Characteristics and determinants of outcome of hospital-acquired bloodstream infections in intensive care units: the EUROBACT International Cohort Study.

PURPOSE: The recent increase in drug-resistant micro-organisms complicates the management of hospital-acquired bloodstream infections (HA-BSIs). We investigated the epidemiology of HA-BSI and evaluated the impact of drug resistance on outcomes of critically ill patients, controlling for patient characteristics and infection management. METHODS: A prospective, multicentre non-representative cohort study was conducted in 162 intensive care units (ICUs) in 24 countries. RESULTS: We included 1,156 patients [mean ± standard deviation (SD) age, 59.5 ± 17.7 years; 65 % males; mean ± SD Simplified Acute Physiology Score (SAPS) II score, 50 ± 17] with HA-BSIs, of which 76 % were ICU-acquired. Median time to diagnosis was 14 [interquartile range (IQR), 7-26] days after hospital admission. Polymicrobial infections accounted for 12 % of cases. Among monomicrobial infections, 58.3 % were gram-negative, 32.8 % gram-positive, 7.8 % fungal and 1.2 % due to strict anaerobes. Overall, 629 (47.8 %) isolates were multidrug-resistant (MDR), including 270 (20.5 %) extensively resistant (XDR), and 5 (0.4 %) pan-drug-resistant (PDR). Micro-organism distribution and MDR occurrence varied significantly (p < 0.001) by country. The 28-day all-cause fatality rate was 36 %. In the multivariable model including micro-organism, patient and centre variables, independent predictors of 28-day mortality included MDR isolate [odds ratio (OR), 1.49; 95 % confidence interval (95 %CI), 1.07-2.06], uncontrolled infection source (OR, 5.86; 95 %CI, 2.5-13.9) and timing to adequate treatment (before day 6 since blood culture collection versus never, OR, 0.38; 95 %CI, 0.23-0.63; since day 6 versus never, OR, 0.20; 95 %CI, 0.08-0.47). CONCLUSIONS: MDR and XDR bacteria (especially gram-negative) are common in HA-BSIs in critically ill patients and are associated with increased 28-day mortality. Intensified efforts to prevent HA-BSIs and to optimize their management through adequate source control and antibiotic therapy are needed to improve outcomes.

Novel murine dendritic cell lines: a powerful auxiliary tool for dendritic cell research.

Research in vitro facilitates discovery, screening, and pilot experiments, often preceding research in vivo. Several technical difficulties render Dendritic Cell (DC) research particularly challenging, including the low frequency of DC in vivo, thorough isolation requirements, and the vulnerability of DC ex vivo. Critically, there is not as yet a widely accepted human or murine DC line and in vitro systems of DC research are limited. In this study, we report the generation of new murine DC lines, named MutuDC, originating from cultures of splenic CD8α conventional DC (cDC) tumors. By direct comparison to normal WT splenic cDC subsets, we describe the phenotypic and functional features of the MutuDC lines and show that they have retained all the major features of their natural counterpart in vivo, the splenic CD8α cDC. These features include expression of surface markers Clec9A, DEC205, and CD24, positive response to TLR3 and TLR9 but not TLR7 stimuli, secretion of cytokines, and chemokines upon activation, as well as cross-presentation capacity. In addition to the close resemblance to normal splenic CD8α cDC, a major advantage is the ease of derivation and maintenance of the MutuDC lines, using standard culture medium and conditions, importantly without adding supplementary growth factors or maturation-inducing stimuli to the medium. Furthermore, genetically modified MutuDC lines have been successfully obtained either by lentiviral transduction or by culture of DC tumors originating from genetically modified mice. In view of the current lack of stable and functional DC lines, these novel murine DC lines have the potential to serve as an important auxiliary tool for DC research.

Development of a T Cell Receptor Targeting an HLA-A*0201 Restricted Epitope from the Cancer-Testis Antigen SSX2 for Adoptive Immunotherapy of Cancer.

The clinical success of adoptive immunotherapy of cancer relies on the selection of target antigens that are highly expressed in tumor cells but absent in essential normal tissues. A group of genes that encode the cancer/testis or cancer germline antigens have been proposed as ideal targets for immunotherapy due to their high expression in multiple cancer types and their restricted expression in immunoprivileged normal tissues. In the present work we report the isolation and characterization of human T cell receptors (TCRs) with specificity for synovial sarcoma X breakpoint 2 (SSX2), a cancer/testis antigen expressed in melanoma, prostate cancer, lymphoma, multiple myeloma and pancreatic cancer, among other tumors. We isolated seven HLA-A2 restricted T cell receptors from natural T cell clones derived from tumor-infiltrated lymph nodes of two SSX2-seropositive melanoma patients, and selected four TCRs for cloning into retroviral vectors. Peripheral blood lymphocytes (PBL) transduced with three of four SSX2 TCRs showed SSX241-49 (KASEKIFYV) peptide specific reactivity, tumor cell recognition and tetramer binding. One of these, TCR-5, exhibited tetramer binding in both CD4 and CD8 cells and was selected for further studies. Antigen-specific and HLA-A*0201-restricted interferon-γ release, cell lysis and lymphocyte proliferation was observed following culture of TCR engineered human PBL with relevant tumor cell lines. Codon optimization was found to increase TCR-5 expression in transduced T cells, and this construct has been selected for development of clinical grade viral vector producing cells. The tumor-specific pattern of expression of SSX2, along with the potent and selective activity of TCR-5, makes this TCR an attractive candidate for potential TCR gene therapy to treat multiple cancer histologies.

Nouveautés dans la reconstruction cutanée: cultures de cellules et substituts dermiques et revue de la littérature.

La prise en charge de patients souffrant de brûlures profondes et étendues reste un défi important pour les chirurgiens reconstructeurs. Ceci est d'autant plus vrai que les grands progrès réalisés dans la réanimation assurent actuellement la survie de patients brûlés sur plus de 90% de leur surface corporelle. De ce fait la reconstruction moderne a dû innover et est devenue une chirurgie complexe nécessitant un plan stratégique impliquant des matériaux et des méthodes chirurgicales multiples adaptées à chaque situation clinique. Ce type de prise en charge nécessite aussi la collaboration étroite et coordonnée de plusieurs équipes hautement spécialisées. Le taux de survie ainsi que de la qualité de vie de ces patients sont alors nettement améliorés. De même nous observons clairement que le nombre de complications secondaires telles que les rétractions et les instabilités cicatricielles ont également diminué de façon significative.Mots-clés: brûlure, greffe, culture, substitut dermique, reconstruction.

Improved detection of microbial ureteral stent colonisation by sonication.

PURPOSE: The diagnosis of microbial ureteral stent colonisation (MUSC) is difficult, since routine diagnostic techniques do not accurately detect microorganisms embedded in biofilms. New methods may improve diagnostic yield and understanding the pathophysiology of MUSC. The aim of the present study was to evaluate the potential of sonication in the detection of MUSC and to identify risk factors for device colonisation. METHODS: Four hundred and eight polyurethane ureteral stents of 300 consecutive patients were prospectively evaluated. Conventional urine culture (CUC) was obtained prior to stent placement and device removal. Sonication was performed to dislodge adherent microorganisms. Data of patient sex and age, indwelling time and indication for stent placement were recorded. RESULTS: Sonicate-fluid culture detected MUSC in 36%. Ureteral stents inserted during urinary tract infection (UTI) were more frequently colonised (59%) compared to those placed in sterile urine (26%; P < 0.001). Female sex (P < 0.001) and continuous stenting (P < 0.005) were significant risk factors for MUSC; a similar trend was observed in patients older than 50 years (P = 0.16). MUSC and indwelling time were positively correlated (P < 0.005). MUSC was accompanied by positive CUC in 36%. Most commonly isolated microorganisms were Coagulase-negative staphylococci (18.3%), Enterococci (17.9%) and Enterobacteriaceae (16.9%). CONCLUSIONS: Sonication is a promising approach in the diagnosis of MUSC. Significant risk factors for MUSC are UTI at the time of stent insertion, female sex, continuous stenting and indwelling time. CUC is a poor predictor of MUSC. The clinical relevance of MUSC needs further evaluation to classify isolated microorganism properly as contaminants or pathogens.

Characterization of cardiac-resident progenitor cells expressing high aldehyde dehydrogenase activity.

High aldehyde dehydrogenase (ALDH) activity has been associated with stem and progenitor cells in various tissues. Human cord blood and bone marrow ALDH-bright (ALDH(br)) cells have displayed angiogenic activity in preclinical studies and have been shown to be safe in clinical trials in patients with ischemic cardiovascular disease. The presence of ALDH(br) cells in the heart has not been evaluated so far. We have characterized ALDH(br) cells isolated from mouse hearts. One percent of nonmyocytic cells from neonatal and adult hearts were ALDH(br). ALDH(very-br) cells were more frequent in neonatal hearts than adult. ALDH(br) cells were more frequent in atria than ventricles. Expression of ALDH1A1 isozyme transcripts was highest in ALDH(very-br) cells, intermediate in ALDH(br) cells, and lowest in ALDH(dim) cells. ALDH1A2 expression was highest in ALDH(very-br) cells, intermediate in ALDH(dim) cells, and lowest in ALDH(br) cells. ALDH1A3 and ALDH2 expression was detectable in ALDH(very-br) and ALDH(br) cells, unlike ALDH(dim) cells, albeit at lower levels compared with ALDH1A1 and ALDH1A2. Freshly isolated ALDH(br) cells were enriched for cells expressing stem cell antigen-1, CD34, CD90, CD44, and CD106. ALDH(br) cells, unlike ALDH(dim) cells, could be grown in culture for more than 40 passages. They expressed sarcomeric α -actinin and could be differentiated along multiple mesenchymal lineages. However, the proportion of ALDH(br) cells declined with cell passage. In conclusion, the cardiac-derived ALDH(br) population is enriched for progenitor cells that exhibit mesenchymal progenitor-like characteristics and can be expanded in culture. The regenerative potential of cardiac-derived ALDH(br) cells remains to be evaluated.

Prox1 interacts with Atoh1 and Gfi1, and regulates cellular differentiation in the inner ear sensory epithelia.

Inner ear hair cells and supporting cells arise from common precursors and, in mammals, do not show phenotypic conversion. Here, we studied the role of the homeodomain transcription factor Prox1 in the inner ear sensory epithelia. Adenoviral-mediated Prox1 transduction into hair cells in explant cultures led to strong repression of Atoh1 and Gfi1, two transcription factors critical for hair cell differentiation and survival. Luciferase assays showed that Prox1 can repress transcriptional activity of Gfi1 independently of Atoh1. Prox1 transduction into cochlear outer hair cells resulted in degeneration of these cells, consistent with the known phenotype of Gfi1-deficient mice. These results together with the widespread expression of endogenous Prox1 within the population of inner ear supporting cells point to the role for Prox1 in antagonizing the hair cell phenotype in these non-sensory cells. Further, in vivo analyses of hair cells from Gfi1-deficient mice suggest that the cyclin-dependent kinase inhibitor p57(Kip2) mediates the differentiation- and survival-promoting functions of Gfi1. These data reveal novel gene interactions and show that these interactions regulate cellular differentiation within the inner ear sensory epithelia. The data point to the tight regulation of phenotypic characteristics of hair cells and supporting cells.

Am I my brain or my genitals? A nature-culture controversy in the hermaphrodite debate from the mid-1960s to the late 1990s.

The groundbreaking and prophetic rhetoric of neuroscience has recently highlighted the fetal brain as the most promising organ for understanding why transsexuals feel "trapped in the wrong body", and for predicting whether children born with "ambiguous" genitalia will grow up to feel like a man or a woman.This article proposes a recent history of the cerebralization of intersexuality and of transsexuality as atypical neurodevelopmental conditions. It examines the ways in which the organizational theory of brain sex differentiation developed in the late 1950s in behavioral neuroendocrinology has gained increased prominence in and through controversies over best practice issues in the case management of intersex newborns, and the etiology of transsexuality.It focuses on the American context and on the leading warrior in this battle: Milton Diamond, now a most prominent figure in professional debates about the clinical management of intersexuality, and the intersex person's best friend. Persons with an intersexed or transsexual condition consider, not their gonads, but their brains, their core sense of self, as the primary determinant of sex. (Diamond and Beh 2005, 6-7, note 1)

African tick-bite fever: a new entity in the differential diagnosis of multiple eschars in travelers. Description of five cases imported from South Africa to Switzerland.

African tick-bite fever (ATBF) is a newly described spotted fever rickettsiosis that frequently presents with multiple eschars in travelers returning from sub-Saharan Africa and, to a lesser extent, from the West Indies. It is caused by the bite of an infected Amblyomma tick, whose hunting habits explain the typical presence of multiple inoculation skin lesions and the occurrence of clustered cases. The etiological agent of ATBF is Rickettsia africae, an emerging tick-borne pathogenic bacterium. We describe herein a cluster of five cases of ATBF occurring in Swiss travelers returning from South Africa. The co-incidental infections in these five patients and the presence of multiple inoculation eschars, two features pathognomonic of this rickettsial disease, suggested the diagnosis of ATBF. Indeed, the presence of at least one inoculation eschar is observed in 53-100% of cases and multiple eschars in 21-54%. Two patients presented regional lymphadenitis and one a mild local lymphangitis. Though a cutaneous rash is described in 15-46% of cases, no rash was observed in our series. ATBF was confirmed by serology. Thus, ATBF has recently emerged as one of the most important causes of flu-like illness in travelers returning from Southern Africa. The presence of one or multiple eschars of inoculation is an important clinical clue to the diagnosis. It can be confirmed by serology or by PCR of a biopsy of the eschar. Culture can also be done in reference laboratories. Dermatologists and primary care physicians should know this clinical entity, since an inexpensive and efficient treatment is available.