bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural implications for ribosomal binding of a 2‐thiocytidine modified nucleotide at position 32 of tRNAArg
Authors: Cantara William A , Kim Jia , Agris Paul F
Published: June 2021

Four of the five arginine tRNAs in E. coli contain a conserved 2‐thiocytidine (s2C) at position 32. The structural implications of this modification and how it impacts ribosomal binding are key to understanding its role in translation. The hypothesis that s2C modification creates specific structural changes in the anticodon stem and loop (ASL) of tRNAArg that result in functional binding differences is tested herein. Using electophoretic mobility, UV melt, circular dichroism, NMR and filter binding assays, we are able to develop structural and functional profiles of an array of unmodified and s2C‐containing arginine ASLs. It is shown that by combining the structural results with binding data creates a comprehensive view of how the complex dynamics of the translational machinery is influenced by the presence of s2C at position 32 of ASLArg. This study is funded by the National Science Foundation.
Thermodynamic Contributions of Divalent Ion Interactions with a Symmetric Internal Loop in RNA
Authors: Furniss Stephanie K , Grover Neena
Published: June 2021

Folding of single stranded RNA upon itself generates complex structures containing many bulges and loops along with A‐form helical regions. These structures contain many structural motifs that are expected to be sites for inter‐ and intra‐molecular interactions. Motifs in which phosphate bonds are in close proximity are expected to require interactions with metal ions to stabilize the RNA structure Thermodynamic studies on an asymmetrical trinucleotide bulge RNA in our laboratory have shown that the divalent ions stabilize the RNA by 3‐5 kcal/mol ( ? ?G° relative to zero). In this study we are examining the thermodynamic properties of symmetrical internal loops and their interactions with divalent ion. We are examining a 2x2 symmetric bulge derived from magnesium binding region of the thiamine pyrophosphate. Initial thermodynamic analysis shows that the symmetrical loop interacts with magnesium ions and is stabilized approximately 1.5 kcal/mol relative to the 0mM buffer. The helix without the bulge was stabilized approximately 2 kcal/mol relative to the 0mM buffer. The competition between monovalent and divalent ions in RNA interactions is also being examined. This work was funded by NSF MCB‐0621509 to NG.
Thermodynamics Examination of Divalent Ion Interactions with Trinucleotide Bulged RNA
Authors: Benson Chloe Merrick , Booth David , Eason Bryan , Grover Neena
Published: June 2021

TAR RNA of HIV‐1 has a trinucleotide bulge region that interacts with the Tat protein of HIV‐1 to increase the rate of transcription. Two base pairs in upper and lower helices surrounding the bulge are conserved. Bulge nucleotides in a helix distort the RNA and hence create recognition sites for target molecules. Previous work in our laboratory has shown that divalent ions such as calcium and magnesium stabilize the RNA with calcium interactions being preferred for the wild type construct (UCU‐TAR). Here we examine the affect of altering the neighboring base pairs on RNA stability and ion preference of a trinuleotide bulge containing RNA. Thermal denaturation experiments were performed on an RNA construct in which the neighboring helix sequences above and below the bulge were altered. This altered RNA containing a UCU bulge was stabilized by ~1.43 kcal/mol in the presence of 9.5 mM magnesium as compared to 1 M KCl, and ~1.04 kcal/mol in the same concentration of calcium. Hence, a change in neighboring base pairs altered the preference and extent of stabilization by divalent ions. In this construct, the putative base triple between bulged U23 and the A27‐U38 is disrupted. Further examination of the role of base triple in RNA interactions with divalent ions is being examined. This work was funded by NSF MCB‐0621509 awarded to NG.
Correlating Divalent Ion Interactions with RNA Structure Changes in TAR RNA
Authors: Hellyer Jessica , Grover Neena
Published: June 2021

The HIV‐1 trans‐acting responsive (TAR) element plays an essential role in transcriptional activation through its interactions with the Tat protein. TAR RNA contains a trinucleotide bulge region that interacts with an arginine rich‐domain of the Tat protein. The presence of an asymmetric bulge in RNA distorts the helix and generates recognition sites for target molecules. Studies in our lab have shown that divalent ions bind to TAR RNA to stabilize the RNA and have demonstrated that calcium ions stabilize the TAR RNA more than magnesium ions. It was also determined that disruption of the bulge sequence (CCC‐TAR) significantly alters interactions with divalent ions. Several biochemical and biophysical studies of TAR RNA indicate that the observed thermodynamic stabilization could be a result of changes in RNA structure. In this study, we sought to determine if TAR RNA interactions with calcium and magnesium ions result in structural changes and if these changes were similar to those caused by interactions with arginine. Circular dichroism experiments were performed on wild TAR RNA containing the UCU bulge and repeated with a modified TAR RNA, which is not expected to bind to arginine. A comparison of structural studies with thermodynamic data will be presented. This work was funded by NSF MCB‐0621509 awarded to Neena Grover.
Thermodynamic Consequences of RNA Editing
Authors: Oliver‐Allen Hunter Scott , Grover Neena
Published: June 2021

RNA editing involves the deletion or insertion of nucleotides. In double stranded RNA, enzymes known as adenosine deaminases that act on RNA (ADARs) catalyze adenosine deamination, the conversion of adenine (A) to inosine (I). RNA editing enhances the complexity offered by the genome. ADAR concentrations are high in the nervous system and defects in editing can cause severe neurological disorders by targeting receptors such as those for serotonin and glutamate. Editing is expected to destabilize the double stranded RNA by creating regions of unpaired bases in the helices. Preference and selectivity of editing sites by ADARs is not fully understood but is attributed to the associated changes in thermodynamic stability of the RNA. In this study, we are measuring changes in RNA stability for edited and unedited RNA constructs based on the serotonin and glutamate receptor sites. The neighboring base pairs of adenine that is being edited influence the RNA stability, as expected based on the nearest neighbor models. Optical melting studies were performed on several different oligoribonucleotides constructs containing adenine or inosine to calculate the thermodynamic changes in RNA under different conditions. The nearest neighbor parameters are calculated using multiple linear regression models. This work is funded by NSF grant MCB‐0621509 (NG).
Insulin oligomers: what and where are they?
Authors: Belfort Georges , Sorci Mirco , Heldt Caryn
Published: June 2021

Recent reports have suggested that (i) oligomers, rather than amyloid fibrils, are toxic and possibly cause disease, and (ii) disease progression occurs in the absence of amyloid fibrils. Using a model amyloid protein, the hormone insulin, we have studied the reaction kinetics pathway from folded native hexamers through oligomers to fibrils. Here we report on several experimental methods to detect and follow oligomers during the prefibrillation stage. Small angle x‐ray and neutron scattering, electrospray differential mobility analysis, ultracentrifugation, circular dichroism and size exclusion chromatography were used. Surprisingly, none of these methods detected measurable concentrations of oligomers. This finding suggests that fibrillogenesis may occur without successive transitions through protofibril nuclei or, more probably, with a nuclei‐induced reaction at very low nuclei concentrations. Other experiments have directly (cryo‐electron microscopy) and indirectly (seeding experiment) detected the presence of aggregated structures. The challenge now is to find a separation technique that will selectively isolate the different oligomers and aggregated structures, critical for determining the molecular basis of amyloid‐related diseases. This work was funded by the U.S. Department of Energy, DOE (DE‐FG02‐07ER46429).
The Effect of Glutamine Insertions on the Structure and Function of gMDH
Authors: Chikowski Rachel , Bell Ellis , Bell Jessica
Published: June 2021

Extended polyglutamine (polyQ) stretches in proteins are known to cause neurodegenerative disease such as Huntington's disease and spinocerebellar ataxia type 3, which are extremely pathogenic and often fatal. Protein misfolding and aggregation are characteristic of polyQ expansion diseases. This study explores the effect of glutamine insertions on glyoxysomal malate dehydrogenase (gMDH) structure and function. Two mutants, 240Q10 and 301Q10, each containing a ten glutamine insert were constructed. Insertion of glutamines and purity were assessed using MALDI‐TOF mass spectrometry. Enzymatic activity of each mutant was compared to native gMDH. Results show decreases in Vmax for both mutants as compared to native, but more drastic decreases for mutant 240Q10. Km values for substrates showed minimal changes. Crystals of 301Q10 were grown under conditions similar to native gMDH. A 2.5 angstrom dataset was collected with a final Rmerge of 0.118, space group P21 (a=90.57, b,c=95.68 angstrom and ?уz ?~z ? ?=90 ?X). The structure was solved by molecular replacement using native gMDH as the probe. Model building and refinement are in progress. Although at this stage in the structural refinement the 10 glutamine insert is not resolved, this mutant¡¦ s crystal lattice packing differs from native gMDH. This research is supported by a grant from the National Science Foundation: MCB 0448905 to EB.
SUMO (small‐ubiquitin‐like modifier) in subcellular fractions of Chlamydomonas reinhardtii reveal potential function
Authors: Miller Amy , Horken Kempton , Matejka Stephanie , Weeks Donald , Bailey Cheryl
Published: June 2021

SUMO (Small ubiquitin‐like modifier), is a member of the family of ubiquitin‐like polypeptides that become covalently attached to intracellular target proteins. SUMOylation can alter the function, location, and/or half‐life of target proteins. Here we describe three SUMO proteins and three SUMO‐like proteins in Chlamydomonas reinhardtii. The three SUMO genes show differential RNA expression depending on environmental conditions. Western analysis also shows a shift in proteins recognized by the Chlamydomonas reinhardtii SUMO antibodies in response to changes in environmental conditions. The three SUMO‐like proteins are novel fusion proteins with C‐terminal SUMO. Chlamydomonas reinhardtii subcellular fractionation reveals SUMO proteins are conjugated to proteins involved in various cellular processes. Proposed SUMOylated target proteins can be resolved by one‐dimensional and two‐dimensional western analysis.

Supported by NSF and the Nebraska Research Council.
Mechanistic steps of metal uploading into Cu+‐transporting ATPases
Authors: González‐Guerrero Manuel , Hong Deli , Argüello José M.
Published: June 2021

Mutations in the two human Cu+‐ATPases lead to either Wilson's or Menkes' diseases. Cu+‐ATPases accept cytoplasmic Cu+ from Cu+‐chaperones and subsequently drive this metal transmembrane transport. It has been postulated that cytosolic metal binding domains (MBDs) have the regulatory role based on their Cu+‐dependent interaction with the ATP‐binding domain. Alternatively, they might affect chaperone‐ATPase interaction. Here, we show that MBDs do not play a role in Cu+ delivery nor affect the interaction of the chaperone with the ATPase. Moreover, nucleotides, as Cu+, prevent the MBDs interaction with the ATP‐binding domain. Interestingly, we also observed that for the chaperone to upload Cu+ to the two transmembrane metal binding sites (TM‐MBSs) present in Cu+‐ATPases, the presence of nucleotides is required. Our results suggest that Cu+ loading of the TM‐MBS occurs in a sequential manner, in which after metal binding to one of the two sites, ATP binding is necessary to make the second site accessible for chaperone‐bound Cu+. This is in sharp contrast with "classical" P‐type ATPases, such as the Ca+2‐ATPase, in which ion uploading is independent of ATP binding. This work was supported by NSF grant MCB‐0743901.
A novel biological synthesis and purification of lipid A precursors
Authors: Metzger Louis Eugene , Raetz Christian R. H.
Published: June 2021

Gram‐negative bacteria possess an asymmetric outer membrane in which the outer leaflet contains both phospholipids and lipopolysaccharide (LPS). LPS forms a structural barrier that protects Gram‐negative bacteria from antibiotics and other environmental stressors. The lipid A anchor of LPS is a glucosamine‐based saccharolipid that is further modified with core and O‐antigen sugars. In addition to serving a structural role as the hydrophobic anchor of LPS, lipid A is recognized by the innate immune system in animal cells and macrophages. In macrophages, lipid A has been found to stimulate TLR4 (toll like receptor 4), which in turn activates the inflammatory cascade. Given lipid A's role in both pathogen viability and virulence, the genetic engineering of Gram‐negative bacteria to produce non‐canonical lipid A may play an important role in the development of attenuated vaccine strains. Here, we engineer E. coli to produce a non‐canonical lipid A precursor, 2,3‐diamino‐2,3‐dideoxy‐D‐glucopyranose lipid X. We then purify this compound from bacterial homogenate, verify its structure, and evaluate the specificity of various orthologues of LpxB, the bacterial lipid A disaccharide synthase, toward this non‐canonical substrate. This study presents the first biological synthesis and purification of this lipid A precursor. Funding: NIH 5R01GM0531310‐15 to CR and NSF GRF2005029353 to LM.
Differential Rac activation by major and minor group rhinovirus results in altered MAPK activation and cytokine release from human macrophages
Authors: Schreiber Michael , Schuler Bryce , Hall David J
Published: June 2021

Viral respiratory infections are a major cause of asthma exacerbations and can contribute to the pathogenesis of asthma. Major‐ and minor‐group human rhinoviruses (HRV) enter cells by binding to the cell surface molecules ICAM‐1 and LDL‐R that are present on epithelial cells and macrophages. The focus of the resulting viral infection is in bronchial epithelia. Despite this, previous studies of HRV infection and subsequent cytokine dysregulation have implicated macrophages as playing a role in establishing the inflammatory environment seen in HRV infection and asthma exacerbation. We demonstrate that the small molecular‐weight G‐protein Rac is differentially activated by the binding of major‐ and minor‐group rhinovirus to macrophages, that MCP‐1 release differs between the two viruses, and that inhibition of Rac attenuates the activation of the stress kinase p38 and the release of MCP‐1. Interestingly, RANTES release is not affected by Rac inhibition. This is the first report of a relationship involving major‐ or minor‐group HRV exposure, small molecular‐weight G‐protein activation, MCP‐1 release and macrophages, suggesting that Rac plays a role in establishing the inflammatory microenvironment initiated in the human airway upon exposure to rhinovirus. This work was supported by the Wriston scholarship, NIH R15 AI065505‐01A1 and NSF 0521112.
β‐Carotene content of novel orange‐fleshed honey dew ‘Orange Dew’ melons
Authors: Fleshman Matthew K , Lester Gene , Harrison Earl H
Published: June 2021

'Orange Dew' (OD) melon is a cross between orange‐fleshed cantaloupe (CAN) and green‐fleshed honey dew fruits. CAN has a rough, netted peel while honey dew has a smooth peel. OD fruit have both orange flesh like CAN and a smooth peel like honey dew. The smooth peel facilitates surface cleansing of microbes, and the orange flesh is an indicator of the presence the β‐carotene. We compared the β‐carotene content of OD and a CAN grown under the same glasshouse conditions. All melon plants were grown in well fertilized soil. Fruits at harvest were puréed and frozen (‐80 oC) until analysis. Percent dry weights were obtained, and β‐carotene concentrations were determined by HPLC. In vitro digestion was performed to determine percent digestive stability and percent micellerization of β‐carotene. The micelles were then applied to Caco‐2 cells to determine percent cell uptake (absorption). The average β‐carotene concentrations (µg/g dry weight) for the OD and CAN were 243 and 176, respectively. The average dry weight per gram of wet weight of OD and CAN was 0.09g and 0.07g respectively. Both mean β‐carotene content and dry weight of the OD were significantly greater than that of CAN (p‐values<.001). There were no differences in digestive stability, micellerization, or extent of cell uptake between the two fruits. However, the OD melons are both safer and contain more β‐carotene than CAN. Supported by USDA & NIH‐HL049879.
Canola oil inhibits human breast cancer cell growth by regulating caspase‐3 and p53
Authors: Park Chung S. , Cho Kyongshin , Mabasa Lawrence , Fowler Andrea W.
Published: June 2021

Epidemiological studies indicate that consuming a high‐fat diet may be correlated with an increased risk of breast cancer in women. However, increasing evidence suggests that it is not the quantity of fat but the type of fat intake that influences breast cancer risk. It is also suggested that the protective effect of omega‐3 fatty acids on breast cancer risk depends on the level of omega‐6 fatty acids, with a recommended omega‐6 to omega‐3 fatty acids ratio at 2:1 or lower. Canola oil has one of the lowest levels of saturated fat (7%, about half the level present in corn oil, olive oil and soybean oil). It has a relatively high level of oleic acid (monounsaturated fatty acid, 62%) and omega‐3 fatty acids (alpha‐linolenic, 10%) compared to most vegetable oils. It is thought that the low saturated fat, high oleic acid, and relatively high omega‐3 fatty acids content in canola oil give it particularly healthful properties. To investigate the effects of canola oil on breast cancer cell growth and apoptosis, two estrogen receptor‐positive breast cancer cell lines, T47D and MCF‐7, as well as a normal mammary cell line, MCF‐10A, were cultured and cell proliferation, caspase‐3 and p53 activities were measured. Canola oil supplementation significantly inhibited the growth of both T47D and MCF‐7 cell lines, but not MCF10A cell line. Canola oil also significantly increased the expression of p53, a tumor suppressor gene involved in cancer cell death, as well as the activity of caspase‐3 enzyme, one of the crucial enzymes regulating apoptosis pathway. Dietary strategies for cancer prevention and therapy are low‐risk and cost‐effective. Therefore, these results could be useful in the development of improved nutritional strategies for breast cancer prevention and therapy to reduce breast cancer risk. Supported by USDA‐CSREES (#2007‐38624‐18602).
Inhibition of Cellular Mediated LDL Oxidation by Select Sorghum Brans
Authors: Garner Pamela L , Hartle Diane K , Hargrove James L , Greenspan Phillip
Published: June 2021

Certain sorghum brans contain significant levels of phenolic compounds. Sumac and shanqui varieties are enriched with proanthocyanidins while black sorghum contains high levels of anthocyanins. We examined the effect of extracts (10% w/v in 50% ethanol) of six sorghum brans on the oxidation of LDL (100 µg protein/ml) mediated by J774 macrophages in Ham's F‐10 culture medium for 18 hr. When the extracts were presented to macrophage cultures at a concentration of 0.05% (v/v), three varieties significantly inhibited oxidation of LDL (sumac > shanqui > black) as measured by TBARS formation. Three other varieties (fontanelle, mycogen and white) were rather low in phenolic content and did not produce significant inhibition. When the extract of sumac sorghum was set at 0.02 % (v/v), LDL oxidation was inhibited by approximately 50%. The greater inhibitory effect of sumac and shanqui sorghum brans on LDL oxidation when compared to black sorghum bran may be a result of the capacity of these select sorghum brans to precipitate LDL, rendering it unavailable for oxidation. Ethanolic extracts of wheat, rice and oat brans did not inhibit the oxidation of LDL. These results demonstrate that phenolic compounds in select sorghum brans can significantly inhibit cellular oxidation of LDL (Supported by grant #5854304363 from the USDA)
Clofibrate induces expression of hepatic genes encoding fatty acid oxidation and ketogenesis enzymes in pigs during early postnatal development
Authors: Shim Kwanseob , Xi Lin , Jacobi Sheila , Odle Jack
Published: June 2021

The objective of this study was to evaluate the effects of clofibrate on gene expression of hepatic fatty‐acid‐oxidation and ketogenesis enzymes induced in pigs during neonatal development. Evaluations were conducted in 0, 1, 4 and 7 d‐old pigs fed milk replacer and orally gavaged with either vehicle (2 % Tween 80) or clofibrate (75 mg /kg body weight) +/‐ etomoxir (5 mg/ kg body weight). Transcript abundances were measured using qRT‐PCR and were greater for carnitine palmitoyltransfersae I (CPT I; 2.8 fold), carnitine palmitoyltransfersae II (CPT II; 3.1 fold), and mitochondrial 3‐methly‐3‐hydroxyglutaryl‐CoA synthase (mHMG‐CoA‐S; 3.9 fold) in pigs fed clofibrate verses vehicle. Addition of etomoxir had no effects on the transcript abundances induced by clofibrate. Transcript abundance of targeted genes also increased as piglets aged, but the mRNA levels remained relatively constant for CPT I and mHMG‐CoA‐S in pigs after 4 d and for CPT II after 1 d. There was no interaction between clofibrate treatment and age. The abundance of acyl‐CoA oxidase and peroxisome proliferator‐activated receptor αtranscripts were not altered by clofibrate, etomoxir or piglet age. In conclusion, clofibrate strongly induces genes of fatty acid oxidation in the young, postnatal pig, but induction is not influenced by developmental age. Supported by CSREES, USDA NRI program award 2007‐35206‐1 7897.
Effect of blueberries on the immune response of obese mice induced by high fat diet
Authors: Wu Dayong , Ren Zhihong , DeFuria Jason , Obin Martin , Meydani Simin Nikbin
Published: June 2021

Both high fat diet and obesity have been linked to impaired cell‐mediated immune response. Blueberry, rich in antioxidant phytochemicals, has been shown to impact biologic functions in several tissues. However, no information is available on immune cells. We investigated whether blueberry consumption affects immune response in obese mice induced by high fat diet. C57BL/6 mice were fed one of the 3 diets: low fat (LF), high fat (HF), or high fat plus 2% (w/w) blueberry (HF+B), for 8 or 12 wk. After 8 and 12 wk, both HF groups had higher body weight than the LF group and at 12 wk HF+B group had a higher body weight than the HF group. Lymphocyte proliferation responding to T cell mitogen Con A or PHA, or anti‐CD3/CD28 was not different at 8 wk but significantly lower at 12 wk in both HF groups compared to the LF group (HF>HF+B>LF). At 8 wk, the LF group had a lower IL‐4 and higher prostaglandin (PG)E2 production compared to both HF groups. At 12 wk, compared to LF group, HF but not HF+B group had lower IL‐4 and interferon‐γ production and contrary to reports in other tissues, both HF groups had lower production of IL‐1β, IL‐6, and TNF‐α indicating that obesity‐induced inflammation is tissue specific. While PGE2 production was similar between LF and HF groups, it tended to be lower in HF+B group. No difference in IL‐2 and IL‐10 production was found at either time points. In summary, HF impairs T cell proliferative response and addition of blueberries does not intervene in this effect. The high fat‐induced T cell‐suppressive effect may be related to the lower production of inflammatory cytokines. Supported by USDA #58‐1950‐7‐707 and the US Highbush Blueberry Council.
Snacking is associated with improved Healthy Eating Index (HEI‐2005) scores in adolescents aged 12‐18 years: NHANES, 1999‐2004
Authors: Keast Debra Rose , O'Neil Carol E. , Nicklas Theresa A.
Published: June 2021

The aim of this study was to examine the association of snacking with diet quality in adolescents aged 12‐18 years (n = 5,811). Snacks/drinks were combined when eating occasions were named in the 24‐h recall, but analysis separated snacks from snacks/drinks that were only drinks. Adolescents were classified by frequency of snack consumption (0, 1, 2, 3, 4+ snacks per day), and by % of daily energy intake obtained from snacks (0, <10, 10‐19, 20‐29, 30‐39, 40% or more). Diet quality was assessed using the Healthy Eating Index (HEI‐2005) with component scores determined by dietary intakes of macronutrients, sodium, and MyPyramid food groups per 1,000 calories. Energy intake increased, but energy‐adjusted intakes of total fat did not differ, carbohydrate was positively associated, and sodium was inversely associated with snacking frequency and percentage of energy from snacks. HEI‐2005 components improved with snacking included total and whole fruit, total and whole grain, healthy oils, and sodium; the solid fat, alcohol, added sugars score did not differ, but the meat & beans score was decreased with snacking frequency and with intake of calories from snacks. Snackers eating 2+ snacks per day, and snackers having <40% energy from snacks had higher total HEI‐2005 scores than non‐snackers. Snacking in moderation is associated with improved diet quality among adolescents in the U.S. Supported by Frito Lay and USDA
Weekend and Weekday Eating Patterns in Puerto Rican Schoolchildren Participating or Not Participating in the School Lunch Program
Authors: Preston Alan M , Rodriguez Cindy , Vazquez Quinones Luis , Venegas Heidi
Published: June 2021

Number of eating occasions and meal patterns can have marked implications on the nutritional quality of children's diets. Various factors such as financial resources and mother's employment status have been examined by the Continuing Survey of Food Intake by Individuals (CSFII)and have been reported for children. We have examined additional factors ‐ those of participation in the School Lunch Program and weekday vs weekend eating patterns. To accomplish this, we have performed 24 hr recall studies with children at 3 school levels: elementay (n=101), intermediate (n=115) and high school (n=105). We have further analyzed eating patterns on the basis of gender and of median body mass index (BMI). Results show that the mean number of eating occasions to be higher in participants (P) than in non‐participants (NP, to be higher in elementary school which lowers further in intermediate thru high school and to be higher in weekdays vs weekends. Number of occasions exceeded 4 per day for all groups. It would appear that participation in the Lunch Program is related to a higher number of eating occasions per day. This suggests positively that meal skipping is less however this might also raise the risk of overconsumption. Supported by the USDA‐CSREES‐NRI, award #2003‐35200‐13590.
The CDC and IOTF cut points show inconsistent prevalence of underweight and overweight in Chinese, Indonesian, and Vietnamese children
Authors: Nguyen Tuan T , Nicklas Theresa A.
Published: June 2021

No nationally representative data from middle and low income countries have been analyzed to compare prevalence of underweight and overweight defined by the Centers for Disease Control and Prevention (CDC) and the International Obesity TaskForce (IOTF) BMI cut points. We evaluated the consistency in nutrition status classifications derived from the CDC and IOTF cut points, using data from 1600 Chinese, 11756 Indonesian, and 53826 Vietnamese children aged 2‐18 y, who participated in recent, representative surveys in China, Indonesia, and Vietnam. A smaller difference between prevalence and a higher Kappa statistic indicated a higher consistency level between the CDC and IOTF classification systems. The prevalence of underweight defined by the IOTF was higher compared to those defined by the CDC cut points (absolute differences were 6, 10, and 13% in Chinese, Indonesian, and Vietnamese boys; 10, 13, and 19% in girls). Kappa statistic values were largest in Chinese boys (0.81‐0.88) compared to those in Indonesian (0.74‐0.82) and Vietnamese (0.69‐0.79) boys. Smaller Kappa statistics were found in girls from China (0.65‐0.80), Indonesia (0.63‐0.76), and Vietnam (0.55‐0.68). With an increase in age, Kappa statistics tended to increase in boys and decrease in girls. The differential findings from the CDC and IOTF cut points suggest that a validation of the cut points by using disease risk or body fat outcomes is needed. Supported by the Vietnam Educational Foundation (VEF) and USDA.
Attention, hemoglobin, and anthropometric measures in infants in southern Ethiopia
Authors: Thomas David G. , Schrader Sarah , Grant Stephanie , Eldridge Devon , Kennedy Tay , Rweuzala Pascasia , Berhanu Getenesh , Hambidge Michael
Published: June 2021

This study's purpose was to assess the relation of infant attention to hemoglobin (Hb) and general nutritional status as measured by weight‐for‐age (WAZ), length‐for‐age (LAZ), and head circumference (HCZ); z‐scores based on WHO standards. 82 infants from rural southern Ethiopia were given 6 toys to explore for 3 min at age 6 and 9 months. Measures of attention were total looking duration, mean look length, attention shifts, number of looks away, total duration of inattention, and mean length of inattention periods. Mean Hb levels were 11.66 and 11.61 g/dl at 6 and 9 months, range = 6.00‐15.40. At 9 months the 4 nutritional variables significantly predicted average length of looks to the toys (p =.016, R2 =.145). Hb (rp = .29, p =.01) and HCZ (rp = .23, p =.042) were the best single predictors. Attention shifts were also predicted by the nutritional variables (p =.037, R2 =.123) particularly Hb (rp =‐.23, p =.038) and HCZ (rp = ‐.24, p = .032). 6 month nutritional variables did not predict attention at 9 months. Better nourished infants may develop attentional control earlier than undernourished peers. (Supported by NIH Grant R21 TW06729, Office of Dietary Supplements & NSF Grant No. SES‐0552839).
The role of methionine metabolism in inflammatory bowel disease
Authors: Benight Nancy Marie , Stoll Barbara , Puiman Patrycja , Burrin Doulgas
Published: June 2021

Methionine (Met) cycle activity is critical for normal cell functions. Met metabolites S‐adenosylmethionine (SAM) and methylthioadenosine (MTA) are anti‐inflammatory, yet their role in inflammatory bowel disease (IBD) is poorly understood. We hypothesize that active IBD leads to changes in Met metabolites that impact disease and administration of SAM and MTA will reduce inflammation.

Study 1 mice received either a control diet (C) or a B6/B12‐deficient diet (D) to disrupt Met metabolism. Mice in both groups were challenged with dextran sulfate sodium (DSS) at 5% acutely or 2.5% chronically. Study 2 mice fed the C diet were then pretreated with control, SAM or MTA supplemented water for 7 days. During days 3‐7, all mice were received 3% DSS. We measured weight change, clinical disease activity index (DAI) and collected colon for analysis in both studies.

Study 1 mice fed the C diet had a higher mortality rate of 87.5% after 5% DSS when compared to D diet fed mice 37.5%. Similar results were seen with the 2.5% DSS (25% in C vs. 0% in D) and D diet fed mice had reduction in DAI compared to C fed mice. In Study 2, the MTA group had lower DAI and weight loss. No difference was detected in molecular markers or histology in either study.

Met cycle disruption via B‐vitamin deficiency and supplementing MTA were protective during colitis. We postulate that Met metabolites are modulating colonic inflammation. Funded by USDA.
Chemical variance of dry beans determined from UV spectral fingerprints
Authors: Harnly James M , Luthria Dave , Pastor‐Corrales Marcial S
Published: June 2021

The chemical variance of dry beans arising from three locations (Maryland, Michigan, and Nebraska), 9 varieties, 8 row samples, and triplicate determinations was determined from UV spectral fingerprints analyzed by analysis of variance‐principal components analysis (ANOVA‐PCA). Samples were extracted with 60% aqueous methanol, diluted as appropriate, and spectra (200‐400 nm) acquired by UV spectrophotometry. The data were analyzed using nested one‐way ANOVA where classic single variables were replaced by the sum of results for all wavelengths (200 variables). ANOVA‐PCA allowed pretreatment of the data matrix (648 samples x 200 wavelengths) to yield separate sub‐matrices isolating each experimental factor (location, variety, and row). Visual and statistical interpretation was easily accomplished. The results showed that, for 25 plants per row, 0.3% of the total variance came from location, 10.2% from variety, 70.8% from plant‐to‐plant variation, and 0.9% from analytical uncertainty.

This research was funded by USDA and the Office of Dietary Supplements at the National Institutes of Health.
Landscape genetics of white‐tailed deer in Illinois: a tool for investigating an outbreak of chronic wasting disease
Authors: Kelly Amy Catherine , Mateus‐Pinilla Nohra , Douglas Marlis , Douglas Michael , Ruiz Marilyn , Beissel Tom , Shelton Paul , Novakofski Jan
Published: June 2021

Understanding transmission patterns of wildlife diseases can facilitate predictions of disease spread and allow for identification of risk factors for disease. The objective of this study was to infer population structure and animal movement from genetic information to clarify the relative contribution of direct and environmental components of Chronic Wasting Disease (CWD) transmission. CWD, a cervid transmissible spongiform encephalopathy, was identified in Illinois in 2002 and is currently being managed through disease surveillance and increased population control. Multi‐locus genotypes were compiled for > 1000 white‐tailed deer sampled through CWD surveillance in Illinois. Using ten microsatellites, inter‐individual genetic relatedness values were calculated for CWD positive deer and for negative deer selected to control for gender, age and harvest location. No differences in genetic relatedness were observed between the two groups, suggesting that contact with relatives does not increase the rate of CWD transmission. Genotypes were further evaluated for genetic isolation by distance to infer gene flow and migration, information which could aid in the prediction of CWD spread across the landscape. Within the seven county study area of northern Illinois, female deer exhibited genetic isolation by distance while male deer did not. Research funded by USGS and IDNR.
Evidence for interaction between endothelin receptors in equine airways
Authors: Venugopal Changaram , Mariappan Nithya , Koch Catherine , Holmes Earnestine
Published: June 2021

Endothelin‐1 (ET), an inflammatory mediator, causes potent contraction of airway smooth muscles leading to oxidative stress (OS) by binding to ETA and ETB receptors. We investigated the interaction between the ETA and ETB receptors in contractions and OS on healthy equine bronchial rings. Rings were prepared from right diaphragmatic lobe. Rings for response studies were set in the tissue chambers containing oxygenated Tyrode's solution at 37oC and 2‐gm tension was applied. Concentration‐response relationships were determined with graded concentrations of ET‐1 on control rings, rings incubated with ETA and ETB antagonists, separately and combined. For OS studies, each ring was incubated for 30 min separately with ET, ET+ETA antagonist, ET+ ETB antagonist and ET+ ETA+ETB antagonists. Total reactive oxygen species (ROS), superoxide production and peroxynitrate were determined using Brucker EMX ESR spectrophotometer. ET caused dose‐dependent contraction which was enhanced by ETA blockade and was decreased by ETB blockade. Combined blockade significantly inhibited the response by ET. ET‐induced total ROS was decreased in all treatments. Superoxide production was slightly decreased by antagonists individually but increased when combined. Peroxynitrate production was increased by ETA antagonist, but decreased in other treatments. The study suggested that an interaction between ET‐receptors exists both in contractile response and OS. Supported by USDA Formula Funds (# LA 1433) and EHSP of LSU‐SVM.
α1‐Adrenergic Receptor Modulation of LPS Induced Inflammation in Normal and PMA Differentiated THP‐1 Cells
Authors: Grisanti Laurel A , Porter James E
Published: June 2021

Catecholamines released from the sympathetic nervous system in response to stress or injury, impact expression of inflammatory cytokines generated by immune cells. Adrenergic receptors (AR) have been shown to be expressed on various immune cell populations, but have not been well characterized. A human monocytic cell line, THP‐1 and phorbol 12‐myristate 13‐acetate (PMA) differentiated THP‐1 cells were used to measure expression of an inflammatory mediator interleukin‐1β (IL‐1β) responding to α1‐AR activation in the presence or absence of lipopolysaccharide (LPS). We hypothesized that stimulation of α1‐ARs expressed on immune cells modulates IL‐1β production. Binding studies characterized a homogenous population of α1‐ARs on THP‐1 cells, which changed to a heterogeneous population upon differentiation into macrophages. IL‐1β production in response to LPS was higher in the presence of α1‐AR activation, which was also observed for macrophages. Increased p38 activation was seen with concurrent phenylephrine (PE) and LPS stimulation, which resulted in NF‐κB activational changes. Blocking p38 and PKC activation inhibited the synergistic increase in IL‐1β production observed with LPS and PE treatment. This study demonstrates that α1‐ARs are present on both monocytic and monocyte derived macrophage cells and represents a mechanism by which innate immune responses can be modulated by adrenergic input. Funding: NSF Grant 0235146
β1‐Adrenergic Receptor Activation Potentiates a Pro‐Inflammatory Response in Human Monocytes
Authors: Grisanti Laurel A , Evanson Janel , Jorissen Heather , Porter James E
Published: June 2021

Increased circulating catecholamines released from the sympathetic nervous system, selectively activate immune cell receptors, modulating their inflammatory response to stress, injury or environmental toxins. Human monocytic THP‐1 cells were used to measure expression of inflammatory mediators responding to β‐adrenergic receptor (AR) activation in the presence or absence of lipopolysaccharide (LPS). Results from antibody arrays demonstrated that effective concentrations of the selective β‐AR agonist isoproterenol (Iso) synergistically increased LPS‐mediated expression of interleukin‐1β (IL‐1β) in THP‐1 cells. Selective kinase inhibition demonstrated that this β‐AR‐mediated, synergistic IL‐1β response signaled through activation of cAMP‐dependent protein kinase A. Radioligand binding studies further characterized a heterogeneous β‐AR population expressed on these same cells. Schild analysis demonstrated that only the β1‐AR subtype was responsible for generating cAMP in response to Iso. Furthermore, discerning concentrations of subtype‐selective β‐AR antagonists revealed that β1‐AR subtype activation facilitated this potentiated increase in IL‐1β production. Synergistic pro‐inflammatory responses in THP‐1 cells mediated by β1‐AR subtype coupling to cAMP‐dependent protein kinase A, represents a mechanism by which autonomic outflow could modulate immune function in vivo. Funding: NSF Grant 0235146
Lipopolysaccharide upregulates the expression of prolylcarboxypeptidase in endothelial cells
Authors: Kolte Dhaval Sanjeev , Ngo My‐linh ‐ , Mahdi Fakhri ‐ , Shariat‐Madar Zia ‐
Published: June 2021

Increasing evidence suggests that infection and other proinflammatory agents upregulate bradykinin and kallikrein, thereby promoting the proinflammatory response. In this study, we focused on proinflammatory role of prolylcarboxypeptidase (PRCP) induced by lipopolysaccharide (LPS), which induces inflammatory kinins [bradykinin (BK)] and kallikrein on endothelial cells. PRCP activates prekallikrein (PK) to kallikrein leading to the generation of bradykinin (BK) from high molecular weight kininogen (HK). After treating endothelial cells with LPS at sublethal concentrations, the mRNA for PRCP and antigen increased. The generation of both kallikrein and BK were elevated by three fold, suggesting PRCP upregulation contributes to the risk of developing inflammation. This amplification might be an additional mechanism whereby PRCP promotes a sustained inflammatory response. The inhibitor of PRCP and PRCP siRNA effectively attenuated the increase in kallikrein and BK generation on LPS‐treated endothelial cells. Taken together, these findings indicate that LPS at sublethal concentrations enhances PRCP‐dependent PK activation in endothelial cells. This study was supported by American Heart Association 0330193N, NCRR/NIH P20RR021929, and NSF MRI 0619774 ZS
Experimental gas embolism and tissue oxygenation using intravital microscopy
Authors: Torres Luciana N , Kanth Shreya , Torres Filho Ivo , Spiess Bruce
Published: June 2021

Little is known about microhemodynamic responses to arterial gas embolism (AGE) and associated local O2 tensions (PO2) have never been evaluated in vivo. Therefore, we assessed the adequacy of intravital microscopy to study the microcirculation during AGE, and investigated how bubble‐induced vaso‐occlusion and blood flow redistribution were associated with changes in arteriolar and tissue PO2. Blood pressure and heart rate were not significantly different before and after local AGE in the rat cremaster muscle. The first attempt of embolization did not result in arteriolar occlusion and multiple attempts were needed. Control diameter and blood flow averaged 53 ± 25 and 13 ± 10 nl/s, respectively. After AGE, these parameters changed to 53 ± 24 µm and 1 ± 3 nl/s. Arteriolar PO2 averaged 59 ± 19 mmHg during control and dropped to 34 ± 27 mmHg (upstream) and 24 ± 22 mmHg (downstream) after AGE. Interstitial PO2 changed from 44 ± 22 to 23 ± 20 mmHg and did not follow the drop recorded in the embolized arteriole when the PO2 in nearby flowing vessels remained high. We also measured in vivo bubble reabsorption (volume ≤ 20pL). Our findings suggest that blood redistribution in the muscle prevented severe hypoxia in some tissue areas after AGE and that arteriolar entrapment of air bubbles is associated with prior endothelial cell damage caused by the first bubble passage.

Support: NIH, ONR.
Python model of physiological and pathological hypertrophy
Authors: Secor Stephen M. , Riquelme Cecilia A. , Leinwand Leslie
Published: June 2021

As an integrative response to the prolonged metabolic demands of digestion, Burmese python (Python molurus) experience rapid growth of their heart. Within 3 days after feeding, pythons have experienced a 40% increase in cardiac mass. Deemed a physiological response to increase cardiovascular performance, the python's cardiac hypertrophy is characterized by an increase in mitochondrial volume and is sensitive to meal size and meal composition. Given that human heart disease is characterized by pathological cardiac hypertrophy, we explored whether we could induce pathological cardiac hypertrophy for the Burmese python using a modified version of transverse aortic constriction. We completely ligated the python's left aortic arch, thereby forcing all systemic blood flow into the right aortic arch and hence generating chronic ventricular pressure overload. Pythons suffered no ill effects from the ligation of their left systemic artery and were able to maintain adequate blood flow through the dorsal aorta. Preliminary examination revealed that ligation of the left systemic artery for 10 ‐ 200 days resulted in a 25% increase in ventricular mass. In addition, the ventricles of these snakes possessed a greater amount of fibrous tissue, a feature characteristic of pathological hypertrophy. We propose the python as a very attractive model to explore the underlying mechanisms of physiological and pathological cardiac hypertrophy. Supported by NSF IOS‐0466139 to SMS.
Changes in GDNF protein levels in the spinal cord with voluntary running
Authors: Czarnopys Monica J. , Spitsbergen John M.
Published: June 2021

GDNF strengthens and sustains synaptic connections at the neuromuscular junction. We have previously shown that low‐intensity exercise causes an increase in GDNF protein expression in skeletal muscles of rats. The purpose of the current study was to examine changes in GDNF protein content in the spinal cord from rats that have undergone voluntary exercise. Male Sprague Dawley rats aged 4 weeks were housed with continuous access to voluntary running wheels for 4 weeks. GDNF protein content of the spinal cord was measured using an enzyme‐linked immunosorbent assay. Immunohistochemical analysis was performed to localize GDNF in nerve cells in the spinal cord. The results show that GDNF protein can be detected in nerve cell bodies in the spinal cord; however, following exercise there was only a slight increase (not significant) in GDNF protein content in the spinal cord from exercised animals (842 pg/mg ± 146 pg/mg) compared to that in sedentary control animals (628 pg/mg ± 167 pg/mg). If GDNF protein expression is elevated with exercise, then this could help explain beneficial effects of exercise for motor nervous system in aging individuals or individuals suffering from Parkinson's disease and amyotrophic lateral sclerosis (ALS). This work was supported by NIH grant 1 R15 AG022908‐01A2, NSF grant DBI 0552517, Western Michigan University, and MSU‐KCMS.
Kinematic Analysis of Prey Capture Behavior in the Pond Turtle Pseudemys scripta elegans
Authors: Shanks Susan Elizabeth , Shanks Timothy William , Senseman David Michael
Published: June 2021

In pond turtles, visual tracking and prey capture is largely mediated by contractions of the neck musculature as a consequence of interactions between an upper motor system (optic tectum & reticular formation) and a lower motor system located within the cervical spinal cord (interneurons & motoneurons). Since the turtle eyes, brain and spinal cord can be maintained in vitro, prey capture offers an attractive experimental model in which to study the neuromechanics of a prehensile behavior at the cellular level. As part of this study, we used kinematic techniques to characterize feeding strikes of turtles attempting to catch small fish. To date, forty‐two strikes have been analyzed for one turtle. The maximum strike velocity observed was 329 mm sec−1 with an average velocity of 211+8 mm sec−1 (+ SEM). Immediately prior to the strike, the turtle's head was always observed at an intermediate point of extension, never fully retracted into the shell. This pre‐strike neck extension ranged between 29‐51 mm and averaged 41+1 mm. The neck extension at the end of the strike ranged between 49‐67 mm with a mean value of 60+1 mm. The change in neck length during the strike varied between 11‐30 mm with a mean value of 19+1 mm. Regression analysis showed that head velocity was positively correlated with the change in neck length and negatively correlated with the degree of pre‐strike extension. Supported by NSF UBM0634588.