bluuebunny/crossref_metadata_2025_split huggingface dataset:
An experimental model of restoration of renal blood flow in murine 2‐Kidney 1‐Clip hypertension
Authors: Grande Joseph Peter , Osman Mazen , Kashyap Sonu , Hu Zeng 
Published: November 2023

Renal artery stenosis (RAS) is a common public health problem, affecting up to 7% of individuals over 65 years of age. Optimal therapy for patients with RAS is controversial, as recent studies have indicated that revascularization via stenting fails to improve renal function or patient survival. Medical therapy is associated with high morbidity and mortality, primarily due to cardiovascular disease. However, morphologic correlates for reversibility following restoration of blood flow have not been adequately defined. The purpose of this study was to standardize an experimental model for the restoration of blood flow, employing a well characterized murine RAS model.Total N=10 C57B/6J male mice were used. RAS was induced on the right renal artery by putting a polytetrafluoroethylene cuff (N=6) and sham surgery was performed without cuff placement (N=4). To determine the feasibly of restoring the blood flow to the stenotic kidney, cuff was taken off at day 7 following the RAS surgery. Blood pressure measurements were done using tail cuff method at baseline, before taking cuff off and then every week until harvest. MRI images were captured using an Avance DRX 700WB spectrometer with a vertical 16.4 T wide bore magnet connected with the imaging tools at baseline, 3 days after putting the cuff on or sham surgery, and at 3 weeks after cuff off. The animals were harvested at day 28 following surgery and kidney weights are obtained.Baseline renal perfusion (1018±41.6 ml/100g/min) was significantly reduced (634.7±141.3 ml/100g/min, p=0.01) following cuff placement. Perfusion was restored to normal (955±59.8 ml/100g/min) at 28 days following cuff removal at 7 days after RAS. Similarly, volume of the stenotic kidney was significantly reduced (at day 3 after RAS 172±8.6 mm3) compared to baseline (206.3±4.4 mm3, p=0.0007). There was no significant difference in perfusion and volume after cuff off compared to baseline and sham groups. There was no significant difference in kidney weight between cuff‐off (167± 4.7 mg) and sham groups (163±9.95 mg). Also, there was no difference in heart weight between cuff off (150±3.7mg) and sham groups (148±6.7mg).We conclude that this model will provide the basis for determining the latest time point associated with recovery of renal structure and potential histopathologic markers that predict preservation of renal structure following cuff removal. Also, this model would provide the basis for determining efficacy of additional therapies to target inflammation, etc. to widen the “therapeutic window” during which restoration of renal blood flow is beneficial.Support or Funding InformationThis project is funded by National Institutes of health, NIAID R01 AI100911.
Vascular endothelial cell responses to increased hydrostatic pressure
Authors: Chung Kyukwang , Patterson Eric , Lawendy Abdel , Fraser Douglas , Cepinskas Gediminas 
Published: November 2023

Endothelial cell responses to mechanical forces such as shear stress and tensile stress have been a subject of intense investigations. However, there is a substantial lack of studies addressing the effects/mechanism of hydrostatic pressure on endothelial cell function. It is known that pathologies such as venous congestion, compartment syndrome etc., are closely associated to the increased intravascular and/or interstitial hydrostatic pressure.In this study we examined vascular endothelial cell (HUVEC) responses to increased hydrostatic pressure (IHP). To this end, HUVEC were seeded into μ‐Slide IV (ibidi) channels and grown to confluence. Subsequently, one end of the channel was connected to the pressure monitor and the other end was connected to the cell culture medium reservoir, which was elevated to the height to induce 30mmHg hydrostatic pressure within the channel under conditions of “no flow”. HUVEC were exposed to the IHP (30mmHg) for 4 hrs in 5%CO2 cell culture incubator at 37°C. Control HUVEC were cultured at ambient pressure (0mmHg) under the same conditions.The obtained results indicate that exposure of HUVEC to 30mmHg IHP results in: 1) prominent formation of F‐actin stress fibers (Phalloidin staining), 2) changes in VE‐cadherin junctional staining pattern, 3) induction of oxidative stress (DHR123 oxidation), 4) induction of apoptosis (caspase‐3 activity assay), and 5) increased neutrophil adhesion to HUVEC.These results indicate that increased hydrostatic pressure per se is a critical factor contributing to endothelial cell activation and dysfunction.Support or Funding InformationSupported by the grant from Lawson Health Research Institute (IRF‐28‐16)
miR‐16 Mediated MYB Gene Silencing Induces Fetal Hemoglobin Expression
Authors: Pounds Catherine R. , Takezaki Mayuko , Li Biaoru , Ward Christina , Lopez Nicole , Pace Betty S. 
Published: November 2023

Sickle cell disease (SCD) is an inherited blood disorder caused by a point mutation in the β‐globin gene affecting about 100,000 people in the United States and millions worldwide. Individuals living with this disease suffer from hemolytic anemia, progressive organ damage, and acute painful episodes. Fetal hemoglobin (HbF), a major genetic modifier of clinical presentation and progression of SCD, is of great interest due to its ability to inhibit sickle hemoglobin (HbS) polymerization and reducing erythrocyte damage. Variation in HbF levels among sickle cell patients is highly heritable and has been linked to the presence of single nucleotide polymorphisms (SNPs) in several genetic regulatory regions. In this study, DNA isolated from two cohorts of African American SCD patients with high and low HbF levels were analyzed by PCR‐based SNP analysis in the HBB, BCL11A, and HBS1L‐MYB (HMIP) gene regions. The presence of SNP alleles was then correlated with their clinical phenotype data to identify those associated with increased levels of HbF. Three SNPs in the BCL11A and HBB gene regions were identified in the high HbF patient cohort that may contribute to milder phenotypes in African Americans. To complement the SNP studies, genome wide microRNA (miRNA) data was generated which showed increased miR‐16 levels associated with high HbF. Furthermore, MYB, the negative regulator of γ‐globin expression, is silenced by miR‐16 through binding the 3′‐untranslated region. RT‐qPCR and western blot were used to measure γ‐globin mRNA and HbF protein levels respectively after transfection of miR‐16 mimic into KU812 cells. Preliminary data revealed dose dependent miR‐16 mediated MYB suppression and γ‐globin activation. The discovery of regulatory regions that modulate HbF expression and miRNA mediated suppression of negative regulators of γ‐globin, provides expanded understanding of gene regulation, which can be used to define novel treatment options for individuals with SCD.Support or Funding InformationSponsored by the Medical College of Georgia Medical Scholars Program
A Reductionist Approach to Understanding Membrane Fusion
Authors: Wickner William T. 
Published: November 2023

Membrane fusion is essential for intracellular protein targeting, cell growth, neurotransmission, and hormone secretion. Since the mechanism of fusion is conserved from yeast to humans, we study fusion of the vacuole (lysosome) of the biochemically and genetically tractable yeast S. cerervisiae. Vacuole fusion requires phosphoinositides and non‐bilayer‐prone lipids, a Rab family GTPase, four SNARE proteins which form complexes together in cis (bound to the same membrane) or trans (bound to apposed membranes before fusion), the SNARE complex disassembly chaperone Sec18 (NSF), its cochaperone and fusion‐trigger protein Sec17, and a large, multisubunit complex termed HOPS (homotypic fusion and vacuole protein sorting). HOPS binds two membrane‐anchored Rabs to tether the organelle, catalyzes trans‐SNARE complex assembly through its Sec1/Munc18 (SM)‐homolog subunit, and directly associates with acidic lipids and phosphoinositides.Each of these factors has been shown through genetics to be required for fusion in vivo, and in vitro for fusion of the isolated organelle. To understand the mechanism, we have reconstituted fusion with each of these purified, recombinant proteins and 8 defined lipids, revealing novel aspects of membrane fusion: 1. The lipid bilayer isn't just a passive player. Acidic lipids, non‐bilayer prone lipids, phosphoinositides, and the fluidity of the fatty acyl phase are each crucial. 2. Tethering is an essential step for fusion, even where trans‐SNARE complexes have formed. 3. SNARE complex assembly is catalyzed by SM proteins and associated proteins, 4. Sec17 (a‐SNAP) binds to the trans‐SNARE complex and inserts an apolar loop into the bilayer to trigger fusion. 5. A supercomplex of HOPS with trans‐SNARE complexes is found on the purified vacuole and can be reconstituted with purified components; we are seeking its precise function in the fusion cascade.Support or Funding InformationThis work was supported by NIH grant GM23377‐40
Kinesiological benefits of botulinum toxin type A combined with exercise on the functional recovery after spinal cord injury
Authors: Jin Yunho , Park Sookyoung , Hong Yonggeun 
Published: November 2023

Spinal cord injury (SCI) is a result of a traumatic damage of the vertebral column. This injury interrupts the signal conduction from upper motor neuron to lower motor neuron and spasticity may occur. Spasticity is common motor dysfunction induced from upper motor neuron lesions. Botulinum toxin type A (BTA) can inhibit muscle contraction as well as acetylcholine release by without affection to acetylcholine synthesis. Treadmill exercise (Ex) is known to reduce body and fat mass resulting improvement of neuroplasticity. Therefore, the purpose of this study was to evaluate the effect of BTA combined with treadmill exercise after SCI. Experimental animals were divided into three groups; SCI, SCI+BTA, SCI+BTA+Ex. BTA was injected into the gastrocnemius of SCI+BTA and SCI+BTA+Ex rats. And, SCI+BTA+Ex rats were assigned to treadmill exercise. After 14 postoperative day, all animals were sacrificed to perform further analyses. SCI+BTA+Ex group showed the lowest mass of body weight and gastrocnemius which muscle subjected to injection of BTA directly. However, they showed the highest motor functioning scores. In addition, by light microscopy, several vacuoles were observed in the muscle fibers of SCI group rats, indicating delayed functional recovery. In this study, BTA is thought to have slight spasticity‐alleviating effect, and this effect is extended by combination of treadmill exercise.Support or Funding InformationFunds: NRF‐2013R1A2A2A01067169 to Y.H., 2014R1A1A3051724 to S.P., KRIBB Research Initiative Program (KGM4611613 to Y.H.), Republic of Korea.
The immunomodulatory properties of adipose mesenchymal stem cell‐derived exosomes are induced by inflammatory cytokines
Authors: Domenis Rossana , Quaglia Sara , Cifù Adriana , Pistis Cinzia , Fabris Martina , Moretti Massimo , Vicario Annalisa , Niazi Kayvan R. , Curcio Francesco 
Published: November 2023

IntroductionThe predominant mechanism by which adipose mesenchymal stem cells (AMSCs) participate to tissue repair is through a paracrine activity and their communication with the inflammatory microenvironment is essential part of this process. This hypothesis has been strengthened by the recent discovery that stem cells release not only soluble factors but also extracellular vesicles, which elicit similar biological activity to the stem cells themselves. The most prominent of the extracellular vesicles are exosomes, that through the delivery and the transfer of protein, bio‐active lipid and nucleic acid cargo, are able to induce phenotypic and functional changes in the recipient cells that promote the activation of regenerative programs. The purpose of this study is to investigate the immunomodulatory properties of exosomes released from AMSCs under stimulation with inflammatory cytokines.MethodsAMSCs were treated with different concentration of INFγ+TNFα for 48h and then proliferation/viability was measured by trypan blue exclusion count, expression of IDO enzyme was evaluated by flow cytometry and release of PGE2 by ELISA. Exosomes were isolated from AMSCs supernatants by polymer precipitation method (Exoquick). To evaluate their immune‐regulatory properties, CD14+ monocytes were treated, during their differentiation into M1 macrophages, with AMSCs‐derived exosomes. After treatment, macrophages were characterized for the expression of CD80 (M1 expression marker) or CD163 (M2 expression marker) by flow cytometry.ResultsPro‐inflammatory INFγ+TNFα cytokines decreased AMSCs proliferation rate, while viability was not affected, and increased the expression of the immunosuppressive IDO enzyme and the release of PGE2 in dose‐dependent manner. Only exosomes released from cytokines‐treated cells were able to significantly reverse the M1 phenotype of macrophages indicating a polarization towards the M2 phenotype.ConclusionsThe treatment with inflammatory cytokines increase the immunosuppressive and anti‐inflammatory potential of AMSCs‐derived exosomes, which became able to shift macrophages from M1 to M2 phenotype. This suggests that the immunomodulatory properties of AMSCs‐derived exosomes may be not constitutive but are instead induced by the inflammatory microenvironment.
Ethnic variations in mercury exposure from seafood consumption and the risk of Kawasaki disease in young children
Authors: Portman Michael A. , Yeter Deniz , Kuo Ho‐Chang 
Published: November 2023

Kawasaki disease (KD) is an acute febrile illness predominately affecting children <5 years that can result in serious cardiovascular complications such as coronary artery lesion formation. The cause of KD remains unknown 50 years after Kawasaki first described the illness in Japan, while KD has since replaced rheumatic fever as the leading cause of acquired heart disease for children in the developed world. KD has become the most commonly diagnosed pediatric vasculitis with the highest incidence rates of KD reported from East Asian countries such as Japan, Korea, and Taiwan. Even when residing in Western nations, East Asian children still have 10 to 20 times the risk of developing KD than children of other ethnicities. Speculation that genetic differences between ethnic groups account for the ethnic disparity in KD rates led to the discovery and confirmation of numerous susceptibility loci, although these risk alleles only appear to confer risk passively to the currently unknown environmental triggers of KD. Previously, we described how ITPKC susceptibility in KD patients would render these individuals vulnerable to mercury (Hg)‐induced autoimmunity through the induction of intracellular calcium release with downstream effects upon cell signaling, immune proliferation, and gene expression via the Ca2+/NFAT pathway. This led us to hypothesize that the ethnic disparities in KD risk may be accounted for by variations in Hg exposure rates, particularly from significant differences in total methylmercury (MeHg) intake from seafood. We examined two separate cohorts that were nationally representative of either KD hospitalization rates or toxic metal concentrations in the blood in our initial investigations. Our results demonstrated that increasing ethnic KD risk between Caucasian, Hispanic, Black, and Asian children was significantly associated with average blood levels and detection rates of Hg or cadmium (Cd) but not lead (Pb), manganese (Mn), or selenium (Se). In our most recent investigations using the same two datasets, we observed that ethnic KD risk was significantly associated with increasing consumption of total fish and seafood but not shellfish. Further examinations by Hg type demonstrated that MeHg from seafood is the primary source of blood Hg in children, while average blood MeHg levels but not inorganic or ethylmercury were significantly associated with increasing ethnic KD risk. Lastly, ethnic KD risk was significantly associated with molar ratios of Hg and Se in the blood that are indicative of seafood consumption. We conclude that Hg exposure particularly from seafood consumption may increase susceptibility for the development of KD in young children or trigger the disease, itself. However, our hypothesis requires determinations of blood Hg levels and cumulative Hg exposure such as from dietary seafood intake in KD patients, which are currently lacking and that we are presently examining.Support or Funding InformationNone
Quantitative Image Analysis of Traumatic Brain Injury Induced Aspiration Pneumonia Treatment
Authors: Howell Cody C. , Sandusky George E. 
Published: November 2023

Infection of the patient is one of the greatest risks inherent to surgical transplants. While great effort is taken to minimize this risk; variables outside of surgeon control can still result in transference of disease from donor to patient. Such conditions are common in lung transplants from donors having suffered traumatic brain injury (TBI). Autonomic nervous system damage from injury prior to transplant can result in involuntary intake of food into the lungs, developing into aspiration pneumonia. Remaining undetected until complications arise in the recipient. This study evaluated TBI model mice treated with simulated transplant conditions. The control groups included: aspiration pneumonia, aspiration treated with phosphate buffered saline (PBS), TBI without aspiration, TBI with aspiration and no treatment, TBI with PBS, TBI with aspiration treated with PBS. Drug treatment groups of TBI with aspiration pneumonia were dosed with either BB5, or a proprietary complement inhibitor.Mouse lung tissue was removed and fixed in 10% neutral buffered formalin (10% NBF) for 24 hours, processed into a paraffin block, cut via microtome and H&E stained. Slides were then examined and whole slide digital images were created and evaluated using quantitative imaging software. The software utilized for calculating the percentage of inflammatory cellular infiltrates across the groups used Red‐Green‐Blue color algorithms to classify stained tissue slides. Initial analysis with Aperio Imagescope was unable to classify the color difference between similarly stained inflammatory cells and alveoli septa in the lungs. Indica Lab's HALO software was used for the second round of analysis. Both drug treatment groups were determined to have a biologically significant reduction in aspiration pneumonia compared to the control groups in both analysis systems. Indica Labs' HALO software was more specific in differentiating inflammatory cells in this difficult analysis.
High‐precision pharmacokinetic measurements in anesthetized and awake behaving animals
Authors: Vieira Philip A. , Arroyo Netz , Shin Christina , Ploense Kyle , Plaxco Kevin , Kippin Tod 
Published: November 2023

ObjectiveThe development of technology capable of tracking the in vivo levels of drugs, metabolites, and biomarkers continuously and in real‐time would revolutionize our understanding of health and our ability to detect and treat disease. It would, for example, enable therapies guided by patient‐specific real‐time pharmacokinetics, opening a new dimension in personalized medicine.MethodsIn response we demonstrate here the ability of electrochemical aptamer‐based (E‐AB) sensors to support such measurements in vivo in living subjects.ResultsSpecifically, we have used E‐AB sensors to perform multi‐hour measurements of specific molecules in the bloodstream of anesthetized and even awake, ambulatory rats, achieving clinically relevant detection limits, low‐ to sub‐micromolar precision, and second‐scale time resolution.ConclusionThis work demonstrates the use of E‐AB sensors as a viable option for fast, real‐time measurement of drug targets as they interact with the body, suggesting the approach may prove a powerful new tool for the study of physiology, pharmacokinetics and pathology through the measurement of relevant biomarkers in conjunction with treatment.Support or Funding InformationW.M. Keck Foundation
Circulating Concentrations of GDF8, but not GDF11, are Heritable when Evaluated by LC‐MS/MS
Authors: Bumgardner Sara A , Pazdro Robert 
Published: November 2023

Growth differentiation factor 11 (GDF11) and GDF8/myostatin exhibit a high level of homology within their mature, active protein domains, which has led to a considerable degree of conflicting data. We previously demonstrated a high degree of narrow‐sense heritability for circulating GDF11 in mice utilizing antibody‐based methodologies, which correlated with and predicted the median lifespan of mice. In order to validate this data, we evaluated both serum GDF11 and GDF8/myostatin across four young‐adult mouse strains via LC‐MS/MS. We were unable to corroborate the narrow‐sense heritability of GDF11, but instead found that GDF8/myostatin is highly heritable and represents a large portion of the serum GDF11/8 phenotype. Additionally, the concentration of GDF11 as measured by LC‐MS/MS was significantly greater than that identified through antibody‐based methods. We hypothesize that these discrepancies could be due to variable assay specificity for total, latently‐bound, or active protein forms and/or assay sensitivity. Further research is needed to clarify the functional role and effect of natural genetic variation on circulating GDF11 and GDF8/myostatin.Support or Funding InformationResearch was funded by the University of Georgia Office of the Vice President for Research.
Kappa Opioid Receptor Signaling Contributes to Re‐escalation of Oxycodone Self‐administration Under Extended Access Conditions
Authors: Nguyen Jacques D , Kirson Dean , Grant Yanabel , Varodayan Florence P , Khom Sophia , Patel Reesha , Hedges David M , Roberto Marisa , Taffe Michael A 
Published: November 2023

Prescription opioid abuse is a significant global problem, and opioid addiction is well‐characterized by compulsive drug seeking, motivational withdrawal and chronic relapse. The goal of this study was to investigate escalation of opioid intake with extended access to intravenous oxycodone self‐administration and re‐engagement of drug seeking (re‐escalation) following detoxification. Male Wistar rats were randomly assigned to short‐access (ShA, 1‐h) and long‐access (LgA, 12‐h) groups and trained to self‐administer oxycodone (0.15 mg/kg/infusion) using a fixed‐ratio 1 (FR1) response contingency and evaluated on a progressive‐ratio (PR) procedure incorporating dose‐substitution of oxycodone (0.06–0.3 mg/kg/infusion). Both groups underwent an abstinence period (4 weeks) and were tested for re‐escalation. Rats given LgA to oxycodone earned more infusions than rats trained with ShA during acquisition. PR test results demonstrated an increase in drug‐intake and breakpoints in rats assigned to LgA training relative to rats assigned to ShA training. All rats exhibited high levels of drug seeking upon re‐engagement; however, LgA rats failed to de‐escalate drug intake following the abstinence period. Previous findings show kappa opioid receptor (KOR) mediated disruption in GABAergic signaling in the central nucleus of the amygdala (CeA) is observed after acute (24‐h) withdrawal from escalated cocaine self‐administration. To investigate KOR dysregulation following acute oxycodone withdrawal, electrophysiological recordings were performed in CeA slices. The selective KOR agonist U‐50488 decreased GABAergic signaling in both ShA and LgA rats, and this effect was blocked by KOR antagonist nor‐binaltorphimine (nor‐BNI). Applied alone, norBNI increased GABAergic signaling, suggesting tonic KOR activity. These findings further support the conclusion that access duration differentially impacts the acquisition and maintenance of the self‐administration of oxycodone, and suggest that KOR‐mediated signaling during oxycodone dependence may be distinct from that of other drugs of abuse.Support or Funding InformationNIH grant DA035281