Expression pattern of sirtuins in innate immune cells and influence of Sirtuin 1/2 inhibition on innate immune responses to Toll-like receptor ligands and to infection

Purpose/Objective: The family of histone deacetylases comprises 18 members in mammals, among which seven sirtuins (SIRT1-7). Sirtuins are NADP-dependent enzymes that have been involved in the control of cell metabolism, proliferation and survival. The expression pattern of sirtuins and their influence on host response to microbial infection remain largely unknown. The aim of the study was to analyze the expression of SIRT1-7 and to address the effects of SIRT1/2 inhibition on innate immune responses in vitro and in vivo.. Materials and methods: in vitro: Bone marrow (BM), BM-derived macrophages (BMDMs) and dendritic cells (BMDCs) and RAW 264.7 and J774.1 macrophage cell lines were stimulated for 0, 2, 6 and 18 h with LPS, Pam3CSK4 and CpG ODN. SIRT1-7 mRNA was quantified by real time-PCR. TNF was measured by ELISA. In vivo: BALB/c mice were challenged with LPS (350 lg i.p.) with or without a SIRT1/2 inhibitor. Blood and organs were collected after 0, 1, 4, 8 and 24 h to quantify SIRT1-7 and TNF. Mortality was assessed daily. Results: Bone marrow, macrophages and DCs express, in order of abundance, SIRT2 > > SIRT1, SIRT3 and SIRT6 > SIRT4, SIRT5 and SIRT7. Microbial products decrease the expression of all sirtuins except SIRT6 in a time dependent manner in BMDMs (0_24 h). SIRT2 is the most expressed sirtuin also in the liver, kidney (together with SIRT3) and spleen. Upon LPS challenge, SIRT1, SIRT3, SIRT4 and SIRT7 mRNA levels decrease in the liver (from 4 h to 24 h), whereas SIRT1-7 mRNA levels decrease within 1 h in both kidney and spleen. Pharmacological inhibition of SIRT1/2 decreases TNF production by macrophages stimulated with LPS, Pam3CSK4 and CpG ODN (n = 6; P < 0.001). In agreement, prophylactic treatment with a SIRT1/2 inhibitor decreases TNF production (n = 8; P = 0.04) and increases survival (n = 13, P = 0.03) of mice challenged with LPS. Conclusions: Sirtuins are expressed in innate immune cells. Inhibition of SIRT1/2 activity decreases cytokine production by macrophages and protects from endotoxemia, suggesting that sirtuin inhibitors may represent novel adjunctive therapy for treating inflammatory disorders such as sepsis.

Determinants and trends in perinatal human immunodeficiency virus type 1 (HIV-1) transmission in the metropolitan area of Belo Horizonte, Brazil: 1998 - 2005

Significant decrease in human immunodeficiency virus type 1 (HIV-1) vertical transmission has been observed worldwide in centers where interventions such as antiretroviral therapy (ART), elective cesarean section, and avoidance of breastfeeding have been implemented. This prospective cohort study aimed to assess the determinants of and the temporal trends in HIV-1 vertical transmission in the metropolitan area of Belo Horizonte, Brazil from January 1998 to December 2005. The rate of HIV-1 vertical transmission decreased from 20% in 1998 to 3% in 2005. This decline was associated with increased use of more complex ART regimens during pregnancy. Multivariate analysis restricted to clinical variables demonstrated that non ART, neonatal respiratory distress/sepsis and breastfeeding were independently associated with HIV-1 vertical transmission. When laboratory parameters were included in the model, high maternal viral load and non maternal ART were associated with HIV-1 vertical transmission. The results from this study confirm the impact of ART in the reduction of HIV-1 vertical transmission and indicate the need for improvement in the care and monitoring of mother and infant pairs affected by HIV-1.

Revisiting steroid treatment for septic shock: molecular actions and clinical effects - a review

Corticosteroids are widely used to treat a diversity of pathological conditions including allergic, autoimmune and some infectious diseases. These drugs have complex mechanisms of action involving both genomic and non-genomic mechanisms and interfere with different signal transduction pathways in the cell. The use of corticosteroids to treat critically ill patients with acute respiratory distress syndrome and severe infections, such as sepsis and pneumonia, is still a matter of intense debate in the scientific and medical community with evidence both for and against its use in these patients. Here, we review the basic molecular mechanisms important for corticosteroid action as well as current evidence for their use, or not, in septic patients. We also present an analysis of the reasons why this is still such a controversial point in the literature.

Pronostic du coma après lésion cérébrale aiguë chez l'homme

Contexte: L'ensemble des phénomènes aigus suivant un arrêt cardio-respiratoire (ACR) est décrit sous le nom de maladie de post-réanimation (MPR) (post-resuscitation disease). Celle- ci est la conséquence du syndrome de reperfusion et est caractérisée par une réponse inflammatoire systémique intense, d'allure septique. La procalcitonine (PCT) est un marqueur aigu de la réponse inflammatoire systémique, qui a été beaucoup étudiée aux soins intensifs (SI) dans le contexte du sepsis, et constitue un outil diagnostic et pronostique important. Toutefois la PCT n'est pas un marqueur spécifique pour le sepsis mais peut également augmenter lors de réponse inflammatoire systémique d'origine non infectieuse. Objectifs: 1) Evaluer s'il existe une corrélation entre la valeur plasmatique de PCT et la MPR ; 2) examiner la relation entre le taux au pic de PCT et le pronostic des patients avec coma post-ACR ; 3) comparer la valeur pronostique de la PCT à celle d'un marqueur pronostic connu du coma post-anoxique tel que la neuron specific enolase (NSE). Méthodologie: Analyse d'une base de données prospective comprenant des patients admis aux SI du centre hospitalier universitaire vaudoise (CHUV) entre décembre 2009 et juillet 2011 en raison d'un ACR et traités par hypothermie thérapeutique (33 - 34 °C pendant 24h), selon notre protocole standard de prise en charge. La concentration plasmatique de PCT est mesurée à 24-72h après ACR, la valeur maximale (PCTmax) étant incluse dans l'analyse. La durée de l'arrêt circulatoire et le score de SOFA (Sequential Organ Failure Assessment) sont utilisés pour quantifier la sévérité de la MPR. Le pronostic est composé de la mortalité hospitalière, ainsi que la mortalité et la récupération neurologique à trois mois, mesurée avec le score de « Cerebral Performance Categories » (CPC), dichotomisé en bonne récupération (CPC 1 = pas de handicap ; CPC 2 = handicap modéré) et mauvaise récupération (CPC 3 = handicap sévère ; CPC 4 = état végétatif ; CPC 5 = décès). Résultats: 68 patients consécutifs (âge médian 65 ans, durée médiane totale de l'arrêt circulatoire [time to ROSC] 20.5 min) ont été étudiés. La PCTmax corrélait avec la durée de l'arrêt circulatoire (p = 0.001) ainsi qu'avec les scores de SOFA à l'admission et aux jours 1 et 2 (p<0.001 pour les trois associations). Une association significative a été observée entre la PCTmax et la survie hospitalière (médiane 3.9 [écart interquartile (EI) 1.0 - 16.8] chez les non-survivants vs. 1.4 [EI 0.6 - 6.2] ng/ml chez les survivants, p=0.032) et à trois mois (médiane 3.8 ([EI 1.0 - 15.6] vs. 1.4 [EI 0.5 - 6.0] ng/ml, p=0.034). La PCTmax était aussi plus basse chez les patients avec bonne récupération neurologique à trois mois (p=0.064). En comparaison avec la NSEmax, la PCTmax avait une valeur prédictive supérieure pour la sévérité de la maladie de post-réanimation et inférieure pour le pronostic. Conclusions: La valeur plasmatique maximale de PCT corrèle avec la sévérité de la MPR et est associé à la mortalité et à l'état neurologique à trois mois après coma post-anoxique. Ces données suggèrent que la PCT peut être un marqueur utile dans la prise en charge des patients comateux après ACR et hypothermie thérapeutique. Des études à plus large échelle sont en cours pour confirmer ces résultats.

Bacteremia due to extended-spectrum beta-lactamase-producing Escherichia coli in the CTX-M era: a new clinical challenge.

Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli, particularly those producing CTX-M types of ESBL, are emerging pathogens. Bacteremia caused by these organisms represents a clinical challenge, because the organisms are frequently resistant to the antimicrobials recommended for treatment of patients with suspected E. coli sepsis. METHODS:A cohort study was performed that included all episodes of bloodstream infection due to ESBL-producing E. coli during the period from January 2001 through March 2005. Data on predisposing factors, clinical presentation, and outcome were collected. ESBLs were characterized using isoelectric focusing, polymerase chain reaction, and sequencing. RESULTS: Forty-three episodes (8.8% of cases of bacteremia due to E. coli) were included; 70% of the isolates produced a CTX-M type of ESBL. The most frequent origins of infection were the urinary (46%) and biliary tracts (21%). Acquisition was nosocomial in 21 cases (49%), health care associated in 14 cases (32%), and strictly community acquired in 8 cases (19%). Thirty-eight percent and 25% of patients had obstructive diseases of the urinary and biliary tracts, respectively, and 38% had recently received antimicrobials. Nine patients (21%) died. Compared with beta-lactam/beta-lactamase-inhibitor and carbapenem-based regimens, empirical therapy with cephalosporins or fluoroquinolones was associated with a higher mortality rate (9% vs. 35%; P=.05) and needed to be changed more frequently (24% vs. 78%; P=.001). CONCLUSIONS: ESBL-producing E. coli is a significant cause of bloodstream infection in hospitalized and nonhospitalized patients in the context of the emergence of CTX-M enzymes. Empirical treatment of sepsis potentially caused by E. coli may need to be reconsidered in areas where such ESBL-producing isolates are present.

Candida albicans isolated from human fungaemia induces apoptosis in an experimental endocarditis model

Candida albicans is the most common fungal pathogen known to cause endovascular infections, such as vascular catheter sepsis, infections of vascular prostheses and infective endocarditis. A C. albicans isolate was used to determine the apoptotic potential of the fungus in a rat endocarditis model. This study confirms the ability of C. albicans to induce apoptosis in myocardial tissue.

Fistulizing Crohn's disease: Diagnosis and management.

Fistulizing Crohn's disease represents an evolving, yet unresolved, issue for multidisciplinary management. Perianal fistulas are the most frequent findings in fistulizing Crohn's disease. While enterocutaneous fistulas are rare, they are associated with considerable morbidity and mortality. Detailed evaluation of the fistula tract by advanced imaging techniques is required to determine the most suitable management options. The fundamentals of perianal fistula management are to evaluate the complexity of the fistula tract, and exclude proctitis and associated abscess. The main goals of the treatment are abscess drainage, which is mandatory, before initiating immunosuppressive medical therapy, resolution of fistula discharge, preservation of continence and, in the long term, avoidance of proctectomy with permanent stoma. The management of enterocutaneous fistulas comprises of sepsis control, skin care, nutritional optimization and, if needed, delayed surgery.

Rescue treatment with terlipressin in children with refractory septic shock: a clinical study

INTRODUCTION Refractory septic shock has dismal prognosis despite aggressive therapy. The purpose of the present study is to report the effects of terlipressin (TP) as a rescue treatment in children with catecholamine refractory hypotensive septic shock. METHODS We prospectively registered the children with severe septic shock and hypotension resistant to standard intensive care, including a high dose of catecholamines, who received compassionate therapy with TP in nine pediatric intensive care units in Spain, over a 12-month period. The TP dose was 0.02 mg/kg every four hours. RESULTS Sixteen children (age range, 1 month-13 years) were included. The cause of sepsis was meningococcal in eight cases, Staphylococcus aureus in two cases, and unknown in six cases. At inclusion the median (range) Pediatric Logistic Organ Dysfunction score was 23.5 (12-52) and the median (range) Pediatric Risk of Mortality score was 24.5 (16-43). All children had been treated with a combination of at least two catecholamines at high dose rates. TP treatment induced a rapid and sustained improvement in the mean arterial blood pressure that allowed reduction of the catecholamine infusion rate after one hour in 14 out of 16 patients. The mean (range) arterial blood pressure 30 minutes after TP administration increased from 50.5 (37-93) to 77 (42-100) mmHg (P < 0.05). The noradrenaline infusion rate 24 hours after TP treatment decreased from 2 (1-4) to 1 (0-2.5) microg/kg/min (P < 0.05). Seven patients survived to the sepsis episode. The causes of death were refractory shock in three cases, withdrawal of therapy in two cases, refractory arrhythmia in three cases, and multiorgan failure in one case. Four of the survivors had sequelae: major amputations (lower limbs and hands) in one case, minor amputations (finger) in two cases, and minor neurological deficit in one case. CONCLUSION TP is an effective vasopressor agent that could be an alternative or complementary therapy in children with refractory vasodilatory septic shock. The addition of TP to high doses of catecholamines, however, can induce excessive vasoconstriction. Additional studies are needed to define the safety profile and the clinical effectiveness of TP in children with septic shock.

Guidelines for specialized nutritional and metabolic support in the critically-ill patient. Update. Consensus SEMICYUC-SENPE: Obese patient

As a response to metabolic stress, obese critically-ill patients have the same risk of nutritional deficiency as the non-obese and can develop protein-energy malnutrition with accelerated loss of muscle mass. The primary aim of nutritional support in these patients should be to minimize loss of lean mass and accurately evaluate energy expenditure. However, routinely used formulae can overestimate calorie requirements if the patient's actual weight is used. Consequently, the use of adjusted or ideal weight is recommended with these formulae, although indirect calorimetry is the method of choice. Controversy surrounds the question of whether a strict nutritional support criterion, adjusted to the patient's requirements, should be applied or whether a certain degree of hyponutrition should be allowed. Current evidence suggested that hypocaloric nutrition can improve results, partly due to a lower rate of infectious complications and better control of hyperglycemia. Therefore, hypocaloric and hyperproteic nutrition, whether enteral or parenteral, should be standard practice in the nutritional support of critically-ill obese patients when not contraindicated. Widely accepted recommendations consist of no more than 60-70% of requirements or administration of 11-14 kcal/kg current body weight/day or 22-25 kcal/kg ideal weight/day, with 2-2.5 g/kg ideal weight/day of proteins. In a broad sense, hypocaloric-hyperprotein regimens can be considered specific to obese critically-ill patients, although the complications related to comorbidities in these patients may require other therapeutic possibilities to be considered, with specific nutrients for hyperglycemia, acute respiratory distress syndrome (ARDS) and sepsis. However, there are no prospective randomized trials with this type of nutrition in this specific population subgroup and the available data are drawn from the general population of critically-ill patients. Consequently, caution should be exercised when interpreting these data.

Guidelines for specialized nutritional and metabolic support in the critically-ill patient. Update. Consensus SEMICYUC-SENPE: Septic patient

Nutritional metabolic management, together with other treatment and support measures used, is one of the mainstays of the treatment of septic patients. Nutritional support should be started early, after initial life support measures, to avoid the consequences of malnutrition, to provide adequate nutritional intake and to prevent the development of secondary complications such as superinfection or multiorgan failure. As in other critically-ill patients, when the enteral route cannot be used to ensure calorie-protein requirements, the association of parenteral nutrition has been shown to be safe in this subgroup of patients. Studies evaluating the effect of specific pharmaconutrients in septic patients are scarce and are insufficient to allow recommendations to be made. To date, enteral diets with a mixture of substrates with distinct pharmaconutrient properties do not seem to be superior to standard diets in altering the course of sepsis, although equally there is no evidence that these diets are harmful. There is insufficient evidence to recommend the use of glutamine in septic patients receiving parenteral nutrition. However, given the good results and absence of glutamine-related adverse effects in the various studies performed in the general population of critically-ill patients, these patients could benefit from the use of this substance. Routine use of omega-3 fatty acids cannot be recommended until further evidence has been gathered, although the use of lipid emulsions with a high omega-6 fatty acid content should be avoided. Septic patients should receive an adequate supply of essential trace elements and vitamins. Further studies are required before the use of high-dose selenium can be recommended.

Perspectivas en el diseño y desarrollo de productos para nutrición enteral

Enteral nutrition is a technique that even though it was used in times immemorial, in the last 25 years has suffered a considerable development, from being considered a secondary therapeutic weapon destined only to feed the patient, to occupying an important status that goes beyond the single act of nourishing. The quantitative composition but overall the qualitative one, is object of an interesting argument in which a profile allowing the modulation of certain aspects of the organism response through the supplementation with different nutrients is searched. That includes from the keeping of the intestinal trophism and of the anti-bacteria intestinal barrier, so important to avoid the frightening multiple organ dysfunction, up to the lessening of the Systemic Response Inflammatory Syndrome (SRIS), going through the immuno-modulative feeding concepts, specific-feeding, pharmaco-nutrient or eco-nutrition. In this new dynamic not only certain nutrients such as glutamine, arginine, nucleotides, omega-3 fatty acids and many antioxidants have acquired importance, but also the manipulation of other molecules of a non- nutritional nature, such as hormones, cytokines and blockers. These aspects that imply passionate ways of investigation for the future are born from the better knowledge that is being acquired from such a severe pathophysiology processes such as sepsis and the organism response before fast and severe aggression; therefore, the modulation of that response through changes in the quantitative and qualitative formulas composition is being attempted.

High-mobility group box-1 protein determination in postmortem samples.

The aims of this study were to assess whether high-mobility group box-1 protein can be determined in biological fluids collected during autopsy and evaluate the diagnostic potential of high-mobility group box-1 protein in identifying sepsis-related deaths. High-mobility group box-1 protein was measured in serum collected during hospitalization as well as in undiluted and diluted postmortem serum and pericardial fluid collected during autopsy in a group of sepsis-related deaths and control cases with noninfectious causes of death. Inclusion criteria consisted of full biological sample availability and postmortem interval not exceeding 6h. The preliminary results indicate that high-mobility group box-1 protein levels markedly increase after death. Concentrations beyond the upper limit of the calibration curve were obtained in undiluted postmortem serum in septic and traumatic control cases. In pericardial fluid, concentrations beyond the upper limit of the calibration curve were found in all cases. These findings suggest that the diagnostic potential of high-mobility group box-1 protein in the postmortem setting is extremely limited due to molecule release into the bloodstream after death, rendering antemortem levels difficult or impossible to estimate even after sample dilution.

Granulocyte colony-stimulating factor in the treatment of high-risk febrile neutropenia: a multicenter randomized trial.

BACKGROUND Granulocyte colony-stimulating factors (G-CSFs) have been shown to help prevent febrile neutropenia in certain subgroups of cancer patients undergoing chemotherapy, but their role in treating febrile neutropenia is controversial. The purpose of our study was to evaluate-in a prospective multicenter randomized clinical trial-the efficacy of adding G-CSF to broad-spectrum antibiotic treatment of patients with solid tumors and high-risk febrile neutropenia. METHODS A total of 210 patients with solid tumors treated with conventional-dose chemotherapy who presented with fever and grade IV neutropenia were considered to be eligible for the trial. They met at least one of the following high-risk criteria: profound neutropenia (absolute neutrophil count <100/mm(3)), short latency from previous chemotherapy cycle (<10 days), sepsis or clinically documented infection at presentation, severe comorbidity, performance status of 3-4 (Eastern Cooperative Oncology Group scale), or prior inpatient status. Eligible patients were randomly assigned to receive the antibiotics ceftazidime and amikacin, with or without G-CSF (5 microg/kg per day). The primary study end point was the duration of hospitalization. All P values were two-sided. RESULTS Patients randomly assigned to receive G-CSF had a significantly shorter duration of grade IV neutropenia (median, 2 days versus 3 days; P = 0.0004), antibiotic therapy (median, 5 days versus 6 days; P = 0.013), and hospital stay (median, 5 days versus 7 days; P = 0.015) than patients in the control arm. The incidence of serious medical complications not present at the initial clinical evaluation was 10% in the G-CSF group and 17% in the control group (P = 0.12), including five deaths in each study arm. The median cost of hospital stay and the median overall cost per patient admission were reduced by 17% (P = 0.01) and by 11% (P = 0.07), respectively, in the G-CSF arm compared with the control arm. CONCLUSIONS Adding G-CSF to antibiotic therapy shortens the duration of neutropenia, reduces the duration of antibiotic therapy and hospitalization, and decreases hospital costs in patients with high-risk febrile neutropenia.

Community cluster of meningococcal disease by Neisseria meningitidis serogroup C in Andalusia, Spain, March to May 2011.

Between March and May of 2011, a cluster of three fatal cases of meningococcal sepsis occurred in Andalusia, Spain, in a municipality with a population of around 20,000 inhabitants. The cases were in their mid-teens to early thirties and were notified to the epidemiological surveillance system of Andalusia (Sistema de Vigilancia Epidemiológica de Andalucía, SVEA) during a 68-day period from March through May 2011. All three were infected with the same strain of Neisseria meningitidis serogroup C genosubtype VR1:5-1;VR2:10-8. None of the cases had been previously vaccinated against N. meningitidis serogroup C. Antibiotic post-exposure chemoprophylaxis was administered to close contacts of every diagnosed case. Once the cluster was confirmed, the local population was informed through the media about the control measures taken by the health authorities. The vaccination history against N. meningitidis serogroup C of the population under 25 years-old in the municipality was checked. Vaccination was offered to unimmunised individuals younger than 25 years of age and an additional dose of vaccine was offered to those who had been vaccinated between 2000 and 2006 with a vaccination schedule of three doses before the first year of age. No further cases occurred since the beginning of these actions.

Complicated intra-abdominal infections in a worldwide context: an observational prospective study (CIAOW Study).

Despite advances in diagnosis, surgery, and antimicrobial therapy, mortality rates associated with complicated intra-abdominal infections remain exceedingly high. The World Society of Emergency Surgery (WSES) has designed the CIAOW study in order to describe the clinical, microbiological, and management-related profiles of both community- and healthcare-acquired complicated intra-abdominal infections in a worldwide context. The CIAOW study (Complicated Intra-Abdominal infection Observational Worldwide Study) is a multicenter observational study currently underway in 57 medical institutions worldwide. The study includes patients undergoing surgery or interventional drainage to address complicated intra-abdominal infections. This preliminary report includes all data from almost the first two months of the six-month study period. Patients who met inclusion criteria with either community-acquired or healthcare-associated complicated intra-abdominal infections (IAIs) were included in the study. 702 patients with a mean age of 49.2 years (range 18-98) were enrolled in the study. 272 patients (38.7%) were women and 430 (62.3%) were men. Among these patients, 615 (87.6%) were affected by community-acquired IAIs while the remaining 87 (12.4%) suffered from healthcare-associated infections. Generalized peritonitis was observed in 304 patients (43.3%), whereas localized peritonitis or abscesses was registered in 398 (57.7%) patients.The overall mortality rate was 10.1% (71/702). The final results of the CIAOW Study will be published following the conclusion of the study period in March 2013.