bluuebunny/crossref_metadata_2025 huggingface dataset:
The influence of different carbon sources on the structural characteristics of the bacterial cellulose membrane (1180.15)
Authors: Bravo Mariangela , Lazarini Silmara , de Carvalho Renata , Corbi Fabiana , Corbi Pedro , Lustri Wilton , Amaral André
Published: June 2021

Recent research shows that bacterial cellulose membranes (BCm), which represent a promising biomaterial for the use in regenerative medicine, can be used as biological support and/or as a system of extended release of bioactive compounds. The objective of this work was to characterize the influence of different carbon sources (CS1 and CS2), obtained from the processing of sugar cane, on the physical and structural characteristics of the BCm. To develop this work, bacterial strains of Gluconacetobacter hansenii (ATCC 23769 ) were cultivated in media containing nitrogen source (5,6g/L) and increasing concentrations of CS1 (2.5, 5 , 7.5, 10, 12.5 and 15%) and CS2 (5, 10, 15, 20, 25 and 30%). The static culture was maintained at room temperature for 14 days. The influence of the carbon sources and the different concentrations was established by analysis of dry matter yield, tumescence capacity and ultra‐structural analysis. The best yield was obtained with the mass concentration of 10% CS1 (0.71 g/L) and 15% CS2 (0.84 g/L) and percentage of tumescence of 70,7% and 71,6 % respectively. The ultra‐structural analysis of the BCm best yield in the two sources showed a difference among the reticular structures. It was concluded that carbon sources obtained from sugar cane provided, in the concentrations mentioned above, favorable conditions for the biosynthesis of BCm by G. hansenii, with potential for the use in regenerative medicine.

Grant Funding Source: Supported by: Conselho Nacional de Desenvolvimento Científico e Tecnológico ‐ CNPq
Polarized mechanotransduction in osteocytes: role of αVβ3 integrin on the cell processes (1180.9)
Authors: Thi Mia , Suadicani Sylvia , Schaffler Mitchell , Weinbaum Sheldon , Spray David
Published: June 2021

Osteocyte processes attach to the bony canalicular wall at discrete integrin sites and loading‐induced fluid flow in the lacunar‐canalicular system results in focally high membrane strains around these attachments, but not at the cell body. While the presence of integrin in the attachment sites to the canalicular wall suggests its participation in osteocyte mechano‐transduction, such a role still remains to be demonstrated. The goal of this study was to address these points by using the novel Stokesian fluid stimulus probe (SFSP) to achieve the spatial resolution required to stimulate MLO‐Y4 osteocyte processes and cell body with physiologically relevant hydrodynamic forces at pN levels. Ca2+ imaging studies demonstrated that osteocyte processes are uniquely mechanosensitive. 1‐5 pN level forces applied to the cell processes triggered Ca2+ signaling while comparable stimulation of cell bodies did not. Inhibition of αVβ3 integrin attachment sites with IntegriSense probe blocked the Ca2+ response to SFSP stimulation. Furthermore, we found that ATP is a major autocrine/paracrine signaling messenger that amplifies spread of Ca2+ signals from the mechanically stimulated process to cell body and from one osteocyte to another in the network. We thus validated the essential role of αVβ3 integrin on osteocyte processes in focal mechanosensing and transduction.

Grant Funding Source: Supported by AR057139, DK091466
Phosphorylation regulates clathrin‐mediated endocytosis of the thiazide‐sensitive cotransporter NCC (1181.12)
Authors: Rosenbaek Lena , Kortenoeven Marleen , Aroankins Takwa , Fenton Robert
Published: June 2021

Our recent work suggests that AQP2 endocytosis rates can be regulated via phosphorylation. As NCC is phosphorylated at conserved residues in its intracellular NH2 terminus, we hypothesized that a similar mechanism may regulate NCC plasma membrane abundance. Novel MDCKI cell line models stably expressing NCC were generated to examine trafficking pathways of NCC and the role of phosphorylation in regulation of NCC internalization. In MDCKI‐NCC cells, NCC was observed as a highly glycosylated monomer and dimer. NCC constitutively recycled to/from the apical plasma membrane of MDCKI‐NCC cells, with 20‐30% of the apical membrane pool of NCC being internalized within 30 min. Using specific inhibitors of either clathrin‐dependent or ‐independent endocytosis we determined that NCC is internalized via a clathrin‐mediated pathway and reduction of endocytosis results in greater steady‐state NCC levels in the plasma membrane. Inducing phosphorylation of NCC via low chloride treatment or mimicking phosphorylation by replacing Thr53, Thr58, and Ser71 residues with Asp, resulted in increased apical membrane abundance and reduced rates of NCC internalization. Our data support a model where NCC is constitutively cycled to the plasma membrane, where upon stimulation it can be phosphorylated resulting in increased NCC activity and decreased NCC endocytosis, which together increase NaCl transport in the DCT.

Grant Funding Source: Supported by Lundbeck Foundation and Danish Medical Research Foundation
Visualization of vectorial trafficking of aquaporin‐2 tagged with photoconvertible fluorescence protein in mpkCCD cells (1181.15)
Authors: Yip Kay‐Pong , Amin Jahanshah , Cha Byeong
Published: June 2021

AQP2 tagged with green fluorescent protein (GFP‐AQP2) has been used to monitor AQP2 trafficking in kidney cell lines. However, vectorial trafficking of GFP‐AQP2 resembling to that in the principle cells of collecting duct has not been demonstrated in real time in vitro. mEos2 is a photoconvertible fluorescence protein. To visualize AQP2 trafficking, chimeras with mEos2 fused to either the amino‐terminus of AQP2 (Eos‐AQP2) or the carboxyl‐terminus (AQP2‐Eos) via a 17 amino‐acids linker were constructed and expressed in mpkCCD cells on glass‐bottom dishes. Forskolin‐induced apical targeting of AQP2 in real time was monitored using video‐rate confocal microscopy at four dimensions (XYZ‐T). AQP2‐Eos chimeras expressed in mpkCCD cells were localized constitutively to the apical plasma membrane. In contrast, the Eos‐AQP2 chimeras trafficked from intracellular vesicles to the apical membrane in response to forskolin stimulation, indicating similar vectorial trafficking of AQP2 as in collecting duct. Co‐transfection of these two chimeras in 1:1 ratio increased the rate of AQP2 apical accumulation triggered by forskolin (~2‐fold). However, the synergic effect was abolished when the linker was reduced to 8 amino‐acids. These observations suggested that proximity of mEos at the amino‐terminus and the carboxyl‐terminus within the AQP2 tetramer modulates the response to cAMP stimulation.
High‐fat diet induced expansion of colon crypt epithelial proliferative zone towards lumen correlates with elevated innate inflammatory markers in the human‐relevant porcine model (123.2)
Authors: Vanamala Jairam , Radhakrishnan Sridhar , Eriksson Elisabeth , Charepalli Venkata , Kim Sung , Reddivari Lavanya
Published: June 2021

Recent evidence shows that high‐fat diet (HFD) alone causes colon cancer in mice; however, underlying mechanisms are not fully elucidated. An expansion of proliferative zone towards the crypt lumen is a biomarker for colon cancer in animal models and humans. We hypothesized that HFD induced expansion of colonic proliferative zone and elevation of proliferating index correlates with innate inflammatory markers in the porcine model that has similar gastrointestinal function/physiology as humans. Pigs (n = 8/group) were provided either standard diet (SD; 5% fat) or HFD (25% fat) for 13 wk. HFD elevated proliferative zone (Ki‐67; immunofluorescence; p = 0.02) and proliferative index (p = 0.06). HFD numerically increased (p = 0.15) distal colon expression of pattern recognition receptors TLRs 2/4 and TLR‐4 responsive genes NF‐κB, COX‐2 and TNF‐α (qPCR) compared to SD group. However, HFD elevated proliferative zone correlated with TLR‐4, NF‐κB, COX‐2 and TNF‐α expression (r = 0.77, 0.71, 0.78 and 0.62, respectively, p = 0.02). HFD group had greater distal colon macrophage infiltration (mac387; immunohistochemistry; p = 0.1) that correlated with TLR‐4 expression (r = 0.52, p = 0.05). As proliferating colonocytes are highly susceptible to damage due to oxidative stress/inflammation, expanded proliferative zone may partly explain how chronic HFD consumption causes colon cancer.

Grant Funding Source: Supported by USDA‐NIFA NRI Grant 2009‐55200‐05197
PINCH‐Rsu‐1 complex in regulating liver size and tumorigenesis (144.6)
Authors: Donthamsetty Shashi , Bhave Vishakha , Mars Wendy , Michalopoulos George
Published: June 2021

PINCH protein is part of the ternary complex known as the IPP (Integrin linked kinase(ILK)‐PINCH‐Parvinα) complex. PINCH itself binds to ILK and to another protein known as Rsu1 (Ras suppressor 1). We generated PINCH 1 and PINCH 2 Double knockout mice (referred as PINCH DKO mice). PINCH2 elimination was systemic whereas PINCH1 elimination was targeted to hepatocytes. The genetically modified mice were born normal. The mice were sacrificed at different ages after birth. Soon after birth, they developed abnormal hepatic histology characterized by disorderly hepatic plates, increased proliferation of hepatocytes and biliary cells and increased deposition of extracellular matrix. After a sustained and prolonged proliferation of all epithelial components, proliferation subsided and final liver weight by the end of 30 weeks in livers with PINCH DKO deficient hepatocytes was 40% larger than the control mice. The livers of the PINCH DKO mice were also very stiff due to increased ECM deposition throughout the liver, with no observed nodularity. Mice developed liver cancer by one year. These mice regenerated normally when subjected to 70% partial hepatectomy and did not show any termination defect. Ras suppressor 1 (Rsu‐1) protein, the binding partner of PINCH is frequently deleted in human liver cancers. Rsu‐1 expression is dramatically decreased in PINCH DKO mouse livers. Increased expression of Rsu‐1 suppressed hepatocyte proliferation and migration in HCC cell lines. These changes were brought about not by affecting activation of Ras (as its name suggests) but by suppression of Ras downstream signaling via RhoGTPase proteins. In conclusion, our studies suggest that removal of PINCH results in enlargement of liver and tumorigenesis. Decreased levels of Rsu‐1, a partner for PINCH and a protein often deleted in human liver cancer, may play an important role in the development of the observed phenotype..

Grant Funding Source: (5R01CA035373 and 5R01CA103958
Modulating myeloperoxidase‐induced endothelial damage by a carbon monoxide‐releasing molecule, CORM‐3 (146.9)
Authors: Patterson Eric , Capretta Alfredo , Fraser Douglas , Potter Richard , Cepinskas Gediminas
Published: June 2021

Previous work has demonstrated that carbon monoxide releasing molecules (CORMs) suppress inflammation, however, the mechanisms are not well understood. Neutrophil (PMN)‐derived myeloperoxidase (MPO) is known to play a significant role in the pathophysiology of numerous inflammatory disorders through: 1) direct peroxidation and 2) producing hypohalous acids, (e.g. hypochlorous acid). Thus, an overwhelming MPO‐dependent production of oxidants in the sub‐endothelial space after PMN degranulation, contributes to tissue damage and propagating inflammation.

We hypothesized that CORM‐3 interferes with MPO’s catalytic activity, and thereby mitigates endothelial inflammatory damage.

In vitro assays were used to study MPO catalytic activity inhibition. Further, live cell in vitro assays were used to investigate endothelial damage through measuring reactive oxygen species (ROS) and cellular permeability.

Our results indicate that CORM‐3 inhibits total MPO activity as well as MPO’s peroxidation and halogenation cycles. Cellular assays determined that ROS production and cellular permeability are decreased when extracellular MPO is treated with CORM‐3. In all assays inactivated CORM‐3 (iCORM‐3) was significantly less effective than CORM‐3.

We conclude that CORM‐3 may mitigate inflammatory damage partly through inhibiting MPO activity.

Grant Funding Source: Supported by Heart and Stroke Foundation, HSFO‐393 and LHRI IRF‐025‐09
Regulation of intestinal epithelial apoptosis by protease‐activated receptor 2 involves EGFR‐transactivation and is associated with Mcl‐1 upregualtion (151.1)
Authors: Iablokov Vadim , MacNaughton Wallace
Published: June 2021

Colonic biopsies from inflamed colon have higher levels of epithelial apoptosis than biopsies from healthy individuals. Therapies that inhibit intestinal epithelial apoptosis may decrease the inflammation observed in inflammatory bowel disease. We previously showed that signaling by PAR2, a GPCR activated by serine proteases, delayed IFN‐γ & TNF‐α‐induced apoptosis in colonic epithelial (HT‐29) cells. The observed decrease in the cleavage of caspase‐8, 9, 3 and PARP following the activation of PAR2 by 2‐furoyl‐LIGRLO (2fLI) was shown to be dependent on the activities of PI3K and ERK1/2. In this study we found that selective inhibition of EGFR with AG1478 blocked the phosphorylation of PI3K and ERK1/2. Pre‐treatment with AG1478 prior to the addition of IFN‐γ & TNF‐α also blocked 2fLI‐induced intestinal epithelial survival, as determined by PARP cleavage. Modulation of BCL‐2 family members was then investigated due to their known function in regulating mitochondrial permeability and apoptosis. Protein expression of pro‐apoptotic BAK, BAX and BIM were not altered by either cytokine or 2fLI treatment. Likewise, no change in expression of anti‐apoptotic BCL‐XL was observed. Treatment with 2fLI stimulated phosphorylation and inactivation of the apoptotic BH3‐only protein, BAD. Knockdown of BAD with siRNA, however, did not alter 2fLI‐stimulated intestinal survival. Finally, 2fLI stimulated a rapid increase in anti‐apoptotic MCL‐1 expression. PAR2 signaling reduces epithelial apoptosis in response to inflammatory cytokines via EGFR transactivation and possibly by regulation of MCL‐1 expression. Our findings may represent a mechanism whereby proteases facilitate epithelial cell survival and colonic healing after inflammation.

Grant Funding Source: Supported by the Crohn’s and Colitis Foundation of Canada
High MUC2 production in goblet cells causes increased susceptibility to ER stress and apoptosis (151.4)
Authors: Tawiah Adelaide , Moreau France , Chadee Kris
Published: June 2021

MUC2, a large glycoprotein produced by goblet cells in the colon, forms a protective mucus blanket over the epithelium as the first line of host defense. During pathological conditions such as inflammatory bowel diseases, there is accelerated biosynthesis and secretion of MUC2. Surprisingly, little information is known on how MUC2 production is regulated and whether goblet cells undergo increased stress in response to high MUC2 biosynthesis and secretion. In this study we investigated the role of MUC2 in goblet cell stress using a high mucin producing cell line, HT29‐H, and a clone of HT29‐H (HT29‐L) in which MUC2 has been silenced using lentivirus shRNA. Cells were treated with tunicamycin and MG132, and markers for endoplasmic reticulum (ER) stress and apoptosis were quantified. Compared to HT29‐L cells, HT29‐H cells exhibited a greater dose‐and time‐dependent increase in ER stress markers GRP78, ATF4, CHOP, sXBP1 and AGR2 in response to both tunicamycin and MG132. ER stress also caused a decrease in phosphorylation of Akt and increased apoptosis in HT29‐H cells 6h after treatment. Phospho‐Akt in HT29‐L cells was however sustained, decreasing slightly only after 24h with less apoptosis compared to HT29‐H cells. Our findings indicate that MUC2 induces goblet cell stress and apoptosis which could subsequently lead to diminished mucus barrier function.

Grant Funding Source: Supported by CIHR
The mini ultrasound institute: does incorporating ultrasound in the anatomy curriculum increase students’ understanding of living anatomy and comfort with new technology? (211.4)
Authors: Smither Fantley , Bhagra Anjali , Lachman Nirusha , Pawlina Wojciech
Published: June 2021

Despite increase in residency programs including ultrasound training, few medical schools have incorporated it into their curricula. The Gross Anatomy course at Mayo Medical School has introduced ultrasound in the curriculum. Cadaver dissection teaches students static anatomical relationships, but ultrasound offers dynamic display of how those relationships can change with movement. Ultrasound curriculum consists of four 1 hour didactic sessions and five 30 minute hands‐on modules, covering Carpal tunnel, Heart, Abdominal viscera, and Doppler imaging of blood flow. Each module is guided by a checklist of techniques and structures. Students are graded using ARS system, and ultrasound objectives are incorporated into the final exam.

This study aimed to assess effectiveness of ultrasound curriculum in a 7 week anatomy course. Students were asked to complete pre‐ and post‐ test surveys that assessed whether ultrasound sessions allowed them to better appreciate living anatomy, learn the basics of operating a portable ultrasound machine, and become more comfortable with medical technology. Pre and post surveys showed that ultrasound helped students appreciate living anatomy, and that they were comfortable with technology. There was an increase in students’ perception of their ability to interpret ultrasound images with a p‐value of 0.000026. Ultrasound was a successful addition to the anatomy curriculum.
Neuroanatomy education ő tools to make it active, clinical, and mobile (215.3)
Authors: Fisch Adam
Published: June 2021

This session will address best methods to incorporate active learning into traditional didactic teaching to improve student participation in neuroanatomy class. It will highlight online resources (web and app) that are actively engaging, clinically relevant, and mobile to help professors design a preparatory study program for their students that is self‐directed. By participating in this session, audience members will be taught the key features of active learning and will learn principles for evaluating online resources currently available in neuroanatomy.
Bbs1 gene is required for wound healing (216.5)
Authors: Guo Deng Fu , Starks Rachel , Sheffield Val , Rahmouni Kamal
Published: June 2021

Bardet‐Biedl syndrome (BBS) is a pleiotropic autosomal recessive disorder associated with several features including obesity, polydactyly, retinal degeneration, hypogenitalism, leaning difficulty and renal dysfunction. Mice bearing an M390R mutation in Bbs1 gene (which a common mutation in human BBS) recapitulates many BBS phenotypes including obesity and hypogenitalism. However, the role and contribution of Bbs1 gene to cell migration and tissue repair remains unclear. Using wound healing assays, we found that cultured mouse embryonic fibroblasts (MEFs) derived from Bbs1M390R knock‐in mice have severely compromised migratory ability compared to the MEF derived from wild type mice. Activation of AKT by platelet‐derived growth factor‐AA (PDGF‐AA) was also markedly reduced in Bbs1M390R MEF, suggesting that decreased PDGFRα signaling contributes to the migratory defects. Immunofluorescence microscopy analysis with acetylated α‐tubulin showed that both wt and BBS1‐Ki MEFs form primary cilia. The primary cilia were oriented towards the leading edge of the wound in wt MEFs. In marked contrast, primary cilia of BBs‐KI MEFs appeared randomly positioned and lacked an axis of orientation towards the edge of the wound. Furthermore, in vivo wound healing assays showed defects in Bbs1M390R knock‐in mouse compared to control littermates. These findings demonstrate that the Bbs1 gene is required for migration and tissue repairs.

Grant Funding Source: NIH and AHA
Drugs and the brain, the MOOC (221.2)
Authors: Lester Henry , Cohen Bruce
Published: June 2021

How does a MOOC differ in value and impact from previous “distance‐learning” technologies? (1) A major additional possibility is the online community that springs up around the course. “Drugs and the Brain” brought some people with real‐life interest in drug mechanisms, and others with detailed scientific experience. Quantifying the letter group: of the students who finished the 2012‐2013 course and earned “statements of accomplishment”, ~ 10% of the students had PHD degrees and 7% had MD degrees, and ~ 7% had professional degrees in pharmacy. This online community requires detailed curation, moderation, and judgment. For the 2013‐2014 rendition, we plan to have two undergraduate TA's as curators. (2) A secondary possibility is the concept of instantaneous feedback on exams and quizzes. This can also be incorporated in previous technologies.

What are limitations of the MOOC? (1) After all limitations in bandwidth and technology have been overcome, “internet time” will still be constrained by the fact that the world is round. The instructor will be asleep when some students want to communicate, and vice‐versa. (2) The course staff must invest formidable effort to optimize the learning experience. In this area, we include analyzing quiz responses, clicks, etc. We also include human evaluation of essays and other student responses. These are both wonderful problems, in the sense that we have too much data!
Chaperone discovery (226.2)
Authors: Bardwell James
Published: June 2021

We have devised a genetic selection that give bacteria the stark choice between death and stabilizing poorly folded proteins. The bacteria respond to this selection by enhancing the expression of a number of distinct proteins. The expression of these folding helper proteins enables the the bacteria to substantially increase the level of the unstable proteins and therefore live. When these helper proteins are purified they turn out to be effective in vitro as molecular chaperones, which help prevent the aggregation of proteins and aid in protein refolding. Optimizing protein folding in the cell has thus led to the uncovering of a number of previously uncharacterized chaperones.
Preparing for your career: lessons from my own professional journey (233.1)
Authors: Fuhrmann Cynthia
Published: June 2021

Interested in leadership, education, and teaching? There are ways to move into such roles without pursuing the traditional tenure track. Now Assistant Dean of Career & Professional Development at UMass Medical School, Dr. Fuhrmann will describe her journey from PhD in Biochemistry to educator and administrator in the Graduate Dean's office. Her career experiences have included development of grant‐funded educational programs, teaching, and peer‐reviewed educational research. She has been active at the national level, as co‐author of the AAAS/ScienceCareers website “myIDP” and a frequent presenter at conferences and universities. In the last part of her talk, Dr. Fuhrmann will share tips for how to prepare for a variety of scientific careers‐‐whether a path in academic research, academic administration, or research/non‐research careers beyond academe.
Science and law: emerging challenges (233.4)
Authors: Andrews Lori
Published: June 2021

As courts, legislatures, and other social institutions deal with the advisability of gene patents, the safety of nanotechnology, and the Constitutional implications of data aggregation, there is a growing role for scientists and engineers in the world of policy. This presentation will address the difference between the methodologies employed by lawyers and scientists and will highlight the emerging technologies whose regulation needs input from biologists and chemists.
The fission yeast Pfh1 DNA helicase promotes fork progression through multiple types of replication obstacles (236.1)
Authors: Zakian Virginia , Sabouri Nasim , Capra Tony , McDonald Karin , Cristea Ileana , Bochman Matthew
Published: June 2021

The fission yeast Pfh1, an essential 5’ to 3’ helicase, is a member of the highly conserved Pif1 family of DNA helicases. Mutation of human PIF1 (hPIF1) within the 21 amino acid Pif1 signature motif is associated with elevated cancer risk, suggesting that hPIF1 is a tumor suppressor gene. Like budding yeast Pif1 family helicases, S. pombe Pfh1 has a key role in DNA replication. By both mass spectrometry and in vivo experiments, Pfh1 is a replisome component. By chromatin immune‐precipitation plus deep sequencing, cells depleted of Pfh1 have increased fork pausing and DNA damage near many hard to replicate sites, as indicated by high DNA polymerase occupancy and phosphorylated histone H2A, respectively. These sites include highly transcribed genes, telomeres, and sequences able to form G‐quadruplex (G4) structures in vivo. Pfh1 suppresses G4‐induced gross chromosomal rearrangements in Pif1 helicase deficient budding yeast while Pfh1‐L430P, which has the mutation associated with human cancer, does not. These data suggest that in the absence of Pfh1, replication pausing and DNA damage results in genome instability of the sort associated with human tumors.
Selective autophagy in the cellular stress response (237.3)
Authors: Cuervo Ana Maria
Published: June 2021

Our group is interested on a selective form of inducible autophagy, known as chaperone‐mediated autophagy (CMA) and its connections with aging and disease.

Substrate proteins for CMA are delivered to the lysosomal lumen for degradation by directly crossing the lysosomal membrane. This process is mediated by a set of cytosolic and lysosomal chaperones and by a receptor protein at the lysosomal membrane, the lysosome‐associated membrane protein type 2A (LAMP‐2A). The limiting step of CMA is the binding of substrates to LAMP‐2A and levels and organization of LAMP‐2A at the lysosomal membrane underlie the molecular basis for the regulation of CMA. This pathway is active in most cell types in mammalians but its activity varies depending on cellular conditions. In recent years, to gain a better understanding of the physiological role of this pathway we have developed a transgenic mouse models with compromised CMA in different organs. These studies have provide unique insights on the consequences of CMA malfunctioning in the pathogenesis of detrimental human pathologies, such as cancer, neurodegenerative and metabolic diseases.

In this talk, I will describe some of the recent findings on the molecular effectors and regulators of CMA, on the physiological relevance of CMA and the contribution of its malfunctioning to disease.

This work is supported by grants from NIH/NIA and NIH/NIDDK
Burkinabe infants given small quantity lipid‐based nutrient supplements and illness treatment in infancy score higher in motor, language, and personal‐social development (251.1)
Authors: Prado Elizabeth , Abbeddou Souheila , Jimenez Elizabeth , Somé Jérôme , Ouédraogo Zinewendé , Vosti Stephen , Dewey Kathryn , Hess Sonja , Ouédraogo Jean‐Bosco , Brown Kenneth
Published: June 2021

Conception to age two years is a crucial period for brain growth and development of motor, cognitive, and socio‐emotional skills. Many children in developing countries fail to reach their developmental potential in these areas. Small‐quantity lipid‐based nutrient supplements (SQ‐LNS) during infancy may improve these aspects of development, which depend on adequate nutrition. Zinc is a key nutrient, which affects brain development through its role in DNA and RNA synthesis and macronutrient metabolism.

In a partially masked, placebo‐controlled, randomized trial, communities in rural Burkina Faso were assigned to intervention (IC) or non‐intervention communities (NIC). 2469 eligible IC children were randomly assigned to receive 20g LNS/day with varying amounts of zinc, and treatment of malaria and diarrhea from 9‐18 months of age. Children in NIC (n=797) did not receive any intervention during the same period. Motor, language, and personal‐social development was assessed at 18 months in a subgroup (n=747 IC; n=376 NIC).

Children in IC scored 0.33 SD higher in motor, 0.33 SD higher in language, and 0.30 SD higher in personal‐social development than children in NIC. Compared to NIC 52%, 45%, and 60% fewer children in IC were in the lowest decile of motor, language, and personal‐social scores, respectively. Children who received different amounts of zinc in LNS (0 or 10 mg) or a tablet (5 mg) did not differ significantly in 18‐month motor, language, or personal‐scores.

Providing SQ‐LNS daily with or without zinc along with malaria and diarrhea treatment significantly improved motor, language, and personal‐social development in young Burkinabe children.

Grant Funding Source: Bill & Melinda Gates Foundation
Socioeconomic influences moderate the relation between the size of food‐based activity spaces and body mass index (255.6)
Authors: Scully Jason , Moudon Anne , Hurvitz Phil , Cook Andrea , Aggarwal Anju , Drewnowski Adam
Published: June 2021

Objective: To investigate socioeconomic influences on the association between food‐based activity spaces and body mass index.

Background: Activity space (AS), comprising all the places that people visit in a given period of time, is one measure of exposure to the built environment. Decomposing AS by activity type allows researchers to examine agent‐environment interactions and their impacts on health. Food‐based activity space (FBAS), defined as the places where people purchase food, is a subset of AS.

Methods: The Seattle Obesity Study II used address‐based sampling and survey methods to recruit a population‐based longitudinal cohort of 516 male and female King County adults. All participants completed behavioral, dietary and health questionnaires, maintained travel logs for 7 days and were issued GPS tracking devices for 7 days. Both AS and FBAS were represented by convex hulls generated from GPS points corresponding to times in travel logs when subjects recorded food shopping or visiting a supermarket.

Results: AS was significantly linked to diverse socio‐demographic measures including education, income, employment, number of cars, commuting distance, and number of children in the household. A small correlation between average FBAS area and BMI (r=0.17, p<0.01) was found.

Conclusions: This relation may be moderated by socio‐demographic variables affecting AS. Lower FBAS may limit access to healthier foods by lower‐income participants, whereas higher income participants have greater AS areas and therefore may have more options.

Grant Funding Source: NIH grant R01 DK076608‐06
Antenatal care and counseling measures increase iron and folic acid receipt among pregnant women in Bihar, India (256.3)
Authors: Wendt Amanda , Young Melissa , Stephenson Robert , Webb Girard Amy , Ramakrishnan Usha , Martorell Reynaldo
Published: June 2021

In Bihar, India maternal anemia is a public health problem. Using District Level Household Survey data (2007‐08), we used logistic regression to examine associations between ANC practice and counseling, and any IFA receipt, adjusting for covariates. We created two 3‐level variables to describe ANC quality using 9‐point scales assigning credit to activities that are part of routine ANC practice (e.g. measuring weight, height, blood pressure) and counseling (e.g. advice on nutrition, breastfeeding, cleanliness). The women (n=12,515) were 15‐49 years old (mean: 25.5 years), 38% received any IFA, 9% consumed any IFA for 90+ days, 22% received 5‐9 ANC practices, and 22% received 5‐9 ANC counseling topics.

We found women reporting 5‐9 and 1‐4 ANC practices completed vs. none (AOR: 4.4, 95% CI: (3.8, 5.0); AOR: 2.7; 95% CI: (2.5, 3.0), respectively) were more likely to receive any IFA during their last pregnancy. The adjusted models also revealed that women who reported 5‐9 and 1‐4 vs. no ANC counseling topics addressed (AOR: 2.2, 95% CI: (1.9, 2.5); AOR: 1.7, 95% CI: (1.6, 1.9), respectively) were also more likely to receive IFA. Education, wealth index, and number of ANC visits were also positively associated (p<0.05) with IFA receipt. Our findings indicate that ANC quality measures are significantly associated with prenatal IFA receipt even after controlling for number of ANC visits and socio‐demographic characteristics.

Grant Funding Source: Funding support provided by a BMGF grant through a subcontract with CARE‐India
Qualitative evaluation of interactive features in HOT (Healthy Outcomes for Teens) Project website (262.4)
Authors: Muzaffar Henna , Chapman‐Novakofski Karen , Castelli Darla
Published: June 2021

The objective was to identify the adolescents’ perceived usefulness of incorporating different interactive features; and also to assess any gender differences for preference of interactive features on the intervention website. An iterative process developed the questions focused on internet use, ease of using the intervention site, general content/language, preference for interactive features and reading. Nine focus groups (19 boys, 18 girls) were conducted and the data was analyzed using content analysis, inductive development, and negative case analysis. Majority (81%) thought website was easy to use (wording, information and navigation); 19% thought some words were complex. Preference of the interactive features was videos (68%), games (62%), pictures (41%) and voiceovers (20%). Majority (70%) thought nothing was distracting. Four themes emerged: 1) ‘preference for computer over classical classroom’ with subcategories familiarity, fun, and learn at your own pace; 2) ‘reinforcements’; 3) ‘distractions’; 4) ‘gender evaluations’. Conclusion: Internet based interventions were perceived more favorably by the adolescent population than traditional classroom instruction. The majority of the interactive features were perceived as reinforcements except Google maps and seeing rating of friends. Future work should evaluate concepts learned more fully when interactive features included.

Grant Funding Source: Funding: American Dietetic Association, National Soybean Laboratory, University of Illinois Extensio
Novel alkylresorcinol metabolites in human urine as potential exposure biomarkers for whole grain wheat and rye intake (270.6)
Authors: Sang Shengmin , Zhu Yingdong , Shurlknight Kelly
Published: June 2021

Biomarkers of dietary intake are prominent tools in nutritional research. Alkylresorcinol (AR) metabolites, 3,5‐dihydroxybenzoic acid (3,5‐DHBA) and 3‐(3,5‐dihydroxyphenyl)propanoic acid (3,5‐DHPPA), have been proposed as exposure biomarkers of whole grain (WG) wheat and rye intake. However, the profile of AR metabolites is not fully understood. The aim of this study was to investigate the metabolism of ARs in mice and in humans, while further determining urinary pharmacokinetics of the novel AR metabolites to explore their potential as biomarkers of WG wheat intake. Utilization of LC‐MS approach resulted in ten AR metabolites (1‐10) identified in mice and in humans, including three phenolic acids and seven of their phase II conjugates. Among them, two novel metabolites were discovered, 5‐(3,5‐dihydroxyphenyl)pentanoic acid (3,5‐DHPPTA) and 2‐(3,5‐dihydroxybenzamido)acetic acid (3,5‐DHBA glycine). The structures of these two metabolites were confirmed by comparing with authentic standards synthesized in house. In the pharmacokinetic study, a group of twelve volunteers followed a polyphenolic restricted diet for 4 d before ingesting WG wheat bread containing 61mg ARs. Urine samples were collected for 32 h, and AR metabolites were quantified with HPLC‐CEAD. The mean urinary excretion rates and mean t1/2 of 3,5‐DHPPTA, 3,5‐DHBA glycine, 3,5‐DHBA and 3,5‐DHPPA at each time point were determined. Our results suggest that 3,5‐DHPPTA and 3,5‐DHBA glycine may be utilized in combination with 3,5‐DHBA and 3,5‐DHPPA as potential biomarkers to increase the accuracy of recording WG wheat and rye intake in epidemiologic studies. Further validation of 3,5‐DHPPTA and 3,5‐DHBA glycine as potential biomarkers is warranted.

Grant Funding Source: 1This work was partially supported by funding from USDA‐NIFA grant 2012‐38821‐20012 to S. Sang.
Computing on the anatomical form for disease discovery (338.1)
Authors: Haendel Melissa , Mungall Chris
Published: June 2021

Elucidating evolutionary processes, disease, and developmental dysfunction requires understanding variation in phenotype. However, anatomical information, integration, and retrieval are key challenges as reference to anatomy is largely unstructured or encoded in a variety of formats. An ontology is useful to annotate, link, and retrieve anatomical data, and can be computed on using a reasoner. The use of anatomy ontologies provides a new mechanism on which to base a systems biology approach to understanding phenotypic diversity and dysmorphology. Here, we present our efforts as part of the Monarch Initiative to support the identification of relevant genes linked to human diseases. Towards this end, we constructed the Uberon multi‐species anatomy ontology to provide generalization and links between anatomical structures in model organisms. Use of Uberon with other modular ontologies, such as the Biological Spatial Ontology (BSPO) to record spatial and topological relationships among biological structures, and the Phenotype and Trait Ontology (PATO), enables standardized representation of variation in morphological form. These ontologies act not only as data standards, but provide the connection of anatomical form to gene expression data, atlases, and phenotypic outcomes ‐ thereby enabling deep anatomical analysis to persevere, grow, and shed new light on how biological systems function.
30 years in 30 minutes: integrating imaging, cell and developmental biology with teaching and service (341.1)
Authors: Svoboda Kathy
Published: June 2021

The American Association of Anatomists (AAA) has been integral in my education and academic career. I was trained as a developmental biologist and anatomist at the University of Nebraska Medical Center. Dr. K Sue O’Shea was my mentor and Dr. William K. Metcalf was my departmental chair. As students we were expected to be competent in teaching all anatomy disciplines. My introduction to the AAA was the Omaha, NE annual meeting in 1980. I also met my postdoctoral advisor, Dr. Elizabeth Hay at the Indianapolis meeting (1982) and interviewed with Dr. Allen Peters for my first professorship at the Reno meeting (1986). I’ve taught medical and dental students Gross Anatomy, Histology and Human Development at Harvard, Boston University School of Medicine and Baylor College of Dentistry. In parallel, my research used morphological (TEM, SEM and LM), biochemical and molecular biology approaches to investigate signal transduction pathways controlling developmental processes and cell biology of adult tissues. The AAA has been my home society since my graduate student days in the 80’s through my current senior faculty career. In this talk I will illustrate how the AAA was the glue that held my career together with good friends, great science and networking.
Solving large and difficult structures with less experimental data (346.1)
Authors: Levitt Michael
Published: June 2021

Complexes of protein and nucleic acid molecules are the major machines of living cells. Solving their structures is hard so we generate millions of models that are examined against data from cross‐linking mass spectrometry, cryo‐electron microscopy and X‐ray crystallography.

Our methods are developed on Eukaryotic group II Chaperonin CCT, a 0.95 megaDalton (mD) complex. In eukaryotes, 8 different genes encode the subunits of this ATP‐powered nanomachine; sequence similarity made the 40,320 (8 factorial) possible arrangements indistinguishable in previous cryo‐electron microscopy and crystallographic analysis.

We used cross‐linking, mass spectrometry (XL‐MS) and combinatorial homology modeling. After using mass spectrometry to identify 63 cross‐linked pairs, we construct all 40,320 homology models of the TRiC particle. By comparing each model with the cross‐link set, we discovered that one model is significantly more compatible than any other model.

Next, we re‐examine the 3.8 Å resolution X‐ray data of yeast CCT. Our method of R‐Value Exploration tests all 2,580,460 possible models. This unbiased analysis singles out with overwhelming significance one model. This models refines to a lower R‐free than other models Our structure reveals details of the unique conformation of each subunit, and suggests a mechanism of action.

For a new system, we combine our methods with cryo‐EM to determine the arrangement of subunits of a complete, 1.5 mD, 32‐protein, RNA polymerase II (pol II) transcription pre‐initiation complex (PIC). Promoter DNA associates with the general transcription factors (GTFs) suspended above the pol II active center cleft. DNA‐pol II interaction occurs only after promoter melting.
Keeping mitochondria and ER together: a matter of life, death and neurodegeneration (349.2)
Authors: Scorrano Luca
Published: June 2021

Mitochondrial ultrastructural and morphological changes have been implied in the control of several physiological and pathological changes, including apoptosis. However, the role of mitochondrial dynamics in the control of complex cellular cues and in response to reversible and irreversible cellular damage is not clarified. Today we will overview the key experiments that shed light on the role of mitochondrial shape and ultrastructure in cell physiology and we will present our recent data obtained in genetic models of ablation and up‐regulation of the key mitochondrial shaping proteins Optic atrophy 1 (Opa1) and mitofusin in the mouse and in embryonic stem cells. The in vivo experiments of tissue damage by inducing atrophy, apoptosis or ischemia/reperfusion indicate that the master cristae biogenetic regulator Opa1 can prevent multiple forms of tissue damage by controlling mitochondrial cytochrome c release and metabolic efficiency. Ablation of Mitofusin 1 and 2 in the embryonic mouse heart, or gene‐trapping of Mitofusin 2 or Opa1 in mouse embryonic stem cells (ESCs), arrested mouse heart development and impaired differentiation of ESCs into cardiomyocytes. Gene expression profiling revealed roles for TGFβ/BMP, SRF, GATA4, and Mef2 differentiation factors, linked to increased Notch1 activity that, unexpectedly downstream of the Ca2+‐dependent phosphatase calcineurin, impaired ESC differentiation. Orchestration of cardiomyocyte differentiation by mitochondrial morphology reveals how mitochondria, Ca2+ and calcineurin interact to regulate Notch1 signaling. Thus, mitochondrial shape and ultrastructure dictate organelle function and complex tissue responses.
Breaking asymmetry: phospholipid scrambling by GPCRs and TMEM16 proteins (351.2)
Authors: Menon Anant
Published: June 2021

Polar lipids must flip rapidly, and often bidirectionally, across membranes to support cellular life. For example, phospholipids are synthesized on the cytoplasmic face of the endoplasmic reticulum (ER) and must be apportioned between the luminal and cytoplasmic leaflets for uniform expansion of the ER during cell growth. Transbilayer movement of lipids is also needed for the generation, maintenance and dissipation of transbilayer lipid asymmetry at the plasma membrane. As flipping is energetically costly, specialized transporters increase its intrinsically low rate to a physiologically relevant level. While some of these transporters couple ATP hydrolysis to lipid movement, many function without any discernible metabolic energy input. The molecular identification of these latter ‘ATP‐independent flippases’, also termed ‘scramblases’, has eluded researchers for decades. We now report the first examples of this novel class of proteins: rhodopsin, a prototypical G protein‐coupled receptor, is a constitutively active, ATP‐independent phospholipid flippase (Menon et al. (2011) Curr. Biol. 21: 149), and afTMEM16, a fungal homolog of the TMEM16 family of ion channels is a Ca2+‐dependent phospholipid scramblase (Malvezzi et al. (2013) Nature Commun. 4: 2367). Both proteins break transbilayer lipid asymmetry.
Making connections: control of PI kinase signaling at ER‐PM junctions (351.3)
Authors: Manford Andrew , Emr Scott , Stefan Christopher
Published: June 2021

Information transfer between intracellular organelles must take place to regulate the size, shape, composition, and function of individual organelles, as well as for normal cell growth and development. The endoplasmic reticulum (ER) forms an expansive membrane network that contacts and participates in crosstalk with several other organelles in the cell, most notably the plasma membrane (PM). ER‐PM junctions have well‐established functions in the movement of signaling molecules, such as lipids and ions, between the ER and PM. However, little is known about the architecture and structural components of ER‐PM junctions. Using a quantitative proteomics approach, we have identified three families of ER‐PM tether proteins in yeast: the VAP proteins Scs2/22, Ist2 (related to the TMEM16 channel family), and the tricalbin proteins Tcb1/2/3 (orthologs of the extended synaptotagmin‐like proteins E‐Syt1/2/3). Loss of the ER tether proteins results in separation of the peripheral ER network from the PM and the accumulation of an ER meshwork in the cytoplasm. The collapse of the cortical ER network leads to ER stress, activation of cellular stress response pathways, and mis‐regulation of phosphoinositide (PI) lipid signaling at the PM. Thus, ER‐PM junctions have critical roles in maintaining the structure and function of the ER, as well as plasma membrane homeostasis. Our results provide a molecular mechanism for ER‐PM contact site formation and fundamental insights into the function of these organelle junctions in the control of PI kinase signaling networks and cellular stress response pathways.
Repair pathway crosstalk in genome stability maintenance through BRCA1/2‐mediated homologous recombination (352.1)
Authors: Cooper Priscilla , Trego Kelly , Groesser Torsten , Parplys Ann , Cmielova Jana , Wiese Claudia , Sung Patrick , Campisi Judith
Published: June 2021

XPG is an endonuclease required for nucleotide excision repair with important non‐enzymatic roles in base excision repair (BER) and transcription‐coupled repair (TCR). XPG enzymatic defects cause cancer‐prone xeroderma pigmentosum (XP), while truncating mutations cause the progeroid disorder Cockayne syndrome (CS). We now reveal an unexpected XPG role in homologous recombination (HR). XPG loss elevates the DNA damage response and causes double‐strand break (DSB) formation with pronounced genomic instability. XPG knockdown (KD) cells have impaired recovery from replicative stress, and DNA fiber analysis reveals inability to restart stalled replication forks. XPG interacts directly with the HR proteins RAD51, BRCA2, and PALB2 in a stable complex, and XPG KD results in their reduced chromatin loading and in decreased HR at site‐specific DSBs. Placing its role in HR upstream of BRCA2, XPG KD also reduces single‐strand annealing and increases chromatin‐bound BRCA1 and BRCA1 foci. Thus, loss of XPG function impairs replication fork maintenance by HR and may be important in BRCA‐associated cancers. It also accelerates aging, leading to cellular senescence or apoptosis and to severe progeria in XP‐G/CS patients and a mouse model. Whether this accelerated aging is related to XPG roles in TCR, BER, or HR remains to be determined.