bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inflammation‐induced Extracellular Vesicles Cause Endothelial Barrier Injury
Authors: Chatterjee Victor , Yang Xiaoyuan , Cha Byeong , Creasy Alexandria , Zheng Ethan , Ma Yonggang , Yuan Sarah Y. 
Published: April 2020

Extracellular vesicles (EVs) are a heterogenous population of sub‐micron sized vesicles released by cells during physiological or pathological stimulation. Circulating vesicles not only serve as important diagnostic/prognostic biomarkers, but also interact with blood or vascular cells and regulate multiple cellular processes by transferring bioactive cargo. In this study, we characterized EV production and cargo signature in the blood of healthy human subjects and burn patients, as well as in cultured human endothelial cells (ECs) after inflammatory stimulation. We also examined the effects of EVs on endothelial barrier structure and function. The results showed that the plasma level of EVs was increased during sterile inflammation in burn patients, with a significant portion of them derived from leukocytes and the endothelium. Interestingly, the EVs from burn patients expressed higher levels of c‐Src, protein kinase C and focal adhesion kinase, compared to EVs from healthy blood donors. In cultured ECs treated with tumor necrosis factor alpha, there was an increased production of EVs into the culture media. Furthermore, treating endothelial cells with EVs induced myosin light chain and VE‐cadherin phosphorylation and actin stress fiber formation in concomitance with adherens junction discontinuity. Functionally, EV treatment caused an increase in albumin flux across endothelial monolayers in a concentration‐dependent manner. EVs derived from c‐Src knockdown parent ECs displayed an attenuated effect on barrier protein phosphorylation and permeability. Likewise, pharmacological inhibition of Src activity reduced EV‐induced protein phosphorylation and barrier dysfunction in endothelial cells. Together, the data suggest that EVs produced during inflammation carry protein kinases capable of damaging the endothelial barrier.Support or Funding InformationNIH grants HL126646, HL070752 (to SYY), and GM097270. The human blood study was approved by the University of South Florida IRB and supported by the institutional research funds.
Ras Structure, Dynamics and Conformational States Assessed by MD Simulations and Solution Wide angle X‐ray Scattering
Authors: Volmar Alicia Yvette , Guterres Hugo , Zhou Hao , Mattos Carla , Makowski Lee 
Published: April 2020

Ras is a small GTPase that is involved in up to 30% of cancers. A wealth of evidence suggests that despite high sequence similarity of the Ras isoforms, H‐Ras, K‐Ras, and N‐Ras, there are distinct differences in signaling, localization, mutation position, and outcomes in cancer. Even in the absence of the C‐terminal hypervariable region (HVR), there are differences between the isoforms in the rates of GTP hydrolysis and in the details of Ras structure and dynamics. Here we present accelerated molecular dynamics simulations paired with solution x‐ray scattering that reveal differences in the conformational sampling of H‐Ras, K‐Ras4B, and N‐Ras. Specific interactions within water‐mediated allosteric networks are altered by the presence of isoform specific residues that impact accessibility to the catalytic state. Thus, the isoforms sample the same main three conformational states, but the population of each one is shifted by changes driven by isoform‐specific residues that may be associated with fine‐tuning preferences for signaling through distinct pathways and susceptibility to specific mutations observed in cancers.Support or Funding InformationNSF MCB‐1517295
HMGB1‐TLR4 in The Brainstem Nuclei Mediates Fructose‐induced Metabolic Syndrome
Authors: Ho Chiu-Yi , Chen Hsin-Hung , Cheng Pei-Wen , Lin Yu-Te , Tseng Chin-Jiuun 
Published: April 2020

The metabolic syndrome caused by excessive consumption of fructose is one of a variety of abnormal physiological phenomena, which is related to cardiovascular diseases. Our previous study reported that hypertension and central insulin resistance in WKY rats were caused by fructose intake. Several studies have been reported that the intake of fructose causes central inflammation. Toll‐like receptor 4 (TLR4) play a key role of innate immune signaling and has been implicated in fructose‐induced metabolic syndrome rats. We analyzed systolic blood pressure, biochemical parameter, and TLR4‐signaling pathway of WKY rats and fructose‐intake rats treated with vehicle or CLI‐095 (12 mg×d−1 for 14 days through osmotic mini‐pump). We found that the systolic blood pressure of rats treated CLI‐095 was improved to the normotensive group. The body weight change was recovered to the rats treated with the vehicle. Serum glucose treated with CLI‐095 was restored and stabilized compared with the fructose group. Immunoblotting results showed HMGB1 and TLR4 rather than TLR2, TLR7, TLR9 were induced in the brainstem nuclei area. MyD88, phosphorylated TGF beta‐activated kinase 1 (TAK1) and JNK were inhibited in the CLI‐095 group. Neuroinflammatory indicator iNOS was reduced in the therapy group. These data demonstrated that TLR4 in the central brain participates in the regulation of blood pressure, glucose, and body weight, which suggested HMGB1‐TLR4 might be a potential target for therapeutic interventions in the condition with metabolic syndrome combined with neuroinflammation.Support or Funding InformationThis work was supported by the Ministry of Science and Technology grants 107‐2320‐B‐075B‐001 (to P.W.C.) and 107‐2320‐B‐075B‐002‐MY2 (to C.J.T.) and Kaohsiung Veterans General Hospital grants VGHKS108‐162 (to Y.T.L.) and VGHUST108‐G3‐1‐3 (to Y.T.L.).
Role of Stromal Interaction Molecule 1 in Arteriogenesis
Authors: Frost Michaela , Belmadani Souad , Matrougui Khalid 
Published: April 2020

IntroductionArteriogenesis is a vital process for maintaining blood supply in the event of abrupt obstruction of perfusion such as cardiac ischemia. Here, we sought to determine whether stromal‐interaction molecule 1 (STIM1) is a key molecular mechanism involved in arteriogenesis.HypothesisWe previously reported that disrupting STIM1 in vascular smooth muscle cells (VSMC’s) protects the heart against chronic ischemia; likely through the induction of arteriogenesis. We hypothesize that disrupting STIM1 specifically in VSMC’s results in greater cellular proliferation and migration, which subsequently aids in arteriogenesis.MethodsWe isolated VSMC’s from mice with a genetic knockdown of STIM1 (VSMCStim1−/−) and also from wild‐type mice (VSMCStim1+/+). We cultured these VSMC’s in vitro and measured well‐known anti‐angiogenic factors including; thrombospondin‐1 (TSP‐1), hydrogen peroxide‐inducible clone 5 (Hic‐5), and extracellular signal‐regulated kinase (ERK 1/2). Additionally, we assessed the levels of pro‐angiogenic agent, AMP‐activated protein kinase (AMPK). Lastly, we assessed VSMC proliferation and migration after scratch‐assay injury.ResultsUnder basal conditions, Western blot analysis revealed that anti‐arteriogenic TSP‐1, Hic‐5, and phosphorylated ERK1/2 expressions were significantly decreased in VSMCStim1−/− when compared to VSMCStim1+/+. Western blotting also revealed that pro‐arteriogenic AMPK expression was increased in VSMCStim1−/− relative to VSMCStim1+/+. Moreover, using real time PCR, we found that TSP‐1 mRNA levels were significantly reduced in VSMCStim1−/− versus VSMCStim1+/+. Finally, the scratch‐assay injury revealed that VSMCStim1−/− migrate more efficiently than VSMCStim1+/+.ConclusionOur data illustrated that disrupting STIM1 in VSMC’s attenuates arteriogenic antagonists and enhances pro‐arteriogenic factors indicating that STIM1 as an important mechanism in arteriogenesis. Therefore, lowering STIM1 expression specifically in VSMC’s could be a potential therapy for conditions such ischemic heart diseases.Support or Funding InformationAHA‐34380220
Skeletal muscle‐specific PFKFB3 expression rescues ischemic myopathy by enhancing glycolytic flux
Authors: Salyers Zachary R. , Thome Trace , Le Dennis , Coleman Madeline , Ryan Terence E. 
Published: April 2020

INTRODUCTIONPeripheral artery disease (PAD) is caused by atherosclerotic occlusion in the lower extremities which leads to a spectrum of life‐altering symptomatology including claudication, ischemic rest pain, and gangrene requiring limb amputation.
Current treatment approaches for PAD are focused solely
on re‐establishing blood flow to the ischemic tissue, implying that blood flow is the decisive factor that determines whether or not the tissue survives. Unfortunately, clinical trials aimed to enhance angiogenesis have failed, suggesting the need to consider therapies that might also benefit other tissues in the ischemic limb, such as skeletal muscle. Under conditions of low oxygen cells must efficiently switch to non‐aerobic metabolism in order to maintain a cellular energy charge, which if dissipated with initiate necrotic cell death. The objective of this study was to determine if muscle‐specific overexpression of 6‐phosphofructo‐2‐kinase/fructose‐2,6‐bisphosphatase 3 (PFKFB3), an activator of glycolysis, could ameliorate ischemic myopathy in mice subjected to hindlimb ischemia.METHODS AND RESULTSTwelve‐week old male and female BALB/cJ mice (N=36) received intramuscular injections (5×1011 vg) of AAV9 encoding the PFKFB3 transgene or a GFP control driven by a skeletal muscle‐specific gene promoter (human skeletal actin, HSA). AAV‐expression was verified using immunofluorescence imaging, mRNA, and protein analysis. Three weeks following AAV injection, mice underwent unilateral hindlimb ischemia by ligation and excision of femoral artery. A sham surgery group underwent identical surgical procedure without ligation/excision. Mice were monitored for 28 days post‐surgery. Laser Doppler perfusion assessments showed no difference in perfusion in either the distal paw or tibialis anterior (TA) muscles (P>0.48 using two‐way ANOVA) between and control and PFKFB3‐treated mice. Ex vivo assessment of muscle contraction was performed in isolated extensor digitorum longus (EDL) muscles. Muscle cell specific expression of PFKFB3 significantly improved maximal force production following hindlimb ischemia (11.3 ± 2.6 N/cm2 vs. 6.1 ± 2.4 N/cm2 in AAV‐HSA‐GFP mice, P = 0.0147; Sham = 16.2 ± 2.4 N/cm2). Histological analysis of skeletal muscle confirmed a decrease in ischemic injury following AAV‐HSA‐PFKFB3 treatment.CONCLUSIONSThese data demonstrate that PFKFB3‐mediated enhancement of glycolysis in the ischemic limb muscle is sufficient to induce a metabolic shift that protects against ischemic myopathy. Our results highlight a potential causal role for metabolism in the pathology that befalls the ischemic limb tissues.Support or Funding InformationSupported by American Heart Association Grant 18CDA34110044 to TER.
Enteropathogenic Escherichia coli (EPEC) infection inhibits intestinal vitamin C transporter function and expression: in vitro and in vivo studies
Authors: Heskett Christopher W. , Teafatiller Trevor , Hennessey Carly , Gareau Melanie G. , Marchant Jonathan S. , Said Hamid M. , Subramanian Veedamali S. 
Published: April 2020

Enteropathogenic Escherichia coli (EPEC) is a food‐borne pathogen and causes enteric illnesses in children. EPEC infection is often associated with malnutrition of the host, especially in individuals experiencing severe and prolonged infection, and/or in those who are nutritionally compromised. While EPEC infection impacts nutrient transporter function and expression in intestinal epithelial cells, to date the consequences of EPEC infection on intestinal absorption of ascorbic acid (AA) are not known. Therefore, we investigated this issue using human intestinal epithelial Caco‐2 cells (in vitro) and mouse (in vivo) models. Infecting Caco‐2 cells with EPEC (WT) markedly inhibited AA uptake. EPEC mutants (ΔescN, ΔespA, ΔespB and ΔespD) did not affect AA uptake, whereas ΔespF and ΔespG/G2 mutants significantly inhibited AA uptake in Caco‐2 cells. Further, we observed significantly reduced expression of both hSVCT1 and hSVCT2 protein and mRNA levels upon infection. Similarly, infecting mice with EPEC (WT) significantly inhibited AA uptake and also reduced the expression of both mSVCT1 and mSVCT2 protein and mRNA levels in jejunum and colon. Studies have shown that epigenetic mechanisms (microRNA) play a role in mediating responses to bacterial infection in the intestine. Therefore, we determined miR103a, miR141 and miR200a expression levels, which were recently shown to regulate SVCT1 and SVCT2. Data from in vitro and in vivo models showed that all three microRNAs were up‐regulated significantly upon EPEC infection. In addition, expression of the accessory protein human glyoxalate reductase/hydroxypyruvate reductase (hGRHPR), which regulates the SVCT1 function, was also markedly decreased by EPEC in both models. These findings suggest that in intestinal epithelial cells, EPEC infection markedly inhibits AA uptake via dysregulation of both SVCT1 and SVCT2 expression.Support or Funding InformationSupported by NIH grants DK 107474, DK 58057, DK 56057, MH108154, GM088790, and a grant from the DVA
Elimination of the "essential" Warburg effect in mammalian cells through a multiplex genome engineering strategy
Authors: Lewis Nathan E. 
Published: April 2020

Innovative genome editing technologies are accumulating and are rapidly elucidating the genetic basis of many cell functions. However, many disease phenotypes and physiological processes are governed by complex networks involving many gene products. Thus, numerous phenotypes need to be unraveled using multiplex genome editing techniques and in silico analysis. Furthermore, these approaches must further leverage legacy knowledge to identify the genes involved and understand the cell response. As an example, we unraveled the core cellular network controlling the Warburg effect, also known as aerobic glycolysis. This effect involves the tendency of rapidly‐proliferating cells to consume excess glucose and secrete copious amounts of lactic acid, despite having adequate oxygen for more efficient oxidative phosphorylation. This response is a hallmark of cancer, immune cell expansion, and other processes with rapidly proliferating cells. However, efforts to test the purpose of Warburg metabolism have been stymied by the difficulty to generate cell lines that are unable to produce lactic acid, since genes involved have proven to be essential or synthetic lethal in immortalized cells. We discovered a genetic circuit involving multiple genes that control lactic acid secretion, and using a multiplex genome editing with CRISPR, we successfully eliminated lactic acid secretion and enabled the deletion of multiple "essential" genes. Surprisingly, the cells show improved metabolic and growth phenotypes, despite the elimination of this fundamental metabolic activity. To understand how immortalized mammalian cells can cope without this seemingly essential metabolic process, we conducted a comprehensive analysis of these cell lines using time‐course RNA‐Seq, metabolomics, and analysis with a genome‐scale metabolic network model we have developed for Chinese hamster ovary cells1. Thus, through a multiplex metabolic engineering effort and comprehensive systems biology analysis, we have been able to engineer out a hallmark phenotype of proliferating cells and begin to understand now a cell can survive without a seemingly essential process.Support or Funding InformationThe Novo Nordisk Foundation Center for Biosustainability (NNF10CC1016517)
Elevated maternal linoleic acid alters placental fatty acids, nutrient transporters and inflammatory proteins
Authors: Hryciw Deanne Helena , Shrestha Nirajan , Sleep Simone , Cuffe James , Holland Olivia , Perkins Anthony , McAinch Andrew 
Published: April 2020

Linoleic acid (LA) is the major omega‐6 fatty acid which is obtained from our diet. During pregnancy, LA is required for adequate fetal growth and development. For the growing fetus LA can only be obtained from the maternal diet, and is transferred from the maternal to fetal circulations by the placenta. At this time, in Western societies, we are overconsuming LA during pregnancy. Omega‐6 is metabolised by FADS1 and FADS2, which also metabiolise omega‐3. The ratio of omega‐6 to omega‐3 is important for human health, as they are proinflammatory and anti‐inflammatory, respectively. Therefore, the aim of this study is to determine if elevated maternal LA during pregnancy is alters placental fatty acids, nutrient transporter gene expression and inflammatory proteins.Female Wistar Kyoto rats were fed a diet low in LA (LLA‐1.44% of energy) or diet high in LA (HLA‐6.21% of energy) for 10 weeks before and during gestation. Following mating with a male consuming normal chow, offspring and maternal rats were sacrificed at embryonic day (E)20, and placenta were collected for analysis of placental fatty acids, nutrient transporters and inflammatory markers.In isolated placenta from pregnancies where mothers consumed an elevated LA diet, the concentration of LA was increased and the concentration of the omega‐3 fatty acid a‐linoleinic acid was decreased. Of interest, the downstream metabolite of LA, arachidonic acid was not altered in placenta from mothers consuming an elevated LA diet. mRNA expression of slc27a1 (fatty acid trasnport protein 1) was significantly downregulated in the male placenta from the dams fed with HLA, but not females. The mRNA expression of slc2a1 (glucose trasnporter 1) was significantly decreased in both male and female placenta from mothers fed the HLA diet. Further, the protein concentration of interleukin‐7 (IL‐7) was significantly decreased in both male and female placenta (labyrinth) from the dams fed with HLA, however there were no changes in protein expression of IL‐6 and TNF‐α in the labyrinth.In conclusion, a maternal diet high in LA alters fatty acid concentrations, nutrient transporters and inflammatory cytokines in the placenta. The consequences of this on offspring development, and therefore long term health require further investigation.Support or Funding InformationAllen Foundation (USA)
Relationship between COVID-19 death toll doubling time and national BCG vaccination policy
Authors: Akiyama Yutaka , Ishida Takashi 
Published: April 2020

AbstractIn this manuscript, we showed a statistically significant difference of the doubling times of the death toll between the group of countries with national universal Bacillus Calmette-Guerin (BCG) vaccination and the group without it for recent years. Based on a statistical test, the distributions of the doubling time of these two groups were significantly different (p=0.007). Miller et al. reported the relationship between BCG vaccination and mortality for COVID-19 based on deaths per million inhabitants. However, they did not take into account the differences in COVID-19 detection rates among the countries and the epidemic stages of the countries. Therefore we used a doubling time of the death toll as a more stable indicator instead. We also investigated the dependency of the BCG strains. Among the 42 BCG-vaccinated countries, the median doubling time of the eight countries using “Tokyo 172-1” strain at least partially (Japan, Iraq, Malaysia, South Korea, Philippines, Saudi Arabia, Pakistan, and Bangladesh) was 7.2 days, and that of the other 34 vaccinated countries was 5.5 days. Their distributions were also significantly different (p=0.026).
Hybrid Machine Learning Model of Extreme Learning Machine Radial basis function for Breast Cancer Detection and Diagnosis; a Multilayer Fuzzy Expert System
Authors: Mojrian Sanaz , Pinter Gergo , Joloudari Javad Hassannataj , Felde Imre , Szabo-Gali Akos , Nadai Laszlo , Mosavi Amir 
Published: April 2020

AbstractMammography is often used as the most common laboratory method for the detection of breast cancer, yet associated with the high cost and many side effects. Machine learning prediction as an alternative method has shown promising results. This paper presents a method based on a multilayer fuzzy expert system for the detection of breast cancer using an extreme learning machine (ELM) classification model integrated with radial basis function (RBF) kernel called ELM-RBF, considering the Wisconsin dataset. The performance of the proposed model is further compared with a linear-SVM model. The proposed model outperforms the linear-SVM model with RMSE, R2, MAPE equal to 0.1719, 0.9374 and 0.0539, respectively. Furthermore, both models are studied in terms of criteria of accuracy, precision, sensitivity, specificity, validation, true positive rate (TPR), and false-negative rate (FNR). The ELM-RBF model for these criteria presents better performance compared to the SVM model.
Multiscale 3-dimensional pathology findings of COVID-19 diseased lung using high-resolution cleared tissue microscopy
Authors: Li Guang , Fox Sharon E. , Summa Brian , Hu Bihe , Wenk Carola , Akmatbekov Aibek , Harbert Jack L. , Vander Heide Richard S. , Brown J. Quincy 
Published: April 2020

AbstractThe study of pulmonary samples from individuals who have died as a direct result of COVID-19 infection is vital to our understanding of the pathogenesis of this disease. Histopathologic studies of lung tissue from autopsy of patients with COVID-19 specific mortality are only just emerging. All existing reports have relied on traditional 2-dimensional slide-based histological methods for specimen preparation. However, emerging methods for high-resolution, massively multiscale imaging of tissue microstructure using fluorescence labeling and tissue clearing methods enable the acquisition of tissue histology in 3-dimensions, that could open new insights into the nature of SARS-Cov-2 infection and COVID-19 disease processes. In this article, we present the first 3-dimensional images of lung autopsy tissues taken from a COVID-19 patient, including 3D “virtual histology” of cubic-millimeter volumes of the diseased lung, providing unique insights into disease processes contributing to mortality that could inform frontline treatment decisions.