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1.
J Pers Med ; 14(4)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38673062

RESUMO

Orthostatic intolerance is a broad term that represents a spectrum of dysautonomic disorders, including postural orthostatic tachycardia syndrome (POTS) and orthostatic hypotension (OH), as manifestations of severe autonomic failure. While the etiology of orthostatic intolerance has not yet fully been uncovered, it has been associated with multiple underlying pathological processes, including peripheral neuropathy, altered renin-aldosterone levels, hypovolemia, and autoimmune processes. Studies have implicated adrenergic, cholinergic, and angiotensin II type I autoantibodies in the pathogenesis of orthostatic intolerance. Several case series have demonstrated that immunomodulation therapy resulted in favorable outcomes, improving autonomic symptoms in POTS and OH. In this review, we highlight the contemporary literature detailing the association of autoimmunity with POTS and OH.

2.
Hosp Pract (1995) ; : 1-7, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563807

RESUMO

INTRODUCTION: Heart failure is a pressing public health concern, affecting millions in the United States and projected to rise significantly by 2030. Iron deficiency, prevalent in nearly half of ambulatory heart failure patients, contributes to anemia and diminishes patient outcomes. In this study, we aim to evaluate the impact of iron deficiency anemia on acute heart failure hospitalizations outcomes. METHODS: Utilizing the 2019 National Inpatient Sample (NIS) database, a retrospective observational study assessed 112,864 adult patients hospitalized with heart failure and 7,865 cases also had a concomitant diagnosis of iron deficiency anemia (IDA). RESULTS: Among 112,864 heart failure hospitalizations in 2019, approximately 7% had concomitant iron deficiency anemia (IDA). Heart failure patients with IDA exhibited distinct demographic characteristics, with females comprising 51.1% (p < 0.01) and higher rates of complicated hypertension (p < 0.01), complicated diabetes (p < 0.01), and peripheral vascular disease (p < 0.01). Adjusted mean LOS for patients with IDA was significantly longer at 1.31 days (95% CI 0.71-1.47; p < 0.01), persisting in both HFpEF and HFrEF subgroups. While total hospital charges were comparable in HFpEF, HFrEF patients with IDA incurred significantly higher charges ($13427.32, 95% CI: 1463.35-$25391.29, p = 0.03) than those without IDA. Complications such as atrial fibrillation and acute kidney injury were notably more prevalent in HFpEF and HFrEF patients with IDA. CONCLUSION: The study highlighted that iron deficiency in heart failure patients leads to extended hospital stays, increased costs, and heightened risks of specific complications, particularly in HFrEF. Our study emphasized the implications of IDA in patients with heart failure ranging from prolonged hospitalizations and increased costs. Addressing iron deficiency is crucial, given its substantial impact on heart failure hospitalizations and outcomes, emphasizing the need for proactive diagnosis and management.

5.
J Appl Microbiol ; 134(9)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37667489

RESUMO

AIMS: As antimicrobial resistance is on the rise, treating chronic wound infections is becoming more complex. The presence of biofilms in wound beds contributes to this challenge. Here, the activity of a novel hypochlorous acid (HOCl) producing electrochemical bandage (e-bandage) against monospecies and dual-species bacterial biofilms formed by bacteria commonly found in wound infections was assessed. METHODS AND RESULTS: The system was controlled by a wearable potentiostat powered by a 3V lithium-ion battery and maintaining a constant voltage of + 1.5V Ag/AgCl, allowing continuous generation of HOCl. A total of 19 monospecies and 10 dual-species bacterial biofilms grown on polycarbonate membranes placed on tryptic soy agar (TSA) plates were used as wound biofilm models, with HOCl producing e-bandages placed over the biofilms. Viable cell counts were quantified after e-bandages were continuously polarized for 2, 4, 6, and 12 hours. Time-dependent reductions in colony forming units (CFUs) were observed for all studied isolates. After 12 hours, average CFU reductions of 7.75 ± 1.37 and 7.74 ± 0.60 log10 CFU/cm2 were observed for monospecies and dual-species biofilms, respectively. CONCLUSIONS: HOCl producing e-bandages reduce viable cell counts of in vitro monospecies and dual-species bacterial biofilms in a time-dependent manner in vitro. After 12 hours, >99.999% reduction in cell viability was observed for both monospecies and dual-species biofilms.


Assuntos
Ácido Hipocloroso , Infecção dos Ferimentos , Humanos , Ácido Hipocloroso/farmacologia , Bactérias , Bandagens , Biofilmes
6.
Adv Ther (Weinh) ; 6(5)2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37485434

RESUMO

Biofilms formed by antibiotic-resistant bacteria in wound beds present unique challenges in terms of treating wound infections. In this work, the in vivo activity of a novel electrochemical bandage (e-bandage) composed of carbon fabric and controlled by a wearable potentiostat, designed to continuously deliver low amounts of hydrogen peroxide (H2O2) was evaluated against methicillin-resistant Staphylococcus aureus (MRSA), multidrug-resistant Pseudomonas aeruginosa (MDR-PA) and mixed-species (MRSA and MDR-PA) wound infections. Wounds created on Swiss Webster mice were infected with the above-named bacteria and biofilms allowed to establish on wound beds for 3 days. e-Bandages, which electrochemically reduce dissolved oxygen to H2O2 when polarized at -0.6 VAg/AgCl, were placed atop the infected wound bed and polarized continuously for 48 hours. Polarized e-bandage treatment resulted in significant reductions (p <0.001) of both mono-species and mixed-species wound infections. After e-bandage treatment, electron microscopy showed degradation of bacterial cells, and histopathology showed no obvious alteration to the inflammatory host response. Blood biochemistries showed no abnormalities. Taken all together, results of this work suggest that the described H2O2-producing e-bandage can effectively reduce in vivo MRSA, MDR-PA and mixed-species wound biofilms, and should be further developed as a potential antibiotic-free strategy for treatment of wound infections.

7.
Cureus ; 15(3): e36935, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37131573

RESUMO

BACKGROUND:  The incidence and prevalence of heart failure (HF) in the United States has steadily increased in the past few decades. Similarly, the United States has experienced an increase in HF-related hospitalizations which has added to the burden of a resource-stretched healthcare system. With the emergence of the coronavirus disease 2019 (COVID-19) pandemic in 2020, hospitalizations due to the COVID-19 infection sky-rocketed further exacerbating the burden on both patient health and the healthcare system. The focus of this study is to examine how a secondary COVID-19 diagnosis affects the outcome of HF patients, and how a pre-existing diagnosis of heart failure impacts the outcomes of patients hospitalized with COVID-19 infection. METHODS: This was a retrospective observational study of adult patients hospitalized with heart failure and COVID-19 infection in the United States in the years 2019 and 2020. Analysis was conducted using the National Inpatient Sample (NIS) database of the Healthcare Utilization Project (HCUP). The total number of patients included in this study from the NIS database 2020 was 94,745. Of those, 93,798 had heart failure without a secondary diagnosis of COVID-19; 947 had heart failure along with a secondary diagnosis of COVID-19. The primary outcome of our study was in-hospital mortality, length of stay, total hospital charges and time from admission to right heart catheterization, which were compared between the two cohorts.  Results: Our main study findings are that mortality in HF patients with secondary diagnosis of COVID-19 infection was not statistically different compared to those who were without a secondary diagnosis of COVID-19. Our study findings also showed that length of stay (LOS) and hospital costs in HF patients who had a secondary diagnosis of COVID-19 were not statistically different compared to those who did not have the secondary diagnosis. Time from admission to right heart catheterization (RHC) in HF patients who had a secondary diagnosis of COVID-19 was shorter in heart failure with reduced ejection fraction (HFrEF) but not in heart failure preserved ejection fraction (HFpEF) compared to those without secondary diagnoses of COVID-19. Finally, when evaluating hospital outcomes for patients admitted with COVID-19 infection, we found that inpatient mortality increased significantly when they had a pre-existing diagnosis of heart failure. CONCLUSION: The COVID-19 pandemic significantly impacted hospitalization outcomes for patients admitted with heart failure. The time from admission to right heart catheterization was significantly shorter in patients admitted with heart failure reduced ejection fraction who also had a secondary diagnosis of COVID-19 infection. When evaluating hospital outcomes for patients admitted with COVID-19 infection, we found that inpatient mortality increased significantly when they had a pre-existing diagnosis of heart failure. Length of hospital stay and hospital charges also were higher for patients with COVID-19 infection who had pre-existing heart failure. Further studies should focus not just on how medical comorbidities like COVID-19 infection, affect outcomes of heart failure but also on how overall strains on the healthcare system, such as pandemics, may affect the management of conditions such as heart failure.

8.
Adv Eng Mater ; 25(1)2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36817722

RESUMO

Chronic wound biofilm infections represent a major clinical challenge which results in a substantial burden to patients and healthcare systems. Treatment with topical antibiotics is oftentimes ineffective as a result of antibiotic-resistant microorganisms and biofilm-specific antibiotic tolerance. Use of biocides such as hypochlorous acid (HOCl) has gained increasing attention due to the lack of known resistance mechanisms. We designed an HOCl-generating electrochemical bandage (e-bandage) that delivers HOCl continuously at low concentrations targeting infected wound beds in a similar manner to adhesive antimicrobial wound dressings. We developed a battery-operated wearable potentiostat that controls the e-bandage electrodes at potentials suitable for HOCl generation. We demonstrated that e-bandage treatment was tunable by changing the applied potential. HOCl generation on electrode surfaces was verified using microelectrodes. The developed e-bandage showed time-dependent responses against in vitro Acinetobacter baumannii and Staphylococcus aureus biofilms, reducing viable cells to non-detectable levels within 6 and 12 hours of treatment, respectively. The developed e-bandage should be further evaluated as an alternative to topical antibiotics to treat wound biofilm infections.

9.
Antimicrob Agents Chemother ; 67(1): e0116622, 2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36472429

RESUMO

The antibiofilm activity of a hypochlorous acid (HOCl)-producing electrochemical bandage (e-bandage) was assessed against 14 yeast isolates in vitro. The evaluated e-bandage was polarized at +1.5 VAg/AgCl to allow continuous production of HOCl. Time-dependent decreases in the biofilm CFU counts were observed for all isolates with e-bandage treatment. The results suggest that the described HOCl-producing e-bandage could serve as a potential alternative to traditional antifungal wound biofilm treatments.


Assuntos
Ácido Hipocloroso , Saccharomyces cerevisiae , Ácido Hipocloroso/farmacologia , Antifúngicos/farmacologia , Bandagens , Biofilmes
10.
Biotechnol Bioeng ; 120(1): 250-259, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36168277

RESUMO

The activity of a hypochlorous acid-producing electrochemical bandage (e-bandage) in preventing methicillin-resistant Staphylococcus aureus infection (MRSA) infection and removing biofilms formed by MRSA was assessed using a porcine explant biofilm model. e-Bandages inhibited S. aureus infection (p = 0.029) after 12 h (h) of exposure and reduced 3-day biofilm viable cell counts after 6, 12, and 24 h exposures (p = 0.029). Needle-type microelectrodes were used to assess HOCl concentrations in explant tissue as a result of e-bandage treatment; toxicity associated with e-bandage treatment was evaluated. HOCl concentrations in infected and uninfected explant tissue varied between 30 and 80 µM, decreasing with increasing distance from the e-bandage. Eukaryotic cell viability was reduced by an average of 71% and 65% in fresh and day 3-old explants, respectively, when compared to explants exposed to nonpolarized e-bandages. HOCl e-bandages are a promising technology that can be further developed as an antibiotic-free treatment for wound biofilm infections.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecção dos Ferimentos , Suínos , Animais , Ácido Hipocloroso/farmacologia , Staphylococcus aureus , Biofilmes , Bandagens , Infecção dos Ferimentos/prevenção & controle , Antibacterianos/farmacologia
11.
Bioelectrochemistry ; 148: 108261, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36115186

RESUMO

Previously, an electrochemical bandage (e-bandage) that uses a three-electrode system to produce hydrogen peroxide (H2O2) electrochemically on its working electrode was developed as a potential strategy for treating biofilms; it showed activity in reducing biofilms in an agar biofilm model. Xanthan gum-based hydrogel, including NaCl, was used as the electrolyte. While H2O2 generated at the working electrode in the vicinity of a biofilm is a main mechanism of activity, the role of the counter electrode was not explored. The goal of this research was to characterize electrochemical reactions occurring on the counter electrode of the e-bandage. Counter electrode potential varied between 1.2 and 1.5 VAg/AgCl; ∼125 µM hypochlorous acid (HOCl) was generated within 24 h in the e-bandage system. When HOCl was not produced on the counter electrode (achieved by removing NaCl from the hydrogel), reduction of Acinetobacter baumannii BAA-1605 biofilm was 1.08 ± 0.38 log10 CFU/cm2 after 24 h treatment, whereas when HOCl was produced, reduction was 3.87 ± 1.44 log10 CFU/cm2. HOCl inhibited catalase activity, abrogating H2O2 decomposition. In addition to H2O2 generation, the previously described H2O2-generating e-bandage generates HOCl on the counter electrode, enhancing its biocidal activity.


Assuntos
Peróxido de Hidrogênio , Ácido Hipocloroso , Ágar , Bandagens , Catalase , Hidrogéis/farmacologia , Peróxido de Hidrogênio/farmacologia , Ácido Hipocloroso/farmacologia , Cloreto de Sódio
12.
J Appl Microbiol ; 133(6): 3755-3767, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36073322

RESUMO

AIMS: Effects of H2 O2 producing electrochemical-bandages (e-bandages) on methicillin-resistant Staphylococcus aureus colonization and biofilm removal were assessed using a porcine explant biofilm model. Transport of H2 O2 produced from the e-bandage into explant tissue and associated potential toxicity were evaluated. METHODS AND RESULTS: Viable prokaryotic cells from infected explants were quantified after 48 h treatment with e-bandages in three ex vivo S. aureus infection models: (1) reducing colonization, (2) removing young biofilms and (3) removing mature biofilms. H2 O2 concentration-depth profiles in explants/biofilms were measured using microelectrodes. Reductions in eukaryotic cell viability of polarized and nonpolarized noninfected explants were compared. e-Bandages effectively reduced S. aureus colonization (p = 0.029) and reduced the viable prokaryotic cell concentrations of young biofilms (p = 0.029) with limited effects on mature biofilms (p > 0.1). H2 O2 penetrated biofilms and explants and reduced eukaryotic cell viability by 32-44% compared to nonpolarized explants. CONCLUSIONS: H2 O2 producing e-bandages were most active when used to reduce colonization and remove young biofilms rather than to remove mature biofilms. SIGNIFICANCE AND IMPACT OF STUDY: The described e-bandages reduced S. aureus colonization and young S. aureus biofilms in a porcine explant wound model, supporting their further development as an antibiotic-free alternative for managing biofilm infections.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Staphylococcus aureus , Suínos , Animais , Peróxido de Hidrogênio/farmacologia , Biofilmes , Bandagens , Antibacterianos/farmacologia
13.
Healthcare (Basel) ; 10(7)2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35885882

RESUMO

The use of information technology and technological medical devices has contributed significantly to the transformation of healthcare. Despite that, many problems have arisen in diagnosing or predicting diseases, either as a result of human errors or lack of accuracy of measurements. Therefore, this paper aims to provide an integrated health monitoring system to measure vital parameters and diagnose or predict disease. Through this work, the percentage of various gases in the blood through breathing is determined, vital parameters are measured and their effect on feelings is analyzed. A supervised learning model is configured to predict and diagnose based on biometric measurements. All results were compared with the results of the Omron device as a reference device. The results proved that the proposed design overcame many problems as it contributed to expanding the database of vital parameters and providing analysis on the effect of emotions on vital indicators. The accuracy of the measurements also reached 98.8% and the accuracy of diagnosing COVID-19 was 64%. The work also presents a user interface model for clinicians as well as for smartphones using the Internet of things.

14.
Biosens Bioelectron ; 197: 113754, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34773749

RESUMO

Conventional methods for testing antibiotic susceptibility rely on bacterial growth on agar plates (diffusion assays) or in liquid culture (microdilution assays). These time-consuming assays use population growth as a proxy for cellular respiration. Herein we propose to use mediated extracellular electron transfer as a rapid and direct method to classify antibiotic-susceptible and -resistant bacteria. We tested antibiotics with diverse mechanisms of action (ciprofloxacin, imipenem, oxacillin, or tobramycin) with four important nosocomial pathogens (Acinetobacter baumannii, Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae) by adding the bacterial culture to a custom-designed electrochemical cell with a glassy-carbon electrode and growth media supplemented with a soluble electron transfer mediator, phenazine methosulfate (PMS). During cell respiration, liberated electrons reduce PMS, which is then oxidized on the electrode surface, and current is recorded. Using this novel approach, we were able to consistently classify strains as antibiotic-resistant or -susceptible in <90 min for methodology development and <150 min for blinded tests.


Assuntos
Antibacterianos , Técnicas Biossensoriais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias , Diferenciação Celular , Respiração Celular , Elétrons , Testes de Sensibilidade Microbiana
15.
Antimicrob Agents Chemother ; 66(2): e0179221, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34930030

RESUMO

Wound infections are caused by bacteria and/or fungi. The presence of fungal biofilms in wound beds presents a unique challenge, as fungal biofilms may be difficult to eradicate. The goal of this work was to assess the in vitro antibiofilm activity of an H2O2-producing electrochemical bandage (e-bandage) against 15 yeast isolates representing commonly encountered species. Time-dependent decreases in viable biofilm CFU counts of all isolates tested were observed, resulting in no visible colonies with 48 h of exposure by plate culture. Fluorescence microscopic analysis showed extensive cell membrane damage of biofilm cells after e-bandage treatment. Reductions in intracellular ATP levels of yeast biofilm cells were recorded post e-bandage treatment. These results suggest that exposure to H2O2-producing e-bandages reduces in vitro viable cell counts of yeast biofilms, making this a potential new topical treatment approach for fungal wound infections.


Assuntos
Bandagens , Biofilmes , Peróxido de Hidrogênio , Infecção dos Ferimentos , Eletroquímica , Humanos , Peróxido de Hidrogênio/farmacologia , Infecção dos Ferimentos/microbiologia , Infecção dos Ferimentos/prevenção & controle , Leveduras/patogenicidade
16.
Microbiol Spectr ; 9(2): e0055721, 2021 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-34704827

RESUMO

Central line-associated bloodstream infection (CLABSI) contributes to mortality and cost. While aseptic dressings and antibiotic-impregnated catheters prevent some extraluminal infections, intraluminal infections remain a source of CLABSIs. In this proof-of-concept study, an electrochemical intravascular catheter (e-catheter) prototype capable of electrochemically generating hypochlorous acid intraluminally using platinum electrodes polarized at a constant potential of 1.5 electrode potential relative to saturated silver/silver chloride reference electrode measured in volts (VAg/AgCl) was developed. After 24 h of prepolarization at 1.5 VAg/AgCl, their activity was tested against clinical isolates of Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecium, and Escherichia coli derived from catheter-related infections. e-catheters generated a mean HOCl concentration of 15.86 ± 4.03 µM and had a mean pH of 6.14 ± 0.79. E-catheters prevented infections of all four species, with an average reduction of 8.41 ± 0.61 log10 CFU/ml at 48 h compared to controls. Polarized e-catheters which generate low amounts of HOCl continuously should be further developed to prevent intraluminal infection. IMPORTANCE Catheter-related infections constitute an economic and mortality burden in health care. Several options are available to reduce the risk of infection, but only a few focus on preventing intraluminal infection, which occurs in long-term catheters, most often used for dialysis, prolonged treatment, or chemotherapy. A prototype of a catheter called an "e-catheter" composed of three electrodes, capable of producing hypochlorous acid (HOCl) electrochemically in its lumen, was developed. When polarized at 1.5 V, chloride ions in the solution are oxidized to continuously produce low amounts of HOCl, which exhibits antibacterial activity in the lumen of the catheter. Here, this prototype was shown to be able to generate HOCl as well as prevent infection in a preliminary in vitro catheter model. This approach is a potential strategy for catheter infection prevention.


Assuntos
Infecções Relacionadas a Cateter/prevenção & controle , Catéteres , Ácido Hipocloroso/farmacologia , Antibacterianos/farmacologia , Infecções Relacionadas a Cateter/microbiologia , Catéteres/microbiologia , Técnicas Eletroquímicas , Escherichia coli , Feminino , Humanos , Masculino , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/prevenção & controle
17.
Biofilm ; 3: 100055, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34585138

RESUMO

Biofilms formed by antibiotic-resistant bacteria in wound beds present unique challenges in terms of treating chronic wound infections; biofilms formed by one or more than one bacterial species are often involved. In this work, the in vitro anti-biofilm activity of a novel electrochemical bandage (e-bandage) composed of carbon fabric and controlled by a wearable potentiostat, designed to continuously deliver low amounts of hydrogen peroxide (H2O2) was evaluated against 34 mono-species and 12 dual-species membrane bacterial biofilms formed by Staphylococcus aureus, S. epidermidis, Enterococcus faecium, E. faecalis, Streptococcus mutans, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae, Cutibacterium acnes, and Bacteroides fragilis. Biofilms were grown on polycarbonate membranes placed atop agar plates. An e-bandage, which electrochemically reduces dissolved oxygen to H2O2 when polarized at -0.6 VAg/AgCl, was then placed atop each membrane biofilm and polarized continuously for 12, 24, and 48 h using a wearable potentiostat. Time-dependent decreases in viable CFU counts of all mono- and dual-species biofilms were observed after e-bandage treatment. 48 h of e-bandage treatment resulted in an average reduction of 8.17 ± 0.40 and 7.99 ± 0.32 log10 CFU/cm2 for mono- and dual-species biofilms, respectively. Results suggest that the described H2O2 producing e-bandage can reduce in vitro viable cell counts of biofilms grown either in mono- or dual-species forms, and should be further developed as a potential antibiotic-free treatment strategy for treating chronic wound infections.

18.
Biofilm ; 3: 100053, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34308331

RESUMO

The goals of this work were to study the kinetics and investigate the factors controlling the scale up of oxygen reducing mixed culture cathodic biofilms. Cathodic biofilms were enriched on different electrode sizes (14.5 cm2, 40.3 cm2, 131 cm2 and 466 cm2). Biofilm enrichment shifted the oxygen reduction onset potential from -0.1 VAg/AgCl to 0.3 VAg/AgCl, indicating the biofilm catalyzed oxygen reduction. The kinetics of oxygen reduction were studied by varying the bulk dissolved oxygen concentration. Oxygen reduction followed a Michaelis-Menten kinetics on all electrode sizes. The maximum current density decreased with increasing electrode surface area (-97.0 ± 10.6 µA/cm2, -76.0 ± 8.2 µA/cm2, -66.3 ± 3.0 µA/cm2 and -43.5 ± 10.5 µA/cm2, respectively). Cyclic voltammograms suggest that scale up was limited by ohmic resistance, likely due to the low ionic conductivity in the wastewater medium. Mathematical modeling using combined Michaelis-Menten and Butler-Volmer model supports that the decrease in current density with increasing electrode surface area is caused by ohmic losses. Analysis of the microbial community structure in different size electrodes and in multiple regions on the same electrode showed low variability, suggesting that the microbial community does not control the scale up of cathodic biofilms.

19.
Biotechnol Bioeng ; 118(7): 2815-2821, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33856049

RESUMO

Chronic wound infections caused by biofilm-forming microorganisms represent a major burden to healthcare systems. Treatment of chronic wound infections using conventional antibiotics is often ineffective due to the presence of bacteria with acquired antibiotic resistance and biofilm-associated antibiotic tolerance. We previously developed an electrochemical scaffold that generates hydrogen peroxide (H2 O2 ) at low concentrations in the vicinity of biofilms. The goal of this study was to transition our electrochemical scaffold into an H2 O2 -generating electrochemical bandage (e-bandage) that can be used in vivo. The developed e-bandage uses a xanthan gum-based hydrogel to maintain electrolytic conductivity between e-bandage electrodes and biofilms. The e-bandage is controlled using a lightweight, battery-powered wearable potentiostat suitable for use in animal experiments. We show that e-bandage treatment reduced colony-forming units of Acinetobacter buamannii biofilms (treatment vs. control) in 12 h (7.32 ± 1.70 vs. 9.73 ± 0.09 log10 [CFU/cm2 ]) and 24 h (4.10 ± 12.64 vs. 9.78 ± 0.08 log10 [CFU/cm2 ]) treatments, with 48 h treatment reducing viable cells below the limit of detection of quantitative and broth cultures. The developed H2 O2 -generating e-bandage was effective against in vitro A. baumannii biofilms and should be further evaluated and developed as a potential alternative to topical antibiotic treatment of wound infections.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii/crescimento & desenvolvimento , Bandagens , Biofilmes/crescimento & desenvolvimento , Técnicas Eletroquímicas , Peróxido de Hidrogênio , Infecção dos Ferimentos , Infecções por Acinetobacter/microbiologia , Infecções por Acinetobacter/terapia , Animais , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/farmacologia , Infecção dos Ferimentos/microbiologia , Infecção dos Ferimentos/terapia
20.
Artigo em Inglês | MEDLINE | ID: mdl-33649112

RESUMO

Hydrogen peroxide (H2O2) and hypochlorous acid (HOCl) are biocides used for cleaning and debriding chronic wound infections, which often harbor drug resistant bacteria. Here, we evaluated the in vitro activity of H2O2 and HOCl against 27 isolates of eight bacterial species involved in wound infections. Minimum inhibitory concentrations (MICs) and minimum biofilm bactericidal concentrations (MBBCs) were measured. When compared to their respective MICs, MBBCs of isolates exposed to H2O2 were 16- to 1,024-fold higher and those exposed to HOCl were 2- to 4-fold higher. We evaluated selection of resistance after exposure of Staphylococcus aureus and Pseudomonas aeruginosa biofilms to 10 iterations of electrochemically generated HOCl or H2O2 delivered using electrochemical scaffolds (e-scaffolds), observing no decrease in anti-biofilm effects with serial exposure to e-scaffold-generated H2O2 or HOCl. 24-hour exposure to H2O2-generating e-scaffolds consistently decreased colony forming units (CFUs) of S. aureus and P. aeruginosa biofilms by ∼5.0-log10 and ∼4.78-log10 through 10 iterations of exposure, respectively. 4-hour exposure to HOCl-generating e-scaffolds consistently decreased CFUs of S. aureus biofilms by ∼4.9-log10, and 1-hour exposure to HOCl-generating e-scaffolds consistently decreased CFUs of P. aeruginosa biofilms by ∼1.57-log10 These results suggest that HOCl has similar activity against planktonic and biofilm bacteria, whereas the activity of H2O2 is less against biofilm than planktonic bacteria, and that repeat exposure to either biocide, generated electrochemically under the experimental conditions studied, does not lessen antibiofilm effects.

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