bluuebunny/crossref_metadata_2025 huggingface dataset:
Soluble Guanylyl Cyclase and Cutaneous Active Vasodilation During Heat Stress in Humans
Authors: Kellogg Dean Lundt , Zhao Joan Liu , Wu Yubo Beth , Zhao Kun , Johnson John Marshall
Published: June 2021

Nitric oxide(NO) dependent systems typically involve cGMP generation via NO activation of soluble guanylyl cyclase(sGC) as a step in vasodilation. We hypothesized this mechanism participates in cutaneous active vasodilation(AVD) during whole body heat stress(HS). We examined effects of a specific sGC inhibitor, ODQ, on AVD during HS. 3 intradermal microdialysis probes(MD) were inserted into forearm skin in 7 subjects. Skin blood flow was monitored by Laser‐Doppler Flowmetry(LDF). Body temperature was controlled with water‐perfused suits. Blood pressure was monitored by Finapres and cutaneous vascular conductance calculated(CVC=LDF/MAP). The study began with perfusion of Ringer's at all sites, followed by 2%DMSO in Ringer's or 1mM ODQ dissolved in 2%DMSO/Ringer's at 2 separate MD sites. (Preliminary studies showed that 1mMODQ antagonized NO mediated vasodilation by sodium nitroprusside.) Ringer's was continuously perfused at the 3rd control site(CTR). The protocol began with 40 minutes of normothermia followed by 3 minutes of cold stress(CS) after which whole body heating was performed to effect HS and activate AVD. After HS, 58mM SNP was perfused through all MD sites to maximally vasodilate for data normalization.

Results

there were no differences between sites during normothermia. No differences were found between sites in normothermia or CS. There was no significant difference between Ringer's and DMSO sites at the peak of HS on CVC. ODQ tended to attenuate the maximal CVC achieved at the peak of HS(p=0.0536 vs CTR and DMSO). Blockade sGC by ODQ tended to attenuate AVD during HS, these data suggest that sGC activation participates in AVD.
The mechanisms of ethanol‐induced contraction of tracheal smooth muscle
Authors: Jakupaj Muharrem , Sopi Ramadan B , Neziri Burim , Krasniqi Avdyl , Devaja Shqipe , Dreshaj Ismail A
Published: June 2021

We have shown that ethanol induces contraction of pulmonary artery smooth muscle. Therefore, we hypothesized that ethanol induces contractile responses of tracheal smooth muscle and extra cellular Ca2+ plays an important role on these responses. In vitro force measurements were performed in tracheal smooth muscle strips obtained from adult ferrets (n=33). TSM strips were treated with different concentration of ethanol (46 ‐ 322 mM). In another set of experiments strips were incubated in Ca2+ free Krebs ‐Hensleit solution or a Ca2+ channel blocker ‐ nifedipine was used and then treated with ethanol. The involvement of nitric oxide (NO) was studied by inhibition of nitric oxide synthase (NOS) using Nω‐nitro‐L‐arginine methyl ester. The ethanol induced concentration‐dependent contraction of TSM. Prior treatment of tissues with a single dose of ethanol increased the contractile responses of TSM to acetylcholine (p<0.05). Lack of Ca2+ in medium resulted with decrease of contractile force of the TSM likewise Ca2+ channel blocker. Inhibition of NOS significantly increased contractile responses (p<0.001).

These data demonstrate that ethanol induces contraction of TSM and it appears to play a critical role in enhancing cholinergically mediated contractile responses of TSM. Extra cellular Ca2+ plays an important role on these responses and NO release as a relaxant molecule counteracts the effects of ethanol on TSM.
The lectin‐like domain of TNF blunts LLO‐mediated suppression of SGK1 activity and hyperpermeability in human airway H441 cells
Authors: Yang Guang , Xiong Chenling , Hamacher Juerg , Fischer Bernhard , Wendel Albrecht , Chakraborty Trinad , Lucas Rudolf
Published: June 2021

Listeriosis can result in lethal pulmonary permeability edema, with reduced sodium uptake capacity and epithelial/endothelial hyperpermeability. This study investigated the effect of L. monocytogenes' main virulence factor, Listeriolysin O (LLO), on the serum and glucocorticoid dependent kinase 1 (SGK1) and on prostasin, both positive regulators of epithelial sodium channel (ENaC) expression. Moreover, the effects of the TNF‐derived TIP peptide, mimicking its lectin‐like domain, on SGK1 and prostasin expression and permeability in LLO‐treated human H441 cells were investigated. This peptide reduces edema formation in murine models. LLO significantly reduced T256 phosphorylation, required for full activation of SGK1, blunted prostasin expression and reduced expression of the crucial ENaC alpha subunit (Western Blotting). The toxin dose‐dependently induced hyperpermeability in H441 monolayers, as assessed in Electrical Cell Substrate Impedance Sensing. The TIP peptide significantly inhibited hyperpermeability and restored SGK1 activity at 24h in LLO‐treated H441 cells. LLO is thus implicated in permeability edema formation by reducing ENaC expression and epithelial barrier integrity. The TNF‐derived TIP peptide can counteract these effects, indicating its therapeutic potential for the treatment of listeriosis‐related permeability edema.
The comparative study of endogenous growth inhibiting factors of pro‐ and eukaryotic cells
Authors: Dzidziguri Diana , Rukhadze Marina , Bakuradze Ekaterine , Modebadze Irina , Gorozia Ilia , Abashidze Vera
Published: June 2021

Tumour cells are often resistant to signals which inhibit growth of normal cells. Avoiding such control mechanisms may contribute to malignant transformation.

The mammalian normal kidney cells contain the tissue‐specific thermostable protein complex (TPC) suppressing division of normal and transformed epitheliocytes on the basis of our research. The suppressive action of TPC is revealed at the level of genes activity, which results in the reduction of mitotic index of homotypic cells. The low‐molecular active components (10 ‐12 kD) of TPC identified in cells of kidney of phylogenetically distant eukaryotes have analogous characteristics. They do not represent in the human kidney cancer cells.

The goal of the presented work was the comparative study of TPC of pro‐ and eukaryotic cells.

Results

The comparative study has been shown that A. Oxydans as well as animal cells contain TPC, which inhibit the proliferation of homological cells in culture. The inhibiting effect of bacterial TPC is not revealed on the whole animal cells. We have shown that the action of bacterial TPC is apparent only at the level of isolated nuclei.

Conclusion

It is determined that components of bacterial TPC concern family of conservative proteins. In comparison with eukaryotic cells active hydrophilic components of bacterial TPC have a different conformation, which is responsible to its specificity.
Catalytic and specificity determinants in cis‐3‐chloroacrylic acid dehalogenase: pre‐steady state kinetic analysis of active site loop mutants
Authors: Schroeder Gottfried K , Huddleston Jamison P , Robertson Brooklyn A , Johnson Kenneth A , Whitman Christian P
Published: June 2021

cis‐3‐Chloroacrylic acid dehalogenase (cis‐CaaD) is a member of the tautomerase superfamily, with the characteristic α‐β ‐α fold and catalytic Pro‐1. Cg10062, a cis‐CaaD homologue, shares 53% sequence similarity with cis‐CaaD including six key active site residues. However, Cg10062 is a poor cis‐CaaD: it has much lower catalytic efficiency and lacks stereospecificity. This dichotomy indicates that a fully functional cis‐CaaD requires elements beyond the core set. Hence, a pre‐steady state kinetic analysis of cis‐CaaD was performed to define further the characteristics of the tautomerase superfamily, including catalytic and specificity determinants. The results could be used to assign function to other cis‐CaaD homologues. Replacement of a glutamine residue in a flexible loop region near the active site of cis‐CaaD with proline (present in Cg10062) reduced the rate of each kinetically significant step of the catalytic cycle, based on a global fit of all steady and transient state kinetic data. This result holds important implications for the role of loop identity and movement in defining enzyme specificity and function. Supported by NIH GM 65324 and the Welch Foundation F‐1334.
Potential‐dependent permeabilization of the plasma membrane by antitumor polycation peptides
Authors: Lemeshko Victor V.
Published: June 2021

Some polycation antimicrobial KLA peptides demonstrate pro‐apoptotic activity in tumor cells. Antitumor activity of one such KLA peptide, KLAKLAKKLAKLAK, has been strongly enhanced by its conjugation with a cell penetrating hepta‐arginine peptide. It was shown (Law et al., 2006) that cytotoxic activity of the peptide 7r‐kla, D‐form of conjugated peptide, is higher (IC50=3.54 uM) than that of 7R‐KLA (IC50=7.21 uM) and significantly higher than that of kla. Here we studied the capacity of 3.6 uM aforementioned peptides and of 0.36 uM antimicrobial peptide BTM‐P1 (Lemeshko et al., 2005) to permeabilize plasma membrane of red blood cells. Cell swelling was monitored by light dispersion. The membrane potential was monitored by fluorescent probe DioC6(3). The peptides did not permeabilize the plasma membrane with a physiological membrane potential value near ‐10 mV. In contrast, artificially generated potential of approximately ‐180 mV strongly increased the capacity of 7r‐kla and 7R‐KLA, but not of kla, to induce cell swelling that started with a half‐minute lag‐period after a fast drop of the induced membrane potential. The activity of 7r‐kla was almost double of 7R‐KLA, and significantly lower that that of BTM‐P1. Thus, the plasma membrane potential is likely an essential factor for the cell permeabilization by antitumor and antimicrobial polycation peptides. (Supported by Colciencias grant #111840820380).
Crystal structures of Saccharomyces cerevisiae glutamate cysteine ligase reveal mechanistic details of γ‐glutamylcysteine biosynthesis
Authors: Biterova Ekaterina , Barycki Joseph J
Published: June 2021

Saccharomyces cerevisiae glutamate cysteine ligase (ScGCL) catalyzes ATP‐dependent peptide bond formation between the γ‐carboxylate of glutamate and the α‐amino group of cysteine, the first and rate‐limiting step in de novo synthesis of glutathione. Glutathione homeostasis is critically important for maintaining both intracellular redox balance and defense against oxidative or chemical stress. ScGCL was cloned, expressed, and purified to homogeneity. ScGCL crystals were obtained using the sitting‐drop vapor‐diffusion method, belong to the space group P43212, and contain a single monomer in the asymmetric unit. Structures were solved for the enzyme in the presence of glutamate and MgCl2 (2.1 Å R=18.7%, Rfree=22.5%), and also for the complex with ADP, glutamate, cysteine and MgCl2 (2.7 Å R=18.3%, Rfree=24.5%). Examination of the resulting structures provides unprecedented insight into the mechanistic details of class II glutamate cysteine ligases, and clarifies the Mg2+ dependence of the enzymatic reaction. The reported ScGCL structures were used to generate a credible homology model of human γ‐glutamate cysteine ligase. Comparison of the ScGCL structures and the human γ‐glutamate cysteine ligase model suggests that catalytic mechanism employed by ScGCL is conserved across the class II subfamily of γ‐glutamate cysteine ligases.
Adenovirus‐mediated iNOS gene transfer enhances recovery from skin injuries due to sulphur mustard exposure in vitro
Authors: Ishida Hiroshi , Ray Radharaman , Ishhida Keiko , Ray Prabhati
Published: June 2021

Sulfur mustard (SM) is a potent vesicating chemical warfare agent. One of the major specific target organs for SM is the skin, and injuries may take several months to heal and cause substantial functional and cosmetic deficits. There are strong correlations between reduced cutaneous nitric oxide (NO) synthesized by inducible NO synthase (iNOS) levels and impaired wound healing. We reported that SM downregulated iNOS expression to inhibit wound healing and that maintaining of NO level by iNOS gene transfer would be promising candidate therapeutics for SM skin injuries (Ishida et al., 2008). In this study, first we made adenovirus constructs using the AdenoVator(tm) system (Qbiogene) which encode the full length of the open frame of human iNOS cDNA (Ad‐iNOS). In vitro wound was created by scraping a pipetor (with 200‐l tips) in normal human epidermal keratinocytes (NHEK). SM (20 mM) exposure caused a significant reduction of iNOS expression with decreased NO production in NHEK. However, infection of NHEK with Ad‐iNOS 3 h before SM exposure resulted in complete recovery of iNOS expression and NO production. The inhibition of wound healing caused by SM was also recovered by the gene transfer. Mock infection did not show any recovery of iNOS expression, NO production, or wound healing after SM exposure. This work was supported by JSTO‐CBD/DTRA award # 2.T0002_05_WR_C
Identification of an ENU mutant mouse with elevated blood urea nitrogen
Authors: Kung John T
Published: June 2021

With the human genome sequenced, the race is on to understand the functions of the 30,000 or so genes. Ethyl‐nitrosourea (ENU) was used to treat C57BL/6 (B6) male mice, followed by a 3‐generation breeding scheme to generate G3 mice that were screened for immunological phenotypes under recessive genetic control. The primary phenotype of one mutant, P399, was elevated blood urea nitrogen. Pathology analysis of major organs of affected mice revealed hydronephrosis in the kidney. Recessive mode of inheritance was confirmed by mating an affected G3 male to wildtype B6 females to generate F2 offspring. No affected phenotype was found in F1 mice and approximately 1 in 4 F2 mice were pheno‐deviants, consistent with monogenic control. Affected G3 mice were outcrossed to generated F2 offspring and the affected F2 mice were subjected to linkage analysis by haplotype interval mapping (Neuhaus and Beier, 1998. Mammalian Genome 9, 150‐154). The mutant gene was found to be linked to chromosome 1. The P‐399 mutant may be used as a model to study the molecular mechanism of kidney disease and to establish ways to treat, prevent, or delay the onset of such diseases.
Pax‐5B predisposes B lymphocytes to a survival pathway
Authors: Bedard Melanie , O'Brien Jeannick , Robichaud Gilles A
Published: June 2021

The Pax‐5 gene codes for a powerful transcription factor that plays a key role in the development and maturation of B cells as well as in oncogenic processes. Under the control of two alternative promoters, Pax‐5 can simultaneously generate two different variant proteins (Pax‐5A and Pax‐5B) which are both important in the modulation of fundamental biological processes such as cellular survival and apoptosis. However, few studies have scrutinized the specific function between Pax‐5 expressed variants in B lymphocytes. We have developed a Pax‐5B suppressed cell model system in B cells based on ribozyme technology. Through the use of this study model, we set out to elucidate the specific roles of the Pax‐5B variant in B lymphocyte activity and oncogenesis. Our results show that Pax‐5B‐deficient cells are more susceptible to undergo programmed cell death. We observed that Pax‐5B down‐regulated pro‐apoptotic genes (Bax, p53, PD‐1) while suppressing anti‐apoptotic element (Bcl‐2). This study brings insight to a better understand of B cell processes and cancer pathogenesis. These findings also help elucidate signaling cascades involved in Pax‐5‐associated oncogenesis and potentially support the discovery of new therapeutic targets.
Kr̈¹ppel‐like factor 4 inhibits RAR α‐mediated signaling transduction in vascular smooth muscle cells
Authors: Zheng Bin , Han Mei , Meng Fang , Zhang Xin‐hua , He Ming , Miao Sui‐bing , Zhao Xin‐ming , Wen Jin‐kun
Published: June 2021

Proliferation inhibition of vascular smooth muscle cells (VSMCs) is governed by the activity of a transcription factor network. Both the Kr¨ppel‐like factor family member Klf4 and retinoic acid receptor (RAR α) are components of such a network. However, the relationship between Klf4 and RAR α in mediating proliferation‐inhibitory effects in VSMCs remains unknown. Here, we investigated the mechanisms whereby Klf4 mediates the feedback loop of the growth‐inhibitory effects of the RAR α. We used chromatin immunoprecipitation to show that Klf4 binds to the 5¡ä regulatory region of RARα, down‐regulates RAR α expression, and specifically inhibits RARα ‐mediated PI3K‐ERK signaling. We also showed that regulation of growth inhibition by Klf4 is dependent on RARα‐PI3K‐ERK signaling since the growth‐inhibitory response to Klf4 is blocked by PI3K‐ERK inhibition. Further, we demonstrated that Klf4 is itself regulated by the PI3K pathway. Thus, Klf4 regulates RARα‐mediated PI3K‐ERK signaling and is itself downstream of PI3K‐ERK signaling. This provides a novel mechanism for signal amplification or suppression and for the control of growth‐inhibitory effects in VSMCs. Moreover, the results of this study suggest that Klf4 is one of the key mediators of retinoid actions in VSMCs.
Eliminating leptin signals to somatotropes reduces GH and fertility and causes obesity in adults
Authors: Childs Gwen V , Akhter Noor , Haney Anessa , Brodrick Zachary , Gaddy Dana , Suva Larry , Crane Christopher , Benes Helen , Charlesworth Amanda , Kineman Rhonda , Luque Raul , Chua Streamson
Published: June 2021

Leptin restores growth hormone (GH) in leptin‐deficient animals, suggesting a role in somatotrope maintenance. To determine leptin's importance to somatotropes, we ablated the leptin receptor (LEPR) selectively using targeted Cre‐recombinase in somatotropes of mice bearing two floxed alleles of LEPR exon 17, thereby removing the JAK binding site of LEPR‐b. We detected no early or extrapituitary expression of Cre‐Recombinase and 3 generations showed >95% viability. In adult males or females, the mutation reduced serum GH by 50‐84% and reduced % of pituitary cells bearing LEPR‐b or GH. For example, pituitary cells with LEPR‐b in males declined from 37 ± 1% (controls) to 20 ± 2% (heterozygotes) and 11 ± 1% (homozygotes) and GH cells in males were reduced from 26 ± 2% (controls) to 12 ± 1% or 7 ± 1% in F2 or F3 generation homozygotes, respectively. In spite of reduced GH, mutant mice grew normally. However, a 70% reduction in corpora lutea in F2 homozygotes correlated with a significant reduction in litter size. By 3‐4.5 months of age, homozygote males showed significant weight gains (30% over controls) and a 1.8‐fold increase in percent body fat by DEXA analysis. Females showed these changes by 6 months. Direct leptin signaling to somatotropes is thus important especially in functions related to maintaining GH, fertility and body composition. Supported by DK26687 (SC), and core facilities funded by P20 RR020146 and P30 NS047546.
Evaluation of nitric oxide production in cultured pulmonary myofibroblasts
Authors: Sharma Bethel , Clouse Margaret , Rice Nancy A.
Published: June 2021

Idiopathic pulmonary fibrosis is a destructive disease that stems from collagen buildup in the lungs due to the presence of excess, and/or overactive, myofibroblast cells. Nitric oxide (NO) has been implicated as a key modulator of myofibroblast growth and proliferation. In order to better understand the mechanism by which NO contributes to myofibroblast pathogenesis, a robust functional assay to monitor NO production at submicromolar levels has been developed. Myofibroblasts, isolated from rat lungs, were cultured under normal and pseudo‐pathological conditions for 24 h prior to treatment (10 mM PBS pH 7.4, 100 uM CaCl2, 1 mM L‐arginine, and 1 uM A23187 selected NO synthase inhibitors). Nitric oxide levels were detected in solution amperometrically, using a NO specific electrode. NO levels measured for basal and treated cells were amplified by a nitrite conversion step using a metal‐based catalyst. Treated samples showed a decrease in measured NO as compared to basal levels. The low levels of NO produced by myofibroblasts were detectable using the electrode based system, and the amount of accumulated NO detected was enhanced by the addition of a nitrate reduction step. This system will be used to elucidate additional factors contributing to modulation of NO levels in myofibroblasts. Support for this research has been provided by the NIH (NAR): R15HL087185, P20RR16481.
Peer teachers introducing anatomy to first year medical students
Authors: Kiene Jason , Lasek Ray , Wish‐Baratz Susanne , Freeman Barbara
Published: June 2021

Systems approaches to medical education have changed the approach to anatomy from a concentrated "course" to a longitudinal, integrated theme in many medical school curricula. Thus, students may be forced to learn anatomy regionally without a sense of how different body systems are integrated. Furthermore, teaching by senior students has been found to be an effective educational method and can augment faculty resources in a small‐group curriculum. These issues led to our study question: Can a 10 hour introductory anatomy course taught solely by 2nd year medical students in a small‐group format improve the preparation of 1st year medical students for the demands of a systems‐based anatomy course?

We had four goals:

1) Provide a basic framework for the anatomy of major body systems

2) Develop teaching and learning modules that show the relationship between anatomic structures, physical diagnosis and radiology

3) Utilize peer‐teaching

4) Promote interest in anatomy

Students finished 90% of each session. The average score on the cumulative quiz was 93%. Surveys indicated extremely high satisfaction with the course, overwhelmingly positive feedback about the peer teachers, and good pre‐class preparation by students. We saw no statistical difference in scores on the subsequent curricular anatomy assessments. Overall, goals 1‐4 were successfully met. However, incremental knowledge was not reflected in test scores.
Proliferation studies in the chick ear‐forming region using EdU labeling
Authors: Chapman Susan C.
Published: June 2021

Cell proliferation studies are an important experimental tool, which commonly include PCNA and phospho‐histone H3 antibodies again proteins present in mitotic cells, and the thymidine analogues tritiated thymidine and BrdU, which label cells during S‐phase. Both the latter methods have significant drawbacks, with low sensitivity in the case of tritiated thymidine and a denaturation step during BrdU detection that destroys most cellular epitopes, requiring careful optimization. The BrdU antibody is also large and tissue penetration can be difficult, moreover multiplex antibody detection is compromised due to the denaturation step. EdU is a closely chemically related molecule to BrdU. Detection is achieved by a copper catalyzed reaction requiring a small fluorescently conjugated azide. We have developed a tissue labeling technique in chick embryos using EdU. Following EdU chemistry to detect proliferating cells the tissue can undergo immunolabeling. We demonstrate fluorescent EdU chemistry followed by Tuj1 antibody staining resulting in multiplex fluorescently labeled tissues. To understand the role of proliferation in ear formation we are undertaking proliferation studies in the ear‐forming region of early chick embryos.
Specific Silencing of Janus Kinases on Proliferating T Lymphocytes
Authors: Gómez‐Valadés Alicia , Llamas Maria , Gómez‐Casajús Lluís , Mascaró Cristina
Published: June 2021

Jak3 is the only janus kinase among the four family members (Jak1. Jak2, Jak3, and Tyk2) which is predominantly expressed in haematopoietic linage. Small molecule inhibitors of the Jak's are being actively studied for immunosuppressive therapies. Nevertheless, they have not shown a selective pattern versus the different family members and implications over the therapeutic efficiency of a JAK3‐specific antagonist remain unclear.

In this study we aim to investigate the effects of specific Jak3 inhibition using the powerful and specific iRNA technology. Specific sequences against human Jak1 and Jak3 were designed and successfully transfected into primary human T lymphocytes. Upon siRNA treatment, specific and stable silencing was observed at the RNA and protein level. After selective Jak abrogation, IL‐2‐induced proliferation was potently inhibited, and cell death was clearly induced. These effects on cell viability were dose dependent, in correlation with silencing effect. Nevertheless, we never observed an additive effect over the viability when Jak1 and Jak3 (whose heterodimerization is required to transduce IL‐2 signalling) were co‐silenced. These data indicate that a selective Jak3 inhibitor can, per se, modulate IL‐2 signalling, reinforcing the idea that a Jak3 selective antagonist could report therapeutic benefits as immunosuppressant.
NK cell function is depressed in Gulf War Illness
Authors: Whistler Toni , Fletcher Mary Ann , Lonergan William , Klimas Nancy G
Published: June 2021

Gulf War Illness remains a serious health consequence for veterans deployed during the first Gulf War. Our understanding of the health consequences remains inadequate, and this is of concern with another deployment occurring now. Chronic immune cell dysfunctions have been reported, although the literature is not uniform.

We used an exercise stress paradigm to determine differences in immune measures and gene expression profiles between the baseline, immediately after exercise and 4 hours later, in GWI subjects compared to sedentary veteran controls. Repeated‐measures ANOVA showed that there were statistically significant differences for NK cytotoxicity and NK cell subsets between cases and controls. Linear regression analysis correlating NK cell numbers to expression profiles showed high correlation of genes relating to NK cell function. We found the intracellular perforin levels trended lower and showed a flatter profile in GWI cases than controls, as did the expression levels of the perforin gene, PRF1.

GWI patients demonstrated impaired immune function, involving Th2 and proinflammatory cytokines, cytotoxic NK and T cells, and dysregulated mediators of the stress response including salivary cortisol, compared to control subjects. An important observation was that the exercise challenge augments these differences, with the most significant effects observed immediately after the stressor.
Vascular Cell Adhesion Molecule (VCAM‐1) predicts Atrial Fibrillation after On‐Pump Heart Surgery
Authors: Lavandero Sergio , Verdejo Hugo , Garcia Lorena , Becerra Elia , Roldan Juan , Chiong Mario , Mellado Rosemarie , Zalaquet Ricardo , Braun Sandra , Corbalan Ramon
Published: June 2021

Post‐Operative Atrial Fibrillation (POAF) occurs in 30% of patients after on‐pump heart surgery (OPHS). POAF is associated to elevated inflammatory markers; whether this reflects systemic inflammation or local atrial changes is unknown.

Methods

70 patients in sinus rhythm submitted to elective OPHS were included. Systemic inflammatory and oxidative stress markers were measured at baseline and 72 h after surgery. During the procedure, a sample of right atrial appendage was obtained. EKG was monitored for 72 h after surgery for event adjudication.

Results

37% of the patients developed POAF. Systemic inflammatory and oxidative stress markers did not differ between groups. Baseline serum VCAM‐1 was higher in patients who developed POAF and remained an independent predictor for POAF (OR 5.06, p = 0.02) after adjustment. No association was observed between serum VCAM‐1 and VCAM‐1 expression levels in right atrial appendage.

Conclusion

In patients undergoing OPHS, elevated VCAM‐1 serum levels predict a higher risk for POAF. This elevation is not related to increased expression of adhesion molecules in right atrial, suggesting that systemic inflammation rather than local changes pre‐exist in patients who develop the arrhythmia.

FONDECYT 1070641, DI‐06‐09‐2, FONDAP 15010006
Role of the NF‐kB pathway in rats subjected to moderate hemorrhage
Authors: Doursout Marie‐Francoise Joelle , Liang Yang Yan , Uray Karen S. , Pati Shibani , Matijevic Nena , Holcomb John B.
Published: June 2021

Mechanisms by which hemorrhagic shock leads to hemodynamic disturbances are not fully understood. Nuclear factor kB (NF‐kB) is a nuclear transcription factor that regulates expression of genes critical for the regulation of diseases. We hypothesize that NF‐kB is responsible for the hemodynamic changes associated with hemorrhagic shock in conscious rats. Under isoflurane, catheters were implanted into the aorta to record mean blood pressure (MAP) and heart rate (HR) and in the femoral vein for drug administrations. Cardiac output (CO) was recorded through Doppler flow probe. A blood volume of 2.0 ml/100 g of body weight was withdrawn over a 5‐min to induce moderate hemorrhage. Group 1 (n=6) was subjected to moderate hemorrhage only. Group 2 (n=5) was hemorrhaged in the presence of TPCK, an inhibitor of NF‐kB at 10 mg/kg sc. Our data show that hemorrhagic shock induced decreases in MAP by 30%, HR by 40% whereas CO remained unchanged. Moderate hemorrhage induced significant systemic vasoconstriction. As compared to hemorrhaged animals, TPCK restored MAP to baseline. Furthermore, moderate hemorrhage‐induced systemic vasoconstriction was significantly reduced in the presence of TPCK. Our data suggest that NF‐kB plays a major role in the hemodynamic changes induced by moderate hemorrhage. Development of NF‐kB inhibitors that will be tissue‐specific and/or isoform‐specific as therapeutic agents need to be pursued.
A case‐study of fucoxanthin uptake kinetics
Authors: Craft Neal E. , Arredondo‐Vega Francisco X.
Published: June 2021

Fucoxanthin (FX), a carotenoid in seaweed, has been reported to increase lipid oxidation in adipose tissue leading to weight loss. Little is known about FX kinetics and biochemical activity. We initiated a case study examining the uptake of FX into the blood of an adult male.

Objective

To monitor FX and metabolite concentrations in serum following FX consumption.

Methods

Blood was collected at 0, 4, 8, 24, 48, 72, 96 hrs. FX was consumed as softgels post blood draw (0 hr) and on days 1‐4. On day 0, 11mg of trans‐FX was consumed and 6.6mg on each successive day. Serum was harvested each day of blood collection and frozen. On day 4, blood samples were analyzed by HPLC using a C30 gradient separation with DAD. Based upon the results, no additional blood was collected.

Results

All of the major carotenoids reported in human blood plus FX and a metabolite, Fucoxanthinol (FXOH), were measured. FXOH was observed in the blood at 4hr (2.6 ng/mL) and peaked at 8hr (9.6 ng/mL) and returned to 2.2 ng/mL by 24hr after the initial FX consumption. FXOH was measured in the serum on each day (0.8‐1.1 ng/mL) but did not accumulate in the blood with each day of consumption. Blood and urine were also tested for conjugates of FX or FXOH.

Discussion

FX was not measurable in the blood samples. FXOH appearance and decline in serum was more rapid than reported for less polar carotenoids and it does not appear to accumulate in its endogenous form in this tissue.
Modulation of Endothelial ADAMTS‐13 Expression and Activity
Authors: Wilson Emily
Published: June 2021

ADAMTS‐13 (a member of the A Disintegrin and Metalloprotease with Thrombospondin type motif family) functions to cleave unusually large (UL) of von Willebrand factor (VWF) that are secreted from activated endothelial cells. Cleavage of VWF by ADAMTS‐13 converts the UL forms to smaller forms that are hemostatically but not pro‐thrombotic. ADAMTS‐13 deficiency is associated with systemic thrombosis , typically thrombotic thrombocytopenic purpura (TTP).. Recent studies showed that endothelial cells expressed ADAMTS‐13 constitutively and that this may also be an important source of ADAMTS‐13. We hypothesized that local regulation of expression levels and activity of ADAMTS‐13 may be an important determinant in platelet adhesion in various other diseases including atherosclerosis, deep vein thrombosis and shock. Specifically, we hypothesized that expression and or activity of ADAMTS‐13 might be modulated in a shear stress‐dependent manner. NO production is associated with regions of high shear stress and inhibits platelet adhesion and thrombosis. We treated human umbilical vein endothelial cells (HUVECs) an NO resulting in a 30‐40% increase in both mRNA and protein Hoever, the activity of secreted ADAMTS‐13 increased by 3 fold as determined using a fluorescent peptide substrate. Treatment with Tumor necrosis factor‐alpha (TNF) casused a marked decrease in protein levels (50%) and activity (45%). These results support the hypothesis that local changes in ADAMTS‐13 expression and activity may contribute to regions of the vasculature that are either pro‐ or anti‐thrombotic and thus may contribute localization of specific vascular diseases. This work was supported by the Mary R. Gibson Foundation.
Improved myogenic differentiation and myoblast fusion under physiological amino acid concentrations
Authors: Haegens Astrid , Schols Annemie M. , van Essen Anon L.M. , van Loon Luc J.C. , Langen Ramon C.
Published: June 2021

Myoblast cell lines have been applied to model myogenesis in vitro. Muscle growth can be modulated by altering insulin, IGF‐I, as well as amino acids (AA) levels. However, little attention has been paid to the fact that most culture media contain supra‐physiological AA levels. This raises the question whether such conditions are suitable for AA related research questions and whether the data are relevant to in vivo experiments. The aim of this study was to determine if myogenesis of C2C12 myoblasts differed in the presence of physiological AA levels compared to supra‐physiological levels. Myoblasts were grown in DMEM with low glucose and 10% FBS. DMEM was diluted with HBSS supplemented with NaHCO3 to yield culture media of similar composition containing 5‐100% of AA levels in unmodified DMEM. Physiological levels of AA were reached at ~15% of unmodified medium. Differentiation was induced by culturing the cells in DMEM with 1% FBS and decreasing levels of AA. Myogenesis was assessed 3 and 5 days after differentiation initiation. Myoblast fusion, creatine kinase activity and myosin heavy chain‐fast were increased in cells cultured in DMEM containing physiological levels of AA compared to unmodified medium. These findings show that supra‐physiological AA levels result in sub‐optimal differentiation, emphasizing the use of physiological AA levels in muscle cell culture for more meaningful in vivo extrapolation of data.
Perceived Hunger in Young Adults Susceptible to External and Emotional Eating
Authors: Schembre Susan M , Kresge Daniel L , Melanson Kathleen J , Greene Geoffrey W
Published: June 2021

The study objectives were to determine if high versus low emotional and situational eaters (High ES vs Low ES) perceive hunger (VAS‐H) differently before and after a test meal and if observed differences correspond with the appetite‐related plasma biomarkers total ghrelin (TG) and insulin (INS). Participants (N=54) were healthy, 18 to 27 year old males and females (BMI=23.5±3.7 kg/m2). ES was calculated by summing two corresponding subscale scores of the Three Factor Eating Questionnaire disinhibition scale. VAS‐H, measured by a visual analogue scale, and blood samples were collected following a 12‐hour fast and 30‐minutes after a standardized test meal. TG was assessed by radioimmunoassay and INS was assessed by ELISA. High ES versus Low ES scores were determined by median split. T‐tests and ANCOVA were performed to test for group differences. High ES young adults had greater fasting VAS‐H (54.5±24.2 mm vs 26.9±38.3 mm, p=0.02) without corresponding differences in fasting TG (P=0.88) or INS (p=0.32). Post prandial decreases in VAS‐H (p=0.43) and TG (p=0.27) and increases in INS (p=0.82) were not different between groups. High ES young adults appear to perceive greater fasting VAS‐H without corresponding differences in TG or INS. Other descriptive characteristics of High ES vs Low ES young adults will be explored. Additional research is needed to determine the impact of ES on meal frequency and caloric intake.
Water‐soluble extract of Cauliflower mushroom shows anti‐obesity effects in high fat diet‐induced obese mice
Authors: Lee Mi AE , Chon Jeong Woo , Park Jin Kyung , Kang Myung‐Hee , Park Yoo Kyoung
Published: June 2021

Cauliflower mushroom (CM) has been recently reported to have immune boosting effect in animals and humans. We investigated the anti‐obesity effect of water‐soluble extract of Cauliflower mushroom in diet‐induced obese (DIO) mice. Mice were induced by a high fat diet (fat 45% in total kcal) for 10 weeks. Experimental groups were treated with two different dosage of Cauliflower mushroom extracts (100mg/kg/day (LCM) and 300mg/kg/day (HCM)) by gavages for 10 weeks, respectively. Body weight gain, serum and hepatic lipid levels were measured after scarificed. The body weight gain of the mice fed CM was significantly reduced (11.87% in LCM, 14.55% in HCM) compared with the control group. Additionally, serum level of total cholesterol (32.21% in LCM, 24.67% in HCM), triglyceride (13.57% in LCM, 19.46% in HCM), and glucose (28.85% in LCM, 25.82% in HCM) in mice fed CM were significantly decreased, respectively. Hepatic triglyceride in mice fed CM was lower(17.76 %, 22.77%) than control group and total cholesterol level were also lower in CM(27.57%, 13.64%)group than control group. These results demonstrate that the water extract of CM, regardliess of the treatment dose,improve serum and hepatic lipids and body weight reduction in DIO mice. The showed similar results in the low dose(LCM) and high dose(HCM). Therefore, our results suggest that in mice fed low dose also cooperative effects appeared.
Short term changes in plasma phenylalanine status and cognitive processing speed in adolescent and adult females with phenylketonuria (PKU)
Authors: Yi Sarah , Kable Julie A. , Singh Rani H.
Published: June 2021

Even with early and continuous diet therapy, subtle neuropsychological deficits exist in phenylketonuria (PKU). To clarify the relationship between compliance and processing speed, this study examines the relationship between short‐term changes in plasma phenylalanine (Phe) concentration and cognitive processing speed. Data were collected from twenty females with PKU (ages 12‐47 years) attending a summer camp intervention designed in part to reduce plasma Phe. Pre‐ and post‐intervention fasting plasma Phe was assessed using ion‐exchange chromatography. Pre‐ and post‐intervention processing speed was assessed in group format by Woodcock‐Johnson III timed tests of decision speed and pair cancellation. As expected, mean plasma Phe and processing speed scores significantly improved (p<0.001) and pair cancellation negatively correlated with change in plasma Phe controlling for verbal ability (r=‐0.627, p=0.004). Changes in decision speed and plasma Phe, however, were unrelated. Pair cancellation may be more sensitive to improved Phe control due to the task's reliance on attention and concentration. Short‐term improved compliance may be associated with concurrent improved processing speed. Supported in part by PHS Grant M01 RR00039 from the General Clinical Research Center program, National Institutes of Health, National Center for Research Resources.
Physicians and nurses use and recommend dietary supplements: report of a survey
Authors: Dickinson Annette , Boyon Nicolas , Shao Andrew
Published: June 2021

There have been relatively few surveys on the prevalence of dietary supplement use among physicians and nurses, or the extent to which they recommend dietary supplements to their patients. An online survey was administered in October 2007 to 900 physicians and 277 nurses by Ipsos Public Affairs for the Council for Responsible Nutrition (CRN), a trade association representing the dietary supplement industry. The "Life…supplemented" Healthcare Professionals Impact Study (HCP Impact Study) found that 72% of physicians and 89% of nurses used dietary supplements regularly, occasionally, or seasonally. Regular use of dietary supplements was reported by 51% of physicians and 59% of nurses. The most common reason given for using dietary supplements was for overall health and wellness (40% of physicians and 48% of nurses), but more than two‐thirds cited more than one reason for using the products. When asked whether they "ever recommend dietary supplements" to their patients, 79% of physicians and 82% of nurses said they did. Physicians and nurses are as likely as the general public to use dietary supplements, and many recommend supplements to their patients. Funded by CRN.
The relationship of serum phospholipids fatty acid composition with metabolic syndrome and cardiovascular disease risk in Korean adults
Authors: Kim Bumsik , Park JY , Kim JY , Paik JK , Ordovas JM , Lee JH
Published: June 2021

This study aimed to determine whether fatty acid (FA) composition in serum phospholipids affects metabolic syndrome (MetS) and cardiovascular disease (CVD) risk in Korean adults aged at least 20 years. 722 adults were recruited. 116 adults of them met MS criteria (American Heart Association/National Heart, Lung, and Blood Institute, 2005). To examine CVD risk, we measured PWV by an automatic waveform analyzer (model VP‐1000; Nippon Colin Ltd., Komaki, Japan). Serum phospholipids FAs were measured by gas‐liquid chromatography. Compared with subjects without MetS, those with MetS had higher 18:1 n9, 20:3 n6 and lower 18:2 n6, 20:0, 22:1, 24:0 (p<0.05). PWV was significantly higher in MetS than normal adults (p<0.01). PWV was associated positively with 16:0, 20:3 n6, 22:0, Saturated FA (p<0.05). In contrast, it was associated negatively with 12:0, 18:2 n6, 20:0, PUFA, n6 FA (p<0.05). These results show that MetS may increase CVD risk by influencing FA metabolism, especially, increase of 20:3 n6 and decrease of 18:2 n6 and 20:0.
Consistent ketogenic therapy ratio does not mean consistent fatty acid intake
Authors: Umakanthan Sinthana , Borum Peggy R.
Published: June 2021

Ketogenic Therapy (KT) is a high‐fat, low‐carbohydrate, adequate‐protein diet administered to patients with intractable epilepsy. KT is defined by the KT ratio which is grams of fat: grams of protein + grams of carbohydrate. Patients with similar clinical characteristics often respond differently to the same KT ratio. One factor may be that the therapy administrated differs among patients. Due to the nature of KT, our primary focus was fatty acid intake. Published reports suggest fatty acids of different chain length with different patterns of saturation/desaturation variably affect seizures. Since it is assumed that KT administered via feeding tube is more consistent in composition than KT administered orally with table foods, diet diaries were collected for 6 tube‐fed pediatric patients receiving KT at a ratio of 3.5:1. Dietary intake was analyzed using the Nutrition Data System for Research program. Patients had been receiving KT from less than 1 year to more than 9 years when prescribed the 3.5:1 ratio, and no patient received a single product as their sole source of food. Fatty acid intake varied from 3 to 9 fold in terms of saturation/desaturation pattern and varied even more with chain length. Trans fatty acid intake ranged from 0 to 11% of total fat. KT ratio does not adequately assess KT potency or the parameters of KT which may impact patient response.
Physiologic assessment of a new mouse model of abnormal cardiac conductance: Chronic electrocardiogram, heart rate, temperature, and activity via telemetry
Authors: Grenwis Jessica E. , Huetteman Daniel A. , Svenson Karen L.
Published: June 2021

Miniature telemetry devices have enabled smaller animals to be implanted for monitoring cardiovascular (CV) parameters. Advances in the derivation and screening of mouse models of CV disorders, including n‐ethyl‐n‐nitrosourea (ENU)‐induced single gene mutants, have enabled identification and isolation of key elements leading to human CV disease. This study demonstrates that telemetry is an accurate and effective method for assessing mouse mutants with aberrant electrocardiograms (ECG). A recently characterized ENU mutant with prolonged P‐R interval and long QT was instrumented with a new ETA‐F10 transmitter (DSI, St. Paul, MN); control animals (C57BL6/J) were also implanted. The transmitter is implanted via midline laparotomy and the ECG sensing leads are placed in a lead II configuration. Experimental and control groups were continuously monitored to obtain ECG, heart rate, temperature, and activity data. Results show that these data can be easily and accurately sampled in unrestrained mice and that strains carrying genetic mutations affecting CV function are readily distinguishable from control animals. This approach adds important in‐depth characterization of mouse CV disease models without complicating the interpretation of outcome with anesthesia or restraint. DSI provided lab space and monitoring equipment; JAX provided mice with support from NHLBI Program for Genomic Application HL66611.
Association between surrogate indicators of obesity and circulating concentrations of cancer associated micronutrients: Racial differences
Authors: Badiga Suguna , Rahman Nuzhat , Brill Ilene , Piyathilake Chandrika
Published: June 2021

Even though race, obesity and micronutrients have been shown to modify cancer risk, there are no reports on the racial differences in the association between obesity and circulating concentrations of cancer protective micronutrients. The objective of our study was to determine the association between degree of obesity as indicated by body mass index (BMI), waist circumference (WC) and % body fat (BF) and circulating concentrations of micronutrients (folate, vitamin B12, A, E and C, and total carotenoids) by race in 273 women (187 African Americans (AA) and 86 Caucasian Americans (CA) at risk for developing cervical cancer (CC). All women were categorized based on the WHO classification of BMI (normal weight <18.5, 18.5‐24.9, overweight 25‐29.9, and obese =30 kg/m2), WC tertiles (>87, >106 cm) and % BF tertiles(>33.1, >43.7). Multiple regression analyses were used to analyze the relationship between BMI, WC, and % BF and log transformed circulating concentrations of micronutrients by race after controlling for age, education, current smoking status, parity, use of hormone contraceptives, total dietary calories, healthy eating index (HEI) score and physical activity. While a positive association was observed between gamma‐tocopherol and BMI, a negative association was observed between vitamin B12 and BMI (P<0.05). Similar trends were observed with other indicators of obesity. These main associations were not significant by race. Future studies will focus on the relevance of these associations on CC risk.
Rho‐kinase inhibition abolishes the vasoconstrictor response to hypoxia in the infant piglet pulmonary arterial circulation
Authors: Balasundaram Naveen , Chowdhary Paraag , Titus James , Jagannath Anand , Carillo Kathleen , Myers Jeff L
Published: June 2021

We examined the effects of the rho‐kinase inhibitor fasudil on the regional response of the infant pulmonary arterial (PA) circulation to hypoxia. 15 two week old piglets were instrumented to record PA pressure (PAP). Control animals (n=7) were exposed to hypoxia (FiO2 = 0.05). Treated animals (n=8) were infused with fasudil (5mg/Kg) before and during hypoxia. Input mean impedance (Zm, reflecting distal arteriolar vasoconstriction) and characteristic impedance (Zo, reflecting proximal arteriolar opposition to flow) were calculated.

Hypoxia caused a potent vasoconstrictor response distally (increased Zm). Zo was unchanged indicating no alteration of the proximal circulation. Pre‐treatment with fasudil completely abolished the increase in Zm and PAP indicating that the distal vasoconstrictor response is rho‐kinase dependent. Rho‐kinase inhibitors may be an effective therapy for hypoxic pulmonary hypertension in infants, but may be limited by its effect on systemic blood pressure. Funded by Dept. of Surgery, Mass. Gen. Hosp.