[Management of infectious complications associated with coronavirus infection in severe patients admitted to ICU]. / Manejo de las complicaciones infecciosas asociadas con la infección por coronavirus en pacientes graves ingresados en UCI.

Infections have become one of the main complications of patients with severe SARS-CoV-2 pneumonia admitted in ICU. Poor immune status, frequent development of organic failure requiring invasive supportive treatments, and prolonged ICU length of stay in saturated structural areas of patients are risk factors for infection development. The Working Group on Infectious Diseases and Sepsis GTEIS of the Spanish Society of Intensive Medicine and Coronary Units SEMICYUC emphasizes the importance of infection prevention measures related to health care, the detection and early treatment of major infections in the patient with SARS-CoV-2 infections. Bacterial co-infection, respiratory infections related to mechanical ventilation, catheter-related bacteremia, device-associated urinary tract infection and opportunistic infections are review in the document.

Improved survival among ICU-hospitalized patients with community-acquired pneumonia by unidentified organisms: a multicenter case-control study.

A retrospective analysis from prospectively collected data was conducted in intensive care units (ICUs) at 33 hospitals in Europe comparing the trend in ICU survival among adults with severe community-acquired pneumonia (CAP) due to unknown organisms from 2000 to 2015. The secondary objective was to establish whether changes in antibiotic policies were associated with different outcomes. ICU mortality decreased (p = 0.02) from 26.9 % in the first study period (2000-2002) to 15.7 % in the second period (2008-2015). Demographic data and clinical severity at admission were comparable between groups, except for age over 65 years and incidence of cardiomyopathy. Over time, patients received higher rates of combination therapy (94.3 vs. 77.2 %; p < 0.01) and early (<3 h) antibiotic delivery (72.9 vs. 50.3 %; p < 0.01); likewise, the 2008-2015 group was more likely to receive adequate antibiotic prescription [as defined by the Infectious Diseases Society of America/American Thoracic Society (IDSA/ATS) guidelines] than the 2000-2002 group (70.7 vs. 48.2 %; p < 0.01). Multivariate analysis showed an independent association between decreased ICU mortality and early (<3 h) antibiotic administration [odds ratio (OR) 3.48 [1.70-7.15], p < 0.01] or adequate antibiotic prescription according to guidelines (OR 2.22 [1.11-4.43], p = 0.02). In conclusion, our findings suggest that ICU mortality in severe CAP due to unidentified organisms has decreased in the last 15 years. Several changes in management and better compliance with guidelines over time were associated with increased survival.

Impact of a multifaceted educational intervention including serious games to improve the management of invasive candidiasis in critically ill patients.

OBJECTIVES: Infections caused by Candida species are common in critically ill patients and contribute to significant morbidity and mortality. The EPICO Project (Epico 1 and Epico 2.0 studies) recently used a Delphi approach to elaborate guidelines for the diagnosis and treatment of this condition in critically ill adult patients. We aimed to evaluate the impact of a multifaceted educational intervention based on the Epico 1 and Epico 2.0 recommendations. DESIGN: Specialists anonymously responded to two online surveys before and after a multifaceted educational intervention consisting of 60-min educational sessions, the distribution of slide kits and pocket guides with the recommendations, and an interactive virtual case presented at a teleconference and available for online consultation. SETTING: A total of 74 Spanish hospitals. PARTICIPANTS: Specialists of the Intensive Care Units in the participating hospitals. VARIABLES OF INTEREST: Specialist knowledge and reported practices evaluated using a survey. The McNemar test was used to compare the responses in the pre- and post-intervention surveys. RESULTS: A total of 255 and 248 specialists completed both surveys, in both periods, respectively. The pre-intervention surveys showed many specialists to be unaware of the best approach for managing invasive candidiasis. After both educational interventions, specialist knowledge and reported practices were found to be more in line with nearly all the recommendations of the Epico 1 and Epico 2.0 guidelines, except as regards de-escalation from echinocandins to fluconazole in Candida glabrata infections (p=0.055), and the duration of antifungal treatment in both candidemia and peritoneal candidiasis. CONCLUSIONS: This multifaceted educational intervention based on the Epico Project recommendations improved specialist knowledge of the management of invasive candidiasis in critically ill patients.

Community-acquired Legionella Pneumonia in the intensive care unit: Impact on survival of combined antibiotic therapy.

OBJECTIVES: To compare intensive care unit (ICU) mortality in patients with severe community-acquired pneumonia (SCAP) caused by Legionella pneumophila receiving combined therapy or monotherapy. METHODS: A prospective multicenter study was made, including all patients with sporadic, community-acquired Legionnaires' disease (LD) admitted to the ICU. Admission data and information on the course of the disease were recorded. Antibiotic prescriptions were left to the discretion of the attending physician and were not standardized. RESULTS: Twenty-five cases of SCAP due to L. pneumophila were included, and 7 patients (28%) out of 25 died after a median of 7 days of mechanical ventilation. Fifteen patients (60%) presented shock. Levofloxacin and clarithromycin were the antibiotics most commonly used in monotherapy, while the most frequent combination was rifampicin plus clarithromycin. Patients subjected to combination therapy presented a lower mortality rate versus patients subjected to monotherapy (odds ratio for death [OR] 0.15; 95%CI 0.02-1.04; p=0.08). In patients with shock, this association was stronger and proved statistically significant (OR for death 0.06; 95%CI 0.004-0.86; p=0.04). CONCLUSIONS: Combined antibiotic therapy decreases mortality in patients with SCAP and shock caused by L. pneumophila.

Impact of nosocomial polymicrobial bloodstream infections on the outcome in critically ill patients.

The aims of this study were to compare the clinical and microbiological characteristics from patients with polymicrobial bloodstream infections (BSI) to those from patients with monomicrobial BSI and to determine their influence on the prognosis. A prospective study was conducted on 371 nosocomial BSI in an intensive care unit (ICU). Seventy-five (20.2%) of them were polymicrobial. The mean APACHE II score at the onset of bacteremia in polymicrobial and monomicrobial BSI were 17.7 ± 6.6 and 18.9 ± 7.5, respectively (p=0.228). Severe sepsis and septic shock were present in 68.0% and 50.6% of polymicrobial BSI and in 73.9% and 55.1% of monomicrobial BSI, respectively (p=0.298 and p=0.494, respectively). The length of stay and the length of stay post-infection were significantly longer in patients with polymicrobial BSI. APACHE II score at the onset of BSI, high-risk microorganisms, and septic shock were predictors of related mortality, but polymicrobial BSI and inadequate empirical antimicrobial treatment were not. Our findings suggest that the clinical and microbiological characteristics of polymicrobial BSI are not different from monomicrobial BSI, and polymicrobial BSI do not have any influence on the related mortality. However, they occurred in patients with a longer length of stay in the hospital and were associated with longer stays in the hospital after the episode of BSI.

[Recommendations of the Infectious Diseases Work Group (GTEI) of the Spanish Society of Intensive and Critical Care Medicine and Coronary Units (SEMICYUC) and the Infections in Critically Ill Patients Study Group (GEIPC) of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) for the diagnosis and treatment of influenza A/H1N1 in seriously ill adults admitted to the Intensive Care Unit]. / Recomendaciones del Grupo de Trabajo Enfermedades Infecciosas (GTEI) de la Sociedad Española de Medicina Intensiva, Crítica y Unidades Coronarias (SEMICYUC) y el Grupo de Estudio de Infecciones en el Paciente Crítico (GEIPC) de la Sociedad Española de Enfermedades Infecciosas y Microbiología clínica (SEIMC) para el diagnóstico y tratamiento de la gripe A/H1N1 en pacientes adultos graves hospitalizados en las Unidades de Cuidados Intensivos.

The diagnosis of influenza A/H1N1 is mainly clinical, particularly during peak or seasonal flu outbreaks. A diagnostic test should be performed in all patients with fever and flu symptoms that require hospitalization. The respiratory sample (nasal or pharyngeal exudate or deeper sample in intubated patients) should be obtained as soon as possible, with the immediate start of empirical antiviral treatment. Molecular methods based on nucleic acid amplification techniques (RT-PCR) are the gold standard for the diagnosis of influenza A/H1N1. Immunochromatographic methods have low sensitivity; a negative result therefore does not rule out active infection. Classical culture is slow and has low sensitivity. Direct immunofluorescence offers a sensitivity of 90%, but requires a sample of high quality. Indirect methods for detecting antibodies are only of epidemiological interest. Patients with A/H1N1 flu may have relative leukopenia and elevated serum levels of LDH, CPK and CRP, but none of these variables are independently associated to the prognosis. However, plasma LDH> 1500 IU/L, and the presence of thrombocytopenia <150 x 10(9)/L, could define a patient population at risk of suffering serious complications. Antiviral administration (oseltamivir) should start early (<48 h from the onset of symptoms), with a dose of 75 mg every 12h, and with a duration of at least 7 days or until clinical improvement is observed. Early antiviral administration is associated to improved survival in critically ill patients. New antiviral drugs, especially those formulated for intravenous administration, may be the best choice in future epidemics. Patients with a high suspicion of influenza A/H1N1 infection must continue with antiviral treatment, regardless of the negative results of initial tests, unless an alternative diagnosis can be established or clinical criteria suggest a low probability of influenza. In patients with influenza A/H1N1 pneumonia, empirical antibiotic therapy should be provided due to the possibility of bacterial coinfection. A beta-lactam plus a macrolide should be administered as soon as possible. The microbiological findings and clinical or laboratory test variables may decide withdrawal or not of antibiotic treatment. Pneumococcal vaccination is recommended as a preventive measure in the population at risk of suffering severe complications. Although the use of moderate- or low-dose corticosteroids has been proposed for the treatment of influenza A/H1N1 pneumonia, the existing scientific evidence is not sufficient to recommend the use of corticosteroids in these patients. The treatment of acute respiratory distress syndrome in patients with influenza A/H1N1 must be based on the use of a protective ventilatory strategy (tidal volume <10 ml / kg and plateau pressure <35 mmHg) and positive end-expiratory pressure set to high patient lung mechanics, combined with the use of prone ventilation, muscle relaxation and recruitment maneuvers. Noninvasive mechanical ventilation cannot be considered a technique of choice in patients with acute respiratory distress syndrome, though it may be useful in experienced centers and in cases of respiratory failure associated with chronic obstructive pulmonary disease exacerbation or heart failure. Extracorporeal membrane oxygenation is a rescue technique in refractory acute respiratory distress syndrome due to influenza A/H1N1 infection. The scientific evidence is weak, however, and extracorporeal membrane oxygenation is not the technique of choice. Extracorporeal membrane oxygenation will be advisable if all other options have failed to improve oxygenation. The centralization of extracorporeal membrane oxygenation in referral hospitals is recommended. Clinical findings show 50-60% survival rates in patients treated with this technique. Cardiovascular complications of influenza A/H1N1 are common. Such problems may appear due to the deterioration of pre-existing cardiomyopathy, myocarditis, ischemic heart disease and right ventricular dysfunction. Early diagnosis and adequate monitoring allow the start of effective treatment, and in severe cases help decide the use of circulatory support systems. Influenza vaccination is recommended for all patients at risk. This indication in turn could be extended to all subjects over 6 months of age, unless contraindicated. Children should receive two doses (one per month). Immunocompromised patients and the population at risk should receive one dose and another dose annually. The frequency of adverse effects of the vaccine against A/H1N1 flu is similar to that of seasonal flu. Chemoprophylaxis must always be considered a supplement to vaccination, and is indicated in people at high risk of complications, as well in healthcare personnel who have been exposed.

Impact of Aspergillus spp. isolation in the first 24 hours of admission in critically ill patients with severe influenza virus pneumonia.

OBJECTIVE: To determine the incidence and impact of Aspergillus spp. isolation (AI) on ICU mortality in critically ill patients with severe influenza pneumonia during the first 24h of admission. DESIGN: Secondary analysis of an observational and prospective cohort study. SETTING: ICUs voluntary participating in the Spanish severe Influenza pneumonia registry, between June 2009 and June 2019. PATIENTS: Consecutive patients admitted to the ICU with diagnosis of severe influenza pneumonia, confirmed by real-time polymerase chain reaction. INTERVENTIONS: None. MAIN VARIABLES OF INTEREST: Incidence of AI in respiratory samples. Demographic variables, comorbidities, need for mechanical ventilation and the presence of shock according at admission. Acute Physiology and Chronic Health Evaluation II (APACHE II) scale calculated on ICU admission. RESULTS: 3702 patients were analyzed in this study. AI incidence was 1.13% (n=42). Hematological malignancies (OR 4.39, 95% CI 1.92-10.04); HIV (OR 3.83, 95% CI 1.08-13.63), and other immunosuppression situations (OR 4.87, 95% CI 1.99-11.87) were factors independently associated with the presence of Aspergillus spp. The automatic CHAID decision tree showed that hematologic disease with an incidence of 3.3% was the most closely AI related variable. Hematological disease (OR 2.62 95% CI 1.95-3.51), immunosuppression (OR 2.05 95% CI 1.46-2.88) and AI (OR 3.24, 95% CI 1.60-6.53) were variables independently associated with ICU mortality. CONCLUSIONS: Empirical antifungal treatment in our population may only be justified in immunocompromised patients. In moderate-high risk cases, active search for Aspergillus spp. should be implemented.

[Acute viral infections in immunocompetent patients]. / Infecciones virales graves en pacientes inmunocompetentes.

Viruses play a significant role in serious infections in adults and sometimes lead to the need for hospitalization and admission to intensive care units, especially in cases of severe respiratory distress or encephalopathy. Influenza and parainfluenza viruses, syncytial respiratory virus, herpes viruses and adenovirures are the most frequent causes of these severe infections. A review of the literature has been performed in order to update the epidemiology, pathogenesis and therapeutic approach of viral infections affecting immunocompetent patients. Furthermore, ventilator-associated pneumonia (VAP) is the most frequent nosocomial infection in intensive care units and has a high morbidity and mortality rate. It is mainly a bacterial disease, although the potential role of viruses as pathogens or copathogens in VAP is under discussion. Therefore, a brief review of the potential pathogenic role of viruses in VAP has also been performed.

[Role of viral infections in immunosuppressed patients]. / Papel de las infecciones víricas en pacientes inmunodeprimidos.

Being a solid organ and hematopoietic stem cell transplant recipient as well as receiving chemotherapy for a malignant hematological disease clearly predispose the subject to a variety of viral infections, both common and opportunistic diseases. The patient may have acquired these infections from the community as well as from the donor organ (donor-derived infections) and/or from reactivation of an endogenous latent virus. Herpes viruses and especially the cytomegalovirus and Epstein-Barr virus are among the most common of the opportunistic viral pathogens affecting these patients, in addition to respiratory viruses. Treatment consists in antiviral drug therapies combined with the reduction in the degree of the induced immunosuppression. A review of the literature has been performed in order to update the epidemiology, pathogenesis, clinical manifestations and therapeutic approach of the viral infections in these immunocompromised patients.

First influenza season after the 2009 pandemic influenza: report of the first 300 ICU admissions in Spain.

INTRODUCTION: During the 2009 influenza pandemic, several reports were published, nevertheless, data on the clinical profiles of critically ill patients with the new virus infection during this second outbreak are still lacking. MATERIAL METHODS: Prospective, observational, multi-center study conducted in 148 Spanish intensive care units (ICU) during epidemiological weeks 50-52 of 2010 and weeks 1 - 4 of 2011. RESULTS: Three hundred patients admitted to an intensive care unit (ICU) with confirmed An/H1N1 infection were analyzed. The median age was 49 years [IQR=38-58] and 62% were male. The mean APACHE II score was 16.9 ± 7.5 and the mean SOFA score was 6.3 ± 3.5 on admission. Comorbidities were present in 76% (n=228) of cases and 111 (37.4%) patients were reportedly obese and 59 (20%) were COPD. The main presentation was viral pneumonia with severe hypoxemia in 65.7% (n=197) of the patients whereas co-infection was identified in 54 (18%) patients. All patients received antiviral treatment and initiated empirically in 194 patients (65.3%), however only 53 patients (17.6%) received early antiviral treatment. Vaccination was only administered in 22 (7.3%) patients. Sixty-seven of 200 patients with ICU discharge died. Haematological disease, severity of illness, infiltrates in chest X-ray and need for mechanical ventilation were variables independently associated with ICU mortality. CONCLUSIONS: In patients admitted to the ICU in the post-pandemic seasonal influenza outbreak vaccination was poorly implemented and appear to have higher frequency of severe comorbidities, severity of illness, incidence of primary viral pneumonia and increased mortality when compared with those observed in the 2009 pandemic outbreak.

Cleavage and activation of LIM kinase 1 as a novel mechanism for calpain 2-mediated regulation of nuclear dynamics.

Calpain-2 (CAPN2) is a processing enzyme ubiquitously expressed in mammalian tissues whose pleiotropic functions depend on the role played by its cleaved-products. Nuclear interaction networks, crucial for a number of molecular processes, could be modified by CAPN2 activity. However, CAPN2 functions in cell nucleus are poorly understood. To unveil CAPN2 functions in this compartment, the result of CAPN2-mediated interactions in cell nuclei was studied in breast cancer cell (BCC) lines. CAPN2 abundance was found to be determinant for its nucleolar localization during interphase. Those CAPN2-dependent components of nucleolar proteome, including the actin-severing protein cofilin-1 (CFL1), were identified by proteomic approaches. CAPN2 binding, cleavage and activation of LIM Kinase-1 (LIMK1), followed by CFL1 phosphorylation was studied. Upon CAPN2-depletion, full-length LIMK1 levels increased and CFL1/LIMK1 binding was inhibited. In addition, LIMK1 accumulated at the cell periphery and perinucleolar region and, the mitosis-specific increase of CFL1 phosphorylation and localization was altered, leading to aberrant mitosis and cell multinucleation. These findings uncover a mechanism for the role of CAPN2 during mitosis, unveil the critical role of CAPN2 in the interactions among nuclear components and, identifying LIMK1 as a new CAPN2-target, provide a novel mechanism for LIMK1 activation. CFL1 is crucial for cytoskeleton remodeling and mitosis, but also for the maintenance of nuclear structure, the movement of chromosomes and the modulation of transcription frequently altered in cancer cells. Consequently, the role of CAPN2 in the nuclear compartment might be extended to other actin-associated biological and pathological processes.

Management of infectious complications associated with coronavirus infection in severe patients admitted to ICU. / Manejo de las complicaciones infecciosas asociadas con la infección por coronavirus en pacientes graves ingresados en UCI.

Infections have become one of the main complications of patients with severe SARS-CoV-2 pneumonia admitted in ICU. Poor immune status, frequent development of organic failure requiring invasive supportive treatments, and prolonged ICU length of stay in saturated structural areas of patients are risk factors for infection development. The Working Group on Infectious Diseases and Sepsis GTEIS of the Spanish Society of Intensive Medicine and Coronary Units SEMICYUC emphasizes the importance of infection prevention measures related to health care, the detection and early treatment of major infections in the patient with SARS-CoV-2 infections. Bacterial co-infection, respiratory infections related to mechanical ventilation, catheter-related bacteremia, device-associated urinary tract infection and opportunistic infections are review in the document.

Management of infectious complications associated with coronavirus infection in severe patients admitted to ICU.

Infections have become one of the main complications of patients with severe SARS-CoV-2 pneumonia admitted in ICU. Poor immune status, frequent development of organic failure requiring invasive supportive treatments, and prolonged ICU length of stay in saturated structural areas of patients are risk factors for infection development. The Working Group on Infectious Diseases and Sepsis GTEIS of the Spanish Society of Intensive Medicine and Coronary Units SEMICYUC emphasizes the importance of infection prevention measures related to health care, the detection and early treatment of major infections in the patient with SARS-CoV-2 infections. Bacterial co-infection, respiratory infections related to mechanical ventilation, catheter-related bacteremia, device-associated urinary tract infection and opportunistic infections are review in the document.

Antibiotic selection in the treatment of acute invasive infections by Pseudomonas aeruginosa: Guidelines by the Spanish Society of Chemotherapy.

Pseudomonas aeruginosa is characterized by a notable intrinsic resistance to antibiotics, mainly mediated by the expression of inducible chromosomic ß-lactamases and the production of constitutive or inducible efflux pumps. Apart from this intrinsic resistance, P. aeruginosa possess an extraordinary ability to develop resistance to nearly all available antimicrobials through selection of mutations. The progressive increase in resistance rates in P. aeruginosa has led to the emergence of strains which, based on their degree of resistance to common antibiotics, have been defined as multidrug resistant, extended-resistant and panresistant strains. These strains are increasingly disseminated worldwide, progressively complicating the treatment of P. aeruginosa infections. In this scenario, the objective of the present guidelines was to review and update published evidence for the treatment of patients with acute, invasive and severe infections caused by P. aeruginosa. To this end, mechanisms of intrinsic resistance, factors favoring development of resistance during antibiotic exposure, prevalence of resistance in Spain, classical and recently appeared new antibiotics active against P. aeruginosa, pharmacodynamic principles predicting efficacy, clinical experience with monotherapy and combination therapy, and principles for antibiotic treatment were reviewed to elaborate recommendations by the panel of experts for empirical and directed treatment of P. aeruginosa invasive infections.

Possible mechanisms involved in the vasorelaxant effect produced by clobenzorex in aortic segments of rats.

Clobenzorex is a metabolic precursor of amphetamine indicated for the treatment of obesity. Amphetamines have been involved with cardiovascular side effects such as hypertension and pulmonary arterial hypertension. The aim of the present study was to investigate whether the direct application of 10-9-10-5 M clobenzorex on isolated phenylephrine-precontracted rat aortic rings produces vascular effects, and if so, what mechanisms may be involved. Clobenzorex produced an immediate concentration-dependent vasorelaxant effect at the higher concentrations (10-7.5-10-5 M). The present outcome was not modified by 10-6 M atropine (an antagonist of muscarinic acetylcholine receptors), 3.1×10-7 M glibenclamide (an ATP-sensitive K+ channel blocker), 10-3 M 4-aminopyridine (4-AP; a voltage-activated K+ channel blocker), 10-5 M indomethacin (a prostaglandin synthesis inhibitor), 10-5 M clotrimazole (a cytochrome P450 inhibitor) or 10-5 M cycloheximide (a general protein synthesis inhibitor). Contrarily, the clobenzorex-induced vasorelaxation was significantly attenuated (P<0.05) by 10-5 M L-NAME (a direct inhibitor of nitric oxide synthase), 10-7 M ODQ (an inhibitor of nitric oxide-sensitive guanylyl cyclase), 10-6 M KT 5823 (an inhibitor of protein kinase G), 10-2 M TEA (a Ca2+-activated K+ channel blocker and non-specific voltage-activated K+ channel blocker) and 10-7 M apamin plus 10-7 M charybdotoxin (blockers of small- and large-conductance Ca2+-activated K+ channels, respectively), and was blocked by 8×10-2 M potassium (a high concentration) and removal of the vascular endothelium. These results suggest that the direct vasorelaxant effect by clobenzorex on phenylephrine-precontracted rat aortic rings involved stimulation of the NO/cGMP/PKG/Ca2+-activated K+ channel pathway.

Effects of prolonged ethanol exposure on the glial fibrillary acidic protein-containing intermediate filaments of astrocytes in primary culture: a quantitative immunofluorescence and immunogold electron microscopic study.

We investigated the effects of ethanol exposure on the shape of the cell and the morphology of intermediate filaments (IF) of cortical astrocytes in primary culture. The content and distribution of glial fibrillary acidic protein (GFAP), the major component of glial IF, was assessed using an anti-GFAP monoclonal antibody and fluorescence scanning densitometry together with quantitative pre- and post-embedding immunogold electron microscopy. The astrocytes were from 21-day-old fetuses obtained from both control and chronic alcoholic rats and were cultured for 28 days in the absence or presence of ethanol (25 mM). The main findings were: (a) ethanol-exposed astrocytes failed to develop processes or to acquire a filamentous IF distribution pattern; (b) these cells showed less GFAP than astrocytes without alcohol; (c) ethanol interfered with the reorganization of the anti-GFAP binding sites from clustered to random; and (d) astrocytes from alcohol-exposed fetuses cultured in the absence of ethanol also showed these alterations, suggesting initial damage to astrocyte precursor cells. Since the glial filaments play a crucial role in creating a scaffolding that guides neuronal migration, the effect of ethanol on astrocyte IF may possibly be correlated with the mechanisms underlying mental retardation and motor dysfunction which are characteristics of fetal alcohol syndrome.

Effect of cell density on endothelin release from endothelial cells and phosphoramidon dependent inhibition.

The modulation of endothelin (ET) release from endothelial cells was investigated as a function of cell density. The present study examined the release of ET from bovine pulmonary artery endothelial cells (BPAEC) and bovine aortic endothelial cells (BAEC) at various cell densities, as well as the effects of phosphoramidon, thiorphan and pepstatin on ET release at different densities. ET release from BPAEC and BAEC decreased as cell density increased. This cell density effect was not observed with prostacyclin release from either BPAEC or BAEC. Phosphoramidon (1 mM) inhibited ET release at every density examined for both BPAEC and BAEC. Thiorphan (1 mM) inhibited ET release from BPAEC weakly at low density and had no effect on ET release from BAEC. Pepstatin (1 mM) slightly inhibited ET release in BPAEC at the lowest density and had no effect at any other cell density for either cell type. These protease inhibitors had no effect on cell viability as determined by trypan blue exclusion and a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide conversion assay. This study supports the concept that ET release is modulated by endothelial cell density. In addition, these data demonstrate that phosphoramidon, which presumably inhibits the endothelin converting enzyme, can inhibit ET release over a range of cell densities without affecting cell viability.

The influence of inadequate empirical antimicrobial treatment on patients with bloodstream infections in an intensive care unit.

OBJECTIVE: To determine the occurrence of inadequate antimicrobial therapy among critically ill patients with bacteremia and the factors associated with it, to identify the microorganisms that received inadequate antimicrobial treatment, and to determine the relationship between inadequate treatment and patients outcome. METHODS: From June 1995 to January 1999 we collected data on all clinically significant ICU-bacteremias in our teaching hospital. Clinical and microbiological characteristics were recorded and the adequacy of empirical antimicrobial treatment in each case was determined. We defined inappropriate empirical antimicrobial treatment as applying to infection that was not being effectively treated at the time the causative microorganism and its antibiotic susceptibility were known. Multivariate analysis was used to determine the variables associated with inappropriate empirical antimicrobial treatment and to evaluate the influence of this on the related mortality to bacteremia, using the SPSS package (9.0). RESULTS: Among 166 intensive care unit patients with bacteremia, 39 (23.5%) received inadequate antimicrobial treatment. In this last group the mean age of patients was 64.1 +/- 13.2 years, and 64% were men. Bacteremia was hospital-acquired in 92% of these cases. Eleven percent developed septic shock and 37.7% severe sepsis, and ultimately fatal underlying disease was present in 28.2% of patients given inadequate empirical antimicrobial treatment. The main sources of bacteremias in this group were: a vascular catheter (15.3%), respiratory (7.6%) or unknown (53.8%). The microorganisms most frequently isolated in the group with inadequate empirical antimicrobial treatment were: coagulase-negative staphylococci (29.5%), Acinetobacter baumannii (27.3%), Enterococcus faecalis, Pseudomonas aeruginosa, Enterobacter cloacae, Proteus mirabilis, Escherichia coli, and Candida species (4.5% each). The frequency of coagulase-negative staphylococci in the cases with inappropriate treatment was higher than in the group with appropriate treatment (OR 2.62; 95% CI: 1.10-6.21; P = 0.015). The global mortality rate was 56% and the related mortality was 30% in the group with inadequate empirical antimicrobial treatment. The only factor associated with inappropriate empirical antibiotic treatment was the absence of abdominal or respiratory focus (P = 0.04; OR = 0.35; 95% CI: 0.12-0.97). Septic shock was related to attributable mortality (P = 0.03; OR = 3.19; 95% CI: 1.08-9.40), but not inappropriate empirical antibiotic treatment (P = 0.24; OR = 1.71; 95% CI: 0.66-4.78). CONCLUSION: Almost a quarter of critically ill patients with bloodstream infections were given inadequate empirical antibiotic treatment, but mortality was not higher in the group with inadequate treatment than in the group with adequate treatment. This fact was probably due to microbiological factors and clinical features, such as the type of microorganism most frequently isolated and the source of the bacteremia.

Na+ dependent glutamate transporters (EAAT1, EAAT2, and EAAT3) in primary astrocyte cultures: effect of oxidative stress.

The Na+ -dependent L-glutamate transporters EAAT1(GLAST), EAAT2 (GLT-1) and EAAT3 (EAAC1) are expressed in primary astrocyte cultures, showing that the EAAT3 transporter is not neuron-specific. The presence of these three transporters was evaluated by RT-PCR, immunoblotting, immunocytochemical techniques, and transport activity. When primary astrocyte cultures were incubated with L-buthionine-(S,R)-sulfoximine (BSO), a selective inhibitor of gamma-glutamylcysteine synthetase, the GSH concentration was significantly lower than in control cultures, but the expression and amount of protein of EAAT1, EAAT2 and EAAT3 and transport of L-glutamate was unchanged. Oxidative stress was created by adding H(2)O(2) or tert.-butyl hydroperoxide (t-bOOH) to the primary astrocyte cultures and cell damage was evaluated by measuring activity of lactate dehydrogenase. Under oxidative stress, GSH levels were significantly lower than in control astrocytes; but the expression and the amount of protein of the three transporters remained unchanged. However, L-glutamate uptake was significantly lower in astrocytes under oxidative conditions when compared to controls. L-Glutamate uptake was not changed in the presence of ascorbate, but was partially recovered in the presence of DTT and GSH ethyl ester. This report emphasizes that oxidative stress and not GSH depletion alters transporter activity without changing transporter expression.

Protective effect of N-acetylcysteine on ischaemia-induced myocardial damage in canine heart.

The glutathione redox pathway is an important antioxidant system in the myocardium. N-Acetylcysteine is a low molecular weight glutathione precursor that has been used clinically to replenish glutathione stores. The present study was aimed at evaluating the protective effect of N-acetylcysteine on myocardial damage resulting from permanent coronary occlusion (without reperfusion) in anaesthetized dogs. N-Acetylcysteine (150 mg kg-1 i.v.) administered 2 min before occlusion reduced infarct size in dogs subjected to 24 h ischemia. The infarct size as a percentage of the area at risk was 86.8 +/- 3.6% (n = 11) in control (saline-treated) dogs and 68.2 +/- 2.4% (n = 7; P less than 0.05 vs control) in N-acetylcysteine-treated animals. Haemodynamic variables (heart rate, mean arterial pressure and rate-pressure product) were similar in the control and the treated group. Regional myocardial blood flow was determined with radioactive microspheres in ischaemic and non-ischaemic zones before occlusion and 3 h post-occlusion. N-Acetylcysteine did not influence the regional distribution of myocardial blood flow. The myocardial content of reduced glutathione was significantly (P less than 0.05) decreased 3 h post-occlusion (0.53 +/- 0.19 mumol/g-1; n = 5) compared to either pre-occlusion values (0.94 +/- 0.03 mumol/g-1; n = 8) or values 3 h post-occlusion in sham-operated animals (0.93 +/- 0.15 mumol/g-1; n = 5). Depletion of myocardial glutathione 3 h post-occlusion was not observed in dogs treated with N-acetylcysteine (0.87 +/- 0.11 mumol/g-1; n = 5).(ABSTRACT TRUNCATED AT 250 WORDS)