Optimising translational oncology in clinical practice: Strategies to accelerate progress in drug development.

Despite intense efforts, the socioeconomic burden of cancer remains unacceptably high and treatment advances for many common cancers have been limited, suggesting a need for a new approach to drug development. One issue central to this lack of progress is the heterogeneity and genetic complexity of many tumours. This results in considerable variability in therapeutic response and requires knowledge of the molecular profile of the tumour to guide appropriate treatment selection for individual patients. While recent advances in the molecular characterisation of different cancer types have the potential to transform cancer treatment through precision medicine, such an approach presents a major economic challenge for drug development, since novel targeted agents may only be suitable for a small cohort of patients. Identifying the patients who would benefit from individual therapies and recruiting sufficient numbers of patients with particular cancer subtypes into clinical trials is challenging, and will require collaborative efforts from research groups and industry in order to accelerate progress. A number of molecular screening platforms have already been initiated across Europe, and it is hoped that these networks, along with future collaborations, will benefit not only patients but also society through cost reductions as a result of more efficient use of resources. This review discusses how current developments in translational oncology may be applied in clinical practice in the future, assesses current programmes for the molecular characterisation of cancer and describes possible collaborative approaches designed to maximise the benefits of translational science for patients with cancer.

Treatment of an Aedes aegypti colony with the Cry11Aa toxin for 54 generations results in the development of resistance

To study the potential for the emergence of resistance in Aedes aegypti populations, a wild colony was subjected to selective pressure with Cry11Aa, one of four endotoxins that compose the Bacillus thuringiensis serovar israelensis toxin. This bacterium is the base component of the most important biopesticide used in the control of mosquitoes worldwide. After 54 generations of selection, significant resistance levels were observed. At the beginning of the selection experiment, the half lethal concentration was 26.3 ng/mL and had risen to 345.6 ng/mL by generation 54. The highest rate of resistance, 13.1, was detected in the 54th generation. Because digestive proteases play a key role in the processing and activation of B. thuringiensis toxin, we analysed the involvement of insect gut proteases in resistance to the Cry11Aa B. thuringiensis serovar israelensis toxin. The protease activity from larval gut extracts from the Cry11Aa resistant population was lower than that of the B. thuringiensisserovar israelensis susceptible colony. We suggest that differences in protoxin proteolysis could contribute to the resistance of this Ae. aegypti colony.

A male with unilateral microphthalmia reveals a role for TMX3 in eye development.

Anophthalmia and microphthalmia are important birth defects, but their pathogenesis remains incompletely understood. We studied a patient with severe unilateral microphthalmia who had a 2.7 Mb deletion at chromosome 18q22.1 that was inherited from his mother. In-situ hybridization showed that one of the deleted genes, TMX3, was expressed in the retinal neuroepithelium and lens epithelium in the developing murine eye. We re-sequenced TMX3 in 162 patients with anophthalmia or microphthalmia, and found two missense substitutions in unrelated patients: c.116G>A, predicting p.Arg39Gln, in a male with unilateral microphthalmia and retinal coloboma, and c.322G>A, predicting p.Asp108Asn, in a female with unilateral microphthalmia and severe micrognathia. We used two antisense morpholinos targeted against the zebrafish TMX3 orthologue, zgc:110025, to examine the effects of reduced gene expression in eye development. We noted that the morphant larvae resulting from both morpholinos had significantly smaller eye sizes and reduced labeling with islet-1 antibody directed against retinal ganglion cells at 2 days post fertilization. Co-injection of human wild type TMX3 mRNA rescued the small eye phenotype obtained with both morpholinos, whereas co-injection of human TMX3(p.Arg39Gln) mutant mRNA, analogous to the mutation in the patient with microphthalmia and coloboma, did not rescue the small eye phenotype. Our results show that haploinsufficiency for TMX3 results in a small eye phenotype and represents a novel genetic cause of microphthalmia and coloboma. Future experiments to determine if other thioredoxins are important in eye morphogenesis and to clarify the mechanism of function of TMX3 in eye development are warranted.

Respiratory infection in congenital cardiac disease. Hospitalizations in young children in Spain during 2004 and 2005: the CIVIC Epidemiologic Study.

OBJECTIVES To evaluate the rate of hospitalization for acute respiratory tract infection in children less than 24 months with haemodynamically significant congenital cardiac disease, and to describe associated risk factors, preventive measures, aetiology, and clinical course. MATERIALS AND METHODS We followed 760 subjects from October 2004 through April 2005 in an epidemiological, multicentric, observational, follow-up, prospective study involving 53 Spanish hospitals. RESULTS Of our cohort, 79 patients (10.4%, 95% CI: 8.2%-12.6%) required a total of 105 admissions to hospital related to respiratory infections. The incidence rate was 21.4 new admissions per 1000 patients-months. Significant associated risk factors for hospitalization included, with odds ratios and 95% confidence intervals shown in parentheses: 22q11 deletion (8.2, 2.5-26.3), weight below the 10th centile (5.2, 1.6-17.4), previous respiratory disease (4.5, 2.3-8.6), incomplete immunoprophylaxis against respiratory syncytial virus (2.2, 1.2-3.9), trisomy 21 (2.1, 1.1-4.2), cardiopulmonary bypass (2.0, 1.1-3.4), and siblings aged less than 11 years old (1.7, 1.1-2.9). Bronchiolitis (51.4%), upper respiratory tract infections (25.7%), and pneumonia (20%) were the main diagnoses. An infectious agent was found in 37 cases (35.2%): respiratory syncytial virus in 25, Streptococcus pneumoniae in 5, and Haemophilus influenzae in 4. The odds ratio for hospitalization due to infection by the respiratory syncytial virus increases by 3.05 (95% CI: 2.14 to 4.35) in patients with incomplete prophylaxis. The median length of hospitalization was 7 days. In 18 patients (17.1%), the clinical course of respiratory infection was complicated and 2 died. CONCLUSIONS Hospital admissions for respiratory infection in young children with haemodynamically significant congenital cardiac disease are mainly associated with non-cardiac conditions, which may be genetic, malnutrition, or respiratory, and to cardiopulmonary bypass. Respiratory syncytial virus was the most commonly identified infectious agent. Incomplete immunoprophylaxis against the virus increased the risk of hospitalization.

Time-based distribution of Staphylococcus saprophyticus pulsed field gel-electrophoresis clusters in community-acquired urinary tract infections

The epidemiology of urinary tract infections (UTI) by Staphylococcus saprophyticus has not been fully characterised and strain typing methods have not been validated for this agent. To evaluate whether epidemiological relationships exist between clusters of pulsed field gel-electrophoresis (PFGE) genotypes of S. saprophyticus from community-acquired UTI, a cross-sectional surveillance study was conducted in the city of Rio de Janeiro, Brazil. In total, 32 (16%) female patients attending two walk-in clinics were culture-positive for S. saprophyticus. Five PFGE clusters were defined and evaluated against epidemiological data. The PFGE clusters were grouped in time, suggesting the existence of community point sources of S. saprophyticus. From these point sources, S. saprophyticus strains may spread among individuals.

Meta-analysis of studies analyzing the role of human papillomavirus in the development of bladder carcinoma

PURPOSE We aimed to ascertain the degree of association between bladder cancer and human papillomavirus (HPV) infection. MATERIALS AND METHODS We performed a meta-analysis of observational studies with cases and controls with publication dates up to January 2011. The PubMed electronic database was searched by using the key words "bladder cancer and virus." Twenty-one articles were selected that met the required methodological criteria. We implemented an internal quality control system to verify the selected search method. We analyzed the pooled effect of all the studies and also analyzed the techniques used as follows: 1) studies with DNA-based techniques, among which we found studies with polymerase chain reaction (PCR)-based techniques and 2) studies with non-PCR-based techniques, and studies with non-DNA-based techniques. RESULTS Taking into account the 21 studies that were included in the meta-analysis, we obtained a heterogeneity chi-squared value of Q(exp)=26.45 (p=0.383). The pooled odds ratio (OR) was 2.13 (95% confidence interval [CI], 1.54 to 2.95), which points to a significant effect between HPV and bladder cancer. Twenty studies assessed the presence of DNA. The overall effect showed a significant relationship between virus presence and bladder cancer, with a pooled OR of 2.19 (95% CI, 1.40 to 3.43). Of the other six studies, four examined the virus's capsid antigen and two detected antibodies in serum by Western blot. The estimated pooled OR in this group was 2.11 (95% CI, 1.27 to 3.51), which confirmed the relationship between the presence of virus and cancer. CONCLUSIONS The pooled OR value showed a moderate relationship between viral infection and bladder tumors.

Metabolomic insights into the intricate gut microbial-host interaction in the development of obesity and type 2 diabetes.

Gut microbiota has recently been proposed as a crucial environmental factor in the development of metabolic diseases such as obesity and type 2 diabetes, mainly due to its contribution in the modulation of several processes including host energy metabolism, gut epithelial permeability, gut peptide hormone secretion, and host inflammatory state. Since the symbiotic interaction between the gut microbiota and the host is essentially reflected in specific metabolic signatures, much expectation is placed on the application of metabolomic approaches to unveil the key mechanisms linking the gut microbiota composition and activity with disease development. The present review aims to summarize the gut microbial-host co-metabolites identified so far by targeted and untargeted metabolomic studies in humans, in association with impaired glucose homeostasis and/or obesity. An alteration of the co-metabolism of bile acids, branched fatty acids, choline, vitamins (i.e., niacin), purines, and phenolic compounds has been associated so far with the obese or diabese phenotype, in respect to healthy controls. Furthermore, anti-diabetic treatments such as metformin and sulfonylurea have been observed to modulate the gut microbiota or at least their metabolic profiles, thereby potentially affecting insulin resistance through indirect mechanisms still unknown. Despite the scarcity of the metabolomic studies currently available on the microbial-host crosstalk, the data-driven results largely confirmed findings independently obtained from in vitro and animal model studies, putting forward the mechanisms underlying the implication of a dysfunctional gut microbiota in the development of metabolic disorders.

The role of Toll-like Receptor (TLR) 9 in the development of a T-helper (Th)1/Th2 response in the murine model of infection with " Leishmania major "

1.1 SUMMARY The role of the non-specific innate immune system is as important as the elaboration of the adaptive immune system in the initiation of an immune response to pathogens. The role of the Toll-like receptors (TLRs) in the innate immune response to virus and bacterial pathogens is widely recognised, however, little is known about the role of TLRs in host defence against eukaryotic pathogens. Immunologic investigations on the marine model of infection with Leishmania major (L. major) have correlated the outcome of the disease with expansion of different subsets of CD4+ cells, designated Th1 and Th2. The resistance of C57BL/6, CBA and C3H/He mice is linked with an IL-12 driven Th1 response. In BALB/c mice the susceptibility correlates with an IL-4 driven Th2 response. The initial event promoting the development of a Th1 or Th2 response still remains elusive. Recently, the contribution of the TLR signalling pathway in the innate and acquired immune response to infection with the intracellular protozoan parasite L. major has been demonstrated. Thus, the purpose of this study is to determine whether TLRs may play a role in influencing the outcome of the infection by directing the development of a Th1 or a Th2 response during infection with L, major parasites, in resistant C57BL/6 and susceptible BALB/c mice, respectively. We demonstrated that MyD88, the major TLR adaptor molecule is necessary for C57BL/6 to develop a resistant Th1 response following L. major infection. Our data show the essential role of MyD88 in the establishment of a protective Th1 response. We subsequently aimed to determine which TLRs may be involved in the protective response. Since TLR2 and TLR4 have shown to have a potential role for Leishmania recognition, we analysed the course of infection in TLR2 and TLR4 deficient mice on a C57BL/6 resistant background following L. major infection. Our results clearly demonstrate that TLR2 or TLR4 aze dispensable to control the outcome of the disease as the TLR2 and TLR4 knockout mice developed a protective Th1 response. With the aim of determining a potential TLR candidate important in the initiation of the Thl response, we assessed the mRNA expression of different TLRs (TLR1 to TLR9) using quantitative real-time RT-PCR at different time points during the first week of infection. The results clearly showed an upregulation of TLR7 and TLR9 mRNA expression during the early phase of infection in resistant C57BL/6 mice but not in susceptible BALB/c mice. To provide in vivo evidence for the role for, these TLRs in the outcome of cutaneous leishmaniasis, studies using TLR7 and TLR9 deficient mice on a resistant C57BL/6 background were performed. The TLR7 deficient mice developed a resistance phenotype that was comparable with C57BL/6 wild type mice. Thus, the presence of TLR7 is not indispensable for the development of a Th1 response and resistance to infection. On the contrary, TLR9 deficient mice on the C57BL/6 resistant background showed high variability in the outcome of the disease. Although some mice behave as resistant C57BL/6 mice, half of them developed high lesion following infection and showed a decrease in IFN-γ production and an increase in IL-4 as compared to wild type mice. These results suggest that TLR9 may be involved in the control of infection. To test the hypothesis that regulatory T cells (Treg) are playing a role in the high variability in the disease outcome in TLR9 deficient mice, depletion of CD4+CD25+ T cells with a specific antibody three days before infection with L. major were performed Interestingly, these treated mice developed large lesions, low IL-4 and decreased IFN-γ producion when compared to untreated mice. A better understanding of the mechanism by which Treg cells influence the outcome of the disease in TLR9 deficient mice following L. major infection is currently under investigation. Altogether, this study demonstrates the importance of TLR9 in the induction of a protective T'h1 response, a process that is involved in the resolution of the lesion induced by L. major infection. 1.2 RÉSUMÉ Le rôle de la réponse immunitaire innée a longtemps été négligé quant à l'impact qu'elle pourrait avoir dans l'initiation d'une réponse immune adaptative efficace dirigée contre un pathogène. Si l'importance des récepteurs Toll-like (TLR) du système inné dans la reconnaissance des virus et bactéries a été démontrée, son rôle dans la défense contre les pathogènes eucaryotes reste encore très élusif. Récemment, il a été montré que les voies de signalisation provenant de l'activation des TLRs pouvaient initier la réponse immunitaire innée et adaptative après une infection avec le parasite protozoaire Leishmania major (L. major). Dans un modèle marin d'infection avec L. major alors que la plupart des souches de souris telles que C57BL/6 sont résistantes à l'infection et développent une réponse immunitaire de type T helper 1 (Th1) induite par IL-12, peu de souches dont les BALB/c sont sensibles et développent une réponse Th2 induite par IL-4. La différentiation Th1/Th2 est un événement qui prend place de manière définitive lors de la première semaine après infection. Les événements précoces promouvant le développement d'une réponse Th1 ou Th2 n'étant pas connus, l'objectif de ce travail a été de démontrer un rôle des TLRs dans l'initiation d'une réponse immune innée et adaptative suite à l'infection par L. major. Nous avons démontré que MyD88, une molécule importante dans le processus de signalisation des TLRs, est nécessaire pour que les souris résistantes C57BL/6 développent une réponse Th1 protectrice. L'importance du rôle de TLR2 et TLR4 dans la reconnaissance du parasite Leishmania ayant été démontrée, nous avons privilégié l'analyse de la réponse immunitaire suite à une infection in vivo de souris déficiente en TLR2 ou TLR4 sur un fond génétique résistant. Les résultats obtenus montrent que la présence de ces récepteurs n'est pas indispensable pour le contrôle de l'infection et la polarisation d'une réponse Th1 caractéristique de la résistance à L. major. Cependant d'autres TLRs peuvent aussi activer la voie de signalisation MyD88 dépendante. L'expression de l'ARNm des différents TLRs dans les ganglions drainant de souris sensibles et résistantes pendant la première semaine d'infection a été déterminée par PCR quantitative en temps réel. Les résultats obtenus montrent que l'ARNm de TLR7 et TLR9 était régulé positivement suite à l'infection par L. major chez les souris résistantes C57BL/6 alors qu'aucune modulation n'était détectable chez les souris sensibles BALB/c. Le rôle des récepteurs TLR7 et TLR9 a donc été évalué par l'infection par L. major des souris déficientes en TLR7 et TLR9 sur fond génétique C57BL/6. Nos résultats ont clairement démontré que les souris déficientes en TLR7 montrent une réponse immunitaire identique à celle des souris résistantes C57BL/6, signifiant que TLR7 n'est pas indispensable au développement d'une Th1 ainsi qu'au contrôle de la parasitémie. Paz contre, les souris déficientes en TLR9 sur un fond génétique résistant ont montré une grande variabilité dans la réponse à l'infection. En effet, la moitié des souris deviennent sensibles à l'infection, ceci étant associé à une diminution dans la production d'IFN-γ et à une augmentation de la production d'IL-4. Ces résultats suggèrent que TLR9 est impliqué dans le contrôle de la lésion et de la réponse immunitaire suite à l'infection avec L. major. Cependant les résultats avec les souris déficientes en TLR9 montrant une grande hétérogénéité et une balance Th1/Th2 instable, nous avons émis l'hypothèse que les cellules T régulatrices pouvaient être impliquées dans ce phénomène. Nous avons effectivement constaté qu'après déplétion des cellules CD4+CD25+, les souris déficientes en TLR9 développent des lésions aussi grandes que les souris BALB/c après infection par L. major. Cependant le nombre de parasites reste le même que chez les souris C57BL/6. De plus la production d'IL-4 ainsi que celle d'IFN-γ reste extrêment bas. Les mécanismes régulateurs impliqués dans ce processus sont en cours d'analyse. Ce travail met en évidence l'importance du TLR9 dans le développement d'une réponse Th1 lors d'une infection avec L. major, un processus nécessaire pour la résistance à l'infection. 1.3 RESUME POUR UN LARGE PUBLIC La leishmaniose est une maladie parasitaire répandue dans le monde entier et touchant plus de 88 pays. L'incidence mondiale de la leishmaniose cutanée et de 1 à 1,5 million de nouveaux cas par année. Plus de 12 millions de personnes sont affectées par la maladie et 350 millions de personnes sont une population à risque. Un modèle marin d'infection avec Leishmania major (L. major) a été établi qui reproduit plusieurs tableaux cliniques observés dans le cas de la leishmaniose cutanée chez l'homme. L'analyse de la réponse immunitaire dans les souris infectées par L. major a permis de distinguer deux groupes : les souris de la plupart des souches telles que C57BL/6 sont résistantes à l'infection et développent une réponse immunitaire de type T helper 1 (Th1), alors que quelques souches dont les BALB/c sont sensibles et développent une réponse de type Th2. La réponse immune adaptative dans le modèle d'infection avec L. major à été largement étudiée. Cependant, les événements précoces déterminants pour le développement d'une réponse Th1 ou Th2 restent encore très flous. Récemment, plusieurs publications ont montré que les récepteurs Toll-like (TLR) peuvent contribuer à l'initiation de la réponse immunitaire lors d'une infection avec le parasite intracellulaire L. major. Dans ce travail de thèse, nous avons étudié le rôle de MyD88, une molécule importante dans le processus de signalisation des TLRs, dans la réponse immune suite à une infection avec L. major. En l'absence de MyD88, les souris normalement résistantes à l'infection avec L. major deviennent sensibles et développent des lésions importantes. Ces souris ne sont plus capables de développer une réponse Thl, normalement caractéristique de leur phénotype résistant. Nous avons ensuite tenté de comprendre quels TLRs, plus précisément, pouvait être impliqué dans ce processus. Malgré quelques évidences démontrant que TLR2 et TLR4 pouvaient avoir un rôle important dans l'initiation d'une réponse immunitaire adaptative à Leishmania, nous avons montré que, in vivo après infection avec L. major, la déficience d'un de ces récepteurs n'était pas suffisante à faire basculer la réponse immunitaire. Les souris C57BL/6 déficient en TLR2 ou TLR4 peuvent parfaitement contrôler l'évolution de la maladie. De plus, ces souris, malgré l'absence de TLR2 ou TLR4, sont capables de monter une parfaite réponse Thl. Etant donné que TLR2 et TLR4 n'étaient pas essentiels pour la résistance à la maladie, nous avons analysé les TLRs, parmi les 12 décrits qui pouvaient être indispensables au développement d'une réponse de type Th1 associée à la résistance à l'infection par Leishmania. Nos expériences ont montré que l'expression de l'ARN messager (ARNm) de TLR7 et TLR9 était modulée suite à l'infection par L. major chez la souris résistante C57BL/6 alors qu'aucune modulation n'était visible chez les souris sensible BALB/c. Pensant que ces TLRs pourraient jouer un rôle dans la réponse immunitaire au parasite, nous avons étudié l'évolution de l'infection dans les souris déficientes en TLR7 et TLR9. Nos résultats ont clairement démontré que TLR7 n'était pas indispensable à la résistance au parasite alors que l'absence de TLR9 avait des conséquences radicales sur le contrôle de la lésion et de la réponse immunitaire suite à l'infection avec L. major. Ce travail révèle ainsi l'importance du TLR9 dans le développement d'une réponse Th1 lors d'une infection avec L. major, un processus nécessaire pour la résistance à l'infection. Il est a noté que nos résultats sont en accord avec le fait que les motifs CpG, qui sont des immunostimulateurs interagissant avec le TLR9, ont une activité adjuvante importante dans la préparation de vaccins contre la leishmaniose. Une meilleure compréhension des mécanismes immunologiques impliquant le TLR9 dans la reconnaissance du parasite est alors indispensable pour le développement de vaccins thérapeutiques efficaces.

Sox genes in C. elegans: sox-2 role in postembryonic development

Report for the scientific sojourn carried out at the Columbia University, United States, from 2010 to 2012. Expression of SoxB genes correlates with the commitment of cells to a neural fate; however, the relevance of SoxB proteins in early vertebrate neurogenesis has been difficult to prove genetically due to embryonic lethality and presumed redundant functions. The nematode C. Elegants has only 5 sox genes: sox-2 and sox-3 form the SoxB group while sem-2, sox-4 and egl-13 belong to other Sox groups. Our results show that sox-2 and sem-2 are the sox genes expressed earliest and in a broader manner during embryogenesis, being expressed in several neuronal progenitors. sox-3, sox-4 and egl-13 are expressed in few cells during late embryogenesis, when most neurons are already born. Both sox-2 and sem-2 null mutants are early larval lethal but do not show neuronal specification defects during embryonic development as indicated by quantification of a panneuronal reporter. Potential redundancy or compensatory mechanisms between different sox genes have been ruled out, strongly suggesting that sox genes are not required for specification of embryonically-derived neurons. However, at the first larval stage there are still several blast cells that will give rise to different postembryonic lineages, which generate several neurons amongst other cell types. nterestingly, sox-2 is expressed in many of these progenitor cells. Using mosaic analysis we have so far identified neurons derived from two different postembryonic lineages which fail to be generated in C. elegans sox-2 mutants. These results support the idea that postembryonic progenitor competence is compromised in the absence of sox-2.

Identity formation in social networks websites: facebook and the interaction between young individuals in the cases of Slovenia and Catalonia

This paper lays down some theoretical framework for further research to be made on the subject of how identity of young Slovenian and Catalan users is forming within the social networking website Facebook. The author pursues his interest based on observation of how communicationand thus interaction between users is changing and how this is reflected in everyday practices. In so doing he tries to identify the connections between the individual, society and technology, asthese are more and more interwoven, and we cannot think one without the other in thecontemporary globalised world.

The role of Bmi1 in CNS development and in retinal degeneration

SUMMARY : The present work addresses several aspects of cell cycle regulation, cell fate specification and cell death in the central nervous system (CNS), specifically the cortex and the retina. More precisely, we investigated the role of Bmi1, a polycomb family gene required for stem cell proliferation and self-renewal, in the development of the cerebral cortex, as well as in the genesis of the retina. These data, together with studies published during the last two decades concerning cell cycle re-activation in apoptotic neurons in the CNS, raised the question of a possible link between regulation of the cell cycle during development and during retinal degeneration. 1. The effects of Bmi1 loss in the cerebral cortex : Consistently with our and others' observations on failure of Bmi9-/- stem cells to proliferate and self-renew in vitro, the Bmi9-/- cerebral cortex presented slight defects in proliferation in stem/progenitor cells compartments in vivo. This was in accordance with the pattern of Bmi1 expression in the developing forebrain. The modest proliferation defects, compared to the drastic consequences of Bmi9 loss in vitro, suggest that cell-extrinsic mechanisms may partially compensate for Bmi1 deletion in vivo during cortical histogenesis. Nevertheless, we observed a decreased proliferating activity in neurogenic regions of the adult telencephalon, more precisely in the subventricular zone, showing that Bmi1 controls neural stem/progenitor proliferation during adulthood in vivo. Our data also highlight an increased production of astrocytes at birth, and a generalized gliosis in the adult Bmi9-/- brain. Importantly, glial progenitors and astrocytes retained the ability to proliferate in the absence of Bmi1. 2. The effects of Bmi1 loss in the retina : The pattern of expression of Bmi1 during development and in the adult retina suggests a role for Bmi1 in cell fate specification and differentiation rather than in proliferation. While the layering and the global structure of the retina appear normal in Bmi1 /adult mice, immunohistochemìcal analysis revealed defects in the three major classes of retinal interneurons, namely: horizontal, bipolar and amacrine cells. Electroretinogram recordings in Bmi9-/- mice are coherent with the defects observed at the histological level, with a reduced b-wave and low-profile oscillatory potentials. These results show that Bmi1 controls not only proliferation, but also cell type generation, as previously observed in the cerebellum. 3. Cell cycle events and related neuroprotective strategies in retinal degeneration : In several neurodegenerative disorders, neurons re-express cell cycle proteins such as cyclin dependent kinases (Cdks) prior to apoptosis. Here, we show for the first time that this is also the case during retinal degeneration. Rd1 mice carry a recessive defect (Pdeóbrd/rd) that causes retinal degeneration and serves as a model of retinitis pigmentosa. We found that photoreceptors express Cdk4 and Cdk2, and undergo DNA synthesis prior to cell death. To interfere with the reactivation of Cdk-related pathways, we deleted E2fs or Brni1, which normally allow cell cycle progression. While deleting E2f1 (downstream of Cdk4/6) in Rd1 mice provides only temporary protection, knocking out Bmi1 (upstream of Cdks) leads to an extensive neuroprotective effect, independent of p16ink4a or p19arf, two tumor suppressors regulated by Bmi1. Analysis of Cdks and the DNA repair-related protein Ligase IV showed that Bmi1 acts downstream of DNA repair events and upstream of Cdks in this neurodegenerative mechanism. Expression of Cdks during an acute model of retinal degeneration, light damage-induced photoreceptor death, points to a role for Bmi1 and cell cycle proteins in retinal degeneration. Considering the similarity with the cell cycle-related apoptotic pathway observed in other neurodegenerative diseases, Bmi1 is a possible general target to prevent or delay neuronal death. RESUME : Ce travail aborde plusieurs aspects de la régulation du cycle cellulaire, de la spécification du devenir des cellules et de la mort cellulaire dans le système nerveux centrale (SNC), plus particulièrement dans le cortex cérébral et dans la rétine. Nous nous sommes intéressés au gène Bmi1, appartenant à la famille polycomb et nécessaire à la prolifération et au renouvellement des cellules souches. Nous avons visé à disséquer son rôle dans le développement du cortex et de la rétine. Ces données, ainsi qu'une série de travaux publiés au cours des deux dernières décennies concernant la réactivation du cycle cellulaire dans les neurones en voie d'apoptose dans le SNC, nous ont ensuite poussé à chercher un lien entre la régulation du cycle cellulaire pendant le développement et au cours de la dégénérescence rétinienne. 1. Les effets de l'inactivation de Bmi1 dans le cortex cérébral : En accord avec l'incapacité des cellules souches neurales in vitro à proliférer et à se renouveler en absence de Bmi1, le cortex cérébral des souris Bmi1-/- présente de légers défauts de prolifération dans les compartiments contenant les cellules souches neurales. Ceci est en accord avec le profil d'expression de Bmi1 dans le télencéphale. Les conséquences de la délétion de Bmi1 sont toutefois nettement moins prononcées in vivo qu'in vitro ; cette différence suggère l'existence de mécanismes pouvant partiellement compenser l'absence de Bmi1 pendant la corticogenèse. Néanmoins, l'observation d'une réduction de la prolifération dans la zone sous-ventriculaire, la zone majeure de neurogenèse dans le télencéphale adulte, montre que Bmi1 contrôle la prolifération des cellules souche/progénitrices neurales chez la souris adulte. Nos résultats démontrent par ailleurs une augmentation de la production d'astrocytes à la naissance ainsi qu'une gliose généralisée à l'état adulte chez les souris Bmi1-/-. Les progéniteurs gliaux et les astrocytes conservent donc leur capacité à proliférer en absence de Bmi1. 2. Les effets de l'inactivation de Bmi1 dans la rétine : Le profil d'expression de Bmi1 pendant fe développement ainsi que dans la rétine adulte suggère un rôle de Bmi1 dans la spécification de certains types cellulaires et dans la différentiation plutôt que dans la prolifération. Alors que la structure et la lamination de la rétine semblent normales chez les souris Bmi1-/-, l'analyse par immunohistochimie amis en évidence des défauts au niveau des trois classes d'interneurones rétiniens (les cellules horizontales, bipolaires et amacrines). Les électrorétinogrammes des souris Bmi1-/- sont cohérents avec les défauts observés au niveau histologique et montrent une réduction de l'onde « b » et des potentiels oscillatoires. Ces résultats montrent que Bmi1 contrôle la génération de certaines sous-populations de neurones, comme démontré auparavant au niveau de cervelet. 3. Réactivation du cycle cellulaire et stratégies théraoeutiaues dans les dégénérescences rétiniennes : Dans plusieurs maladies neurodégénératives, les neurones ré-expriment des protéines du cycle cellulaire telles que les kinases cycline-dépendantes (Cdk) avant d'entrer en apoptose. Nous avons démontré que c'est aussi le cas dans les dégénérescences rétiniennes. Les souris Rd1 portent une mutation récessive (Pde6brd/rd) qui induit une dégénérescence de la rétine et sont utilisées comme modèle animal de rétinite pigmentaire. Nous avons observé que les photorécepteurs expriment Cdk4 et Cdk2, et entament une synthèse d'ADN avant de mourir par apoptose. Pour interférer avec la réactivation les mécanismes Cdk-dépendants, nous avons inactivé les gènes E2f et Bmi1, qui permettent normalement la progression du cycle cellulaire. Nous avons mis en évidence que la délétion de E2f1 (en aval de Cdk4/6) dans les souris Rd1 permet une protection transitoire des photorécepteurs. Toutefois, l'inactivation de Bmi1 (en amont des Cdk) est corrélée à une neuroprotection bien plus durable et ceci indépendamment de p16ink4a et p19arf, deux suppresseurs de tumeurs normalement régulés par Bmi1. L'analyse des Cdk et de la ligase IV (une protéine impliquée dans les mécanismes de réparation de l'ADN) a montré que Bmi1 agit en aval des événements de réparation de l'ADN et en amont des Cdk dans la cascade apoptotique dans les photorécepteurs des souris Rd1. Nous avons également observé la présence de Cdk dans un modèle aigu de dégénérescence rétinienne induit par une exposition des animaux à des niveaux toxiques de lumière. Nos résultats suggèrent donc un rôle général de Bmi1 et des protéines du cycle cellulaire dans les dégénérescences de la rétine. Si l'on considère la similarité avec les événements de réactivation du cycle cellulaire observés dans d'autres maladies neurodégénératives, Bmi1 pourrait être une cible thérapeutique générale pour prévenir la mort neuronale.

Workloads and strain process in Community Health Agents

ABSTRACT OBJECTIVE To identify the workloads present in the work activities of community health agents (CHAs) and the resulting strain processes. METHOD A descriptive, exploratory, cross-sectional and quantitative study conducted with 137 CHAs. Data were collected through a questionnaire and interview guided by the health surveillance software called SIMOSTE (Health Monitoring System of Nursing Workers), following the ethical codes of the current law. RESULTS In total, were identified 140 workloads involved in 122 strain processes, represented by the occurrence of health problems of the CHAs. The mechanical (55.00%) and biological (16.43%) loads stood out. The most common strain processes were the external causes of morbidity and mortality (62.31%) and diseases of the musculoskeletal system and connective tissue (10.66%). CONCLUSION From the identified overloads, it became evident that all workloads are present in the work process of CHAs, highlighting the mechanical load, represented mainly by external causes of morbidity and mortality that are related to occupational accidents.

Implementation study of a clinical prediction score to rule out cardiogenic chest pain in community: Cluster randomized trial

1.1 Fundamentals Chest pain is a common complaint in primary care patients (1 to 3% of all consultations) (1) and its aetiology can be miscellaneous, from harmless to potentially life threatening conditions. In primary care practice, the most prevalent aetiologies are: chest wall syndrome (43%), coronary heart disease (12%) and anxiety (7%) (2). In up to 20% of cases, potentially serious conditions as cardiac, respiratory or neoplasic diseases underlie chest pain. In this context, a large number of laboratory tests are run (42%) and over 16% of patients are referred to a specialist or hospitalized (2).¦A cardiovascular origin to chest pain can threaten patient's life and investigations run to exclude a serious condition can be expensive and involve a large number of exams or referral to specialist -­‐ often without real clinical need. In emergency settings, up to 80% of chest pains in patients are due to cardiovascular events (3) and scoring methods have been developed to identify conditions such as coronary heart disease (HD) quickly and efficiently (4-­‐6). In primary care, a cardiovascular origin is present in only about 12% of patients with chest pain (2) and general practitioners (GPs) need to exclude as safely as possible a potential serious condition underlying chest pain. A simple clinical prediction rule (CPR) like those available in emergency settings may therefore help GPs and spare time and extra investigations in ruling out CHD in primary care patients. Such a tool may also help GPs reassure patients with more common origin to chest pain.