Endovascular carotid revascularization under open-chest extracorporeal circulation combined with cardiac surgery in unstable patients at increased risk of carotid-related stroke: SIMultaneous urgent cardiac surgery and MicroNet-covered stent carotid revascularization in extreme-risk patients-SIMGUARD Study.

BACKGROUND: In patients at urgent need for cardiac surgery coexisting with increased-stroke-risk carotid stenosis, any staged intervention increases the risk of complications from the primarily unaddressed pathology. In this challenging cohort, we assessed safety and feasibility of endovascular carotid revascularization under open-chest extracorporeal circulation (ECC) combined with cardiac surgery (hybrid-room true simultaneous treatment). METHODS: Per-protocol (PP), after general anesthesia induction, chest-opening and ECC stand-by installation, carotid stenting (CAS) was performed (femoral/radial or direct carotid access) with ad-hoc/on-hand switch to ECC cardiac surgery. RESULTS: Over 78 months, 60 patients (70.7±6.9years, 85% male, all American Society of Anesthesiology grade IV) were enrolled. All were at increased carotid-related stroke risk (ipsilateral recent stroke/transient ischemick attack, asymptomatic cerebral infarct, increased-risk lesion morphology, bilateral severe stenosis). Majority of study procedures involved CAS+coronary bypass surgery or CAS+valve replacement±coronary bypass. 45 (75%) patients were PP- and 15 (25%) not-PP (NPP-) managed (context therapy). CAS was 100% neuroprotected (transient flow reversal-64.4%, filters-35.6%) and employed micronet-covered plaque-sequestrating stents with routine post-dilatation optimization/embedding. 4 deaths (6.7%) and 7 strokes (11.7%) occurred by 30-days. Despite CAS+surgery performed on aspirin and unfractionated heparin-only (delayed clopidogrel-loading), no thrombosis occurred in the stented arteries, and 30-days stent patency was 100%. NPP-management significantly increased the risk of death/ipsilateral stroke (OR 38.5; P<0.001) and death/any stroke (OR 12.3; P=0.002) by 30-days. CONCLUSIONS: In cardiac unstable patients at increased carotid-related stroke risk who require urgent cardiac surgery, simultaneous cardiac surgery and CAS with micronet-covered stent lesion sequestration is feasible and safe and shows efficacy in minimizing stroke risk. Larger-scale, multicentric evaluation is warranted. (SIMGUARD NCT04973579).

Structural Patterns Enhancing the Antibacterial Activity of Metallacarborane-Based Antibiotics.

Healthcare systems heavily rely on antibiotics to treat bacterial infections, but the widespread presence of multidrug-resistant bacteria puts this strategy in danger. Novel drugs capable of overcoming current resistances are needed if our ability to treat bacterial infections is to be maintained. Boron clusters offer a valuable possibility to create a new class of antibiotics and expand the chemical space of antibiotics beyond conventional carbon-based molecules. In this work, we identified two promising structural patterns providing cobalta bis(dicarbollide)(COSAN)-based compounds with potent and selective activity toward Staphylococcus aureus (including clinical strains): introduction of the α-amino acid amide and addition of iodine directly to the metallacarborane cage. Furthermore, we found that proper hydrophilic-lipophilic balance is crucial for the selective activity of the tested compounds toward S. aureus over mammalian cells. The patterns proposed in this paper can be useful in the development of metallacarborane-based antibiotics with potent antibacterial properties and low cytotoxicity.

How to Improve the Outcomes of LVAD Implantation?

BACKGROUND: Heart transplantation is the treatment of choice for selected patients with end-stage heart failure. Persistent donor organ shortage has resulted in a growing interest in mechanical circulatory support not only as a bridge to transplantation but also as a destination therapy. METHODS: The aim of the study was to analyze the indications, comorbidities, operative technique, complications, and follow-up of all patients undergoing left ventricular assist device implantation in one of the most experienced clinics in Poland between 2015 and 2020 and state the best timing of the procedure. RESULTS: This study included 78 individuals (72 males, 92%; 6 females, 8%) with a median age of 57 years (range, 50-62 years). The median body mass index was 27.12 (range, 25.2-29.5). The etiology of cardiomyopathy was ischemic (n = 31, 39%), dilated cardiomyopathy (n = 47, 60%), and others. Sixty-four patients presented with New York Heart Association class IV (82%). Leading heart rhythm was sinus (n = 31, 40%) and pacemaker rhythm (n = 47, 60%). Sixty-four patients had implantable cardioverter defibrillator implantation (82%). Preoperative echocardiography revealed a median left ventricle ejection fraction of 14.5% (range, 10%-15%) and LV dimension 7.55 cm (range, 6.9-8.275 cm). In 51 patients (65%), imaging confirmed pulmonary hypertension. The intensive care unit stay was 6 days (range, 4.25-11.75 days). Median time to extubation was 25 hours (range, 23.75-70 hours). The median time to discharge was 31.5 days (range, 25-31.85 days). In-hospital mortality was 12 patients (15%). Median follow-up time was 19.5 months (range, 11.25-31 months) months, with the longest follow-up of about 53 months. CONCLUSIONS: Appropriate selection of candidates and timing of left ventricular assist device implantation are critical for improved outcomes of destination therapy.

Outcomes in Patients With HeartMate3 Versus HeartWare Ventricular Assist Device Implanted as Destination Therapy.

BACKGROUND: Donor organ shortage caused a growing interest in mechanical circulatory support not only as a bridge to transplant but also as a destination therapy. Improved results and increased applicability and durability of left ventricular assist devices (LVADs) have established this treatment option as an alternative for patients with end-stage heart failure. METHODS: The aim of the study was to compare the early results, major complications, and the follow up of all patients undergoing HeartMate3 (HM3) LVAD and HeartWare Ventricular Assist Device (HVAD) system implantation in one of the most experienced Clinic in Poland between 2015 and 2020. RESULTS: There were 78 individuals (72 male, 92%; 6 female, 8%), with median age 57 years (range, 50-62 years). Until 2020 we implanted 47 (60%) HVADs and 31 (40%) HM3 LVADs. Patient characteristics were comparable between both groups apart from median left ventricle diameter (8.2 cm [range, 7.4-8.4 cm] in HM3 group vs 7.2 cm [range, 6.7-7.9 cm] in HVAD group; P < .01) The overall survival was 53.2% in the HVAD group and 77.4% in the HM3 group (P =.03). Mean survival time was higher in HM3 group (2.97 years [range, 2.43-3.5 years] vs 2.51 years [range, 1.94-3.08 years]; P < .05). Mean complication-free survival time was also higher in the HM3 group (2.16 years [range, 1.55-2.76] vs 1.61 [range, 1.16-2.06 years]; P < .05), with overall complication-free rate of 54.8% for HM3 vs 29.8% for HVAD (P = .27). Median hospitalization time was comparable (31 days [range, 25-39 days] in the HM3 group vs 32 days [range, 24-38 days] in the HVAD group; P = .49). CONCLUSIONS: Patients supported with the HM3 had significantly fewer major complications than HVAD. Moreover, the HVAD was associated with higher mortality.

Long-term survival following postoperative myocardial infraction after coronary artery bypass surgery.

BACKGROUND: Postoperative myocardial infraction (MI) is a serious complication among patients undergoing Coronary Artery Bypass Grafting (CABG). Data on the impact of postoperative MI on patients undergoing CABG, specifically with respect to their long term outcomes are sparse. METHODS: We retrospectively analyzed all patients who underwent isolated CABG between January 2014 and December 2016 and identified those who fulfilled the definition of the type 5MI following CABG according to the Fourth Universal Definition of Myocardial Infarction. RESULTS: A total of 4,642 CABG patients were identified, of whom 141 (3.04%) were diagnosed with postoperative MI. The mean follow-up time was 5.1±2.07 years (range, 4.4-6.9 years). Postoperative MI was more common in patients with recent acute coronary syndrome, when compared to stable angina (22.8% vs. 31.9%; P=0.011) and in those with non-elective versus planned surgery (28.4% vs. 18.4%; P=0.003). Postoperative MI after CABG was associated with an increased rate of postoperative complications, including cardiac tamponade and re exploration for bleeding. Mortality after postoperative MI was higher at short-term follow-up (up to one year) and long-term follow-up (up to five years). The risk factors for postoperative MI after CABG were incomplete revascularization (IR) [OR (95% CI): 2.25 (1.59-3.12), P=0.001], non-elective surgery [OR (95% CI): 1.68 (1.10-2.54), P=0.015] and female gender [OR (95% CI): 1.48 (1.01-2.18), P=0.045]. CONCLUSIONS: PMI after CABG is associated with reduced short- and long-term survival. The main risk factors for postoperative MI are IR, female gender, and non-elective surgery.

Hybrid techniques for myocardial regeneration: state of the art and future perspectives.

Myocardium has a limited proliferative capacity, and adult hearts are considered incapable of regenerating after injury. A significant loss in the viable myocardium eventually diminishes the heart's ability to contract synchronously, leading to heart failure. Despite the development in interventional and pharmacological treatment for ischemic heart disease and heart failure, there is a significant number of highly symptomatic patients. For these individuals, treatments that stimulate myocardial regeneration can offer alleviation of dyspnea and angina and improvement in quality of life. Stem cells are known to promote neovascularization and endothelial repair. Various stem cell lines have been investigated over the years to establish those with the highest potential to differentiate into cardiomyocytes, including bone marrow-derived mononuclear cells, mesenchymal stromal cells, CD34+, CD133+, endothelial progenitor cells, and adipose-derived mesenchymal stromal cells. Stem cell studies were based on several delivery pathways: infusion into coronary vessels, direct injection into the injured region of the myocardium, and delivery within the novel bioengineered scaffolds. Acellular materials have also been investigated over the years. They demonstrate the therapeutic potential to promote angiogenesis and release of growth factors to improve the restoration of critical components of the extracellular matrix. This review summarizes hybrid cardiac regeneration treatments that combine novel bioengineering techniques with delivery approaches that cardiac surgeons can provide.

Bilateral internal thoracic artery use in two-vessel disease does not increase the perioperative risk-A propensity score matched analysis.

BACKGROUND: Bilateral internal thoracic arteries (BITA) are uncommonly used in the every-day practice due to safety concerns and technical challenges with Y-grafts. We hypothesized that in-situ BITA use during coronary artery by-pass grafting (CABG) for two vessel disease is equally safe to standard strategy with left internal thoracic artery-left anterior descending artery revascularization and venous graft to other target vessels. METHODS: A propensity score matched analysis was used to compare elective on-pump CABG patients who received in-situ BITA (BITA-group), versus left internal thoracic artery graft to the left anterior descending artery plus vein (SITA-group). Primary end points were 30-days all-cause-mortality, major adverse cardiac events and incidents and deep sternal wound infections. RESULTS: A total of 50 matched pairs (c-statistics 0.769) were selected from patients operated on between January 2015 and April 2020 using BITA (n = 50) and SITA (n = 2170). There were no inter-group differences in demographics and basic clinical characteristics. The total operation time was longer in the BITA-group (4.0 vs 3.6 hours; p = 0.004). The rate of complete revascularization was similar, as was median aortic cross-clamp time, median extracorporeal circulation time, rate of re-explorations for bleeding, deep sternal wound infections or length of stay. One patient died in BITA group, 3 days after surgery, from a non-cardiac cause. After 36 months, the survival rate was 98% for BITA-group and 96% for controls (log-rank, p = 0.577). CONCLUSIONS: In-situ use of BITA during coronary revascularization for two-vessel disease is as safe and effective, as use of single ITA and vein graft. In-situ strategy abolishes allows to avoid the technically demanding composite graft configuration.

Early postoperative hemodynamic instability after heart transplantation - incidence and metabolic indicators.

BACKGROUND: Primary graft dysfunction (PGD) is the main cause of death in the first 30 days after heart transplantation (HTX), accounting for approximately 40% of mortality. The study's primary aim was to assess the incidence of PGD, following the International Society for Heart and Lung Transplantation consensus, and to compare it with the incidence of significant postoperative hypotension despite administration of high-dose inotropes and vasoconstrictors. The secondary aim of the study was to determine changes in biochemical markers that accompany the phenomenon. METHODS: Forty-five patients who underwent HTX between 2010 and 2015 were enrolled in this study, and detailed hemodynamic and metabolic data from the first 48 postoperative hours were collected and analyzed. Hemodynamic instability was defined as significant postoperative hypotension (mean arterial pressure (MAP) < 60 mmHg) combined with a high inotrope score (> 10). Data for long-term mortality were obtained from the population registration office. RESULTS: PGD incidence was relatively low (17.8%); however, hemodynamic instability was common (40%). Among unstable patients, MAP was insufficient for end-organ perfusion (51.4 ± 9.5 mmHg) but no decrease in left ventricular function was observed (cardiac index, 2.65 ± 0.6 l/min/m2; left ventricular ejection fraction, 52.9 ± 15.5%). Within this group, mean systemic vascular resistance index (961 ± 288 dyn*s*m2/cm5) was low despite receiving high doses of vasoactive agent (norepinephrine 0.21 (0.06-0.27) µg/kg/min during first 24 h postoperatively and 0.21 (0.01-0.27) µg/kg/min during next 24 h postoperatively). After HTX, serum lactate levels were initially significantly higher in patients with hemodynamic instability (p = 0.002); however, impaired lactate clearance was not observed (p = 0.366), and lactate levels normalized within the first 24 h postoperatively. Postoperative hemodynamic instability altered the long-term outcome and increased 5-year mortality after HTX (p = 0.034). CONCLUSIONS: Hemodynamic instability is a more common phenomenon than PGD. Only early postoperative serum lactate levels correspond with hemodynamic instability following HTX. Postoperative hemodynamic instability is associated with poor long-term survival among HTX recipients.

How Bacteria Change after Exposure to Silver Nanoformulations: Analysis of the Genome and Outer Membrane Proteome.

OBJECTIVE: the main purpose of this work was to compare the genetic and phenotypic changes of E. coli treated with silver nanoformulations (E. coli BW25113 wt, E. coli BW25113 AgR, E. coli J53, E. coli ATCC 11229 wt, E. coli ATCC 11229 var. S2 and E. coli ATCC 11229 var. S7). Silver, as the metal with promising antibacterial properties, is currently widely used in medicine and the biomedical industry, in both ionic and nanoparticles forms. Silver nanoformulations are usually considered as one type of antibacterial agent, but their physical and chemical properties determine the way of interactions with the bacterial cell, the mode of action, and the bacterial cell response to silver. METHODS: the changes in the bacterial genome, resulting from the treatment of bacteria with various silver nanoformulations, were verified by analyzing of genes (selected with mutfunc) and their conservative and non-conservative mutations selected with BLOSUM62. The phenotype was verified using an outer membrane proteome analysis (OMP isolation, 2-DE electrophoresis, and MS protein identification). RESULTS: the variety of genetic and phenotypic changes in E. coli strains depends on the type of silver used for bacteria treatment. The most changes were identified in E. coli ATCC 11229 treated with silver nanoformulation signed as S2 (E. coli ATCC 11229 var. S2). We pinpointed 39 genes encoding proteins located in the outer membrane, 40 genes of their regulators, and 22 genes related to other outer membrane structures, such as flagellum, fimbria, lipopolysaccharide (LPS), or exopolysaccharide in this strain. Optical density of OmpC protein in E. coli electropherograms decreased after exposure to silver nanoformulation S7 (noticed in E. coli ATCC 11229 var. S7), and increased after treatment with the other silver nanoformulations (SNF) marked as S2 (noticed in E. coli ATCC 11229 var. S2). Increase of FliC protein optical density was identified in turn after Ag+ treatment (noticed in E.coli AgR). CONCLUSION: the results show that silver nanoformulations (SNF) exerts a selective pressure on bacteria causing both conservative and non-conservative mutations. The proteomic approach revealed that the levels of some proteins have changed after treatment with appropriate SNF.

OCT Findings in MINOCA.

Myocardial infarction with non-obstructive coronary artery disease (MINOCA) is a working diagnosis for patients presenting with acute myocardial infarction without obstructive coronary artery disease on coronary angiography. It is a heterogenous entity with a number of possible etiologies that can be determined through the use of appropriate diagnostic algorithms. Common causes of a MINOCA may include plaque disruption, spontaneous coronary artery dissection, coronary artery spasm, and coronary thromboembolism. Optical coherence tomography (OCT) is an intravascular imaging modality which allows the differentiation of coronary tissue morphological characteristics including the identification of thin cap fibroatheroma and the differentiation between plaque rupture or erosion, due to its high resolution. In this narrative review we will discuss the role of OCT in patients presenting with MINOCA. In this group of patients OCT has been shown to reveal abnormal findings in almost half of the cases. Moreover, combining OCT with cardiac magnetic resonance (CMR) was shown to allow the identification of most of the underlying mechanisms of MINOCA. Hence, it is recommended that both OCT and CMR can be used in patients with a working diagnosis of MINOCA. Well-designed prospective studies are needed in order to gain a better understanding of this condition and to provide optimal management while reducing morbidity and mortality in that subset patients.

Patterns of Oral Microbiota in Patients with Apical Periodontitis.

In this study, microbial diversity of the root canal microbiota related to different endodontic infections was investigated. In total, 45 patients with endo-perio lesions (8 patients), chronic periapical periodontitis (29 patients) and pulp necrosis (8 patients) were recruited. In 19 (42.2%) patients there was secondary infection of root canals. Microbial specimens were collected from root canals of non-vital teeth with or without changes in periapical area visible in X-ray. Then, oral microbiota were detected and identified using the culture method and real-time PCR amplification primers and hydrolysis-probe detection with the 16S rRNA gene as the target. Overall, 1434 species/genes from 41 different genera of 90 various microbial species were retrieved. Of the major reported phyla, Firmicutes (62.9%), Actinobacteria (14.0%), Bacteroidetes (12.1%), Proteobacteria (9.1%) and Fusobacteria (4.2%) were detected. Of the bacterial species, 54.6% were strict anaerobes. Corynebacterium matruchotii (p = 0.039) was present significantly more frequently in chronic periapical periodontitis. Moreover, the higher values of Decayed, Missing and Filled Permanent Teeth index were positively correlated with relative abundance of Actinomyces spp. (p = 0.042), Lactobacillus spp. (p = 0.006), Propionibacterium spp. (p = 0.024) and Rothia spp. (p = 0.002). The multivariate analyses revealed differences in total root canal samples, where components that affected grouping of root samples into four main categories were identified. Anaerobic Gram-negative bacteria predominated in root canals of teeth with pulp necrosis and periapical lesions. Facultative anaerobic Gram-positive bacteria predominated in canals with secondary infections. All detected members of mixed population groups that might serve as keystone species contributed to the entire community in its clinical relevance.

Comparison of Antibacterial Mode of Action of Silver Ions and Silver Nanoformulations With Different Physico-Chemical Properties: Experimental and Computational Studies.

The aim of this study was to compare the antibacterial mode of action of silver ions (Ag+) and selected silver nanoformulations against E. coli strains (E. coli J53, Escherichia coli BW25113 and its derivatives: Δ ompA, Δ ompC, Δ ompF, Δ ompR, ompRG596AcusSG1130A, cusSG1130A). In this research we used various experimental methods and techniques such as determination of the minimal inhibitory concentration, flow cytometry, scanning electron microscopy, circular dichroism as well as computational methods of theoretical chemistry. Thanks to the processing of bacteria and silver samples (ions and nanoformulations), we were able to determine the bacterial sensitivity to silver samples, detect reactive oxygen species (ROS) in the bacterial cells, visualize the interaction of silver samples with the bacterial cells, and identify their interactions with proteins. Differences between the mode of action of silver ions and nanoformulations and the action of nanoformulations themselves were revealed. Based on the results of computational methods, we proposed an explanation of the differences in silver-outer protein interaction between silver ions and metallic silver; in general, the Ag0 complexes exhibit weaker interaction than Ag+ ones. Moreover, we identified two gutter-like areas of the inner layer of the ion channel: one more effective, with oxygen-rich side chains; and another one less effective, with nitrogen-rich side chains.

Proteomics-based identification of orchid-associated bacteria colonizing the Epipactis albensis, E. helleborine and E. purpurata (Orchidaceae, Neottieae).

Using proteomics-based identification by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), we conducted the first analysis of the composition of endophytic bacteria isolated from different parts of selected Epipactis species, i.e. the buds, the inflorescences and the central part of the shoots, as well as the rhizomes. We identified aerobic and anaerobic bacteria, including such taxa as Bacillus spp., Clostridium spp., Pseudomonas spp. and Stenotrophomonas spp., which may be considered as promoting plant growth. Because most of the indicated bacteria genera belong to spore-producing taxa (spores allow bacterial symbionts to survive adverse conditions), we suggest that these bacteria species contribute to the adaptation of orchids to the environment. We found clear differences in the microbiome between investigated closely related taxa, i.e., Epipactis albensis, E. helleborine, E. purpurata and E. purpurata f. chlorophylla. Some of the analysed orchid species, i.e. E. albensis and E. purpurata co-occur in habitats, and their bacterial microbiomes differ from each other.

The Impact of Graphite Oxide Nanocomposites on the Antibacterial Activity of Serum.

Nanoparticles can interact with the complement system and modulate the inflammatory response. The effect of these interactions on the complement activity strongly depends on physicochemical properties of nanoparticles. The interactions of silver nanoparticles with serum proteins (particularly with the complement system components) have the potential to significantly affect the antibacterial activity of serum, with serious implications for human health. The aim of the study was to assess the influence of graphite oxide (GO) nanocomposites (GO, GO-PcZr(Lys)2-Ag, GO-Ag, GO-PcZr(Lys)2) on the antibacterial activity of normal human serum (NHS), serum activity against bacteria isolated from alveoli treated with nanocomposites, and nanocomposite sensitivity of bacteria exposed to serum in vitro (using normal human serum). Additionally, the in vivo cytotoxic effect of the GO compounds was determined with application of a Galleria mellonella larvae model. GO-PcZr(Lys)2, without IR irradiation enhance the antimicrobial efficacy of the human serum. IR irradiation enhances bactericidal activity of serum in the case of the GO-PcZr(Lys)2-Ag sample. Bacteria exposed to nanocomposites become more sensitive to the action of serum. Bacteria exposed to serum become more sensitive to the GO-Ag sample. None of the tested GO nanocomposites displayed a cytotoxicity towards larvae.

Functional Recovery after Intramyocardial Injection of Adipose-Derived Stromal Cells Assessed by Cardiac Magnetic Resonance Imaging.

AIMS: A major clinical concern is the continuous increase in the number of patients diagnosed with advanced coronary artery disease, ischemic heart failure, and refractory angina, and one of the most promising treatment options for these conditions is stem cell-based therapy. The aim of this study was to assess the functional improvement following intramyocardial injection of adipose-derived stromal cells, using cardiac magnetic resonance. METHODS AND RESULTS: Thirteen patients with ischemic heart failure, reduced left ventricular ejection fraction, refractory angina, and who have been disqualified from any form of direct revascularization were enrolled in the study with transthoracic autologous adipose-derived stromal cell implantation. All patients underwent cardiac magnetic resonance prior to the procedure and after 12 months of follow-up. A significant increase in stroke volume (83.1 ± 8.5 mL vs 93.8 ± 13.8 mL, p = 0.025) and stroke volume index (43.3 ± 7.6 mL/m2 vs 48.7 ± 9.1 mL/m2, p = 0.019), a statistical trend toward an increase in left ventricle ejection fraction (36.7 ± 13.2 vs 39.7 ± 14.9, p = 0.052), and cardiac output improvement (5.0 ± 0.7 vs 5.5 ± 0.9, p = 0.073) was observed in the patient postprocedure. Enhanced relative regional thickening was noted in the segments with adipose-derived stromal cell implantation. CONCLUSIONS: Intramyocardial adipose-derived stromal cell implantation is a promising therapeutic option for selected, symptomatic patients with ischemic heart failure, who have preserved myocardial viability despite being unsuitable for direct revascularization.

Prognostic role of perioperative acid-base disturbances on the risk of Clostridioides difficile infection in patients undergoing cardiac surgery.

BACKGROUND: It is unclear whether acid-base balance disturbances during the perioperative period may impact Clostridium difficile infection (CDI), which is the third most common major infection following cardiac surgery. We hypothesized that perioperative acid-base abnormalities including lactate disturbances may predict the probability of incidence of CDI in patients after cardiac procedures. METHODS: Of the 12,235 analyzed patients following cardiac surgery, 143 (1.2%) developed CDI. The control group included 200 consecutive patients without diarrhea, who underwent cardiac procedure within the same period of observation. Pre-, intra and post-operative levels of blood gases, as well as lactate and glucose concentrations were determined. Postoperatively, arterial blood was drawn four times: immediately after surgery and successively; 4, 8 and 12 h following the procedure. RESULTS: Baseline pH was lower and PaO2 was higher in CDI patients (p < 0.001 and p = 0.001, respectively). Additionally, these patients had greater base deficiency at each of the analyzed time points (p < 0.001, p = 0.004, p = 0.012, p = 0.001, p = 0.016 and p = 0.001, respectively). Severe hyperlactatemia was also more common in CDI patients; during the cardiac procedure, 4 h and 12 h after surgery (p = 0.027, p = 0.004 and p = 0.001, respectively). Multivariate logistic regression analysis revealed that independent risk factors for CDI following cardiac surgery were as follows: intraoperative severe hyperlactatemia (OR 2.387, 95% CI 1.155-4.933, p = 0.019), decreased lactate clearance between values immediately and 12 h after procedure (OR 0.996, 95% CI 0.994-0.999, p = 0.013), increased age (OR 1.045, 95% CI 1.020-1.070, p < 0.001), emergent surgery (OR 2.755, 95% CI 1.565-4.848, p < 0.001) and use of antibiotics other than periprocedural prophylaxis (OR 2.778, 95% CI 1.690-4.565, p < 0.001). CONCLUSION: This study is the first to show that perioperative hyperlactatemia and decreased lactate clearance may be predictors for occurrence of CDI after cardiac surgery.

Benefits of Usage of Immobilized Silver Nanoparticles as Pseudomonas aeruginosa Antibiofilm Factors.

The aim of this study was to assess the beneficial inhibitory effect of silver nanoparticles immobilized on SiO2 or TiO2 on biofilm formation by Pseudomonas aeruginosa-one of the most dangerous pathogens isolated from urine and bronchoalveolar lavage fluid of patients hospitalized in intensive care units. Pure and silver doped nanoparticles of SiO2 and TiO2 were prepared using a novel modified sol-gel method. Ten clinical strains of P. aeruginosa and the reference PAO1 strain were used. The minimal inhibitory concentration (MIC) was determined by the broth microdilution method. The minimal biofilm inhibitory concentration (MBIC) and biofilm formation were assessed by colorimetric assay. Bacterial enumeration was used to assess the viability of bacteria in the biofilm. Silver nanoparticles immobilized on the SiO2 and TiO2 indicated high antibacterial efficacy against P. aeruginosa planktonic and biofilm cultures. TiO2/Ag0 showed a better bactericidal effect than SiO2/Ag0. Our results indicate that the inorganic compounds (SiO2, TiO2) after nanotechnological modification may be successfully used as antibacterial agents against multidrug-resistant P. aeruginosa strains.