bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detection of Autologous Blood Transfusion by Metabolomics
Authors: Bejder Jacob , Gürdeniz Gözde , Cuparencu Catalina , Hall Frederikke , Gybel-Brask Mikkel , Andersen Andreas Breenfeldt , Dragsted Lars Ove , Secher Niels Henry , Johansson Pär Ingemar , Nordsborg Nikolai Baastrup 
Published: April 2020

Autologous blood transfusion (ABT) is illegal for competing athletes but misuse remains difficult to detect. Thus, the development of novel and sensitive methods is warranted. In this study, we explored whether ABT causes a shift of the urine metabolome. The hypothesis was that an untargeted metabolomics analysis of urine is able to identify novel biomarkers sensitive to ABT.In a randomized, double‐blinded, placebo‐controlled cross over design (3 month wash‐out), twelve trained males donated 900 ml blood or were sham phlebotomized. Four weeks later, a transfusion of the stored red blood cells or a sham transfusion was completed. Urine was collected before phlebotomy and 2 h, 1, 2, 3, 5 and 10 days after transfusion and analyzed by UPLC‐QTOF‐MS.Models of unique metabolites reflecting ABT was derived by partial least squares regression discriminant analysis. The strongest model appeared 2 h after transfusion (misclassification error: 6.3%, specificity: 98.8%). The remaining time points provided misclassification errors from ~20–50% with specificities of ~50–80%. Metabolite identification revealed secondary di‐2‐ethylhexyl phtalate metabolites as the strongest biomarkers for detection.In conclusion, untargeted metabolomics of urine identified plasticizers as the strongest metabolites for ABT detection. Future research should validate the proposed models.Support or Funding InformationThe study was funded by Partnership for Clean Competition
Increased Lipopolysaccharide‐Induced Hypothermia in Neurogenic Hypertension is caused by Reduced Hypothalamic PGE2 Production and Increased Heat Loss
Authors: Amorim Mateus R. , Moreira Diego A. , Santos Bruna M. , Ferrari Gustavo D. , Nogueira Jonatas E. , de Deus Júnia L. , Alberici Luciane C. , Branco Luiz G.S. 
Published: April 2020

Brain‐mediated thermoregulatory changes in systemic inflammation (SI) induced by lipopolysaccharide (LPS) at a septic‐like model are characterized by hypothermia followed by fever which are associated with inadequate tissue oxygenation, multiple organs dysfunctions, and death. Hypertension is a prevalent chronic disease characterized by autonomic‐induced elevated and sustained blood pressure levels and spontaneously hypertensive rats (SHR) also have abnormal body core temperature (Tb) regulation and metabolic adjustments, by unknown mechanisms. The rationale of the present study was to find out the mechanisms involved in the thermoregulatory changes observed during SI in SHR. We combined Tb and skin temperature (Tsk) analysis, assess prostaglandin (PG) E2 levels in the anteroventral region of the hypothalamus (AVPO), indirect calorimetry, cardiovascular recordings, assays of inflammatory markers and evaluation of oxidative stress status in male Wistar and SHR that receive intravenous administration of LPS (1.5 mg.kg−1) or saline (CEUA #2017.1.585.58.9). As expected, LPS induced hypothermia followed by fever in Wistar whereas in SHR increased hypothermia and no fever were observed. These changes were associated with an increased Tsk in SHR in relation to Wistar (P < 0.05). Oxygen consumption and carbon dioxide production were significantly and similarly reduced in both SHR and Wistar rats during SI (P < 0.05). Interestingly, we measured increased AVPO PGE2 levels in Wistar during SI (P < 0.05), but not in SHR. LPS‐induced drop in MAP was significantly higher in SHR than in Wistar rats. Besides, LPS‐induced plasma and brain cytokines surges were blunted whereas oxidative stress was higher in SHR (P < 0.05). The present data are consistent with the notion that in SHR LPS‐induced SI leads to thermoregulatory changes mediated by the thermo effector mechanisms in the skin but not in energy expenditure and these events are associated with reduced hypothalamic PGE2.Support or Funding InformationFAPESP, CAPES and CNPq
CYTOTOXIC ACTIVITIES OF SELECTED MOLLUSC SHELLS ALONG THE EASTERN CAPE COAST IN SOUTH AFRICA
Authors: Nakin Motebang Dominic Vincent , Saibu Gbemisola Morounke , Oyedeji Adebola Omowunmi , Piya Viwe , Meyer Mervin 
Published: April 2020

IntroductionThe application of some natural products from mollusc shells has been known for centuries. Secondary metabolites produced in marine organisms could be the source of bioactive substance and used for cosmetic purposes. Cosmetic potential of mollusc shells has become a critical scientific concern to most researchers around the world. The aim of the present study was to evaluate the cytotoxicity activity of some selected mollusc shells of mussels (Perna perna), oysters (Sacostrea cuculata) and limpets (scutellastra longicosta) collected from Port St Johns in the Eastern Cape coast of South Africa.Materials and MethodsHuman keratinocyte e (HaCaT) and human fibroblast (KMST‐6) cell lines were treated with various concentrations (0.0312, 0.0625, 0.125, 0.25, 0.5, 1, 2.5, 5, 7.5 and 10 mg/ml) of Mollusc shells for 24 hours after which cell proliferation was measured by MTT assay.ResultsThe IC50 values could not be obtained for the KMST‐6 treated cells. However, for HaCaT treated cells, there was significantly (p < 0.05) moderate cytotoxicity activity at a concentration range of 0.312‐0.02 mg/ml for all the five extracts.Discussion and ConclusionSince the IC50 values could not be obtained for the non‐cancerous (KMST‐6) that implies the safety of the extracts for cosmetic purposes. The moderate cytotoxicity obtained from the cell treated with Human keratinocyte (HaCaT) cell line also make them appropriate candidate for further studies and identification of their bioactive principles. These extracts could also be used as an alternative source for treatment of fungal infections.
Can Interleukin‐8 Alone be Responsible for Regulating Melanoma Growth & Metastasis? In‐vitro studies based on treatments of human melanoma cell lines (BLM and 1205Lu) with sex steroids, IL‐8, curcumin and active vitamin‐D3
Authors: Ramaraj Pandurangan 
Published: April 2020

Previous clinical studies indicated that menstruating females were better protected in melanoma than post‐menopausal women and men of any age. But, the mechanism responsible for protection in menstruating females was not investigated. In addition, epidemiological data showed an increased male mortality in melanoma. Our in‐vitro study showed female sex hormone progesterone significantly inhibited human melanoma cell growth. Elisarray showed that progesterone action was mediated by a specific suppression of pro‐inflammatory cytokine IL‐8. So, the effect of male sex hormones androstenedione (AD) and testosterone (T) on melanoma cell growth was checked. AD and T also suppressed cell growth and IL‐8 secretion. But, addition of progesterone (10μM) along with androgens showed an additive effect on the inhibition of melanoma cell growth and IL‐8 suppression. This observation gave the idea of protective function of progesterone in melanoma, which was experimentally observed by a significant decrease in in‐vitro migration and adhesion functions. As steroids (P, AD, T) targeted IL‐8 for their actions, effect of vit‐D3 on melanoma cells was checked. Active form of vitamin‐D3 (25 μM) also targeted IL‐8 and decreased cell growth, suggesting IL‐8 could be regulating melanoma cell growth. In order to check whether IL‐8 regulated melanoma cell growth, IL‐8 was directly added to melanoma cells and endogenous IL‐8 was suppressed by 2 hrs pre‐treatment with curcumin. Addition of IL‐8 (1 ng/ml) to 1205Lu melanoma cells stimulated cell growth to 117%, whereas suppression of IL‐8 by curcumin (100 μM) pre‐treatment decreased cell growth to 24%. Similar results were obtained with BLM cells. This brought IL‐8 into focus as an important molecule regulating melanoma cell growth. Further in‐vitro experiments to restore curcumin (25 μM) pre‐treated melanoma cell growth (71.5%) by the addition of IL‐8 (100 ng/ml) resulted in a near complete restoration of cell growth (95.3%) in 1205Lu melanoma cells, suggesting IL‐8 could be
the molecule regulating melanoma cell growth. Similar results were observed with BLM cells. In addition, in‐vivo conditional expression of IL‐8 in nude mouse by Dr. Singh et al., indicated involvement of IL‐8 in melanoma growth and metastasis.ConclusionBoth in‐vitro and in‐vivo studies indicated that IL‐8 alone could be responsible for regulating melanoma growth and metastasis. Hence, IL‐8 could be targeted to arrest melanoma growth and metastasis in‐vivo.
Kinetic and Mechanistic Characterization of a Potent and Selective Inhibitor for Human AXL Receptor Tyrosine Kinase
Authors: Chen Yu , Miles Dillon H. , Udyavar Akshata , Cho Sean , Becker Annette , Foley Corinne , Leleti Manmohan R. , Jin Lixia , Young Stephen W. , Powers Jay P. , Walters Matthew J. , Zhao Xiaoning 
Published: April 2020

The AXL receptor tyrosine kinase (AXL) is a member of the TAM RTK family comprising TYRO3, AXL and MER. AXL signaling is activated by binding of the growth arrest‐specific protein 6 (Gas6) or vitamin K‐dependent protein S (PROS1), which subsequently induces homodimerization and autophosphorylation, thereby initiating a conventional RTK signaling pathway. Maximal stimulation requires an extracellular lipid, phosphatidylserine (PtdSer).Activation of AXL regulates an array of signal transduction pathways, including those mediating cell survival, proliferation and migration, as well as promoting an immunosuppressive phenotype within the tumor microenvironment
1,
2. AXL has been shown to be highly expressed in sarcoma, renal cell carcinoma, pancreatic adenocarcinoma and other types of tumors, correlative with poor prognosis in cancer patients. Furthermore, AXL has been shown to facilitate both intrinsic and acquired resistance to multiple anti‐cancer drugs
3, suggesting therapeutic targeting of AXL may be an effective anti‐cancer strategy.We have developed a potent, reversible and competitive small molecule AXL inhibitor. This inhibitor (Compound 1) inhibits the activity of recombinant human AXL kinase domain with nanomolar potency, as determined by detection of phosphorylated substrate using homogeneous time‐resolved fluorescence (HTRF). Compound 1 is also highly selective against TYRO3, MERTK and MET kinase domains. The compound binds to the intracellular AXL kinase domain with a nanomolar dissociation rate constant measured by monitoring displacement of a competitive fluorescent tracer using bioluminescence resonance energy transfer (BRET). In order to assess the inhibitory effect of the compound on downstream signal transduction, AXL autophosphorylation‐induced SH2 translocation was determined using an AXL PathHunter® assay and phosphorylation of AKT Ser473 induced by AXL activation was also assessed by AlphaLISA.Support or Funding Information
Characterizing the Function of Anti‐CRISPR protein AcrIIA11
Authors: del Banco Serena Bautista , Kaiser Brett , Forsberg Kevin , Malik Harmit , Stoddard Barry 
Published: April 2020

Bacteria and the viruses that infect them are engaged in an evolutionary arms race that has driven the development of bacterial defense mechanisms and phage countermeasures to those defense mechanisms. One instance of this evolutionary competition is the development of the CRISPR‐Cas system, which enables the recognition and destruction of phage DNA. In response to this defense, phages have evolved anti‐CRISPR proteins that inhibit CRISPR‐Cas activity and promote phage infection. It is thought that many anti‐CRISPR proteins exist in nature, but only a handful have been identified and their mechanism of inhibition characterized. The goal of this project is to understand the mechanism by which a recently identified anti‐CRISPR protein, AcrIIA11, inhibits Streptococcus pyogenes Cas9 (SpyCas9). To address this, we have performed in vitro DNA cleavage and protein binding assays with purified components. We have determined the following: AcrIIA11 effectively inhibits Cas9 cleavage at an AcrIIA11: Cas9 ratio of 8:1; AcrIIA11 interacts directly with the Cas9 protein; homologs of AcrIIA11 show a range of ability to inhibit Cas9 activity but do no inhibit as well as AcrIIA11; and the C‐terminus of AcrIIA11 is not required for binding to Cas9. In future studies, we will test AcrIIA11 interaction with a wider range of Cas9 orthologs. From these results, we have gained a broader understanding of how AcrIIA11 interacts with SpyCas9.Support or Funding InformationSeattle University Summer Undergraduate Fellowship (Peach Foundation)
Heart Rate Variability during Heat Exposure is not Affected by Short‐term Passive Heat Acclimation in Young Healthy Participants
Authors: Gendron Philippe , Gravel Hugo , Barry Hadiatou , Gagnon Daniel 
Published: April 2020

INTRODUCTIONHeat acclimation attenuates the increase in heart rate during heat exposure. This heat acclimation‐induced bradycardia has been associated with increased stroke volume due to blood volume expansion. However, exercise‐induced heat acclimation also modulates cardiac parasympathetic activity, as measured through heart rate variability (HRV). Therefore, it is possible that modulation of cardiac autonomic activity could contribute to the effect of heat acclimation on heart rate during heat exposure. The purpose of this study was to determine if HRV during heat exposure is modified by short‐term passive heat acclimation.METHODSFifteen healthy adults (27 ± 5 years, 5 females/10 males) underwent heat exposure in a water‐perfused suit to increase esophageal temperature (Tes) by 1.2°C, before and after a 7‐day controlled hyperthermia protocol. During heat exposure, R‐R interval was measured continuously with a 5‐lead electrocardiogram and used to calculate heart rate (HR), mean normal‐to‐normal intervals (NN), standard deviation of NN intervals (SDNN), root mean square of successive NN interval differences (RMSSD), low‐frequency (LF) and high‐frequency spectral power (HF) and the LF‐to‐HF power ratio (LF/HF). The acclimation protocol consisted of hot water immersion to elevate and subsequently maintain rectal temperature ≥38.6°C for 60 minutes once a day for 7 consecutive days. Variables were compared between the pre and post acclimation visit at baseline and at increases in Tes of 0.6°C and 1.2°C.RESULTSHeat acclimation lowered resting Tes (36.81 ± 0.29 to 36.53 ± 0.32°C, P<0.001) and, consequently absolute Tes during heat exposure. When analyzed as a function of the change in Tes from baseline, no difference was observed for HR (P=0.072) at baseline (59 ± 10 vs. 57 ± 9 bpm), +0.6°C (88 ± 12 vs. 86 ± 11 bpm), and +1.2°C (103 ± 13 to 99 ± 12 bpm). Similarly, NN (baseline: 1049 ± 172 vs. 1081 ± 162 ms, +0.6°C: 691 ± 104 vs. 705 ± 100 ms, +1.2°C: 595 ± 74 vs. 600 ± 96 ms, P=0.295), SDNN (baseline: 84 ± 38 vs. 90 ± 37 ms, +0.6°C: 43 ± 15 vs. 45 ± 15 ms, +1.2°C: 28 ± 9 vs. 31 ± 8 ms, P=0.294) and RMSSD (baseline: 83 ± 49 vs. 93 ± 57 ms, +0.6°C: 19 ± 9 vs. 19 ± 14 ms, +1.2°C: 9 ± 4 vs. 9 ± 3 ms, P=0.336) did not differ after heat acclimation. No effect of heat acclimation was also observed for LF (P=0.339), HF (P=0.509) and LF/HF ratio (P=0.449).CONCLUSIONSThese results suggest that short‐term, passive and isothermic heat acclimation does not modulate cardiac autonomic activity during passive heat exposure in healthy young adults.Support or Funding InformationNatural Sciences and Engineering Research Council of Canada, Canada Foundation for Innovation and Montreal Heart Institute Foundation.
Using an Asparagine Synthetase Inhibitor to Reverse Chemotherapeutic Resistance in Leukemic Cell Lines
Authors: St. Laurent Andrea , Train Tonya Laakko 
Published: April 2020

Asparaginase (ASNase) is one of the first‐lines of chemotherapy used in the treatment of acute lymphoblastic leukemia (ALL). It breaks down asparagine in the body forcing the cell to undergo apoptosis. Yet, some patients develop resistance to ASNase treatment. Asparagine is produced in the cell by the enzyme asparagine synthetase (ASNS). One explanation for resistance could be increased ASNS expression leading to the production of more asparagine than can be broken down. Here, we investigated whether using a competitive ASNS inhibitor, albizziine (Alb), to decrease ASNS activity would reverse ASNase resistance in leukemic cell lines. Two human leukemic cell lines with varying ASNS expression were utilized, Jurkat and HL‐60. Real time‐PCR analysis showed an 8.9‐fold higher level of ASNS mRNA in HL‐60 relative to Jurkat. In addition, that HL‐60 was resistant and Jurkat sensitive to ASNase‐induced apoptosis; as determined by staining the cells with Annexin V‐FITC and flow cytometric analysis. After 24 hours, 0.1 IU ASNase treatment resulted in a 43.27% increase in apoptosis in Jurkat cells, but no significant increase in HL‐60 cells. The addition of the ASNS inhibitor, Alb, in combination with ASNase resulted in increased apoptosis in both cell lines. HL‐60 apoptosis increased 6‐fold when treated with a combination of 0.1 IU ASNase and 1mM Alb. Alb also increased Jurkat sensitivity to 0.1 IU ASNase from 43.27% apoptosis with ASNase alone to 67.15% in combination with ASNase. Alb alone did not induce any significant death. These results suggest that the ASNS inhibitor, Alb, can restore sensitivity to ASNase induced death in leukemic cell lines and therefore warrants further investigation into its role in reversing ASNase chemotherapeutic resistance.Support or Funding InformationThis work was supported by the Honors Program at Elon University, Elon Undergraduate Research Program, and Glen Raven grant.
Optimization of a bacterial‐three hybrid assay for discovery and characterization of sRNA‐binding proteins
Authors: Mansky Rachel , Wang Clara , Hegner Courtney , Berry Katherine E. 
Published: April 2020

Non‐coding RNAs regulate gene expression in every domain of life. In bacteria, small RNAs (sRNAs) regulate gene expression in response to stress and are often assisted by protein chaperones. Hfq is an RNA chaperone protein that, through RNA interactions on distinct surfaces of its hexameric structure, supports many sRNAs to regulate translation and stability of their mRNA targets. Though Hfq is well characterized in E. coli and some additional model bacteria, Hfq homologs have only been identified in ~50% of sequenced bacteria, leading to speculation that additional RNA chaperone proteins may play important roles in sRNA function in other bacteria. We have recently developed a bacterial three‐hybrid (B3H) assay that detects the binding of E. coli sRNAs with multiple RNA chaperone proteins. This assay couples the transcription of a genetic reporter to the interaction of a DNA bound “bait” RNA (e.g. an sRNA) and an RNAP‐fused “prey” protein (e.g. Hfq). Successful interaction between RNA and protein stabilizes RNA polymerase at a test promoter and activates reporter gene expression. While this assay current detects numerous high‐affinity RNA‐protein interactions, the signal‐to‐noise makes it challenging to detect weaker interactions. In order to lay the foundation to search for new bacterial RNA‐binding proteins, we are using Hfq‐sRNA interactions as a model system to optimize the system, so that weaker RNA‐protein interactions can be reliably detected. Here we will present our efforts to improve the assay’s signal‐to‐noise ratio by adjusting the sequence, concentration, and spacing of different components within the B3H assay. With these improvements, we will work to identify novel protein‐RNA interactions, as well as dissect the binding mechanisms of these interactions.Support or Funding InformationThis work was supported by National Institutes of Health [R15GM135878], Mount Holyoke College and the Henry Luce foundation.
SPARC: Catheter‐Free Wireless Measurement of Feline Bladder Pressures Using Intravesical Sensor
Authors: Majerus Steve J.A. , Panda Binit , Rietsch Anna , Deng Kangli , Hanzlicek Brett , Mrowca James , Damaser Margot S. , Bourbeau Dennis J. 
Published: April 2020

Introduction and ObjectiveIn research animal models, catheterization for cystometry requires anesthesia which affects neuro‐urological pathways, or animal restraint, limiting measurement time and social behaviors surrounding natural bladder filling and micturition. To overcome this, we developed a catheter‐free, wireless, intravesical pressure sensor for use in conscious, untethered felines. This study validated sensor function and physiologic outcomes over 4‐week implantations, including (to our knowledge) the first untethered catheter‐free wireless recordings of bladder pressure during bladder filling and voiding.MethodsSensor performance was first validated on the bench. Sensors were then encapsulated in layers of medical epoxy and silicone and sterilized by ethylene oxide gas prior to implantation. Implantations were performed on 6 male felines: 2 were sham (no device), 2 implants were inactive devices, and 2 used active devices measuring 18 mm × 12 mm × 5.6 mm. Devices were implanted into the bladder lumen through a 10‐cm detrusor incision, which was stretched on insertion and then sutured. Anesthetized cystometry and urine collection was performed immediately before and after surgery, and at 2 and 4 weeks after implantation. Conscious data collection and behavioral video recordings were performed 3 times/week. Data collection used a small animal‐worn radio harness which received sensor transmissions and logged data to a MicroSD card. Devices were explanted after 4 weeks.ResultsAll animals showed a similar decrease in bladder capacity following surgery (sham surgery and implant). All devices remained patent without obstructing the bladder for 4 weeks; one device stopped transmitting at 12 days and one worked through 4 weeks. Wireless pressure data was linearly correlated with spontaneous reflex contractions during anesthetized urodynamics (R2 = 0.96). Conscious data recording was performed on 11 occasions, producing over 200 minutes of catheter‐free pressure recordings. Animals entered and used litter boxes freely while data were recorded to the radio harness. Recorded pressures during voiding were confirmed against simultaneous video recording.ConclusionsSmall wireless, intravesical sensors permitted catheter‐free recordings of bladder pressure in felines for 30 days, including voluntary voiding contractions. Translation of this technology could enable urethrally‐inserted sensors for catheter‐free, wireless ambulatory urodynamics over longer time periods than is feasible with catheters.Support or Funding InformationThis work was funded by the NIH Stimulating Peripheral Activity to Relieve Conditions (SPARC) program, NIH grant number OT2OD023873.