bluuebunny/crossref_metadata_2025_split huggingface dataset:
Endothelial Progenitor Cells Are Decreased in the Circulation of Patients with Sepsis
Authors: Burnham Ellen Lyda , Sutcliffe Diane , Edwards Michael , Taylor W. Robert , Moss Marc 
Published: June 2021

Background: Acute lung injury (ALI) and sepsis are associated with widespread endothelial injury. Elaboration of endothelial precursor cells from bone marrow that could participate in repair represents one mechanism to attenuate injury.Methods: Blood was obtained from 24 ALI and 12 septic patients within 72 hours of diagnosis. Peripheral blood mononuclear cells were isolated and cultured on fibronectin‐coated wells in endothelial‐specific medium. Numbers of endothelial progenitor colony‐forming units (EPC CFUs) were assessed after 7 days.Results: ALI and sepsis patients were similar for mortality, age, and severity of illness. 81% (9/11) of sepsis patients had septic shock;17% (2/12) had a pulmonary source for sepsis. 54% (13/24) of ALI patients had septic shock. ALI patients had higher EPC CFU numbers than did septic patients [median 56 (19–90) vs 19 (3–50), p<0.04)]. Comparing just patients with septic shock (ALI, n=13 vs. sepsis, n=9) revealed a trend for higher EPC CFUs in ALI patients [median 50 (17–93) vs 19 (11–46), p =0.09). No significant difference in EPC CFU numbers between those with and without septic shock were observed among those with ALI (p=0.58).Conclusions: More numerous EPC CFUs in those with ALI provides evidence for the role of lung injury in their mobilization. Alternatively, septic shock might hinder their release from the marrow.AHA Beginning Grant‐in‐Aid
Hyperglycemia‐induced reactive oxygen species are differentially regulated by estrogen in human endothelial cells
Authors: Chakrabarti Subhadeep , Davidge Sandra T 
Published: June 2021

Diabetes is a predisposing factor for atherosclerosis. High glucose generates reactive oxygen species such as superoxide and peroxynitrite which lead to pro‐atherogenic changes in the endothelium. Estrogen has a beneficial anti‐oxidant and anti‐inflammatory effect on the vascular endothelium. However, the beneficial effects of estrogen are absent in patients with diabetes. We investigated the effects of estrogen on endothelial cells in the context of pre‐existing hyperglycemia. Human umbilical vein endothelial cells (HUVEC) were used for the studies. Superoxide and peroxynitrite were detected by staining for Dihydroethidium and nitrotyrosine respectively. Enzymes were detected by western blotting. We found that high glucose increased levels of both superoxide and peroxynitrite in the endothelial cells. Estrogen administration had no effect on superoxide levels. Surprisingly, estrogen significantly reduced the peroxynitrite generated under high glucose conditions. On examining the expression of nitric oxide synthase isoforms, we found that estrogen increased eNOS levels under normal glucose, but not under high glucose. The iNOS levels were unchanged under all conditions. Our results show a novel selective anti‐oxidant effect of estrogen on hyperglycemia‐induced peroxynitrite in endothelial cells.This work has been supported by CIHR, HSF Canada and AHFMR.
BH4 protects endothelial progenitor cell number and function via suppressing thrombospondin‐1 expression in salt‐sensitive hypertension
Authors: Xie He‐Hui , Du Yan‐Hua , Channon Keith M. , Chen Alex F. 
Published: June 2021

Background: Endothelial progenitor cells (EPC) are both reduced and dysfunctional in hypertension that correlates inversely with its mortality, but the mechanisms are poorly understood. eNOS regulates EPC mobilization and function, but is uncoupled in DOCA‐salt hypertension due to reduced cofactor BH4. We tested the hypothesis that GTP cyclohydrolase I (GTPCH), the rate‐limiting enzyme of BH4 synthesis, protects EPC and its function in DOCA‐salt mice.Methods and Results: EPC were isolated from peripheral blood and bone marrow of wild‐type (WT), GTPCH transgenic (Tg‐GCH) and BH4 deficient hph‐1 mice. In WT DOCA‐salt and hph‐1 mice, EPC number was significantly reduced (flow cytometry and fluorescence microscopy, n=7–12, p<0.01), which was rescued in DOCA‐salt Tg‐GCH mice (n=5–8). Compared with WT Sham mice, both EPC adhesion and angiogenesis functions were impaired in WT DOCA‐salt and hph‐1 mice, which were reversed in DOCA‐salt Tg‐GCH mice. Superoxide level (DHE flow cytometry) in EPC was augmented in WT DOCA‐salt and hph‐1 mice, which was blunted in DOCA‐salt Tg‐GCH mice. Western blot showed that the secreted thrombospondin‐1 (TSP‐1, a key inhibitor of EPC function) from EPC was elevated in WT DOCA‐salt and hph‐1 but not in DOCA‐salt Tg‐GCH mice, which was prevented by NOS inhibitor L‐NNA. Conclusion: GTPCH/BH4 pathway protects EPC and its functions in DOCA‐salt hypertension b suppressing TSP‐1 expression.
Diverse TRPC heteromultimers form store‐operated channels in native vascular smooth muscle preparations
Authors: Albert Anthony , Saleh Sohag , Peppiatt‐Wildman Claire , Large William 
Published: June 2021

Store‐operated channels (SOCs) are activated following depletion of intracellular Ca2+ stores and the canonical transient receptor potential (TRPC) family of channels are possible molecular candidates of SOCs. Here we describe diverse properties and putative molecular identities of SOCs in different vascular preparations.In rabbit mesenteric (MA) and coronary artery (CA) myocytes SOCs were activated by the store depleting reagents BAPTA‐AM and cyclopiazonic acid and in 1.5mM [Ca2+]o these SOCs had conductances of about 2pS (Saleh et al. 2006) and 3 pS and reversal potentials (EREV) of about +20mV and −10mV respectively. In 0mM [Ca2+]o the conductances were about 7pS in MA and 3pS in CA whilst EREV were both about −10mV respectively, highlighting different biophysical properties of SOCs in these two preparations.MA SOCs were selectively inhibited by anti‐TRPC1/C5 whilst SOCs from CA were specifically inhibited by anti‐TRPC1/C5/C6. SOCs recorded from portal vein myocytes had similar biophysical properties to MA SOCs (Albert & Large, 2002) but were blocked by anti‐TRPC1/C5/C7.These data suggest that TRPC channels can form alternative heteromultimers with a similar SOCE function in different vascular smooth muscle preparations. Moreover, these data show that anti‐TRPC antibodies can be used as ‘immunopharmacological’ reagents with a remarkable degree of selectivity to determine the composition of heteromultimeric ion channel proteins in native tissue.Funded by British Heart Foundation and The Wellcome Trust.
Flow mediated dilation response to oscillatory vs. steady shear: evidence for the transduction of the mean shear stimulus
Authors: Pyke Kyra E. , Poitras Veronica , Tschakovsky Michael E. 
Published: June 2021

OBJECTIVE: 1) To compare the flow mediated dilation (FMD) response to an increase in brachial artery (BA) shear stress (SS) via forearm heating (FH) vs. forearm exercise (FE). 2) To isolate the effects of the oscillatory pattern of exercise SS. BA diameter (BAD) and mean blood velocity (MBV) were measured with ultrasound in 16 healthy subjects. BA MBV was elevated to the same mean level for 10min via 3 protocols. 1) FHstdy ‐ A steady MBV was created by controlled release of BA compression upstream of heat‐induced forearm vasodilation. 2) FHosc: rhythmic cuff inflation simulated exercise induced oscillations in MBV. 3) FE ‐ Rhythmic isometric handgrip exercise.RESULTS: The mean increase in shear rate (MBV/BAD) (±SD) was the same in all conditions (FHstdy: 52.2±14.1s−1; FHosc: 51.7±15.7s−1; FE: 50.1±13.0s−1 P=0.13). Neither the percent change in BAD (End‐trial: FHstdy: 7.0±3.0%; FHosc: 7.8±3.4%; FE: 6.7±3.0% P=0.20) nor the initial response speed (tau‐time to 63% of max response) (FHstdy:27.8±14.4s; FHosc: 22.6±16.7s; FE:25.9±23.3s P=0.69) were different between conditions.CONCLUSION: The FMD was determined by the mean shear independent of stimulus pattern (oscillatory vs. steady) and mode of increase (heating vs. exercise). These data suggest that the endothelium transduces the mean shear stimulus and indicate that exercise may provide a viable technique to investigate human FMD.Funded by NSERC, ACSM and HSFC
Investigating a Triple Congenic Rat Model to Determine Genes Contributing to Renal Failure
Authors: O'Meara Caitlin Claire , Lazar Josef , Moreno Carol , Provoost Abraham P. , Jacob Howard J. 
Published: June 2021

To find genes associated with kidney disease, the fawn‐hooded hypertensive (FHH) rat was crossed with the normotensive, renal resistant August × Copenhagen Irish (ACI) strain. We used a genetic mapping strategy to locate five quantitative trait loci (QTLs) on the rat genome that show linkage to measures of renal impairment (Rf1–5). Following this linkage analysis, single, double and triple congenic animals were made to demonstrate the synergistic relationship between the genes within the various Rf QTLs. Double and triple congenic animals containing Rf‐1 showed more marked measures of renal impairment, which indicates that genes within these QTLs are all interacting with one another to contribute to this complex disease. We have developed Rf‐1+3+4 triple congenic animals to investigate the interaction between these three QTLs. Our current focus is to analyze candidate genes in the Rf‐3 region.National Institute of Health and the Medical College of Wisconsin
Renin‐Angiotensin System and NAD(P)H Oxidase Activation in the Rostral Ventrolateral Medulla are involved in the Further Blood Pressure Elevation on High Sodium Diet in Spontaneously Hypertensive rats
Authors: Koga Yasuaki , Hirooka Yoshitaka , Araki Shuichirou , Konno Satomi , Kishi Takuya , Sunagawa Kenji 
Published: June 2021

Background: High salt diet (HS) causes sympathetic hyperactivity and increases blood pressure (BP) in spontaneously hypertensive rats (SHR). We previously demonstrated the reactive oxygen species (ROS) in the rostral ventrolateral medulla (RVLM) was increased more in SHR on a HS (8%) than a regular salt diet (0.5%: RS). This study aimed to elucidate whether the increased ROS in the RVLM of HS‐SHR is associated with central NAD(P)H oxidase activation and the pressor response on an HS diet is involved in renin‐angiotensin system (RAS) activation.Methods and Results: Male SHR were fed an HS or RS diet for 6 weeks. Systolic BP was significantly higher in HS‐SHR than in RS‐SHR (244±15 mmHg vs 188±20 mmHg at 12 weeks old, n=8, P<0.05). The angiotensin II type1 receptor (AT1R) protein expression in the RVLM was significantly increased more in HS‐SHR than in RS‐SHR (5.1±0.5 vs 3.4±0.3, n=6, P<0.05). The AT1R antagonist (valsartan) microinjected bilaterally into the RVLM induced a significantly greater BP depression in HS‐SHR than in RS‐SHR (Δ MAP/basal MAP: −13.2±2.1 % vs −20.9±2.2% n=5, P<0.05). NAD(P)H oxidase activity was significantly higher in HS‐SHR than in RS‐SHR (1.53±0.10 vs 1.25±0.10, n=9, P<0.05).Conclusions: These results suggest that the pressor response of SHR on an HS diet is mediated by RAS activation and the ROS increase is involved in the enhanced NAD(P)H oxidase activation in the RVLM.
Cardiovascular dynamics in healthy subjects with differing heart rate responses to tilt
Authors: Ramirez‐Marrero Farah A , Charkoudian Nisha , Zhong Liu , Eisenach John H , Joyner Michael J 
Published: June 2021

Orthostatic stress such as head‐up tilt (HUT) elicits a wide range of HR and BP responses among healthy individuals. In this study, we evaluated cardiovascular dynamics of subjects with different HR responses to HUT but without autonomic dysfunction. We measured BP (brachial artery) and HR (ECG) during 5 min of 60° HUT in 76 healthy young individuals, while norepinephrine (NE) was assayed during the final 30 s. We then chose 30 individuals based on the extremes of HR responses to HUT: 15 with the highest (ΔHR≥ 20 bpm) and 15 with the lowest response (ΔHR ≤10 bpm). Age and BMI were not different between groups; however, gender distribution was different (high: 5F, 10 M; low: 10F, 5M). Peak HR during HUT was 87.2±10.4 bpm in the high and 69.1±14.1 bpm in the low group (P< 0.05). Baseline HR was not different between groups. High HR responders had lower SBP at baseline (120.9±9.4 vs. 129.4±11.0 mmHg) and during HUT (119.9±9.7 vs. 131.4±13.1 mmHg). High HR responders also had higher plasma NE response to HUT (ΔNE: 156.9±82.1 vs. 89.0±48.0 pg/ml; P< 0.05). Higher HR with lower BP during HUT is consistent with normal baroreflex mechanisms of integration. Although inter‐individual variability appears to be a fundamental part of cardiovascular regulation, the mechanisms of these differences and the gender discrepancy requires further investigation.Supported by K23 RR17520, HL46493, NS32352, KL2 RR024151‐01.
Neural Precursor cells (NPCs) derived from cervical and upper thoracic spinal cord
Authors: Kim Yong‐Jung , Yoo Young‐Mi , Yoo Hyun‐TAE , Yoo Chan‐Jong , Lee Uhn 
Published: June 2021

Spinal cord injuries result in cellular loss that accompanies the destruction of descending motor and ascending tracts and leads to permanent damage with limited prospects for spontaneous repair. Neural stem cells are promising alternative to fetal tissues for cell therapies, primarily due to their self‐renewal and pluripotentially. The use of human derived neural stem cells has the additional advantage of yielding translational information that is relevant to clinical therapies.NPCs were taken from passages 5 through 13 and seeded into monolayer. The single cells began to cell division, growing into centipede shaped morphology at 5 days. When cells grew at approximately 80% confluence, the parts of cells formed a small cluster and became a large cluster through excellent cell division. Large clusters were center and slowly pulled adjacent cell and rolled up like carpet, and formed more lager cluster.
A mathematical model of collective cell motility and pattern formation
Authors: Szabo Andras , Czirok Andras 
Published: June 2021

Cell motility and its guidance through cell‐cell contacts is instrumental in vasculogenesis, when multicellular sprouts invade into avascular areas and eventually create a polygonal pattern. Sprout elongation depends on a continuous supply of endothelial cells, streaming along the sprout towards its tip.The collective motility and cell patterning was studied in vitro with 2D cultures. When grown on a suitable ECM substrate at high cell density, non‐contact inhibited cells such as BAEC, MDCK or human gliomas all exhibit streaming – adjacent cells moving in similar directions and thereby creating multicellular streams. At lower cell densities many cell lines (C6 gliomas, C2C12 myoblasts, 3T3 fibroblasts) form multicellular linear arrangements, similar to the multicellular vasculogenic sprouts.To explain these phenomena, we augmented the cellular Potts model with two features: (i) a cell polarization with an intrinsic persistence time, and (ii) an asymmetric cell‐cell attraction whereby surfaces of elongated cells become preferred adhesion substrates. We demonstrate that these two effects are sufficient to explain the observed abundance of streaming and sprouting behavior in cell cultures and in vivo.
MAIN AND ACCESSORY RENAL ARTERIES ‐ A MORPHOLOGICAL STUDY
Authors: Lall Kumud , Dhar Puspha 
Published: June 2021

The present work was undertaken to document the incidence of accessory renal arteries in the kidney specimens obtained from subjects of Indian origin.Comprehensive dissection carried out in the dissection hall of Anatomy Department of All India Institute of Medical Sciences (India) on forty cadavers over a period of five years revealed a single main renal artery on either side in 80% of the specimens. The mean length of the main renal artery was 31.05 ± 12 and 25.0 ± 9.5 mm on the right and left side respectively. Multiple (accessory) renal arteries were observed in 20% of the specimens with unilateral anomaly (15%) being more commonly encountered than bilateral anomaly (5%). The mean length of the accessory renal artery was 36.4 ± 10 and 36.6 ± 11 mm on the right and left side respectively. The accessory renal artery when present, invariably crossed the anterior aspect of the ureter.Familiarity about the possible variations in the renal arterial pattern are especially important for the personnel dealing wit kidney retrieval and transplantation, various endourologic procedures and innumerable interventional techniques. In the majority of such situations, it is the comprehensive knowledge of the renal arterial pattern which remains the key issue in determining the technical feasibility of surgical interventions as well as the post operative management.
NF90 binds novel human non‐coding RNAs
Authors: Mathews Michael B , Parrott Andrew M 
Published: June 2021

Proteins in the nuclear factor 90 (NF90) family of dsRNA binding proteins are abundantly expressed in a broad spectrum of vertebrate tissues and participate in many aspects of RNA metabolism. NF90, also known as DRBP76 and NFAR1, forms heterodimeric complexes with NF45 protein. We detected several small non‐protein‐coding RNAs that associate with NF90 in vivo. They include snaRs (small NF90‐associated RNAs), a novel family of RNAs that are unique to the African Great Apes and display a restricted tissue distribution in humans.The genes for 3 of these RNA species are located within the proximal promoters of protein‐coding genes and are transcribed by RNA polymerase III (Pol III) in the opposite direction to their ‘host’ Pol II genes. snaRs are highly structured RNAs, ∼117 nucleotides in length. The snaR‐G1 and snaR‐G2 genes are in the proximal promoters of chorionic gonadotropin genes CG □ 1 and 2, respectively, in locations shared by chimpanzee orthologs. The gene encoding a novel tRNAimet precursor is 242 bp upstream of the 5′‐end of NF45 mRNA, in a highly conserved position in vertebrates. The binding of NF90 to a pre‐tRNAimet transcript whose gene resides in the NF45 promoter is suggestive of an intricate feedback control mechanism. We speculate that NF90 regulates the transcription of specific protein‐coding genes through interaction with small non‐coding RNAs transcribed by Pol III.Supported by NIH grant AI034552.
Automated planar patch clamp: Multiple applications for miniaturized devices
Authors: Haarmann Claudia , Haythornthwaite Alison , Brueggemann Andrea , Stoelzle Sonja , Farre Cecilia , George Michael , Fertig Niels 
Published: June 2021

The Port‐a‐Patch is a miniaturized patch clamp rig which uses a planar borosilicate glass chip for performing electrophysiological recordings. Suction applied from the underside of the chip is used to attract a single cell to the recording site without the need for optical visualization. The Port‐a‐Patch has been successfully used for whole cell, perforated patch, and cell attached recordings of a variety of ion channels with high success rates (typically 60‐80%). Fast application of ligand is possible using the external perfusion system. Recordings from recombinant GABAA receptors (α1β2γ2) expressed in HEK293 cells will be shown. Examples of voltage‐gated ion channels recorded using the Port‐a‐Patch will also be shown, including NaV1.5 stably and Shaker K+ transiently expressed in HEK293 cells. The effect of temperature on the amplitude and kinetics of hERG channels will also be presented.One of the newest and most exciting aspects of planar patch clamping using the Port‐a‐Patch is the ability to perfuse the internal membrane of the cell, whilst maintaining a continuous recording during the solution exchange. The internal perfusion system for the Port‐a‐Patch allows the exchange of up to 8 different solutions. Exemplar traces will be shown for regulation of TRP V1 by internal as well as external regulators. Such ease with which the internal solution may be exchanged is a unique feature to Nanion products.
The Effect of Inhaled L‐arginine on Pulmonary Hypertension Induced by Hypoxia or Intravenous Arginase Infusion
Authors: Vrancken K , Power G G , Job L , Wilson S M , Blood A B 
Published: June 2021

BackgroundFailure of the pulmonary vasculature to produce nitric oxide (NO) results in elevated pulmonary vascular resistance (PVR). L‐arginine (L‐arg) deficiency may be etiologic in some types of pulmonary hypertension (PH).ObjectiveTo test the hypotheses that inhalation of L‐arg will attenuate PH induced by hypoxia or an intravenous infusion of arginase, and that depletion of plasma L‐arg will result in elevated PVR.Design/Methods15 healthy newborn lambs 5‐10 days of age were anesthetized and maintained on a mechanical ventilator. Pulmonary arterial (PAP) and venous pressure and cardiac output were measured. 12 lambs were exposed to 6 sequential 10‐min periods of hypoxia. Inhaled L‐arg or saline was administered prior to the 4th hypoxic episode. In an additional 3 sheep, intravenous arginase was infused. Inhaled L‐arg was then administered for 15 min.ResultsRepeated episodes of hypoxia resulted in a rapid selective onset of PH. L‐arg inhalation caused no significant difference in PAP, PVR, or exhaled NO as compared to saline controls. Arginase resulted in a rapid significant increase in PAP (p <0.001), and in PVR (p < 0.05). PAP and PVR both decreased gradually during L‐arg inhalation, returning to control values by the end of the arginase infusion.ConclusionsPlasma L‐arg is vital for the maintenance of low PVR. Preliminary results indicate that L‐arg inhalation may be effective in decreasing PH caused by L‐arg deficiency.
Macrophage Uptake of Unopsonized Staphylococcus aureus Strains: High‐Throughput Analysis by Scanning Cytometry
Authors: DeLoid Glen , Sulahian Timothy , Imrich Amy , Kobzik Lester 
Published: June 2021

Lung macrophages phagocytose unopsonized particles and pathogens via innate immune receptors such as scavenger receptors (SR). Signaling pathways for SR‐mediated phagocytosis of unopsonized bacteria likely govern the fate of ingested pathogens, but are poorly characterized. To allow high‐throughput screening (HTS) analysis, we developed a scanning cytometry assay to quantify phagocytosis of S. aureus by adherent human AM‐like macrophages. We compared the effects of receptor, signaling and cell process inhibitors (n = 7) on phagocytosis by human blood‐derived macrophages of a panel of live unopsonized S. aureus strains, (Wood, ATCC 29523, RN6390), as well as killed Wood strain, and latex beads. Differential fluorescent labeling of internalized vs. bound bacteria and image analysis of collapsed stacks of confocal sections in triplicate wells provided quantitation for ~500 cells per inhibitor per sample from three normal individuals. We found surprising heterogeneity of inhibition patterns among S. aureus strains, as well as between live and killed Wood strain, and between all S. aureus forms and unopsonized latex beads. The classic antagonist of SRs polyinosine inhibited uptake of latex beads and killed Wood strain, but had no effect on uptake of any live S. aureus strains. The data confirm the utility of the HTS assay, and suggest that receptor(s) other than SRs mediate uptake of live unopsonized S. aureus.Supported by NIH ESO11008 and ESO11903