Search results for "Potassium"

showing 10 items of 930 documents

Modeling ATP protonation and activity coefficients in NaClaq and KClaq by SIT and Pitzer equations.

2006

Abstract The acid–base properties of Adenosine 5′-triphosphate (ATP) in NaCl and KCl aqueous solutions at different ionic strengths (0  I  / mol L − 1  ≤ 5 for NaCl aq , 0  I  / mol L − 1  ≤ 3 for KCl aq ) and at t  = 25 °C were investigated. A selection of literature data on ATP protonation constants and on activity isopiestic coefficients was performed, together with new potentiometric measurements (by ISE-H + , glass electrode). Both literature and new experimental data were used to model the dependence on ionic strength and ionic medium of ATP protonation by SIT (Specific ion Interaction Theory) and Pitzer equations. In addition to values of first and second ATP protonation constants in…

Activity coefficientMolar concentrationactivity coefficientsActivity coefficientPotentiometric titrationInorganic chemistryBiophysicsIonic bondingProtonationProtonationATP; protonation; activity coefficients; Dependence on medium and ionic strength; SIT model; Pitzer modelSodium ChlorideBiochemistryPotassium ChlorideAdenosine TriphosphateElectrochemistrySettore CHIM/01 - Chimica AnaliticaChemistryOrganic ChemistryOsmolar ConcentrationPitzer modelSIT modelATPSpecific ion interaction theoryIonic strengthDependence on medium and ionic strengthPhysical chemistryPitzer equationsBiophysical chemistry
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A1 receptor-mediated modulatory effects of adenosine on the contractility in mouse ileum: characterization of signal transduction pathway

2008

AdenosineMouse ileumMechanical activityAdenosine A1 receptorSettore BIO/09 - FisiologiaP1 purinoceptorPotassium channels
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Effect of histamine and histamine analogues on human isolated myometrial strips.

1992

1. The effect of histamine and histamine H1- and H2-receptor agonists on isolated myometrium strips of premenopausal women has been examined. The effect of acetylcholine was also determined. 2. Histamine, 2-pyridylethylamine, 4-methylhistamine and acetylcholine, but not dimaprit, produced a concentration-related contractile response in human isolated myometrial strips. Histamine also produced a further contraction in human isolated myometrial strips precontracted with KCl (55 mM). 3. The contractile response to histamine was antagonized by the histamine H1-receptor antagonist, clemizole (0.1 microM) but was potentiated by the histamine H2-receptor antagonist, ranitidine (10 microM). Clemizo…

AdultAtropinemedicine.medical_specialtyPyridinesMuscle RelaxationHistamine H1 receptorRanitidineHistamine agonistPotassium ChlorideHistamine Agonistschemistry.chemical_compoundHistamine receptorUterine ContractionHistamine H2 receptorInternal medicinemedicineHumansPharmacologyDose-Response Relationship DrugMethylhistaminesMuscle SmoothMiddle AgedDimapritAcetylcholineClemizoleEndocrinologyMuscle relaxationchemistryMyometriumBenzimidazolesFemaleHistamineHistamineResearch ArticleBritish journal of pharmacology
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Chromated metal products may be hazardous to patients with chromate allergy.

2009

Background:  Hidden allergen exposure may contribute to persistence and relapse of chromate dermatitis. According to case reports, chromated metal products, such as screws, fittings, etc., may be relevant allergen sources for patients sensitized to chromate. Objectives:  To examine concomitant patch test reactivity to potassium dichromate 0.5% petrolatum (pet.) and three different types of chromated metal rings. Patients/Methods:  Patients with proven or suspected chromate allergy were patch tested with potassium dichromate 0.5% pet. and three different types of chromated metal rings (yellow, olive, and black). Hexavalent chromium Cr(VI) release from the patch tested rings was chemically an…

AdultChromiumMaleAllergyDermatologyMetal030207 dermatology & venereal diseases03 medical and health scienceschemistry.chemical_compound0302 clinical medicineChromium CompoundsGermanymedicineImmunology and AllergyHumansIn patientHexavalent chromium030223 otorhinolaryngologyPotassium dichromateChromate conversion coatingMetallurgyPatch testAllergensMiddle AgedPatch Testsmedicine.disease3. Good healthchemistryvisual_artDermatitis Allergic Contactvisual_art.visual_art_mediumFemalePotassium DichromateContact dermatitisNuclear chemistryContact dermatitis
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Raltegravir Pharmacokinetics in Patients on Asunaprevir-Daclatasvir.

2015

ABSTRACT Raltegravir pharmacokinetics was studied in 20 patients included in the ANRS HC30 QUADRIH Study before and after addition of anti-hepatitis C virus (anti-HCV) quadritherapy, including pegylated-interferon–ribavirin and asunaprevir plus daclatasvir. Raltegravir pharmacokinetic parameters remained unchanged whether administered on or off anti-HCV therapy. In addition, concentrations of raltegravir, asunaprevir, and daclatasvir were not affected by liver cirrhosis. These data suggest that in human immunodeficiency virus (HIV)-HCV-coinfected patients, whether cirrhotic or not, asunaprevir and daclatasvir could be administered safely with raltegravir.

AdultLiver CirrhosisMaleDaclatasvirPyrrolidinesAlpha interferonHIV InfectionsHepacivirusPharmacologyAntiviral AgentsRaltegravir PotassiumPolyethylene Glycolschemistry.chemical_compoundPharmacokineticsRaltegravir PotassiumRibavirinMedicineHumansPharmacology (medical)PharmacologySulfonamidesbusiness.industryCoinfectionRibavirinImidazolesvirus diseasesInterferon-alphaValineHepatitis CHepatitis C ChronicMiddle AgedRaltegravirmedicine.diseaseIsoquinolinesdigestive system diseasesRecombinant ProteinsInfectious DiseaseschemistryLiverHIV-1AsunaprevirDrug Therapy CombinationFemaleCarbamatesbusinessmedicine.drugAntimicrobial agents and chemotherapy
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Effect of ouabain and furosemide on erythrocyte sodium and phosphate transport.

1981

The effects of ouabain and furosemide on the unidirectional efflux of sodium and phosphate ions were studied in freshly drawn human red blood cells (RBCs). In the presence of physiologic concentrations of sodium and potassium the rate of sodium efflux was reduced by 74% due to ouabain sensitivity. Furosemide (1.0 mmol/l) reduced ouabain-insensitive sodium transport rate by a further 50%. Thus, 13% of total sodium efflux was inhibited by furosemide when ouabain was present. In the absence of ouabain, however, furosemide inhibited 31% of total sodium transport, indicating that it also affected ouabain-sensitive sodium efflux. Phosphate transfer of RBCs was almost 1.0 mmol/l RBCs per hour. Ery…

AdultMaleCell Membrane PermeabilityErythrocytesPotassiumSodiumchemistry.chemical_elementBiological Transport ActiveOuabainIon ChannelsPhosphateschemistry.chemical_compoundHydrolysisFurosemidemedicineHumansPharmacology (medical)OuabainPharmacologyChromatographyChemistrySodiumFurosemidePhosphateBiochemistryPotassiumEffluxSodium-Potassium-Exchanging ATPaseAdenosine triphosphatemedicine.drugClinical pharmacology and therapeutics
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Primordial Prevention of High Blood Pressure in Childhood

2020

Hypertension is a condition with increased risk for subsequent adverse events, and treatment of hypertension is prescribed for primary prevention of adverse events. Primordial prevention is a concept that precedes primary prevention and focuses on risk factor prevention. Primordial prevention of hypertension consists of strategies to maintain blood pressure in a normal range and prevent development of elevated blood pressure or hypertension. Childhood is a period in which primordial prevention could be effective and if sustained throughout childhood could contribute to a healthier young adulthood. Targets for primordial prevention in childhood include preventing and reducing childhood obesi…

AdultMalePediatric ObesityPediatricsmedicine.medical_specialtyAdolescentReproductive Techniques AssistedOffspringChildhood obesityElevated bloodPregnancyRisk FactorsPrevalenceInternal MedicineHumansMedicineSleep HygieneAge of OnsetYoung adultRisk factorChildAdverse effectExerciseLife StyleNormal rangeAir Pollutantsbusiness.industryInfantPotassium DietaryDiet Sodium-RestrictedInfant Low Birth Weightmedicine.diseaseDietPregnancy ComplicationsPrimary PreventionBlood pressureChild PreschoolPrenatal Exposure Delayed EffectsHypertensionFemalebusinessHypertension
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Metabolic Evaluation of 94 Patients 5 to 16 Years After Ileocecal Pouch (Mainz Pouch 1) Continent Urinary Diversion

2003

PURPOSE In continent urinary diversion metabolic disturbances may be encountered in long-term followup. We evaluated metabolic consequences in patients with a minimum followup of 5 years after Mainz pouch 1 urinary diversion.At our institution continent urinary diversion using the ileocecal segment was performed between 1983 and 1995 in 458 patients. A total of 94 patients with an ileocecal pouch for a minimum of 5 years were reevaluated for metabolic changes. Median followup was 9.0 years. Routine laboratory parameters, blood gas analysis, vitamin B12, vitamin D25, cross-laps, bone specific alkaline phosphatase, osteocalcin and propeptide of type I collagen were obtained. Bone density was …

AdultMalePhosphopeptidesmedicine.medical_specialtyBone diseaseBone densityUrologymedicine.medical_treatmentUrinary systemOsteocalcinOsteoporosisSodium CitratePostoperative ComplicationsCalcitriolBone DensityReference ValuesPotassium CitrateHumansMedicineCitratesMegaloblastic anemiaAgedbusiness.industryUrinary Reservoirs ContinentUrinary diversionMiddle AgedAlkaline Phosphatasemedicine.diseaseSurgeryVitamin B 12FemaleCollagenBlood Gas AnalysisPouchAcidosisEnergy MetabolismbusinessContinent Urinary DiversionProcollagenFollow-Up StudiesJournal of Urology
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Vasopressin receptors involved in adrenergic neurotransmission in the circular muscle of the human vas deferens

1998

We studied the effects of vasopressin on the adrenergic responses of in vitro preparations of circular muscle from the vas deferens obtained from 28 men undergoing elective vasectomy. Vasopressin (3 x 10(-9)-3 x 10(-8) M) enhanced the phasic contractions elicited by electrical field stimulation and noradrenaline. This potentiation was blocked by the vasopressin V1 receptor antagonist d(CH2)5Tyr(Me)vasopressin (10(-6) M) but not by the vasopressin V2 receptor antagonist [d(CH2)5, D-Ile2,Ile4,Arg8]vasopressin (10(-6) M). The Ca2+ antagonist nifedipine (10(-6) M) did not affect the potentiation of electrical field stimulation induced by vasopressin and noradrenaline but reduced KCl-induced con…

AdultMaleReceptors Vasopressinmedicine.medical_specialtyVasopressinNifedipineVasopressinsNeuropeptideAdrenergicStimulationIn Vitro TechniquesSynaptic TransmissionPotassium ChlorideNorepinephrineHormone AntagonistsVas DeferensInternal medicinemedicineHumansVasoconstrictor AgentsVasopressin receptorPharmacologyArginine vasopressin receptor 1BChemistryAntagonistVas deferensMuscle SmoothCalcium Channel BlockersElectric StimulationArginine Vasopressinmedicine.anatomical_structureEndocrinologyAdrenergic alpha-AgonistsAntidiuretic Hormone Receptor Antagonistshormones hormone substitutes and hormone antagonistsMuscle ContractionEuropean Journal of Pharmacology
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Endothelium-independent contractions of human cerebral arteries in response to vasopressin.

1990

We studied the effects of vasopressin in isolated segments from branches (500-700 micrograms in external diameter) of human middle cerebral arteries obtained during autopsy of 15 patients who had died 3-8 hours before. Paired segments, one normal and the other de-endothelized by gentle rubbing, were mounted for isometric recording of tension in organ baths. In 11 normal segments, vasopressin produced concentration-dependent contractions with an EC50 of 7.0 X 10(-10) M. Removal of the endothelium from 12 segments did not significantly affect vasopressin-induced contractions. Vasopressin produced further contractions in arterial segments with (n = 4) or without (n = 5) endothelium precontract…

AdultMaleVasopressinmedicine.medical_specialtyEndotheliummedicine.drug_classVasopressinsCerebral arteriesNeuropeptideIn Vitro TechniquesPotassium Chloridemedicine.arteryInternal medicinemedicineHumansAgedAdvanced and Specialized NursingDose-Response Relationship Drugbusiness.industryOsmolar ConcentrationCerebral ArteriesMiddle AgedReceptor antagonistAcetylcholineArginine Vasopressinmedicine.anatomical_structureEndocrinologyVasoconstrictionMiddle cerebral arteryFemaleNeurology (clinical)Endothelium Vascularmedicine.symptomCardiology and Cardiovascular MedicinebusinessAcetylcholineVasoconstrictionmedicine.drugStroke
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