43 research outputs found
Disparate effects of chronic and acute theophylline on cyclosporine A nephrotoxicity
Abstract : We previously developed a model of acute cyclosporine A (CsA)-induced vasomotor nephrotoxicity in rabbits. As exogenous adenosine infusion mimics the haemodynamic changes that characterize acute renal failure (ARF), we wanted to know whether adenosine was a mediator in this model and whether an adenosine receptor blocker could prevent the CsA-induced ARF. Group 1 were untreated controls. Group 2 received CsA (25 mg/kg per day) for 5 days. Renal function parameters were measured, showing ARF in all animals compared to controls. Theophylline (1 mg/kg i.v. bolus) was then administered and renal function was reassessed. Theophylline significantly reduced renal vascular resistance (-8%) and increased renal blood flow (RBF) (+20%), glomerular filtration rate (GFR) (+50%), filtration fraction (+24%) and diuresis (+73%), suggesting that adenosine was involved in the CsA-induced ARF. In group 3, theophylline (30 mg/kg per day) was given concomitantly with CsA for 5 days. GFR was normalized, but theophylline did not hinder the drop in RBF seen with CsA alone in group 2. Microscopy observation of the kidneys showed that chronic theophylline administration aggravated the morphological changes induced by CsA alone. We conclude that CsA administration for 5 days induced a vasomotor nephropathy with an adenosine-mediated afferent arteriolar constriction which cannot be prevented by concomitant theophylline administratio
Multifunctional Glycoconjugates for Recruiting Natural Antibodies against Cancer Cells
Invited for the cover of this issue is Olivier Renaudet and co-workers at the Université Grenoble Alpes and funded by the European Research Council (CoG “LEGO′” no. 647938). The image illustrates a synthetic chemist playing with supramolecular structures to kill cancer cells by using natural antibodies present in the blood stream. Read the full text of the article at 10.1002/chem.201903327
Bronchiolitis: an update on management and prophylaxis.
Bronchiolitis is an acute respiratory illness that is the leading cause of hospitalization in young children less than 2 years of age in the UK. Respiratory syncytial virus is the most common virus associated with bronchiolitis and has the highest disease severity, mortality and cost. Bronchiolitis is generally a self-limiting condition, but can have serious consequences in infants who are very young, premature, or have underlying comorbidities. Management of bronchiolitis in the UK is guided by the National Institute for Health and Care Excellence (2015) guidance. The mainstays of management are largely supportive, consisting of fluid management and respiratory support. Pharmacological interventions including nebulized bronchodilators, steroids and antibiotics generally have limited or no evidence of efficacy and are not advised by National Institute of Health and Care Excellence. Antiviral therapeutics remain in development. As treatments are limited, there have been extensive efforts to develop vaccines, mainly targeting respiratory syncytial virus. At present, the only licensed product is a monoclonal antibody for passive immunisation. Its cost restricts its use to those at highest risk. Vaccines for active immunisation of pregnant women and young infants are also being developed
Structural influence of antibody recruiting glycodendrimers (ARGs) on antitumoral cytotoxicity
The recruitment of endogenous antibodies against cancer cells has become a reliable antitumoral immunotherapeutic alternative over the last decade. The covalent attachment of antibody and tumor binding modules (ABM and TBM) within a single, well-defined synthetic molecule was indeed demonstrated to promote the formation of an interacting ternary complex between both the antibodies and the targeted cell, which usually results in the simultaneous immune-mediated cellular destruction. In a preliminary study, we have described the first Antibody Recruiting Glycodendrimers (ARGs), combining cRGD as ligands for the αVβ3-expressing melanoma cell line M21 and Rha as ligand for natural IgM, and demonstrated that multivalency is an essential requirement to form this complex. In the present study, we synthesized a new series of ARGs composed of ABMs, i.e. self-condensed rhamnosylated cyclopeptide and polylysine dendrimer, which have been conjugated to the TBM with or without spacer. Flow cytometry and confocal microscopy experiments with human serum and different cell lines revealed that the ABM geometry significantly influences the ternary complex formation in M21, whereas no significant binding occurs in BT 549 having low integrin expression. In addition, we demonstrate with a cellular viability assay that ARGs induce high level of cytotoxicity against M21 which is also in close correlation with the ABM structure. In particular, we have shown that ARG combining cyclopeptide core and branches, with or without spacer, induce 40-57% of selective cytotoxicity against M21 cells in the presence of human serum as the unique source of immunity effectors. Finally, we also highlight that the spacer between ABM and TBM enables an increase of the immune-mediate cytotoxicity even with ABM of lower valency
Experiences of parents and caregivers in pediatric intensive care units: A qualitative study
International audienceBACKGROUND: In pediatric intensive care units (PICUs), parents and healthcare professionals attend to children who verbally and non-verbally express their pain and suffering, fears, anxieties, desires, and wishes in complex intensive care situations. What can we learn from these experiences to improve the way we can take care of and support children? OBJECTIVES: The main objective of this clinical ethics study was to focus on the experience stories of parents during their child’s hospitalization in a PICU, to analyze their discourse, and to propose an ethical perspective. METHOD: The current research collects the experience reports of parents during their child’s hospitalization in a PICU and those of the caregivers who treated them. A total of 17 semi-directive interviews were conducted in the PICU of the Nantes University Hospital from November 2017 to June 2019. Each interview lasted around 1 h. The main results of our study are analyzed and informed by the four ethical principles of T. Beauchamp and J. Childress: autonomy, beneficence, non-maleficence, and justice. RESULTS: The interviews highlighted the difficulties encountered by parents during the hospitalization of their children, such as the distance between their home and the hospital, the technicality of PICU environment, and the difficulty in finding their place as parents. For medical and paramedical teams, their main concerns are undoubtedly to improve the coherence and continuity of their stand toward parents, to promote parental autonomy, and to remain fully aware of the profound existential changes that the child’s illness brings about for parents: It is the caregivers’ duty to take this into account and to respect the parents’ rhythm as much as possible. CONCLUSIONS: The main disagreements between healthcare teams and parents, where they exist, are communication problems that are easily controlled, for the most part, by caregivers
Extracorporeal life support for patients with acute respiratory distress syndrome: report of a Consensus Conference
International audienceThe influenza H1N1 epidemics in 2009 led a substantial number of people to develop severe acute respiratory distress syndrome and refractory hypoxemia. In these patients, extracorporeal membrane oxygenation was used as rescue oxygenation therapy. Several randomized clinical trials and observational studies suggested that extracorporeal membrane oxygenation associated with protective mechanical ventilation could improve outcome, but its efficacy remains uncertain. Organized by the Societe de Reanimation de Langue Francaise (SRLF) in conjunction with the Societe Francaise d'Anesthesie et de Reanimation (SFAR), the Societe de Pneumologie de Langue Francaise (SPLF), the Groupe Francophone de Reanimation et d'Urgences Pediatriques (GFRUP), the Societe Francaise de Perfusion (SOFRAPERF), the Societe Francaise de Chirurgie Thoracique et Cardiovasculaire (SFCTV) et the Sociedad Espanola de Medecina Intensiva Critica y Unidades Coronarias (SEMICYUC), a Consensus Conference was held in December 2013 and a jury of 13 members wrote 65 recommendations to answer the five following questions regarding the place of extracorporeal life support for patients with acute respiratory distress syndrome: 1) What are the available techniques?; 2) Which patients could benefit from extracorporeal life support?; 3) How to perform extracorporeal life support?; 4) How and when to stop extracorporeal life support?; 5) Which organization should be recommended? To write the recommendations, evidence-based medicine (GRADE method), expert panel opinions, and shared decisions taken by all the thirteen members of the jury of the Consensus Conference were taken into account