bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of the scaffold protein striatin in regulating the excitation‐contraction coupling in cardiomyocytes
Authors: Nader Moni , Khalil Bariaa , Abu‐Zaid Ahmed , Inaya A'man , Bakheet Dana , Dzimiri Nduna 
Published: June 2021

Striatin (STRN) is a multivalent protein with dynamic domains including caveolin (Cav) and calmodulin (CaM) binding sites; both of which are key regulators of the L‐type calcium channel (LCC). We have previously reported that the formation of the STRN/Cav/CaM complex was calcium sensitive and that overexpression of striatin resulted in a sustained elevation of KCl‐induced intracellular calcium increase. We aimed, in this study, to show whether STRN interacts with LCC and PP2A to regulate cardiomyocyte contractility. Herein we report that both protein phosphatase 2A (PP2A) and the LCC were associated with STRN/Cav/CaM complex and that the interaction between all these components was calcium sensitive (abolished by calcium chelator EGTA). In addition, we also show that overexpression of striatin (adenoviral delivery) in cultured cardiomyocytes increased the rate of contraction by ~ 3 fold when compared to control cells (non‐target adenovirus). Preliminary data showed that knockdown of striatin (shRNA targeting STRN) enhanced the interaction of CaM and Caveolin‐3 suggesting a central role for STRN in articulating the STRN/Cav/CaM/LCC/PP2A complex. Collectively, our data suggest that striatin may emerge as a novel regulator of the L‐type calcium channel in cardiomyocytes and consequently regulate their contractility.This work was supported by an operating grant from KFSHRC.
LPS induces the same prostaglandins (PGs) in warm and cold environments, but thermal responses to PGs strongly depend on ambient temperature (Ta)
Authors: de Oliveira Cristiane , Nucci Tatiane B , Eales Justin , Dragic Alexander S , Pan Jennifer , Patel Shreya , Pakai Eszter , Brose Stephen A , Golovko Michail Y , Steiner Alexander A , Romanovsky Andrej A 
Published: June 2021

Rats respond to iv LPS with a complex thermoregulatory response, which is represented mostly by fever at a neutral Ta, but mostly by hypothermia at a subneutral Ta. Both the febrile and hypothermic components of this response are mediated by PGs, but the exact mechanism of the fever‐hypothermia switch is unknown. Wistar rats were injected with LPS (10, 100 or 1000 μg/kg iv) at a neutral (30°C) or subneutral (20°C) Ta. At 30°C, the febrile components of the response to each LPS dose were more pronounced; at 20°C, the hypothermic components were predominant. At either Ta, LPS caused a dose‐depended increase in plasma PGs within all five cascades (PGE2, D2, F2á, I2 and TXB2), whether measured by ELISA or LC/MS/MS. Irrespective of the method, we found no difference in the plasma response of any individual PG to any dose of LPS at 30°C vs 20°C. We then studied thermoregulatory responses of rats to iv PGs (0.8 μmol/kg, administered as albumin complexes) at 30 and 20°C. Only PGE2 caused a statistically significant fever, and this response was unaffected by Ta. Several PGs, including E2, D2 and I2, caused hypothermia, and this response was restricted to the subneutral conditions. We conclude that, regardless of Ta, LPS causes the same systemic PG response. The fever‐hypothermia switch involves LPS‐induced PGE2, D2 and I2 causing hypothermia in a subneutral (but not neutral) environment.Support: NS041233, NS064480, 11SDG4880051
Short‐term training alters the control of mitochondrial respiration rate before maximal oxidative ATP synthesis
Authors: Layec Gwenael , Haseler Luke J , Hoff Jan , Hart Corey R , Liu Xin , Jeong Eun‐Kee 
Published: June 2021

BackgroundThere has not been a study that has directly assessed temporal changes in mitochondrial oxidative capacity and metabolic control as a consequence of short‐term exercise training in vivo.MethodsWe used 31P‐magnetic resonance spectroscopy (31P‐MRS) to examine the effect of short‐term plantar flexion exercise training on phosphocreatine (PCr) recovery kinetics and the control of respiration rate. To this aim, we investigated 12 healthy men experienced with this exercise modality (TRA) and 8 time‐control subjects (TC).ResultsAfter 5 days of training, maximum work rate during incremental plantar flexion exercise was significantly improved (P < 0.01). During the recovery period, the maximal rate of oxidative ATP synthesis (PRE: 28 ± 13 mM.min−1; POST: 26 ± 15 mM.min−1) and the PCr recovery time constant (PRE: 31 ± 19 s; POST: 29 ± 16) were not significantly altered. In contrast, the Hill coefficient (nH) describing the cooperativity between respiration rate and ADP was significantly increased in TRA (PRE:nH =2.7 ± 1.4; POST: nH =3.4 ± 1.9, P < 0.05). Meanwhile, we did not observe any systematic variation in any of these variables in the TC.ConclusionThis study reveals that 5 days of training induces rapid adaptation in the allosteric control of respiration rate by ADP before any substantial improvement in muscle oxidative capacity.
The pattern of change in skeletal muscle oxidative injury and non‐heme iron during aging differs between fast and slow muscles
Authors: Receno Candace N , Cowley Patrick M , Cromer Alray , Liang Chen , DeRuisseau Keith C 
Published: June 2021

The aging‐related elevation in skeletal muscle non‐heme iron (NHI) is thought to be a contributing factor to the development of oxidative stress and sarcopenia. However, the iron status of aging slow twitch muscle has not been reported. This study examined the association between NHI and oxidative injury among two muscles that show a divergent pattern of aging‐related muscle atrophy; the fast twitch tibialis anterior (TA) and slow twitch soleus (Sol). Male F344BN rats were studied at 8, 18, 28, and 36 months of age. The animals were anesthetized and muscles were harvested for analysis of NHI and oxidative injury measures. The TA mass was greater than the Sol (p<0.05) and showed atrophy beginning at 28 months compared to 18 month values (p<0.05). The Sol showed atrophy only at 36 months (p<0.05). NHI concentration (nmol/gww) of the Sol was increased at 36 months (95.4±9.3; p<0.05) compared to the other age groups and coincided with the decline in muscle mass. The TA NHI was also increased at 36 months (46.3±8.2; p<0.05); after the onset of muscle atrophy and to a lesser extent than that of the soleus (p<0.05). Lipid peroxidation was unchanged in the TA (p>;0.05) but increased (p<0.05) in the Sol at 36 months compared to 8 and 18 month groups. In summary, elevations in NHI concentration and oxidative injury were better aligned with the Sol pattern of atrophy than the TA in response to aging.Supported by NIH 5R03AG032033 (KCD)
Intracellular ATP modulates vascular distinctive P2X receptors in rat arterial smooth muscle
Authors: Morita Hiromitsu , Yoshimoto Shohei , Takeuchi Hiroshi , Abe Kihachiro , Hirata Masato , Ito Yushi 
Published: June 2021

The extracellular nucleotide sensitive P2 receptor comprises two different groups: ionotropic P2X and metabotropic P2Y receptors. It is generally considered that the P2X receptor lacks intracellular ATP binding sites.In rat arterial myocytes, however, we identified that P2X1 and 5 receptors form a heteromultimer and found that its activation kinetics is modulated by cytosolic ATP, since a significant decrease was observed in desensitization of P2X receptor current evoked by repeated application of α,β‐methylene ATP (10μM) at 5 minute intervals with increasing intracellular ATP concentration (0, 2 and 5mM to 52.4±6.0%, 45.7±5.4% and 33.5±3.0%, respectively: n=5–13). In contrast, ADP and AMP did not modulate the current. Similar effects were observed in rat cerebral and mesenteric artery myocytes.Therefore, we performed a homology search for ATP‐binding motifs in P2X receptors, and found P2X1 and 5 receptors have the motifs at the pore‐forming transmembrane regions. In addition, we confirmed the co‐localization of P2X1 and 5 receptor proteins in each arterial tissue by RT‐PCR, western blot and immunostaining analyses.These results suggest that P2X1 and 5 receptors may play important roles in metabolic regulation in conditions such as hypoxia.
Analysis of high altitude cognitive task performance on multiple tests
Authors: Issa Amine N , Wentz Robert J , Herman Nicole M , Taylor Bryan J , Summerfield Doug T , Kasak Alexander J , Johnson Bruce D 
Published: June 2021

BackgroundIt is documented that cognitive performance can diminish with altitude, but the sensitivity of specific tests have not been investigated. Our objective was to assess and compare cognitive performance from several tests and relate this to quality of sleep and acute mountain sickness (AMS).MethodsDuring an Everest expedition, 3 cognitive tests (Stroop, Trail Making, and a proprietary motor accuracy test) were used along with a questionnaire to assess sleep and AMS. Six athlete climbers and 9 core team members were assessed pre and post‐expedition and at several time points during the expedition (up to 17,500 ft).ResultsTo normalize for individual differences, scores were assessed as % change from baseline. There was no difference in the variation between repeated attempts in a single testing session (0.19<p<0.87), demonstrating that each test was reproducible. There was no decrement in test scores with altitude, nor was there an association with reported sleep quality. The Stroop performance was associated with AMS (p<0.05) and trending with headache (p< 0.15). The in‐house motor test trended towards an association with AMS and headache (p<0.15). However, the trail making test was not associated with AMS/headache.ConclusionWith appropriate acclimatization, cognitive performance is maintained at altitude but is linked to presence of headache and AMS. Mayo Clinic and TNF.
NO regulation of Na,K‐ATPase in ocular ciliary epithelium involves Src Family Kinase
Authors: Shahidullah Mohammad , Mandal Amritlal , Wei Guojun , Delamere Nicholas A 
Published: June 2021

The nitric oxide (NO) donor SNP reduces aqueous humor (AH) secretion in the isolated porcine eye. SNP inhibits Na,K‐ATPase activity in AH‐secreting tissue, nonpigmented ciliary epithelium (NPE), through a cGMP/PKG‐mediated pathway. Here we study the role of Src family kinases (SFKs) in the Na,K‐ATPase activity response to NO.NPE was cultured and Na,K‐ATPase activity measured by quantification of ATP hydrolysis in NPE lysate and by estimating ouabain‐sensitive potassium (86Rb) uptake in intact NPE. Protein phosphorylation was examined by western blot.SNP inhibited Na,K‐ATPase activity by >;35% but did not change Ser16 phosphorylation of the Na,K‐ATPase α1 subunit or the abundance of α1 protein available for surface biotinylation. The SFK inhibitor PP2 prevented both SNP and 8‐Br‐cGMP‐induced reduction of Na,K‐ATPase activity. SNP and 8‐Br‐cGMP increased phosphorylation of SFK, ERK1/2 and p‐38 MAPK. PP2 prevented the responses. The ERK1/2 inhibitor U0126 prevented SNP‐induced ERK1/2 and p‐38 phosphorylation but did not suppress SNP‐induced SFK phosphorylation or Na,K‐ATPase activity reduction. SNP caused detectable phosphorylation of Na,K‐ATPase α1 at Tyr10.NO‐induced inhibition of Na,K‐ATPase activity appears to depend on SFK activation that occurs via cGMP/PKG.Funding: NIH Grant EY006915.
Kidney blood flow modeled from structural morphology of renal vasculature in the rat
Authors: Bukowy John , Mescam Muriel , Cowley Allen W , Beard Daniel A 
Published: June 2021

The kidney extracts and excretes urea and other metabolic wastes from the blood, and maintains levels of plasma salt and hydrogen ions by differentially regulating the concentration of these ions in the urine. Since solute and water transport in the kidney is tied to the control and distribution of flow in the vasculature of the kidney, an understanding of renal microcirculatory dynamics is needed to understand the physiological function of this organ.Using dimensional and ordering data obtained from a microtomography (Micro‐CT) study of structural morphology of renal vasculature, separate functions describing the transit time distribution of blood flow through the arterial and venous trees were derived. Separately, three regional microcirculatory models (cortical, juxtamedullary, and shunting) were used to connect the arterial and venous trees. Simulation of the combined model yields a renal intravascular washout function that describes the transit of blood throughout the kidney. Using optimization methods, simulations were fit to experimental data obtained from rat kidney washout studies to estimate functional blood flow to the three microcirculatory beds. This modeling approach can be applied to analyzed data from imaging modalities using contrast measurements in animal studies as well as the clinical setting.
Tendon collagen fibrils ‐ Continuity and mechanical properties
Authors: Svensson Rene Brüggebusch , Herchenhan Andreas , Kovanen Vuokko , Qvortrup Klaus , Magnusson S. Peter 
Published: June 2021

PurposeTendon force transmission depends on the length and mechanical behavior of collagen fibrils, two poorly understood parameters.MethodsCollagen fibrils from rat‐tail tendons (RTT) and human patellar tendons (HPT) were mechanically tested to failure using atomic force microcopy (AFM). The effect of cross‐link stabilization by NaBH4 in RTT was investigated. Continuity and structure of HPT fibrils was determined by electron microscopy serial sectioning (FIB‐SEM).ResultsFailure stress and high‐strain modulus were greater for the HPT (540±140 MPa, 4.3±1.4 GPa) than RTT fibrils (200±110 MPa, 1.4±0.7 GPa) (p<0.001) (see fig.). NaBH4 had no effect on RTT fibril mechanics. In contras, fascicles showed higher failure stress (58±18 MPa vs 35±11 MPa, p=0.02) and reduced failure strain (5.0±0.8% vs 9.7±4.5%, p=0.05). A total of 1800 HPT fibrils were traced through 25μm deep FIB‐SEM stacks (total length = 45 mm), and only one fibril end, 4 fibril fusions and 3 fibril loops were observed.ConclusionDifferences between RTT and HPT fibril properties are likely caused by greater cross‐link maturity in HPT, but seem unrelated to cross‐link lability since NaBH4 had no effect on RTT fibrils. That reduction did have an effect at the fascicle level indicates the presence of reducible interfibrillar bonds. HPT fibril length data suggests that fibrils rarely end, but rather fuse to form a functionally continuous structure.
Obstetrical practices but not gestational metabolic abnormalities are associated with delayed onset of lactogenesis
Authors: Ley Sylvia H , Hanley Anthony J , Zinman Bernard , O'Connor Deborah L 
Published: June 2021

Women with pre‐existing diabetes and obesity experience delayed onset of lactogenesis II (DOLac), but the impact of metabolic abnormalities developed during pregnancy on DOLac is unclear. We aimed to investigate the associations of metabolic status assessed during pregnancy with DOLac (onset of lactogenesis II ≥72 h postpartum). Participants (n=177) underwent a 3‐h oral glucose tolerance test at 30 (25th, 75th %tile: 29, 32) weeks gestation, and follow‐up interviews were conducted at 1, 3, and 7 d postpartum. Of 177, 98 (55.4%) women experienced DOLac. Gestational metabolic abnormalities, including gestational diabetes, insulin resistance (HOMA‐IR) and lower insulin sensitivity (Matsuda index), were not associated with DOLac. However, risks for DOLac were increased among women who had an unscheduled C‐section (OR 2.24 [95% CI 1.02, 4.92] vs. spontaneous delivery) and delayed initiation of breastfeeding (2.30 [1.09, 4.86] comparing ≤1 vs. >;2 h) with adjustment for age and ethnicity. Further, women who had an unscheduled C‐section put their infant to the breast at 2.0 (25th, 75th %tile: 1.0, 5.1) h, while women who had a spontaneous delivery did so at 1.0 (0.8, 2.0) h. In conclusion, gestational metabolic abnormalities are not associated with DOLac, but obstetrical practices including unscheduled C‐section and delayed timing of breastfeeding initiation increase risk for DOLac.Funding: CDA, CFDR, CIHR
Consumer attitudes and misconceptions of foods with sodium claims: Results of a randomized mock label experiment
Authors: Wong Christina L. , Arcand JoAnne , Mendoza Julio , Qi Ying , L'Abbé Mary R. 
Published: June 2021

In light of the public health priority to reduce dietary sodium, we evaluated consumers’ attitudes and understanding of permitted sodium claims on food labels. Online panellists were exposed to 4 identical mock canned soup labels, in random order, with the same Nutrition Facts table which differed only by the claim it carried. We tested 3 types of sodium claims (nutrient content (NC), function, disease risk reduction (DRR)) and a ‘tastes great’ claim acting as a control. Overall, all sodium claims resulted in higher ratings in attitudes toward the claim (i.e. attractiveness, clarity and credibility), attitudes towards the product (i.e. perceived healthiness) and purchasing intentions compared to the control claim (p<0.001). The NC and DRR claims were consistently rated the highest and similar to each other, yet regulatory criteria for foods to carry such claims differ greatly. Sodium claims, that do not mention health or disease, still infer health benefits. In addition, panelists attributed additional health benefits to products carrying sodium claims, beyond the well established relationship between sodium and hypertension, such as for weight loss, diabetes and constipation (p<0.001). This study demonstrates the need for additional efforts to educate consumers on common misconceptions of the benefits of sodium reduction, especially as population wide sodium reduction initiatives move forward.Grant Funding Source: AFMNet; CIHR operating grant/Canadian Stroke Network; CIHR Strategic Training Program in Public Health Policy (CW), CIHR Strategic Training in Population Intervention for Chronic Disease Prevention: A Pan‐Canadian Program (Grant#53893) (CW); Ontario Graduate Scholarship (CW); Heart & Stroke Foundation of Canada Postdoctoral Fellowship (JA); University of Toronto McHenry Chair (ML)
Development and Implementation of Educational Outreach Programs for Oakland and Neighboring Communities
Authors: Puder Barb , Neal Jasmine 
Published: June 2021

Community members are becoming more proactive in their health care decisions, and many individuals are seeking more information regarding the function and maintenance of various body systems, disease prevention, and lifestyle choices that can impact their personal health. In turn, many universities have mission statements and goals to create community connections and provide educational programs on various health related topics. To meet the needs of community and university members, educational outreach programs can be established. Several outreach programs regarding brain health and safety have been created for Oakland area school children in grades K‐12 and an educational brain event for families and community members. The K‐12 outreach programs are designed within the needs of the curriculum content and grade level of the students. Classroom teachers are consulted for topic requests and length (time) of program that fit into their lesson plans and schedules. Programs vary from 1 hour to several hours to a 4 week mini course and cover topics ranging from neuroanatomy to sensory systems to drug effects on the nervous system.Saturday outreach events are designed to be family friendly and serve to educate both children and adults through interactive hands‐on poster stations presented by university students and lectures by selected invited guest speakers. Assessments from all programs are administered in the form of pre and post tests for K‐12 programs and surveys for participants of the Saturday community educational events.
How does household composition affect purchases of grainbased desserts?
Authors: Mathias Kevin Clark , Ng Shu Wen , Popkin Barry 
Published: June 2021

Grain‐based desserts (GBD) (e.g., cakes, cookies and pies) are the largest source of solid fats and the second largest source of added sugars in the US diet. Given that over 70% of GBD are purchased from stores, identifying factors (e.g., composition of children and adults living in a household) that affect household purchases of GBD is essential for decreasing intake of solid fats and added sugars. Quarterly store purchases of ready‐to‐eat GBD from 61,658 households participating in the 2011 Nielsen Homescan panel were analyzed using random effects models. The average purchase of GBD per day was 115 kcal among men living alone, 91 kcal among women living alone, 155 kcal for households with multiple adults and no children, 139 kcal for households with one adult and children, and 178 kcal for households with multiple adults and children. Among households of multiple adults without children, purchases of GBD increased by 19 kcal/additional adult. Among households with one adult and children, purchases of GBD increased by 19 kcal/additional child. Among households of multiple adults and children, purchases of GBD increased by 12 kcal/additional child and 19 kcal/additional adult. These results show that within household categories, increasing the number of individuals does not substantially increase the GBD purchased by a household, indicating that smaller households have larger amounts of GBD available to each person.Grant Funding Source: Robert Wood Johnson Foundation Grant 70017; National Institutes of Health R01‐HD030880 R01‐ HL104580 R01‐HL114091 R01‐HL108427.
Key markers associated with intestinal adaptation in pediatric short bowel syndrome
Authors: Naberhuis Jane Kelly , Tappenden Kelly Anne 
Published: June 2021

Administration of partial enteral nutrition (PEN) and trophic peptides, such as glucagon‐like peptide‐2 (GLP‐2), are emerging strategies for stimulating structural and functional aspects of intestinal adaptation in individuals with intestinal failure. To investigate the temporal sequence of events associated with PEN and/or GLP‐2‐mediated intestinal adaptation following massive small bowel resection, neonatal piglets underwent an 80% jejunoileal resection (n=72) and were randomized to 1 of 4 treatment groups using a 2×2 factorial model with total parenteral nutrition (TPN) or TPN+PEN and placebo or GLP‐2. Piglets were euthanized 4h, 48h or 7d after surgery and 93 variables of adaptation were analyzed by principal component analysis (PCA). Maximal variation was accounted for by small intestinal proliferation, apoptosis and crypt depth when all time points were pooled. The main factors accounting for variance shifted from crypt depth at 4h, to small intestinal nutrient transport and cellular proliferation at 48h. By d7, mucosal architecture, epithelial proliferation and nutrient transport accounted for maximal variation. These results indicate that structural markers of adaptations precede those of functional adaptation; however, crypt depth remains a strong indicator, regardless of time.Grant Funding Source: Internally funded