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1.
Eur J Heart Fail ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783712

RESUMO

AIMS: Many patients with heart failure (HF) have chronic kidney disease (CKD) and may not tolerate mineralocorticoid receptor antagonists. We investigated the efficacy and safety of the novel mineralocorticoid receptor modulator balcinrenone in combination with dapagliflozin in a phase 2b study. METHODS AND RESULTS: From January 2021 to October 2023, we randomized 133 adults with symptomatic HF, ejection fraction <60%, estimated glomerular filtration rate (eGFR) ≥30 to ≤60 ml/min/1.73 m2 and urinary albumin-to-creatinine ratio (UACR) ≥30 to <3000 mg/g, to receive balcinrenone 15, 50 or 150 mg/day plus dapagliflozin 10 mg/day, or dapagliflozin 10 mg/day plus placebo, for 12 weeks. Enrolment was stopped early because of slow recruitment. Relative reductions in UACR from baseline to week 12 (primary endpoint) were not significantly different between the balcinrenone plus dapagliflozin groups versus dapagliflozin plus placebo. There was no clear balcinrenone dose-response relationship. There were possible dose-dependent increases in serum potassium levels, reduced eGFR in the highest dose group, and non-significant trends towards reduced N-terminal pro-B-type natriuretic peptide levels. Hyperkalaemia adverse events led to discontinuation in two participants receiving balcinrenone plus dapagliflozin and none in those receiving dapagliflozin plus placebo. CONCLUSION: While the smaller than planned sample size limits interpretation, we did not see significant reduction in UACR in patients treated with balcinrenone plus dapagliflozin compared with dapagliflozin plus placebo.

2.
Drug Metab Dispos ; 51(8): 995-1004, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37407094

RESUMO

An absorption, distribution, metabolism, and excretion study was performed to determine the basic pharmacokinetic parameters, mass balance, and metabolite profiles of balcinrenone, a mineralocorticoid receptor modulator, in humans. This open-label, single-center, nonrandomized study had a two-period design. In period 1, eight healthy male subjects were dosed with a microtracer intravenous infusion of [14C]balcinrenone shortly after receiving an oral dose of unlabeled balcinrenone in a capsule. Following a 7-day washout, the same group of subjects subsequently received an oral dose of [14C]balcinrenone as a suspension in period 2. Clearance and absolute bioavailability of balcinrenone were determined to be 14.2 l/h and 52%, respectively. Renal clearance was determined to be 5.4 l/h (>fu • glomerular filtration rate), indicating elimination via active tubular secretion, which was potentially mediated by P-glycoprotein 1 and/or organic anion transporter 3, according to in vitro transporter data. In total, 94.1% of the oral dose was recovered: 45.2% in the urine and 48.9% in the feces. Balcinrenone was primarily metabolized via oxidation, and in vitro data suggest that cytochrome P450 3A4 was the main enzyme responsible. Intact [14C]balcinrenone accounted for 55% of drug-related material in the plasma; four metabolites were identified, each representing <6% of the total plasma radioactivity. In conclusion, this two-period study has determined the basic pharmacokinetic parameters of balcinrenone in humans, including absolute bioavailability and disposition. No metabolites warranted further evaluation on account of their low representation, and any contribution to the pharmacodynamic response or potential drug-drug interactions was deemed negligible. SIGNIFICANCE STATEMENT: This study provides a detailed understanding of the pharmacokinetics, disposition, and metabolism of balcinrenone following oral and microtracer intravenous administration in humans. In vitro phenotyping and transporter data granted mechanistic insights into the absorption, distribution, metabolism, and excretion properties of balcinrenone. This knowledge will guide future nonclinical and clinical studies evaluating drug-drug interactions, organ dysfunction, and safety of metabolites.


Assuntos
Líquidos Corporais , Humanos , Masculino , Voluntários Saudáveis , Administração Intravenosa , Disponibilidade Biológica , Administração Oral
3.
Transfusion ; 58(9): 2129-2138, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30204953

RESUMO

BACKGROUND: The short dating period of room temperature-stored platelets (PLTs; 5-7 days) limits their availability at far-forward combat facilities and at remote civilian sites in the United States. PLT cryopreservation in 6% DMSO and storage for up to 2 years may improve timely availability for bleeding patients. STUDY DESIGN AND METHODS: A dose escalation trial of DMSO-cryopreserved PLTs (CPPs) compared to standard liquid-stored PLTs (LSPs) was performed in bleeding patients with thrombocytopenia. Within each of four cohorts, six patients received escalating doses of CPP (0.5 unit, 1 unit, and sequential transfusions of 2 and 3 units) and one received a LSP transfusion. Patients were monitored for adverse events (AEs), coagulation markers, PLT responses, and hemostatic efficacy. RESULTS: Patients with a World Health Organization bleeding score of 2 or more received from 0.5 to 3 units of CPP (n = 24) or 1 unit of LSP (n = 4). There were no related thrombotic or other serious AEs experienced. Mild transfusion-related AEs of chills and fever (n = 1), transient increased respiratory rate (n = 1), DMSO-related skin odor (n = 2), and headache (n = 1) were observed after CPP transfusion. Among CPP recipients 14 of 24 (58%) had improved bleeding scores, including three of seven (43%) patients who had intracerebral bleeding. CPP posttransfusion PLT increments were significantly less than those of LSPs; however, days to next transfusion were the same. After transfusion, the CPP recipients had improvements in some variables of thrombin generation tests and thromboelastography. CONCLUSION: Cryopreserved PLT transfusions appear to be safe and effective when given to bleeding patients with thrombocytopenia.


Assuntos
Preservação de Sangue/métodos , Criopreservação/métodos , Hemorragia/terapia , Transfusão de Plaquetas , Trombocitopenia/terapia , Adulto , Idoso , Micropartículas Derivadas de Células , Crioprotetores/efeitos adversos , Dimetil Sulfóxido/efeitos adversos , Feminino , Neoplasias Hematológicas/terapia , Hemorragia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Transfusão de Plaquetas/efeitos adversos , Índice de Gravidade de Doença , Trombocitopenia/complicações , Adulto Jovem
4.
J Spec Oper Med ; 17(2): 49-58, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28599034

RESUMO

This study focused on a clinically relevant healthcare problem in the military: acute soft tissue wounds, or blisters. The trial was a prospective, controlled, randomized two-arm study evaluating the efficacy of a bioelectric dressing, Procellera®, applied topically two to three times per week for 2 weeks to blisters developed in Ranger trainees during training at Fort Benning, Georgia. A total of 80 US Army Ranger recruits with blister wounds below the knee were randomly assigned to one of two treatment groups (n = 40/group). The primary goal was to assess the clinical efficacy (rate of healing) of administered Procellera in conjunction with the standard-of-care (SOC) treatment, moleskin and Tegaderm ®, on the healing rate of blisters compared with the SOC treatment alone. The secondary end points for efficacy were the quantities of wound fluid biomarkers and bacterial bioburden. The tertiary end point was assessment of pain in the treatment group compared with that of the control group during the 2-week study. The results showed no statistical difference between the SOC and SOC+Procellera groups in wound healing and pain. Wound fluid was reported for 24 participants (64.9%) in the SOC group and 21 participants (56.8%) in SOC+Procellera group at the baseline measurement (ρ = .475); however, the wounds were devoid of fluid on follow-up visits. The mild nature of the wounds in this study was apparent by the low pain scores at the beginning of the study, which disappeared by the follow-up visits. The average wound sizes were 2.2cm2 and 1.5cm2 for the SOC and SOC+Procellera groups, respectively. This trial protocol should be conducted on open softtissue wounds in severe heat. To our knowledge, this is the first clinical study conducted within the US Army Rangers training doctrine.


Assuntos
Bandagens , Vesícula/terapia , Terapia por Estimulação Elétrica , Traumatismos da Perna/terapia , Medicina Militar , Militares , Cicatrização , Bactérias/genética , Fontes de Energia Bioelétrica , Vesícula/imunologia , Vesícula/microbiologia , Citocinas/imunologia , Humanos , Traumatismos da Perna/imunologia , Traumatismos da Perna/microbiologia , Dor , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo
5.
Injury ; 47(10): 2097-2104, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27423308

RESUMO

OBJECTIVES: Perforation of the chest (open pneumothorax) with and without lung injury can cause air accumulation in the chest, positive intrapleural pressure and lead to tension pneumothorax if untreated. The performance of chest seals to prevent tension physiology depends partially on their ability to adhere to the skin and seal the chest wound. Novel non-occlusive vented chest seals were assessed for their adhesiveness on skin of live swine under normal and extreme environmental conditions to simulate austere battlefield conditions. METHODS: Chest seals were applied on the back of the swine on skin that was soiled by various environmental contaminants to represent battlefield situations. A peeling (horizontal rim peeling) and detachment and breaching (vertical pulling) techniques were used to quantify the adhesive performance of vented chest seals. Among eight initially selected vented seals, five (Bolin, Russell, Fast breathe, Hyfin and SAM) were further down-selected based on their superior adherence scores at ambient temperatures. The adherence of these seals was then assessed after approximately 17h storage at extreme cold (-19.5°C) and hot (71.5°C) temperatures. RESULTS: Adherence scores for peeling (above 90%) and detachment scores (less than 25%) were comparable for four vented chest seals when tested at ambient temperature, except for the Bolin seal which had higher breaching. Under extreme storage temperatures, adherence peeling scores were comparable to those at ambient temperatures for four chest seals. Scores were significantly lower for the Bolin seal at extreme temperatures. This seal also had the highest detachment and breaching scores. In contrast, the Russell, Fast breathe, Hyfin and SAM seals showed similar ability to stay air tight without breaching after hot storage. CONCLUSION: No significant difference was found in skin adherence of the five vented chest seals at ambient temperature and the four seals (Russell, Fast breathe, Hyfin and SAM) maintained superior adherence even after exposure to extreme temperatures compared to the Bolin. To select the most effective product from the 5 selected vented chest seals, further functional evaluation of the valve of these chest seals on a chest wound with the potential for tension in the pneumothorax or hemopneumothorax is warranted.


Assuntos
Curativos Oclusivos/estatística & dados numéricos , Pneumotórax/prevenção & controle , Traumatismos Torácicos/patologia , Adesivos Teciduais/farmacologia , Ferimentos Penetrantes/patologia , Animais , Modelos Animais de Doenças , Tratamento de Emergência , Desenho de Equipamento , Teste de Materiais , Medicina Militar , Suínos
6.
Mil Med ; 181(5 Suppl): 184-90, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27168571

RESUMO

Novel approaches including nonpharmacological methodologies for prevention and control of microbial pathogens and emerging antibiotic resistance are urgently needed. Procellera is a wound care device consisting of a matrix of alternating silver (Ag) and zinc (Zn) dots held in position on a polyester substrate with a biocompatible binder. This electroceutical medical device is capable of generating a direct current voltage (0.5-0.9 Volts). Wound dressings containing metals such as Ag and/or Zn as active ingredients are being used for control of colonized and infected wounds. Reports on the presence of electric potential field across epithelium and wound current on wounding have shown that wound healing is enhanced in the presence of an external electrical field. However, majority of the electrical devices require an external power source for delivering pulsed or continuous electric power at the wound site. A microelectric potential-generating system without an external power source is an ideal treatment modality for application in both clinical and field settings. The research presented herein describes efficacy evaluation of a wireless bioelectric dressing against both planktonic and biofilm forms of wound pathogens including multidrug resistant organisms.


Assuntos
Bandagens/normas , Eletroquimioterapia/métodos , Eletroquimioterapia/normas , Cicatrização , Infecção dos Ferimentos/prevenção & controle , Biofilmes , Humanos , Poliésteres/administração & dosagem , Poliésteres/uso terapêutico , Prata/uso terapêutico , Zinco/uso terapêutico
7.
J Spec Oper Med ; 16(1): 29-35, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27045491

RESUMO

BACKGROUND: Emergency tourniquet use has been associated with hemorrhage control and improved survival during the wars since 2001. The purpose of the present study is to compare the differential performance of two new tactical tourniquets with the standard-issue tourniquet to provide preliminary evidence to guide decisions on device development. METHODS: A laboratory experiment was designed to test the effectiveness of tourniquets on a manikin thigh. Three models of tourniquets were assessed. The Rapid Application Tourniquet System (RATS) and the Tactical Mechanical Tourniquet (TMT) were compared with the standard-issue Combat Application Tourniquet(®) (C-A-T). Two users conducted 30 tests each. RESULTS: Percentages for effectiveness (hemorrhage control, yes/no) and distal pulse cessation did not differ significantly by model. When compared with the RATS, the C-A-T performed better (ρ < .001) for time to hemorrhage control and fluid loss. The C-A-T and TMT had comparable responses for most measures, but the C-A-T applied more pressure (ρ = .04) than did the TMT for hemorrhage control. CONCLUSION: All three tactical tourniquets showed substantial capacity for hemorrhage control. However, the two new tourniquet models (RATS and TMT) did not offer any improvement over the C-A-T, which is currently issued to military services. Indeed, one of the new models, the RATS, was inferior to the C-A-T in terms of speed of application and simulated loss of blood. Opportunities were detected for refinements in design of the two new tourniquets that may offer future improvements in their performance.


Assuntos
Primeiros Socorros/instrumentação , Hemorragia/terapia , Torniquetes , Volume Sanguíneo , Desenho de Equipamento , Equipamentos e Provisões , Humanos , Manequins , Coxa da Perna , Fatores de Tempo
8.
Open Microbiol J ; 8: 15-21, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24627730

RESUMO

Silver-based wound dressings have been developed for the control of bioburden in wounds. However, the popularity and extensive use of silver-based dressings has been associated with emerging microbial resistances to silver. In this study we examined in vitro antibacterial efficacy of a bioelectric dressing containing silver and zinc against various wound pathogens. Antibiotic-sensitive clinical wound isolates showed a 100% reduction in bacterial growth, except that Enterococcus faecalis isolate was shown to survive with a bacterial log10 reduction rate of less than 10(2) CFU. We also investigated antibacterial efficacy against the extended spectrum ß-lactamase (ESBL) bacteria, multidrug-resistant (MDR) bacteria, and methicillin-resistant Staphylococcus aureus (MRSA). The bioelectric dressing was effective in killing wound pathogens including ESBL, MDR, and MRSA in vitro. Furthermore, based on the primary results against E. faecalis, we carried out extensive studies against several nosocomial Enterococcus species including vancomycin-resistant species. Overall, the vancomycin-sensitive or -resistant Enterococcus species were resistant to this dressing at up to 48 h, except for the vancomycin-resistant Enterococcus raffinosus isolate only showing a 100% bacterial reduction at 48 h, but not at 24 h. The results demonstrated the effective bactericidal activity of a bioelectric dressing against antibiotic-sensitive and MDR strains, but Enterococcus species are bacteriostatic.

9.
Anadolu Kardiyol Derg ; 12(5): 420-6, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22591937

RESUMO

OBJECTIVE: Functionally univentricular heart (FUH) anomalies are the leading cause of death from all structural birth defects. Total cavopulmonary connection (TCPC) is the last stage of the palliative surgical reconstruction with significant late hemodynamic complications requiring high-risk heart transplantation. Alternative therapeutic options for these critically ill patients are crucial. In Phase I, we investigated the effect of pulsatility of venous flow (VF) waveform on the performance of functional and "failing" Fontan (FF) patients based on conduit power loss. In phase 2, the effect of enhanced external counter pulsation on Fontan circulation flow rates is monitored. METHODS: In phase 1, Doppler VFs were acquired from FF patients with ventricle dysfunction. Using computational fluid dynamics (CFD), hemodynamic efficiencies of the FF, functional and in-vitro generated mechanically assisted VF waveforms were evaluated. In phase 2, Fontan circulation on sheep model was created and enhanced external counter pulsation (EECP) applied. RESULTS: Variations in the pulsatile content of the VF waveforms altered conduit efficiency notably. High frequency and low amplitude oscillations lowered the pulsatile component of power losses in FF VF waveforms. The systemic venous flow, pulmonary artery and aorta flows increased by utilizing EECP. CONCLUSION: Our data highlighted the significance of VF pulsatility on energy efficiency inside SV circulation and the feasibility of VF waveform optimization. EECP assist in Fontan circulation can result in venous flow augmentation.


Assuntos
Técnica de Fontan , Cardiopatias Congênitas/cirurgia , Ventrículos do Coração/anormalidades , Pressão Ventricular/fisiologia , Adolescente , Adulto , Animais , Modelos Animais de Doenças , Feminino , Cardiopatias Congênitas/fisiopatologia , Ventrículos do Coração/fisiopatologia , Coração Auxiliar , Hemodinâmica , Humanos , Masculino , Fluxo Pulsátil/fisiologia , Ovinos
10.
Resuscitation ; 83(4): 505-10, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21963815

RESUMO

BACKGROUND: There are few if any real-time physiologic measures that currently provide feedback during resuscitation from cardiac arrest. Such measures could be used to guide therapy not simply based on process guidelines but on the physiologic response of the patient from moment to moment. To this end, we applied an existing technology - quantitative waveform measures (QWMs) of the ventricular fibrillation (VF) electrocardiogram (ECG) - as a continuous measure of myocardial response to reperfusion with cardiopulmonary bypass (CPB) after prolonged cardiac arrest. METHODS: Sixteen domestic, mixed-breed swine were sedated, anesthetized and paralyzed. Mechanical ventilation with room air was provided. Large diameter bypass catheters were placed in the right external jugular vein and right femoral artery for cardiopulmonary bypass (CPB). VF was induced with a 3-s 100mA transthoracic shock and left untreated for 15, 20, 25, or 30min, followed by 10min of centrifugal pump CPB (Bard CPS). Continuous Lead II ECG was recorded with an electronic data acquisition system (Power Lab, ADInstruments). Four QWMs representing 4 signal characteristics of the VF ECG were calculated in 5-s windows throughout the course of untreated VF and resuscitation with CPB. RESULTS: Four animals were assigned to each VF duration group. QWM recovery was inversely correlated with untreated VF duration, and was drastically reduced above 20min of untreated VF. Return of spontaneous circulation (ROSC) was highly unlikely after 20min of untreated VF. CONCLUSION: QWMs of the VF ECG provided a real-time metric of myocardial electrophysiologic response to reperfusion with CPB. Resuscitation from greater than 20min of untreated cardiac arrest was unlikely. QWMs may be useful for titrating CPB duration before defibrillation and assessing CPR quality independently of process guidelines.


Assuntos
Reanimação Cardiopulmonar/métodos , Eletrocardiografia/métodos , Parada Cardíaca/terapia , Fibrilação Ventricular/diagnóstico , Animais , Ponte Cardiopulmonar , Modelos Animais de Doenças , Retroalimentação Fisiológica , Feminino , Monitorização Fisiológica/instrumentação , Distribuição Aleatória , Sensibilidade e Especificidade , Sus scrofa , Suínos , Fibrilação Ventricular/terapia , Remodelação Ventricular/fisiologia
11.
Tissue Eng Part C Methods ; 18(2): 133-42, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21933020

RESUMO

Continuous production of red blood cells (RBCs) in an automated closed culture system using hematopoietic stem cell (HSC) progenitor cell populations is of interest for clinical application because of the high demand for blood transfusions. Previously, we introduced a four-compartment bioreactor that consisted of two bundles of hollow fiber microfiltration membranes for transport of culture medium (forming two medium compartments), interwoven with one bundle of hollow fiber membranes for transport of oxygen (O(2)), carbon dioxide (CO(2)), and other gases (forming one gas compartment). Small-scale prototypes were developed of the three-dimensional (3D) perfusion cell culture systems, which enable convection-based mass transfer and integral oxygenation in the cell compartment. CD34(+) HSC were isolated from human cord blood units using a magnetic separation procedure. Cells were inoculated into 2- or 8-mL scaled-down versions of the previously designed 800-mL cell compartment devices and perfused with erythrocyte proliferation and differentiation medium. First, using the small-scale 2-mL analytical scale bioreactor, with an initial seeding density of 800,000 cells/mL, we demonstrated approximately 100-fold cell expansion and differentiation after 7 days of culture. An 8-mL laboratory-scale bioreactor was then used to show pseudocontinuous production by intermediately harvesting cells. Subsequently, we were able to use a model to demonstrate semicontinuous production with up to 14,288-fold expansion using seeding densities of 800,000 cells/mL. The down-scaled culture technology allows for expansion of CD34(+) cells and stimulating these progenitors towards RBC lineage, expressing approximately 40% CD235(+) and enucleation. The 3D perfusion technology provides an innovative tool for studies on RBC production, which is scalable.


Assuntos
Reatores Biológicos , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Linhagem da Célula , Eritrócitos/citologia , Células-Tronco Hematopoéticas/citologia , Membranas Artificiais , Resinas Acrílicas/química , Antígenos de Superfície/metabolismo , Contagem de Células , Diferenciação Celular , Sobrevivência Celular , Células Cultivadas , Eritrócitos/ultraestrutura , Citometria de Fluxo , Imunofluorescência , Glucose/metabolismo , Células-Tronco Hematopoéticas/ultraestrutura , Humanos , Ácido Láctico/biossíntese , Perfusão , Coloração e Rotulagem , Fatores de Tempo
12.
Resuscitation ; 83(1): 130-3, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21835144

RESUMO

BACKGROUND: Recently, portable extracorporeal membrane oxygenation (ECMO) machines have become commercially available. This creates the potential to utilize extracorporeal life support (ECLS) for the treatment of sudden cardiac arrest in the emergency department, and potentially in the out-of-hospital setting. OBJECTIVE: We sought to determine the feasibility of installing the ECMO circuit during delivery of mechanical chest compression CPR. METHODS: We used 5 mixed-breed domestic swine with a mean mass of 26.0 kg. After induction of anesthesia, animals were instrumented with micromanometer-tipped transducers placed in the aorta and right atrium via the left femoral artery and vein. Ventricular fibrillation (VF) was induced electrically with a transthoracic shock and left untreated for 8 min. Then, mechanical chest compressions were begun (LUCAS, Jolife, Lund, Sweden) and manual ventilations were performed to maintain ETCO(2) between 35 and 45Torr. Compressions continued until ECMO flow was started. Ten minutes after induction of VF, drugs were given (epinephrine, vasopressin, and propranolol). ECMO installation was started via cutdown on the right external jugular vein and right femoral artery for placement of venous and arterial catheters while chest compressions continued. ECMO installation start time varied from 17 to 30 min after start of compressions and continued until ECG indicated a shockable rhythm. First rescue shocks were given at 22, 32, 35, 44, and 65 min. RESULTS: ECMO was successfully installed in all five animals without incident. It was necessary to briefly discontinue chest compressions during the most delicate part of inserting the catheters into the vessels. ECMO also allowed for very rapid cooling of the animals and facilitated post-resuscitation hemodynamic support. Only the 65-min animal did not attain return of spontaneous circulation (ROSC). CONCLUSION: Mechanical chest compression may be a suitable therapeutic bridge to the installation of ECMO and does not interfere with ECMO catheter placement.


Assuntos
Reanimação Cardiopulmonar/métodos , Circulação Extracorpórea/métodos , Parada Cardíaca/terapia , Massagem Cardíaca/métodos , Animais , Modelos Animais de Doenças , Estudos de Viabilidade , Feminino , Parada Cardíaca/fisiopatologia , Hemodinâmica/fisiologia , Projetos Piloto , Respiração Artificial/métodos , Suínos , Tórax/fisiopatologia , Resultado do Tratamento
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