bluuebunny/crossref_metadata_2025 huggingface dataset:
Probing the Interactions between α‐1, 4‐Mannobiose Molecules, using AFM
Authors: Perera Komitige Hashanthi , Basu Saswati , Chandran Preethi
Published: June 2021

Carbohydrate‐carbohydrate interactions (CCIs) have been recognized to govern a wide range of biological processes including species‐recognition, fertilization, embryogenesis, and cell development (1). The goals of our study are to investigate whether mannobiose moieties exhibit CCIs and to determine the solution conditions in which the interactions occur. Mannobiose moieties are disaccharides of mannose sugars. They coat the surfaces of pathogens and immune cells and are extensively involved in host‐pathogen interactions (2). The oligosaccharides are widely used in the design of drug‐delivery vehicles for targeting cells that express mannose receptors (e.g., dendritic cells) (2) and for reducing the cytotoxicity induced by the drug‐delivery vehicles (4). Therefore, the finding of CCIs between mannobiose moieties will impact the field of immunotherapy and the design of drug‐delivery vehicles.

CCIs between α‐1, 4‐mannobiose moieties were measured using the force spectroscopy (FS) mode of an atomic force microscope (AFM). The mannobiose molecules were covalently attached to thiolated linkers and assembled as monolayers on gold‐coated mica and AFM tips. The mannobiose exposure on these functionalized surfaces was verified by its selective binding of lectin concanavalin‐A. The strength of CCIs between the mannobiosylated surfaces was determined as a function of the monovalent and divalent ion concentrations in the solution, and of the pH. Control experiments were designed to measure the interactions between the thiolated linkers.

Our results indicate that there are self‐adhesive interactions between the mannobiosylated AFM surfaces. These interactions tend to be in the range of 200–800 pN, and predominantly occur as multiples of ~200pN. The addition of free mannobiose significantly diminishes the adhesive forces. We are currently investigating the effect of solution conditions on the magnitude of the interactions. The conclusion of our study is that mannobiosylated surfaces exhibit complex potential for interactions, which can be harnessed for the design of immunotherapies and of drug‐delivery vehicles.

Support or Funding Information

This material is based upon work supported by National Science Foundation under grant no. 1407891 awarded to Preethi Chandran and by a mini‐grant awarded to Preethi Chandran under NSF grant no. 1208880 (PI: Dr. Sonya Smith)
WWOX coordinates with type II TGF‐beta receptor in regulating cell‐to‐cell recognition and immune cell differentiation
Authors: Chen Yu‐An , Sie Yong‐Da , Lu Chen‐Yu , Chang Nan‐Shan
Published: June 2021

Tumor suppressor WWOX is anchored, in part, at the cell membrane/cytoskeleton area and is able to sense alterations of extracellular cues. By time‐lapse microscopy, we determined that WWOX plays an important role in controlling cell migration and cell‐to‐cell recognition. Wwox−/−MEF cells migrate individually; however, wild type Wwox+/+ MEF cells migrate collectively. When wild type Wwox+/+ MEF cells meet Wwox−/− cells, they fail to recognize each other. The knockout cells stretch out their pseudopodia to touch the wild type cells, and then move in a retrograde manner, followed by dividing immediately. The phenomenon is observed in many WWOX‐deficient cells upon encountering WWOX‐positive cells. By molecular dissection, an epitope of WWOX, namely WWgre (WWOX7–21), is responsible for attracting visiting cells. In contrast, SDRrepl (WWOX286–299) repels WWOX‐negative visiting cells. Specific antibodies against SDRrepl or WWgre block the cell‐to‐cell recognition effects. Both epitopes are physically associated with type II TGF‐beta receptor (TbetaRII). Accordingly, TGF‐beta and TbetaRII IgG antibody abolish the repellence effect. Notably, synthetic WWgre peptide is highly potent in causing T lymphocyte clonal expansion in the spleen, whereas pS14WWgre induces expansion of Hyal‐2+ CD3‐ CD19‐ (or Z) lymphocyte for memory anticancer response. Taken together, WWOX plays a crucial role in controlling cell migration, recognition, and immune cell differentiation.

Support or Funding Information

MOST and NHRI, Taiwan; DoD, USA.
The Effect of Y71 Mutants on The Allosteric Switch of Ras
Authors: Charley Kelsey , Guterres Hugo , Mattos Carla
Published: June 2021

Ras GTPase is involved in a number of signaling pathways that are responsible for the control of many cellular processes, including cell proliferation. Ras functions like a molecular switch, where its inactive form binds to GDP and its active form binds to GTP. We had shown through crystallography work that in its active form, Ras has two major conformational states, including the T‐state (tardy) and the R‐state (reactive). The R‐state is obtained through an allosteric modulation by the binding of calcium acetate in the crystal structure. Through a wild‐type accelerated molecular dynamics (aMD) simulation, we observed that residue Y71 is involved in the transitioning from R‐ to T‐state. In this study, we aim to elucidate the role of residue Y71 in the allosteric modulation of H‐Ras. We work to obtain the structure of Y71F and Y71A mutants of H‐Ras, and conduct aMD simulations for these mutants. For aMD simulation, we make Y71F and Y71A mutants using homology modeling of wild type H‐Ras structure. In lab, we made mutations using site directed mutagenesis and successfully mutate Tyrosine 71 to Phenylalanine and Alanine. We over‐expressed our mutants in Escherichia coli system, used ion exchange and gel filtration chromatography for protein purification. Our aMD simulation shows that Y71F and Y71A mutants changed the conformational balance between the R‐ and T‐states, favoring the T‐state, relative to wild type H‐Ras. We observe different dynamics in these two mutants, specifically Y71F show higher flexibility near the active site residues, relative to the wild type. Our preliminary crystallization result will also be presented. This study will help elucidate the role of a novel allosteric residue that will help in understanding the allosteric mechanism of H‐Ras.

Support or Funding Information

NSF MCB‐1244203.
Enhanced Cholesterol Clearance and Bile Acid Signaling in Skin‐Specific SCD1 Deficient Mice
Authors: Dumas Sabrina , Boehmer Robert , Ntambi James
Published: June 2021

Stearoyl‐CoA desaturase 1 (SCD1) catalyzes the rate limiting step in monounsaturated fatty acid synthesis by inserting a double bond at the delta‐9 position of long‐chain fatty acids. SCD1 converts stearate (18:0) to oleate (18:1n9) and palmitate (16:0) to palmitoleate (16:1n7). Global deletion of SCD1 in mice provides remarkable resistance to both high‐carbohydrate and high‐fat diet‐induced obesity. These mice also demonstrate improved insulin sensitivity and glucose clearance. Interestingly, skin‐specific deletion of SCD1 also provides protection from high‐fat diet‐induced obesity, and similar metabolic improvements. In addition, these mice have increased skin surface free cholesterol, decreased circulating total cholesterol and increased circulating total bile acids. Cholesterol is minimally lost by the skin, but this loss is upregulated in skin‐specific SCD1 deletion. Reduced circulating cholesterol is a well‐known cardio‐protective phenotype, whereas increased circulating bile acids are protective against weight gain via TGR5 signaling. TGR5 signaling is also related to improved insulin sensitivity. Importantly, cholesterol catabolism into bile acids is the major route of cholesterol excretion. Proteomic and genetic analysis of skin tissue of skin‐specific SCD1 deficient mice indicate upregulated TGR5 signaling, and increased cholesterol and bile acid biosynthesis.

Support or Funding Information

Sabrina Dumas was supported by USDA Hatch W2005.
Lead and cadmium levels in breast milk and maternal blood and their relation to inflammation markers
Authors: Zhong Yingyi , Kennedy Tay , Stoecker Barbara , Aubuchon‐Endsley Nicki L , Grant Stephanie , Hubbs‐Tait Laura , Thomas David G.
Published: June 2021

The heavy metals cadmium and lead are well known for their toxicity to the human body. They are carcinogenic and detrimental to multiple organs, including the brain. Various factors such as drinking water, cigarette smoke exposure, and environmental pollution can impact levels of cadmium and lead in nursing mothers, subsequently exposing their infants.

The objective of our study is to determine the relation between levels of cadmium and lead in maternal blood and breast milk and see whether these levels correlate with inflammation markers, including C‐reactive protein (CRP) and alpha‐1‐acid glycoprotein (AGP).

At 3 month postpartum, 132 primarily white mothers were recruited into our study. Breast milk and blood samples were collected on site using techniques designed to limit trace mineral contamination. Breast milk was manually expressed and later ashed before analysis. Both the breast milk and the maternal blood samples were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP MS). AGP and CRP, inflammation markers, and soluble transferrin receptors (sTFR) were measured using ELISA kits.

Lead and cadmium were positively correlated in both blood (r=0.297, p <0.01) and breast milk (r= 0.558, p<0.01).

Blood lead concentrations (m=4.96 μg/L, SD=4.11) were significantly greater than breast milk lead concentrations (m=1.85 μg/L, SD=2.12); p<0.001. Blood cadmium concentrations (m=789 ng/L, SD=564) were also significantly greater than those in milk (m=228 ng/L, SD=275); p < 0.001. The mean blood levels were two and half times the mean breast milk levels for lead and nearly three times the mean breast milk levels for cadmium.

Blood cadmium concentrations were positively correlated with blood CRP concentrations (r=0.287, p<0.001), while milk cadmium levels were negatively correlated with blood AGP concentrations (r=−0.201, p=0.023). In addition, blood lead concentrations were negatively correlated with sTfR concentrations (r=−0.203, p=0.022).

Maternal exposures to lead and cadmium contribute to lead and cadmium in breast milk which may impact their breastfed infants. Our results suggest these minerals may not be actively transported from blood to breast milk but that inflammation might affect the transport of these metals from the blood to breast milk.

Support or Funding Information

Supported by National Research Initiative Grant 2008‐35200‐18779 from the USDA National Institute for Food and Agriculture and an OSU Provost's Multidisciplinary Grant
HomeStyles: Strategies Used to Retain Parents of Preschool Children in a Long‐Term Randomized Control Trial
Authors: Delaney Colleen , Martin‐Biggers Jennifer T , Koenings Mallory , Tonnessen Rebecca , Byrd‐Bredbenner Carol
Published: June 2021

Randomized control trials (RCTs) are the gold standard in scientific research. Keeping participants actively involved throughout the RCT is critical to success, yet little is published with regard to retention strategies. Thus, this abstract describes the strategies used in the 18‐month HomeStyles childhood obesity prevention RCT to retain parents of preschoolers. Retention strategies included 1) high‐quality, attractive, quick and easy to use intervention materials (i.e., guides) responsive to the wants and needs of parents of preschoolers in written in Spanish and English; 2) flexible 24/7 participation opportunities (e.g., web delivery; online data collection) and implementing strategies to minimize participant burden; 3) elements of surprise, such as sending fun, unexpected guide‐related enhancements (e.g., beach ball, hula hoop) and holiday or reminder cards in eye‐catching mylar envelopes; 4) program identity branding of all RCT materials using the colorful HomeStyles logo to remind parents about the project each time they noticed project materials in their homes or received electronic or mailed items; 5) financial stipends in the form of eGift cards to participants’ favorite stores immediately after completion of RCT questionnaires and opportunities to receive earn extra stipends (e.g., bonus bucks for visiting the website frequently, submitting supplementary data including height, weight, and pedometer readings); 6) consistent contact methods in the form of frequent, friendly, positive multi‐mode communication including messages in the form of encouraging and motivating nudges sent every ~4 days via email, SMS, and/or voice mail, and protocols to reach out to participants by phone, email, and mail as soon as they showed signs of inactivity; 7) immediacy, ease, and consistency, such as making communication with the RCT team easy (toll‐free phone, email) and replying rapidly to participants queries by trained staff using uniform procedures and consistent messaging; 8) English‐ and Spanish‐speaking study personnel; 9) effective research management with trained RCT team members, established protocols for all RCT procedures, frequent monitoring of participant activity and rapid application of retention procedures; 10) providing an equivalent control group intervention (Home Safety) and not labeling this group as “control”; 11) nonfinancial incentives encouraging participants to make small changes towards their goal to maintain confidence and manage stress and reminding parents to keep the goal of an even happier, healthier family at the forefront as they worked to make improvements; 12) ability to easily update contact information each time participants logged on to the project website. The retention procedures used in this RCT have the potential to improve RCT retention in a broad range of nutrition education research studies.

Support or Funding Information

USDA NIFA #2011‐68001‐30170
The Modulatory Effect of Common Dietary Fatty Acids on IPEC‐J2 Transport of Lipopolysaccharide and Monolayer Barrier Integrity in vitro
Authors: Lyte Joshua Mark , Gabler Nicholas K , Hollis James H
Published: June 2021

Recent evidence has demonstrated the ability of dietary fatty acid composition to influence postprandial endotoxemia in humans and swine. However, the mechanism(s) by which fatty acids affect transport of lipopolysaccharide (LPS) across the intestinal epithelium has not yet been fully elucidated. To study this, we utilized non‐transformed porcine jejunum‐derived IPEC‐J2 cells. This cell line is well‐recognized to form confluent polarized monolayers with apical and basolateral regions, allowing for an in vitro model of the intestinal epithelium. The present study investigated the effect dietary fatty acids and inflammation had on intestinal permeability of LPS and barrier integrity in IPEC‐J2 monolayers. We hypothesized that treatment of IPEC‐J2 monolayer with saturated or n‐6 polyunsaturated fatty acids (PUFA) would enhance fluorescein‐isothiocyanate (FITC)‐LPS apical‐to‐basolateral permeability and reduce transepithelial resistance (TER); whereas n‐3 PUFA would attenuate this response. Secondly, we hypothesized that lauric acid would amplify the reduction in monolayer integrity associated with pre‐treatment with LPS. IPEC‐J2 cell monolayers were grown to confluency (>1kΩ) on 0.4 μm Transwell® inserts. In experiment 1, these monolayers were treated with either 50 or 100 μM of docosahexaenoic acid, lauric acid, arachidonic acid or vehicle for 48 hours before TER and FITC‐LPS determination of barrier integrity. In experiment 2, monolayers were treated with either 5 μg/mL LPS, LPS plus 100 μM lauric acid or saline vehicle for 24 hours and then TER and FITC‐LPS determination of barrier integrity assessed. In experiment 1, TER and FITC‐LPS permeability was not altered by fatty acid type or concentration. For experiment 2, compared to the saline control, LPS caused a significant time‐dependent reduction in TER (p<0.001); however, the co‐inclusion of lauric acid fatty acids did not have any additive effect on TER (p>0.05). Although TER was reduced, surprisingly we reported no treatment differences in apical to basolateral FITC‐LPS permeability. In conclusion, fatty acid treatment did not modulate barrier inflammation and permeability in in vitro IPEC‐J2 monolayers. However, live Gram‐negative bacteria or their bacterial cellular membrane fragments may be a better model to study the effects of fatty acids on LPS permeability.

Support or Funding Information

Research supported by the Agriculture and Food Research Initiative Grant No. 2014‐67017‐21778 from the USDA NIFA.
Test‐retest reliability and postprandial time course of the neural responses to visual food stimuli
Authors: Sayer R Drew , Tamer Gregory , Chen Ningning , Tregellas Jason , Cornier Marc , Kareken David , Talavage Thomas , McCrory Megan , Campbell Wayne
Published: June 2021

The brain's reward system influences ingestive behavior and subsequently obesity risk. Functional magnetic resonance imaging (fMRI) is a common method for investigating brain reward function. We sought to assess the test‐retest reliability and postprandial time course of neural responses to visual food cues using fMRI. A priori brain regions of interest included bilateral insula, amygdala, orbitofrontal cortex, caudate, and putamen. Fasting‐state fMRI and appetite assessments were completed by 29 overweight or obese women (n=17) and men (n=12) on 2 days for test‐retest reliability analyses determined by intraclass correlation coefficient. A subset of 3 women and 4 men completed postprandial fMRI and appetite assessments 0, 90, 180, and 270 min after consuming a 300 kcal meal to document the postprandial time course of responses. Mean fasting‐state neural responses on Day 1 and Day 2 were not different in 8 of 10 regions of interest. However, test‐retest reliabilities of neural responses were mostly poor or unreliable. Only the left orbitofrontal cortex response demonstrated fair test‐retest reliability. Furthermore, neural responses to visual food stimuli were largely unaffected by meal consumption. In conclusion, fMRI‐measured responses to visual food cues in overweight and obese adults show relatively good group‐level reproducibility but considerable within‐subject variability and are insensitive to meal consumption.

Support or Funding Information

American Egg Board, NIH UL1 TR001108, USDA‐NIFA 2011‐38420‐20038, Purdue University Ingestive Behavior Research Center
Effects of Higher Dietary Protein and Fiber Intake at Breakfast on Postprandial Insulin and Glucose Responses in Overweight Adults
Authors: Amankwaah Akua , Sayer R Drew , Wright Amy J , Chen Ningning , McCrory Megan A , Campbell Wayne W
Published: June 2021

Background

Dietary protein and fiber independently influence insulin‐mediated glucose control. However, the potential additive or synergistic effects of higher protein and fiber intake on postprandial insulin and glucose responses are not known.

Purpose

This study assessed the effects of protein and fiber intakes at breakfast on postprandial insulin and glucose responses.

Methods

Men and women [n = 20; age: 26 ± 5 y; body mass index: 26.1 ± 0.2 kg/m2; means ± SEM] consumed provided breakfast meals with varying protein (high = 25 g vs. normal =12.5 g) and fiber (high= 8 g vs. normal = 3 g) amounts during 4, 2‐week interventions (randomized crossover experimental design). Each 2‐week period was separated by a 2‐week washout period. The breakfast variations included: normal protein and fiber (NPNF), normal protein and high fiber (NPHF), high protein and normal fiber (HPNF), or high protein and fiber (HPHF). Breakfast was provided with fixed energy (400 kcal) and digestible carbohydrate (50 g) on each day, and the remainder of daily energy intake was self‐selected. On the last day of each intervention period, a meal tolerance test was completed to assess serum glucose and insulin concentrations at fasting and hourly for 4 hours (240 min). Repeated measures ANOVA was applied for data analyses.

Results

There were no differential responses among breakfast meals on composite postprandial insulin and glucose (240‐min total areas under the curve (AUC)) after adjusting for fasting values, sex, and breakfast treatment order. Analysis of the 0–120 min and 120–240 min AUCs supported that higher protein and/or fiber did not influence glucose responses. Further, differential responses were not observed for insulin AUC at 0–120 min but were for 120–240 min. The 120–240 min insulin AUC was numerically lowest after NPHF (880 ± 103 μU/mL) and was statistically different from HPNF (1228 ± 104 μU/mL) but not HPHF (1004 ± 104 μU/mL) or NPNF (1049 ± 108 μU/mL).

Conclusion

Doubling the amount of protein from 12.5 g to 25 g/meal and increasing fiber from 3 to 8 g/meal did not additively or synergistically affect postprandial insulin and glucose responses. These results do not support increasing dietary protein and fiber at breakfast as an effective strategy for modulating insulin‐mediated glucose responses in young, overweight adults.

Support or Funding Information

Support: American Egg Board‐ Egg Nutrition Center; NIH UL1TR0001108; USDA‐NIFA 2011‐38420‐20038
Associations between serum leptin, iron status, and dietary iron intake in young adults
Authors: McClung James P. , Lutz Laura J. , Hennigar Stephen R. , Karl J. Philip , Cable Sonya J. , Cropper Thomas L. , Gaffney‐Stomberg Erin
Published: June 2021

Leptin,a hormone secreted by adipose tissue, is a regulator of energy intake and expenditure. Iron, an essential micronutrient, functions as a cofactor for proteins and enzymes involved inoxygen transport and energy metabolism. Dietary iron intake and adipocyte iron levels have been recently demonstrated to suppress leptin expression in animals. Additionally, recent studies indicate aninverse association between serum leptin and serum ferritin (SF) in humans, independent of body mass. However, associations between iron status and serum leptin have not been examined in healthy young adults. As such, the objective of this study was to explore relationships between serum leptin, iron status indicators (SF, soluble transferrin receptor[sTfR], transferrin saturation [TS], hemoglobin, and hepcidin), and dietaryiron intake in young adults (n = 513, males = 306, females = 207, age[mean ± SE] = 20.6 ± 0.1 yrs, body fat = 17.4 ± 0.5 %). Biomarkers were assessed in blood from fasted volunteers; dietary iron intake was assessed using food frequency questionnaires. Univariate line arregression indicated negative correlations (P < 0.05) between serum leptin and SF (r = −0.26), TS (r = −0.21), hemoglobin (r = −0.36), and hepcidin (r =−0.09), and a positive association (P < 0.05) between serum leptin and sTfR(r = 0.10). In fully adjusted (age, body fat percentage, inflammation, and race) linear regression models, serum leptin and hemoglobin were positively associated (P < 0.05) in men (β ± SE = 0.07 ±0.02), but not women (β = 0.01 ± 0.02), whereas serum leptin and dietary iron intake were negatively associated (P < 0.05) in men (β = −0.53 ± 0.24), but not women (β = 0.25 ± 0.21). Associations between serum leptin and other iron status indicators were not statistically significant in either sex in fully adjusted models. Taken together, these data suggest that associations between serum leptin, iron status, and dietary iron intake are not independent of body fatness in young adults. Future studies conducted in large cohorts with individuals with varying body composition are required to elucidate the potential link between iron status and appetite regulation.

Support or Funding Information

Research supported by USAMRMC.
Amelioration of Cardiometabolic Risk Factors With a Pecan‐rich Diet in Overweight and Obese Adults
Authors: McKay Diane L. , Eliasziw Misha , Chen C‐Y Oliver , Blumberg Jeffrey B.
Published: June 2021

Evidence from in vitro and observational studies indicates tree nuts may reduce the risk of cardiovascular diseases (CVD) and type 2 diabetes mellitus (T2DM), though support from controlled feeding trials is limited. Most nut intervention studies to date have counseled subjects to incorporate nuts into their usual diet, an approach that can neither control for inter‐individual variability in the background diet, nor fully account for the intake of other food/beverage components that can influence CVD and T2DM risk, e.g., antioxidants, fatty acids, and fiber. We conducted a 12 wk randomized, controlled, cross‐over feeding trial to examine the effects of pecans in overweight and obese men and postmenopausal women ≥45 y with central adiposity. Subjects (n=25) were randomized to either a diet resembling the average American diet (control) or the same diet with whole pecans (intervention) incorporated at ~15% of energy (1.5 oz/2000 kcal) for 4 wk, and then the opposite diet for the final 4 wk. Total fat and fiber in these isocaloric diets were similar, and all meals/snacks were provided. During the 2 wk run‐in and 4 wk washout periods, subjects were counseled to consume the control diet. A multivariate multilevel model was used to simultaneously analyze change in z‐scores of insulin, glucose, total cholesterol, triglycerides, and LDL. An interim analysis (n=18) yielded a mean increase of 0.11 SD in the control arm and a decrease of 0.23 SD in the intervention arm (mean difference between arms = 0.34 SD, P=0.047). Although differences in favor of the intervention arm were observed for all individual cardiometabolic risk factors, the sample size was too small for them to reach statistical significance. Preliminary evidence suggests a pecan‐rich diet may have a benefit in modifying cardiometabolic risk factors.

Support or Funding Information

Supported by USDA and the National Pecan Shellers Association
Effectiveness of the Compensatory Reserve Index in Monitoring Blood Resuscitation in Baboons
Authors: Hinojosa‐Laborde Carmen , Nguyen Betty , Mulligan Jane , Grudic Greg , Convertino Victor
Published: June 2021

BACKGROUND

The Compensatory Reserve Index (CRI) is a machine learning algorithm that detects the body's ability to compensate for blood loss by analysing changes in arterial waveforms. Previous studies have shown CRI to be more accurate than traditional vital signs in estimating an individual's risk of hemodynamic decompensation. However, the effectiveness of the CRI in monitoring volume resuscitation has not been evaluated. The purpose of this study is to assess the ability of CRI to detect volume resuscitation incomparison to traditional vital signs.

METHODS

This study compared systolic arterial pressure (SAP), heart rate (HR), stroke volume (SV), and CRI during whole blood resuscitation after 25% blood volume hemorrhage in baboons (n=12). The study was conducted at the Texas Biomedical Research Institute (San Antonio, TX)under an approved protocol by their Animal Care and Use Committee. Statistical analysis was performed using two repeated measures ANOVA and linear regression analysis.

RESULTS

SV, SAP, HR, and CRI were all sensitive to blood resuscitation. SV and SAP overshot baseline during resuscitation, but CRI did not. Target SAP for resuscitation is 80–90 mm Hg. The corresponding CRI value was approximately 0.25–0.30, which aligns with the transition from an unstable to a moderately compromised condition.

CONCLUSIONS

CRI can detect not only hemorrhage, but also blood resuscitation in baboons. CRI is equally effective as traditional vital signs for detecting blood resuscitation. The ease of tracking CRI makes it a potentially effective clinical tool for monitoring blood resuscitation.

Support or Funding Information

FUNDING: US Army Medical Research and Materiel Command Combat Casualty Care Research Program
Predicting salt and diuretic sensitivity in a virtual population using topological data analysis
Authors: Clemmer John S. , Pruett W. Andrew , Hester Robert L.
Published: June 2021

Salt sensitivity, with or without concomitant hypertension, is associated with increased mortality. In the clinical setting, determining salt‐sensitivity in patients is laborious and an expensive challenge with low patient compliance. A large subset of salt‐sensitive patients with hypertension are known to be resistant to diuretic therapy. Personalized medicine distinguishes specific subpopulations to better manage individual patients, but this concept has not been adequately applied to the treatment of hypertension. We hypothesized that topological data analysis (TDA) of physiological responses to salt loading in a computer‐generated cohort can predict patient salt‐sensitivity and responses to thiazide therapy. Using HumMod, an integrative mathematical model of human physiology, we studied the chronic blood pressure response to salt loading (500 mMol/day for 2 weeks) in a heterogeneous population of 4000 virtual patients created by varying cardiovascular and renal system parameters. A binned clustering algorithm distinguished salt‐sensitive ( >6 mmHg change in blood pressure after salt loading) and salt‐insensitive patient populations. One cluster of patients in the salt‐sensitive population, characterized by lower plasma sodium and glomerular filtration rate at baseline, had significantly greater fall in blood pressure in response to thiazide administration (−5.6±0.2 vs. −4.5±0.2 mmHg) which was associated with a blunted activation of the renin‐angiotensin system. We also determined that following an acute water loading simulation, urine volumes and salt output correlate with physiological sensitivity to high salt intake and diuretic therapy. This data suggests that TDA of physiological behavior in human populations could be used as a predictive tool and improve personalized medical treatment.

Support or Funding Information

Supported by the National Science Foundation under Grant No. NSF EPS‐0903787 and the NIH P01 HL 51971.
Effects of Tolvaptan on Mechanosensory Primary Cilia
Authors: Sherpa Rinzhin T , Nauli Surya M
Published: June 2021

Primary cilia are non‐motile sensory extensions present in a variety of cells. Over the past decades, studies have shown to associate the pathology of polycystic kidney disease (PKD) to defective in mechanosensory primary cilia (ciliopathy). We have previously shown that improving cilia length can enhance mechanosensory cilia function, which we termed “ciliotherapy”. Because tolvaptan is seen to be a potential therapy in PKD, we tested the hypothesis that tolvaptan can alter cilia length or function. In the present study, mouse and porcine renal tubule cells were grown to confluent monolayer. Once differentiated, tolvaptan was added to culture plates to achieve desired concentrations. Cilia length and function were measured with standard microscopy techniques using acetylated‐α‐tubulin and Fura‐2AM, respectively. Tolvaptan at 0.1 μM optimally increased cilia length and function. Cell cycle analysis showed no significant differences between control and tolvaptan treated cells. In summary, our studies indicate that tolvaptan may have a positive therapeutic effect on cilia function.

Support or Funding Information

Department of Defense (PR130153)
An Experimental Test of Colony Size Effects on Mass‐Specific Metabolic Rate in a Social Insect
Authors: Waters James S , Ochs Alison , Toth Jack , Fewell Jennifer H. , Harrison Jon F.
Published: June 2021

The metabolic costs of being an organism generally scale hypometrically, such that per‐gram metabolic rates decrease with increasing size. The drivers of this almost universal feature have yet to be clearly identified. Cohesive social groups, particularly the social insects, also show hypometric scaling with colony size. It is not known whether size is a causal factor or whether this relationship is only a correlation. We experimentally reduced the size of harvester ant colonies (Pogonomyrmex californicus), to test whether colony size is causally responsible for large colonies utilizing less energy per gram. We identified three potential parameters, all related to the organization of the work, that are candidate mechanisms for driving hypometric scaling of metabolism. Larger colonies had lower median (but not average) walking speeds, and more ants classified as stationary, potentially reducing locomotory costs. Larger colonies had reduced mass‐specific perimeters of the brood pile, consistent with reduced per‐capita brood rearing, a potentially expensive task. Finally, larger colonies had reduced network density and centrality, consistent with greater division of labor, specialization, and segregation of individuals, which may reduce metabolic costs by improving efficiency. A simulation model suggests that simple behavioral rules may cause reduced network densities that could reduce colonial metabolic rates by promoting specialization in task performance and activity levels.

Support or Funding Information

This research has been supported by Providence College, the James S. McDonnell Foundation, and the National Science Foundation under Grant No. 1110796.
Doublet Potentiation During In Vitro Cyclical Movement of Mdm Mouse Muscles
Authors: Enright Dory , Monroy Jenna A , Nishikawa Kiisa
Published: June 2021

It has been observed that the addition of a stimulus (doublet) to a train of stimuli increases the force output of muscles, and that the effect of a doublet on force diminishes as muscle length increases. In natural movements such as running, muscles are activated at various lengths during cyclical motion. Thus, the increase in force due to the addition of a doublet during cyclical movements likely depends on the length at which a muscle is stimulated during the cycle (i.e. phase of activation). Recent work has suggested that the elastic protein, titin, may play a role in doublet potentiation. Using the muscular dystrophy with myositis (mdm) mouse, which is characterized by a deletion in the N2A region of titin, we investigated the role of titin in doublet potentiation during work loop experiments. We measured force output of soleus muscles from wildtype and mdm mice subjected to cyclical changes in length and stimulated at various phases. The length and force data were used to construct work loops, which were integrated to determine the work output of each muscle. Results show that the addition of a doublet increased muscle work at lower stimulation frequencies (p < 0.0001), and that at these same frequencies the relative increase in work was greater in wildtype compared to mdm muscles (p = 0.0003). In addition, both genotypes showed the largest increase in work when stimulated at the shortest lengths, and the smallest increase when stimulated at the longest lengths (p < 0.0001). These interactions between activation and length suggest that elastic elements play a role in doublet potentiation. Our work is consistent with the winding filament hypothesis, which suggests that titin contributes to active muscle force.

Support or Funding Information

This work was funded by the Anderson Endowment at Denison University, an APS UGSRF award to D.E.E., and NSF 1456868.
Maternal High Fat Diet Increases an Inhibitory Extrasynaptic Tonic GABAA Current in Dorsal Motor Nucleus of the Vagus Neurons Regulating Gastric Functions
Authors: McMenamin Caitlin A , Browning Kirsteen N
Published: June 2021

The perinatal period is critically important in the development of autonomic neurocircuits innervating the gastrointestinal (GI) tract influencing gastric emptying and appetite regulation. Developmental alterations may affect these GI neurocircuits possibly contributing to the energy imbalance seen in obesity. Previous studies suggest there is an increased GABAergic inhibition of gastric projecting dorsal motor nucleus of the vagus nerve (DMV) neurons in the brainstem of rats fed a high fat diet (HFD) during the perinatal period, but the underlying neural mechanisms and the effects on gastric motility have yet to be clarified. The aims of this study was to assess the effects of perinatal HFD on (i) inhibitory synaptic inputs to gastric‐projecting DMV neurons and (ii) gastric tone and motility.

Whole cell patch clamp recordings were made from gastric projecting DMV neurons in thin brainstem slices from Sprague‐Dawley rats (4–6 weeks of age) fed either a control or HFD (14 or 60%kcal from fat, respectively) from embryonic day 13.

In the present study, perinatal HFD rats were not significantly heavier than age‐matched control rats (6 weeks; 232±17g vs 209±5g). Superfusion with the non‐selective GABAA receptor antagonist, bicuculline (50μM), induced a larger inward current in DMV neurons from perinatal HFD vs control animals (55.7±14.1pA vs 21.7±1.7pA, n=8, P<0.05), suggesting a greater overall tonic inhibition. While superfusion with the phasic (synaptic) GABAA receptor antagonist, gabazine (25μM), did not reveal any difference in the resulting inward current between perinatal HFD vs control DMV neurons (11.2±1.4pA vs 6.7±1.5pA, n=6, P>0.05), the addition of bicuculline into the bath uncovered a larger tonic (extrasynaptic) GABAA current in perinatal HFD vs control DMV neurons (36.4±3.47pA vs 20.8±2.24pA, n=6, P<0.05), suggesting that the greater overall inhibition of perinatal DMV neurons results from a larger tonic GABAA current.

The studies imply that perinatal overnutrition increases the tonic GABAergic inhibition of gastric projecting DMV neurons via an increase in activation of extrasynaptic GABAA receptors. Such alterations in brainstem neurocircuit development as a consequence of maternal over‐nutrition may induce gastric dysmotility and dysregulated gastointestinal reflexes, hence influence offspring to develop obesity.

Support or Funding Information

Funded by NIH 078364 and NSF IOS1148978
Stress and Traumatic Brain Injury Elicit Similar Cytokine Responses in Blood and Liver
Authors: Mayer Thomas A , Audet Gerald N , Scrimgeour Angus G
Published: June 2021

Mildtraumatic brain injury (mTBI) is a major health issue comprising aheterogeneous and complex array of pathologies. Little is understood about the mechanisms of secondary injury in the evolution of damage after mTBI; however an apparent hepatic‐neural communication may generate a systemic inflammatory response (SIR). A stress‐mediated release of cortisol and catecholamines can enhance the SIR, leading to immunological dysfunction causing a retardation of healing in brain and systemic infrastructure. This study investigated the role of the SIR after TBI in male Wistar rats (N=129) that were subjected to one of four different procedures: mild TBI, moderate TBI, stress with mild TBI, or stress with sham TBI. Stress was generated using immobilization‐restraint tubes for 2 hours per day for the 4 days prior to injury. TBI was induced using a 500g weight‐dropmethod (from 100cm height for mild injury; and 120cm for moderate injury). Rats were sacrificed 6 hours, 48 hours, or 14 days after TBI or sham procedure. Serum corticosterone remained significantly elevated at 14‐days post‐injury. In order to correlate circulating inflammatory responses with liver specific responses, a panel of cytokines(e.g. IL6, TNFα, IFNγ, etc.) and SIR‐associated proteins (e.g. VEGF, TIMP, ICAM, etc.) were analyzed in liver tissue as well as in serum. Overall, we detected few differences in cytokine expression across the various experimental procedures or time‐pointsin serum or liver tissue (e.g. liver IFNγ at 48hr A.U.: modTBI 0.43±0.19;mildTBI 0.48±0.11; mildTBI w/stress 0.52±0.15; shamTBI w/stress 0.36±0.10; p=0.88). Thus, it appears that the SIR may not play a significant role in mild TBI pathology, specifically as it pertains to common circulating and hepatic cytokine pathways. Funded by USAMRMC. Author views not official US Army or DoDpolicy.
Quantification of javamide‐I and ‐II in twelve coffee drinks and their effects on sirtuin1/2/3 enzymes and p53‐acetylation in THP‐1 cells.
Authors: Park Jae
Published: June 2021

Coffee is one of most consumed drinks worldwide. Javamide‐I (N‐coumaroyltryptophan) and‐ II (N‐caffeoyltryptophan) are phenolic amides found in coffee. However, the amounts of javamide‐I and‐ II have not been determined in daily consumed coffee drinks, and their effects on sirtuin1/2/3 enzymes are still unknown. Therefore, in this paper, javamide‐I and ‐II were isolated and quantified from coffee using a HPLC method, and their effects on sirtuin1/2/3 enzymes were studied. First, the chemical structures of isolated javamide‐I and‐ II were unambiguously confirmed using NMR spectroscopic methods. Then, their amounts were determined in 12 different coffee samples prepared using five beans, four ground and three instant coffees. Javamide‐I and ‐II were detected in some coffee samples at the ranges of 0.04–2.31 mg/g. Using javamide‐I and ‐II isolated from coffee, their effects on sirtuin1 (nuclear), sirtuin2 (cytoplasm) and sirtuin3 (mitochondria) were investigated in vitro. Javamide‐II showed higher inhibition activity against sirtuin1 (IC50 of 30 μM), 2 (IC50 of 8 μM) and 3(IC50 of 61 μM) than javamide‐I. Especially related to sirtuin2, javamide‐II exhibited noncompetitive inhibition of sirtuin2 with Ki = 9.6 μM. In a docking simulation, javamide‐II showed stronger binding pose to sirtuin2 than EX527. Also, javamide‐II was able to increase total acetylation levels and the acetylation of p53 in monocytic THP‐1 cells. In addition, differential effects of javamide‐I and ‐II analogues on inhibiting sirtuin1/2/3 will be also discussed in this study.

Support or Funding Information

USDA
Maternal Lipid‐based Nutrient Supplements (LNS) Did Not Reduce Depressive Symptoms During Pregnancy and Lactation in Rural Bangladesh
Authors: Matias Susana L , Mridha Malay Kanti , Khan Showkat Ali , Hussain Sohrab , Siddiqui Zakia , Vosti Stephen , Arnold Charles D , Dewey Kathryn G
Published: June 2021

Background

Maternal depression is a major global burden affecting not only women but also their children. Maternal intake and serum levels of polyunsaturated fatty acids have been inconsistently associated with reduced perinatal depression.

Objective

We aimed to determine the effects of lipid‐based nutrient supplement (LNS), containing macro and micronutrients, including essential fatty acids (4.6 g of linoleic acid and 0.6 g of alpha‐linolenic acid), on maternal depressive symptoms at 36 weeks of gestation and 6 months postpartum.

Methods

We conducted a cluster‐randomized effectiveness trial in Bangladesh (the Rang‐Din Nutrition Study), where women received either iron & folic acid (IFA) or LNS during pregnancy and the first three or six months postpartum, respectively. Maternal depressive symptoms were assessed by trained interviewers using a validated Bangla version of the Edinburgh Postnatal Depression Scale (EPDS‐B) at 36 weeks of gestation (n=2937) and 6 months postpartum (n=3510) at local antenatal clinics. Outcomes included the EPDS score (range: 0–30) and prevalence of depressive symptoms, defined as an EPDS score ≥10.

Results

Overall median (interquartile range) EPDS scores were 2 (0–4) and 1(0–3) at 36 weeks of gestation and 6 months postpartum, respectively. Prevalence of reported maternal depressive symptoms was low in this population (2.1% at 36 weeks of gestation and 2.7% at 6 months postpartum). Cluster‐adjusted intention‐to‐treat analyses indicated no significant differences by treatment group in EPDS scores (square root back transformed Means ± SEs; 36 weeks of gestation: 1.4 ± 0.1 vs 1.5 ± 0.1 in the LNS and IFA groups, respectively, p=0.22; 6 months postpartum: 1.2 ± 0.1 vs 1.3 ± 0.1 in the LNS and IFA groups, respectively, p=0.12) or prevalence of depressive symptoms (36 weeks of gestation: 2.5% in the LNS and 2.0% in the IFA group, p=0.42; 6 months postpartum: 2.8% in the LNS and 2.6% in the IFA group, p=0.68). Per‐protocol analysis including only those who consumed the supplements regularly indicated lower EPDS scores in the LNS compared to the IFA group at 36 weeks of gestation (1.2 ± 0.1 vs 1.5 ± 0.1, respectively, p=0.01). No other significant differences by treatment group were observed in per‐protocol results.

Conclusion

In Bangladesh, maternal LNS did not show an effect on reported depressive symptoms in late pregnancy and at 6 months postpartum. Reports of depressive symptoms in this population were less common than in other populations in Bangladesh, which may have limited our ability to detect effects of LNS.

Support or Funding Information

U.S. Agency for International Development (USAID)'s Food and Nutrition Technical Assistance (FANTA) III Project, managed by FHI 360.
Regulation Of Homologous Recombination: Robustness Through Reversibility
Authors: Heyer Wolf‐Dietrich
Published: June 2021

Homologous recombination is a critical pathway to maintain genome stability. The signature reactions in recombination of homology search and DNA strand invasion are carefully regulated. The Rad51‐ssDNA filament, which conducts the homology search, exists in a balance between assembly and disassembly, where specific motor proteins, such as Srs2 in yeast, lead to disassembly of the filament. This process reverses Rad51 filament formation as a mechanism of anti‐recombination. A second mechanism of anti‐recombination is the disruption of the primary DNA strand invasion product, the nascent D‐loop. While it has been thought that the disruption of D‐loops is being conducted by motor proteins and helicases, we showed that nascent D‐loop dissolution by Top3‐Rmi1 represents a distinct mechanism of anti‐recombination. Another level of regulation affects the outcome of recombination, the formation of crossover or non‐crossover products. The Synthesis‐Dependent Strand Annealing (SDSA) pathway of DNA double‐strand break repair envisions the disruption of the extended D‐loop after DNA synthesis to enable the annealing of the extended invading strand with the second end of the double strand break. Hence, different enzymes are needed to target the nascent D‐loop and the extended D‐loop to achieve anti‐recombination or anti‐crossover (= pro‐SDSA), respectively.

The model that homologous recombination proceeds as a pathway of successive metastable reversible intermediates has an interesting genetic implication that provides an additional mechanistic explanation for synthetic lethality between mutations in different genes. Eliminating forward and backwards steps in a single reversible pathway simultaneously may lead to trapping of a toxic intermediate or depletion of an essential compound. Such genetic interactions have been observed in the recombination pathway and are likely applicable to additional reversible pathways.

Support or Funding Information

We are grateful for the funding from the National Institutes of Health and the Department of Defense.