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1.
Microorganisms ; 12(4)2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38674650

RESUMEN

This large, multicenter, retrospective cohort study including onco-hematological neutropenic patients with Pseudomonas aeruginosa bloodstream infection (PABSI) found that among 1213 episodes, 411 (33%) presented with septic shock. The presence of solid tumors (33.3% vs. 20.2%, p < 0.001), a high-risk Multinational Association for Supportive Care in Cancer (MASCC) index score (92.6% vs. 57.4%; p < 0.001), pneumonia (38% vs. 19.2% p < 0.001), and infection due to multidrug-resistant P. aeruginosa (MDRPA) (33.8% vs. 21.1%, p < 0.001) were statistically significantly higher in patients with septic shock compared to those without. Patients with septic shock were more likely to receive inadequate empirical antibiotic therapy (IEAT) (21.7% vs. 16.2%, p = 0.020) and to present poorer outcomes, including a need for ICU admission (74% vs. 10.5%; p < 0.001), mechanical ventilation (49.1% vs. 5.6%; p < 0.001), and higher 7-day and 30-day case fatality rates (58.2% vs. 12%, p < 0.001, and 74% vs. 23.1%, p < 0.001, respectively). Risk factors for 30-day case fatality rate in patients with septic shock were orotracheal intubation, IEAT, infection due to MDRPA, and persistent PABSI. Therapy with granulocyte colony-stimulating factor and BSI from the urinary tract were associated with improved survival. Carbapenems were the most frequent IEAT in patients with septic shock, and the use of empirical combination therapy showed a tendency towards improved survival. Our findings emphasize the need for tailored management strategies in this high-risk population.

2.
Antibiotics (Basel) ; 12(11)2023 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-37998822

RESUMEN

Chemically modified carbon nanotubes are recognized as effective materials for tackling bacterial infections. In this study, pristine multi-walled carbon nanotubes (p-MWCNTs) were functionalized with nitric acid (f-MWCNTs), followed by thermal treatment at 600 °C, and incorporated into a poly(dimethylsiloxane) (PDMS) matrix. The materials' textural properties were evaluated, and the roughness and morphology of MWCNT/PDMS composites were assessed using optical profilometry and scanning electron microscopy, respectively. The antibiofilm activity of MWCNT/PDMS surfaces was determined by quantifying culturable Escherichia coli and Staphylococcus aureus after 24 h of biofilm formation. Additionally, the antibacterial mechanisms of MWCNT materials were identified by flow cytometry, and the cytotoxicity of MWCNT/PDMS composites was tested against human kidney (HK-2) cells. The results revealed that the antimicrobial activity of MWCNTs incorporated into a PDMS matrix can be efficiently tailored through nitric acid functionalization, and it can be increased by up to 49% in the absence of surface carboxylic groups in f-MWCNT samples heated at 600 °C and the presence of redox activity of carbonyl groups. MWCNT materials changed the membrane permeability of both Gram-negative and Gram-positive bacteria, while they only induced the production of ROS in Gram-positive bacteria. Furthermore, the synthesized composites did not impact HK-2 cell viability, confirming the biocompatibility of MWCNT composites.

3.
J Mater Chem B ; 11(36): 8697-8716, 2023 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-37646077

RESUMEN

Currently, multidrug-resistant (MDR) infections are one of the most important threats, driving the search for new antimicrobial compounds. Cationic peptide antibiotics (CPAs) and ceragenins (CSAs) contain in their structures cationic groups and adopt a facially amphiphilic conformation, conferring the ability to permeate the membranes of bacteria and fungi. Keeping these features in mind, an amine steroid, DOCA-NH2, was found to be active against reference strains and MDR isolates of Gram-positive Enterococcus faecalis and Staphylococcus aureus and Gram-negative Escherichia coli and Pseudomonas aeruginosa. The compound was active against all the tested microorganisms, having bactericidal and fungicidal activity, displaying minimal inhibitory concentrations (MICs) between 16 and 128 µg mL-1. No synergy with clinically relevant antibacterial drugs was found. However, the compound was able to completely inhibit the biofilm formation of bacteria exposed to the MIC of the compound. For E. coli and E. faecalis, inhibition of biofilm formation occurred at half the MIC. Besides, DOCA-NH2 inhibited the dimorphic transition of Candida albicans at concentrations 4 times lower than the MIC, and can reduce the microorganism virulence and biofilm formation was significantly reduced at both MIC and half the MIC. Polydimethylsiloxane-based coatings containing DOCA-NH2 (0.5, 1.0, and 1.5 wt%) were prepared and tested against the E. coli biofilm formation under hydrodynamic conditions similar to those prevailing in ureteral stents. A biofilm reduction of approximately 80% was achieved when compared to the control.


Asunto(s)
Antiinfecciosos , Acetato de Desoxicorticosterona , Infecciones Urinarias , Humanos , Escherichia coli , Antibacterianos/farmacología , Infecciones Urinarias/tratamiento farmacológico , Aminas , Biopelículas , Cationes
4.
Sci Rep ; 13(1): 6238, 2023 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-37069157

RESUMEN

Polymyxin-carbapenem-resistant Klebsiella pneumoniae (PCR-Kp) with pan (PDR)- or extensively drug-resistant phenotypes has been increasingly described worldwide. Here, we report a PCR-Kp outbreak causing untreatable infections descriptively correlated with bacterial genomes. Hospital-wide surveillance of PCR-Kp was initiated in December-2014, after the first detection of a K. pneumoniae phenotype initially classified as PDR, recovered from close spatiotemporal cases of a sentinel hospital in Rio de Janeiro. Whole-genome sequencing of clinical PCR-Kp was performed to investigate similarities and dissimilarities in phylogeny, resistance and virulence genes, plasmid structures and genetic polymorphisms. A target phenotypic profile was detected in 10% (12/117) of the tested K. pneumoniae complex bacteria recovered from patients (8.5%, 8/94) who had epidemiological links and were involved in intractable infections and death, with combined therapeutic drugs failing to meet synergy. Two resistant bacterial clades belong to the same transmission cluster (ST437) or might have different sources (ST11). The severity of infection was likely related to patients' comorbidities, lack of antimicrobial therapy and predicted bacterial genes related to high resistance, survival, and proliferation. This report contributes to the actual knowledge about the natural history of PCR-Kp infection, while reporting from a time when there were no licensed drugs in the world to treat some of these infections. More studies comparing clinical findings with bacterial genetic markers during clonal spread are needed.


Asunto(s)
Infecciones por Klebsiella , Polimixinas , Humanos , Polimixinas/farmacología , Polimixinas/uso terapéutico , Klebsiella pneumoniae , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/genética , Brasil , Genoma Bacteriano , Brotes de Enfermedades , Carbapenémicos/uso terapéutico , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Pruebas de Sensibilidad Microbiana , beta-Lactamasas/genética , Proteínas Bacterianas/genética
5.
Pathogens ; 11(10)2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36297188

RESUMEN

Objectives: To assess the clinical features and outcomes of Pseudomonas aeruginosa bloodstream infection (PA BSI) in neutropenic patients with hematological malignancies (HM) and with solid tumors (ST), and identify the risk factors for 30-day mortality. Methods: We performed a large multicenter, retrospective cohort study including onco-hematological neutropenic patients with PA BSI conducted across 34 centers in 12 countries (January 2006−May 2018). Episodes occurring in hematologic patients were compared to those developing in patients with ST. Risk factors associated with 30-day mortality were investigated in both groups. Results: Of 1217 episodes of PA BSI, 917 occurred in patients with HM and 300 in patients with ST. Hematological patients had more commonly profound neutropenia (0.1 × 109 cells/mm) (67% vs. 44.6%; p < 0.001), and a high risk Multinational Association for Supportive Care in Cancer (MASCC) index score (32.2% vs. 26.7%; p = 0.05). Catheter-infection (10.7% vs. 4.7%; p = 0.001), mucositis (2.4% vs. 0.7%; p = 0.042), and perianal infection (3.6% vs. 0.3%; p = 0.001) predominated as BSI sources in the hematological patients, whereas pneumonia (22.9% vs. 33.7%; p < 0.001) and other abdominal sites (2.8% vs. 6.3%; p = 0.006) were more common in patients with ST. Hematological patients had more frequent BSI due to multidrug-resistant P. aeruginosa (MDRPA) (23.2% vs. 7.7%; p < 0.001), and were more likely to receive inadequate initial antibiotic therapy (IEAT) (20.1% vs. 12%; p < 0.001). Patients with ST presented more frequently with septic shock (45.8% vs. 30%; p < 0.001), and presented worse outcomes, with increased 7-day (38% vs. 24.2%; p < 0.001) and 30-day (49% vs. 37.3%; p < 0.001) case-fatality rates. Risk factors for 30-day mortality in hematologic patients were high risk MASCC index score, IEAT, pneumonia, infection due to MDRPA, and septic shock. Risk factors for 30-day mortality in patients with ST were high risk MASCC index score, IEAT, persistent BSI, and septic shock. Therapy with granulocyte colony-stimulating factor was associated with survival in both groups. Conclusions: The clinical features and outcomes of PA BSI in neutropenic cancer patients showed some differences depending on the underlying malignancy. Considering these differences and the risk factors for mortality may be useful to optimize their therapeutic management. Among the risk factors associated with overall mortality, IEAT and the administration of granulocyte colony-stimulating factor were the only modifiable variables.

6.
ACS Appl Mater Interfaces ; 14(37): 41779-41789, 2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36053163

RESUMEN

We report on the synthesis of hyaluronan (HA) brush-like copolymers and their application as antagonists of tumorigenic CD44-HA interactions. HA (4.8 kDa, ca. 24 saccharides) was grafted on 2-hydrohyethyl methacrylate (HEMA) by end-on oxime ligation. The obtained copolymers were compared with low and high molecular weight HA in terms of hydrolysis kinetics in the presence of hyaluronidase (isothermal titration calorimetry) and interactions with CD44 (surface plasmon resonance). The results evidenced that the high molecular weight HA and HA-g-HEMA have a much higher affinity to CD44 than low molecular weight HA. Additionally, slower enzymatic degradation was observed for the copolymer, making it an excellent candidate for active targeting of tumorigenic CD44-HA interactions. We, therefore, investigated the effect of the copolymer on cancer cell lines with different expression of CD44 and observed an efficient declustering of CD44 that is usually associated with reduction of metastasis and drug resistance.


Asunto(s)
Neoplasias de la Mama , Ácido Hialurónico , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Femenino , Humanos , Receptores de Hialuranos/metabolismo , Ácido Hialurónico/química , Hialuronoglucosaminidasa/metabolismo , Metacrilatos , Oximas , Polímeros/farmacología
7.
Microorganisms ; 10(4)2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35456784

RESUMEN

To assess the effect of combination antibiotic empirical therapy on 30-day case-fatality rate in neutropenic cancer patients with Pseudomonas aeruginosa (PA) bacteremic pneumonia. This was a multinational, retrospective cohort study of neutropenic onco-hematological patients with PA bloodstream infection (BSI) (2006−2018). The effect of appropriate empirical combination therapy, appropriate monotherapy and inappropriate empirical antibiotic therapy [IEAT] on 30-day case-fatality was assessed only in patients with PA bacteremic pneumonia. Among 1017 PA BSI episodes, pneumonia was the source of BSI in 294 (28.9%). Among those, 52 (17.7%) were caused by a multidrug-resistant (MDR) strain and 68 (23.1%) received IEAT, mainly when the infection was caused by an MDR strain [38/52 (73.1%) vs. 30/242 (12.4%); p < 0.001]. The 30-day case-fatality rate was higher in patients with PA bacteremic pneumonia than in those with PA BSI from other sources (55.1% vs. 31.4%; p < 0.001). IEAT was associated with increased 30-day case-fatality (aHR 1.44 [95%CI 1.01−2.03]; p = 0.042), whereas the use of appropriate combination empirical treatment was independently associated with improved survival (aHR 0.46 [95%CI 0.27−0.78]; p = 0.004). Appropriate empirical monotherapy was not associated with improved overall survival (aHR 1.25 [95%CI 0.76−2.05]; p = 0.39). Combination antibiotic empirical therapy should be administered promptly in febrile neutropenic patients with suspected pneumonia as the source of infection.

8.
Nanomaterials (Basel) ; 12(3)2022 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-35159699

RESUMEN

The increasing incidence of implant-associated infections has prompted the development of effective strategies to prevent biofilm formation on these devices. In this work, pristine graphene nanoplatelet/polydimethylsiloxane (GNP/PDMS) surfaces containing different GNP loadings (1, 2, 3, 4, and 5 wt%) were produced and evaluated on their ability to mitigate biofilm development. After GNP loading optimization, the most promising surface was tested against single- and dual-species biofilms of Staphylococcus aureus and Pseudomonas aeruginosa. The antibiofilm activity of GNP/PDMS surfaces was determined by the quantification of total, viable, culturable, and viable but nonculturable (VBNC) cells, as well as by confocal laser scanning microscopy (CLSM). Results showed that 5 wt% GNP loading reduced the number of total (57%), viable (69%), culturable (55%), and VBNC cells (85%) of S. aureus biofilms compared to PDMS. A decrease of 25% in total cells and about 52% in viable, culturable, and VBNC cells was observed for P. aeruginosa biofilms. Dual-species biofilms demonstrated higher resistance to the antimicrobial activity of GNP surfaces, with lower biofilm cell reductions (of up to 29% when compared to single-species biofilms). Still, the effectiveness of these surfaces in suppressing single- and dual-species biofilm formation was confirmed by CLSM analysis, where a decrease in biofilm biovolume (83% for S. aureus biofilms and 42% for P. aeruginosa and dual-species biofilms) and thickness (on average 72%) was obtained. Overall, these results showed that pristine GNPs dispersed into the PDMS matrix were able to inhibit biofilm growth, being a starting point for the fabrication of novel surface coatings based on functionalized GNP/PDMS composites.

9.
Antibiotics (Basel) ; 12(1)2022 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-36671222

RESUMEN

A clinical-epidemiological score to predict CR-GNB sepsis to guide empirical antimicrobial therapy (EAT), using local data, persists as an unmet need. On the basis of a case-case-control design in a prospective cohort study, the predictive factors for CR-GNB sepsis were previously determined as prior infection, use of mechanical ventilation and carbapenem, and length of hospital stay. In this study, each factor was scored according to the logistic regression coefficients, and the ROC curve analysis determined its accuracy in predicting CR-GNB sepsis in the entire cohort. Among the total of 629 admissions followed by 7797 patient-days, 329 single or recurrent episodes of SIRS/sepsis were enrolled, from August 2015 to March 2017. At least one species of CR-GNB was identified as the etiology in 108 (33%) episodes, and 221 were classified as the control group. The cutoff point of ≥3 (maximum of 4) had the best sensitivity/specificity, while ≤1 showed excellent sensitivity to exclude CR-GNB sepsis. The area under the curve was 0.80 (95% CI: 0.76-0.85) and the number needed to treat was 2.0. The score may improve CR-GNB coverage and spare polymyxins with 22% (95% CI: 17-28%) adequacy rate change. The score has a good ability to predict CR-GNB sepsis and to guide EAT in the future.

10.
Antimicrob Resist Infect Control ; 10(1): 92, 2021 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-34134752

RESUMEN

BACKGROUND: The emergence and spread of antimicrobial resistance and infectious agents have challenged hospitals in recent decades. Our aim was to investigate the circulation of target infectious agents using Geographic Information System (GIS) and spatial-temporal statistics to improve surveillance and control of healthcare-associated infection and of antimicrobial resistance (AMR), using Klebsiella pneumoniae complex as a model. METHODS: A retrospective study carried out in a 450-bed federal, tertiary hospital, located in Rio de Janeiro. All isolates of K. pneumoniae complex from clinical and surveillance cultures of hospitalized patients between 2014 and 2016, identified by the use of Vitek-2 system (BioMérieux), were extracted from the hospital's microbiology laboratory database. A basic scaled map of the hospital's physical structure was created in AutoCAD and converted to QGis software (version 2.18). Thereafter, bacteria according to resistance profiles and patients with carbapenem-resistant K. pneumoniae (CRKp) complex were georeferenced by intensive and nonintensive care wards. Space-time permutation probability scan tests were used for cluster signals detection. RESULTS: Of the total 759 studied isolates, a significant increase in the resistance profile of K. pneumoniae complex was detected during the studied years. We also identified two space-time clusters affecting adult and paediatric patients harbouring CRKp complex on different floors, unnoticed by regular antimicrobial resistance surveillance. CONCLUSIONS: In-hospital GIS with space-time statistical analysis can be applied in hospitals. This spatial methodology has the potential to expand and facilitate early detection of hospital outbreaks and may become a new tool in combating AMR or hospital-acquired infection.


Asunto(s)
Infección Hospitalaria/epidemiología , Farmacorresistencia Bacteriana Múltiple , Sistemas de Información Geográfica , Infecciones por Klebsiella/epidemiología , Brasil , Interpretación Estadística de Datos , Humanos , Klebsiella pneumoniae/efectos de los fármacos , Fenotipo , Estudios Retrospectivos , Análisis Espacio-Temporal , Centros de Atención Terciaria
11.
J Mater Chem B ; 9(17): 3705-3715, 2021 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-33871523

RESUMEN

Hospital-acquired infections are still a major concern worldwide, being frequently related to bacterial biofilm formation on medical devices, and thus difficult to eradicate with conventional antimicrobial treatments. Therefore, infection-preventive solutions based on natural polymers are being investigated. Recently, a marine cyanobacterium-derived polymeric coating (CyanoCoating) has demonstrated great anti-adhesive potential when immobilized onto gold model substrates. In this work, we took this technology a step closer to an industrial application by covalently immobilizing CyanoCoating onto medical grade polyurethane (PU). This immobilization was developed through the introduction of linkable moieties onto a PU inert surface using different pre-treatments. Besides the application of the polydopamine (pDA) linker layer, other processes frequently found in industrial settings, such as atmospheric plasma (using O2 or N2 as reactive gases) and ozone surface activations, were evaluated. From all the pre-treatments tested, the ozone activation was the most promising since the obtained coating not only revealed a homogeneous distribution, but also significantly reduced the adhesion of two relevant etiological bacteria in static conditions (the Gram-positive Staphylococcus aureus and the Gram-negative Escherichia coli). Moreover, it also impaired E. coli biofilm formation under simulated urinary tract dynamic conditions, reinforcing the potential of CyanoCoating as an antibiotic-free alternative to mitigate medical device-associated infections, particularly in the urinary tract.


Asunto(s)
Antiinfecciosos/química , Materiales Biocompatibles Revestidos/química , Cianobacterias/química , Indoles/química , Gases em Plasma/química , Polímeros/química , Poliuretanos/química , Antiinfecciosos/farmacología , Adhesión Bacteriana , Biopelículas , Materiales Biocompatibles Revestidos/metabolismo , Escherichia coli/efectos de los fármacos , Cinética , Nitrógeno/química , Ozono/química , Poliuretanos/metabolismo , Staphylococcus aureus/efectos de los fármacos , Propiedades de Superficie , Temperatura , Factores de Tiempo
12.
iScience ; 24(1): 102001, 2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33490909

RESUMEN

Although high-performance carbon materials are widely used in surface engineering, with emphasis on carbon nanotubes (CNTs), the application of CNT nanocomposites on medical surfaces is poorly documented. In this study, we aimed to evaluate the antimicrobial and anti-adhesive properties of CNT-based surfaces. For this purpose, a PRISMA-oriented systematic review was conducted based on predefined criteria and 59 studies were selected for the qualitative analysis. Results from the analyzed studies suggest that surfaces containing modified CNTs, and specially CNTs conjugated with different polymers, exhibited strong antimicrobial and anti-adhesive activities. These composites seem to preserve the CNT toxicity to microorganisms and promote CNT-cell interactions, as well as to protect them from nonspecific protein adsorption. However, CNTs cannot yet compete with the conventional strategies to fight biofilms as their toxicity profile on the human body has not been thoroughly addressed. This review can be helpful for the development of new engineered medical surfaces.

13.
Antimicrob Resist Infect Control ; 9(1): 132, 2020 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-32795380

RESUMEN

BACKGROUND: Studies have investigated risk factors for infections by specific species of carbapenem-resistant Gram-negative bacilli (CR-GNB), but few considered the group of GNB species and most of them were performed in the setting of bacteremia or hospital infection. This study was implemented to identify risk factors for sepsis by CR- and carbapenem-susceptible (CS) GNB in intensive care unit (ICU) patients to improve management strategies for CR-GNB sepsis. METHODS: We developed a case-case-control study from a prospective cohort of patients with systemic inflammatory response syndrome (SIRS), sepsis-2 or sepsis-3 criteria in which blood and other sample cultures were collected and antimicrobial therapy was instituted, in an adult clinical-surgical ICU, at tertiary public hospital in Rio de Janeiro, from August 2015 through March 2017. RESULTS: Among the total of 629 ICU admissions followed by 7797 patient-days, after applying inclusion and exclusion criteria we identified 184 patients who developed recurrent or single hospital-acquired sepsis. More than 90% of all evaluable cases of sepsis and 87% of control group fulfilled the modified sepsis-3 definition. Non-fermenting bacilli and ventilator-associated pneumonia predominated as etiology and source of CR-GNB sepsis. While Enterobacteriaceae and intra-abdominal surgical site plus urinary-tract infections prevailed in CS-GNB than CR-GNB sepsis. Carbapenemase production was estimated in 76% of CR-GNB isolates. Multivariate logistic regression analysis revealed previous infection (mostly hospital-acquired bacterial infection or sepsis) (OR = 4.28; 95% CI 1.77-10.35), mechanical ventilation (OR = 4.21; 95% CI 1.17-15.18), carbapenem use (OR = 3.42; 95% CI 1.37-8.52) and length of hospital stay (OR = 1.03; 95% CI 1.01-1.05) as independent risk factors for sepsis by CR-GNB. While ICU readmission (OR = 6.92; 95% CI 1.72-27.78) and nosocomial diarrhea (OR = 5.32; 95% CI 1.07-26.45) were factors associated with CS-GNB sepsis. CONCLUSIONS: The investigation of recurrent and not only bacteremic episodes of sepsis was the differential of this study. The results are in agreement with the basic information in the literature. This may help improve management strategies and future studies on sepsis by CR-GNB.


Asunto(s)
Antibacterianos/uso terapéutico , Carbapenémicos/uso terapéutico , Bacterias Gramnegativas/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/sangre , Unidades de Cuidados Intensivos/estadística & datos numéricos , Sepsis/microbiología , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Estudios de Casos y Controles , Enfermedad Crítica , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/microbiología , Femenino , Bacterias Gramnegativas/patogenicidad , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Recurrencia , Factores de Riesgo , Sepsis/tratamiento farmacológico , Centros de Atención Terciaria/estadística & datos numéricos , Adulto Joven
14.
Antibiotics (Basel) ; 9(8)2020 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-32707936

RESUMEN

Different studies have shown that the incorporation of carbon nanotubes (CNTs) into poly(dimethylsiloxane) (PDMS) enables the production of composite materials with enhanced properties, which can find important applications in the biomedical field. In the present work, CNT/PDMS composite materials have been prepared to evaluate the effects of pristine and chemically functionalized CNT incorporation into PDMS on the composite's thermal, electrical, and surface properties on bacterial adhesion in dynamic conditions. Initial bacterial adhesion was studied using a parallel-plate flow chamber assay performed in conditions prevailing in urinary tract devices (catheters and stents) using Escherichia coli as a model organism and PDMS as a control due to its relevance in these applications. The results indicated that the introduction of the CNTs in the PDMS matrix yielded, in general, less bacterial adhesion than the PDMS alone and that the reduction could be dependent on the surface chemistry of CNTs, with less adhesion obtained on the composites with pristine rather than functionalized CNTs. It was also shown CNT pre-treatment and incorporation by different methods affected the electrical properties of the composites when compared to PDMS. Composites enabling a 60% reduction in cell adhesion were obtained by CNT treatment by ball-milling, whereas an increase in electrical conductivity of seven orders of magnitude was obtained after solvent-mediated incorporation. The results suggest even at low CNT loading values (1%), these treatments may be beneficial for the production of CNT composites with application in biomedical devices for the urinary tract and for other applications where electrical conductance is required.

15.
BMJ Open ; 9(5): e025744, 2019 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-31129580

RESUMEN

INTRODUCTION: Pseudomonas aeruginosa (PA) has historically been one of the major causes of severe sepsis and death among neutropenic cancer patients. There has been a recent increase of multidrug-resistant PA (MDRPA) isolates that may determine a worse prognosis, particularly in immunosuppressed patients. The aim of this study is to establish the impact of antibiotic resistance on the outcome of neutropenic onco-haematological patients with PA bacteraemia, and to identify the risk factors for MDRPA bacteraemia and mortality. METHODS AND ANALYSIS: This is a retrospective, observational, multicentre, international study. All episodes of PA bacteraemia occurring in neutropenic onco-haematological patients followed up at the participating centres from 1 January 2006 to 31 May 2018 will be retrospectively reviewed. The primary end point will be overall case-fatality rate within 30 days of onset of PA bacteraemia. The secondary end points will be to describe the following: the incidence and risk factors for multidrug-resistant and extremely drug-resistant PA bacteraemia (by comparing the episodes due to susceptible PA with those produced by MDRPA), the efficacy of ceftolozane/tazobactam, the rates of persistent bacteraemia and bacteraemia relapse and the risk factors for very early (48 hours), early (7 days) and overall (30 days) case-fatality rates. ETHICS AND DISSEMINATION: The Clinical Research Ethics Committee of Bellvitge University Hospital approved the protocol of the study at the primary site. To protect personal privacy, identifying information of each patient in the electronic database will be encrypted. The processing of the patients' personal data collected in the study will comply with the Spanish Data Protection Act of 1998 and with the European Directive on the privacy of data. All data collected, stored and processed will be anonymised. Results will be reported at conferences and in peer-reviewed publications.


Asunto(s)
Bacteriemia/tratamiento farmacológico , Farmacorresistencia Bacteriana Múltiple , Neoplasias/complicaciones , Neutropenia/complicaciones , Infecciones por Pseudomonas/tratamiento farmacológico , Antibacterianos/uso terapéutico , Bacteriemia/mortalidad , Cefalosporinas/uso terapéutico , Humanos , Cooperación Internacional , Modelos Logísticos , Estudios Multicéntricos como Asunto , Estudios Observacionales como Asunto , Pseudomonas aeruginosa/aislamiento & purificación , Proyectos de Investigación , Estudios Retrospectivos , Tazobactam/uso terapéutico , Factores de Tiempo
17.
J Antimicrob Chemother ; 69(11): 3148-55, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25006241

RESUMEN

OBJECTIVES: Invasive aspergillosis (IA) caused by Aspergillus terreus is a significant cause of morbidity and mortality in patients with haematological malignancy (HM). Very few data are available in this patient population to differentiate IA patients with A. terreus from those with non-terreus species of Aspergillus to compare outcomes. We retrospectively investigated 513 HM patients who were treated for either definite or probable IA between June 1993 and August 2012 in a cancer centre. METHODS: We compared baseline characteristics, antifungal therapies and outcomes between patients infected with A. terreus (n = 96, 18.7%) and those infected with non-terreus Aspergillus species (n = 335, 65.3%). Eighty-one patients with mixed or unspecified Aspergillus infections were excluded. RESULTS: Breakthrough infections occurred more frequently in the A. terreus group (91% versus 77%, P = 0.009). A. terreus infection was associated with a lower rate of final response to antifungal therapy (21% versus 38%, P = 0.0015) and a higher rate of IA-associated mortality (51% versus 30%, P < 0.001). Multivariate analyses showed that these associations were independent of patients' clinical characteristics and the antifungal regimens they received. Factors independently associated with final response included treatment with azoles (OR 3.1, 95% CI 1.9-5.0, P < 0.0001) and Aspergillus species (A. terreus versus non-terreus Aspergillus species) (OR 0.5, 95% CI 0.3-0.98, P = 0.043). Additionally, Aspergillus species and treatment with azoles were independently associated with IA-associated mortality. CONCLUSIONS: A. terreus IA in HM patients was associated with worse outcome than IA caused by non-terreus Aspergillus species. Poor prognosis in patients with invasive A. terreus infections is independent of anti-Aspergillus azole-based treatment.


Asunto(s)
Antifúngicos/uso terapéutico , Aspergilosis/tratamiento farmacológico , Aspergillus/aislamiento & purificación , Neoplasias Hematológicas/tratamiento farmacológico , Infecciones Oportunistas/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antifúngicos/farmacología , Aspergilosis/epidemiología , Aspergillus/efectos de los fármacos , Azoles/farmacología , Azoles/uso terapéutico , Niño , Femenino , Neoplasias Hematológicas/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Infecciones Oportunistas/epidemiología , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
18.
Antimicrob Agents Chemother ; 58(5): 2775-80, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24590477

RESUMEN

Although antifungal prophylaxis is frequently administered to patients with acute myeloid leukemia (AML) during remission-induction chemotherapy (RIC), its impact on reducing invasive fungal infections (IFIs) outside clinical trials is rarely reported. We performed a retrospective observational study to identify risk factors for development of IFIs (definite or probable, using revised European Organization for Research and Treatment of Cancer [EORTC] criteria) and all-cause mortality in a cohort of 152 AML patients receiving RIC (2009 to 2011). We also compared rates of IFI and mortality in patients who received echinocandin versus anti-Aspergillus azole (voriconazole or posaconazole) prophylaxis during the first 120 days of RIC. In multivariate analysis, clofarabine-based RIC (hazard ratio [HR], 3.5; 95% confidence interval [CI], 1.5 to 8.3; P = 0.004) and echinocandin prophylaxis (HR, 4.6; 95% CI, 1.8 to 11.9; P = 0.002) were independently associated with higher rates of IFI rates during RIC. Subsequent analysis failed to identify any malignancy- or chemotherapy-related covariates linked to echinocandin prophylaxis that accounted for the higher rates of breakthrough IFI. Although the possibility of other confounding variables cannot be excluded, our findings suggest that echinocandin-based prophylaxis during RIC for AML may be associated with a higher risk of breakthrough IFI.


Asunto(s)
Antifúngicos/uso terapéutico , Aspergillus/efectos de los fármacos , Quimioterapia de Inducción/métodos , Leucemia Mieloide Aguda/tratamiento farmacológico , Anciano , Equinocandinas/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Triazoles/uso terapéutico , Voriconazol/uso terapéutico
19.
Antimicrob Agents Chemother ; 58(2): 865-73, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24277033

RESUMEN

Although primary antifungal prophylaxis (PAP) is routinely administered in patients with acute myeloid leukemia (AML) during remission-induction and consolidation chemotherapy, the impact of PAP on the incidence of invasive fungal infections (IFIs) is not well described. We retrospectively analyzed the incidence of IFIs in 152 patients with AML who had been admitted to a tertiary cancer center between August 2009 and March 2011 and received PAP within 120 days after first remission-induction chemotherapy. We excluded patients who had undergone stem cell transplantation. Patients received a PAP drug with anti-Aspergillus activity during 72% (7,660/10,572) of prophylaxis-days. The incidence of documented IFIs (definite or probable according to revised European Organization for Research and Treatment of Cancer [EORTC] criteria) was 2.0/1,000 prophylaxis-days (95% confidence interval [CI], 1.23 to 3.04). IFIs due to molds were more common than IFIs due to yeasts (1.5/1,000 prophylaxis-days versus 0.4/1,000 prophylaxis-days; P = 0.01). Echinocandin-based PAP (8.6 and 7.1/1,000 prophylaxis-days, respectively) was associated with higher rates of documented IFIs than anti-Aspergillus azoles (voriconazole or posaconazole) (2.4 and 1.1/1,000 prophylaxis-days, respectively) at both 42 days (P = 0.03) and 120 days (P < 0.0001) after first remission-induction chemotherapy. The incidence of overall (documented and presumed) IFIs (P < 0.001), documented IFIs (P < 0.01), and empirical antifungal therapies (P < 0.0001) was higher during the first 42 days than after day 42. Despite the broad use of PAP with anti-Aspergillus activity, IFIs, especially molds, remain a significant cause of morbidity and mortality in AML patients, predominantly during the remission-induction phase. Patients receiving echinocandin-based PAP experienced higher rates of IFIs than did those receiving anti-Aspergillus azoles.


Asunto(s)
Antifúngicos/uso terapéutico , Antineoplásicos/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Micosis/prevención & control , Adulto , Anciano , Anciano de 80 o más Años , Equinocandinas/uso terapéutico , Femenino , Humanos , Leucemia Mieloide Aguda/complicaciones , Leucemia Mieloide Aguda/microbiología , Masculino , Persona de Mediana Edad , Micosis/complicaciones , Micosis/diagnóstico , Micosis/microbiología , Pirimidinas/uso terapéutico , Inducción de Remisión , Estudios Retrospectivos , Prevención Secundaria , Centros de Atención Terciaria , Triazoles/uso terapéutico , Voriconazol
20.
Infect Control Hosp Epidemiol ; 33(8): 845-8, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22759554

RESUMEN

We describe the incidence rates of home healthcare-associated infections (HHAIs) in a pediatric home healthcare service (PHHCS). The overall incidence density of HHAIs was 11.1 infections per 1,000 patient-days. Average incidence density of ventilator-associated pneumonia (VAP) was 6.8 per 1,000 ventilator-days. Strategies for control of VAP should be prioritized in PHHCSs.


Asunto(s)
Servicios de Salud del Niño , Infección Hospitalaria/epidemiología , Servicios de Atención de Salud a Domicilio , Neumonía Asociada al Ventilador/epidemiología , Adolescente , Adulto , Brasil/epidemiología , Niño , Servicios de Salud del Niño/estadística & datos numéricos , Preescolar , Infección Hospitalaria/microbiología , Femenino , Servicios de Atención de Salud a Domicilio/estadística & datos numéricos , Humanos , Incidencia , Lactante , Masculino , Neumonía Asociada al Ventilador/microbiología , Neumonía Asociada al Ventilador/prevención & control , Adulto Joven
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