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The RAS-MAPK pathway regulates cell proliferation, differentiation and survival, and its dysregulation is associated with cancer development. The pathway minimally comprises the small GTPase RAS and the kinases RAF, MEK and ERK. Activation of RAF by RAS is notoriously intricate and remains only partially understood. There are three RAF isoforms in mammals (ARAF, BRAF and CRAF) and two related pseudokinases (KSR1 and KSR2). RAS-mediated activation of RAF depends on an allosteric mechanism driven by the dimerization of its kinase domain. Recent work on human RAFs showed that MEK binding to KSR1 promotes KSR1-BRAF heterodimerization, which leads to the phosphorylation of free MEK molecules by BRAF. Similar findings were made with the single Drosophila RAF homolog. Here we show that the fly scaffold proteins CNK and HYP stabilize the KSR-MEK interaction, which in turn enhances RAF-KSR heterodimerization and RAF activation. The cryogenic electron microscopy structure of the minimal KSR-MEK-CNK-HYP complex reveals a ring-like arrangement of the CNK-HYP complex allowing CNK to simultaneously engage KSR and MEK, thus stabilizing the binary interaction. Together, these results illuminate how CNK contributes to RAF activation by stimulating the allosteric function of KSR and highlight the diversity of mechanisms impacting RAF dimerization as well as the regulatory potential of the KSR-MEK interaction., (© 2024. The Author(s).)

Purpose: To improve the quality of care for patients with breast cancer, an analysis of the health-care pathway, considering feedback from both health-care practitioners (HCPs) and patients, is needed., Methods: Between 2020 and 2022, we conducted a survey at French breast cancer centers and analyzed information from questionnaires completed by HCPs and patients. We collected information on center organization, diagnostic processes, treatment decisions and modalities, supportive care, patient advocacy groups, and work issues., Results: Twenty-three breast cancer centers were included and questionnaires completed by 247 HCPs and 249 patients were analyzed. The centers closely followed the legal French framework for cancer treatments, which includes formal diagnostic announcements, multidisciplinary tumor boards, personalized treatment summaries, and supportive care access. HCPs and patients were satisfied with the time to diagnosis (≤ 2 weeks as evaluated by 75% of patients), time to surgery (mean 61 days), time between surgery and chemotherapy (mean 47 days), and time between surgery and radiotherapy (mean 81 days). Fertility preservation counseling for women under 40 years of age was systematically offered by 67% of the HCPs. The majority (67%) of the patients indicated that they had received a personalized treatment summary; the topics discussed included treatments (92%), tumor characteristics (84%), care pathways (79%), supportive care (52%), and breast reconstruction (33%). Among HCPs, 44% stated that reconstructive surgery was offered to all eligible patients and 57% and 45% indicated coordination between centers and primary care physicians for adverse effects management and access to supportive care should be improved, for chemotherapy and radiotherapy, respectively. Regarding patient advocacy groups, 34% of HCPs did not know whether patients had contact and only 23% of patients declared that they had such contact. For one-third of working patients, work issues were not discussed. Twenty-eight percent of patients claimed that they had faced difficulties for supportive care access. Among HCPs, 13% stated that a formal personalized survivorship treatment program was administered to almost all patients and 37% almost never introduced the program to their patients. Compliance to oral treatments was considered very good for 75-100% of patients by 62% of HCPs., Conclusions: This study provides an updated analysis of breast cancer care pathways in France. Overall, the initial processes of diagnosis, announcement, and treatment were swift and were in agreement with the best care standards. No barriers to accessing care were identified. Based on the study findings, we proposed several strategies to improve the quality of care for patients in supportive care, coordination with primary care physicians, reconstructive surgery, and fertility preservation access., (© 2024. The Author(s).)

Background: The management of stage III non-small-cell lung cancer (NSCLC) remains heterogeneous and complex, even after the approval of immune checkpoint inhibitors post-chemoradiotherapy (CRT). This observational study from France evaluated real-world practices in managing stage III NSCLC., Methods: Between 2020 and 2022, we conducted a physician practice survey in 41 medical centers across France, and retrospectively analyzed aggregated information from 417 consecutive charts of patients with stage III NSCLC. We collected information on diagnostic and staging procedures, biomarker testing, surgical and non-surgical treatments, and follow-up., Results: According to the physician survey, diagnostic workup of stage III NSCLC primarily relied on positron emission tomography/computed tomography and brain magnetic resonance imaging, performed for the majority of patients in 100 % and 78 % of centers, respectively. Of 417 patient charts, 414 were evaluable with 53 % of patients having stage IIIA disease, 37 % IIIB, and 10 % IIIC. The most common node involvement was N2 (59 %). Programmed death-ligand 1 testing was conducted for 98 % of patients. Invasive staging (mediastinoscopy or endobronchial ultrasound) was performed in 41 % of patients, of whom 83 % had N2 or N3 nodal involvement. Surgical resection was offered to 120 patients (29 %), with 85 % achieving R0 resection. In 292 charts of patients with unresectable stage III NSCLC, 190 patients (65 %) were offered CRT followed by consolidation immunotherapy. Within these patients, concurrent CRT was more frequently employed (52 %) than sequential CRT (13 %)., Conclusions: Diagnostic procedures and treatment modalities in French medical centers generally align with clinical guidelines for stage III NSCLC, except for invasive staging that was less commonly performed than expected., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Jean-Bernard Auliac reports financial support was provided by AstraZeneca. Jean-Bernard Auliac reports a relationship with AstraZeneca that includes: consulting or advisory, paid expert testimony, speaking and lecture fees, and travel reimbursement. Jean-Bernard Auliac reports a relationship with Takeda Pharmaceutical Company Limited that includes: consulting or advisory and paid expert testimony. Jean-Bernard Auliac reports a relationship with Bristol Myers Squibb Co that includes: consulting or advisory, paid expert testimony, and travel reimbursement. Jean-Bernard Auliac reports a relationship with Janssen Pharmaceuticals Inc that includes: consulting or advisory, paid expert testimony, and speaking and lecture fees. Jean-Bernard Auliac reports a relationship with Amgen Inc that includes: consulting or advisory, paid expert testimony, and speaking and lecture fees. Jean-Bernard Auliac reports a relationship with MSD France SAS that includes: speaking and lecture fees and travel reimbursement. Jean-Bernard Auliac reports a relationship with Sanofi that includes: paid expert testimony, speaking and lecture fees, and travel reimbursement. Jean-Bernard Auliac reports a relationship with Boehringer Ingelheim GmbH that includes: travel reimbursement. Laurent Greillier reports a relationship with Bristol Myers Squibb Co that includes: funding grants and speaking and lecture fees. Laurent Greillier reports a relationship with MSD France SAS that includes: funding grants, speaking and lecture fees, and travel reimbursement. Laurent Greillier reports a relationship with Takeda Pharmaceutical Company Limited that includes: funding grants, speaking and lecture fees, and travel reimbursement. Laurent Greillier reports a relationship with Pfizer that includes: funding grants, speaking and lecture fees, and travel reimbursement. Laurent Greillier reports a relationship with Roche that includes: funding grants and speaking and lecture fees. Laurent Greillier reports a relationship with Amgen Inc that includes: funding grants and speaking and lecture fees. Laurent Greillier reports a relationship with Sanofi that includes: funding grants and speaking and lecture fees. Laurent Greillier reports a relationship with Janssen Pharmaceuticals Inc that includes: funding grants and speaking and lecture fees. Laurent Greillier reports a relationship with Eli Lilly and Company that includes: funding grants and speaking and lecture fees. Laurent Greillier reports a relationship with Novartis that includes: funding grants and speaking and lecture fees. Laurent Greillier reports a relationship with AstraZeneca that includes: travel reimbursement. Etienne Martin reports a relationship with AstraZeneca that includes: consulting or advisory, speaking and lecture fees, and travel reimbursement. Etienne Martin reports a relationship with Varian Medical Systems Inc that includes: speaking and lecture fees. Etienne Martin reports a relationship with Sanofi that includes: speaking and lecture fees. Etienne Martin reports a relationship with Ipsen that includes: speaking and lecture fees and travel reimbursement. Etienne Martin reports a relationship with MSD France SAS that includes: speaking and lecture fees. Etienne Martin reports a relationship with Janssen Pharmaceuticals Inc that includes: consulting or advisory and travel reimbursement. Sabine Ano reports a relationship with AstraZeneca that includes: employment. Marc Lefrancois reports a relationship with CMI Group that includes: employment and equity or stocks. Marc Lefrancois reports a relationship with AstraZeneca that includes: consulting or advisory. Alexis Cortot reports a relationship with Roche that includes: funding grants and paid expert testimony. Alexis Cortot reports a relationship with Novartis that includes: consulting or advisory, paid expert testimony, speaking and lecture fees, and travel reimbursement. Alexis Cortot reports a relationship with Sanofi that includes: speaking and lecture fees. Alexis Cortot reports a relationship with Pfizer that includes: paid expert testimony and speaking and lecture fees. Alexis Cortot reports a relationship with Takeda Pharmaceutical Company Limited that includes: paid expert testimony, speaking and lecture fees, and travel reimbursement. Alexis Cortot reports a relationship with Janssen Pharmaceuticals Inc that includes: paid expert testimony. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 SPLF and Elsevier Masson SAS. All rights reserved.)

Cell motility is a critical feature of invasive tumour cells that is governed by complex signal transduction events. Particularly, the underlying mechanisms that bridge extracellular stimuli to the molecular machinery driving motility remain partially understood. Here, we show that the scaffold protein CNK2 promotes cancer cell migration by coupling the pro-metastatic receptor tyrosine kinase AXL to downstream activation of ARF6 GTPase. Mechanistically, AXL signalling induces PI3K-dependent recruitment of CNK2 to the plasma membrane. In turn, CNK2 stimulates ARF6 by associating with cytohesin ARF GEFs and with a novel adaptor protein called SAMD12. ARF6-GTP then controls motile forces by coordinating the respective activation and inhibition of RAC1 and RHOA GTPases. Significantly, genetic ablation of CNK2 or SAMD12 reduces metastasis in a mouse xenograft model. Together, this work identifies CNK2 and its partner SAMD12 as key components of a novel pro-motility pathway in cancer cells, which could be targeted in metastasis., (© 2023. The Author(s).)

Objective: Conducting participatory research (PR) aimed at improving health implies considering inequitable power relations, including those related to sex/gender (S/G). This necessitates specific skills and methods and may be challenging especially since guidelines are scarce. Our objective was to perform a scoping review to provide a typology of existing guidelines for researchers on how to take account of S/G in the context of PR in public health, with a focus on occupational and environmental health., Methods: All steps of the research were conducted with the collaboration of an advisory committee, following PR principles. Nineteen documents were retained from 513 references identified in nine scientific databases and grey literature between 2000 and 2020. Data on recommendations were extracted and coded qualitatively. Cluster analysis based on similarities in recommendations proposed in the documents identified four types: (1) empowerment-centered; (2) concrete action-centered; (3) macrosystem-centered; and (4) stakeholder-centered., Synthesis: Many sources gave pointers on how to include S/G during data collection and analysis or during the dissemination of findings, but there was a dearth of suggestions for building partnerships with stakeholders and producing sustainable S/G sociopolitical transformations. Occupational health PR showed less similarities with other public health subfields including environmental health PR. Power relationships with workplace stakeholders generated specific obstacles related to S/G integration that require further attention. Intersectionality and reflexive practices emerged as overarching themes., Conclusion: This review provides helpful guidelines to researchers at different stages of planning PR, ranging from familiarizing themselves with S/G approaches to anticipating difficulties in their ongoing S/G-transformative PR., (© 2023. The Author(s) under exclusive license to The Canadian Public Health Association.)

This article aims to analyse the integration of sex and gender (s/g) by ergonomics students during their internship at the master's degree level, following training sessions on s/g issues in the workplace. This exploratory research used a descriptive mixed-methods design, encompassing evaluation of students' intention to use the content from the training ( n  = 13 students), and a multiple case study ( n  = 5 ergonomics interventions). The results show that while students found the training relevant, they only minimally integrated s/g in their interventions and when they did, it was primarily from an anthropometric and physiological perspective. In addition to discussing the training format limitations, the article discusses barriers to this integration: combining learning about s/g issues with learning about activity analysis is challenging; employers' and workers' organisations may be reluctant to approach s/g issues; and it is difficult for an ergonomist to integrate these issues when the employer's request does not specify it. Practitioner summary: This article aims to analyse the integration of s/g by ergonomics students during their internships. Findings show that they only minimally considered s/g. The discussion examines s/g training, organisational obstacles to inclusion of s/g during interventions, and how ergonomists can consider s/g in their practice.

Work-family balance (WFB) in the construction sector has rarely been studied. Hardship, atypical schedules and seasonal work create challenging conditions for parents in this male-dominated industry. Semi-structured interviews with workers (14 men, 6 women) and a survey of 789 on-site workers (85% men, 15% women) were conducted as part of a wider participatory action-research project involving governmental actors. Triangulation of the interview and survey data clarified the influence of quantitative and qualitative workload and of managerial support on work-family conflict. Results also show that male and female workers have differentiated experiences of WF issues and, consequently, develop different WF strategies while pursuing increased flexibility. The stereotyped conception of WF encourages social norms that have various impacts on mothers and fathers working in the industry. Recommendations for a cultural shift are proposed for employers in this industry, marked by a labour shortage and low retention of female workers. Practitioner summary: This paper provides a gendered analysis of work-family issues among on-site workers in the construction industry. It aims to inform ergonomists and occupational health researchers about the potential of inflexible work designs to convey stereotypes that can impact the sustainability and equity of workplace interventions.

Dendritic cells (DCs) encompass several cell subsets that collaborate to initiate and regulate immune responses. Proper DC localization determines their function and requires the tightly controlled action of chemokine receptors. All DC subsets express CXCR4, but the genuine contribution of this receptor to their biology has been overlooked. We addressed this question using natural CXCR4 mutants resistant to CXCL12-induced desensitization and harboring a gain of function that cause the warts, hypogammaglobulinemia, infections, and myelokathexis (WHIM) syndrome (WS), a rare immunodeficiency associated with high susceptibility to the pathogenesis of human papillomavirus (HPV). We report a reduction in the number of circulating plasmacytoid DCs (pDCs) in WHIM patients, whereas that of conventional DCs is preserved. This pattern was reproduced in an original mouse model of WS, enabling us to show that the circulating pDC defect can be corrected upon CXCR4 blockade and that pDC differentiation and function are preserved, despite CXCR4 dysfunction. We further identified proper CXCR4 signaling as a critical checkpoint for Langerhans cell and DC migration from the skin to lymph nodes, with corollary alterations of their activation state and tissue inflammation in a model of HPV-induced dysplasia. Beyond providing new hypotheses to explain the susceptibility of WHIM patients to HPV pathogenesis, this study shows that proper CXCR4 signaling establishes a migration threshold that controls DC egress from CXCL12-containing environments and highlights the critical and subset-specific contribution of CXCR4 signal termination to DC biology., (© 2021 by The American Society of Hematology.)

Background: Acute diverticulitis is a common disease with public health significance. Many studies with a high level of evidence have been published recently on the surgical management of acute diverticulitis., Objective: The aim of this systematic review was to define the accurate surgical management of acute diverticulitis., Data Sources: Medline, Embase, and the Cochrane Library were sources used., Study Selection: One reviewer conducted a systematic study with combinations of key words for the disease and the surgical procedure. Additional studies were searched in the reference lists of all included articles. The results of the systematic review were submitted to a working group composed of 13 practitioners. All of the conclusions were obtained by full consensus and validated by an external committee., Interventions: The interventions assessed were laparoscopic peritoneal lavage, primary resection with anastomosis with or without ileostomy, and the Hartmann procedure, with either a laparoscopic or an open approach., Main Outcome Measures: Morbidity, mortality, long-term stoma rates, and quality of life were measured., Results: Seventy-one articles were included. Five guidelines were retrieved, along with 4 meta-analyses, 14 systematic reviews, and 5 randomized controlled trials that generated 8 publications, all with a low risk of bias, except for blinding. Laparoscopic peritoneal lavage showed concerning results of deep abscesses and unplanned reoperations. Studies on Hinchey III/IV diverticulitis showed similar morbidity and mortality. A reduced length of stay with Hartmann procedure compared with primary resection with anastomosis was reported in the short term, and in the long term, more definite stoma along with poorer quality of life was reported with Hartmann procedure. No high-quality data were found to support the laparoscopic approach., Limitations: Trials specifically assessing Hinchey IV diverticulitis have not yet been completed., Conclusions: High-quality studies showed that laparoscopic peritoneal lavage was associated with an increased morbidity and that Hartmann procedure was associated with poorer long-term outcomes than primary resection with anastomosis with ileostomy, but Hartmann procedure is still acceptable, especially in high-risk patients.

For parents working in the transportation industry, atypical schedules are often a daily puzzle. Schedule planning systems allowing workers to choose shifts may affect job strenuousness and work-family balance (WFB) for both female and male workers. How could ergonomic interventions related to the implementation of those systems better consider gender dynamics regarding WFB strategies, and minimize inequities among workers? This article presents a joint analysis of two independent case studies related to ergonomic interventions in transport companies in Canada and Switzerland. Direct observation and semi-structured interviews shed light on the characteristics of schedule planning systems and their interaction with men's and women's WFB strategies. Issues related to each step of the planning process (shift construction, schedule choice, day-to-day schedule management) are discussed to inform interventions aimed at facilitating WFB, and ultimately gender equity, in atypical schedule contexts., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The aim of this article is to examine the impacts of incorporating sex and gender (s/g) analysis in integrated knowledge translation (iKT) initiatives in the field of ergonomics and occupational health. The article presents findings based on a retrospective analysis of twelve intervention-research (IR) studies, including a thematic content analysis of in-depth interviews conducted with 15 researchers involved in these IRs. The findings offer an overview of various categories of impacts, such as changes in partners' views, in workplace settings and conditions, in practices and policies, and in economic outcomes. In these types of IR, health effects measurement is not the main objective, and direct health outcomes are difficult to assess. Explicitly talking about sex/gender led more often to system-level changes but less often to workplace-level changes, compared to interventions where sex/gender was not identified as a specific object of the intervention., (Crown Copyright © 2019. Published by Elsevier Ltd. All rights reserved.)

Whether or not official work/family balance measures exist within an organization, scheduling accommodations often go through informal channels involving colleagues and superiors and are negotiated within interpersonal relationships. This study examines the relationship dimensions of the scheduling strategies of cleaners working atypical hours in the transport sector through the lenses of ergonomic activity, network, and gender analyses. Using semi-directed interviews, observation, and network analysis, we revealed the effect of gender on relationship dynamics and the influence of these dynamics on work/family balance strategies deployed by cleaners. One of the main contributions of this study is to demonstrate the decisive effect of relationships by revealing inequalities in access to organizational social networks. Creating spaces to discuss work/family balancing and a more equitable circulation of information could contribute to reducing inequalities associated with gender, social status, and family responsibilities and support the work/family strategies developed by workers dealing with restrictive work schedules. Résumé Les accommodements du temps de travail pour la conciliation travail-famille (CTF) passent souvent par des ententes informelles qui s'inscrivent dans les relations entre collègues ou avec des gestionnaires. Notre étude, intégrant l'ergonomie et la communication dans une perspective de genre, porte sur les dimensions relationnelles des stratégies de choix d'horaire d'agentes et agents de nettoyage devant composer avec des horaires atypiques dans le secteur des transports. À partir d'entretiens semi-dirigés, d'observations et d'analyse de réseaux, nous avons pu observer l'influence des dynamiques relationnelles, notamment de genre, sur les stratégies de CTF. Un apport central de cette étude est de montrer l'effet structurant des relations en révélant notamment des inégalités dans l'accès aux ressources facilitant le choix d'horaire, mais aussi dans l'inclusion au sein du réseau de relations. L'article conclut en proposant des pistes de solutions concrètes pour la réduction de ces inégalités.

The CXCR4 receptor binds with meaningful affinities only CXCL12 and synthetic antagonists/inverse agonists. We recently described high affinity synthetic agonists for this chemokine receptor, obtained by grafting the CXCL12 N-terminus onto the inverse agonist T140. While those chimeric molecules behave as agonists for CXCR4, their binding and activation mode are unknown. The present SAR of those CXCL12-oligopeptide grafts reveals the key determinants involved in CXCR4 activation. Position 3 (Val) controls affinity, whereas position 7 (Tyr) acts as an efficacy switch. Chimeric molecules bearing aromatic residues in position 3 possess high binding affinities for CXCR4 and are Gαi full agonists with robust chemotactic properties. Fine-tuning of electron-poor aromatic rings in position 7 enhances receptor activation. To rationalize these results, a homology model of a receptor-ligand complex was built using the published crystal structures of CXCR4. Molecular dynamics simulations reveal further details accounting for the observed SAR for this series.

To date, very little is known about the normal development trajectory of visual texture segregation, or how it is affected by preterm birth. The goal of this study was to characterize the development of visual texture segregation using texture segregation visual evoked potentials (tsVEPs) in children born full-term and children born preterm without major neurological impairment. Forty-five full-term and 43 preterm children were tested at either 12, 24 or 36 months of age (corrected age for prematurity at 12 and 24 months old). VEPs were obtained using two lower-level stimuli defined by orientation (oriVEP) and two higher-level stimuli defined by texture (texVEP). TsVEP was obtained by dividing by two the subtraction of oriVEP from texVEP. Results show a clear maturation of the processes underlying visual texture segregation in the full-term group, with a significant N2 latency reduction between 12 and 36 months of age for all conditions. Significant N2 amplitude reduction was observed for oriVEP between 12 and 24 months, as well as for texVEP between 12 and 24 months, and 12 and 36 months. Comparison between full-term and preterm children indicated significantly lower N2 amplitude for the preterm group at 12 months for oriVEP and texVEP. These differences were no longer apparent at 24 months of age, suggesting that children born preterm catch up with their full-term counterparts somewhere between 12 and 24 months of age. Our results appear to reflect a maturational delay in preterm children in both lower-level and higher-level visual processing during, at least, early childhood., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Aim: Total/subtotal colectomy with ileorectal (IRA) or ileosigmoid (ISA) anastomosis is associated with various reported rates of morbidity, function and quality of life. Our object was to determine these end-points in a series of patients undergoing these operations in our institution., Method: All patients who underwent IRA or ISA between 1994 and 2009 were retrospectively reviewed., Results: A total of 320 patients (female 49%) with a median age of 54.2 (16.8-90.6) years underwent 338 IRA or ISA (in 18 patients the anastomosis was done twice) for inflammatory bowel disease (n = 96), polyposis (n = 95) and colorectal cancer (n = 97). Mortality and morbidity rates were 1.2% (n = 4) and 19.5% (n = 66) and 47 surgical complications (13.9%) occurred, including 26 (7.7%) cases of anastomotic leakage, leading to 23 re-operations. After a median follow-up of 49 (0-196) months, 262 patients still had a functioning anastomosis; 45 patients had died and 13 had a proctectomy. Information on function was obtained in 51.4% (133/259) of the cohort after a median follow-up of 77 (10-196) months. The mean (± standard deviation) rates of 24 h and nocturnal defaecation were 3.6 ± 2.4 and 0.5 ± 0.9. A disturbance of faecal or flatus continence occurred in 20% and 21% of patients. There was no case of faecal incontinence to solid stool. The mean SF-36 Physical and Mental Health Summary Scales were 46.3 ± 9.3 and 51.9 ± 9.3. Multivariate analysis showed that IRA and inflammatory bowel disease were both independently associated with poorer long-term function., Conclusion: Colectomy with IRA or ISA is safe with low postoperative morbidity and mortality. The employment of IRA and inflammatory bowel disease appear to be independent negative factors on function in multivariate analysis., (Colorectal Disease © 2014 The Association of Coloproctology of Great Britain and Ireland.)

The Ras/MAPK-signaling pathway plays pivotal roles during development of metazoans by controlling cell proliferation and cell differentiation elicited, in several instances, by receptor tyrosine kinases (RTKs). While the internal mechanism of RTK-driven Ras/MAPK signaling is well understood, far less is known regarding its interplay with other co-required signaling events involved in developmental decisions. In a genetic screen designed to identify new regulators of RTK/Ras/MAPK signaling during Drosophila eye development, we identified the small GTPase Rap1, PDZ-GEF, and Canoe as components contributing to Ras/MAPK-mediated R7 cell differentiation. Rap1 signaling has recently been found to participate in assembling cadherin-based adherens junctions in various fly epithelial tissues. Here, we show that Rap1 activity is required for the integrity of the apical domains of developing photoreceptor cells and that reduced Rap1 signaling hampers the apical accumulation of the Sevenless RTK in presumptive R7 cells. It thus appears that, in addition to its role in cell-cell adhesion, Rap1 signaling controls the partitioning of the epithelial cell membrane, which in turn influences signaling events that rely on apico-basal cell polarity., (Copyright © 2014 by the Genetics Society of America.)

The small GTPase RAS is among the most prevalent oncogenes. The evolutionarily conserved RAF-MEK-MAPK module that lies downstream of RAS is one of the main conduits through which RAS transmits proliferative signals in normal and cancer cells. Genetic and biochemical studies conducted over the last two decades uncovered a small set of factors regulating RAS/MAPK signaling. Interestingly, most of these were found to control RAF activation, thus suggesting a central regulatory role for this event. Whether additional factors are required at this level or further downstream remains an open question. To obtain a comprehensive view of the elements functionally linked to the RAS/MAPK cascade, we used a quantitative assay in Drosophila S2 cells to conduct a genome-wide RNAi screen for factors impacting RAS-mediated MAPK activation. The screen led to the identification of 101 validated hits, including most of the previously known factors associated to this pathway. Epistasis experiments were then carried out on individual candidates to determine their position relative to core pathway components. While this revealed several new factors acting at different steps along the pathway--including a new protein complex modulating RAF activation--we found that most hits unexpectedly work downstream of MEK and specifically influence MAPK expression. These hits mainly consist of constitutive splicing factors and thereby suggest that splicing plays a specific role in establishing MAPK levels. We further characterized two representative members of this group and surprisingly found that they act by regulating mapk alternative splicing. This study provides an unprecedented assessment of the factors modulating RAS/MAPK signaling in Drosophila. In addition, it suggests that pathway output does not solely rely on classical signaling events, such as those controlling RAF activation, but also on the regulation of MAPK levels. Finally, it indicates that core splicing components can also specifically impact alternative splicing., Competing Interests: The authors have declared that no competing interests exist.

During child development, physiological changes occur in the auditory cortex, which are reflected by differences in the electrophysiological signals. This study aimed to examine the age-related changes of the Mismatch Negativity component (MMN) in response to speech and non-speech stimuli in a cross-sectional design. Results revealed distinct patterns of activation according to stimulus type and age. Age-related differences for tone discrimination occurred earlier in children's development than did the discriminative process for speech sounds. Therefore, networks involved in speech processing are still immature in late childhood and may be more vulnerable to physiological changes.

Functional near-infrared spectroscopy (fNIRS) has become increasingly established as a promising technique for monitoring functional brain activity. To our knowledge, no study has yet used fNIRS to investigate overt reading of irregular words and nonwords with a full coverage of the cerebral regions involved in reading processes. The aim of our study was to design and validate a protocol using fNIRS for the assessment of overt reading. Twelve healthy French-speaking adults underwent one session of fNIRS recording while performing an overt reading of 13 blocks of irregular words and nonwords. Reading blocks were separated by baseline periods during which participants were instructed to fixate a cross. Sources (n = 55) and detectors (n = 16) were placed bilaterally over frontal, temporal, parietal, and occipital regions. Two wavelengths were used: 690 nm, more sensitive to deoxyhemoglobin (HbR) concentration changes, and 830 nm, more sensitive to oxyhemoglobin (HbO) concentration changes. For all participants, total hemoglobin (HbT) concentrations (HbO + HbR) were significantly higher than baseline for both irregular word and nonword reading in the inferior frontal gyri, the middle and superior temporal gyri, and the occipital cortices bilaterally. In the temporal gyri, although the difference was not significant, [HbT] values were higher in the left hemisphere. In the bilateral inferior frontal gyri, higher [HbT] values were found in nonword than in irregular word reading. This activation could be related to the grapheme-to-phoneme conversion characterizing the phonological pathway of reading. Our findings confirm that fNIRS is an appropriate technique to assess the neural correlates of overt reading.

The development of agonists for the chemokine receptor CXCR4 could provide promising therapeutic candidates. On the basis of previously forwarded two site model of chemokine-receptor interactions, we hypothesized that linking the agonistic N-terminus of SDF-1 to the T140 backbone would yield new high-affinity agonists of CXCR4. We developed chimeras with the agonistic SDF-1 N-terminus grafted to a T140 side chain and tested their binding affinity and chemotactic agonist activity. While chimeras with the peptide grafted onto position 12 of T140 remained high-affinity antagonists, those bearing the peptide on position 14 were in part agonists. One chimera was a full CXCR4 agonist with 25 nM affinity, and several chimeras showed low nanomolar affinities with partial agonist activity. Our results confirmed that we have developed high-affinity agonists of CXCR4.

Most antipsychotic (AP) drugs are dopamine (DA) D2 receptor (DRD2) antagonists and remain the main pharmacological treatment of schizophrenia. Long-term AP use can give rise to tardive dyskinesia. It has been reported that chronic treatment with APs induces DRD2 upregulation and oxidative stress, which have been associated with tardive dyskinesia. We showed previously that H₂O₂-induced oxidative stress increased DRD2 expression in human SH-SY5Y neuroblastoma cells. We report here the effects of AP drugs on DRD2 expression levels in the same cell line and the effects of the inhibition of oxidative phenomena by (±)-α-lipoic acid treatment. Haloperidol, a first-generation AP, induced an increase in DRD2 protein and mRNA levels, whereas amisulpride, a second-generation AP, had no significant effect. (±)-α-Lipoic acid pretreatment reversed the haloperidol-induced DRD2 upregulation in mRNA and protein levels. Furthermore, haloperidol induced a larger increase of oxidative stress biomarkers (protein carbonylation, lipid peroxidation, and superoxide anion production) than amisulpride. (±)-α-Lipoic acid also attenuated AP-induced oxidative stress. Inhibition of catecholamine synthesis by α-methyl-DL-tyrosine (AMPT) increased DRD2 expression and prevented further increase by APs. Our results suggest that haloperidol-induced DRD2 upregulation is linked to oxidative stress and provide potential mechanisms by which (±)-α-lipoic acid can be considered as a therapeutic agent to prevent and treat side effects related to the use of first-generation APs., (Copyright © 2010 Wiley-Liss, Inc.)

Signaling pathways are controlled by a vast array of posttranslational mechanisms. By contrast, little is known regarding the mechanisms that regulate the expression of their core components. We conducted an RNAi screen in Drosophila for factors modulating RAS/MAPK signaling and identified the Exon Junction Complex (EJC) as a key element of this pathway. The EJC binds the exon-exon junctions of mRNAs and thus far, has been linked exclusively to postsplicing events. Here, we report that the EJC is required for proper splicing of mapk transcripts by a mechanism that apparently controls exon definition. Moreover, whole transcriptome and RT-PCR analyses of EJC-depleted cells revealed that the splicing of long intron-containing genes, which includes mapk, is sensitive to EJC activity. These results identify a role for the EJC in the splicing of a subset of transcripts and suggest that RAS/MAPK signaling depends on the regulation of MAPK levels by the EJC., (Copyright © 2010 Elsevier Inc. All rights reserved.)

The ERK (extracellular signal-regulated kinase) pathway is an evolutionarily conserved signal transduction module that controls cellular growth, differentiation and survival. Activation of receptor tyrosine kinases (RTKs) by the binding of growth factors initiates GTP loading of RAS, which triggers the initial steps in the activation of the ERK pathway by modulating RAF family kinase function. Once activated, RAF participates in a sequential cascade of phosphorylation events that activate MEK, and in turn ERK. Unbridled signalling through the ERK pathway caused by activating mutations in RTKs, RAS or RAF has been linked to several human cancers. Of note, one member of the RAF family, BRAF, is the most frequently mutated oncogene in the kinase superfamily. Not surprisingly, there has been a colossal effort to understand the underlying regulation of this family of kinases. In particular, the process by which the RAF kinase domain becomes activated towards its substrate MEK remains of topical interest. Here, using Drosophila Schneider S2 cells, we demonstrate that RAF catalytic function is regulated in response to a specific mode of dimerization of its kinase domain, which we term the side-to-side dimer. Moreover, we find that the RAF-related pseudo-kinase KSR (kinase suppressor of Ras) also participates in forming side-to-side heterodimers with RAF and can thereby trigger RAF activation. This mechanism provides an elegant explanation for the longstanding conundrum about RAF catalytic activation, and also provides an explanation for the capacity of KSR, despite lacking catalytic function, to directly mediate RAF activation. We also show that RAF side-to-side dimer formation is essential for aberrant signalling by oncogenic BRAF mutants, and identify an oncogenic mutation that acts specifically by promoting side-to-side dimerization. Together, our data identify the side-to-side dimer interface of RAF as a potential therapeutic target for intervention in BRAF-dependent tumorigenesis.

We propose a numerical method to accurately discriminate the influence of the different intrachannel nonlinear effects occurring in 40 Gbit/s optical transmissions, following an analogy with methods used to discriminate WDM interchannel effects. In contrast to other studies showing the predominance of intrachannel cross-phase modulation when low-dispersion fibers are used, in our study intrachannel four-wave mixing is the most penalizing effect in all investigated cases.

Connector enhancer of KSR (CNK) is a multidomain-containing protein previously identified as a positive regulator of the RAS/MAPK pathway in Drosophila. Using transfection experiments and an RNAi-based rescue assay in Drosophila S2 cells, we demonstrate that CNK has antagonistic properties with respect to RAF activity. We show that CNK's N-terminal region contains two domains (SAM and CRIC) that are essential for RAF function. Unexpectedly, we also report that the C-terminal region of CNK contains a short bipartite element that strongly inhibits RAF catalytic function. Interestingly, CNK's opposite properties appear to prevent signaling leakage from RAF to MEK in the absence of upstream signals, but then transforms into a potent RAF activator upon signal activation. Together, these findings suggest that CNK not only participates in the elusive RAF activation process, but might also contribute to the switch-like behavior of the MAPK module.

Purpose: To assess visual functioning and other health-related quality of life outcomes after corneal grafting., Design: A cohort study of corneal graft recipients observed for a minimum of 2 years after transplantation., Methods: Repeated measurements were obtained by telephone interviews preoperatively and later at 1 and 2 years post-corneal transplantation in 217 patients with the following questionnaires: visual function index (VF-14), visual symptom score and global measures of trouble with vision, dissatisfaction with vision, ocular pain, and discomfort. Demographic, past ocular history, repeated best-corrected visual acuity (BCVA), and detailed eye examination data were also collected., Results: Grafted eyes gained a mean of more than four lines of vision on the Early Treatment Diabetic Retinopathy Study (ETDRS) chart 1 year after transplantation. The mean visual function index (VF-14) score improved from 68% +/- 26% preoperatively to 81% +/- 21% at 1 year. Average visual acuity (VA) and VF-14 values were unchanged at 2 years. The activities of daily living that showed the largest and most significant improvement were reading small print, driving in daytime, and watching television. A number of subjects (9%) presented with a maximum VF-14 score preoperatively, leaving no room for improvement with this outcome index. The VF-14 was especially responsive for corneal graft candidates with low levels of vision before surgery. Blurry vision, pain and discomfort scores, and the global measures of trouble and dissatisfaction with vision also improved after corneal grafting., Conclusion: The VF-14 index of functional visual impairment is a responsive and useful outcome index in recipients of a corneal graft.

The presence of apurinic/apyrimidinic (AP) sites in cell genomes is known to be toxic and mutagenic. These lesions are therefore repaired in cells by efficient enzymatic systems. However, a report (Nakamura and Swenberg, Cancer Res. 59 (1999) 2522-2526) indicates an unexpected high rate of endogenous apurinic/apyrimidinic (AP) sites in genomic DNA in mammalian tissues. The technology used does not allow the authors to distinguish between intact AP sites and 3'cleaved AP sites. The corresponding values range between 2 and 4 sites per million of nucleotides in various human and rat tissues. Using a modified alkaline elution method we show here that the stationary level of intact AP sites is about 0.16 per million of nucleotides in leukemic mouse L1210 cells.

Purpose: To validate the Visual Function-14 (VF-14) index of functional visual impairment in candidates for a corneal graft., Methods: One hundred thirty-four patients who were candidates for a corneal graft participated in this study between August 1996 and February 1997. Demographic, ocular history, best-corrected visual acuity, and detailed ocular examination data were collected. Functional visual impairment information was obtained by telephone interviews using the following: VF-14, SF-36 (Short Form-36, a more generic measure of general health function), and Visual Symptom Score, and four questions measuring the overall amount of trouble with vision, dissatisfaction with vision, ocular pain, and discomfort., Results: The average age of corneal graft candidates was 64 +/- 18 years (range, 18 to 90 years) and 60% were women. The most frequent corneal disease was pseudophakic bullous keratopathy (41%). Ocular comorbidities included glaucoma or ocular hypertension (30%) and cataract (19%). The mean best-corrected visual acuity of the eye scheduled for surgery was 1.33 +/- 0.56 logMAR whereas the best eye best-corrected visual acuity was 0.36 +/- 0.44 logMAR. The mean VF-14 score was 73% +/- 26%, and the internal consistency was high, with a Cronbach alpha value of 0.94. The VF-14 correlated strongly with the best eye best-corrected visual acuity. It also correlated strongly with the Visual Symptom Score, the global measures of trouble and dissatisfaction with vision. Candidates for a corneal graft had low scores for all eight general health concepts evaluated with the SF-36, and the VF-14 correlated with seven of the eight SF-36 subscales., Conclusion: The VF-14 is a valid measure of functional visual impairment in candidates for a corneal graft. The Visual Symptom Score and the SF-36 are also useful indices in such patients.

Objective: To evaluate the therapeutic effects of anterior stromal punctures (ASP) in patients with bullous keratopathy (BK)., Patients and Methods: Twenty-seven patients awaiting penetrating keratoplasty with a diagnosis of BK were examined. They were seen before treatment with ASP and 1, 4, and 12 weeks after treatment. The examination included slit-lamp examination, photography of the cornea, ultrasonic pachymetry, central esthesiometry, and pneumotonometry. Subjective evaluations of pain, discomfort, and photophobia were also done using a visual scale model. Photographs were analyzed by computer-assisted planimetry and used to measure the corneal surface covered by bullae and microcysts. Pretreatment and posttreatment values (mean +/- SEM) were compared using the Student paired t test., Results: At 3 months, a significant reduction in pain was noted. A decrease in the mean corneal surface covered by bullae (BKPreASP = 2733 +/- 553 microns2; BK3mo = 1006 +/- 356 microns2, P = .004) was observed. A decrease in the esthesiometry (E) measurement (EPreASP = 3.5 +/- 0.4 cm; E3mo = 1.3 +/- 0.3 cm, P < .001), an increase in corneal thickness ([CT] CTPreASP = 869 +/- 24 microns; CT3mo = 902 +/- 21 microns, P < .001), and a decrease in the number of quadrants through which iris (I) details could be seen (IPreASP = 1.7 +/- 0.3; I3mo = 1.2 +/- 0.3, P = .015) were also noted. These findings corroborate the clinical observation of increased subepithelial fibrosis following ASP., Conclusions: Anterior stromal punctures reduce bullae formation and alleviate pain in patients with BK, and they constitute a valuable alternative to penetrating keratoplasty should surgery be delayed or contraindicated.

The aromatic amine 9-amino-ellipticine is a synthetic DNA intercalating compound derived from the antitumor agent ellipticine, which cleaves at very low doses DNA containing apurinic sites by beta-elimination through formation of a Schiff base. This compound has been shown to potentiate the cytotoxic effect of alkylating drugs, such as dimethyl sulfate, in E. coli through a mechanism involving apurinic sites. We have studied the ability of 9-amino-ellipticine to inhibit an enzymatic repair system mimicking base-excision repair, in which E. coli exonuclease III only presents an endonuclease for apurinic/apyrimidinic site activity. 10 microM of 9-amino-ellipticine inhibits 70% of apurinic site repair. Other intercalating agents with similar affinities for DNA do not induce any inhibition. In another system designed for the direct assay of the exonuclease III-induced incisions 5' to AP sites 10 microM of 9-amino-ellipticine inhibits 65% of the endonuclease for apurinic/apyrimidinic site activity of E. coli exonuclease III. The 9-amino-ellipticine-induced formation of a 2',3'-unsaturated deoxyribose and cleavage at the 3' side of the apurinic site, and possible creation of an adduct, as suggested by Bertrand and coworkers (1989), on the 3' position of the deoxyribose seem to strongly inhibit the endonuclease for apurinic/apyrimidinic site activity. 9-Amino-ellipticine appears therefore to be the first small ligand which can inhibit, by an irreversible modification of the substrate, the repair of apurinic sites through the base excision-repair pathway at a pharmacological concentration.