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Angiotensin II (AngII) regulates cerebral circulation and binds with a similar affinity to AT 1 and AT 2 receptors. Biased AT 1 agonists, such as TRV027, which are able to selectively activate β-arrestin while blocking the G q pathway, appear promising as new therapeutics. New pharmacological tools are needed to further explore the impact of biased AT 1 agonists on cells or tissues, such as the cerebral vessels. We designed and synthesized new fluorescent derivatives based on AngII, TRV027, or the AT 1 antagonist losartan. We conducted pharmacological characterization to determine their selectivity, potency, and ability to activate or not specific AT 1 transduction pathways in cells and cerebral arteries. We report the first highly AT 1 -selective fluorescent ligand, based on losartan, that retains its antagonist activity with high affinity. Fluorescent derivatives of TRV027 become AT 2 -selective and lose their AT 1 β-arrestin bias. These new ligands can be applied to trace AT 1 or AT 2 receptors in vitro and ex vivo.

Fluorogenic dimers with polarity-sensitive folding are powerful probes for live-cell bioimaging. They switch on their fluorescence only after interacting with their targets, thus leading to a high signal-to-noise ratio in wash-free bioimaging. We previously reported the first near-infrared fluorogenic dimers derived from cyanine 5.5 dyes for the optical detection of G protein-coupled receptors. Owing to their hydrophobic character, these dimers are prone to form nonspecific interactions with proteins such as albumin and with the lipid bilayer of the cell membrane resulting in a residual background fluorescence in complex biological media. Herein, we report the rational design of new fluorogenic dimers derived from cyanine 5. By modulating the chemical structure of the cyanine units, we discovered that the two asymmetric cyanine 5.25 dyes were able to form intramolecular H-aggregates and self-quenched in aqueous media. Moreover, the resulting original dimeric probes enabled a significant reduction of the nonspecific interactions with bovine serum albumin and lipid bilayers compared with the first generation of cyanine 5.5 dimers. Finally, the optimized asymmetric fluorogenic dimer was grafted to carbetocin for the specific imaging of the oxytocin receptor under no-wash conditions directly in cell culture media, notably improving the signal-to-background ratio compared with the previous generation of cyanine 5.5 dimers.

The pre-integration steps of the HIV-1 viral cycle are some of the most valuable targets of recent therapeutic innovations. HIV-1 integrase (IN) displays multiple functions, thanks to its considerable conformational flexibility. Recently, such flexible proteins have been characterized by their ability to form biomolecular condensates as a result of Liquid-Liquid-Phase-Separation (LLPS), allowing them to evolve in a restricted microenvironment within cells called membrane-less organelles (MLO). The LLPS context constitutes a more physiological approach to study the integration of molecular mechanisms performed by intasomes (complexes containing viral DNA, IN, and its cellular cofactor LEDGF/p75). We investigated here if such complexes can form LLPS in vitro and if IN enzymatic activities were affected by this LLPS environment. We observed that the LLPS formed by IN-LEDGF/p75 functional complexes modulate the in vitro IN activities. While the 3'-processing of viral DNA ends was drastically reduced inside LLPS, viral DNA strand transfer was strongly enhanced. These two catalytic IN activities appear thus tightly regulated by the environment encountered by intasomes., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

As in many other organisms, tRNA-derived RNAs (tDRs) exist in plants and likely have multiple functions. We previously showed that tDRs are present in Arabidopsis under normal growth conditions, and that the ones originating from alanine tRNAs are the most abundant in leaves. We also showed that tDRs Ala of 20 nt produced from mature tRNA Ala (AGC) can block in vitro protein translation. Here, we report that first, these tDRs Ala (AGC) can be found within peculiar foci in the cell that are neither P-bodies nor stress granules and, second, that they assemble into intermolecular RNA G-quadruplex (rG4) structures. Such tDR Ala rG4 structures can specifically interact with an Arabidopsis DEA(D/H) RNA helicase, the DExH1 protein, and unwind them. The rG4-DExH1 protein interaction relies on a glycine-arginine domain with RGG/RG/GR/GRR motifs present at the N-terminal extremity of the protein. Mutations on the four guanine residues located at the 5' extremity of the tDR Ala abolish its rG4 structure assembly, association with the DExH1 protein, and foci formation, but they do not prevent protein translation inhibition in vitro. Our data suggest that the sequestration of tDRs Ala into rG4 complexes might represent a way to modulate accessible and functional tDRs for translation inhibition within the plant cell via the activity of a specific RNA helicase, DExH1., (© 2023 The Authors. The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.)

Monosialoganglioside GM3 is the simplest ganglioside involved in various cellular signaling. Cell surface distribution of GM3 is thought to be crucial for the function of GM3, but little is known about the cell surface GM3 distribution. It was shown that anti-GM3 monoclonal antibody binds to GM3 in sparse but not in confluent melanoma cells. Our model membrane study evidenced that monoclonal anti-GM3 antibodies showed stronger binding when GM3 was in less fluid membrane environment. Studies using fluorescent GM3 analogs suggested that GM3 was clustered in less fluid membrane. Moreover, fluorescent lifetime measurement showed that cell surface of high density melanoma cells is more fluid than that of low density cells. Lipidomics and fatty acid supplementation experiment suggested that monounsaturated fatty acid-containing phosphatidylcholine contributed to the cell density-dependent membrane fluidity. Our results indicate that anti-GM3 antibody senses GM3 clustering and the number and/or size of GM3 cluster differ between sparse and confluent melanoma cells., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The Human Immunodeficiency Virus-1 (HIV-1) nucleocapsid protein (NC) as a mature protein or as a domain of the Gag precursor plays important roles in the early and late phases of the infection. To better understand its roles, we searched for new cellular partners and identified the RNA-binding protein Unr/CSDE1, Upstream of N-ras, whose interaction with Gag and NCp7 was confirmed by co-immunoprecipitation and FRET-FLIM. Unr interaction with Gag was found to be RNA-dependent and mediated by its NC domain. Using a dual luciferase assay, Unr was shown to act as an ITAF (IRES trans-acting factor), increasing the HIV-1 IRES-dependent translation. Point mutations of the HIV-1 IRES in a consensus Unr binding motif were found to alter both the IRES activity and its activation by Unr, suggesting a strong dependence of the IRES on Unr. Interestingly, Unr stimulatory effect is counteracted by NCp7, while Gag increases the Unr-promoted IRES activity, suggesting a differential Unr effect on the early and late phases of viral infection. Finally, knockdown of Unr in HeLa cells leads to a decrease in infection by a non-replicative lentivector, proving its functional implication in the early phase of viral infection.

Interconversions between nucleic acid structures play an important role in transcriptional and translational regulation and also in repair and recombination. These interconversions are frequently promoted by nucleic acid chaperone proteins. To monitor their kinetics, Förster resonance energy transfer (FRET) is widely exploited using ensemble fluorescence intensity measurements in pre-steady-state stopped-flow experiments. Such experiments only provide a weighted average of the emission of all species in solution and consume large quantities of materials. Herein, we lift these limitations by combining time-resolved fluorescence (TRF) with droplet microfluidics (DmF). We validate the innovative TRF-DmF approach by investigating the well characterized annealing of the HIV-1 (+)/(-) Primer Binding Sequences (PBS) promoted by a HIV-1 nucleocapsid peptide. Upon rapid mixing of the FRET-labelled (-)PBS with its complementary (+)PBS sequence inside microdroplets, the TRF-DmF set-up enables resolving the time evolution of sub-populations of reacting species and reveals an early intermediate with a ∼50 ps donor fluorescence lifetime never identified so far. TRF-DmF also favorably compares with single molecule experiments, as it offers an accurate control of concentrations with no upper limit, no need to graft one partner on a surface and no photobleaching issues., (© The Author(s) 2021. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Objectives: The objective of this study was to describe the characteristics of pediatric palliative care (PPC) patients presenting to a pediatric emergency department (ED) and these patients' ED visits., Methods: This retrospective chart review was conducted from April 1, 2007, to March 31, 2012, in a tertiary care pediatric university-affiliated hospital. Eligible patients had initial PPC consultations during the study period; all ED visits by these patients were included. Data were drawn from the ED's electronic data system and patient's medical chart., Results: A total of 290 new patients were followed by the PPC team, and 94 (32.4%) consulted the ED. Pediatric palliative care patients who consulted the ED had a median age of 7 years and baseline diagnoses of cancer (39.4%) or encephalopathy (27.7%). No patients died in the ED, but 36 (38.3%) died in hospital after an ED visit and 18 (19.1%) within 72 hours of admission. Pediatric palliative care patients consulted 219 times, with a median number of visits per patient of 2 (range, 1-8). They presented acutely ill as per triage scales. Reasons for consultation included respiratory distress/dyspnea (30.6%), pain (12.8%), seizure (11.4%), and fever (9.1%). Patients were often admitted to wards (61.2%) and the pediatric intensive care unit (7.3%). Two thirds (65.7%) of patients had signed an advanced care directive at the time of their visit. Discussions about goals of care occurred in 37.4% of visits., Conclusions: Pediatric palliative care patients present to the ED acutely ill, often at their end of life, and goals of care are not always discussed. This is a first step toward understanding how to improve PPC patients' ED care., Competing Interests: Disclosure: The authors declare no conflict of interest., (Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.)

The nucleocapsid (NC) protein plays key roles in Human Immunodeficiency Virus 1 (HIV-1) replication, notably by condensing and protecting the viral RNA genome and by chaperoning its reverse transcription into double-stranded DNA (dsDNA). Recent findings suggest that integration of viral dsDNA into the host genome, and hence productive infection, is linked to a small subpopulation of viral complexes where reverse transcription was completed within the intact capsid. Therefore, the synthesized dsDNA has to be tightly compacted, most likely by NC, to prevent breaking of the capsid in these complexes. To investigate NC's ability to compact viral dsDNA, we here characterize the compaction of single dsDNA molecules under unsaturated NC binding conditions using nanofluidic channels. Compaction is shown to result from accumulation of NC at one or few compaction sites, which leads to small dsDNA condensates. NC preferentially initiates compaction at flexible regions along the dsDNA, such as AT-rich regions and DNA ends. Upon further NC binding, these condensates develop into a globular state containing the whole dsDNA molecule. These findings support NC's role in viral dsDNA compaction within the mature HIV-1 capsid and suggest a possible scenario for the gradual dsDNA decondensation upon capsid uncoating and NC loss., (© The Author(s) 2021. Published by Oxford University Press on behalf of Nucleic Acids Research.)

The HIV-1 Gag protein playing a key role in HIV-1 viral assembly has recently been shown to interact through its nucleocapsid domain with the ribosomal protein L7 (RPL7) that acts as a cellular co-factor promoting Gag's nucleic acid (NA) chaperone activity. To further understand how the two proteins act together, we examined their mechanism individually and in concert to promote the annealing between dTAR, the DNA version of the viral transactivation element and its complementary cTAR sequence, taken as model HIV-1 sequences. Gag alone or complexed with RPL7 was found to act as a NA chaperone that destabilizes cTAR stem-loop and promotes its annealing with dTAR through the stem ends via a two-step pathway. In contrast, RPL7 alone acts as a NA annealer that through its NA aggregating properties promotes cTAR/dTAR annealing via two parallel pathways. Remarkably, in contrast to the isolated proteins, their complex promoted efficiently the annealing of cTAR with highly stable dTAR mutants. This was confirmed by the RPL7-promoted boost of the physiologically relevant Gag-chaperoned annealing of (+)PBS RNA to the highly stable tRNALys3 primer, favoring the notion that Gag recruits RPL7 to overcome major roadblocks in viral assembly., (© The Author(s) 2020. Published by Oxford University Press on behalf of Nucleic Acids Research.)

The nucleocapsid protein (NC) is a highly conserved protein that plays key roles in HIV-1 replication through its nucleic acid chaperone properties mediated by its two zinc fingers and basic residues. NC is a promising target for antiviral therapy, particularly to control viral strains resistant to currently available drugs. Since calixarenes with antiviral properties have been described, we explored the ability of calixarene hydroxymethylphosphonic or sulfonic acids to inhibit NC chaperone properties and exhibit antiviral activity. By using fluorescence-based assays, we selected four calixarenes inhibiting NC chaperone activity with submicromolar IC 50 values. These compounds were further shown by mass spectrometry, isothermal titration calorimetry, and fluorescence anisotropy to bind NC with no zinc ejection and to compete with nucleic acids for the binding to NC. Molecular dynamic simulations further indicated that these compounds interact via their phosphonate or sulfonate groups with the basic surface of NC but not with the hydrophobic plateau at the top of the folded fingers. Cellular studies showed that the most soluble compound CIP201 inhibited the infectivity of wild-type and drug-resistant HIV-1 strains at low micromolar concentrations, primarily targeting the early steps of HIV-1 replication. Moreover, CIP201 was also found to inhibit the flipping and polymerization activity of reverse transcriptase. Calixarenes thus form a class of noncovalent NC inhibitors, endowed with a new binding mode and multitarget antiviral activity.

The HIV-1 nucleocapsid protein 7 (NC) is a potential target for effective antiretroviral therapy due to its central role in virus replication, mainly linked to nucleic acid (NA) chaperone activity, and low susceptibility to drug resistance. By screening a compounds library, we identified the aminopyrrolic compound CN14_17, a known carbohydrate binding agent, that inhibits the NC chaperone activity in the low micromolar range. Different from most of available NC inhibitors, CN14_17 fully prevents the NC-induced annealing of complementary NA sequences. Using fluorescence assays and isothermal titration calorimetry, we found that CN14_17 competes with NC for the binding to NAs, preferentially targeting single-stranded sequences. Molecular dynamics simulations confirmed that binding to cTAR occurs preferably within the guanosine-rich single stranded sequence. Finally, CN14_17 exhibited antiretroviral activity in the low micromolar range, although with a moderate therapeutic index. Overall, CN14_17 might be the progenitor of a new promising class of NC inhibitors., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)

Ceramide phosphoethanolamine (CPE), a major sphingolipid in invertebrates, is crucial for axonal ensheathment in Drosophila. Darkfield microscopy revealed that an equimolar mixture of bovine buttermilk CPE (milk CPE) and 1,2-dioleoyl-sn-glycero-3-phosphocholine (diC18:1 PC) tends to form tubules and helical ribbons, while pure milk CPE mainly exhibits amorphous aggregates and, at low frequency, straight needles. Negative staining electron microscopy indicated that helices and tubules were composed of multilayered 5-10 nm thick slab-like structures. Using different molecular species of PC and CPE, we demonstrated that the acyl chain length of CPE but not of PC is crucial for the formation of tubules and helices in equimolar mixtures. Incubation of the lipid suspensions at the respective phase transition temperature of CPE facilitated the formation of both tubules and helices, suggesting a dynamic lipid rearrangement during formation. Substituting diC18:1 PC with diC18:1 PE or diC18:1 PS failed to form tubules and helices. As hydrated galactosylceramide (GalCer), a major lipid in mammalian myelin, has been reported to spontaneously form tubules and helices, it is believed that the ensheathment of axons in mammals and Drosophila is based on similar physical processes with different lipids.

Several children receiving palliative care experience dyspnea and pain. An order protocol for distress (OPD) is available at Sainte-Justine Hospital, aimed at alleviating respiratory distress, pain and anxiety in pediatric palliative care patients. This study evaluates the clinical use of the OPD at Sainte-Justine Hospital, through a retrospective chart review of all patients for whom the OPD was prescribed between September 2009 and September 2012. Effectiveness of the OPD was assessed using chart documentation of the patient's symptoms, or the modified Borg scale. Safety of the OPD was evaluated by measuring the time between administration of the first medication and the patient's death, and clinical evolution of the patient as recorded in the chart. One hundred and four (104) patients were included in the study. The OPD was administered at least once to 78 (75%) patients. A total of 350 episodes of administration occurred, mainly for respiratory distress (89%). Relief was provided in 90% of cases. The interval between administration of the first protocol and death was 17 h; the interval was longer in children with cancer compared to other illnesses ( p = 0.02). Data from this study support the effectiveness and safety of using an OPD for children receiving palliative care.

The nucleocapsid protein NC is a crucial component in the human immunodeficiency virus type 1 life cycle. It functions both in its processed mature form and as part of the polyprotein Gag that plays a key role in the formation of new viruses. NC can protect nucleic acids (NAs) from degradation by compacting them to a dense coil. Moreover, through its NA chaperone activity, NC can also promote the most stable conformation of NAs. Here, we explore the balance between these activities for NC and Gag by confining DNA-protein complexes in nanochannels. The chaperone activity is visualized as concatemerization and circularization of long DNA via annealing of short single-stranded DNA overhangs. The first ten amino acids of NC are important for the chaperone activity that is almost completely absent for Gag. Gag condenses DNA more efficiently than mature NC, suggesting that additional residues of Gag are involved. Importantly, this is the first single DNA molecule study of full-length Gag and we reveal important differences to the truncated Δ-p6 Gag that has been used before. In addition, the study also highlights how nanochannels can be used to study reactions on ends of long single DNA molecules, which is not trivial with competing single DNA molecule techniques.

The HIV Tat protein competes with the 7SK:HEXIM interaction to hijack pTEFb from 7SK snRNP and recruit it to the TAR motif on stalled viral transcripts. Here we solve structures of 7SK stemloop-1 and TAR in complex with Tat's RNA binding domain (RBD) to gain insights into this process. We find that 7SK is peppered with arginine sandwich motifs (ASM)-three classical and one with a pseudo configuration. Despite having similar RBDs, the presence of an additional arginine, R52, confers Tat the ability to remodel the pseudo configuration, required for HEXIM binding, into a classical sandwich, thus displacing HEXIM. Tat also uses R52 to remodel the TAR bulge into an ASM whose structure is identical to that of the remodeled ASM in 7SK. Together, our structures reveal a dual structural mimicry wherein viral Tat and TAR have co-opted structural motifs present in cellular HEXIM and 7SK for productive transcription of its genome.

Due to its essential roles in the viral replication cycle and to its highly conserved sequence, the nucleocapsid protein (NCp7) of the human immunodeficiency virus type 1 is a target of choice for inhibiting replication of the virus. Most NCp7 inhibitors identified so far are small molecules. A small number of short peptides also act as NCp7 inhibitors by competing with its nucleic acid (NA) binding and chaperone activities but exhibit antiviral activity only at relatively high concentrations. In this work, in order to obtain more potent NCp7 competitors, we designed a library of longer peptides (10-17 amino acids) whose sequences include most of the NCp7 structural determinants responsible for its specific NA binding and destabilizing activities. Using an in vitro assay, the most active peptide (pE) was found to inhibit the NCp7 destabilizing activity, with a 50% inhibitory concentration in the nanomolar range, by competing with NCp7 for binding to its NA substrates. Formulated with a cell-penetrating peptide (CPP), pE was found to accumulate into HeLa cells, with low cytotoxicity. However, either formulated with a CPP or overexpressed in cells, pE did not show any antiviral activity. In vitro competition experiments revealed that its poor antiviral activity may be partly due to its sequestration by cellular RNAs. The selected peptide pE therefore appears to be a useful tool for investigating NCp7 properties and functions in vitro, but further work will be needed to design pE-derived peptides with antiviral activity.

Background: It is known that information regarding the quality of life of a patient is central to pediatric palliative care. This information allows professionals to adapt the care and support provided to children and their families. Previous studies have documented the major areas to be investigated in order to assess the quality of life, although it is not yet known what operational criteria or piece of information should be used in the context of pediatric palliative care. The present study aims to: 1) Identify signs of quality of life and evaluation methods currently used by professionals to assess the quality of life of children with cancer receiving palliative care. 2) Collect recommendations from professionals to improve the evaluation of quality of life in this context., Methods: We selected a qualitative research design and applied an inductive thematic content analysis to the verbal material. Participants included 20 members of the Department of Hematology-Oncology at CHU Sainte-Justine from various professions (e.g. physicians, nurses, psychosocial staff) who had cared for at least one child with cancer receiving palliative care in the last year., Results: Professionals did not have access to pre-established criteria or to a defined procedure to assess the quality of life of children they followed in the context of PPC. They reported basing their assessment on the child's non-verbal cues, relational availability and elements of his/her environment. These cues are typically collected through observation, interpretation and by asking the child, his/her parents, and other members of the care. To improve the assessment of quality of life professionals recommended optimizing interdisciplinary communication, involving the child and the family in the evaluation process, increasing training to palliative care in hematology/oncology, and developing formalized measurement tools., Conclusion: The formulation of explicit criteria to assess the quality of life in this context, along with detailed recommendations provided by professionals, support the development of systematic measurement strategy. Such a strategy would contribute to the development of common care goals and further facilitate communication between professionals and with the family.

Introduction: Pediatric surgeons are often involved in the management of severely or terminally ill patients. However, articles addressing their specific roles in the context of palliative care are almost inexistent. We sought to characterize the involvement of pediatric surgeons caring for children near end of life., Methods: Chart review of children who had a procedure under general anesthesia within 6months of their death over a five-year period at a tertiary children's hospital (excluding traumas and neonatology cases). In addition to demographic and clinical data, we recorded the aim of the procedures performed, the involvement of the palliative care service, and presence of DNAR orders., Results: The analysis included 83 patients (mean age: 8years). Forty-four children had more than one procedure (range 2-10). Pediatric palliative care service was involved in 66 cases (80%). A majority of patients had cancer (50%), and the most frequent cause of death was oncologic progression (46%). Ten patients died of a complication following their intervention. The aim of the procedure was palliative in 48 cases (29 for symptoms control and 19 to facilitate care), diagnostic in 16, and curative in 19. Forty-five procedures were performed urgently and 14 despite DNAR orders., Conclusion: Surgeon involvement with children near end of life is not infrequent. The procedures performed are varied and can be categorized according to their aim. Lack of formal palliative care training by surgeons highlights the need for increased collaboration with palliative care services to provide children optimal care when they need it most., Level of Evidence: IV., (Copyright © 2018. Published by Elsevier Inc.)

Aims: This study explored how paediatric healthcare professionals experienced and coped with end-of-life conflicts and identified how to improve coping strategies., Methods: A questionnaire was distributed to all 2300 professionals at a paediatric university hospital, covering the frequency of end-of-life conflicts, participants, contributing factors, resolution strategies, outcomes and the usefulness of specific institutional coping strategies., Results: Of the 946 professionals (41%) who responded, 466 had witnessed or participated in paediatric end-of-life discussions: 73% said these had led to conflict, more frequently between professionals (58%) than between professionals and parents (33%). Frequent factors included professionals' rotations, unprepared parents, emotional load, unrealistic parental expectations, differences in values and beliefs, parents' fear of hastening death, precipitated situations and uncertain prognosis. Discussions with patients and parents and between professionals were the most frequently used coping strategies. Conflicts were frequently resolved by the time of death. Professionals mainly supported designating one principal physician and nurse for each patient, two-step interdisciplinary meetings - between professionals then with parents - postdeath ethics meetings, bereavement follow-up protocols and early consultations with paediatric palliative care and clinical ethics services., Conclusion: End-of-life conflicts were frequent and predominantly occurred between healthcare professionals. Specific interventions could target most of the contributing factors., (©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.)

HIV/AIDS is still one of the leading causes of death worldwide. Current drugs that target the canonical steps of the HIV-1 life cycle are efficient in blocking viral replication but are unable to eradicate HIV-1 from infected patients. Moreover, drug resistance (DR) is often associated with the clinical use of these molecules, thus raising the need for novel drug candidates as well as novel putative drug targets. In this respect, pharmacological inhibition of the highly conserved and multifunctional nucleocapsid protein (NC) of HIV-1 is considered a promising alternative to current drugs, particularly to overcome DR. Here, using a multidisciplinary approach combining in silico screening, fluorescence-based molecular assays, and cellular antiviral assays, we identified nordihydroguaiaretic acid (6), as a novel natural product inhibitor of NC. By using NMR, mass spectrometry, fluorescence spectroscopy, and molecular modeling, 6 was found to act through a dual mechanism of action never highlighted before for NC inhibitors (NCIs). First, the molecule recognizes and binds NC noncovalently, which results in the inhibition of the nucleic acid chaperone properties of NC. In a second step, chemical oxidation of 6 induces a potent chemical inactivation of the protein. Overall, 6 inhibits NC and the replication of wild-type and drug-resistant HIV-1 strains in the low micromolar range with moderate cytotoxicity that makes it a profitable tool compound as well as a good starting point for the development of pharmacologically relevant NCIs.

Objective: The goal of pediatric palliative care (PPC) is to maintain the quality of life (QoL) of children whose lives are threatened. However, there are sparse scientific data on the domains of QoL in this particular context, and no measurement strategies are available. The present study aims to describe the domains of QoL in the context of PPC in oncology, according to the perceptions of professional caregivers., Method: Semistructured interviews were conducted with a random sample of 20 professional caregivers from the Division of Hematology/Oncology at Le Centre Hospitalier Universitaire Sainte-Justine (Montréal, Canada). The caregivers were asked about their perceptions about the QoL of the children they have cared for in this context. The data were analyzed using inductive thematic content analysis., Results: The analysis allowed us to identify seven domains of QoL: "physical comfort," "alleviation of psychological suffering," "fun and the present moment," "sense of control," "feeling valued and appreciated," "feeling that life goes on," and "meaningful social relationships.", Significance of Results: Caregivers recount the regard that should be accorded to maintaining well-being and a sense of fun, as well as fostering the child's abilities, taking account of the progression of the disease, and to fulfilling his or her needs, especially social ones. Our results also demonstrate that all domains were positively referred to by professional caregivers. The data from our study will lead to better assessment of QoL according to the trajectory of a child with advanced cancer while undergoing PPC.

A series of 26 3-hydroxychromones, three bis-flavonols and four 3-hydroxyquinolones were studied to evaluate their fluorescence response to interaction with ATP in buffer. The dyes differ by the total charge, the size and number of their aromatic units, as well as the position or electron-donating ability of their substituents. All of them were suggested to form complexes with ATP of 1:1 and 1:2 stoichiometry, which can be evidenced by their bright fluorescence and their 3000-6000 cm -1 red-shifted excitation band. These fluorescent complexes allow detection of ATP concentrations over 3 orders of magnitude, whereas most other known probes cover no more than two orders. In total, the dyes allow ATP detection from 0.001 to 57 mm. In addition, most of the dye-ATP complexes can be excited in the visible and monitored in the red region of the spectrum. The response amplitude of the described dyes to ATP is as high as for the best known probes. Considering that complexation takes place at neutral pH, the studied dyes form a toolbox of fluorescent probes for intensiometric and ratiometric measurements of ATP concentration in a broad concentration range. Finally, the obtained results stimulate the idea that most of natural 3-hydroxyflavones in living cells may form complexes with ATP., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Our objective was to develop a rich description of how parents experience their grief in the first year after the death of their child, and how various bereavement follow-up and support services helped them during this time, with the aim of informing follow-up and support services offered to bereaved parents. Our findings situated parents' individual experiences of coping within the social and institutional contexts in which they grieved. In the first year after the death of their child, parents regulated their intense feelings of grief through loss-oriented, restoration-oriented, and/or meaning reconstruction strategies. Often, parents' relationships with others and many of the bereavement follow-up and support services helped them in this regard. This article also explores how the results may aid service providers in accompanying parents in a way that optimizes outcomes for these parents.

In this work, we used firefly oxyluciferin (OxyLH 2 ) and its polarity-dependent fluorescence mechanism as a sensitive tool to monitor biomolecular interactions. The chromophores, OxyLH 2 , and its two analogues, 4-MeOxyLH and 4,6'-DMeOxyL, were modified trough carboxylic functionalization and then coupled to the N-terminus part of Tat and NCp7 peptides of human immunodeficiency virus type-1 (HIV-1). The photophysical properties of the labeled peptides were studied in live cells as well as in complex with different oligonucleotides in solution. By monitoring the emission properties of these derivatives we were able, for the first time, to study in vitro biomolecular interactions using oxyluciferin as a sensor. As an additional application, cyclopropyl-oxyluciferin (5,5-Cpr-OxyLH) was site-specifically conjugated to the thiol group (Cys-232) of the human protein α-1 antytripsin to investigate its interaction with porcine pancreatic elastase. Our data demonstrate that OxyLH 2 and its derivatives can be used as fluorescence reporters for monitoring biomolecular interactions.

Although the enzyme-linked immunosorbent assay (ELISA) is well established for quantitating epitopes on inactivated virions used as vaccines, it is less suited for detecting potential overlaps between the epitopes recognized by different antibodies raised against the virions. We used fluorescent correlation spectroscopy (FCS) to detect the potential overlaps between 3 monoclonal antibodies (mAbs 4B7-1H8-2E10, 1E3-3G4, 4H8-3A12-2D3) selected for their ability to specifically recognize poliovirus type 3. Competition of the Alexa488-labeled mAbs with non-labeled mAbs revealed that mAbs 4B7-1H8-2E10 and 4H8-3A12-2D3 compete strongly for their binding sites on the virions, suggesting an important overlap of their epitopes. This was confirmed by the cryo-electron microscopy (cryo EM) structure of the poliovirus type 3 complexed with the corresponding antigen-binding fragments (Fabs) of the mAbs, which revealed that Fabs 4B7-1H8-2E10 and 4H8-3A12-2D3 epitopes share common amino acids. In contrast, a less efficient competition between mAb 1E3-3G4 and mAb 4H8-3A12-2D3 was observed by FCS, and there was no competition between mAbs 1E3-3G4 and 4B7-1H8-2E10. The Fab 1E3-3G4 epitope was found by cryoEM to be close to but distinct from the epitopes of both Fabs 4H8-3A12-2D3 and 4B7-1H8-2E10. Therefore, the FCS data additionally suggest that mAbs 4H8-3A12-2D3 and 4B7-1H8-2E10 bind in a different orientation to their epitopes, so that only the former sterically clashes with the mAb 1E3-3G4 bound to its epitope. Our results demonstrate that FCS can be a highly sensitive and useful tool for assessing the potential overlap of mAbs on viral particles.

We report herein the highly diastereoselective synthesis of octahedral cationic Ir(iii) hydride complexes with a stereogenic metal centre following various strategies. The configurational stability of these compounds has also been investigated.

Background: An order protocol for distress (OPD), including respiratory distress and acute pain crisis, has been established for pediatric palliative care patients at Sainte-Justine Hospital (SJH). After discussion with the patient/his or her family, the OPD is prescribed by the attending physician whenever judged appropriate. The OPD can then be initiated by the bedside nurse when necessary; the physician is notified after the first dose is administered., Objectives: The study objectives were to evaluate the perceptions and experience of the medical/nursing staff towards the use of the OPD., Methods: A survey was distributed to all physicians/nurses working on wards with pediatric palliative care patients. Answers to the survey were anonymous, done on a voluntary basis, and after consent of the participant., Results: Surveys (258/548) were answered corresponding to a response rate of 47%. According to the respondents, the most important motivations in using the OPD were the desire to relieve patient's distress and the speed of relief of distress by the OPD; the most important obstacles were going against the patient's/his or her family's wishes and fear of hastening death. The respondents reported that the OPD was frequently (56%) or always (36%) effective in relieving the patient's distress. The respondents felt sometimes (16%), frequently (34%), or always (41%) comfortable in giving the OPD. They thought the OPD could never (12%), rarely (32%), sometimes (46%), frequently (8%), or always (1%) hasten death. Physicians were less favorable than nurses with the autonomy of bedside nurses to initiate the OPD before notifying the physician (p = 0.04). Overall, 95% of respondents considered that they would use the OPD in the future., Conclusions: Data from this survey shows that respondents are in favor of using the OPD at SJH and find it effective. Further training as well as support for health care professionals are mandatory in such palliative care settings.

Herein, we develop a convenient method to facilitate the solution-phase fluorescent labelling of peptides based on the chemoselective acylation of α-hydrazinopeptides. This approach combines the advantages of using commercially available amine-reactive dyes and very mild conditions, which are fully compatible with the chemical sensitivity of the dyes. The usefulness of this approach was demonstrated by the labelling of apelin-13 peptide. Various fluorescent probes were readily synthesized, enabling the rapid optimization of their affinities for the apelin receptor. Thus, the first far-red fluorescent ligand with sub-nanomolar affinity for the apelin receptor was characterized and shown to track the receptor efficiently in living cells by fluorescence confocal microscopy., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)