Novel nanostructured lipid carriers loading Apigenin for anterior segment ocular pathologies.

Dry eye disease (DED) is a chronic multifactorial disorder of the ocular surface caused by tear film dysfunction and constitutes one of the most common ocular conditions worldwide. However, its treatment remains unsatisfactory. While artificial tears are commonly used to moisturize the ocular surface, they do not address the underlying causes of DED. Apigenin (APG) is a natural product with anti-inflammatory properties, but its low solubility and bioavailability limit its efficacy. Therefore, a novel formulation of APG loaded into biodegradable and biocompatible nanoparticles (APG-NLC) was developed to overcome the restricted APG stability, improve its therapeutic efficacy, and prolong its retention time on the ocular surface by extending its release. APG-NLC optimization, characterization, biopharmaceutical properties and therapeutic efficacy were evaluated. The optimized APG-NLC exhibited an average particle size below 200 nm, a positive surface charge, and an encapsulation efficiency over 99 %. APG-NLC exhibited sustained release of APG, and stability studies demonstrated that the formulation retained its integrity for over 25 months. In vitro and in vivo ocular tolerance studies indicated that APG-NLC did not cause any irritation, rendering them suitable for ocular topical administration. Furthermore, APG-NLC showed non-toxicity in an epithelial corneal cell line and exhibited fast cell internalization. Therapeutic benefits were demonstrated using an in vivo model of DED, where APG-NLC effectively reversed DED by reducing ocular surface cellular damage and increasing tear volume. Anti-inflammatory assays in vivo also showcased its potential to treat and prevent ocular inflammation, particularly relevant in DED patients. Hence, APG-NLC represent a promising system for the treatment and prevention of DED and its associated inflammation.

How do we diagnose acute diverticulitis? Results of a national survey about the role of imaging techniques.

INTRODUCTION: The choice of imaging techniques in the diagnosis of acute diverticulitis is controversial. This study aimed to determine radiologists' preferences for different imaging techniques in the management of acute diverticulitis and the extent to which they use the different radiologic techniques for this purpose. METHODS: An online survey was disseminated through the Spanish Society of Abdominal Imaging (Sociedad Española de Diagnóstico por Imagen del Abdomen (SEDIA)) and Twitter. The survey included questions about respondents' working environments, protocolization, personal preferences, and actual practice in the radiological management of acute diverticulitis. RESULTS: A total of 186 responses were obtained, 72% from radiologists working in departments organized by organ/systems. Protocols for managing acute diverticulitis were in force in 48% of departments. Ultrasonography was the initial imaging technique in 47.5%, and 73% of the respondents considered that ultrasonography should be the first-choice technique; however, in practice, ultrasonography was the initial imaging technique in only 24% of departments. Computed tomography was the first imaging technique in 32.8% of departments, and its use was significantly more common outside normal working hours. The most frequently employed classification was the Hinchey classification (75%). Nearly all (96%) respondents expressed a desire for a consensus within the specialty about using the same classification. Hospitals with >500 beds and those organized by organ/systems had higher rates of protocolization, use of classifications, and belief that ultrasonography is the best first-line imaging technique. CONCLUSIONS: The radiologic management of acute diverticulitis varies widely, with differences in the protocols used, radiologists' opinions, and actual clinical practice.

Classification of acute diverticulitis in the left colon with ultrasonography and computed tomography: Value of current severity classification schemes.

BACKGROUND AND AIMS: The current management of acute diverticulitis of the left colon (ADLC) requires tests with high prognostic value. This paper analyzes the usefulness of ultrasonography (US) in the initial diagnosis of ADLC and the validity of current classifications schemes for ADLC. PATIENTS: This retrospective observational study included patients with ADLC scheduled to undergo US or computed tomography (CT) following a clinical algorithm. According to the imaging findings, ADLC was classified as mild, locally complicated, or complicated. We analyzed the efficacy of US in the initial diagnosis and the reasons why CT was used as the first-line technique. We compared the findings with published classifications schemes for ADLC. RESULTS: A total of 311 patients were diagnosed with acute diverticulitis; 183 had ADLC, classified at imaging as mild in 104, locally complicated in 60, and complicated in 19. The diagnosis was reached by US alone in 98 patients, by CT alone in 77, and by combined US and CT in 8. The main reasons for using CT as the first-line technique were the radiologist's lack of experience in abdominal US and the unavailability of a radiologists on call. Six patients diagnosed by US were reexamined by CT, but the classification changed in only three. None of the published classification schemes included all the imaging findings. CONCLUSIONS: US should be the first-line imaging technique in patients with suspected ADLC. Various laboratory and imaging findings are useful in establishing the prognosis of ADLC. New schemes to classify the severity of ADLC are necessary to ensure optimal clinical decision making.

Anticoagulation strategies and risk of bleeding events in critically ill COVID-19 patients.

OBJECTIVE: To evaluate the rate of thrombosis, bleeding and mortality comparing anticoagulant doses in critically ill COVID-19 patients. DESIGN: Retrospective observational and analytical cohort study. SETTING: COVID-19 patients admitted to the intensive care unit of a tertiary hospital between March and April 2020. PATIENTS: 201 critically ill COVID-19 patients were included. Patients were categorized into three groups according to the highest anticoagulant dose received during hospitalization: prophylactic, intermediate and therapeutic. INTERVENTIONS: The incidence of venous thromboembolism (VTE), bleeding and mortality was compared between groups. We performed two logistic multivariable regressions to test the association between VTE and bleeding and the anticoagulant regimen. MAIN VARIABLES OF INTEREST: VTE, bleeding and mortality. RESULTS: 78 patients received prophylactic, 94 intermediate and 29 therapeutic doses. No differences in VTE and mortality were found, while bleeding events were more frequent in the therapeutic (31%) and intermediate (15%) dose group than in the prophylactic group (5%) (p<0.001 and p<0.05 respectively). The anticoagulant dose was the strongest determinant for bleeding (odds ratio 2.4, 95% confidence interval 1.26-4.58, p=0.008) but had no impact on VTE. CONCLUSIONS: Intermediate and therapeutic doses appear to have a higher risk of bleeding without a decrease of VTE events and mortality in critically ill COVID-19 patients.

Interhospital Sepsis Code in Catalonia (Spain): Territorial model for initial care of patients with sepsis. / Código Sepsis Interhospitalario en Catalunya: modelo organizativo territorial para la atención inicial al paciente con sepsis.

Sepsis is a syndromic entity with high prevalence and mortality. The management of sepsis is standardized and exhibits time-dependent efficiency. However, the management of patients with sepsis is complex. The heterogeneity of the forms of presentation can make it difficult to detect and manage such cases, in the same way as differences in training, professional competences or the availability of health resources. The Advisory Commission for Patient Care with Sepsis (CAAPAS), comprising 7 scientific societies, the Emergency Medical System (SEM) and the Catalan Health Service (CatSalut), have developed the Interhospital Sepsis Code (CSI) in Catalonia (Spain). The general objective of the CSI is to increase awareness, promote early detection and facilitate initial care and interhospital coordination to attend septic patients in a homogeneous manner throughout Catalonia.

Polycaprolactone/gelatin-based scaffolds with tailored performance: in vitro and in vivo validation.

Nanofibrous scaffolds composed of polycaprolactone (PCL) and gelatin (Ge) were obtained through a hydrolytic assisted electrospinning process. The PCL-to-Ge proportion (100/0 to 20/80), as well as the dissolution time (24, 48, 72, 96, 120 h) into a 1:1 formic/acetic acid solvent before electrospinning were modified to obtain the different samples. A strong influence of these factors on the physicochemical properties of the scaffolds was observed. Higher Ge percentage reduced crystallinity, allowed a uniform morphology and increased water contact angle. The increase in the dissolution time considerably reduced the molar mass and, subsequently, fibre diameter and crystallinity were affected. During in vitro biocompatibility tests, higher cell adhesion and proliferation were found for the 60/40, 50/50 and 40/60 PCL/Ge compositions that was corroborated by MTT assay, fluorescence and microscopy. A weakened structure, more labile to the in vitro degradation in physiologic conditions was found for these compositions with higher dissolution times (72 and 96 h). Particularly, the 40/60 PCL/Ge scaffolds revealed an interesting progressive degradation behaviour as a function of the dissolution time. Moreover, these scaffolds were non-inflammatory, as revealed by the pyrogen test and after the 15-day subcutaneous in vivo implantation in mice. Finally, a reduction of the scar tissue area after infarction was found for the 40/60 PCL/Ge scaffolds electrospun after 72 h implanted in rat hearts. These results are especially interesting and represent a feasible way to avoid undesired inflammatory reactions during the scaffold assimilation.

Preoperative oral antibiotic prophylaxis reduces Pseudomonas aeruginosa surgical site infections after elective colorectal surgery: a multicenter prospective cohort study.

BACKGROUND: Healthcare-associated infections caused by Pseudomonas aeruginosa are associated with poor outcomes. However, the role of P. aeruginosa in surgical site infections after colorectal surgery has not been evaluated. The aim of this study was to determine the predictive factors and outcomes of surgical site infections caused by P. aeruginosa after colorectal surgery, with special emphasis on the role of preoperative oral antibiotic prophylaxis. METHODS: We conducted an observational, multicenter, prospective cohort study of all patients undergoing elective colorectal surgery at 10 Spanish hospitals (2011-2014). A logistic regression model was used to identify predictive factors for P. aeruginosa surgical site infections. RESULTS: Out of 3701 patients, 669 (18.1%) developed surgical site infections, and 62 (9.3%) of these were due to P. aeruginosa. The following factors were found to differentiate between P. aeruginosa surgical site infections and those caused by other microorganisms: American Society of Anesthesiologists' score III-IV (67.7% vs 45.5%, p = 0.001, odds ratio (OR) 2.5, 95% confidence interval (95% CI) 1.44-4.39), National Nosocomial Infections Surveillance risk index 1-2 (74.2% vs 44.2%, p < 0.001, OR 3.6, 95% CI 2.01-6.56), duration of surgery ≥75thpercentile (61.3% vs 41.4%, p = 0.003, OR 2.2, 95% CI 1.31-3.83) and oral antibiotic prophylaxis (17.7% vs 33.6%, p = 0.01, OR 0.4, 95% CI 0.21-0.83). Patients with P. aeruginosa surgical site infections were administered antibiotic treatment for a longer duration (median 17 days [interquartile range (IQR) 10-24] vs 13d [IQR 8-20], p = 0.015, OR 1.1, 95% CI 1.00-1.12), had a higher treatment failure rate (30.6% vs 20.8%, p = 0.07, OR 1.7, 95% CI 0.96-2.99), and longer hospitalization (median 22 days [IQR 15-42] vs 19d [IQR 12-28], p = 0.02, OR 1.1, 95% CI 1.00-1.17) than those with surgical site infections due to other microorganisms. Independent predictive factors associated with P. aeruginosa surgical site infections were the National Nosocomial Infections Surveillance risk index 1-2 (OR 2.3, 95% CI 1.03-5.40) and the use of oral antibiotic prophylaxis (OR 0.4, 95% CI 0.23-0.90). CONCLUSIONS: We observed that surgical site infections due to P. aeruginosa are associated with a higher National Nosocomial Infections Surveillance risk index, poor outcomes, and lack of preoperative oral antibiotic prophylaxis. These findings can aid in establishing specific preventive measures and appropriate empirical antibiotic treatment.

Multistate modelling to estimate excess length of stay and risk of death associated with organ/space infection after elective colorectal surgery.

BACKGROUND: Accounting for time-dependency and competing events are strongly recommended to estimate excess length of stay (LOS) and risk of death associated with healthcare-associated infections. AIM: To assess the effect of organ/space (OS) surgical site infection (SSI) on excess LOS and in-hospital mortality in patients undergoing elective colorectal surgery (ECS). METHODS: A multicentre prospective adult cohort undergoing ECS, January 2012 to December 2014, at 10 Spanish hospitals was used. SSI was considered the time-varying exposure and defined as incisional (superficial and deep) or OS. Discharge alive and death were the study endpoints. The mean excess LOS was estimated using a multistate model which provided a weighted average based on the states patients passed through. Multivariate Cox regression models were used to assess the effect of OS-SSI on risk of discharge alive or in-hospital mortality. FINDINGS: Of 2778 patients, 343 (12.3%) developed SSI: 194 (7%) OS-SSI and 149 (5.3%) incisional SSI. Compared to incisional SSI or no infection, OS-SSI prolonged LOS by 4.2 days (95% confidence interval (CI): 4.1-4.3) and 9 days (8.9-9.1), respectively, reduced the risk of discharge alive (adjusted hazard ratio (aHR): 0.36 (95% CI: 0.28-0.47) and aHR: 0.17 (0.14-0.21), respectively), and increased the risk of in-hospital mortality (aHR: 8.02 (1.03-62.9) and aHR: 10.7 (3.7-30.9), respectively). CONCLUSION: OS-SSI substantially extended LOS and increased risk of death in patients undergoing ECS. These results reinforce OS-SSI as the SSI with the highest health burden in ECS.

Predictive factors for early- and late-onset surgical site infections in patients undergoing elective colorectal surgery. A multicentre, prospective, cohort study.

BACKGROUND: Surgical site infections (SSIs) are the leading cause of healthcare-associated infections in acute care hospitals in Europe. However, the risk factors for the development of early-onset (EO) and late-onset (LO) SSI have not been elucidated. AIM: This study investigated the predictive factors for EO-SSI and LO-SSI in a large cohort of patients undergoing colorectal surgery. METHODS: We prospectively followed-up adult patients undergoing elective colorectal surgery in 10 hospitals (2011-2014). Patients were divided into three groups: EO-SSI, LO-SSI, or no infection (no-SSI). The cut-off defining EO-SSI and LO-SSI was seven days (median time to SSI development). Different predictive factors for EO-SSI and LO-SSI were analysed, comparing each group with the no-SSI patients. FINDINGS: Of 3701 patients, 320 (8.6%) and 349 (9.4%) developed EO-SSI and LO-SSI, respectively. The rest had no-SSI. Patients with EO-SSI were mostly males, had colon surgery and developed organ-space SSI whereas LO-SSI patients frequently received chemotherapy or radiotherapy and had incisional SSI. Male sex (odds ratio (OR): 1.92; P < 0.001), American Society of Anesthesiologists' physical status >2 (OR: 1.51; P = 0.01), administration of mechanical bowel preparation (OR: 0.7; P = 0.03) and stoma creation (OR: 1.95; P < 0.001) predicted EO-SSI whereas rectal surgery (OR: 1.43; P = 0.03), prolonged surgery (OR: 1.4; P = 0.03) and previous chemotherapy (OR: 1.8; P = 0.03) predicted LO-SSI. CONCLUSION: We found distinctive predictive factors for the development of SSI before and after seven days following elective colorectal surgery. These factors could help establish specific preventive measures in each group.

Impact of surgical site infection on healthcare costs and patient outcomes: a systematic review in six European countries.

BACKGROUND: Surgical site infections (SSIs) are associated with increased morbidity and mortality. Furthermore, SSIs constitute a financial burden and negatively impact on patient quality of life (QoL). AIM: To assess, and evaluate the evidence for, the cost and health-related QoL (HRQoL) burden of SSIs across various surgical specialties in six European countries. METHODS: Electronic databases and conference proceedings were systematically searched to identify studies reporting the cost and HRQoL burden of SSIs. Studies published post 2005 in France, Germany, the Netherlands, Italy, Spain, and the UK were eligible for data extraction. Studies were categorized by surgical specialty, and the primary outcomes were the cost of infection, economic evaluations, and HRQoL. FINDINGS: Twenty-six studies met the eligibility criteria and were included for analysis. There was a paucity of evidence in the countries of interest; however, SSIs were consistently associated with elevated costs, relative to uninfected patients. Several studies reported that SSI patients required prolonged hospitalization, reoperation, readmission, and that SSIs increased mortality rates. Only one study reported QoL evidence, the results of which demonstrated that SSIs reduced HRQoL scores (EQ-5D). Hospitalization reportedly constituted a substantial cost burden, with additional costs arising from medical staff, investigation, and treatment costs. CONCLUSION: Disparate reporting of SSIs makes direct cost comparisons difficult, but this review indicated that SSIs are extremely costly. Thus, rigorous procedures must be implemented to minimize SSIs. More economic and QoL studies are required to make accurate cost estimates and to understand the true burden of SSIs.

A three-dimensional self-opening intraneural peripheral interface (SELINE).

OBJECTIVE: In this study we present the development and testing in a rat model of the self-opening neural interface (SELINE), a novel flexible peripheral neural interface. APPROACH: This polyimide-based electrode has a three-dimensional structure that provides an anchorage system to the nerve and confers stability after implant. This geometry has been achieved by means of the plastic deformation of polyimide. Mechanical and electrochemical characterizations have been performed to prove the integrity of the electrode with very good results. Functionality of SELINEs for fascicular stimulation has been tested during in vivo acute experiments in the rat. Chronic implants were made to test the biocompatibility of the device. MAIN RESULTS: Results showed that SELINEs significantly improve mechanical anchorage to the nerve. Stimulation stability is considerably enhanced compared to common planar transversal electrodes and stimulation selectivity is increased for some motor fascicles. Chronic experimental results showed that SELINEs neither produce changes in the fascicular organization of sciatic nerves nor signs of nerve degeneration. SIGNIFICANCE: The presented three-dimensional electrode provides an effective anchorage system to the nervous tissue that can improve the stability of the implant for acute and chronic studies.

Post-discharge surgical site infections after uncomplicated elective colorectal surgery: impact and risk factors. The experience of the VINCat Program.

BACKGROUND: Surgical site infection (SSI) after colorectal procedures represents a measurable quality indicator of a healthcare system. There is an increasing interest in comparing SSI rates between different hospitals and countries: however, the variability of the data regarding the incidence of SSI makes this comparison difficult. For the purposes of evaluation, data collection must be standardized and must include reliable post-discharge surveillance (PDS). AIM: To determine impact and risk factors for PDS SSI after elective colorectal surgery. METHODS: VINCat is a nosocomial infection surveillance programme in Catalonia, Spain. Between 2007 and 2011, 52 hospitals joined the programme. Hospitals performed active, prospective, standardized surveillance of elective colorectal resection. PDS was implemented by a multimodal approach and was mandatory within the first 30 days after surgery. FINDINGS: During the study period, 13,661 elective colorectal procedures were included. SSI was diagnosed in 2826 (20.7%) patients, of whom 22.5% during PDS; of these, 52% required readmission. Patients with PDS SSI were younger (odds ratio: 1.57; 95% confidence interval: 1.29-1.91), predominantly female (1.40; 1.16-1.69), had more frequently undergone endoscopic procedures (1.56; 1.30-1.88) and had more incisional SSI (1.88; 1.54-2.28) than patients with in-hospital SSI. CONCLUSION: SSI rates in elective colorectal procedures at VINCat hospitals were inside the higher range of those reported by other national programmes. PDS SSI increased the overall rate of SSI, had a significant clinical impact, and accounted for almost a quarter of SSI. Younger age and laparoscopic procedures were the most relevant risk factors. Standardized multimodal PDS should be implemented for hospitals performing surveillance of colorectal surgery.

Reprocessed polylactide: studies of thermo-oxidative decomposition.

The combustion process of virgin and reprocessed polylactide (PLA) was simulated by multi-rate linear non-isothermal thermogravimetric experiments under O(2). A complete methodology that accounted on the thermal stability and emission of gases was thoroughly developed. A new model, Thermal Decomposition Behavior, and novel parameters, the Zero-Decomposition Temperatures, were used to test the thermal stability of the materials under any linear heating rate. The release of gases was monitored by Evolved Gas Analysis with in-line FT-IR analysis. In addition, a kinetic analysis methodology that accounted for variable activation parameters showed that the decomposition process could be driven by the formation of bubbles in the melt. It was found that the combustion technologies for virgin PLA could be transferred for the energetic valorization of its recyclates. Combustion was pointed out as appropriate for the energetic valorization of PLA submitted to more than three successive reprocessing cycles.

A methodology to assess the energetic valorization of bio-based polymers from the packaging industry: pyrolysis of reprocessed polylactide.

The energetic valorization process of bio-based polymers is addressed in this study, taking polylactide (PLA) as model. The pyrolysis of virgin and multiple-injected PLA was simulated by means of multi-rate linear-non-isothermal thermogravimetric experiments. A complete methodology, involving control of gases, thermal stability and thermal decomposition kinetics was proposed. The release of gases was monitored by Evolved Gas Analysis of the fumes of pyrolysis, by in-line FT-IR, with the aid of 2D-correlation IR characterization. A novel model to establish the thermal stability of PLAs under any linear heating profile was proposed. A kinetic strategy was methodically applied to assess the thermal decomposition in terms of activation energy and kinetic model. It was found that the pyrolysis technologies for virgin PLA could be straightforwardly transferred for the valorization of its recyclates.

[Fiberoptic bronchoscopy in a respiratory intensive care unit]. / Fibrobroncoscopia en una unidad de vigilancia intensiva respiratoria.

OBJECTIVE: To describe the indications, diagnostic performance and safety of fiberoptic bronchoscopy (FOB) performed in a respiratory intensive care unit (RICU). DESIGN: A prospective, observational study was carried out. SETTING: A 6-bed RICU in a tertiary university hospital. PATIENTS: Patients admitted to RICU who required FOB. INTERVENTIONS: None. MAIN MEASUREMENTS: FOB indications and complications, endoscopic procedures, time required to perform FOB. RESULTS: Sixty-nine out (23%) of the 297 patients admitted to the RICU underwent a total of 107 FOB. Sixty-eight percent of FOB were performed in patients on mechanical ventilation. FOB was performed for diagnostic and therapeutic purposes in 88 (82%) and 19 cases (18%), respectively. The study of pulmonary infiltrates was the main indication for diagnostic FOB (44 cases; 50%), particularly in immunocompromised patients (24 cases; 27%). In immunocompromised patients the diagnostic performance of FOB was significantly higher than in immunocompetent subjects (48% vs 30%; p<0.01). No major complications were recorded. Only a significant drop in PaO(2)/FiO(2) ratio was observed (182 ± 74 vs 163 ± 79; p<0.005) in patients undergoing bronchoalveolar lavage. Overall mortality in patients in the RICU was 14%. In patients requiring a single FOB procedure, mortality was 25%, versus 45% among those requiring more than one FOB procedure. CONCLUSIONS: These results show that FOB is used commonly in the RICU. It is a safe and fast procedure that contributes significantly to clinical management. Patients requiring additional FOB during admission to the RICU show high mortality.

A statistical design of experiments for optimizing the MALDI-TOF-MS sample preparation of polymers. An application in the assessment of the thermo-mechanical degradation mechanisms of poly (ethylene terephthalate).

The sample preparation procedure for MALDI-TOF MS of polymers is addressed in this study by the application of a statistical Design of Experiments (DoE). Industrial poly (ethylene terephthalate) (PET) was chosen as model polymer. Different experimental settings (levels) for matrixes, analyte/matrix proportions and concentrations of cationization agent were considered. The quality parameters used for the analysis were signal-to-noise ratio and resolution. A closer inspection of the statistical results provided the study not only with the best combination of factors for the MALDI sample preparation, but also with a better understanding of the influence of the different factors, individually or in combination, to the signal. The application of DoE for the improvement of the MALDI measure of PET stated that the best combination of factors and levels was the following: matrix (dithranol), proportion analyte/matrix/cationization agent (1/15/1, V/V/V), and concentration of cationization agent (2 g L(-1)). In a second part, multiple processing by means of successive injection cycles was used to simulate the thermo-mechanical degradation effects on the oligomeric distribution of PET under mechanical recycling. The application of MALDI-TOF-MS showed that thermo-mechanical degradation primarily affected initially predominant cyclic species. Several degradation mechanisms were proposed, remarking intramolecular transesterification and hydrolysis. The ether links of the glycol unit in PET were shown to act as potential reaction sites, driving the main reactions of degradation.

[Recommendations in the empiric anti-infective agents of intra-abdominal infection]. / Recomendaciones en el tratamiento antibiótico empírico de la infección intraabdominal.

A significant number of patients with abdominal infection develop advanced stages of infection and mortality is still above 20%. Failure is multifactorial and is associated with an increase of bacterial resistance, inappropriate empirical treatment, a higher comorbidity of patients and poor source control of infection. These guidelines discuss each of these problems and propose measures to avoid the failure based on the best current scientific evidence.

Role of secreted glyceraldehyde-3-phosphate dehydrogenase in the infection mechanism of enterohemorrhagic and enteropathogenic Escherichia coli: interaction of the extracellular enzyme with human plasminogen and fibrinogen.

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) (EC 1.2.1.12) is an anchorless, multifunctional protein displayed on the surface of several fungi and Gram-positive pathogens, which contributes to their adhesion and virulence. To date a role for extracellular GAPDH in the pathogenesis of Gram-negative bacteria has not been described. The aim of this study was to analyze the extracellular localization of GAPDH in enterohemorrhagic (EHEC) and enteropathogenic (EPEC) Escherichia coli strains and to examine its interaction with host components that could be related to the infection mechanism. Recombinant E. coli GAPDH was purified and polyclonal antibodies were obtained. Western blotting and immunoelectron microscopy showed that GAPDH is located on the bacterial surface and released to the culture medium of EHEC and EPEC strains. GAPDH export in these Gram-negative pathogens depends on the external medium, is not mediated by vesicles and leads to an extracellular active enzyme. Non-pathogenic E. coli strains do not secrete GAPDH. Two-dimensional electrophoresis analysis showed that in E. coli GAPDH is present at least in two major forms with different isoelectric points. Of these forms, the more basic is secreted. Purified GAPDH was found to bind human plasminogen and fibrinogen in Far-Western blot and ELISA-based assays. In addition, GAPDH remained associated with colonic Caco-2 epithelial cells after adhesion of EHEC or EPEC. These observations indicate that exported GAPDH may act as a virulence factor which could contribute to EHEC and EPEC pathogenesis. This is the first description of an extracellular localization for this enzyme, with a function other than its glycolytic role in Gram-negative pathogens.