weight status and health behaviors of mothers and their infants residing in the rural Mississippi Delta. We describe baseline demographic, psychosocial, diet, and physical activity (PA) characteristics of this cohort of women early in their 2nd trimester of pregnancy. The majority of participants are single (88%), African American (94%), and obese (56%), with no more than a high school education (53%), and a mean age of 23 (SD=5.3) years. Over one third (38%) screened for mild to major depression and 91% reported low PA. Mean baseline diet and PA related expectations, social support, and self‐efficacy scores were moderately high, while attitude was low. Half (50%) of the participants were primarily responsible for the household food shopping, 35% for meal preparation; although 31% prepared meals at home less than 4 days/week. Results from DHS will determine if a novel, scalable lifestyle intervention can improve the health of women and their infants in this health disparate region.

Grant Funding Source: Supported by the USDA Agricultural Research Service.
Effects of KidQuest on body mass index, lean body mass and body fat percentage among children ages 11 to 14 years in Nebraska (808.14)
Authors: Chai Weiwen , Fischer Jean Ann , Takahashi Shinya , Wallinga Melissa , Anderson‐Knott Mindy , Wolf Tovah , Koszewski Wanda
Published: June 2021

Objective: Promoting healthy eating and physical activity are key to the prevention of childhood obesity which continues to increase in the U.S. Our study examined the changes in body mass index (BMI), total lean body mass (LBM) and total body fat mass (FM)) in children ages 11 to 14 years after receiving a 6‐week nutrition and physical activity curriculum (KidQuest).

Methods: KidQuest was implemented in after school programs in Nebraska. BMI, LBM, and FM were measured before and after the program in 42 children who had both parental and youth consents. Paired t‐test was used to assess the baseline and post intervention differences in the above measurements.

Results: No significant differences in BMI were observed before and after the intervention. Based on BMI for age percentile, 10% of the children were overweight and 20% were obese at baseline. There were significant increases in LBM after the intervention (pre, 33.1kg, post, 42.0kg, P<0.0001). Decreases in FM were also observed after the program (pre, 15.1kg, post, 13.8kg, P=0.13).

Conclusions: Our observations for changes in LBM and possible FM need to be confirmed with a larger sample size.

Grant Funding Source: USDA (AFRI) Grant No. 2011‐67002‐30202
Accuracy of food guide and nutrition label use by caretakers in the STRONG Kids cohort (808.17)
Authors: Paige Katie , Wallace Victoria , Teran‐Garcia Margarita , Donovan Sharon
Published: June 2021

Childhood obesity rates have risen dramatically in recent decades, compelling researchers to analyze the changing environment surrounding this weight gain. Our goal was to assess parent’s knowledge of food guides and nutrition labels. Parents (n=407) of preschoolers (age 3‐5) reported that moms and grandparents were primarily responsible for selecting meals. Overweight parents had 1.86‐times higher odds of having overweight children (95% CI 1.15‐2.99, p=0.01). Parents of children who were overweight (>85th BMI percentile) had a higher average BMI than parents of children who were normal weight (29.6 vs. 26.6 kg/m2; p=0.0001). Parents’ ability to choose healthy foods may be limited by the way nutrition information is presented. On a nutrition fact label, 35% of parents were unable to correctly complete calculations necessary to interpret nutrition facts. Although 56% of parents attained a Bachelor’s degree or higher, only 32.2% could identify the current USDA food guide. Older and less‐educated parents were more likely to choose an incorrect or outdated food guide (p蠄0.05). The release of multiple food guides in recent decades may have led to consumer confusion. Parent inability to identify current guidelines and interpret nutrition labels suggests poor dissemination of these tools. Clinical settings and grocery stores may serve as opportunities for continued education.

Grant Funding Source: Funded by the USDA (Hatch 793‐328), I‐CAR, and NIFA (2011‐67001‐30101)
The unseen power of parents: the influence of parent physical activity behaviors and values on preschool children’s PA, sleep, and screentime (808.2)
Authors: Martin‐Biggers Jennifer , Cheng Carolyn , Byrd‐Bredbenner Carol
Published: June 2021

This study examined parents’ (n=47) role modeling of PA, importance placed on PA, encouragement of child PA, screentime and sleep hours/day, and PA level and their preschool children’s screentime and sleep hours/day and PA level. Parents were 70% white and 66% had college degrees. Parents had neutral role modeling and positive PA importance and encouragement scores (i.e., 2.99+0.73SD, 3.94+0.65SD, 4.25+0.56SD, respectively, on a 5‐point scale). They had 2.86+2.36SD and 6.98+0.89SD screentime and sleep hours/day, and low to moderate PA level. Children got 3.08+2.92SD and 9.67+1.33SD screentime and sleep hours/day, and had moderate to high PA levels. Child PA level was significantly (p<.05) positively correlated with child sleep hours but was not correlated with any parental measure. Parent sleep was inversely correlated with child screentime hours, suggesting that parents who get less sleep permit screentime more. Child screentime hours and parent BMI were positively correlated with parent screentime. Parent encouragement of and importance placed on PA was associated with their own PA level. Parent sleep, screentime, and PA importance/encouragement are related to child obesity risk factors.

Grant Funding Source: Supported by USDA, National Institute of Food and Agriculture, Grant Number 2011‐68001‐30170
Major American dietary patterns are related to risk of age‐related macular degeneration (810.2)
Authors: Chiu Chung‐Jung , Chang Min‐Lee , Zhang Fang Fang , Li Tricia , Gensler Gary , Schleicher Molly , Taylor Allen
Published: June 2021

Objective: We hypothesized that major American dietary patterns and differences in specific nutrient intakes within the context of the patterns are associated with age‐related macular degeneration (AMD) risk.

Methods: 8,103 eyes from 4,088 eligible participants were classified into control, early AMD, and advanced AMD. Using 37 food group data collected by a 90‐item food frequency questionnaire, two major dietary patterns, prudent and Western patterns, were identified by factor analysis.

Results: For early AMD, the multivariate‐adjusted odds ratio (OR) comparing the highest to lowest quintile of the prudent pattern score was ORE5P=0.74 (95% confidence interval (CI): 0.59‐0.91; Ptrend=0.01), and the OR comparing the highest to lowest quintile of the Western pattern score was ORE5W=1.56 (1.18‐2.06; Ptrend=0.01). For advanced AMD, the ORA5P was 0.38 (0.27‐0.54; Ptrend<0.0001), and the ORA5W was 3.70 (2.31‐5.92; Ptrend<0.0001). Our data also suggested benefit from higher dietary intakes of vitamin C, lutein/zeaxanthin, and beta‐carotene, especially in the context of the Western pattern. In the context of the two major patterns, we did not observe a relationship between intake of vitamin E, zinc, DHA or EPA and AMD risk.

Conclusions: This cross‐sectional study indicates that diet plays an important role in the development of AMD and that the risk for AMD can be diminished by eating a prudent diet.

Grant Funding Source: Supported by the NIH and the USDA
Data‐driven prediction of therapeutic efficacy and optimization of de novo drug combinations on the human protein‐protein interaction network (842.11)
Authors: Wang Hann
Published: June 2021

Combination therapy is a promising direction for cancer research as it is shown to eradicate drug‐resistant cancer more effectively than monotherapy. The challenge, however, in creating a successful combinatorial treatment lies in the inability to screen through a huge number of possible combinations. We introduce PROPHECY (Predictive Optimization of Pharmaceutical Efficacy), a data‐driven search engine for the selection of drugs in combination therapy. The user provides a genetic profile, e.g. mutations in cancer cell lines or primary cells, and PROPHECY will select optimal drug combinations from a comprehensive library of existing drugs to meet clinical objectives. The decision is made by comparing the efficacy of drug combinations with in silico screening, in which a predictive machine is trained with a large‐scale database of drug screening experiments to recognize high‐order target‐gene interactions in the human protein‐protein interaction network (PPI). The predictive module in the machine incorporates knowledge of information propagation in the network, so can accurately elucidate interactions of a group of drug targets and disease genes in a de novo drug combination. Unlike other approaches of reductionistic drug development, PROPHECY can fully acknowledge the synergy between multiple drugs and predict the most effective multi‐target treatment against drug resistant cancer.

Grant Funding Source: Supported by NSF
Ontogeny, ryanodine receptor‐mediated calcium sparks, and BK channel clustering in basilar arterial myocytes from long‐term hypoxic sheep (853.9)
Authors: Glasgow Shane , Tao Xiaoxiao , Romero Monica , Osman Noah , Puglisi Jose , Bers Donald , Izu Leighton , Longo Lawrence , Hessinger David , Wilson Sean
Published: June 2021

Ryanodine receptor (RyR) activity causes Ca2+ sparks in cerebral arterial myocytes by activating adjacent Ca2+‐activated K+ (BK) channels, which can dilate arteries. Previous studies show ontogeny increases Ca2+ sparks and long‐term hypoxia (LTH) increases BK channel activity. We hypothesized that BK channel activity is greater in arterial myocytes of the LTH fetus than adult due to greater spark activity, and because BK channel clustering is greater in regions where sparks occur. To address this hypothesis we examined spark activity and BK channel clustering to sites of potential spark activity. This was accomplished using line‐scan and immunofluorescence techniques, respectively, in basilar arteries from LTH fetal (FH) and adult sheep (AH) kept at 3,801 m for > 100 days. The percentage of myocytes with sparks was ~ 2‐fold greater in FH versus AH and unaffected by 30 mM K (30K). Spark amplitude was 7% greater in FH 30K versus AH 30K, while no spatial or temporal changes to sparks were observed. BK channels were 2‐3 times more clustered and ~1.5 times more co‐localized with cholera toxin B‐labeled clusters in FH. These data suggest greater BK targeting to potential sites of spark activity in FH myocytes. Elevated RyR‐dependent Ca2+ spark activity in FH and altered patterns of BK distribution shed new light on the therapeutic potential of RyRs and BKs for treatment of cerebral vascular disease in newborns and adults.

Grant Funding Source: Supported by NSF MRI 0923559, NIH HD‐069746, P01HD031226, R01HD003807, LLUSOM