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Background: Primary aldosteronism (PA) is caused by autonomous aldosterone overproduction and characterised by uncontrolled hypertension. There are currently no treatments that target aldosterone synthesis. We evaluated the safety and efficacy of a novel aldosterone synthase inhibitor, dexfadrostat phosphate, in patients with PA. Methods: This multi-centre, randomised, phase 2 trial was conducted between November 2019 and May 2022 (NCT04007406; EudraCT code 2019-000919-85). Adults with PA and an office systolic blood pressure of 145-190 mmHg were included. After a 2-week single-blind placebo run-in period, participants were randomised 1:1:1 to receive oral dexfadrostat phosphate 4, 8, or 12 mg once daily for an 8-week double-blind treatment period, followed by a 2-week single-blind placebo withdrawal period. Randomisation was conducted centrally and stratified by centre and sex. At the beginning and end of the treatment period, 24 h ambulatory systolic blood pressure (aSBP) was recorded. Blood samples were taken every 2 weeks. Primary endpoints were the change in aldosterone-to-renin ratio (ARR) and mean 24 h aSBP from baseline to the end of the treatment period in the combined dose group of all participants receiving any dose of dexfadrostat phosphate. Safety endpoints were the occurrence of treatment-emergent adverse events (TEAEs) and serious adverse events over the entire study in all randomised participants who received at least one dose of dexfadrostat phosphate. Findings: In total, 35 participants received dexfadrostat phosphate and all participants completed the study. Twenty-six participants (74.3%) were male, the mean age was 51.9 years (SD 8.7), and most were White (n = 32, 91.4%). The median ARR and the mean 24 h aSBP significantly decreased from the beginning to the end of the treatment period in the combined dose group (ARR: 15.3 vs 0.6, least-squares mean [LSM] change in log-normal values -2.5, p < 0.0001; aSBP: 142.6 vs 131.9 mmHg, LSM change -10.7 mmHg, p < 0.0001). There were no safety concerns; all TEAEs were mild or moderate and there were no serious TEAEs. Interpretation: Dexfadrostat phosphate corrected the ARR and aSBP and was well tolerated in patients with PA, demonstrating the benefit of pharmacologically targeting the source of hyperaldosteronism. Funding: DAMIAN Pharma AG.
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Aldosterone synthase (CYP11B2) represents a promising drug target because its genetic dysregulation is causally associated with cardiovascular disease, its autonomous activity leads to primary aldosteronism, and its deficiency leads to salt wasting syndromes. The serendipitous discovery that the dextro-rotatory stereoisomer of the racemic aromatase (CYP19A1) inhibitor CGS16949A mediates potent CYP11B2 inhibition led to the purification and clinical development of dexfadrostat phosphate. To characterize the pharmacophore of dexfadrostat phosphate, structure-based enzyme coordination with CYP11B2, CYP11B1 and CYP19A1 was combined with steroid turnover upon in vitro and clinical treatment. Dexfadrostat, but not its 5S-enantiomer (5S-fadrozole), precisely coordinates with the catalytic heme moiety in the space of the CYP11B2 substrate binding pocket forming a tight and stable complex. Conversely, neither rigid nor flexible docking led to a plausible coordination geometry for dexfadrostat in steroid 11ß-hydroxylase (CYP11B1 - orthologue to CYP11B2) or in CYP19A1. The inhibitory preference of dexfadrostat was confirmed in vitro using an adrenal cortex-derived cell line. Dexfadrostat phosphate treatment of healthy subjects in the context of a clinical phase 1 study led to a dose-dependent decrease in urinary aldosterone secretion, accompanied by an increase in urinary corticosterone and deoxycorticosterone metabolites. Increased urinary corticosterone metabolites are indicative of CYP11B2 (18-oxidase) inhibition with clinical features reminiscent of patients with inborn corticosterone methyloxidase type II deficiency. An off-target effect on CYP19A1 was not observed as indicated by no clinical changes in testosterone and estradiol levels. Therefore, dexfadrostat exhibits the ideal structural features for binding and catalytic inhibition of CYP11B2 but not CYP11B1. Clinically, treatment with dexfadrostat phosphate leads to suppression of aldosterone levels by inhibiting predominantly one or both final CYP11B2-mediated reactions.
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Citocromo P-450 CYP11B2 , Esteroide 11-beta-Hidroxilase , Humanos , Esteroide 11-beta-Hidroxilase/genética , Citocromo P-450 CYP11B2/metabolismo , Corticosterona , Aldosterona/metabolismo , Fosfatos , Fadrozol/farmacologiaRESUMO
AIMS: High aldosterone is a key driver of hypertension and long-term negative sequelae. We evaluated the safety and efficacy of dexfadrostat phosphate (DP13), a novel aldosterone synthase (CYP11B2) inhibitor, in healthy participants. METHODS: This randomized, double-blind, placebo-controlled study was conducted in two parts. In part A, a single-ascending dose escalation, 16 participants received oral DP13 1-16 mg. Part B was a multiple-ascending dose, sequential group study in which 32 participants received oral DP13 4, 8 or 16 mg once daily for 8 days. Safety and tolerability were monitored throughout. An adrenocorticotropic hormone (ACTH) stimulation test at maximal blood drug concentrations defined the dose range for multiple dosing. RESULTS: DP13 was well tolerated at all doses, with no serious adverse events. In part B, all DP13 doses (4, 8 and 16 mg) over 8 days effectively suppressed aldosterone production, increased the urinary sodium/potassium ratio, decreased plasma sodium and increased plasma potassium and renin levels compared with placebo, resulting in potent suppression of the aldosterone-to-renin ratio (ARR). Endocrine counter-regulation resulted in the 4 mg dose no longer sustaining 24-h aldosterone suppression after 8 days of treatment, unlike the 8- and 16 mg doses. There was no evidence of drug-induced adrenal insufficiency (ACTH stress challenge). CONCLUSIONS: In patients with excess aldosterone and ensuing sodium retention driving hypertension, managing sodium balance is critical. A CYP11B2 inhibitor like DP13, whose effectiveness can be monitored by a reduction in ARR, may prove valuable in managing aldosterone-dependent hypertension and primary aldosteronism.
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Aldosterona , Hipertensão , Humanos , Aldosterona/uso terapêutico , Renina/uso terapêutico , Citocromo P-450 CYP11B2 , Voluntários Saudáveis , Fosfatos/uso terapêutico , Hipertensão/complicações , Sódio , Hormônio Adrenocorticotrópico , PotássioRESUMO
Prospective payment systems reimburse hospitals based on diagnosis-specific flat fees, which are generally based on average costs. While this encourages cost-consciousness on the part of hospitals, it introduces undesirable incentives for patient transfers. Hospitals might feel encouraged to transfer patients if the expected treatment costs exceed the diagnosis-related flat fee. A transfer fee would discourage such behavior and, therefore, could be welfare enhancing. In 2003, New Zealand introduced a fee to cover situations of patient transfers between hospitals. We investigate the effects of this fee by analyzing 4,020,796 healthcare events from 2000 to 2007 and find a significant reduction in overall transfers after the policy change. Looking at transfer types, we observe a relative reduction in transfers to non-specialist hospitals but a relative increase in transfers to specialist facilities. It suggests that the policy change created a focusing effect that encourages public health care providers to transfer patients only when necessary to specialized providers and retain those patients they can treat. We also find no evidence that the transfer fee harmed the quality of care, measured by mortality, readmission and length of stay. The broader policy recommendation of this research is the introduction or reassessment of transfer payments to improve funding efficiency.
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Sistema de Pagamento Prospectivo , Honorários e Preços , Hospitais , Humanos , Nova Zelândia , PolíticasRESUMO
The technology of 3D-printing has allowed the production of entirely soft pumps with complex chamber geometries. We used this technique to develop a completely soft pneumatically driven total artificial heart from silicone elastomers and evaluated its performance on a hybrid mock circulation. The goal of this study is to present an innovative concept of a soft total artificial heart (sTAH). Using the form of a human heart, we designed a sTAH, which consists of only two ventricles and produced it using a 3D-printing, lost-wax casting technique. The diastolic properties of the sTAH were defined and the performance of the sTAH was evaluated on a hybrid mock circulation under various physiological conditions. The sTAH achieved a blood flow of 2.2 L/min against a systemic vascular resistance of 1.11 mm Hg s/mL (afterload), when operated at 80 bpm. At the same time, the mean pulmonary venous pressure (preload) was fixed at 10 mm Hg. Furthermore, an aortic pulse pressure of 35 mm Hg was measured, with a mean aortic pressure of 48 mm Hg. The sTAH generated physiologically shaped signals of blood flow and pressures by mimicking the movement of a real heart. The preliminary results of this study show a promising potential of the soft pumps in heart replacements. Further work, focused on increasing blood flow and in turn aortic pressure is required.
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Coração Artificial , Hemodinâmica , Impressão Tridimensional , Pressão Arterial , Pressão Sanguínea , Humanos , Teste de Materiais/instrumentação , Modelos Cardiovasculares , Desenho de Prótese , Resistência VascularRESUMO
One of the main concerns about capitation-based reimbursement systems is that tertiary institutions may be underfunded due to insufficient reimbursements of more complicated cases. We test this hypothesis with a data set from New Zealand that, in 2003, introduced a capitation system where public healthcare provider funding is primarily based on the characteristics of the regional population. Investigating the funding for all cases from 2003 to 2011, we find evidence that tertiary providers are at a disadvantage compared with secondary providers. The reasons are that tertiary providers not only attract the most complicated, but also the highest number of cases. Our findings suggest that accurate risk adjustment is crucial to the success of a capitation-based reimbursement system. Copyright © 2017 John Wiley & Sons, Ltd.
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Capitação/estatística & dados numéricos , Pessoal de Saúde/economia , Sistema de Pagamento Prospectivo/economia , Atenção Terciária à Saúde/economia , Adulto , Humanos , Pessoa de Meia-Idade , Nova ZelândiaRESUMO
BACKGROUND: While carbon-encapsulated iron carbide nanoparticles exhibit strong magnetic properties appealing for biomedical applications, potential side effects of such materials remain comparatively poorly understood. Here, we assess the effects of iron-based nanoparticles in an in vivo long-term study in mice with observation windows between 1 week and 1 year. MATERIALS & METHODS: Functionalized (PEG or IgG) carbon-encapsulated platinum-spiked iron carbide nanoparticles were injected intravenously in mice (single or repeated dose administration). RESULTS: One week after administration, magnetic nanoparticles were predominantly localized in organs of the reticuloendothelial system, particularly the lung and liver. After 1 year, particles were still present in these organs, however, without any evident tissue alterations, such as inflammation, fibrosis, necrosis or carcinogenesis. Importantly, reticuloendothelial system organs presented with normal function. CONCLUSION: This long-term exposure study shows high in vivo compatibility of intravenously applied carbon-encapsulated iron nanoparticles suggesting continuing investigations on such materials for biomedical applications.
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Compostos Inorgânicos de Carbono/efeitos adversos , Carbono/efeitos adversos , Materiais Revestidos Biocompatíveis/efeitos adversos , Portadores de Fármacos/efeitos adversos , Compostos de Ferro/efeitos adversos , Nanopartículas/efeitos adversos , Animais , Carbono/administração & dosagem , Carbono/química , Carbono/farmacocinética , Compostos Inorgânicos de Carbono/administração & dosagem , Compostos Inorgânicos de Carbono/química , Compostos Inorgânicos de Carbono/farmacocinética , Materiais Revestidos Biocompatíveis/administração & dosagem , Materiais Revestidos Biocompatíveis/química , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Feminino , Compostos de Ferro/administração & dosagem , Compostos de Ferro/química , Compostos de Ferro/farmacocinética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/ultraestrutura , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/ultraestrutura , Imãs/efeitos adversos , Imãs/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/administração & dosagem , Nanopartículas/análise , Nanopartículas/químicaRESUMO
AIM: Magnetic field guided drug targeting holds promise for more effective cancer treatment. Intravascular application of magnetic nanoparticles, however, bears the risk of potentially important, yet poorly understood side effects, such as off-target accumulation in endothelial cells. MATERIALS & METHODS: Here, we investigated the influence of shear stress (0-3.22 dyn/cm(2)), exposure time (5-30 min) and endothelial activation on the uptake of ferromagnetic carbon-encapsulated iron carbide nanomagnets into endothelial cells in an in vitro flow cell model. RESULTS: We found that even moderate shear stresses typically encountered in the venous system strongly reduce particle uptake compared with static conditions. Interestingly, a pronounced particle uptake was observed in inflamed endothelial cells. CONCLUSION: This study highlights the importance of relevant exposure scenarios accounting for physiological conditions when studying particle-cell interactions as, for example, shear stress and endothelial activation are major determinants of particle uptake. Such considerations are of particular importance with regard to successful translation of in vitro findings into (pre-)clinical end points.
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Sistemas de Liberação de Medicamentos , Células Endoteliais/efeitos dos fármacos , Nanopartículas/química , Carbono/química , Compostos Inorgânicos de Carbono/química , Compostos Inorgânicos de Carbono/farmacologia , Linhagem Celular , Humanos , Compostos de Ferro/química , Compostos de Ferro/farmacologia , Campos Magnéticos , Imãs/química , Nanopartículas/uso terapêutico , Estresse MecânicoRESUMO
Amyloid beta (Aß) protein aggregates, which include fibrils and oligomers, are neurotoxic and are considered to cause Alzheimer's disease. Thus, separation of these Aß aggregates from biological samples is important. Herein, we report the use of strongly ferromagnetic few-layer graphene-coated magnetic nanoparticles (C/Co), which were functionalized with a cationic polymer, poly[3-(methacryloyl amino)propyl]trimethylammonium chloride (polyMAPTAC), C/Co@polyMAPTAC, for the adsorption and magnetic separation of Aß aggregates. Fast adsorption (â¼1 min) of Aß fibrils and oligomers onto the particles was observed. Interestingly, the Aß monomer was not captured by the particles, suggesting that binding to Aß molecules is toxic species-selective. Selective adsorption was also observed in the presence of serum albumin protein. We also showed that C/Co@polyMAPTAC could reduce the cytotoxicity of the Aß aggregate solutions. This study should be useful for further elucidation of the application of nanoparticle adsorption in mediating Aß toxicity.
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A novel solvent-evaporation-based process that exploits template-particle stabilized bicontinuous emulsions for the formation of previously unreached membrane morphologies is reported in this article. Porous membranes have a wide range of applications spanning from water filtration, pharmaceutical purification, and battery separators to scaffolds for tissue engineering. Different situations require different membrane morphologies including various pore sizes and pore gradients. However, most of the previously reported membrane preparation procedures are restricted to specific morphologies and morphology alterations require an extensive optimization process. The tertiary system presented in this article, which consists of a poly(ether sulfone)/dimethylacetamide (PES/DMAc) solution, glycerol, and ZnO-nanoparticles, allows simple and exact tuning of pore diameters ranging from sub-20 nm, up to 100 nm. At the same time, the pore size gradient is controlled from 0 up to 840%/µm yielding extreme asymmetry. In addition to structural analysis, water flux rates of over 5600 L m(-2) h(-1) are measured for membranes retaining 45 nm silica beads.
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Membranas Artificiais , Engenharia Tecidual/métodos , Acetamidas/química , Adsorção , Algoritmos , Cromatografia Líquida , Emulsões , Filtração , Glicerol/química , Espectrometria de Massas , Microscopia Eletrônica de Varredura , Nitrogênio/química , Tamanho da Partícula , Polímeros/química , Porosidade , Solventes/química , Sulfonas/química , Viscosidade , Óxido de Zinco/químicaRESUMO
Multiple studies indicate that endothelin antagonism may have a protective effect for chronic kidney disease. Despite that, clinical studies using avosentan have been halted due to adverse effects including fluid overload. Therefore, we aimed at investigating whether avosentan may have protective effects against hypertensive nephropathy at doses below those inducing fluid-retention. We used double transgenic rats (dTGR), overexpressing both the human renin and angiotensinogen gene, which develop malignant hypertension. Effects of avosentan alone or in combination with low-dose of valsartan (angiotensin AT1 receptor antagonist) on end-organ damage were studied. Avosentan induced a decrease of diuresis (18.3%) with a consequent decrease in hematocrit (8.3%) only at the highest dose investigated (100mg/kg). Treatment with the combination of avosentan and valsartan (10 and 0.1mg/kg, once daily by gavage, respectively) decreased albuminuria to a greater extent than each compound given alone (avosentan: 19.6mg/24h; valsartan: 12.9mg/24h; avosentan+valsartan: 1.7mg/24h, data are median values). Histological severity score also showed a drastic reduction of kidney damage. Furthermore, avosentan alone or in combination therapy dramatically decreased mortality compared to the 100% in untreated animals. These data support a therapeutic effect of avosentan at doses below those inducing fluid overload.
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Hipertensão Renal/tratamento farmacológico , Nefrite/tratamento farmacológico , Piridinas/administração & dosagem , Piridinas/uso terapêutico , Pirimidinas/administração & dosagem , Pirimidinas/uso terapêutico , Albuminúria/tratamento farmacológico , Bloqueadores do Receptor Tipo 1 de Angiotensina II/administração & dosagem , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Angiotensinogênio/biossíntese , Angiotensinogênio/genética , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/uso terapêutico , Diurese/efeitos dos fármacos , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Hematócrito , Humanos , Hipertensão Renal/mortalidade , Hipertensão Renal/patologia , Rim/efeitos dos fármacos , Rim/patologia , Masculino , Nefrite/mortalidade , Nefrite/patologia , Piridinas/efeitos adversos , Pirimidinas/efeitos adversos , Ratos , Ratos Transgênicos , Renina/biossíntese , Renina/genética , Tetrazóis/administração & dosagem , Tetrazóis/uso terapêutico , Valina/administração & dosagem , Valina/análogos & derivados , Valina/uso terapêutico , ValsartanaRESUMO
Intravascular application of magnetic nanocarriers is a critical step in the development of new therapeutic strategies, including magnetic drug targeting or hyperthermia. However, injection of particulate matter bears the intrinsic risk of contact activation of the blood coagulation cascade. In this work, we use point-of-care assays to study coagulation dynamics and clotting parameters in blood samples exposed to relevant concentrations of surface-functionalized carbon-coated iron carbide nanomagnets using unmodified nanomagnets and poly(ethylene)glycol-functionalized nanomagnets with different end-groups, including -OCH3, -NH2, -COOH, -IgG, and -ProteinA-protected-IgG (-IgG-ProtA). Silica nanoparticles with a comparable surface area are used as a reference material. For magnetic nanoparticles, we observe a decrease in clotting time by 25% compared to native blood at concentrations of 1 mg mL-1, independent of the surface functionalization, and only minor differences in receptor expression on platelets (GP-IIb-IIIa, CD62, and CD63) relative to control samples were observed. Interestingly, the inter-subject variance of the clotting time is similar to the nanoparticle-induced effect in a single subject with average clotting time. Whilst the present study is based on in vitro assays and a small group of healthy blood donors, the comparison to broadly used silica nanoparticles, and the fact that experimental intergroup variability is comparable to the observed effects from the carbon-coated nanomagnets suggests continuing investigations on their potential clinical use.
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Nanomaterials are increasingly suggested for the selective adsorption and extraction of complex compounds in biomedicine. Binding of the latter requires specific surface modifications of the nanostructures. However, even complicated macromolecules such as proteins can afford affinities toward basic surface characteristics such as hydrophobicity, topology, and electrostatic charge. In this study, we address these more basic physical interactions. In a model system, the interaction of bovine serum albumin and amyloid ß 42 fibrillar aggregates with carbon-coated cobalt nanoparticles, functionalized with various polymers differing in character, was studied. The possibility of rapid magnetic separation upon binding to the surface represents a valuable tool for studying surface interactions and selectivities. We find that the surface interaction of Aß 42 fibrillar aggregates is mostly hydrophobic in nature. Because bovine serum albumin (BSA) is conformationally adaptive, it is known to bind surfaces with widely differing properties (charge, topology, and hydrophobicity). However, the rate of tight binding (no desorption upon washing) can vary largely depending on the extent of necessary conformational changes for a specific surface. We found that BSA can only bind slowly to polyethylenimine-coated nanomagnets. Under competitive conditions (high excess BSA compared to that for ß 42 fibrillar aggregates), this effect is beneficial for targeting the fibrillar species. These findings highlight the possibility of selective extractions from complex media when advantageous basic physical surface properties are chosen.
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Peptídeos beta-Amiloides/química , Cobalto/química , Nanoestruturas/química , Fragmentos de Peptídeos/química , Soroalbumina Bovina/química , Animais , Ligação Competitiva , Carbono/química , Bovinos , Polietilenoimina/química , Ligação Proteica , Multimerização Proteica , Estrutura Secundária de Proteína , Propriedades de SuperfícieRESUMO
CONTEXT: We describe the clinical investigation of the first generation aldosterone synthase inhibitor, LCI699, in patients with essential, uncontrolled, resistant, or secondary hypertension. LCI699 competitively reduced blood pressure at lower doses yet counterintuitive effects were observed at higher doses. OBJECTIVE AND METHOD: An extensive endocrine biomarker analysis was performed to better understand the pharmacological mechanism of the drug. RESULTS: The interference of LCI699 in the renin-angiotensin-aldosterone system occurred with limited target selectivity, as a dose-dependent compensatory stimulation of the hypothalamic-pituitary-adrenal feedback axis was discovered. Thus, LCI699 affected two endocrine feedback loops that converged at a single point, inhibiting the 11ß-hydroxylase reaction in the adrenal gland, leading to supraphysiological levels of 11-deoxycortiscosterone. The accumulation of this potent mineralocorticoid may explain the blunted blood pressure response to LCI699. CONCLUSION: Future aldosterone synthase inhibitors may improve their target selectivity by sparing the 11ß-hydroxylase reaction and preferentially inhibiting one of the two other enzymatic reactions mediated by aldosterone synthase.
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Anti-Hipertensivos/uso terapêutico , Citocromo P-450 CYP11B2/antagonistas & inibidores , Hiperaldosteronismo/tratamento farmacológico , Hipertensão/tratamento farmacológico , Imidazóis/uso terapêutico , Piridinas/uso terapêutico , Adolescente , Glândulas Suprarrenais/metabolismo , Adulto , Idoso , Aldosterona/sangue , Biomarcadores/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Desoxicorticosterona/metabolismo , Método Duplo-Cego , Hipertensão Essencial , Feminino , Humanos , Hidrocortisona/metabolismo , Hipotálamo/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema Renina-Angiotensina/efeitos dos fármacos , Esteroide 11-beta-Hidroxilase/metabolismo , Resultado do Tratamento , Adulto JovemRESUMO
In a number of clinical conditions such as intoxication, bacteraemia or autoimmune diseases the removal of the disease-causing factor from blood would be the most direct cure. However, physicochemical characteristics of the target compounds limit the applicability of classical filtration and diffusion-based processes. In this work, we present a first in vivo magnetic blood purification rodent animal model and demonstrate its ability to rapidly clear toxins from blood circulation using two model toxins with stable plasma levels (lead (Pb(2+)) and digoxin). Ultra-strong functionalized metal nanomagnets are employed to eliminate the toxin from whole blood in an extracorporeal circuit. In the present experimental demonstration over 40% of the toxin (i.e. lead or digoxin) was removed within the first 10 minutes and over 75% within 40 minutes. After capturing the target substance, a magnetic trap prevents the toxin-loaded nanoparticles from entering the blood circulation. Elemental analysis and magnetic hysteresis measurements confirm full particle recovery by simple magnetic separation (residual particle concentration below 1 µg mL(-1) (detection limit)). We demonstrate that magnetic separation-based blood purification offers rapid blood cleaning from noxious agents, germs or other deleterious materials with relevance to a number of clinical conditions. Based on this new approach, current blood purification technologies can be extended to efficiently remove disease-causing factors, e.g. overdosed drugs, bacteria or cancer cells without being limited by filter cut-offs or column surface saturation.
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Digoxina/isolamento & purificação , Chumbo/isolamento & purificação , Magnetismo , Nanopartículas/metabolismo , Animais , Compostos Inorgânicos de Carbono/química , Digoxina/sangue , Compostos de Ferro/química , Chumbo/sangue , Fígado/patologia , Pulmão/patologia , Masculino , Modelos Animais , Nanopartículas/química , Platina/química , Ratos , Ratos WistarRESUMO
The climate in the stables during the turkeys' first weeks of life is a crucial factor for a successful rearing and the following fattening period. The present study has examined the influence of climate parameters on the foot pad health status of 2681 fattened turkeys from twelve farms during the early rearing phase. In addition to wide-ranging collections of data concerning livestock husbandry and management an examination of the foot pads of 60 animals has been carried out respectively on day 3-5, as well as on day 22-35, shortly before relocation into another stable. For assessing the foot pads a scheme of five categories has been used (ranging from category 0 = no alteration to category 4 = deep lesion). Solely beak trimmed turkeys of the British United Turkeys (BUT) 6 strain, male and female, were examined. In twelve farms air temperature and humidity have been recorded continuously, ammonia and dust concentration were registered on each day of the examination. When assessing the foot pads, the first alterations could already be noted at the age of 3-5 days. On the second period of exzmination 55.6% of the turkeys showed category 2 or category 3. Examinations of the climate parameters showed strong differences concerning temperature, humidity and ammonia concentration among all farms. Using the Fisher's Exact Test, significant dependency of foot pad health on starting temperature (p < 0.001), on temperature measured one week before the second examination (p = 0.004), on humidity (p < 0.001), and on air ammonia concentration (p < 0.001) could be indicated.
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Poluição do Ar em Ambientes Fechados/análise , Criação de Animais Domésticos/normas , Pé/patologia , Abrigo para Animais/normas , Perus , Amônia/análise , Criação de Animais Domésticos/métodos , Animais , Poeira/análise , Feminino , Umidade , Masculino , Temperatura , Perus/classificação , Perus/fisiologiaRESUMO
Aldosterone inhibition with mineralcorticoid receptor antagonists (MRAs) is an effective treatment for resistant hypertension. Aldosterone synthase inhibitors (ASIs) are currently being investigated as a new therapeutic strategy to reduce aldosterone secretion from the adrenal gland. In this study, the efficacy and safety of the first-generation ASI LCI699 (0.25 mg twice daily, 1 mg 4 once daily, and 0.5 mg/1 mg twice daily) was compared with placebo and eplerenone (50 mg twice daily), in patients with resistant hypertension. Placebo-adjusted decreases in systolic blood pressure (BP) with LCI699 ranged from 2.6 mm Hg to 4.3 mm Hg at week 8; changes in diastolic BP ranged from +0.3 mm Hg to -1.2 mm Hg. However, reductions were smaller than observed with eplerenone 50 mg twice daily (9.9 mm Hg and 2.9 mm Hg for systolic and diastolic BP, respectively) and not statistically significant vs placebo. LCI699 suppressed plasma aldosterone levels in a dose-related manner with corresponding dose-dependent increases in plasma renin activity and plasma 11-deoxycorticosterone. LCI699 and eplerenone were well tolerated. These data demonstrate that aldosterone synthesis inhibition with LCI699 lowers BP modestly in patients with resistant hypertension. Aldosterone synthesis inhibition might offer an attractive adjunct to aldosterone receptor blockade, although the potential of a combination MRA/ASI has not yet been tested.
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Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Citocromo P-450 CYP11B2/antagonistas & inibidores , Hipertensão/tratamento farmacológico , Imidazóis/uso terapêutico , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Piridinas/uso terapêutico , Espironolactona/análogos & derivados , Adolescente , Adulto , Idoso , Anti-Hipertensivos/efeitos adversos , Método Duplo-Cego , Eplerenona , Feminino , Humanos , Islândia , Imidazóis/administração & dosagem , Imidazóis/efeitos adversos , Masculino , Pessoa de Meia-Idade , Antagonistas de Receptores de Mineralocorticoides/administração & dosagem , Antagonistas de Receptores de Mineralocorticoides/efeitos adversos , Estudos Prospectivos , Piridinas/administração & dosagem , Piridinas/efeitos adversos , Espironolactona/administração & dosagem , Espironolactona/efeitos adversos , Espironolactona/uso terapêutico , Resultado do Tratamento , Estados Unidos , Adulto JovemRESUMO
OBJECTIVES: The aim of this study was to assess the effects of serelaxin on short-term changes in markers of organ damage and congestion and relate them to 180-day mortality in patients with acute heart failure. BACKGROUND: Hospitalization for acute heart failure is associated with high post-discharge mortality, and this may be related to organ damage. METHODS: The Pre-RELAX-AHF (Relaxin in Acute Heart Failure) phase II study and RELAX-AHF phase III study were international, multicenter, double-blind, placebo-controlled trials in which patients hospitalized for acute heart failure were randomized within 16 h to intravenous placebo or serelaxin. Each patient was followed daily to day 5 or discharge and at days 5, 14, and 60 after enrollment. Vital status was assessed through 180 days. In RELAX-AHF, laboratory evaluations were performed daily to day 5 and at day 14. Plasma levels of biomarkers were measured at baseline and days 2, 5, and 14. All-cause mortality was assessed as a safety endpoint in both studies. RESULTS: Serelaxin reduced 180-day mortality, with similar effects in the phase II and phase III studies (combined studies: N = 1,395; hazard ratio: 0.62; 95% confidence interval: 0.43 to 0.88; p = 0.0076). In RELAX-AHF, changes in markers of cardiac (high-sensitivity cardiac troponin T), renal (creatinine and cystatin-C), and hepatic (aspartate transaminase and alanine transaminase) damage and of decongestion (N-terminal pro-brain natriuretic peptide) at day 2 and worsening heart failure during admission were associated with 180-day mortality. Serelaxin administration improved these markers, consistent with the prevention of organ damage and faster decongestion. CONCLUSIONS: Early administration of serelaxin was associated with a reduction of 180-day mortality, and this occurred with fewer signs of organ damage and more rapid relief of congestion during the first days after admission.
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Biomarcadores/sangue , Insuficiência Cardíaca/tratamento farmacológico , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Relaxina/farmacologia , Doença Aguda , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Creatinina/sangue , Cistatina C/sangue , Método Duplo-Cego , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/mortalidade , Hospitalização , Humanos , Rim/metabolismo , Fígado/metabolismo , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Relaxina/administração & dosagem , Taxa de Sobrevida , Resultado do Tratamento , Troponina T/sangueRESUMO
BACKGROUND: Serelaxin, recombinant human relaxin-2, is a vasoactive peptide hormone with many biological and haemodynamic effects. In a pilot study, serelaxin was safe and well tolerated with positive clinical outcome signals in patients with acute heart failure. The RELAX-AHF trial tested the hypothesis that serelaxin-treated patients would have greater dyspnoea relief compared with patients treated with standard care and placebo. METHODS: RELAX-AHF was an international, double-blind, placebo-controlled trial, enrolling patients admitted to hospital for acute heart failure who were randomly assigned (1:1) via a central randomisation scheme blocked by study centre to standard care plus 48-h intravenous infusions of placebo or serelaxin (30 µg/kg per day) within 16 h from presentation. All patients had dyspnoea, congestion on chest radiograph, increased brain natriuretic peptide (BNP) or N-terminal prohormone of BNP, mild-to-moderate renal insufficiency, and systolic blood pressure greater than 125 mm Hg. Patients, personnel administering study drug, and those undertaking study-related assessments were masked to treatment assignment. The primary endpoints evaluating dyspnoea improvement were change from baseline in the visual analogue scale area under the curve (VAS AUC) to day 5 and the proportion of patients with moderate or marked dyspnoea improvement measured by Likert scale during the first 24 h, both analysed by intention to treat. This trial is registered at ClinicalTrials.gov, NCT00520806. FINDINGS: 1161 patients were randomly assigned to serelaxin (n=581) or placebo (n=580). Serelaxin improved the VAS AUC primary dyspnoea endpoint (448 mmâ×âh, 95% CI 120-775; p=0·007) compared with placebo, but had no significant effect on the other primary endpoint (Likert scale; placebo, 150 patients [26%]; serelaxin, 156 [27%]; p=0·70). No significant effects were recorded for the secondary endpoints of cardiovascular death or readmission to hospital for heart failure or renal failure (placebo, 75 events [60-day Kaplan-Meier estimate, 13·0%]; serelaxin, 76 events [13·2%]; hazard ratio [HR] 1·02 [0·74-1·41], p=0·89] or days alive out of the hospital up to day 60 (placebo, 47·7 [SD 12·1] days; serelaxin, 48·3 [11·6]; p=0·37). Serelaxin treatment was associated with significant reductions of other prespecified additional endpoints, including fewer deaths at day 180 (placebo, 65 deaths; serelaxin, 42; HR 0·63, 95% CI 0·42-0·93; p=0·019). INTERPRETATION: Treatment of acute heart failure with serelaxin was associated with dyspnoea relief and improvement in other clinical outcomes, but had no effect on readmission to hospital. Serelaxin treatment was well tolerated and safe, supported by the reduced 180-day mortality. FUNDING: Corthera, a Novartis affiliate company.
Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Relaxina/uso terapêutico , Doença Aguda , Idoso , Método Duplo-Cego , Dispneia/tratamento farmacológico , Dispneia/etiologia , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Humanos , Tempo de Internação , Masculino , Proteínas Recombinantes/uso terapêutico , Taxa de SobrevidaRESUMO
This work describes a magnetic separation-based approach using polymyxin B-functionalized metal alloy nanomagnets for the rapid elimination of endotoxins from human blood in vitro and functional assays to evaluate the biological relevance of the blood purification process. Playing a central role in gram-negative sepsis, bacteria-derived endotoxins are attractive therapeutic targets. However, both direct endotoxin detection in and removal from protein-rich fluids remains challenging. We present the synthesis and functionalization of ultra-magnetic cobalt/iron alloy nanoparticles and a magnetic separation-based approach using polymyxin B-functionalized nanomagnets to remove endotoxin from human blood in vitro. Conventional chromogenic Limulus Amebocyte Lysate assays confirm decreased endotoxin activity in purified compared to untreated samples. Functional assays assessing key steps in host defense against bacteria show an attenuated inflammatory mediator expression from human primary endothelial cells in response to purified blood samples compared to untreated blood and less chemotactic activity. Exposing Escherichia coli-positive blood samples to polymyxin B-functionalized nanomagnets even impairs the ability of gram-negative bacteria to form colony forming units, thus making magnetic separation based blood purification a promising new approach for future sepsis treatment.