bluuebunny/crossref_metadata_2025_split huggingface dataset:
C‐kit+ cardiac precursor cells exhibit a unique oxidant and antioxidant gene expression profile
Authors: Spealman Alyson Korry , Guruju Mallik , Poor Daniel , Sharma Ram V. , Kotlikoff Michael I. , Davisson Robin L. 
Published: June 2021

Evidence suggests that there are small populations of stem cells residing in the postnatal heart, and perhaps in the adult myocardium. Research from our laboratory demonstrates that c‐kit+ cells isolated from the hearts of c‐kitBAC‐EGFP mice can be expanded and differentiated in vitro into all three lineages of the heart. Since redox mechanisms play critical roles within stem cell niches, and also have distinct roles in cell signaling and death, we hypothesized that c‐kit+ cells exhibit a unique redox profile compared to control cardiomyocytes. Utilizing RT2Profiler PCR Arrays to investigate mRNA expression of 84 genes involved in oxidative stress and antioxidant defense, we found that 23 genes were upregulated and 4 genes were downregulated in c‐kit+ cells compared to controls. Upregulated genes included two superoxide dismutase isoforms (Sod1, Sod2), four members of the peroxiredoxin family (Prdx2, Prdx3, Prdx5, Prdx6), and myoglobin. The four downregulated genes included the third member of the Sod family (Sod3) along with apolipoprotein E, cytoglobin, and neutrophil cytosolic factor 2. Fold changes were considered significant at above 2‐fold and p<.05. These data reveal a unique redox profile in c‐kit+ cells, and may provide targets for improving survival, proliferation, and/or differentiation of these cells in vitro and, eventually, following cardiac damage in vivo.Grant Funding Source: HL063887, AHA 0540114N
Defining the Role of the Student Teaching Assistant in Gross Anatomy
Authors: Christensen Kevin Nicholas , Nyauncho Clive P , Hassinger James Peyton , Scoville Elizabeth , Kumar Neha , Pawlina Wojciech , Lachman Nirusha 
Published: June 2021

Teaching assistants (TA's) are an important resource in facilitation of 1st year courses at Mayo Medical School. Formal student teaching positions are available to 3rd students seeking opportunities to develop and refine peer teaching skills. While the Gross Anatomy course has traditionally utilized TA's as peer teachers the role of the TA has not been formally defined. Student evaluations as well as structured faculty and TA interviews were used to quantitatively assess how well TAs perceived their achievement of those goals compared to student and faculty perception. Expectations of TA's role include peer teaching through formal delivery of briefing sessions, group supervision during laboratory sessions, preparation of prosections, organization of review and informal practical examination sessions. TA's may extend their interaction with students through tutoring and participate in medical education‐based research projects. Furthermore, TA's are role players in assessment of student course performance. TA perception of their ability to meet expectations matched faculty and student perceptions. Student evaluations showed TA's to be one of the most highly rated resources in their teaching and learning and valued TA's for their capacity to relate to them, provide hands‐on clinical applications for basic science concepts, emotional support, time commitment to tutoring and assistance in the laboratory.Grant Funding Source: Mayo Medical School
Wnt/β‐catenin signaling represses heart muscle development via GATA transcription factors
Authors: Hoppler Stefan Peter , Lavery Danielle Lynn , Afouda Boni Anatole , Martin Jennifer 
Published: June 2021

Inhibition of Wnt/β‐catenin signalling is required in vertebrate embryos for initiation of heart development. The identity of the endogenous Wnt ligand that needs to be inhibited has so far remained unclear.We identified Wnt6 to be expressed close to the heart forming tissue in Xenopus. Endogenous Wnt6 expression is required during organogenesis to prevent differentiation of an abnormally large heart muscle. Even at these remarkably late stages, Wnt6/β‐catenin signalling regulates the pro‐cardiogenic transcription factor network rather than heart muscle differentiation directly.Our loss‐of‐Wnt6‐function experiments suggest a sequential deregulation of cardiogenic markers, with GATA genes deregulated earliest. We find that GATA genes are not only among the cardiogenic genes repressed by Wnt/β‐catenin signalling, but that reinstating GATA function experimentally will rescue subsequent heart muscle development. This result suggests that Wnt/β‐catenin signalling primarily restricts GATA expression in the cardiogenic mesoderm; and that where Wnt signalling does not repress GATA expression; GATA factors drive subsequent heart development.Wnt/β‐catenin is usually associated with transcriptional activation rather than repression. However, our recent experiments with protein‐synthesis inhibitor suggest that Wnt/β‐catenin is capable of repressing GATA gene expression directly.
Shape differences in the bony pelvis of women with and without pelvic floor disorders
Authors: Brown Kirsten , Handa Victoria , Macura Katarzyna , DeLeon Valerie 
Published: June 2021

Pelvic floor disorders (PFDs) include a suite of urinary and gastrointestinal tract problems that have a negative impact a woman's quality of life and effect up to one‐third of women. Earlier studies focused on width of the pelvis as a risk factor for PFDs. This is the first study to address the association of complex 3D pelvic shape with PFDs. We hypothesize that insertion sites of the muscular pelvic diaphragm are displaced further from one another in women with PFDs relative to unaffected controls. This study uses 3D geometric morphometrics to analyze the bony pelvis in a clinical sample of women with (n=6) and without (n=11) PFDs. Landmarks (k=41) were collected on pelvic reconstructions from MR data. Generalized Procrustes Analysis (GPA) and Euclidean Distance Matrix Analysis (EDMA) were used to localize shape differences between the control group and the affected group.GPA analysis identified significant shape differences between the two groups (α<.05); relative to other landmarks, the sacrum and ischial spines move posteriorly, and the iliac blades move medially and superiorly in women with PFDs. EDMA analyses demonstrated that the majority of differences between groups included the posterior displacement of the sacrum and antero‐posterior elongation of the birth canal. These results suggest that the posterior elongation of the pelvic diaphragm may be a better predictor of risk for PFD than pelvic width alone.Grant Funding Source: none
Myocardial BMP Can Promote Orientated Protrusion of the Proepicardium Necessary for Entry of Coronary Vessel Precursors and Epicardial Progenitors to the Heart
Authors: Garriock Robert John , Ishii Yasuo , Navetta Alicia , Mikawa Takashi 
Published: June 2021

The coronary vessel precursors and epicardium derive from a separate tissue rudiment outside of the heart called the proepicardium (PE). The PE protrudes to the heart and makes contact with the atrioventricular junction/inner curvature (AV/IC) region despite being closer to the sinoatrium. The attachment of the PE to the heart is an essential step in coronary vasculogenesis and formation of the epicardium. However, it is unknown how the specificity of PE attachment to the AV/IC is achieved. We demonstrate that BMP‐signaling from the myocardium specifies the attachment site of the PE to the heart. We show that Bmp2, which is expressed specifically at the AV/IC region of the heart, can signal alternative sites of PE attachment when misexpressed outside the AV/IC region. In contrast, misexpression of a BMP‐antagonist, Noggin, blocks PE attachment to the heart. Finally, PE explants preferentially protrude toward the AV/IC and this preference can be mimicked by BMP2/4. These results support a model in which BMP signals from the myocardium regulate PE protrusion and contact with a specific site on the heart.Grant Funding Source: NIH
Computational Analyses of Endocardial Cell Motion During Cardiovascular Morphogenesis in Transgenic Avian Embryos
Authors: Aleksandrova Anastasiia , Czirok Andras , Lansford Rusty D , Szabo Andras , Little Charles D , Rongish Brenda J 
Published: June 2021

Conventional dogma suggests that cardiac progenitors migrate to the midline to form a tubular heart, comprised of concentric myocardial and endocardial layers separated by extracellular matrix (ECM). Here we describe the motility of fluorescently tagged (Tie1‐YFP) endocardial progenitors in transgenic quail embryos using epifluorescent time lapse imaging. To visualize the extracellular matrix environment of migrating progenitor cells, we labeled fibronectin and fibrillin‐2 in vivo by microinjection of fluorochrome‐conjugated monoclonal antibodies. Imaging was performed at early stages, encompassing tubular heart assembly and early looping. We determined the relative importance of directed cell autonomous motility versus passive tissue movements in the assembly of a tubular heart. We established the motion of cells and fibrils of multiple ECM components using both object tracking and particle image velocimetry (image cross correlation). These quantitative data indicate the contribution of cell autonomous motility displayed by endocardial progenitors is limited. Thus tissue‐level motion drives most of the cell displacements during endocardial morphogenesis. Studies using motility inhibitors and Tie1+ cell transplantation will assess the role of myosin II‐dependent directed endocardial progenitor cell migration in early stages of tubular heart morphogenesis.Supported by NIH HL085694.Grant Funding Source: NIH HL085694
Ccr4‐Not complex directly regulates transcription elongation
Authors: Reese Joseph C , Kruk Jennifer A. , Dutta Arnob , Gilmour David S 
Published: June 2021

Many functions have been ascribed to the Ccr4‐Not complex. First described many years ago as a potential regulator of preinitiation complex (PIC) formation, more recently, a large body of evidence indicates it is predominantly cytoplasmic and regulates deadenylation of mRNA and ubiquitylation of substrates in the cytoplasm and nucleus. A direct role of this complex in transcription has not been demonstrated clearly, and the discovery of the cytoplasmic functions of this complex raises questions about how it regulates gene expression.Here we provide conclusive evidence that Ccr4‐Not directly regulates RNAPII transcription elongation. Ccr4‐Not associates with active genes in vivo, and it predominantly associates with the open reading frames of genes in a transcription and RNAPII‐dependent manner. We show that Ccr4‐Not regulates multiple elongation functions, and interestingly, mutation of different subunits of this complex results in distinct elongation phenotypes. Interestingly, Ccr4‐Not associates with RNAPII in a CTD‐independent manner in vitro and in vivo. Furthermore, using a highly purified system, we demonstrate that Ccr4‐Not associates with RNAPII elongation complexes and stimulates transcription elongation. Together, our results bring to light the functions of the Ccr4‐Not complex in the transcription cycle and provide evidence that it contributes directly to transcription by RNAPII.
Cellular Physiology of Bacterial Ribosome Assembly
Authors: Williamson James R. 
Published: June 2021

The bacterial ribosome is composed of 3 large RNA molecules and 53 small proteins. The biogenesis and assembly of ribosomes accounts for approximately one third of the energy budget for a rapidly dividing bacterial cell, and is thus a central aspect of cellular physiology. Not surprisingly, the high level of synthesis of the ribosomal components is subject to tight regulation to ensure coordinated production of each component in the required amount. While some general principles of feedback autoregulation have been identified, understanding of the network of regulatory interactions that coordinates ribosome assembly is very incomplete.We have developed a range of isotope pulse assays using 15N‐labeling to monitor ribosome assembly in rapidly growing E. coli. These experiments permit precise quantitation of free ribosomal protein levels, the levels of proteins in intermediate assembly particles, and the rate at which these particles turnover. Using chemical probes, protein overexpression, and analysis of deletion strains, we are developing a quantitative framework for understanding the process of ribosome biogenesis in bacteria.
The human milk microbiome: a potential influence on mammary health and bacterial colonization of the infant gut
Authors: Hunt Katherine Mary , Foster James A , Forney Larry J , Schütte Ursel M.E , Beck Daniel L , Williams Janet E , Collier Natalie N , McGuire Michelle K , McGuire Mark A 
Published: June 2021

Our study investigated the microbiome of healthy human milk collected aseptically from 16 women over a 5‐wk period. Bar‐coded 454 pyrosequencing of 16S rRNA genes produced an average of 4,000 reads per sample, with Streptococcus, Staphylococcus, and Corynebacterium identified as the dominant phylotypes at the genus level when evaluated using the Ribosomal Database Project classifier. The ACE richness metric estimated from 180 to 1,700 distinct phylotypes (97% similarity) in each sample. The community composition of milk collected from each woman was relatively consistent over time; nonetheless, although profiles from each woman tended to cluster together, random shifts occurred at some time points causing drastic changes in microbial community composition. Data reveal that complexity of the milk bacterial communities is comparable to that found on skin or in the mouth, but less complex than that in the gut. In summary, human milk harbors a wide variety of bacteria that appear to change in composition at times perhaps due to environmental characteristics in the mammary gland related to diet, milk composition, or immune factors. These bacterial communities may play pivotal roles in mammary health and colonization of the infant gut. Supported by NIH‐NRRI grants P20 RR15587 and P20 RR16448, and the United Dairymen of Idaho.Grant Funding Source: NIH‐NRRI grants P20 RR15587 and P20 RR16448, andthe United Dairymen of Idaho.
Non‐heme and heme iron absorption during pregnancy
Authors: Young Melissa F. , Griffin Ian , Pressman Eva , McIntyre Allison , Cooper Elizabeth , McNanley Thomas , Harris Leah , Westerman Mark , O'Brien Kimberly O. 
Published: June 2021

Iron homeostasis during pregnancy has important implications for dietary recommendations/interventions. Our objectives were to examine heme and non‐heme iron absorption in 20 pregnant (16–32 y) and 12 non‐pregnant subjects (18–27 y). The clinical study included a 2‐day iron absorption study where subjects were randomly assigned to receive a heme meal (intrinsically labeled 58Fe) and a non‐heme iron supplement (57Fe ferrous sulfate) on alternate days. After two‐weeks a blood sample was taken to assess iron status, serum hepcidin and iron absorption based on red blood cell iron incorporation. Heme iron absorption was significantly higher than non‐heme iron absorption in both pregnant (47.9 ± 14.4 vs. 40.4 ± 13.2%, p=0.02) and non‐pregnant subjects (50.2 ±14.8 vs. 15.3 ± 9.7%, p<0.0001). Pregnant women absorbed significantly more non‐heme iron (p <0.0001) but not heme iron compared to non‐pregnant women. Hepcidin was directly associated with serum ferritin (p=0.0001, p=0.03) and total body iron (p=0.03, p=0.0008) in pregnant and non‐pregnant women. Serum hepcidin was inversely associated with 57Fe enrichment (non‐heme meal) (p<0.05) and a similar trend was evident with 58Fe enrichment (heme meal) (p=0.08) in healthy pregnant women. Unlike non‐heme iron, heme iron absorption does not appear to be upregulated during pregnancy.Grant Funding Source: Cornell Univ. 2006‐07‐160, NIH Training Grant 5T32DK00715835, and ILS
Study of the acute impact of polyphenols from brown seaweeds on glucose control in healthy men and women
Authors: Lamarche Benoit , Paradis Marie‐Ève , Couture Patrick 
Published: June 2021

This study examined the acute impact of polyphenols from brown seaweeds on post‐load plasma glucose and insulin concentrations in healthy subjects. Twenty‐three participants (11 men, 12 women) aged 24–55 years were recruited in this double‐blind randomized placebo controlled study. The test product consisted of two 500mg capsules of InSea2™, a commercial mix of polyphenols from brown seaweeds with known inhibitory action on α‐amylase and α‐glucosidase activities. Polyphenol and placebo capsules were consumed on each occasion 30 minutes prior to consumption of 50 g of available carbohydrates from bread. Plasma glucose and insulin concentrations were measured over a period of three hours post carbohydrate ingestion at pre‐specified time points. Both treatments were separated by one week. Acute consumption of the seaweed polyphenol mixture was not associated with any adverse event. Compared with placebo, acute consumption of seaweed polyphenols was associated with a non significant 3.6% reduction in the area under the curve (AUC) of plasma glucose concentration (P=0.16), a 5.9% reduction in the insulin AUC (P=0.031) and a 6.9% increase in the Cederholm index of insulin sensitivity (P=0.047). Responses were similar in men and women. These data suggest that polyphenols from brown seaweeds may alter the acute glycemic and insulin response to carbohydrate ingestion.Funding: innoVactiv Inc.
Attenuation of common cold symptoms by encapsulated juice powder concentrate
Authors: Roll Stephanie , Nocon Marc , Willich Stefan N 
Published: June 2021

IntroductionDietary supplements have been suggested as preventive strategies for common cold, but previous results were inconsistent. This study aimed to assess the effect of a dietary supplement from fruits and vegetables on common cold symptoms in healthy healthcare professionals.MethodsThis was a randomized double‐blind placebo‐controlled trial. Subjects were taking four capsules of dietary supplement (Juice Plus+®) or matching placebo daily for eight months, including a two month run‐in period. We report means and 95% confidence intervals (CI) for the number of days with at least moderate common cold symptoms (primary endpoint) and number of days with any common cold symptoms. Differences between groups are analyzed with ANOVA.ResultsA total of 543 subjects were included, with 529 valid for primary analysis (intervention: 263, placebo: 266). The mean number of days with at least moderate common cold symptoms was 7.6 (95% CI 6.5–8.8) in the intervention and 9.5 (8.4–10.6) in the placebo group (P=0.023). The mean number of days with any common cold symptoms was 29.4 (25.8–33.0) in the intervention and 30.7 (27.1–34.3) in the placebo group (P=0.616).ConclusionIntake of a dietary supplement from fruits and vegetables was associated with a reduction of moderate or severe common cold symptoms, but not with a reduction of total days with common cold symptoms.Research support: NSA (TN, USA)
Effect on serum lipids and lipoproteins of diets enriched with a terrestrial (flaxseed) versus algal‐oil (V‐Pure®) source of n‐3 fatty acids in healthy adults
Authors: Wien Michelle , Oda Keiji , Rajaram Sujatha , Haddad Ella , Sabaté Joan 
Published: June 2021

BackgroundAlgal‐oil supplements usually contain only docosahexaenoic acid (DHA). The algal‐oil based V‐Pure® supplement contains both eicosapentanenoic acid (EPA) and DHA, thus mimics fish oil supplements. However, the effects of consuming V‐Pure® on serum lipids, lipoproteins, apolipoproteins and their corresponding ratios are unknown.Aim and MethodsTo compare the effect on serum lipids, lipoproteins and apolipoproteins of diets enriched with a terrestrial source (flaxseed oil) of α‐linolenic acid (ALA) versus V‐Pure supplement (S), we performed a randomized cross‐over study (3 8‐week study periods) in 24 healthy adults (mean±SE age 42±2.7 years). Under controlled feeding conditions, subjects consumed eucaloric diets [10:1 n‐6:n‐3 ratio (Control), 2:1 n‐6:n‐3 ratio (flaxseed oil, ALA; 6–7g/2400 kcal/d) and 10:1+S (0.20/0.72g EPA/DHA per 2400 kcal/d)]. A mixed model analysis was conducted.ResultsCompared to the Control diet, the 10:1+S diet produced an increase in total cholesterol (9.9±9.9 mg/dl), apolipoprotein B (ApoB) (5.3±5.0 mg/dl) and ApoB:ApoA1 (0.06±0.04) in the context of a 17.8±11.5 mg/dl decrease in triglyceride levels (all p<0.05).ConclusionConsumption of a 10:1 n‐6 to n‐3 diet plus an algal‐oil supplement containing both EPA and DHA results in contrasting lipid changes; however, consumption of a different source of n‐3 fatty acids (flaxseed oil) yielded neutral effects.
A factorial design feeding study to evaluate the effects of α‐linolenic acid (ALA) versus eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on serum lipids in healthy adults
Authors: Sabaté Joan , Wien Michelle , Rajaram Sujatha , Haddad Ella 
Published: June 2021

BackgroundModern diets have n‐6 to n‐3 ratios greater than 10:1, whereas some ancient diets contained higher levels of α‐linolenic acid (ALA) and a ratio of ~2:1. The benefit of taking supplements of eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) on serum lipids within these background diets is little known.Aim and MethodsA factorial design approach was used to test the overall diet effect (10:1 vs. 2:1), supplement (S) effect (±EPA/DHA) and potential treatment interaction on serum lipids. A randomized cross‐over feeding trial (8‐week periods) in 24 healthy adults was conducted. Subjects consumed eucaloric diets [10:1 (Control), 2:1 (ALA; 6–7g/2400 kcal/d), 10:1+S (0.20/0.72g EPA/DHA per 2400 kcal/d), and, 2:1+S].ResultsA decrease in total cholesterol (TC) [7.7±3.3 mg/dl (P<0.01)] and apolipoprotein B (ApoB) [2.7±1.5 mg/dl (P=0.04)] was observed in changing from a 10:1 to a 2:1 diet. Taking EPA/DHA decreased triglycerides 7.6±5.5 mg/dl and increased TC (8.0±3.3 mg/dl), HDL (3.0±1.0 mg/dl), LDL (6.2±2.9 mg/dl), ApoB (4.7±1.6 mg/dl) and ApoB:ApoA1 (0.03±0.01)(all P<0.001). A synergistic effect was found for TC:HDL, which decreased more than expected (P=0.01).ConclusionThe diet ratio and EPA/DHA supplement had distinct effects on serum lipids, and, synergistic effects occurred for TC:HDL, the clinical lipid parameter with the highest predictive value for cardiovascular risk.
Qualitative examination of cultural influences on diet and physical activity patterns among Latino WIC families
Authors: Kim Loan Pham , Harrison Gail , Whaley Shannon , Mallo Nelly , Jenkins Eloise 
Published: June 2021

Childhood obesity rates have risen sharply in the US in the past several decades, and at particular risk are immigrant Latino children who are twice as likely as African‐American or white children to be overweight. General consensus among researchers and practitioners is that dietary treatment of overweight in children alone is usually unsatisfactory. Prevention, beginning early in childhood through careful attention to both diet and physical activity and factors influencing these behaviors, is the only viable public health option. This qualitative study conducted: 1) 20 one‐on‐one interviews with WIC mothers of children 3–5 years of age, 2) 10 interviews with WIC para‐professional staff. Interviews were designed to elicit culturally relevant information to contribute to our understanding of the complex landscape in which childhood obesity exists by examining the physical environment of diet and physical activity behaviors, and the social environment in which cultural norms and beliefs influence perceptions, behaviors and practices. We will present salient elements, identified from this research, for developing effective childhood obesity prevention programs focusing on low‐income Latinos in California.Grant Funding Source: AMERICAN HEART ASSOCIATION #09PRE2390123.