Digital Commons Network^™

Hyperkalemia: Pharmacotherapies And Clinical Considerations, Evan S. Sinnathamby, Kelly T. Banh, William T. Barham, Tyler D. Hernandez, Audrey J. De Witt, Danielle M. Wenger, Vincent G. Klapper, David Mcgregor, Antonella Paladini, Shahab Ahmadzadeh, Sahar Shekoohi, Alan D. Kaye, Giustino Varrassi

School of Medicine Faculty Publications

Hyperkalemia has been defined as a condition where a serum potassium level is > 5.5 mmol/l. It is associated with fatal dysrhythmias and muscular dysfunction. Certain medical conditions, such as chronic kidney disease (CKD), diabetes mellitus, and others, can lead to hyperkalemia. Many of the signs of hyperkalemia are nonspecific. A history and physical examination can be beneficial in the diagnosis of the condition. In this regard, certain characteristic electrocardiogram findings are associated with hyperkalemia along with laboratory potassium levels. In acute and potentially lethal conditions, hyperkalemia treatments include glucose and insulin, bicarbonate, calcium gluconate, beta-2 agonists, hyperventilation, and dialysis. There …

Kv12-Encoded K+ Channels Drive The Day-Night Switch In The Repetitive Firing Rates Of Scn Neurons, Tracey O Hermanstyne, Nien-Du Yang, Daniel Granados-Fuentes, Xiaofan Li, Rebecca L Mellor, Timothy Jegla, Erik D Herzog, Jeanne M Nerbonne

2020-Current year OA Pubs

Considerable evidence suggests that day-night rhythms in the functional expression of subthreshold potassium (K+) channels regulate daily oscillations in the spontaneous firing rates of neurons in the suprachiasmatic nucleus (SCN), the master circadian pacemaker in mammals. The K+ conductance(s) driving these daily rhythms in the repetitive firing rates of SCN neurons, however, have not been identified. To test the hypothesis that subthreshold Kv12.1/Kv12.2-encoded K+ channels play a role, we obtained current-clamp recordings from SCN neurons in slices prepared from adult mice harboring targeted disruptions in the Kcnh8 (Kv12.1-/-) or Kcnh3 (Kv12.2-/-) locus. We found that mean nighttime repetitive firing rates …

Membrane Phospholipids Control Gating Of The Mechanosensitive Potassium Leak Channel Trek1, Philipp A M Schmidpeter, John T Petroff 2nd, Leila Khajoueinejad, Aboubacar Wague, Cheryl Frankfater, Wayland W L Cheng, Crina M Nimigean, Paul M Riegelhaupt

2020-Current year OA Pubs

Tandem pore domain (K2P) potassium channels modulate resting membrane potentials and shape cellular excitability. For the mechanosensitive subfamily of K2Ps, the composition of phospholipids within the bilayer strongly influences channel activity. To examine the molecular details of K2P lipid modulation, we solved cryo-EM structures of the TREK1 K2P channel bound to either the anionic lipid phosphatidic acid (PA) or the zwitterionic lipid phosphatidylethanolamine (PE). At the extracellular face of TREK1, a PA lipid inserts its hydrocarbon tail into a pocket behind the selectivity filter, causing a structural rearrangement that recapitulates mutations and pharmacology known to activate TREK1. At the cytoplasmic …

Wayne E. Sabbe Arkansas Soil Fertility Studies 2022, Nathan A. Slaton, Mike Daniels

Arkansas Agricultural Experiment Station Research Series

Rapid technological changes in crop management and production require that the research efforts be presented in an expeditious manner. The contributions of soil fertility and fertilizers are major production factors in all Arkansas crops. The studies described within will allow producers to compare their practices with the university’s research efforts. Additionally, soil-test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.

Conformational Plasticity Of Nak2k And Trek2 Potassium Channel Selectivity Filters, Marcos Matamoros, Xue Wen Ng, Joshua B Brettmann, David W Piston, Colin G Nichols

2020-Current year OA Pubs

The K

Hyperkalemia And Electrocardiogram Manifestations In End-Stage Renal Disease, Zubaid Rafique, Bryan Hoang, Heba Mesbah, Ryan Pappal, Frank W Peacock, Raul Juarez-Vela, Lukasz Szarpak, Dick C Kuo

2020-Current year OA Pubs

Hyperkalemia is one of the more common acute life-threatening metabolic emergencies. The aim of our study is to determine the correlation and accuracy of abnormal ECG parameters as a function of serum potassium concentration in the end-stage renal disease (ESRD) population. We performed a retrospective chart review of emergency department patients presenting with ESRD and receiving emergent hemodialysis treatment. A total of 96 patients, each with five independent ED visits, provided 480 sets of ECGs and electrolytes. Of these, four ECGs were excluded for inability to interpret, leaving a total of 476 patient encounters that met all inclusion criteria. Linear …

Structural Basis For Mechanotransduction In A Potassium-Dependent Mechanosensitive Ion Channel, Jonathan Mount, Grigory Maksaev, Brock T Summers, James A J Fitzpatrick, Peng Yuan

2020-Current year OA Pubs

Mechanosensitive channels of small conductance, found in many living organisms, open under elevated membrane tension and thus play crucial roles in biological response to mechanical stress. Amongst these channels, MscK is unique in that its activation also requires external potassium ions. To better understand this dual gating mechanism by force and ligand, we elucidate distinct structures of MscK along the gating cycle using cryo-electron microscopy. The heptameric channel comprises three layers: a cytoplasmic domain, a periplasmic gating ring, and a markedly curved transmembrane domain that flattens and expands upon channel opening, which is accompanied by dilation of the periplasmic ring. …

Sars-Cov-Ate Risk Assessment Model For Arterial Thromboembolism In Covid-19, Pin Li, Yi Lee, Qasim Jehangir, Chun-Hui Lin, Geetha Krishnamoorthy, Anupam A. Sule, Abdul R. Halabi, Kiritkumar Patel, Laila M. Poisson, Girish B. Nair

Public Health Sciences Articles

Patients with SARS-CoV-2 infection are at an increased risk of cardiovascular and thrombotic complications conferring an extremely poor prognosis. COVID-19 infection is known to be an independent risk factor for acute ischemic stroke and myocardial infarction (MI). We developed a risk assessment model (RAM) to stratify hospitalized COVID-19 patients for arterial thromboembolism (ATE). This multicenter, retrospective study included adult COVID-19 patients admitted between 3/1/2020 and 9/5/2021. Among 3531 patients from the training cohort, 15.5% developed acute in-hospital ATE, including stroke, MI, and other ATE, compared to 13.4% in the validation cohort. The 16-item final score was named SARS-COV-ATE (Sex: male …

Wayne E. Sabbe Arkansas Soil Fertility Studies 2021, Nathan A. Slaton

Arkansas Agricultural Experiment Station Research Series

Rapid technological changes in crop management and production require that the research efforts be presented in an expeditious manner. The contributions of soil fertility and fertilizers are major production factors in all Arkansas crops. The studies described within will allow producers to compare their practices with the university’s research efforts. Additionally, soil-test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.

Chloride Sensing By Wnk1 Regulates Nlrp3 Inflammasome Activation And Pyroptosis., Lindsey Mayes-Hopfinger, Aura Enache, Jian Xie, Chou-Long Huang, Robert Köchl, Victor L.J. Tybulewicz, Teresa Fernandes-Alnemri, Emad S. Alnemri

Department of Biochemistry and Molecular Biology Faculty Papers

The NLRP3 inflammasome mediates the production of proinflammatory cytokines and initiates inflammatory cell death. Although NLRP3 is essential for innate immunity, aberrant NLRP3 inflammasome activation contributes to a wide variety of inflammatory diseases. Understanding the pathways that control NLRP3 activation will help develop strategies to treat these diseases. Here we identify WNK1 as a negative regulator of the NLRP3 inflammasome. Macrophages deficient in WNK1 protein or kinase activity have increased NLRP3 activation and pyroptosis compared with control macrophages. Mice with conditional knockout of WNK1 in macrophages have increased IL-1β production in response to NLRP3 stimulation compared with control mice. Mechanistically, …

Evaluation Of Serum Magnesium Differences In Hypertensive Crises And Control Patients: A Randomly Matched Case-Control Study, Ifeanyi Chukwu O. Onor, Emily K. Johnston, Nicole G. Little, Lashira M. Hill, Oluwabunmi E. Lawal, Casey J. Payne, Mallory R. Coleman, Carolkim H. Huynh, Sarah E. Bilbe, Ahlam A. Ayyad, Kabrea J. Jones, Jasmine D. Kinnard, Rosanna Dastoori, Devinn K. Rolland, Amanda S. Miller, Robbie A. Beyl, Christopher J. Gillard, John I. Okogbaa, Daniel F. Sarpong, Rim M. Hadgu, Amne Borghol, Samuel C. Okpechi, Mihran V. Naljayan, Shane E. Sanno, Shane G. Guillory

School of Medicine Faculty Publications

Although the role of magnesium in blood pressure has been well studied among hypertensive patients, no study has explored the role of magnesium in hypertensive crises. The primary objective of this study is to evaluate the differences in serum magnesium levels between hypertensive crises patients and matched controls (age-, sex-, race-, and diabetes-matched) in a 1:1 random match. This study is a single-center, retrospective, chart review, case-control study of patients with hypertensive crises (case group) and patients without hypertensive crises (control group). Patients were included in the case group if they were 18 years of age or older with hypertensive …

The Dietary Management Of Potassium In Children With Ckd Stages 2-5 And On Dialysis-Clinical Practice Recommendations From The Pediatric Renal Nutrition Taskforce., An Desloovere, José Renken-Terhaerdt, Jetta Tuokkola, Vanessa Shaw, Larry A. Greenbaum, Dieter Haffner, Caroline Anderson, Christina L. Nelms, Michiel J S Oosterveld, Fabio Paglialonga, Nonnie Polderman, Leila Qizalbash, Bradley A. Warady, Rukshana Shroff, Johan Vande Walle

Manuscripts, Articles, Book Chapters and Other Papers

Dyskalemias are often seen in children with chronic kidney disease (CKD). While hyperkalemia is common, with an increasing prevalence as glomerular filtration rate declines, hypokalemia may also occur, particularly in children with renal tubular disorders and those on intensive dialysis regimens. Dietary assessment and adjustment of potassium intake is critically important in children with CKD as hyperkalemia can be life-threatening. Manipulation of dietary potassium can be challenging as it may affect the intake of other nutrients and reduce palatability. The Pediatric Renal Nutrition Taskforce (PRNT), an international team of pediatric renal dietitians and pediatric nephrologists, has developed clinical practice recommendations …

Forage News [2021-03], Department Of Plant And Soil Sciences, University Of Kentucky

Forage News

No abstract provided.

Wayne E. Sabbe Arkansas Soil Fertility Studies 2020, Nathan A. Slaton

Arkansas Agricultural Experiment Station Research Series

Rapid technological changes in crop management and production require that the research efforts be presented in an expeditious manner. The contributions of soil fertility and fertilizers are major production factors in all Arkansas crops. The studies described within will allow producers to compare their practices with the university’s research efforts. Additionally, soil-test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.

Despite Increasing Aldosterone, Elevated Potassium Is Not Necessary For Activating Aldosterone-Sensitive Hsd2 Neurons Or Sodium Appetite, Frederico S Fazan, Eduardo Colombari, Arthur D Loewy, Joel C Geerling

Open Access Publications

Restricting dietary sodium promotes sodium appetite in rats. Prolonged sodium restriction increases plasma potassium (pK), and elevated pK is largely responsible for a concurrent increase in aldosterone, which helps promote sodium appetite. In addition to increasing aldosterone, we hypothesized that elevated potassium directly influences the brain to promote sodium appetite. To test this, we restricted dietary potassium in sodium-deprived rats. Potassium restriction reduced pK and blunted the increase in aldosterone caused by sodium deprivation, but did not prevent sodium appetite or the activation of aldosterone-sensitive HSD2 neurons. Conversely, supplementing potassium in sodium-deprived rats increased pK and aldosterone, but did not …

K2p2.1 (Trek-1) Potassium Channel Activation Protects Against Hyperoxia-Induced Lung Injury, Tatiana Zyrianova, Benjamin Lopez, Riccardo Olcese, John Belperio, Christopher M. Waters, Leanne Wong, Victoria Nguyen, Sriharsha Talapaneni, Andreas Schwingshackl

Physiology Faculty Publications

No targeted therapies exist to counteract Hyperoxia (HO)-induced Acute Lung Injury (HALI). We previously found that HO downregulates alveolar K_2P2.1 (TREK-1) K⁺ channels, which results in worsening lung injury. This decrease in TREK-1 levels leaves a subset of channels amendable to pharmacological intervention. Therefore, we hypothesized that TREK-1 activation protects against HALI. We treated HO-exposed mice and primary alveolar epithelial cells (AECs) with the novel TREK-1 activators ML335 and BL1249, and quantified physiological, histological, and biochemical lung injury markers. We determined the effects of these drugs on epithelial TREK-1 currents, plasma membrane potential (Em), and intracellular Ca …

Crystal Structures Of Two Isostructural Compounds: A Second Polymorph Of Dipotassium Hydrogen Citrate, K2hc6h5o7, And Potassium Rubidium Hydrogen Citrate, Krbhc6h5o7, Diana Gonzalez '20, Joseph T. Golab, Andrew J. Cigler, James A. Kaduk

Student Publications & Research

No abstract provided.

Estimates Of Sodium And Potassium Intake And Their Molar Ratio In Irish Children: Preliminary Findings From Ncfsii, Eoin James Morrissey, Laura Kehoe, Aoibhin Moore Heslin, Maria Buffini, Breige Mcnulty, Anne Nugent, John Kearney, Albert Flynn, Janette Walton

Department of Biological Sciences Publications

The Food Safety Authority of Ireland (FSAI) have set target maximum daily salt intakes for children (4–6y: 3 g, 7–10y: 5 g, 11–14y: 6g) while the European Food Safety Authority (EFSA) have set Adequate Intakes (AI) for potassium of 1100mg/d, 1800mg/d and 2700mg/d for children of the same respective age groups. An individual’s sodium to potassium (Na:K) intake ratio is an important predictor of hypertension and the World Health Organization (WHO) recommend a Na:K intake ratio of ≤ 1.0mmol/mmol for both adults and children. Although the morbidities associated with hypertension may not be seen until adulthood, blood pressure in childhood …

Wayne E. Sabbe Arkansas Soil Fertility Studies 2019, Nathan A. Slaton

Arkansas Agricultural Experiment Station Research Series

Rapid technological changes in crop management and production require that the research efforts be presented in an expeditious manner. The contributions of soil fertility and fertilizers are major production factors in all Arkansas crops. The studies described within will allow producers to compare their practices with the university’s research efforts. Additionally, soil-test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.

Sodium And Potassium Intakes And Their Ratio In Adults (18–90 Y): Findings From The Irish National Adult Nutrition Survey, Eoin James Morrissey, Miriam Giltinan, Laura Kehoe, Anne P. Nugent, Breige A. Mcnulty, Albert Flynn, Janette Walton

Department of Biological Sciences Publications

An individual’s sodium to potassium intake ratio (Na:K) has been shown to be an important predictor of hypertension. The aim of this study was to estimate the mean 24 h urinary Na, K and Na:K of Irish adults and to identify the foods that determine Na:K in a nationally representative sample of Irish adults. This study was based on data from the Irish National Adult Nutrition Survey (2008–2010) (NANS), which collected spot urine samples and dietary data in a nationally representative sample of Irish adults aged 18+ years. The mean urinary molar Na:K of Irish men and women was 1.90 …

Effects Of Caffeine On Neuromuscular Function In A Non-Fatigued State And During Fatiguing Exercise, Ricardo N. O. Mesquita, Neil J. Cronin, Heikki Kyröläinen, Jukka Hintikka, Janne Avela

Research outputs 2014 to 2021

New Findings:

What is the central question of the study? What are the effects of caffeine on neuromuscular function in a non-fatigued state and during fatiguing exercise? What is the main finding and its importance? In a non-fatigued state, caffeine decreased the duration of the silent period evoked by transcranial magnetic stimulation. Caffeine-induced reduction of inhibitory mechanisms in the central nervous system before exercise was associated with an increased performance. Individuals who benefit from caffeine ingestion may experience lower perception of effort during exercise and an accelerated recovery of M-wave amplitude postfatigue. This study elucidates the mechanisms of action of …

Using Electrolyte Repletion Guidelines To Improve The Rate Of Oral Potassium And Magnesium Delivery, Joshua Riley, Alan Kubey, Md

Phase 1

Introduction: Evidence-based guidelines for electrolyte replacement that safely encourage oral (PO) and/or intravenous (IV) dosing more successfully attain goal levels than standard care. However, the Thomas Jefferson University Hospital (TJUH) electrolyte replacement guidelines (JG 11-1296), approved in 2002 and last updated in 2008, provide guidance for IV repletion not PO. Between 5/2017-11/2017, TJUH dosed potassium and magnesium in a 2.30 and 4.24 IV:PO ratio, respectively. If 50% of doses were given PO, we anticipate ~$800,000 annual TJUH savings.

Methods: We created a multidisciplinary team and completed a literature review to inform the creation of updated TJUH guidelines for …

Altered Gating Of KV1.4 In The Nucleus Accumbens Suppresses Motivation For Reward, Bernadette O'Donovan, Adewale Adeluyi, Erin L Anderson, Robert D. Cole, Jill R. Turner, Pavel I. Ortinski

Neuroscience Faculty Publications

Deficient motivation contributes to numerous psychiatric disorders, including withdrawal from drug use, depression, schizophrenia, and others. Nucleus accumbens (NAc) has been implicated in motivated behavior, but it remains unclear whether motivational drive is linked to discrete neurobiological mechanisms within the NAc. To examine this, we profiled cohorts of Sprague-Dawley rats in a test of motivation to consume sucrose. We found that substantial variability in willingness to exert effort for reward was not associated with operant responding under low-effort conditions or stress levels. Instead, effort-based motivation was mirrored by a divergent NAc shell transcriptome with differential regulation at potassium and dopamine …

Urinary Ratio Of Sodium And Potassium In Irish Adults, Eoin James Morrissey, M. Giltinan, L. Kehoe, A. P. Nugent, B. Mcnulty, A. Flynn, Janette Walton

Department of Biological Sciences Publications

Cardiovascular Disease (CVD) is one of the leading causes of morbidity and mortality in the world accounting for approximately one third of global deaths. A diet low in sodium (Na) and high in potassium (K) is widely recommended as a strategy to lower blood pressure and to reduce the risk of CVD. The independent roles that both sodium and potassium play in blood pressure have been long established, however in recent times increasing evidence has suggested that an individual’s Na:K ratio is a more important predictor of hypertension than either sodium or potassium intake alone. The Food Safety Authority of …

Water Intake After Dehydration Makes Muscles More Susceptible To Cramp But Electrolytes Reverse That Effect, Wing Yin Lau, Haruyasu Kato, Kazunori Nosaka

Research outputs 2014 to 2021

Objective No previous study has compared water and oral rehydration solution (ORS) intake after dehydration induced by exercise in the heat for the effect on muscle cramps. The present study tested the hypothesis that water ingestion after dehydration would increase muscle cramp susceptibility, but this would be prevented by ORS ingestion. Methods Ten men performed two bouts of downhill running (DHR; -5%) in the heat (35°C-36 °C) until their body mass was reduced by 2%. Ten minutes after DHR, either spring water or electrolyte water similar to ORS (OS-1 ®) was ingested in a counter-balanced order on two different days …

Macronutrients In Soil And Wheat As Affected By A Long-Term Tillage And Nitrogen Fertilization In Winter Wheat-Fallow Rotation, Santosh Shiwakoti, Valtcho D. Zheljazkov, Hero T. Gollany, Baoshan Xing

Stockbridge Faculty Publication Series

The insights gained from the long-term impacts of tillage and N fertilization on soil fertility are crucial for the development of sustainable cropping systems. The objectives of this study were to quantify the effects of 75 years of tillage and N fertilization on macronutrients in soil and wheat (Triticum aestivum L.) tissues grown in a winter wheat–summer fallow rotation. The experiment included three types of tillage (disc, DP; sweep, SW; and moldboard, MP) and five N application rates (0, 45, 90, 135, and 180 kg ha⁻¹). Soil and tissue samples were analyzed for the concentration of total N, …

The Effect Of Flinak Molten Salt Corrosion On The Hardness Of Hastelloy N, David Kok

Honors Program Projects

The desire to reduce pollution caused by electricity production has led to a call for the replacement of conventional fossil fuel power plants. In order to fulfill this goal, a large amount of new nuclear reactors is required, and this provides the opportunity to put new and innovative reactor designs into production. The Molten Salt Reactor (MSR) is one of the most promising concepts, but a suitable combination of molten salt and container material needs to be found to reduce the potential for corrosion before the concept can be put into production. FLiNaK molten salt and the nickel-based alloy Hastelloy …

A Xenopus Oocyte Model System To Study Action Potentials, Aaron Corbin-Leftwich, Hannah E Small, Helen H Robinson, Carlos A. Villalba-Galea, Linda M Boland

School of Pharmacy Faculty Articles

Action potentials (APs) are the functional units of fast electrical signaling in excitable cells. The upstroke and downstroke of an AP is generated by the competing and asynchronous action of Na+- and K+-selective voltage-gated conductances. Although a mixture of voltage-gated channels has been long recognized to contribute to the generation and temporal characteristics of the AP, understanding how each of these proteins function and are regulated during electrical signaling remains the subject of intense research. AP properties vary among different cellular types because of the expression diversity, subcellular location, and modulation of ion channels. These complexities, in addition to the …

Translational Evaluation Of Acid/Base And Electrolyte Alterations In Rodent Model Of Focal Ischemia, Sarah R. Martha, Lisa A. Collier, Stephanie M. Davis, Hilary A. Seifert, Christopher C. Leonardo, Craig T. Ajmo, Elspeth A. Foran, Justin F. Fraser, Keith R. Pennypacker

Neurology Faculty Publications

BACKGROUND AND PURPOSE: Acid/base and electrolytes could provide clinically valuable information about cerebral infarct core and penumbra. We evaluated associations between acid/base and electrolyte changes and outcomes in 2 rat models of stroke, permanent, and transient middle cerebral artery occlusion.

METHODS: Three-month old Sprague-Dawley rats underwent permanent or transient middle cerebral artery occlusion. Pre- and post-middle cerebral artery occlusion venous samples for permanent and transient models provided pH, carbon dioxide, oxygen, glucose, and electrolyte values of ionized calcium, potassium, and sodium. Multiple regression determined predictors of infarct volume from these values, and Kaplan-Meier curve analyzed morality between permanent and transient …

Phosphorus And Potassium Fertilizer Application Strategies In Corn–Soybean Rotations, Timothy J. Boring, Kurt D. Thelen, James E. Board, Jason L. De Bruin, Chad D. Lee, Seth L. Naeve, William J. Ross, Wade A. Kent, Landon L. Ries

Plant and Soil Sciences Faculty Publications

To determine if current university fertilizer rate and timing recommendations pose a limitation to high-yield corn (Zea mays subsp. mays) and soybean (Glycine max) production, this study compared annual Phosphorous (P) and Potassium (K) fertilizer applications to biennial fertilizer applications, applied at 1× and 2× recommended rates in corn–soybean rotations located in Minnesota (MN), Iowa (IA), Michigan (MI), Arkansas (AR), and Louisiana (LA). At locations with either soil test P or K in the sub-optimal range, corn grain yield was significantly increased with fertilizer application at five of sixteen site years, while soybean seed yield was significantly …