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Background: Mycobacterium abscessus belongs to the largest group of mycobacteria, the rapid-growing saprophytic mycobacteria, and is one of the most difficult-to-treat opportunistic pathogen. Several features pertain to the high adaptability of M. abscessus to the host. These include the capacity to survive and persist within amoebae, to transition from a smooth to a rough morphotype that occurs during the course of the disease and to express of a wide array of virulence factors., Objectives: The main objective of this narrative review consists to report major assets of M. abscessus that contribute to the virulence of these rapid-growing saprophytic mycobacteria. Strikingly, many of these determinants, whether they are from a mycobacterial origin or acquired by horizontal gene transfer, are known virulence factors found in slow-growing and strict pathogens for humans and animals., Sources: In the light of recent published work in the field we attempted to highlight major features characterizing M. abscessus pathogenicity and to explain why this led to the emergence of this mycobacterial species in patients with cystic fibrosis., Content: M. abscessus genome plasticity, the smooth-to-rough transition, and the expression of a panel of enzymes associated with virulence in other bacteria are key players in M. abscessus virulence. In addition, the very large repertoire of lipid transporters, known as mycobacterial membrane protein large and small (MmpL and MmpS respectively), deeply influences the pathogenicity of M. abscessus, as exemplified here for some of them., Implications: All these traits largely contribute to make M. abscessus a unique mycobacterium regarding to its pathophysiological processes, ranging from the early colonization steps to the establishment of severe and chronic pulmonary diseases., (Copyright © 2023 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Background: Culture conditions sometimes make it difficult to detect non-tuberculous mycobacteria (NTM), particularly Mycobacterium abscessus, an emerging cystic fibrosis (CF) pathogen. The diagnosis of NTM positive cases not detected by classical culture methods might benefit from the development of a serological assay., Methods: As part of a diagnostic accuracy study, a total of 173 sera CF-patients, including 33 patients with M. abscessus positive cultures, and 31 non-CF healthy controls (HC) were evaluated. Four M. abscessus antigens were used separately, comprising two surface extracts (Interphase (INP) and a TLR2 positive extract (TLR2eF)) and two recombinant proteins (rMAB_2545c and rMAB_0555 also known as the phospholipase C (rPLC))., Results: TLR2eF and rPLC were the most efficient antigens to discriminate NTM-culture positive CF-patients from NTM-culture negative CF-patients. The best clinical values were obtained for the detection of M. abscessus-culture positive CF-patients; with sensitivities for the TLR2eF and rPLC of 81.2% (95% CI:65.7-92.3%) and 87.9% (95% CI:71.9-95.6%) respectively, and specificities of 88.9% (95% CI:85.3-94.8%) and 84.8% (95% CI:80.6-91.5%) respectively. When considering as positive all sera, giving a positive response in at least one of the two tests, and, as negative, all sera negative for both tests, we obtained a sensitivity of 93.9% and a specificity of 80.7% for the detection of M. abscessus-culture positive CF-patients., Conclusion: High antibody titers against TLR2eF and rPLC were obtained in M. abscessus-culture positive CF-patients, allowing us to consider these serological markers as potential tools in the detection of CF-patients infected with M. abscessus., Competing Interests: Declaration of Competing Interest All authors declare no conflicts of interest regarding the study., (Copyright © 2021 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

Background: Patients receiving a right ventricle to pulmonary artery conduit (PC) in infancy will require successive procedures or replacements, each with variable longevity. We sought to identify factors associated with time-related risk of a subsequent surgical replacement (PC3) or transcatheter pulmonary valve insertion (TPVI) after a second surgically placed PC (PC2)., Methods: From 2002 to 2016, 630 patients from 29 Congenital Heart Surgeons' Society member institutions survived to discharge after initial valved PC insertion (PC1) at age ≤ 2 years. Of those, 355 underwent surgical replacement (PC2) of that initial conduit. Competing risk methodology and multiphase parametric hazard analyses were used to identify factors associated with time-related risk of PC3 or TPVI., Results: Of 355 PC2 patients (median follow-up, 5.3 years), 65 underwent PC3 and 41 TPVI. Factors at PC2 associated with increased time-related risk of PC3 were smaller PC2 Z score (hazard ratio [HR] 1.6, P < .001), concomitant aortic valve intervention (HR 7.6, P = .009), aortic allograft (HR 2.2, P = .008), younger age (HR 1.4, P < .001), and larger Z score of PC1 (HR 1.2, P = .04). Factors at PC2 associated with increased time-related risk of TPVI were aortic allograft (HR: 3.3, P = .006), porcine unstented conduit (HR 4.7, P < .001), and older age (HR 2.3, P = .01)., Conclusions: Aortic allograft as PC2 was associated with increased time-related risk of both PC3 and TPVI. Surgeons may reduce risk of these subsequent procedures by not selecting an aortic homograft at PC2, and by oversizing the conduit when anatomically feasible., (Copyright © 2022 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: The stentless porcine aortic root prosthesis (SPAR) has been described as a suitable valve for right ventricular outflow tract reconstruction (RVOTR). Indiana University Methodist Hospital in Indianapolis, Indiana began using this valve for RVOTR in 1998. This study reports medium-term to late- term outcomes of the valve in the pulmonary position., Methods: A retrospective chart review was conducted of patients older than 18 years of age who underwent RVOTR with a SPAR between April 2000 and October 2019. Primary outcomes included survival and freedom from any valvular reintervention. Secondary outcomes included endocarditis and conduit dysfunction detected by routine echocardiography or cardiac magnetic resonance imaging., Results: A total of 135 patients underwent RVOTR with a SPAR at a median age of 32.4 years (range, 18 to 71 years). Of these patients, 129 had previous surgery. Indications included pulmonary insufficiency (90.4%), stenosis (34.8%), endocarditis (7.4%), and carcinoid (4.4%). Median follow-up was 2.97 years (interquartile range, 0.6 to 8.0 years). Overall survival was 93.3%, with 3 perioperative death and 6 late deaths. Endocarditis developed in 4 patients (2.9%), 2 of whom required reoperation. Progressive conduit degradation was evident at 10 years, with 22.2% and 7.7% having moderate stenosis and insufficiency, respectively. Eight (5.9%) reinterventions included 2 surgical replacements, 3 percutaneous replacements, and 3 balloon valvuloplasties at means of 8.5, 7.4, and 2.2 years, respectively. Overall freedom from reintervention at 1, 5, and 10 years was 99.1%, 94.7% and 90.7%, respectively., Conclusions: In this large, single-institution experience with a long follow-up period, use of the SPAR demonstrated excellent midterm to long-term durability, low rates of endocarditis, and high freedom from reintervention., (Copyright © 2021 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Introduction: Understanding how hospital staff members (HSMs), including healthcare workers, acquired severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the first wave can guide the control measures in the current second wave in Europe., Methods: From March 5 to May 10, 2020, the Raymond-Poincaré Hospital held a weekday consultation for HSMs for PCR testing. HSMs were requested to complete a questionnaire on their potential exposure to SARS-CoV-2., Results: Of 200 HSMs screened, 70 tested positive for SARS-CoV-2. Ninety-nine HSMs completed the questionnaire of whom 28 tested positive for SARS-CoV-2. In the multivariable analysis, age of ≥44 years (aOR = 5.2, 95% CI [1.4-22.5]) and not systematically using a facemask when caring for a patient (aOR = 13.9, 95% CI [1.8-293.0]) were significantly associated with SARS-CoV-2 infection. Working in a COVID-19-dedicated ward (aOR = 0.7, 95% CI [0.2-3.2]) was not significantly associated with infection. Community-related exposure in and outside the hospital, hospital meetings without facemasks (aOR = 21.3, 95% CI [4.5-143.9]) and private gatherings (aOR = 10, 95% CI [1.3-91.0]) were significantly associated with infection., Conclusions: Our results support the effectiveness of barrier precautions and highlight in-hospital infections not related to patient care and infections related to exposure in the community. Protecting HSMs against COVID-19 is crucial in fighting the second wave of the epidemic., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: Multiple conduits for right ventricular outflow tract reconstruction exist, although the ideal conduit that maximizes outcomes remains controversial. We evaluated long-term outcomes and compared conduits for right ventricular outflow tract reconstruction in children with truncus arteriosus., Methods: Records of patients who underwent truncus arteriosus repair at our institution between 1981 and 2018 were retrospectively reviewed. Primary outcomes included survival and freedom from catheter reintervention or reoperation. Secondary analyses evaluated the effect of comorbidity, operation era, conduit type, and conduit size., Results: One hundred patients met inclusion criteria. Median follow-up time was 15.6 years (interquartile range, 5.3-22.2). Actuarial survival at 30 days, 5 years, 10 years, and 15 years was 85%, 72%, 72%, and 68%, respectively. Early mortality was associated with concomitant interrupted aortic arch (hazard ratio, 5.4; 95% confidence interval, 1.7-17.4; P = .005). Median time to surgical reoperation was 4.6 years (interquartile range, 2.9-6.8; n = 58). Right ventricle to pulmonary artery continuity was established with an aortic homograft (n = 14), pulmonary homograft (n = 41), or bovine jugular vein conduit (n = 36) in most cases. Multivariate analysis revealed longer freedom from reoperation with the bovine jugular vein conduit compared with the aortic homograft (hazard ratio, 3.1; 95% confidence interval, 1.3-7.7; P = .02) with no difference compared with the pulmonary homograft. Larger conduit size was associated with longer freedom from reoperation (hazard ratio, 0.7; 95% confidence interval, 0.6-0.9; P < .001)., Conclusions: The bovine jugular vein conduit is a favorable conduit for right ventricular outflow tract reconstruction in patients with truncus arteriosus. Concomitant interrupted aortic arch is a risk factor for early mortality., (Copyright © 2020 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Cerebrospinal fluid (CSF) testing is a key component for the diagnosis of central nervous system (CNS) infections. Current meningitis and encephalitis management guidelines agree on the need for CSF molecular testing in combination with other direct and indirect biological testing, both in CSF and blood. Multiplex molecular tests have been developed to reduce turnaround times and facilitate the diagnostic approach., Objectives: We aim to discuss the role of multiplex molecular panels in the management of CNS infections., Sources: The MEDLINE database and the grey literature have been searched for relevant articles., Content: New molecular multiplex panels are being developed to simultaneously detect a large array of neuropathogens in CSF. Although one of these assays has been US Food and Drug Administration-approved, extensive analytical and clinical validation is still missing, and suboptimal performance related issues have been raised. Its use has been associated with decreased costs, reduced length of hospital stay and reduced antiviral therapy administration in retrospective, industry-sponsored studies. The pros and cons of this multiplex syndromic approach are discussed in this narrative review., Implications: Molecular multiplex CNS infection diagnosis panels have been developed and present several attractive features, including ease of use and low turnaround time. However, suboptimal analytical performances render these tests difficult to use without additional confirmatory tests. Such panels are not comprehensive nor adapted to all situations, depending on the epidemiological or clinical context. Overall, available data in the literature currently do not support the use of a multiplex PCR panel in clinical routine as a 'stand-alone' molecular assay. Except in restricted laboratory capacity settings where such easy-to-use multiplex panels offer the diagnostic means that would otherwise not be available, the stepwise testing approach remains a more rational option. Serological testing both in blood and CSF should not be neglected, but it represents essential complementary tools regarding some neuropathogens., (Copyright © 2020 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Partial anomalous pulmonary venous return is a rare congenital heart defect characterized by 1 or more but not all of the pulmonary veins draining somewhere other than the left atrium, thereby creating a left-to-right shunt. Over time, right-sided volume overload may develop with its subsequent complications. We present a case of isolated partial anomalous pulmonary venous return in an older patient who underwent a Warden procedure at age 77 years, with rapid improvement in right ventricular size and function., (Copyright © 2019 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

The aim of this study was to describe the endotracheal respiratory flora in a population of adults suffering from neuromuscular or neurological disorders requiring a long-term tracheostomy and to identify risk factors for colonization. We conducted a prospective and single-center observational study among patients with chronic tracheostomy admitted for planned respiratory assessment between February 2015 and December 2016. Data were collected from patient interview and medical charts with a standardized questionnaire. A tracheal aspiration was performed for each patient. Humidifiers were analysed for bacteriological contamination. Overall 77 tracheal aspirates (TA) were obtained from patients included. Pathogenic bacteria were found in 90% of cases (69/77) with a majority of Pseudomonas aeruginosa (32/77, 41%), Staphylococcus aureus (34/77, 44%) and Serratia marcesens. (22/79, 38%) Amoxicillin + Clavulanic-acid and Cefotaxime were adapted for respectively in only 28% and 35% of the subjects due to the natural resistance of organisms. No pathogenic bacteria were isolated from humidifier samples. Risk factors significantly associated with P. aeruginosa colonization were residence in a medical-care home (p = 0.01, OR = 3.8 [1.1; 15.1]) and the presence of a cuff (p = 0.003, OR = 4.4 [1.1; 20.6]). Significant quantities of pathogenic bacteria are frequently isolated from TA of tracheostomised patients in the absence of infection. The frequent resistance of these pathogens to Amoxicillin + Clavulanic-acid precludes the use of this antibiotic in the empiric treatment of pneumonia in this population., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

We performed a literature search in the Medline database, using the PubMed website. The incidence of presumably infectious encephalitis is estimated at 1.5-7 cases/100,000 inhabitants/year, excluding epidemics. Infectious encephalitis and immune-mediated encephalitis share similar clinical signs and symptoms. The latter accounts for a significant proportion of presumably infectious encephalitis cases without any established etiological diagnosis; as shown from a prospective cohort study where 21% of cases were due to an immune cause. Several infectious agents are frequently reported in all studies: Herpes simplex virus (HSV) is the most frequent pathogen in 65% of studies, followed by Varicella-zoster virus (VZV) in several studies. Enteroviruses are also reported; being the most frequent viruses in two studies, and the 2nd or 3rd viruses in five other studies. There are important regional differences, especially in case of vector-borne transmission: Asia and the Japanese encephalitis virus, Eastern and Northern Europe/Eastern Russia and the tick-borne encephalitis virus, Northern America and Flavivirus or Alphavirus. Bacteria can also be incriminated: Mycobacterium tuberculosis and Listeria monocytogenes are the most frequent, after HSV and VZV, in a French prospective study. The epidemiology of encephalitis is constantly evolving. Epidemiological data may indicate the emergence and/or dissemination of new causative agents. The dissemination and emergence of causative agents are fostered by environmental, social, and economical changes, but prevention programs (vaccination, vector controls) help reduce the incidence of other infectious diseases and associated encephalitis (e.g., measles)., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

A large number of cystic fibrosis pathogens such as bacteria of the Burkholderia cepacia complex, Pseudomonas aeruginosa, or Mycobacterium abscessus are associated with complex therapeutic problems due to their inherent resistance to antibiotics. No vaccine is currently available against those pathogens. Vaccines are therefore crucial to combat these multidrug-resistant bacteria in specific clinical situations including cystic fibrosis. Various strategies may be considered to develop these vaccines. Similar virulence factors are expressed during the infection with various pathogens; they could thus be used as antigen to assess cross-protection. Many clinical trials are currently being conducted to try and develop a prophylactic treatment for patients presenting with cystic fibrosis., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Background: Mycobacterium massiliense is closely related to Mycobacterium abscessus and is also a frequent cause of mycobacterial lung disease in patients with cystic fibrosis (CF). There has been no previous investigation of possible differences between M. massiliense and M. abscessus infections in the setting of CF., Methods: We studied a prospective cohort of 16 M. massiliense and 27 M. abscessus lung infection cases with CF, with a mean follow-up of 6 years., Results: M. massiliense cases were younger than M. abscessus cases (mean age: 12.8 vs 17.1 years; p=0.02) at the time of the first mycobacterial isolation and also had lower body mass index values (mean: 16.4 vs 19.3 kg/m(2), p=0.002). All M. massiliense cases, except one, had negative BMI Z-score values at the time of the first mycobacterial isolation (11/12 vs 16/23 M. abscessus cases, p=0.04). Clarithromycin-based combination therapies led to mycobacterial eradication in 100% of M. massiliense cases but only in 27% of M. abscessus cases (p=0.009)., Conclusion: Our data show a particular link between M. massiliense and malnutrition specifically in CF patients. Unlike M. abscessus, the bacteriological response of M. massiliense to combination antibiotic therapies containing clarithromycin was excellent. Distinguishing between M. massiliense and M. abscessus has major clinical implications for CF patients., (Copyright © 2014 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

The in vitro activity of cefoxitin and imipenem was compared for 43 strains of the Mycobacterium abscessus complex, mostly isolated from cystic fibrosis patients. The MICs of imipenem were lower than those of cefoxitin, although the number of imipenem-resistant strains was higher according to the CLSI breakpoints. Strain comparisons indicated that the MICs of cefoxitin were significantly higher for Mycobacterium bolletii than for M. abscessus. The MICs of both β-lactams were higher for the rough morphotype than for the smooth morphotype. The clinical impact of the in vitro difference between the activity of imipenem and that of cefoxitin remains to be determined., (© 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.)

The potential role of a patient's resident microbial flora in the risk of acquiring multiresistant bacteria (MRB) during hospitalization is unclear. We investigated this role by cross-sectional study of 103 patients at risk of acquisition of Staphylococcus aureus (SA), resistant (MRSA) or not (MSSA) to methicillin, recruited in four French hospitals. The flora was analysed by an exhaustive culture-based approach combined with molecular and/or mass-spectrometry-based identification, and SA strain typing. Forty-three of the 53 SA-negative patients at entry were followed for up to 52 weeks: 19 (44.2%) remained negative for SA and 24 (55.8%) became positive, including 19 (79%) who acquired an MSSA, four (17%) who acquired an MRSA and one who acquired both (4%). Fifty-one different species were identified among the 103 patients, of which two, Corynebacterium accolens and Staphylococcus haemolyticus (p = 0.02-0.01), were more prevalent in the absence of SA. However, the same number of patients carrying or not these two species acquired an MSSA/MRSA during follow-up, regardless of antibiotic treatment received. Clustering analysis showed that the microbial flora was highly specific to each patient, and not predictive for acquisition of MSSA/MRSA or not. Patient-specific microbial resident flora is not predictive of SA acquisition., (© 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.)

Background: Clinical observations suggest that Mycobacterium avium complex (MAC) and Mycobacterium abscessus complex (MABSC) may affect cystic fibrosis (CF) patients with different characteristics and risk factors, but this has never been demonstrated within a single prospective cohort., Methods: We studied 50 MABSC-positive and 23 MAC-positive patients from a French prevalence study of non-tuberculous mycobacteria (NTM) in CF. Risk factors specifically associated with MABSC and MAC were analyzed by nested case-control studies, with two NTM-negative controls matched by age, sex and center for each case., Results: MAC-positive patients were significantly older than MABSC-positive patients (mean [SD] age, 23.1 [10.2] vs 17.4 [8.3] years, p=0.013), and were also older at CF diagnosis (mean [SD] age, 12.9 [16.1] vs 3.1 [7.7] years, p=0.015); they tended to be less frequent of the ΔF508/ΔF508 genotype (33.3 vs 61.1%, p=0.17) and to use pancreatic extracts less frequently (82.4 vs 97.6%, p=0.07). Risk factors identified by multivariate analysis were: i) in the MAC case-control study, an older age at CF diagnosis (p=0.004); ii) in the MABSC case-control study, at least one course of intravenous antibiotics (p=0.01) and more frequent isolation of Aspergillus (p=0.03)., Conclusions: MAC affects adult patients with a mild form of CF, whereas MABSC affects younger patients with more severe CF and more frequent intravenous antimicrobial treatment., (Copyright © 2012 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

Background: Transforming growth factor-α (TGF-α) has been shown to augment mesenchymal stem cell-mediated cardioprotection during acute ischemia and reperfusion in isolated heart models. To determine whether this pretreatment strategy would be effective in vivo, we hypothesized that the intramyocardial injection of mesenchymal stem cells pretreated with TGF-α after coronary artery ligation would confer greater preservation of cardiac function, reduction in infarct size, and reduction myocardial inflammation., Methods: Sprague-Dawley rats underwent left anterior descending coronary artery ligation. Ischemic border zones were injected 30 minutes later with vehicle (n = 11), 1 million mesenchymal stem cells (n = 9), or mesenchymal stem cells pretreated with TGF-α (250 ng/mL for 24 hours; n = 10). Cardiac function was assessed by echocardiography at 7 and 28 days after ligation. Infarct size was measured using triphenyltetrazolium chloride. Ischemic border zone cytokine expression was measured 30 days after infarction., Results: Myocardial function after ligation was greatest in hearts injected with cells pretreated with TGF-α in association with reduced ventricular remodeling and infarct size compared with vehicle-injected hearts. Myocardial interleukin 1β, interleukin 6, and TNF-α concentrations were lower, and Bcl-2 expression was higher, in hearts injected with either cell type. Vascular endothelial growth factor and matrix metalloproteinase-2 expression were highest in hearts that received pretreated cells., Conclusions: Intramyocardial injection of mesenchymal stem cells pretreated with TGF-α further protects cardiac function and reduces infarct size compared with injection of untreated cells. Pretreating donor cells with TGF-α may be useful for enhancing cell-based therapies for myocardial ischemia., (Copyright © 2011 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

LKB1, a known tumor suppressor, is mutated in Peutz-Jeghers Syndrome (PJS). It is responsible for the enhanced cancer risk in patients with PJS. Dysregulation of LKB1-dependent signaling also occurs in various epithelial cancers. UVB alters the expression of LKB1, though its role in the pathogenesis of skin cancer is unknown. Here we describe upregulation of LKB1 expression in UVB-induced murine basal cell carcinoma (BCC) and in human skin tumor keratinocytes. AMP-kinase and acetyl Co-A carboxylase, the downstream LKB1 targets, are also enhanced in this neoplasm. In addition, p-Akt, a kinase which inactivates GSK3β by its phosphorylation, is enhanced in BCCs. Consistently, an accumulation of p-GSK3β and an increase in activated nuclear β-catenin are found. mTOR signaling, which is also inhibited by LKB1, remains upregulated in BCCs. However, a marked decrease in the expression of sestrins, which function as potent negative regulators of mTOR is observed. Metformin, a known chemical inducer of this pathway, was found effective in immortalized HaCaT keratinocytes, but failed to activate the LKB1-dependent signaling in human carcinoma A431 cells. Thus, our data show that the LKB1/AMPK axis fails to regulate mTOR pathway, and a complex regulatory mechanism exists for the persistent mTOR activation in murine BCCs., (Copyright © 2011 Elsevier Inc. All rights reserved.)

We report a microbiological process for the documentation of prosthetic joint infection (PJI). Intraoperative periprosthetic tissue samples from 92 consecutive patients undergoing revision surgery for PJI were submitted to mechanized beadmill processing: specimens were aseptically collected in polypropylene vials, filled with sterile water and glass beads and submitted to mechanized agitation with a beadmill. The documentation rate of PJI following culture on solid and liquid media was 83.7% and the contamination rate 8.7%. Final documentation was obtained after overnight culture for 51.9% of cases and with 7 days of broth culture for all documented cases., (© 2010 The Authors. Clinical Microbiology and Infection © 2010 European Society of Clinical Microbiology and Infectious Diseases.)

Atrial fibrillation (AF) is the most common chronic arrhythmia in the United States and is associated with high morbidity rates and significant healthcare costs. Although medical therapy for AF modestly reduces complications, cardiac surgery continues to have an important role in the treatment of AF and is constantly evolving. Cardiothoracic surgeons are uniquely positioned to offer effective operations to patients with lone AF, in addition to those undergoing concomitant elective cardiac surgery. This review discusses (1) the burden of AF, (2) classification and electrophysiology of AF, (3) surgical techniques and outcomes, and (4) future directions in surgical therapy., (Copyright © 2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

A study was performed to compare matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS), linked to a recently engineered microbial identification database, and two rapid identification (ID) automated systems, BD Phoenix (Becton Dickinson Diagnostic Systems, France) and VITEK-2 (bioMérieux, Marcy L'Etoile, France), for the ID of coagulase-negative staphylococci (CoNS). Two hundred and thirty-four clinical isolates of CoNS representing 20 species were analyzed. All CoNS isolates were characterized by sodA gene sequencing, allowing interpretation of the ID results obtained using the respective database of each apparatus. Overall correct ID results were obtained in 93.2%, 75.6% and 75.2% of the cases with the MALDI-TOF-MS, Phoenix and VITEK-2 systems, respectively. Mis-ID and absence of results occurred in 1.7% and 5.1% of the cases with MALDI-TOF-MS, in 23.1% and 1.3% with the Phoenix, and in 13.7% and 0.9% with the VITEK-2 systems, respectively. In addition, with the latter automate, 10.3% of the IDs were proposed with remote possibility. When excluding the CoNS species not included in the databases of at least one of the three systems, the final percentage of correct results, Mis-ID and absence of ID were 97.4%, 1.3% and 1.3% with MALDI-TOF-MS, 79%, 21% and 0% with the Phoenix, and 78.6%, 10.3% and 0.9% with the VITEK-2 system, respectively. The present study demonstrates the robustness and high sensitivity of our microbial identification database used with MALDI-TOF-MS technology. This approach represents a powerful tool for the fast ID of clinical CoNS isolates.

Progenitor cell therapy is a promising treatment for ischemic heart disease. Early clinical trials of autologous bone marrow-derived progenitor cell therapy for acute and chronic myocardial ischemia showed modest functional improvements after cell delivery; however, the duration of these benefits remains unclear. Ongoing investigations continue to enhance our understanding of the mechanisms by which progenitor and stem cells function and how their survival and cardioprotective abilities can be improved. This review discusses: (1) relevant progenitor and stem cells in myocardial regenerative therapy, (2) routes of cell delivery to ischemic myocardium, (3) clinical trials investigating bone marrow-derived progenitor cell therapy for myocardial ischemia, and (4) future directions of the field.

We describe the treatment of a 16-year-old girl with calcific aortic stenosis, porcelain aorta, and calcific mitral stenosis with insufficiency using a valved apicoaortic conduit and mitral valve prosthesis. Both valve replacements were porcine bioprostheses, and the apicoaortic conduit was implanted without the use of cardiopulmonary bypass. In cases in which the degree of aortic calcification pre-empts manipulation of the coronary ostia, an apicoaortic conduit may offer a viable solution to improve left ventricular outflow obstruction.

Mesenchymal stem cells (MSCs) hold great promise for improving myocardial recovery after ischemia. The cardiothoracic surgeon is uniquely positioned to be at the forefront of any clinical application of this therapy. As such, a basic understanding of stem cells and the cytokines that affect stem cell function will be an essential component of the surgeon's ever-expanding knowledge base. This review provides: (1) a general overview of stem cells and MSCs in particular, (2) critically analyzes several cytokines known to alter MSC function, and (3) discusses methods to manipulate cytokine-activated MSCs to improve MSC function for potential clinical application.

Study: A comparative study which compared PPD skin testing inserted according to the French Society of Pneumology's recommendations and interferon gamma release assay (IGRA) (QuantiFERON((R)) TB Gold In-tube, QF-TB-IT, Cellestis, Carnegie, Australia) was performed during a tuberculosis contact investigation in our hospital., Patients: Nineteen French health-care workers (HCWs) volunteered to participate. All of the HCW enrolled were BCG vaccinated and had a normal chest X-ray at entry., Results: Among the HCW, 68.4% were TST positive. By comparison, only 31.6% had a positive QF-TB-IT result. We took advantage of the negative tube and the corresponding plasma for antibody detection by ELISA. None were ELISA positive. Fourteen HCWs were followed up. None of the HCWs accepted a course of antiTB chemoprophylaxis. Despite the difficulty in establishing a trend in kinetics, we saw the complexity of interpretation of a dynamic T-cell response after contact with an index case., Conclusion: This initial and first French picture provides us with the observation that only 44% of TST-positive HCW were IGRA positive, and the IGRA test allowed the detection of LTBI in two TST negative HCWs.

Background: Mesenchymal stem cells (MSCs) hold great therapeutic potential for the repair and regeneration of ischemic tissue, possibly through the release of beneficial paracrine factors. Sex differences have been observed in the paracrine function of MSCs. Female stem cells produce lower proinflammatory cytokines and higher levels of growth factors compared with their male counterparts. Ablation of tumor necrosis factor receptor 1 (TNFR1) increases protective growth factor production by male, but not by female, MSCs. We therefore hypothesized the following: (1) that female MSCs would improve myocardial recovery compared with male MSCs after ischemia-reperfusion injury (I/R); and (2) that MSCs isolated from TNFR1 knock out male, but not female, mice, would improve postischemic myocardial recovery compared with their wild type (WT) counterparts., Methods: Male adult Sprague-Dawley rat hearts were subjected to I/R by Langendorff isolated heart preparation. The MSCs were harvested from adult mice and cultured under normal conditions. Immediately prior to ischemia, one million MSCs were infused into the coronary circulation. Cardiac functional parameters were recorded continuously., Results: Pretreatment with MSCs from either sex significantly increased postischemic myocardial recovery as evidenced by improved left ventricular developed pressure, contractility, and rate of relaxation. Infusion with female MSCs was associated with a greater degree of myocardial recovery after I/R compared with male MSCs. The TNFR1 deficiency increased the degree of myocardial recovery associated with male MSCs, but not with female MSCs. No additional cardioprotection was observed when TNFR1 was ablated in female MSCs., Conclusion: Sex differences influence the cardioprotective effects of both WT and TNFR1 ablated MSCs.

Objective: Patients with chronic neurological disorders and cognitive impairment after tick bites are difficult to manage despite standard antibiotic therapy for Lyme disease. We wanted to correctly assess the disorders., Methods: Thirty patients were hospitalized for a standardized evaluation of their disorders: clinical examination, biological and serological studies, cerebral MRI, CSF study, neurophysiological exams, and neuropsychological evaluation of cognitive functions., Results: Clinical and biological results were non informative. We observed significant CSF abnormalities (64%), MRI Flair pictures (41%), neurophysiological exams (47%), and cognitive evaluation (100%)., Conclusions: A large and standardized evaluation should be made for each patient to improve the management and probably the treatment of these complex chronic symptoms observed after tick bites.

The development of in vitro blood tests that measure the delayed hypersensitivity reaction developed after contact with Mycobacterium tuberculosis will change progressively the diagnosis of M. tuberculosis infection. These blood assays (Quantiferon TB Gold, Cellestis, Australia; T-SPOT.TB, Oxford Immunotec, United Kingdom) use specific, complex M. tuberculosis antigens (ESAT-6 and CFP-10), whereas the intra-dermal Mantoux test is done with tuberculin, a complex mixture of more than 200 antigens. ESAT-6 and CFP-10 are absent from all the BCG vaccine strains used throughout the world. Significant improvement in the specificity with equivalent or increased sensitivity of the in vitro tests compared to the Mantoux test will lead eventually to replacement of the latter.

Rapid and sensitive detection of Mycobacterium tuberculosis complex (MTB) directly on clinical respiratory specimens is essential for a correct management of patients suspected of tuberculosis. For this purpose PCR-based kits are available to detect MTB in respiratory specimen but most of them need at least 4 hours to be completed. New methods, based on TRC method (TRC: Transcription Reverse transcription Concerted--TRCRapid M. Tuberculosis--Tosoh Bioscience, Tokyo, Japon) and dedicated monitor have been developed. A new kit (TRC Rapid M. tuberculosis and Real-time monitor TRCRapid-160, Tosoh Corporation, Japan) enabling one step amplification and real-time detection of MTB 16S rRNA by a combination of intercalative dye oxazole yellow-linked DNA probe and isothermal RNA amplification directly on respiratory specimens has been tested in our laboratory. 319 respiratory specimens were tested in this preliminary study and results were compared to smear and culture. Fourteen had a positive culture for MTB. Among theses samples, smear was positive in 11 cases (78.6%) and TRC process was positive in 8 cases (57.1%). Overall sensitivity of TRC compared to smear positive samples is 73%. Theses first results demonstrated that a rapid identification of MTB was possible (less than 2 processing hours for 14 specimens and about 1 hour for 1 specimen) in most cases of smear positive samples using ready to use reagents for real time detection of MTB rRNA in clinical samples. New pretreatment and extraction reagents kits to increase the stability of the sputum RNA and the extraction efficiency are now tested in our laboratory.

A new scenario has been unraveled recently--the interaction between the human dendritic cell (DC) and Mycobacterium tuberculosis. Whether this encounter represents a defense mechanism by the invaded host, or a smoke screen, masking the presence of an invader is still unknown. The intracellular behavior of M. tuberculosis inside DCs differs compared to macrophages (Mphis), with a failure of replication. The intracellular compartment of the DC, disconnected from the exocytic and endocytic pathways, and characterized by the absence of endoplasmic reticulum and Golgi features, places M. tuberculosis in a hostile environment, where a ready source of nutrients is scarce. The differential behavior inside Mphis and DCs is linked to a different portal of entry. DCs harbor surface lectins receptors, like DC-specific intercellular adhesion molecule-3 grabbing nonintegrin (DC-SIGN/CD209), a binding site which is absent on Mphis. This receptor interacts exclusively with M. tuberculosis. The ligand is the mannose-capped lipoarabinomanan (LAM), absent from atypical mycobacteria. M. smegmatis, M. chelonae and M. fortuitum, which possess LAM capped with phosphoinositides residues, do not bind to DC-SIGN, demonstrating a role for DC-SIGN as a 'pattern-recognition receptor' with the ability to differentiate between pathogenic and non-pathogenic mycobacteria. Interactions of M. tuberculosis with DC-SIGN have antiinflammatory effects. Whether this property is of benefit to the invader remains to be discovered.

Pulmonary disease due to Mycobacterium avium complex (MAC) without evidence of dissemination is uncommon in HIV-infected patients. Five cases were observed over a 2-year period. All patients had AIDS and the median CD4 cell count at the time of presentation was 90 x 10(6)/L. Radiographic patterns included unilobar alveolar infiltrates or diffuse alveolar densities. All patients had a favorable clinical response to antimycobacterial chemotherapy with a median follow-up period of 10 months. MAC should be considered in HIV-infected patients with positive respiratory samples for acid-fast bacilli and pulmonary infiltrates. Patients with such findings in whom presumptive therapy for tuberculosis has failed should receive broad-spectrum antimycobacterial chemotherapy until final identification is available.

Within the Leptospiraceae family, the genus Leptospira is divided into the pathogenic L. interrogans sensu lato and the saprophytic L. biflexa sensu lato. Based on DNA-DNA hybridization, L. interrogans sensu lato has been shown to contain 7 different genomic species. Each genomic species contains numerous serovars. Pulsed-field genetic studies performed during this work demonstrated a great heterogeneity of serovars, within genomic species, based on restriction length polymorphism analysis. In contrast, an identified serovar, despite the time and region of isolation, has been shown to be highly stable in its genomic structure. The most likely reasons for this finding include the long generation time of these bacteria and the lack of acquisition of heterologous DNA. New identification techniques, based on gene amplification, have been used for Leptospira strains. These techniques represent the first available to facilitate the study of the epidemiology of Leptospira.

Teicoplanin, a glycopeptide antibiotic, is active against Staphylococci, with the exception of some strains of coagulase negative Staphylococci (SCN). Determination of the in vitro activity of teicoplanin by standard disk methodology is not sufficient, and has to be confirmed by the determination of the minimal inhibitory concentration (MIC) for all strains presenting an inhibition zone diameter below 17 mm. We have studied during four months, the susceptibility of SCN to teicoplanin isolated from different units of the hospital, and in particular from the haematology unit (HU). 186 strains were isolated, 35 p. cent from HU and 65 p. cent from the other units of the hospital. All strains belonged to 11 species: 136 S. epidermidis, 14 S. haemolyticus, 8 S. lugdunensis, 5 S. warneri, 4 S. saprophyticus, 3 S. sciuri, 3 hominis, 2 S. chromogens, 2 xylosus, 2 S. cohnii and 1 S. schleiferi. Twenty five strains out of 186 (13.4%) presented a MIC of 8 or 16 mg/l (MIC verified by the agar dilution method): 7 S. haemolyticus, 16 S. epidermidis, 1 S. warneri et 1 S. capitis. During this study SCN resistant to teicoplanin were never isolated. Twelve out of 25 came from the HU, which correspond to 18 p. cent of the isolated strains in this unit. This result was not significantly different, compared to that of the other units.

The acute otitis media is a frequent infantile disease and, in 80% of cases, a bacterial strain can be isolated from the otorrhoea. Haemophilus influenzae and Streptococcus pneumoniae are the two major species isolated from auricular exudate, and represent two thirds of all isolated strains, with the others comprising Staphylococcus aureus, Branhamella catarrhalis, Pseudomonas aeruginosa, Enterobacteriaceae and corynebacteria. The treatment of this disease is based principally on beta-lactams (aminopenicillins, cephalosporins) administered by the oral route. Cefuroxime is a cephalosporin which is absorbed via the digestive tract in the form of cefuroxim-axetil. The activity of this compound was studied against 210 strains isolated from otorrhoea, collected from children who presented an acute otitis media during the first half of 1989. These strains were: 112 strains of H. influenzae, of which 23 produced a beta-lactamase; 21 strains of Streptococcus pneumoniae; 3 strains of Streptococcus pyogenes; 10 strains of Branhamella catarrhalis of which 9 produced a beta-lactamase; 18 strains of S. aureus; 14 strains of Enterobacteriaceae, and 32 strains of corynebacteria. The minimal inhibitory concentration (MIC) of cefuroxime-axetil was measured by dilution in agar. The MICs of cefuroxime against H. influenzae were low and similar (MIC 50 = 1 mg/l; MIC 90 = 1 mg/l) regardless of whether the strain secreted a beta-lactamase. Overall, 90% and 98% of the 210 strains tested here were inhibited by 1 and 4 mg/l of cefuroxime respectively. These results show that the antibacterial spectrum of cefuroxime-axetil appears to be ideally suited to the bacterial strains isolated from acute otitis media.

The antibacterial activity of cefapirin was tested against 210 strains isolated from the auricular exudate of childrens' acute otitis media. For 112 strains of Haemophilus studied (20% secreted a beta-lactamase), the MIC 50 and 90 of cefapirin were 2 and 4 mg/l respectively. Ten strains of Branhamella catarrhalis were tested (9 secreted a beta-lactamase) and the MIC ranged from 0.25 to 4 mg/l. Against Streptococcus pneumoniae, cefapirin has an extremely high activity with MIC 50 and 90 less than 0.06 mg/l. Of the strains of Staphylococcus aureus sensitive to meticillin, one had a MIC less than 0.06 mg/l, and 11 had a MIC = 0.25 mg/l. For 14 strains of Enterobacteriaceae studied, we obtained a MIC 50 of 8 mg/l and a MIC 90 of 32 mg/l. The results show that cefapirin is an antibiotic particularly suitable for the treatment of acute otitis media.