bluuebunny/crossref_metadata_2025 huggingface dataset:
Hepatic glycolytic capacity decreases in mice with a FoxO1 overexpression in skeletal muscle
Authors: Lee Abraham D. , Al‐sorghali Aaron M. , Woods Carrie E. , Rampulla Anthony J. , McLoughlin Thomas J.
Published: June 2021

The purpose of this study was to test a hypothesis that the overexpression of FoxO1 in skeletal muscle induces an alteration in the activities of key hepatic enzymes involved in glucose metabolism. Liver samples and gastrocnemius muscles obtained from 7 control mice and 6 mice with an overexpression of FoxO1 in skeletal muscle were analyzed for the activities of phosphoenolpyruvate carboxykinase, fructose‐1, 6‐diphosphatase, glucose‐6‐phosphatase, phosphofructokinase (PFK), pyruvate kinase (PK), and citrate synthase (CS) in the liver and hexokinase, PFK, and CS in the muscle. The enzyme activities were determined from homogenized samples incubated in the presence of appropriate substrates by measuring products enzymatically or radioactively. The data were analyzed to determine differences between the two groups using Student's t‐test at a α level of P≤0.05. There were significant reductions in the activities of two hepatic glycolytic enzymes, PFK by 43% (P≤0.05) and PK by 21% (P≤0.05) in FoxO1 group in comparison with those of the control group. No significant difference was found between the two groups in the activities of the remaining enzymes. It is concluded that the overexpression of FoxO1 in skeletal muscles causes a decrease in hepatic glycolytic capacity via a cross‐talk between the two insulin‐target organs. Supported by Ohio Challenge Fund.
L‐and T‐type Ca2+ Channels in Human Cerebral Circulation
Authors: Harraz Osama F. , Starreveld Yves , Watson Tim , Menon Bijoy K. , Welsh Donald G.
Published: June 2021

L‐and T‐type Ca2+ channel expression is well documented in rat cerebral arteries. These channels play key but distinctive roles in setting cytosolic Ca2+, arterial tone and tissue perfusion. In this study, we examined the properties of Ca2+ channels in human cerebral arteries collected from resection surgeries. RT‐PCR analysis revealed, similar to rat and mouse, CaV1.2 (L) and CaV3.1/CaV3.2 (T) channel expression in human cerebral arteries. A whole‐cell Ba2+ current was isolated in cerebral arterial smooth muscle cells, divisible into nifedipine‐sensitive and‐insensitive elements. The nifedipine‐sensitive L‐type conductance displayed slower activation/inactivation at depolarized potentials. In contrast, the nifedipine‐insensitive component: 1) displayed sensitivity to T‐type blockers (NNC 55–0396); and 2) exhibited voltage/kinetic properties reminiscent to T‐type Ca2+ channels. The T‐type conductances (i.e. CaV3.1/CaV3.2) were separated by exploiting their differential Ni2+ sensitivity. A cross‐species comparison revealed that the voltage/kinetic properties of human T‐type channels were similar to rodent (rat, mouse) except for a rightward shift in the activation voltage‐dependence. This study is the first to document the presence of three distinct subtypes of Ca2+ channels in human cerebral circulation and future work will address their specific roles in the regulation of blood flow.
Brain astrocyte‐derived EETs and 20‐EHTE elicit opposing actions on calcium movement and KCa channel current activities in astrocytes
Authors: Gebremedhin Debebe , Zhang David X , Harder David R.
Published: June 2021

Cultured brain astrocytes incubated with arachidonic acid (AA) produce four CYP epoxygenase metabolites epoxyeicosatrienoic acids (EETs) 5,6‐, 8,9‐, 1,12‐and 14,15‐EET. The formation and action of 20‐hydroxyeicosatrienoic acid (20‐HETE) in brain astrocytes is not known. We investigated the capacity of brain astrocytes to express CYP‐4A‐ù‐hydroxylase protein and to convert AA to 20‐HETE. We also investigated the effects of 20‐HETE on membrane potential, KCa single‐channel activity, and on intracellular Ca2+ ([Ca2+]i) levels in cultured astrocytes. We found that astrocytes express CYP‐4A‐ù‐hydroxylase at the transcript and protein levels and produce 20‐HETE when incubated with AA. Treatment of astrocytes with 20‐HETE (100 nM) inhibited the openings of KCa single‐channel currents in cell‐attached patches and caused astrocyte membrane potential depolarization, whereas it had no effect on [Ca2+]i levels in astrocytes loaded with the Ca2+ probe Fura‐2AM. In contrast, treatment of cultured astrocytes with one of the EETs, 11.12‐EET increased [Ca2+]i level and activated astrocyte KCa channel currents. These findings indicate that the EETs and 20‐HETE produced and released by astrocytes could have opposing physiological actions at astrocyte end feet, which might be crucial for the maintenance of constant hyperemic cerebral blood flow during increased neuronal activation.
Interstitial Fluid Balance Resulting from Intestinal‐Hepatic Interaction
Authors: Rawle Natalie C. , Rosales Abigail , Galownia Tyler O. , Dongaonkar Ranjeet M. , Quick Christopher M.
Published: June 2021

The anatomical interconnections between the liver and intestines make interstitial fluid balance complex and experimental data exceedingly difficult to interpret. The portal vein connects the intestinal and hepatic blood circulations, and the cisterna chyli connects the intestinal and hepatic lymphatic systems. Furthermore, mathematical models designed to relate interstitial volumes and lymph flows to critical parameters either oversimplify the lymphatic system or overcomplicate the vascular system. Therefore, we developed a model that predicts interstitial pressures and lymph flows by adjusting the relative complexity of the lymphatic and vascular circulations. First, microvascular filtration was characterized by the Starling‐Landis equation. Second, lymphatic flow was made more realistic by assuming it to be more sensitive to inlet than outlet pressure. Third, blood flows were characterized by arterial, venous, and portal resistances. Finally, linearization and judicious use of simplifying assumptions yielded simple, algebraic solutions for interstitial pressures and lymph flows. The resulting model is comprehensive enough to reproduce conditions as diverse as interstitial edema, ascites formation, and changes in lymph flow, resulting from as diverse stimuli as inflammation, portal hypertension, hemodilution, and elevated central venous pressure.
Intracellular Cl‐concentration is increased in pulmonary arterial myocytes associated with chronic hypoxic pulmonary hypertension
Authors: Sun Hui , Sham James SK
Published: June 2021

Intracellular Cl− plays an important role in the regulation of contraction and proliferation of vascular smooth muscle. Yet little is known about the intracellular Cl− concentration ([Cl−]i) in pulmonary arterial smooth muscle cells (PASMCs), and whether it is altered in disease states such as chronic hypoxic pulmonary hypertension (CHPH) remains unknown. The present study was undertaken to address these issues. CHPH was induced by exposing rats to 10% O2 for 3 weeks. Gramicidin‐perforated patch clamp technique was used to measure the reversal potential (Erev) of caffeine‐induced Ca2+‐activated Cl− current (ICl Ca) in PASMCs with intact intracellular Cl−, and the [Cl−]i was calculated using Nernst equation. Caffeine‐induced currents and niflumic acid‐sensitive caffeine‐induced currents elicited by voltage ramps from −70 to +70 mV reversed at closely similar voltages in the same cell, suggesting that the caffeine‐induced current is mainly ICl Ca. The Erev of ICl Ca measured in hypoxic cells was more positive than that obtained from normoxic cells (−23.7±0.8, n=36 vs. −29.1±0.9 mV, n=33, p<0.001), giving rise to a higher [Cl−]i in hypoxic cells compared to controls (59.7±1.9 vs. 48.2±1.7 mM, p<0.001). Our results confirm that the [Cl−]i in PASMCs is well above equilibrium with resting potential, and reveal for the first time that the [Cl−]i is altered in PASMCs associated with CHPH. (Supported by NIH and AHA)
Ultra‐endurance exercise differentially affects highly unsaturated fatty acid composition in cheek cells and serum phospholipids
Authors: Volk Brittanie M , Kunces Laura J , Kupchak Brian R , Hoffman Martin D , Phinney Stephen D , Volek Jeff S
Published: June 2021

The Western States Endurance Run is a 100‐mile trail footrace through the Sierra Nevada Mountains. We hypothesized that the event would generate enough reactive oxygen species (ROS) in runners to cause ‘membrane damage’ as evidenced by degradation of highly unsaturated fatty acids, primarily arachidonate (AA) and docosahexaenoate (DHA). Ten runners (7M/3F, aged 27 to 60 yr) with a completion time of 22.83±4.26 hours provided buccal (cheek) cell and serum phospholipid (PL) samples for determination of fatty acid composition at baseline, immediately post‐race, and days 1 and 2 post‐race. Consistent with our hypothesis, cheek cell AA decreased by 19% (P = 0.003) and DHA by 23% (P = 0.002) immediately post‐race. In contrast, serum PL AA increased by 15% (P = 0.005) and DHA increased by 8% (NS). The implications of a decrease in cheek cell AA and DHA remain unclear, but they could reflect a failure of cellular antioxidant defenses to manage the cumulative ROS burden associated with ultra‐endurance exercise. The increase in serum PL AA may reflect release from other pools such as adipose tissue or damaged skeletal muscle, or alternatively it could represent an attempt to deliver AA to aid in repair and regeneration of ROS‐mediated tissue damage. The speed of fatty acid changes suggest that cheek cells can be used to assess acute systemic oxidative stress.
Putative small conductance Ca2+‐sensitive K+ channels isoforms and splice variants in mitochondria of guinea pig cardiac ventricular myocytes
Authors: Yang Meiying , Camara Amadou K.S. , Bienengraeber Martin , Kwok Wai‐Meng , Stowe David F.
Published: June 2021

Small Ca2+‐sensitive K+ channels (SKCa) exist in many cell types including cardiac atrial and ventricular. There are 3 isoforms of SKCa, i.e. SKCa 1, 2, and 3. Activation of SKCa channels may protect against ischemia (I) and reperfusion (R) injury. Recently we found SKCa channels exist in the inner mitochondrial membrane (IMM) of guinea pig cardiac ventricular myocytes and that SKCa channel opening protects against cardiac IR injury. It is unknown which SKCa isoforms and splice variants are specific for cardiac cell IMM so we searched for the gene products that might confer their distinct structural and functional characteristics. SKCa is expressed in cardiac ventricular cells, so ventricular tissue devoid of endovascular cells were used to extract total RNA, which was then reverse transcribed to cDNA. The resulting cDNA was amplified with SKCa 1, 2 and 3 gene‐specific primers. Results showed that both SKCa 2 and 3 were amplified, which suggests both isoforms may be expressed in ventricular mitochondria. Gene and amino acid sequence alignments showed the amplified SKCa 3 to be SKCa 3.1, which lacks residues 478–499, present in SKCa 3.2. Similar to rat SKCa 3.1, guinea pig SKCa 3.1 displayed a conserved COOH‐terminal but did not have a poly‐Glu repeat region. Our results indicate that in ventricular cell IMM there may exist two SKCa isoforms and at least one SKCa 3 splice variant that can be functionally characterized. (NIH, VA)
Decreased nitration of mitochondrial complex I by ROS/RNS scavenging during cardiac ischemia reperfusion injury
Authors: Cheng Qunli , Yang Meiying , Heisner James S , Bienengraeber Martin , Kwok Wai‐Meng , Camara A KS , Stowe David F
Published: June 2021

Protein nitration is a deleterious post‐translational modification mediated by peroxynitrite during cardiac ischemia reperfusion (I+R) injury. Nitration of mitochondrial complex I (CI) proteins could directly impair mitochondrial function and cardiac recovery. We tested this in 4 groups of guinea pig isolated hearts: time control (TC), I 25 min + R 20 min (IR), IR + 32°C hypothermia only during R (IRH), and IRH + a ROS/RNS scavenging cocktail (IRHS), i.e. MnTBAP, catalase, glutathione, and resveratrol, given only during R. Mitochondria were isolated from hearts at 20 min R, and CI proteins were enriched by sucrose gradient centrifugation. Identity was verified by Western blot with anti‐CI subunit antibodies of NDUFS1/NDUFS9 and purity by Commassie Blue staining on a native gel. Anti‐3‐nitrotyrosine AB was used to detect nitrated CI bands normalized to % density of NDUFS1 in the same blot after stripping. Relative nitration at different kDa's was expressed as % density of TC. Compared to TC (100%), nitrated band density was increased after IR (75 kDa = 156%; 30 kDa = 127%; 25 kDa = 123%; 18 kDa = 128%) and decreased after IRH for 75 kDa (118%) and 25 kDa (102%), and after IRHS for 18 kDa (100%). Orbitrap MS analysis of 30 and 18 kDa bands cut from BB stained gels identified several CI subunits as potential proteins for reduced nitration after IRHS. Residues less nitrated after treatment are potential sites to target for protection.
The feasibility of increased utilization of pulse crops in school meal service
Authors: Rueda Janice M.W.
Published: June 2021

As of 2012, schools participating in the National School Lunch Program (NSLP) are required to offer legumes, specifically pulse crops, which include dry beans, dry peas, lentils and chickpeas, as a vegetable at least once per week. The purpose of this research was to gain a better understanding of the ways pulse crops are being used in school food service. Surveys were administered and focus groups were conducted with food service employees (n=141) from ten different school districts in Washington. Qualitative and quantitative analyses were conducted. Pulse crops were most frequently reported served as hummus, black bean salsa or directly from the can as part of the salad bar. Lack of labor to prepare and lack of staff training were the most frequently cited challenges to utilizing pulse crops in school meals. Most frequently reported barriers to service of pulse crops include lack of preparation knowledge, lack of suitable recipes and lack of demand from students. These results indicate increasing pulse crops in school meals will require a collaborative approach that includes education of food service personnel and consumers and increased availability of ready‐made foods.
Sexual dimorphic regulation of NCC involves higher SPAK and NCC phosphorylation in female rodents
Authors: Rojas‐Vega Lorena , Castañeda‐Bueno Maria , Cervantes‐Perez Luz Graciela , Reyes‐Castro Luis , Hernandez Hector Damian , Zambrano Elena , Gamba Gerardo
Published: June 2021

It is known that NCC expression/function is subject to sexual dimorphic regulation and that estradiol administration enhances NCC expression in the distal convoluted tubule apical membrane of ovariectomized rats. To begging to elucidate the mechanisms involved, we analyzed the NCC activity, as well as the NCC and phospho‐T58 NCC expression in total and membrane fraction proteins, and total SPAK and phospho‐S383‐SPAK in total proteins, using specific antibodies, in proteins extracted from kidneys of wild type mice and normal or gonadectomized male and female rats, four weeks after sham or gonadectomy. Serum radioimmunoanalysis at four weeks confirmed the absence of sex hormones. In normal rats, the urinary response to bendroflumethiazide was higher in female than in male rats. No difference was observed in total or membrane NCC expression. However, phospho‐T58‐NCC was significantly higher in female than in male rats. This was associated with increased expression and S383 phosphorylation of SPAK in female than in male rats. Interestingly, the differences were eliminated by ovariectomy. No effect of orquiectomy on NCC and SPAK expression/phosphorylation was observed. In mice we observed that both, total and phospho‐T58‐NCC expression were significantly higher in female than in male animals. We conclude that increased activity of NCC in female rats is due to increased phosphorylation of NCC.
Molecular insights into mild exercise‐induced enhancement of spatial memory and neurogenesis: A DNA microarray approach
Authors: Inoue Koshiro , Okamoto Masahiro , Lee Min Chul , Matsui Takashi , Rakwal Randeep , Soya Hideaki
Published: June 2021

Many studies have reported on beneficial aspects of running to improve hippocampus‐related spatial memory and promote neuroplastic changes like adult hippocampal neurogenesis (AHN). Such research has also revealed molecular factors associated with molecular signaling by BDNF and IGF‐I leading to CREB activation. However, the optimum exercise intensity for genomewide beneficial effects remains unclear. We performed integrated analyses of behavioral (Morris Water Maze) and AHN data in conjunction with whole‐genome DNA microarray‐based transcript profiling in the rat hippocampus after 6 wks of exercise. Lactate threshold (LT) defined exercise intensity: moderate (ME, ;LT). Results show that ME, not IE, improved spatial memory and enhanced AHN compared to sedentary controls. Transcript profiling did not reveal the postulated regulators (BDNF, IGF‐I) relevant to exercise‐induced hippocampal neuroplastic change. We identified 604 ME‐influenced genes principally associated with lipid metabolism, compared to 415 IE‐influenced genes linked to disease and inflammatory function. This indicates that the less intense the exercise, the greater the development of hippocampal neuronal plasticity, and is likely associated with the expression of novel molecular components such as genes related to lipid‐metabolism rather than the previously characterized and well known factor BDNF.
How Stiff Is It? Characterizing the micro‐scale elastic modulus of hydrogels for use in regenerative medicine
Authors: Markert Chad D. , Guo Xinyi , Skardal Aleksander , Bharadwaj Shantaram , Zhang Yuanyuan , Bonin Keith , Guthold Martin
Published: June 2021

Previous research has indicated that the material properties of the cellular microenvironment modulate the developmental fate of stem cells: stem cells grown on soft surfaces tended to adopt a neuronal fate, while cells grown on hard surfaces tended towards an osteoblast phenotype. Our objective was to characterize the elasticity of hydrogel formulations intended to mimic physical properties that cells and tissues experience in vivo. We approached this objective with atomic force microscopy (AFM) indentation experiments, using a 5.3 micron sphere attached to the probe. We tested a variety of concentrations in a variety of biomaterials, including agarose, alginate, the collagens, fibrin, hyaluronic acid, keratin, Matrigel, and polyethylene glycol diacrylate (PEGDA). Manipulations of the concentration of biomaterials were detectable in AFM measurements as a function of elasticity E, and E tended to increase with increased concentration. Depending on the biomaterials chosen, and their concentrations, generation of tunable biocompatible hydrogels in the physiologic range is possible.
Melatonin promotes fracture healing at pharmacological doses on the early phase in perforating fracture model
Authors: Kim Koo , Lee Seunghoon , Hong Yunkyung , Lee Minkyung , Hong Yonggeun
Published: June 2021

Fracture has considerably improved through development of therapeutic approaches, although there showed which delayed recovery, nonunion, and complications after fracture injuries. Numerous studies reported that melatonin has a positive effect for bone formation in vitro. The aim of this study was to determine whether melatonin has an effect on fracture healing in femur perforating fracture model. SD rats (8‐week old) were randomly divided into fracture (Con), fracture+5 mg/kg melatonin treatment (LMT), and fracture+10 mg/kg melatonin treatment (HMT). After perforating fracture using micro drill, the rats were treated twice daily with melatonin at 7:00 and 19:00 during 21 days. Comparison of Con, LMT is significantly augmented the bone formation related gene expression, such as RUNX2, ALP, COL1, and DMP1 (p<.01), and HMT significantly showed the increase of ALP (p<.05) and DMP1 (p<.01) in the early stages. Micro CT scan analysis, both melatonin groups showed a significant increase of bone mineral density compare to Con in the early stage (p<.01). In histology, LMT considerably revealed the recovery of cortical area of damaged bone. Whereas, HMT showed a delay of recovery phase compared to LMT and Con. Based on these results, we suggest that melatonin has a therapeutic effect in the early stage of fracture healing. Nonetheless, excessive or long‐term treatment might be lead to a negative effect to fracture healing.
Fabrication of Three‐Dimensional Cellulose Macroporous Film for Biomedical Application
Authors: Shin Eun Joo , Choi Soon Mo , Oh Tae Hwan , Han Sung Soo
Published: June 2021

Cellulose is the most abundant naturally occurring polymer on earth produced by plants and bacteria that has been utilized in applications from paper and textiles to materials in wound healing. It has been employed in the form of membranes and bioadhesive cellulose gels as vascosurgical devices for investigations in bone tissue engineering and cartilage tissue engineering. In this work, we have focused on fabrication of cellulose scaffolds by NaCl leaching technique for bone tissue engineering. Ionic liqid(ILs) are considered as desirable green solvents because of their excellent dissolution ability, low vapor pressure, and easy of recycling. In methods based on the leaching of soluble particulates, the porosity can be effectively controlled by variation of the amount of leachable particles and the pore size of the porous structure can be adjusted independently by using particles of different sizes. The morphology and physical properties of cellulose scaffolds were investigated and in vitro experiment also carried out. The results were as follow: Porous film was perfectly contained interconnected porous network between 350~500μm in size. Cell viability of cellulose film was evaluated using a MTT assay for checking biocompatible substrate. Ionic liquid(1‐ally‐3‐methylimidazolium chloride: AmimCl) was found to be a powerful, nonderivatizing single‐component solvent for cellulose.
Dual physical cues of topological alignment and an electric field synergistically enhance myoblast differentiation
Authors: Ko Ung Hyun , Kim Mina , Bang Hyunseung , Park Sukhee , Shin Hyunjun , Shin Jennifer Hyunjong
Published: June 2021

For proper use in muscle tissue engineering, myoblasts need to be well differentiated to form functional myotubes. Therefore, in this study, we employ a couple of external physical environment cues, namely an aligned topological feature and an electric field (EF), to enhance the differentiation of myoblasts. Polycaprolactone (PCL) fibers were fabricated by electrospinning, with alignment precisely controlled by an asymmetric collector. EF was applied in a parallel or orthogonal direction to that of the aligned fibers to investigate the combinatorial effects of two different physical cues in myoblast differentiation. The results were analyzed by immunofluorescent images and real time PCR. From the results, Myoblasts cultured on aligned fibers were highly elongated along the fiber direction and exhibited high myotube density. Combinatorial stimulation of aligned fibers and EF simulation in parallel orientation had much enhanced myogenic differentiation, highlighting the directions of EF and fiber alignments are an important factor in maturation of the differentiated myoblasts.
Maternal WIC Participation Improves Breastfeeding Rates: A Statewide Analysis of WIC Participants
Authors: Metallinos‐Katsaras Elizabeth Sophia , Brown Lisa , Colchamiro Rachel
Published: June 2021

This study examines the association between length of exposure to WIC services and breastfeeding initiation/duration. All women with singleton live births, first certified into MA WIC prenatally or PP (2001–2009), whose infants had complete breastfeeding and covariate data (maternal race, age, education, smoking status, BMI, HH income and size, birthweight and sex) were included (n=122,506). Multivariate Logistic and General Linear Model Regressions were used to examine timing of WIC entry (i.e., trimester of prenatal or PP) in relation to: 1) breastfeeding initiation, 2) mean duration 3) durations of 3, 6 and 12 months. Among prenatal WIC entrants, first (vs. third) trimester entry was associated with a 10% higher likelihood for primiparous, and a 32% higher likelihood for multiparous mothers (p < .01) of initiating breastfeeding. Prenatal entrants were more likely than PP entrants (p < .0001) to initiate breastfeeding (13% for primi and 23% for multiparous). Prenatal WIC entrants breastfed 1.7 (primiparous), and 3.4 (multiparious) weeks longer than PP entrants (p < .0001). Among multiparous women, first trimester entry was associated a greater likelihood of breastfeeding for three (15% greater), six (25% greater) and 12 (33% greater) months compared to third trimester entrants (p < 0001). WIC improves breastfeeding rates among a low income diverse population of women.

Funding: MA Dept Pub Hlth
Obesity increases the severity of secondary bacterial coinfection following influenza virus infection
Authors: Karlsson Erik A , van De Velde Nicholas , McCullers Jon , Schultz‐Cherry Stacey
Published: June 2021

Obesity is a significant risk factor for influenza virus infection. However, little is known about obesity and secondary bacterial coinfections; the major cause of morbidity and mortality. Obesity increases inflammation, alters immune response and decreases wound repair in the lungs of obese mice infected with influenza virus, all risk factors for bacterial colonization. Therefore, we questioned the effect of obesity on secondary bacterial pneumonia. Infection of lean and obese mice with a nonlethal dose of influenza virus followed by a nonlethal dose of Streptococcus pneumoniae resulted in 100% mortality in obese mice by day 3 post bacterial challenge with no loss of lean controls. No differences were observed in viral titers between groups; however, lung bacterial titers were significantly increased in obese animals. Histological analysis revealed widespread damage to the lungs of obese mice. Obesity increases the severity and mortality from influenza‐associated complications and secondary bacterial pneumonia may be greatly enhanced in an increasingly obese human population. Further study is necessary to determine the mechanisms of increased susceptibility to influenza, secondary bacterial infection and possible therapeutic strategies in this expanding risk group.

Grant Funding Source: NIH NIAID contract number HHSN266200700005C and the American Lebanese Syrian Associated Charities (ALSAC)
Drinking water to dilute urine osmolality is associated with greater weight loss in pre‐adolescents eating lower glycemic foods
Authors: Stookey Jodi JD , Del Toro Rigoberto , Hamer Janice , Medina Alma , King Janet , Higa Annie , Ng Vivian
Published: June 2021

Drinking water appears to accelerate weight loss in adults consuming hypocaloric diets when the volume of water is over 1L/d or associated with decreases in urine osmolality. This study explored whether drinking water to dilute urine similarly accelerates weight loss in pre‐adolescents, and if the effect is mediated by cell hydration effects on insulin. Boys and girls (n=25, 9–12y, BMI>;85th%) were randomly instructed to drink enough water to dilute urine or drink water following thirst. All were instructed to avoid other beverages and high glycemic foods. Random saliva insulin, urine osmolality and body weight were assessed weekly for 8 weeks. In completer analyses, participants who ate high glycemic foods at >;50% of meals did not lose significant weight over 8 weeks (−0.4 (0.5)kg). Participants who had high glycemic foods at <25% of meals and urine osmolality <500 mmol/kg over time had significantly lower saliva insulin over time (13(2) vs. 22(3) pmol/L) and greater weight loss (−3.3 (1.2) kg vs. −2.2 (0.9)kg) than participants who also adhered to the study diet but drank to thirst and maintained elevated urine osmolality (887 (27) mmol/kg). Urine osmolality significantly modified the effect of saliva insulin on weight loss. Drinking water to dilute urine may accelerate weight loss for overweight adolescents by limiting insulin levels. Further work is needed to characterize this effect.
Effect of Two Oat‐based Breakfast Cereals on Appetite, Satiety, and Food Intake
Authors: Rebello Candida Joan , Johnson William , Martin Corby , Bordenave Nicolas , van Klinken B. Jan Willem , O'shea Marianne , Chu YiFang , Greenway Frank
Published: June 2021

Objective

To compare the effect of two oat‐based cereals on appetite, satiety, and food intake

Methods

48 healthy individuals, ≥18 years of age were enrolled in a randomized, controlled, crossover trial. Following an overnight fast, subjects consumed either oatmeal or a ready‐to‐eat oat‐based breakfast cereal (RTEC) in random order at least a week apart. Each breakfast contained 363kcals (250kcals cereal, 113kcals milk). Visual analogue scales measuring appetite and satiety were completed at baseline and postprandial. Lunch was served four hours after breakfast. The molecular weight, radius of gyration and viscosity of oat fiber (β‐glucan) were determined. Appetite and satiety responses were analyzed by area under the curve. Food intake and β‐glucan properties were analyzed using t‐tests or chisquare analysis.

Results

Oatmeal resulted in greater increase in fullness and greater reduction in hunger, desire to eat, and prospective intake compared to RTEC (p<0.002 for all). Food intake at lunch was lower after eating oatmeal compared to RTEC (p<0.0123). β‐glucan in oatmeal had higher molecular weight (p<0.0001), radius of gyration (p<0.0001) and viscosity (p=0.03) than in RTEC.

Conclusions

Oatmeal suppressed appetite, increased satiety and reduced food intake compared to RTEC. The physicochemical properties of oat fiber are important factors affecting satiety and food intake. Study funded by PepsiCo
Human Airway Secretions Inhibit Pseudomonas aeruginosa Activity: Effects on Survival, Growth, and Flagellar Motility
Authors: Weitz Anna K , Willborg Jessica L , Hinz Sandra M , Bankers‐Fulbright Jennifer L
Published: June 2021

Pseudomonas aeruginosa is a ubiquitous opportunistic pathogen that is a leading cause of morbidity and mortality in patients with cystic fibrosis (CF). The relative selectivity of P. aeruginosa colonization in CF patients suggests that the CF airway, in contrast to normal airways, is particularly hospitable to P. aeruginosa. One likely possibility for this difference is that normal but not CF airways secrete compounds that attenuate the virulence of P. aeruginosa and prevent colonization. In this study, we examined the ability of normal airway epithelial secretions to inhibit two properties of P. aeruginosa associated with colonization: proliferation and flagellar motility. For these initial experiments, we used apical secretions from polarized Calu‐3 cell monolayers and the P. aeruginosa strain PA14. Treatment of PA14 cells with Calu‐3 secretions dramatically reduced both average swimming speed (30 vs. 15 μm/sec) and the number of motile bacteria (56% vs. 42%). Inhibition of PA14 growth was not seen after 24‐hours of incubation with Calu‐3 secretions, in contrast to previous reports. Our preliminary attempts to identify the active component(s) in Calu‐3 secretions suggest that one or more proteins >;50 kDa are responsible. We conclude that normal airway epithelial secretions directly inhibit certain P. aeruginosa functions associated with airway colonization.

This project was funded by the Augsburg College Undergraduate Research and Graduate Opportunities (URGO) Office and Sundquist Scholars Program.
Colonic MUC2 mucin regulates the expression and antimicrobial activity of β‐defensin 2
Authors: Cobo Eduardo Ruben , Kissoon‐Singh Vanessa , Trusevych Elizabeth , Moreau France , Chadee Kris
Published: June 2021

The MUC2 mucus layer is the first line of host defense in the gut. How MUC2 interacts with antimicrobial peptides in host defense is not well understood. In this study we investigated the interactions between MUC2 and β‐defensin. Of the colonic cells tested, β‐ defensin 2 expressions was the highest in MUC2 producing human LS 174T and the lowest in Caco‐2 cells. Similarly, expression of murine β‐defensin 4 (orthologous to human β‐defensin 2) was low in the colon of Muc2−/−mice as compared to Wt. Purified MUC2 attenuated the stimulation of β‐defensin as IL‐1β and sodium butyrate induced the expression of β‐defensin in Caco‐2, but not LS 174T cells. The antimicrobial activity of β‐defensin 2 differed among enteric bacteria; Escherichia coli were more susceptible than Bacteroides vulgatus and Clostridium difficile in killing assays. Our studies revealed that MUC2 served as a food source for enteric bacteria, which explains why Muc2−/− harbored less commensal Bacteroides and Firmicutes spp. Mechanistically, MUC2 N‐ and O‐linked oligosaccharides bound bacteria and protected them against β‐defensin 2 antimicrobial activities. MUC2 protected the microbiota by serving as a food source and by inhibiting the antimicrobial activity of β‐defensin. When the mucus barrier is compromised, β‐defensin kills susceptible bacteria whereas β‐defensin resistant bacteria may colonize and cause disease.
The role of Shiga toxin in promoting transepithelial migration of neutrophils
Authors: Boll Erik Juncker , Szabady Rose , Jandhyala Dakshina , Thorpe Cheleste , McCormick Beth
Published: June 2021

The Shiga toxin (Stx)‐producing E. coli are human pathogens of significant importance. Among these bacteria, enterohemorrhagic E. coli (EHEC) have been most frequently associated with outbreaks of foodborne illness, causing hemorrhagic colitis that can lead to severe systemic disease. Recently, a major outbreak in Germany was caused by an enteroaggregative E. coli (EAEC) strain that had acquired the Stx genes. Clinical data from patients suggest that inflammatory responses may play an important role during both EHEC and EAEC disease. Here, we show that EHEC induces transepithelial migration of neutrophils (PMNs) across polarized colonic epithelial cells. Furthermore, deletion of the Stxencoding genes significantly attenuates this inflammatory event. Stx has been implicated in other inflammatory pathways, including up‐regulation of pro‐inflammatory cytokines in intestinal cells via activation of the ribotoxic stress response (RSR). We have found that inhibition of ZAK, a host cell kinase that is required to initiate the Stx‐induced RSR, inhibits the ability of EHEC to induce PMN transepithelial migration, similar to the effects of Stx deletion. We conclude that Stx‐mediated activation of the RSR likely plays a key role in EHEC‐induced PMN transepithelial migration. Further research will examine whether Stx plays a similar role in inducing inflammatory PMN migration to the German outbreak strain.
Anatomy Academy exposes undergraduate and medical students to all ACGME core competencies through an experiential learning environment
Authors: Wisco Jonathan J. , Diaz Molly M. , Padilla Jessica , Ojukwu Kenechukwu
Published: June 2021

In 1999 the Accreditation Council for Graduate Medical Education (ACGME) introduced six Core Competencies – Patient Care, Medical Knowledge, Practice‐based Learning and Improvement, Interpersonal and Communication Skills, Professionalism, Systems‐based Practice – for which all residents, regardless of specialty, are expected to be competent. The shift in residency education to meet the ACGME requirements has caused a domino effect in how schools approach medical education. We have developed a program called Anatomy Academy (AA) wherein undergraduate, medical, dental, allied health and education students teach anatomy, physiology and nutrition concepts to 5th and 6th grade children as an educational intervention to fight childhood obesity. We found, through IRB approved self‐efficacy evaluations and prompted written reflections, that the experiential learning environment benefits all participants in the program through vertical and horizontal learning and mentoring experiences and exposure to all 6 core competencies. We propose that AA, or similar programs, have an essential role in medical education.

Grant Funding Source: The Albert Schweitzer Fellowship and the UCLA Monica Salinas Fellowship
A Modern Distributed Learning Histology Course with Virtual Lectures and Labs
Authors: Ogilvie Robert , Sawyer Roger
Published: June 2021

A successful and popular Distributed Learning Histology Course was developed at the University of South Carolina as a result of collaboration between Roger Sawyer, Professor of Biology at the University of South Carolina and Robert Ogilvie, Professor Emeritus at the Medical University of South Carolina. The fully online upper level course for college juniors, seniors and graduate students includes narrated video lectures and the utilization of two virtual lab resources. The lectures are available to students through an Adobe Connect Server at the University of South Carolina. All lectures include interactive questions at the end for self assessment. All quizzes and exams are administered online. PDF documents are provided to the students of the static lecture slides with the text of the narration in the online lectures for study offline. The virtual lab resources are WebMic and the use of Virtual Slides managed by Neuroinformatica and Biolucida Cloud (MBFbioscience.com). The presentation will include the set up of the five modules in the course, how the resources were developed, the design of the course management interface and the experience of having taught the course online for four semesters. This talk will also include the investment of time to develop such a course, the tools that are used, how the course has evolved over four semesters and the challenges to make it engaging, including minimizing cheating.
Comparative anatomy of mammalian and primate facial muscles and evolutionary genetics of atavistic muscles in humans with trisomy
Authors: Ziermann Janine , Diogo Rui , Bhatia Naina
Published: June 2021

Previous studies have suggested that modern humans with genetic disorders such as trisomy (e.g., 13, 18 and 21) have several muscular abnormalities and ‘atavisms’. We have explored the comparative and ontogenetic context of these abnormalities by examining a wide range of primates and other mammals, and our comparative studies suggest that actually only a few of the reported muscular abnormalities represent true evolutionary ‘atavisms’, e.g., the presence of contrahentes in the hand, and of the facial muscle platysma cervicale. Interestingly, in karyotypically ‘normal’ modern humans these muscles are also present early in ontogeny but then usually disappear before birth. This suggests that at least some of the muscular ‘atavisms’ in trisomic individuals are the result of delayed/arrested development. Our contribution investigates the evolutionary and phylogenetic context of these muscular abnormalities and includes new data about anatomical and genetic studies of mice models for Down Syndrome (trisomy 21) that provide crucial information for a better understanding of human medicine, anomalies, variations, and evolutionary history.
How Good are Mice and Monkeys as Models for Human Face Transplants? Comparative Physiological Perspectives on Myosin Fiber Types
Authors: Burrows Anne M , Durham Emily L , Matthews Lea C , Smith Timothy D , Parr Lisa A
Published: June 2021

Human face transplants are becoming a viable surgical option for patients with severe facial injuries. Reanimation of the muscles of facial expression is a desired outcome and both murines and rhesus macaques are candidate animal models of surgical protocols. However, it is not clear how appropriate these models are for the unique structural and functional complexity of the human face. The present study examines myosin fiber types and select peripheral characteristics of the facial nerve in laboratory mice and rhesus macaques in order to assess their suitability as models of human facial transplants. Samples of the zygomaticus major and orbicularis oris muscles containing ends of the facial nerve were gathered from three mice, three rhesus macaques, and three human cadavers for histochemical and immunohistochemical processing. Proportions of fast to slow twitch myosin fibers and morphometric characteristics of the facial nerve were compared among the species. Results show that like humans, mice and macaque facial musculature is dominated by fast twitch myosin fibers but many facial nerve characteristics differ among these species. Physiologically, the macaque may be the better model facial transplants, especially with respect to facial nerve characteristics. Murines may be confounding as a model due in part to the unique musculature and large number of facial nerve axons associated with the highly mobile whiskers.

Support from the Samuel and Emma Winters Foundation and NIH MH082282
Structural analyses of the developing human postcranial skeleton using high‐resolution CT
Authors: Ryan Timothy M. , Raichlen David A. , Gosman James H.
Published: June 2021

The initiation and maturation of human walking combined with increasing body mass during ontogeny contribute to major changes in the mechanical loading of the postcranial skeleton during childhood and adolescence. Quantitatively tracking associated morphological changes provides important insights into functional bone adaptation and the evolutionary morphological changes associated with the evolution of upright bipedal walking in hominins. MicroCT is a powerful tool for analyses of bone development that allows non‐destructive access to internal bone structure. This study uses microCT to examine the developmental trajectories of cortical and trabecular bone structure in the postcranial skeleton of humans from birth to adulthood. MicroCT scans were collected for the femur, tibia, humerus, and lumbar vertebrae of 70 juvenile and adult humans with voxel sizes between 0.017 to 0.113 mm. Cortical bone follows broadly similar growth trajectories into adulthood in the femur and tibia, but not in the humerus, while trabecular bone displays a more complex pattern. Most trabecular variables follow unique trajectories reflecting localized bone growth and (re)modeling processes that approach adult values after about 10 years of age. While clearly interrelated, cortical and trabecular bone follow distinct growth trajectories likely due at least in part to divergent biomechanical stimuli.
What do human parasites with a chloroplast anyway?
Authors: Striepen Boris
Published: June 2021

Apicomplexan parasites are a major threat to human health causing malaria and a variety of AIDS associated opportunistic infections. One of the most promising targets for chemotherapeutic intervention for this group of pathogens is the apicoplast. The apicoplast is a unique parasite organelle that was derived from a red algal endosymbiont. Genome analyses suggest that the apicoplast is engaged in a variety of biosynthetic activities that could be targeted for drug development. Using Toxoplasma gondii as a genetic model organism we are dissecting the apicoplast metabolism to identify the most effective choke points. Taking a broader biological view we are interested to understand which of the endosymbiont's functions is most critical and the reason for the continued presence of a plastid long after the loss of photosynthesis. Our current work is focused on the mechanisms and importance of parasite lipid synthesis in particular that of fatty acids and isoprenoids.
Analysis of RNA polymerase II transcription initiation and elongation complexes
Authors: Buratowski Stephen
Published: June 2021

Our lab uses a variety of approaches to try to understand how RNA polymerase II initiates, synthesizes, and terminates transcription. We are also very interested in how transcription is coupled to the processes of RNA processing and chromatin modification. The yeast Saccharomyces cerevisiae is an outstanding model system, allowing genetic, genomic, molecular, and biochemical approaches to be effectively combined. In collaboration with Dr. Jarrod Marto (HMS/DFCI), we are using quantitative proteomics experiments to analyze the proteins associated with RNA polymerase II complexes assembled on naked and chromatinized templates. We also continue our work on how the phosphorylation patterns on the C‐terminal domain (CTD) of RNA polymerase II subunit Rpb1 are used to recruit important RNA processing, chromatin‐modifying, and termination factors at specific points of the transcription cycle. I will be presenting some of our recent results describing the communication between RNA polymerase II, its associated factors, and the chromatin template.
Small molecules, toxins and cell death pathways
Authors: Hung Deborah T
Published: June 2021

Many bacterial pathogens first interact with the host through elaboration of toxins by secreting toxins that are taken up by the host and go on to disrupt essential host cellular functions. This process is the result of a remarkable co‐evolutionary process between the pathogen and the host. We will discuss chemical biological approaches to studying the interaction between a pathogen and a host and the simultaneous application of small molecules and toxins as probes that perturb host cellular processes. These perturbations can be used to reveal important cell biology including cell death pathways in response to pathogen stimulation. We will discuss the example of anthrax toxin, which is elaborated by the bacterial pathogen Bacillus anthracis.
Exosomal media enhances proliferation, migration, and invasion in triple negative breast cancer
Authors: Johnson KiTani Parker , Stoute Diana C , Yearby Letitia , Beverly Gabriel , Skripnikova Elena , Ochieng Josiah
Published: June 2021

Patients who present with the subtype of breast cancer called triple negative breast cancer (TNBC) have poorer outcomes than patients with less aggressive subtypes of breast cancer. To better understand the proliferation, migration, and invasion associated with TNBC, we evaluated the microenviroment of the TNBC cells using noncancerous breast epithelial cell line MCF‐10A. Exosomes secreted from MCF‐10A when in crisis cells enhances growth, motility, and invasion by promotion signals and prepares metastatic niches both in vitro and in vivo. Our laboratory investigated this phenomenon using TNBC cell lines MDA‐MB‐231 and MDA‐MB‐468. Preliminary data suggests that this exosomal media contains biomolecules that enhance proliferation, migration, and invasion of TNBC cells. Here we will report our findings on exosomal media promoting the proliferation, migration, and invasion in both MDA‐MB‐231 and MDA‐MB‐468 cells. Gene expression is modified when these cells are exposed to exosomal media, and finally, we demonstrate that exosomal media has a significant impact in enhancing the growth of both MDA‐MB‐231 and MDA‐MB‐468 cells in vivo over 90 days. Better understanding the microenvironment of the TNBC cells will aid us in identifying novel targets for pharmacological intervention.