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During neuronal development, the formation of neural circuits requires developing axons to traverse a diverse cellular and molecular environment to establish synaptic contacts with the appropriate postsynaptic partners. Essential to this process is the ability of developing axons to navigate guidance molecules presented by specialized populations of cells. These cells partition the distance traveled by growing axons into shorter intervals by serving as intermediate targets, orchestrating the arrival and departure of axons by providing attractive and repulsive guidance cues. The floor plate in the central nervous system (CNS) is a critical intermediate target during neuronal development, required for the extension of commissural axons across the ventral midline. In this review, we begin by giving a historical overview of the ventral commissure and the evolutionary purpose of decussation. We then review the axon guidance studies that have revealed a diverse assortment of midline guidance cues, as well as genetic and molecular regulatory mechanisms required for coordinating the commissural axon response to these cues. Finally, we examine the contribution of dysfunctional axon guidance to neurological diseases.

The knowledge and attitudes of health professionals towards older adults can have a significant impact on quality of health care. This study compared the knowledge of aging and attitudes towards older people held by students entering nursing, occupational therapy and physiotherapy education. Participants (n = 213) completed a question naire that consisted of the Kogan Scale concerning attitudes towards older people, Palmore's Facts on Aging Quiz Version 1 along with questions concerning social interaction with older people and demographic information. There were no differences in attitudinal scores or knowledge across the three student groups. This finding also held after controlling for age, gender, and prior work experience with older people. Analysis of the total sample in relation to the effect of social contact and age on knowledge and attitudes, indicated that those having more than monthly contact with older people had significantly less negative bias and less overall bias on the Facts on Aging Quiz. Similarly students 25 years and older had significantly higher attitudinal scores and greater positive bias on the Facts on Aging Quiz. An emphasis on innovative learning experiences that are introduced early in academic programmes may influence students' understanding, thinking, and attitudes towards older adults, so they are better prepared to meet the health care needs of this population. [ABSTRACT FROM AUTHOR]

Negative attitudes towards aging can be a substantial obstacle to the delivery of quality health care to older adults. This study compared the attitudes towards older people and knowledge of aging held by clinical educators and students in physiotherapy and occupational therapy. Participants (n=175) completed a questionnaire that consisted of the Kogan scale concerning attitudes towards older people, Palmore's Facts of Aging Quiz version 1, and questions concerning social interaction with older people and demographic information. The clinical educators of both professional groups had significantly higher attitudinal scores than the student participants in this study. After controlling for the effect of age, clinical educators had a significantly lower negative bias on the Facts of Aging Quiz than the students. Significantly higher positive bias scores on the FAQI were reported by the occupational therapy students and clinical educators in comparison to their physiotherapy counterparts. A stronger curriculum emphasis throughout the academic programme together with increased clinical placements in settings providing care for older people may be necessary to better equip students for the workplace. [ABSTRACT FROM AUTHOR]

Neonatal stroke may occur silently. Identification of potential embolic pathways unique to the neonate is important when investigating the aetiology of infarction and arterial occlusion, and preventing further episodes. This is a case report of an infant with venous thrombus embolising across the foramen ovale causing cerebral infarction and subclavian artery steal syndrome, without neurological signs. [ABSTRACT FROM AUTHOR]

We have identified an unexpected role for netrin1, a canonical axonal guidance cue, as a suppressor of bone morphogenetic protein (Bmp) signaling in the developing dorsal spinal cord. Using a combination of gain- and loss-of-function approaches in chicken and mouse embryonic models, as well as mouse embryonic stem cells (mESCs), we have observed that manipulating the level of netrin1 specifically alters the patterning of the Bmp-dependent dorsal interneurons (dIs), dI1-dI3. Altered netrin1 levels also change Bmp signaling activity, as assessed using bioinformatic approaches, as well as monitoring phosophoSmad1/5/8 activation, the canonical intermediate of Bmp signaling, and Id levels, a known Bmp target. Together, these studies support the hypothesis that netrin1 acts from the intermediate spinal cord to regionally confine Bmp signaling to the dorsal spinal cord. Thus, netrin1 has reiterative activities shaping dorsal spinal circuits, first by regulating cell fate decisions and then acting as a guidance cue to direct axon extension., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Reversible anion binding to lanthanide complexes in aqueous solution has emerged as an effective method for anion sensing. Through careful design of the organic ligand, luminescent lanthanide complexes capable of binding biologically relevant anions in a bidentate or monodentate manner can be realized. While single-crystal X-ray diffraction analyses and NMR spectroscopy have revealed the structural geometry of several host-guest complexes, the challenge remains in designing preorganized lanthanide receptors with enhanced anion selectivity for broader applications in diagnostics and bioimaging. To address this challenge, innovative and complementary methods to investigate host-anion binding geometry are becoming increasingly important. Herein, we demonstrate the combined use of Eu L 3 -edge extended X-ray absorption fine structure (EXAFS) and electron paramagnetic resonance (EPR) spectroscopy to elucidate the binding of nucleoside phosphates (ATP, ADP, and AMP) to a cationic lanthanide complex. We establish that ATP unequivocally binds the lanthanide center in a bidentate manner in water, while ADP adopts both bidentate and monodentate modes, and AMP binds in a monodentate manner. This interdisciplinary approach provides deeper insight into lanthanide host-guest chemistry in solution, laying the groundwork for designing emissive probes that undergo specific anion-induced structural changes and elicit desired optical responses upon binding.

Pseudocontact shifts (PCS) generated by paramagnetic lanthanide ions deliver powerful restraints for protein structure analysis by NMR spectroscopy. We present a new lanthanide tag that generates different PCSs than that of a related tag, which differs in structure by a single oxygen atom. It is highly reactive towards cysteine and performs well in turn-on luminescence and in EPR spectroscopy.

Dorsal interneurons (dIs) in the spinal cord encode the perception of touch, pain, heat, itchiness and proprioception. Previous studies using genetic strategies in animal models have revealed important insights into dI development, but the molecular details of how dIs arise as distinct populations of neurons remain incomplete. We have developed a resource to investigate dI fate specification by combining a single-cell RNA-Seq atlas of mouse embryonic stem cell-derived dIs with pseudotime analyses. To validate this in silico resource as a useful tool, we used it to first identify genes that are candidates for directing the transition states that lead to distinct dI lineage trajectories, and then validated them using in situ hybridization analyses in the developing mouse spinal cord in vivo. We have also identified an endpoint of the dI5 lineage trajectory and found that dIs become more transcriptionally homogeneous during terminal differentiation. This study introduces a valuable tool for further discovery about the timing of gene expression during dI differentiation and demonstrates its utility in clarifying dI lineage relationships., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2024. Published by The Company of Biologists Ltd.)

We report a new method to generate ion-responsive luminescent hydrogels, involving encapsulation of a luminescent lanthanide probe within crosslinked amphiphilic polymer particles and subsequent entrapment within a hydrogel. The resulting hydrogels are capable of reversible bicarbonate sensing, exhibit no leaching, and can be tuned for a range of sensing applications.

To evaluate the impact of participant-selected music listening as an adjunct to pulmonary rehabilitation (PR) in people with COPD. Adults with COPD referred to PR were randomly assigned to participant-selected music listening (intervention group, [IG]) or usual care (control group [CG]) during an 8-weeks PR program. Prior to training, the IG completed an interview with a registered music therapist to identify music preferences. IG participants listened to an individualised playlist; CG participants had usual care. Primary outcomes included end-6-min walk test symptoms (dyspnoea and exertion) and dyspnoea (Multidimensional Dyspnoea Profile [MDP]), measured pre and post PR and 6-months follow-up. 58 participants, FEV1 52.4 (25.9)% pd) were recruited. There were no between-group differences following the intervention ( p > .05 for all outcomes at all time points). Within-group differences following PR were significant for MDP sensory quality: IG mean difference [95% CI] -2.2 [-3.3 to -1.2]; CG -1.5 [-2.5 to -0.5] points; MDP emotional response: IG -3.2 [-4.2 to -2.3]; CG -2.2 [-3.2 to -1.3] points). Participant-selected music listening during PR offered no greater benefit to symptoms of dyspnoea or exertion compared to usual care. With the study limited by COVID-19 restrictions, the role of this adjunct remains to be clarified., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Context: Lung cancer patients with chronic obstructive pulmonary disease (COPD) may have greater palliative care needs due to poor prognosis and symptom burden., Objectives: We sought to compare the provision of timely palliative care and symptom burden by COPD status., Methods: We performed a retrospective, population-based cohort study of individuals diagnosed with lung cancer in Ontario, Canada (2009-2019) using health administrative databases and cancer registries. The impact of COPD on the probability of receiving palliative care was determined accounting for dying as a competing event, overall and stratified by stage. The provision of palliative care for patients with severe symptoms (Edmonton Symptom Assessment Scale score ≥ 7), location of the first palliative care visit and symptom severity were compared by COPD status., Results: A total of 74,993 patients were included in the study (48% of patients had available symptom data). At the time of lung cancer diagnosis, 50% of patients had COPD. Stage I-III patients with COPD were more likely to receive palliative care (adjusted Hazard Ratio (HR)s: 1.05-1.31) with no difference for stage IV (1.02, 95% CI: 1.00-1.04). Despite having severe symptoms, very few patients with early-stage disease received palliative care (Stage I: COPD-23% vs. no COPD-18%, SMD = 0.12). Most patients (84%) reported severe symptoms and COPD worsened symptom burden, especially among early-stage patients., Conclusion: COPD impacts the receipt of palliative care and symptom burden for patients with early-stage lung cancer. Many patients with severe symptoms did not receive palliative care, suggesting unmet needs among this vulnerable population., (Copyright © 2023 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.)

Background: Chronic obstructive pulmonary disease (COPD) and lung cancer commonly coexist and have significant symptom overlap. We sought to compare the symptom burden of lung cancer patients with COPD to those without COPD., Methods: We conducted a retrospective, cross-sectional study of stage I-IV lung cancer patients in Ontario, Canada, who completed the Edmonton Symptom Assessment Scale (ESAS) within 90 days of diagnosis. COPD was ascertained using a validated algorithm and patients were grouped as: no COPD, previously diagnosed COPD (at least 90 days prior to lung cancer diagnosis), and newly diagnosed COPD (within 90 days of lung cancer diagnosis). The association between COPD status and any moderate to severe symptom (ESAS ≥4) and the number of moderate to severe symptoms was determined using multivariable modified Poisson regression analyses. Multivariable linear regression analysis was used to compare total symptom distress scores. Analyses were stratified by limited (I/II) and advanced stage (III/IV)., Results: Among 38,898 lung cancer patients, 53% had COPD (previously diagnosed 43%, newly diagnosed 10%). Collectively, those with previously diagnosed COPD had the most severe symptom burden. Across all stages, both COPD groups had a significantly higher risk of experiencing any (relative risk: 1.04 to 1.18) and multiple moderate to severe symptoms (RR 1.05 to 1.24), in addition to higher total symptom distress scores (P<0.0001). Differences in symptom burden between groups were most pronounced among early-stage patients., Conclusions: Lung cancer patients with underlying COPD have worse symptom burden, indicating a need for interventions that effectively alleviate symptoms., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-23-560/coif). S.J.B. and A.S.G. report that this study received Godfrey S. Pettit Block Term Grant from the Division of Respirology at the University of Toronto. S.J.B. received stipend support from the Canadian Institutes of Health Research. A.V.L. has received speaker fees from AstraZeneca and is a member of the advisory board, and has received clinician-scientist funding from the MOH via the Ontario Association of Radiation Oncologists. A.V.L. serves as an unpaid editorial board member of Translational Lung Cancer Research from November 2022 to October 2024. L.P. has received clinician-scientist funding from the MOH via the Ontario Association of Radiation Oncologists. A.S.G. has received funding support from the Government of Ontario and the PSI Foundation. The other authors have no conflicts of interest to declare., (2023 Translational Lung Cancer Research. All rights reserved.)

Synthetic anion receptors are increasingly being explored for the transport of anions across lipid membranes because of their potential therapeutic applications. A considerable amount of research focuses on the transport of chloride, whereas the transmembrane transport of inorganic phosphate has not been reported to date, despite the biological relevance of this anion. Here we present a calix[4]pyrrole with a bisurea strap that functions as a receptor and transporter for H 2 PO 4 - , relying on the formation of eight hydrogen bonds and efficient encapsulation of the anion. Using a phosphate-sensitive lanthanide probe and 31 P NMR spectroscopy, we demonstrate that this receptor can transport phosphate into vesicles by H 2 PO 4 - /Cl - antiport, H 2 PO 4 - uniport, and Cs + /H 2 PO 4 - symport mechanisms. This first example of inorganic phosphate transport by a neutral receptor opens perspectives for the future development of transporters for various biological phosphates.

Chronic obstructive pulmonary disease (COPD) is associated with an increased risk of lung cancer; however, the association between COPD and stage of lung cancer diagnosis is unclear. We conducted a population-based cross-sectional analysis of lung cancer patients (2008-2020) in Ontario, Canada. Using estimated propensity scores and inverse probability weighting, logistic regression models were developed to assess the association between COPD and lung cancer stage at diagnosis (early: I/II, advanced: III/IV), accounting for prior chest imaging. We further examined associations in subgroups with previously diagnosed and undiagnosed COPD. Over half (55%) of all lung cancer patients in Ontario had coexisting COPD (previously diagnosed: 45%, undiagnosed at time of cancer diagnosis: 10%). Compared to people without COPD, people with COPD had 30% lower odds of being diagnosed with lung cancer in the advanced stages (OR = 0.70, 95% CI: 0.68 to 0.72). Prior chest imaging only slightly attenuated this association (OR = 0.77, 95% CI: 0.75 to 0.80). The association with lower odds of advanced-stage diagnosis remained, regardless of whether COPD was previously diagnosed (OR = 0.68, 95% CI: 0.66 to 0.70) or undiagnosed (OR = 0.77, 95% CI: 0.73 to 0.82). Although most lung cancers are detected in the advanced stages, underlying COPD was associated with early-stage detection. Lung cancer diagnostics may benefit from enhanced partnership with COPD healthcare providers.

Members of the SLC26 family constitute a conserved class of anion transport proteins, which encompasses uncoupled transporters with channel-like properties, coupled exchangers and motor proteins. Among the 10 functional paralogs in humans, several participate in the secretion of bicarbonate in exchange with chloride and thus play an important role in maintaining pH homeostasis. Previously, we have elucidated the structure of murine SLC26A9 and defined its function as an uncoupled chloride transporter (Walter et al., 2019). Here we have determined the structure of the closely related human transporter SLC26A6 and characterized it as a coupled exchanger of chloride with bicarbonate and presumably also oxalate. The structure defines an inward-facing conformation of the protein that generally resembles known structures of SLC26A9. The altered anion selectivity between both paralogs is a consequence of a remodeled ion binding site located in the center of a mobile unit of the membrane-inserted domain, which also accounts for differences in the coupling mechanism., Competing Interests: DT, CB, SB, MS, RD No competing interests declared, (© 2023, Tippett et al.)

Inositol pyrophosphates are important biomolecules associated with apoptosis, cell growth and kinase regulation, yet their exact biological roles are still emerging and probes do not exist for their selective detection. We report the first molecular probe for the selective and sensitive detection of the most abundant cellular inositol pyrophosphate 5-PP-InsP 5 , as well as an efficient new synthesis. The probe is based on a macrocyclic Eu(iii) complex bearing two quinoline arms providing a free coordination site at the Eu(iii) metal centre. Bidentate binding of the pyrophosphate group of 5-PP-InsP 5 to the Eu(iii) ion is proposed, supported by DFT calculations, giving rise to a selective enhancement in Eu(iii) emission intensity and lifetime. We demonstrate the use of time-resolved luminescence as a bioassay tool for monitoring enzymatic processes in which 5-PP-InsP 5 is consumed. Our probe offers a potential screening methodology to identify drug-like compounds that modulate the activity of enzymes of inositol pyrophosphate metabolism., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Here we present a new method to monitor fluoride transmembrane transport into liposomes using a europium(III) complex. We take advantage of the long emission lifetime of this probe to measure the transport activity of a fluorescent transporter. The high sensitivity, selectivity, and versatility of the assay allowed us to study different types of fluoride transporters and unravel their mechanisms of action.

Synthetic ionophores able to transport bicarbonate and chloride anions across lipid bilayers are appealing for their wide range of potential biological applications. We have studied the bicarbonate and chloride transport by carbazoles with two amido/thioamido groups using a bicarbonate-sensitive europium(III) probe in liposomes and found a highly remarkable transporter concentration dependence. This can be explained by a combination of two distinct transport mechanisms: HCO 3 - /Cl - exchange and a combination of unassisted CO 2 diffusion and HCl transport, of which the respective contributions were quantified. The compounds studied were found to be highly potent HCl transporters. Based on the mechanistic insights on anion transport, we have tested the antimicrobial activity of these compounds and found a good correlation with their ion transport properties and a high activity against Gram-positive bacteria.

Bambusurils are macrocyclic molecules that are known for their high binding affinity and selectivity toward anions. Here, we present the preparation of two bambusurils bearing fluorinated substituents and one carboxylic function. These monofunctionalized bambusurils were conjugated with crown ether and cholesterol units. The resulting conjugates were successfully tested in liquid-liquid extraction of inorganic salts and chloride/bicarbonate transport across lipid bilayers.

Restoring sensation after injury or disease requires a reproducible method for generating large quantities of bona fide somatosensory interneurons. Toward this goal, we assess the mechanisms by which dorsal spinal interneurons (dIs; dI1-dI6) can be derived from mouse embryonic stem cells (mESCs). Using two developmentally relevant growth factors, retinoic acid (RA) and bone morphogenetic protein (BMP) 4, we recapitulate the complete in vivo program of dI differentiation through a neuromesodermal intermediate. Transcriptional profiling reveals that mESC-derived dIs strikingly resemble endogenous dIs, with the correct molecular and functional signatures. We further demonstrate that RA specifies dI4-dI6 fates through a default multipotential state, while the addition of BMP4 induces dI1-dI3 fates and activates Wnt signaling to enhance progenitor proliferation. Constitutively activating Wnt signaling permits the dramatic expansion of neural progenitor cultures. These cultures retain the capacity to differentiate into diverse populations of dIs, thereby providing a method of increasing neuronal yield., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Changes in phenology and distribution are being widely reported for many migratory species in response to shifting environmental conditions. Understanding these changes and the situations in which they occur can be aided by understanding consistent individual differences in phenology and distribution and the situations in which consistency varies in strength or detectability. Studies tracking the same individuals over consecutive years are increasingly reporting migratory timings to be a repeatable trait, suggesting that flexible individual responses to environmental conditions may contribute little to population-level changes in phenology and distribution. However, how this varies across species and sexes, across the annual cycle and in relation to study (tracking method, study design) and/or ecosystem characteristics is not yet clear. Here, we take advantage of the growing number of publications in movement ecology to perform a phylogenetic multilevel meta-analysis of repeatability estimates for avian migratory timings to investigate these questions. Of 2,433 reviewed studies, 54 contained suitable information for meta-analysis, resulting in 177 effect sizes from 47 species. Individual repeatability of avian migratory timings averaged 0.414 (95% confidence interval: 0.3-0.5) across landbirds, waterbirds and seabirds, suggesting consistent individual differences in migratory timings is a common feature of migratory systems. Timing of departure from the non-breeding grounds was more repeatable than timings of arrival at or departure from breeding grounds, suggesting that conditions encountered on migratory journeys and outcome of breeding attempts can influence individual variation. Population-level shifts in phenology could arise through individual timings changing with environmental conditions and/or through shifts in the numbers of individuals with different timings. Our findings suggest that, in addition to identifying the conditions associated with individual variation in phenology, exploring the causes of between-individual variation will be key in predicting future rates and directions of changes in migratory timings. We therefore encourage researchers to report the within- and between- individual variance components underpinning the reported repeatability estimates to aid interpretation of migration behaviour. In addition, the lack of studies in the tropics means that levels of repeatability in less strongly seasonal environments are not yet clear., (© 2022 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.)

Ligating a protein at a specific site with a tag molecule containing a paramagnetic metal ion provides a versatile way of generating pseudocontact shifts (PCSs) in nuclear magnetic resonance (NMR) spectra. PCSs can be observed for nuclear spins far from the tagging site, and PCSs generated from multiple tagging sites have been shown to enable highly accurate structure determinations at specific sites of interest, even when using flexible tags, provided the fitted effective magnetic susceptibility anisotropy ( Δ χ ) tensors accurately back-calculate the experimental PCSs measured in the immediate vicinity of the site of interest. The present work investigates the situation where only the local structure of a protein region or bound ligand is to be determined rather than the structure of the entire molecular system. In this case, the need for gathering structural information from tags deployed at multiple sites may be queried. Our study presents a computational simulation of the structural information available from samples produced with single tags attached at up to six different sites, up to six different tags attached to a single site, and in-between scenarios. The results indicate that the number of tags is more important than the number of tagging sites. This has important practical implications, as it is much easier to identify a single site that is suitable for tagging than multiple ones. In an initial experimental demonstration with the ubiquitin mutant S57C, PCSs generated with four different tags at a single site are shown to accurately pinpoint the location of amide protons in different segments of the protein., Competing Interests: At least one of the (co-)authors is a member of the editorial board of Magnetic Resonance. The peer-review process was guided by an independent editor, and the authors also have no other competing interests to declare., (Copyright: © 2022 Henry W. Orton et al.)

The dynamics of wild populations are governed by demographic rates which vary spatially and/or temporally in response to environmental conditions. Conservation actions for widespread but declining populations could potentially exploit this variation to target locations (or years) in which rates are low, but only if consistent spatial or temporal variation in demographic rates occurs. Using long-term demographic data for wild birds across Europe, we show that productivity tends to vary between sites (consistently across years), while survival rates tend to vary between years (consistently across sites), and that spatial synchrony is more common in survival than productivity. Identifying the conditions associated with low demographic rates could therefore facilitate spatially targeted actions to improve productivity or (less feasibly) forecasting and temporally targeting actions to boost survival. Decomposing spatio-temporal variation in demography can thus be a powerful tool for informing conservation policy and for revealing appropriate scales for actions to influence demographic rates., Competing Interests: We declare we have no competing interests., (© 2022 The Authors.)

Background: In migratory species, the extent of within- and between-individual variation in migratory strategies can influence potential rates and directions of responses to environmental changes. Quantifying this variation requires tracking of many individuals on repeated migratory journeys. At temperate and higher latitudes, low levels of within-individual variation in migratory behaviours are common and may reflect repeated use of predictable resources in these seasonally-structured environments. However, variation in migratory behaviours in the tropics, where seasonal predictability of food resources can be weaker, remains largely unknown., Methods: Round Island petrels (Pterodroma sp.) are tropical, pelagic seabirds that breed all year round and perform long-distance migrations. Using multi-year geolocator tracking data from 62 individuals between 2009 and 2018, we quantify levels of within- and between-individual variation in non-breeding distributions and timings., Results: We found striking levels of between-individual variation in at-sea movements and timings, with non-breeding migrations to different areas occurring across much of the Indian Ocean and throughout the whole year. Despite this, repeat-tracking of individual petrels revealed remarkably high levels of spatial and temporal consistency in within-individual migratory behaviour, particularly for petrels that departed at similar times in different years and for those departing in the austral summer. However, while the same areas were used by individuals in different years, they were not necessarily used at the same times during the non-breeding period., Conclusions: Even in tropical systems with huge ranges of migratory routes and timings, our results suggest benefits of consistency in individual migratory behaviours. Identifying the factors that drive and maintain between-individual variation in migratory behaviour, and the consequences for breeding success and survival, will be key to understanding the consequences of environmental change across migratory ranges., (© 2022. The Author(s).)

The design of molecular receptors that bind and sense anions in biologically relevant aqueous solutions is a key challenge in supramolecular chemistry. The recognition of inorganic phosphate is particularly challenging because of its high hydration energy and pH dependent speciation. Adenosine monophosphate (AMP) represents a valuable but elusive target for supramolecular detection because of its structural similarity to the more negatively charged anions, ATP and ADP. We report two new macrocyclic Eu(iii) receptors capable of selectively sensing inorganic phosphate and AMP in water. The receptors contain a sterically demanding 8-(benzyloxy)quinoline pendant arm that coordinates to the metal centre, creating a binding pocket suitable for phosphate and AMP, whilst excluding potentially interfering chelating anions, in particular ATP, bicarbonate and lactate. The sensing selectivity of our Eu(iii) receptors follows the order AMP > ADP > ATP, which represents a reversal of the order of selectivity observed for most reported nucleoside phosphate receptors. We have exploited the unique host-guest induced changes in emission intensity and lifetime for the detection of inorganic phosphate in human serum samples, and for monitoring the enzymatic production of AMP in real-time., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Sulfotransferases constitute a ubiquitous class of enzymes which are poorly understood due to the lack of a convenient tool for screening their activity. These enzymes use the anion PAPS (adenosine-3'-phosphate-5'-phosphosulfate) as a donor for a broad range of acceptor substrates, including carbohydrates, producing sulfated compounds and PAP (adenosine-3',5'-diphosphate) as a side product. We present a europium(III)-based probe that binds reversibly to both PAPS and PAP, producing a larger luminescence enhancement with the latter anion. We exploit this greater emission enhancement with PAP to demonstrate the first direct real-time assay of a heparan sulfate sulfotransferase using a multi-well plate format. The selective response of our probe towards PAP over structurally similar nucleoside phosphate anions, and over other anions, is investigated and discussed. This work opens the possibility of investigating more fully the roles played by this enzyme class in health and disease, including operationally simple inhibitor screening.

The metallo- β -lactamase IMP-1 features a flexible loop near the active site that assumes different conformations in single crystal structures, which may assist in substrate binding and enzymatic activity. To probe the position of this loop, we labelled the tryptophan residues of IMP-1 with 7- 13 C-indole and the protein with lanthanoid tags at three different sites. The magnetic susceptibility anisotropy ( Δ χ ) tensors were determined by measuring pseudocontact shifts (PCSs) of backbone amide protons. The Δ χ tensors were subsequently used to identify the atomic coordinates of the tryptophan side chains in the protein. The PCSs were sufficient to determine the location of Trp28, which is in the active site loop targeted by our experiments, with high accuracy. Its average atomic coordinates showed barely significant changes in response to the inhibitor captopril. It was found that localisation spaces could be defined with better accuracy by including only the PCSs of a single paramagnetic lanthanoid ion for each tag and tagging site. The effect was attributed to the shallow angle with which PCS isosurfaces tend to intersect if generated by tags and tagging sites that are identical except for the paramagnetic lanthanoid ion., Competing Interests: At least one of the (co-)authors is a member of the editorial board of Magnetic Resonance. The peer-review process was guided by an independent editor, and the authors also have no other competing interests to declare., (Copyright: © 2022 Henry W. Orton et al.)

Natural sounds, and bird song in particular, play a key role in building and maintaining our connection with nature, but widespread declines in bird populations mean that the acoustic properties of natural soundscapes may be changing. Using data-driven reconstructions of soundscapes in lieu of historical recordings, here we quantify changes in soundscape characteristics at more than 200,000 sites across North America and Europe. We integrate citizen science bird monitoring data with recordings of individual species to reveal a pervasive loss of acoustic diversity and intensity of soundscapes across both continents over the past 25 years, driven by changes in species richness and abundance. These results suggest that one of the fundamental pathways through which humans engage with nature is in chronic decline, with potentially widespread implications for human health and well-being., (© 2021. The Author(s).)

Purpose: This study reports on the prevalence and impact of pain in individuals with different chronic respiratory diseases attending pulmonary rehabilitation (PR). Method: A retrospective review of medical records data was conducted for 488 participants who had attended a PR programme over a 2-year period. Data on pain and medication history taken from multidisciplinary medical records, together with participant demographics and PR outcomes, were extracted. We compared pain among participants with different types of chronic respiratory disease. Results: The overall prevalence of pain was 77%, with a significantly higher prevalence among individuals with obstructive lung diseases (80%) compared with restrictive lung diseases (69%; p  = 0.04). Some participants (17%) who took pain medications did not discuss pain with their clinicians. The presence of pain and different reporting of pain did not have a negative impact on the PR programme completion rate ( p  = 0.74), improvements in exercise capacity ( p  = 0.51), or health-related quality of life (all four chronic respiratory disease questionnaire domains, p >0.05). Conclusions: The prevalence of pain is high among individuals with chronic respiratory disease attending PR. The presence or absence of pain was not negatively associated with the programme completion rate or PR outcomes; therefore, pain should not deter clinicians from referring patients to PR., (© Canadian Physiotherapy Association.)

A lanthanide-binding tag site-specifically attached to a protein presents a tool to probe the protein by multiple spectroscopic techniques, including nuclear magnetic resonance, electron paramagnetic resonance and time-resolved luminescence spectroscopy. Here a new stable chiral Ln III tag, referred to as C12, is presented for spontaneous and quantitative reaction with a cysteine residue to generate a stable thioether bond. The synthetic protocol of the tag is relatively straightforward, and the tag is stable for storage and shipping. It displays greatly enhanced reactivity towards selenocysteine, opening a route towards selective tagging of selenocysteine in proteins containing cysteine residues. Loaded with Tb III or Tm III ions, the C12 tag readily generates pseudocontact shifts (PCS) in protein NMR spectra. It produces a relatively rigid tether between lanthanide and protein, which is beneficial for interpretation of the PCSs by single magnetic susceptibility anisotropy tensors, and it is suitable for measuring distance distributions in double electron-electron resonance experiments. Upon reaction with cysteine or other thiol compounds, the Tb III complex exhibits a 100-fold enhancement in luminescence quantum yield, affording a highly sensitive turn-on luminescence probe for time-resolved FRET assays and enzyme reaction monitoring., (© 2021 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

The spinal cord is functionally and anatomically divided into ventrally derived motor circuits and dorsally derived somatosensory circuits. Sensory stimuli originating either at the periphery of the body, or internally, are relayed to the dorsal spinal cord where they are processed by distinct classes of sensory dorsal interneurons (dIs). dIs convey sensory information, such as pain, heat or itch, either to the brain, and/or to the motor circuits to initiate the appropriate response. They also regulate the intensity of sensory information and are the major target for the opioid analgesics. While the developmental mechanisms directing ventral and dorsal cell fates have been hypothesized to be similar, more recent research has suggested that dI fates are specified by novel mechanisms. In this review, we will discuss the molecular events that specify dorsal neuronal patterning in the spinal cord, thereby generating diverse dI identities. We will then discuss how this molecular understanding has led to the development of robust stem cell methods to derive multiple spinal cell types, including the dIs, and the implication of these studies for treating spinal cord injuries and neurodegenerative diseases. This article is categorized under: Neurological Diseases > Stem Cells and Development., (© 2021 The Authors. WIREs Mechanisms of Disease published by Wiley Periodicals LLC.)

We present here a series of thermoresponsive glycopolymers in the form of poly( N -isopropylacrylamide) -co- (2-[β-manno[oligo]syloxy] ethyl methacrylate)s. These copolymers were prepared from oligo-β-mannosyl ethyl methacrylates that were synthesized through enzymatic catalysis, and were subsequently investigated with respect to their aggregation and phase behavior in aqueous solution using a combination of 1 H NMR spectroscopy, dynamic light scattering, cryogenic transmission electron microscopy (TEM), and small-angle X-ray scattering (SAXS). The thermoresponsive glycopolymers were prepared by conventional free radical copolymerization of different mixtures of 2-(β-manno[oligo]syloxy)ethyl methacrylates (with either one or two saccharide units) and N -isopropylacrylamide (NIPAm). The results showed that below the lower critical solution temperature (LCST) of poly(NIPAm), the glycopolymers readily aggregate into nanoscale structures, partly due to the presence of the saccharide moieties. Above the LCST of poly(NIPAm), the glycopolymers rearrange into a heterogeneous mixture of fractal and disc/globular aggregates. Cryo-TEM and SAXS data demonstrated that the presence of the pendant β-mannosyl moieties in the glycopolymers induces a gradual conformational change over a wide temperature range. Even though the onset of this transition is not different from the LCST of poly(NIPAm), the gradual conformational change offers a variation of the temperature-dependent properties in comparison to poly(NIPAm), which displays a sharp coil-to-globule transition. Importantly, the compacted form of the glycopolymers shows a larger colloidal stability compared to the unmodified poly(NIPAm). In addition, the thermoresponsiveness can be conveniently tuned by varying the sugar unit-length and the oligo-β-mannosyl ethyl methacrylate content.

Wildlife conservation policies directed at common and widespread, but declining, species are difficult to design and implement effectively, as multiple environmental changes are likely to contribute to population declines. Conservation actions ultimately aim to influence demographic rates, but targeting actions towards feasible improvements in these is challenging in widespread species with ranges that encompass a wide range of environmental conditions. Across Europe, sharp declines in the abundance of migratory landbirds have driven international calls for action, but actions that could feasibly contribute to population recovery have yet to be identified. Targeted actions to improve conditions on poor-quality sites could be an effective approach, but only if local conditions consistently influence local demography and hence population trends. Using long-term measures of abundance and demography of breeding birds at survey sites across Europe, we show that co-occurring species with differing migration behaviours have similar directions of local population trends and magnitudes of productivity, but not survival rates. Targeted actions to boost local productivity within Europe, alongside large-scale (non-targeted) environmental protection across non-breeding ranges, could therefore help address the urgent need to halt migrant landbird declines. Such demographic routes to recovery are likely to be increasingly needed to address global wildlife declines.

We describe two differentiation protocols to derive sensory spinal interneurons (INs) from human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs). In protocol 1, we use retinoic acid (RA) to induce pain, itch, and heat mediating dI4/dI6 interneurons, and in protocol 2, RA with bone morphogenetic protein 4 (RA+BMP4) is used to induce proprioceptive dI1s and mechanosensory dI3s in hPSC cultures. These protocols provide an important step toward developing therapies for regaining sensation in spinal cord injury patients. For complete details on the use and execution of this protocol, please refer to Gupta et al. (2018)., Competing Interests: The authors declare no competing interests., (© 2021 The Authors.)

A new synthetic strategy for the preparation of macromolecular MRI contrast agents (CAs) is reported. Four gadolinium(iii) complexes bearing either one or two polymerizable methacrylamide groups were synthesized, serving as monomers or crosslinkers for the preparation of water-soluble, polymeric CAs using Reversible Addition-Fragmentation Chain Transfer (RAFT) polymerization. Using this approach, macromolecular CAs were synthesized with different architectures, including linear, hyperbranched polymers and gels. The relaxivities of the polymeric CAs were determined by NMR relaxometry, revealing an up to 5-fold increase in relaxivity (60 MHz, 310 K) for the linear polymers compared with the clinically used CA, Gd-DOTA. Moreover, hyperbranched polymers obtained from Gd(iii) crosslinkers, displayed even higher relaxivities up to 22.8 mM -1 s -1 , approximately 8 times higher than that of Gd-DOTA (60 MHz, 310 K). A detailed NMRD study revealed that the enhanced relaxivities of the hyperbranched polymers were obtained by limiting the local motion of the crosslinked Gd(iii) chelate. The versatility of RAFT polymerization of Gd(iii) monomers and crosslinkers opens the doors to more advanced polymeric CAs capable of multimodal, bioresponsive or targeting properties., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Luminescent lanthanide complexes have been actively studied as selective anion receptors for the past two decades. Ln(iii) complexes, particularly of europium(iii) and terbium(iii), offer unique photophysical properties that are very valuable for anion sensing in biological media, including long luminescence lifetimes (milliseconds) that enable time-gating methods to eliminate background autofluorescence from biomolecules, and line-like emission spectra that allow ratiometric measurements. By careful design of the organic ligand, stable Ln(iii) complexes can be devised for rapid and reversible anion binding, providing a luminescence response that is fast and sensitive, offering the high spatial resolution required for biological imaging applications. This review focuses on recent progress in the development of Ln(iii) receptors that exhibit sufficiently high anion selectivity to be utilised in biological or environmental sensing applications. We evaluate the mechanisms of anion binding and sensing, and the strategies employed to tune anion affinity and selectivity, through variations in the structure and geometry of the ligand. We highlight examples of luminescent Ln(iii) receptors that have been utilised to detect and quantify specific anions in biological media ( e.g. human serum), monitor enzyme reactions in real-time, and visualise target anions with high sensitivity in living cells., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The design and synthesis of molecular receptors for the selective binding of nucleoside phosphate anions (e. g. ATP, ADP, GTP, GDP, UDP) in aqueous media at physiological pH is a valuable research endeavour, which could lead to new sensing tools for biomedical and drug discovery research. However, this target is very challenging due to similarities in anion size, structure and charge. This Minireview provides an account of the development of receptors capable of discriminating between ATP and ADP, and their utilisation in biological sensing applications. Particular focus is given to the application of receptors for the determination of ATP or ADP concentrations in biological media, tracking ATP levels (or the ATP/ADP ratio) in cells using fluorescence microscopy, or real-time monitoring of enzyme reactions involving ATP and ADP in vitro., (© 2020 The Authors. ChemPlusChem published by Wiley-VCH GmbH.)

Commissural axons have been a key model system for identifying axon guidance signals in vertebrates. This review summarizes the current thinking about the molecular and cellular mechanisms that establish a specific commissural neural circuit: the dI1 neurons in the developing spinal cord. We assess the contribution of long- and short-range signaling while sequentially following the developmental timeline from the birth of dI1 neurons, to the extension of commissural axons first circumferentially and then contralaterally into the ventral funiculus., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Non-thermal plasma (NTP), an ionized gas generated at ambient pressure and temperature, has been an emerging technology for medical applications. Through controlled delivery of reactive oxygen and nitrogen species (ROS/RNS), NTP can elicit hormetic cellular responses, thus stimulating broad therapeutic effects. To enable clinical translation of the promising preclinical research into NTP therapy, a deeper understanding of NTP interactions with clinical substrates is profoundly needed. Since NTP-generated ROS/RNS will inevitably interact with blood in several clinical contexts, understanding their stability in this system is crucial. In this study, two medically relevant NTP delivery modalities were used to assess the stability of NTP-generated ROS/RNS in three aqueous solutions with increasing organic complexities: phosphate-buffered saline (PBS), blood plasma (BP), and processed whole blood. NTP-generated RNS collectively (NO 2 - , ONOO - ), H 2 O 2 , and ONOO - exclusively were analyzed over time. We demonstrated that NTP-generated RNS and H 2 O 2 were stable in PBS but scavenged by different components of the blood. While RNS remained stable in BP after initial scavenging effects, it was completely reduced in processed whole blood. On the other hand, H 2 O 2 was completely scavenged in both liquids over time. Our previously developed luminescent probe europium(III) was used for precision measurement of ONOO - concentration. NTP-generated ONOO - was detected in all three liquids for up to at least 30 seconds, thus highlighting its therapeutic potential. Based on our results, we discussed the necessary considerations to choose the most optimal NTP modality for delivery of ROS/RNS to and via blood in the clinical context., Competing Interests: The authors declare no conflict of interest., (Copyright © 2020 Abraham Lin et al.)